ABSTRACTS OF K99/R00 PATHWAY TO INDEPENDENCE AWARDS

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99AA016731-01       

 

Program Director:

GRANDISON, LINDSEY

Principal Investigator:

SABINO, VALENTINA                     

PHD

Title:

Role of sigma receptors in ethanol reinforcement

Institution:

SCRIPPS RESEARCH INSTITUTE

LA JOLLA, CA

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant): Summary: The application proposes a career development plan for Dr. Valentina Sabino, a pharmacologically-trained post-doctoral fellow committed to a research career in ethanol addiction aimed towards understand its molecular basis. The applicant will be mentored by Dr. George Koob in behavioral neuroscience methods and animal models of alcoholism and co-mentored by Dr. Pietro Sanna in immunohistochemical and molecular techniques. The project, to be conducted at The Scripps Research Institute in the rich neuroscience community of San Diego, concerns sigma receptors, unique mammalian binding sites that modulate other neurotransmitter systems and which are richly expressed in limbic brain structures. Pharmacological studies indicate that sigma receptors modulate actions of cocaine and methamphetamine. Recently, sigma receptors also have been proposed to modulate motivating properties of ethanol, consistent with findings of sigma receptor polymorphisms in human alcoholism.   Until very recently, however, the understanding of sigma receptor systems had been hampered by the unavailability of specific, subtype-selective ligands or of mutant mouse models that lack sigma receptor subtypes. Furthermore, the role of sigma receptors in voluntary intake or self-administration of ethanol are unknown. The present multipdisciplinary application uses behavioral, pharmacologic, and molecular techniques to determine the modulatory role of sigma receptors with subtype specificity on ethanol reward and reinforcement in distinct models of excessive ethanol consumption. Two models of excess ethanol intake will be studied in Specific Aims 1 and 3 -- genetically selected alcohol-preferring rats and withdrawn outbred rats made dependent during chronic, intermittent exposure to ethanol vapor, emphasizing positive and negative reinforcing properties of ethanol, respectively. Ethanol self-administration will be pharmacologically modulated (in Specific Aim 1), through the administration of novel a receptor ligands, and molecularly (in Specific Aim 2), through the use of o-1 receptor KO mice. The impact of chronic exposure to ethanol and of innate preference for ethanol on o receptor protein expression in discrete limbic brain regions will be investigated in Specific Aim 3. Relevance: The project will define the physiologic and potential therapeutic relevance of an under characterized modulatory receptor system for alcohol abuse and dependence.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99AG029726-01       

 

Program Director:

BUCKHOLTZ, NEIL

Principal Investigator:

TOWN, TERRENCE C                    

PHD

Title:

Blocking TGF-Beta immune signaling as a therapeutic target for Alzheimer's diseas

Institution:

YALE UNIVERSITY

NEW HAVEN, CT

Project Period:

2006/12/01-2007/11/30

 

 

 

  DESCRIPTION (provided by applicant): The overriding aim of this proposal is to investigate the therapeutic potential of blocking transforming growth factor-beta (TGF-beta) signaling for Alzheimer's disease. Terrence Town, Ph.D. is currently an NRSA/NIA post-doctoral fellow with the immediate goal of completing an additional year of mentored research. Dr. Town has been working at the interface of the immunology and neuroscience fields, and his current environment in Dr. Flavell's laboratory with co-sponsorship from Dr. Rakic positions him in the ideal environment within which to complete the mentored phase of the proposed project. Dr. Town's long-term goals inclulde establishing himself as an independent scientist in a tenure-track academic position, and contributing to understanding neuroimmune aspects of Alzheimer's disease, with the hope of finding novel therapeutic targets for this devastating illness. Dr. Town's career development plan includes receiving training and mentorship in neuroimmunology. Following the proposed one year period of mentored research, Dr. Town plans to make the transition to independence with the assistance of the proposed award. For the mentored period, Dr. Town proposes to evaluate Alzheimer-like pathology in a transgenic mouse model of the disease crossed with a transgenic mouse that has blocked TGF-beta signaling in innate immune cells. The proposed work during the mentored phase builds heavily on preliminary data that show that one such crossed mouse has mitigation of Alzheimer-like pathology. For the independent phase, Dr. Town will 1) investigate the potential cellular mechanism underlying reduced Alzheimer pathology in crossed mice, 2) adopt a pharmacotherapeutic approach by treating Alzheimer transgenic mice with TGF-beta receptor blocking antibody, and 3) conduct another mouse crossing experiment to determine if blocking TGF-beta signaling on innate immune cells mitigates Alzheimer-like pathology during its initial establishment or after active lesions are formed. RELEVANCE: Alzheimer's disease is the most common dementing illness in the United States, and it is estimated that over 3 million Americans over the age of 65 have the disease. This project aims to uncover a new avenue for the treatment of Alzheimer's disease by blocking a protein that has been shown to be involved in the pathological changes of the disease, specifically the brain's inflammatory response.    

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99AG029760-01       

 

Program Director:

KOHANSKI, RONALD

Principal Investigator:

ROSSI, DERRICK J.                     

PHD

Title:

Stem Cell Aging: Functional Decline, DNA damage and Therapeutic Targets

Institution:

STANFORD UNIVERSITY

STANFORD, CA

Project Period:

2006/12/01-2008/11/01

 

 

 

  DESCRIPTION (provided by applicant): The etiology of the age-associated pathophysiological changes of the hematopoietic system including the onset of anemia, diminished immune competence, and myelogenous disease development suggests profound losses of homeostatic control. Because homeostatic control is mediated by the activity of stem and progenitor cells, we propose that the homeostatic imbalances associated with the aged hematopoietic system result from alterations in the prevalence and/or functional capacity of hematopoietic stem and progenitor cells. The mechanisms driving loss of homeostatic control are poorly understood. The accumulation of somatic damage to cellular macromolecules is considered to be a major cause of cellular attrition and aging. In particular, the accumulation of DMA damage has been implicated as a central mechanism contributing to age-associated decline. In such a model of aging, DMA damage accrues in cells as they age and when accumulated damage becomes sufficiently disruptive can drive cells to 1) malignant transformation 2) cellular senescence, 3) programmed cell death, or 4) dysfunction. When this aging paradigm is considered within the context of stem cell biology, malignant transformation of stem cells would be predicted to result in increased cancer stem cell development, while stem cell senescence, cell death, and dysfunction would be predicted to lead to the diminished functional stem cell reserves. If stem cell depletion surpasses levels of stem cell self-renewal, then homeostatic failure - the physiological hallmark of aging - ensues.   The objective of our research is to functionally characterize hematopoietic stem and progenitor cell aging to determine the extent to which dysfunction of these cells contributes to age- associated pathophysiological decline, and to uncover the extent to which this dysfunction is driven by accumulated DMA damage.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99AI072834-01       

 

Program Director:

PETERS, N. KENT

Principal Investigator:

GALONIC, DANICA P                    

PHD

Title:

Methylation in Antibiotic Biosynthesis: Methylcobalamin-Radical SAM Enzymes

Institution:

HARVARD UNIVERSITY (MEDICAL SCHOOL)

BOSTON, MA

Project Period:

2006/12/01-2007/11/30

 

 

 

  DESCRIPTION (provided by applicant): I have obtained B.Sc. in chemistry from University of Belgrade, Serbia and Montenegro , in 2000, and Ph.D. in organic chemistry from University of Illinois at Urbana-Champaign in May 2005. During graduate studies, I have developed new methods for the chemoselective carbohydrate-peptide ligations under the joint guidance of Professors David Y. Gin and Wilfred A. van der Donk. Currently, I am a Damon Runyon Cancer Research Foundation postdoctoral fellow in the laboratory of Professor Christopher T. Walsh at Harvard Medical School. HMS and Professor Walsh is providing an outstanding research environment and is committed to the success of the postdoctoral fellows. My postdoctoral research is focused on the characterization of a recently discovered class of nonheme Fe (II) halogenases, capable of carrying out halogenation of unactivated carbon centers. Thus far, we have reconstituted halogenation activity in the barbamide system. In this study, we demonstrated that the triple chlorination of the unactivated methyl group of the carrier-protein tethered L-leucine substrate is mediated by the tandem action of two nonheme Fell halogenases, BarB1 and BarB2. I am currently investigating mechanistic aspects of halogenation of unactivated carbon centers through the investigation of pre-steady state kinetic parameters and EPR and Mossbauer investigation of metal center during the catalysis. The objective of the proposed project is mechanistic description of methylcobalamin-radical SAM enzymes that carry out methylations of sp2 carbon centers in antibiotic biosynthesis. Our goal is to understand the logic that nature uses to channel methylcobalamin, iron-sulfur clusters and deoxyadenosyl radicals to perform this novel carbon-carbon bond formation in enzymology. The methylation event will be studied in the context of generation of the 5-methylpyrrole-2-carboxylate pharmacophore in aminocoumarin antibiotic biosynthesis, and hydroxyethyl side chain in the biosynthesis of beta lactam antibiotic thienamycin. Better understanding of enzymes involved in the antibiotic biosynthesis can lead to the development of new antibiotic variants through combinatorial biosynthesis. This is especially important because of the development of bacterial resistance to commonly used antibiotics.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99AI072955-01       

 

Program Director:

PROGRAIS, LAWRENCE J.

Principal Investigator:

KAGAN, JONATHAN C                    

PHD

Title:

Cellular and molecular aspects of Toll-like receptor signal transduction.

Institution:

YALE UNIVERSITY

NEW HAVEN, CT

Project Period:

2006/12/01-2007/11/30

 

 

 

  DESCRIPTION (provided by applicant): The ability to mount an effective immune response is critical for human health. Toll-like receptors (TLRs) are transmembrane proteins expressed on phagocytes and other cells that act as sensors of microbial infection. Recent studies have underscored the importance of TLRs in innate and adaptive immunity as mice deficient in TLR signaling have defects in controlling bacterial and viral infections. Despite the identification of several genes required for TLR signaling, a clear picture of how TLR signaling complexes are assembled and how assembly is regulated is lacking. This proposal will investigate cellular and molecular aspects of TLR signal transduction. We will focus on the characterization of the four essential TLR adaptor proteins in terms of their localization and recruitment to membranes bearing activated TLRs. Cis-acting domains that mediate adaptor localization and recruitment to TLRs will be identified and mutated as a means of addressing the functional significance of adaptor localization in TLR signaling. Trans-acting factors that regulate adaptor localization will be identified with a particular focus on the transport regulation by phosphoinositides. The successful completion of this project will yield important insight into cellular control of TLR signal transduction and thus, mechanisms of immunity.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99AI072973-01       

 

Program Director:

WASSEF, NABILA M.

Principal Investigator:

ALTER, GALIT                     

PHD

Title:

Anergizing effect of NK cell receptor expression on HIV-specific CD8+ T cells

Institution:

MASSACHUSETTS GENERAL HOSPITAL

BOSTON, MA

Project Period:

2006/12/01-2007/11/30

 

 

 

  DESCRIPTION (provided by applicant): Virus-specific-CD8+ T cells play a central role in the control of viral infections by direct elimination of infected cells and secretion of a number of soluble factors. However, despite the induction of strong and broad HIV specific CD8+ T cell responses in chronic HIV-1 infection, these cells progressively lose critical effector functions. A number of recent studies have shown that a significant subset of CD8+ T cells appear to upregulate inhibitory "NK cell receptor" expression following encounter with antigen, and that CD8+ T cells expressing NK cell receptors persist in chronically infected mice but not in mice that clear the infection. These receptors included members of the KIR family, as well as of the C-type lectin family (NKG2) in humans and the Ly49 family in mice. The expression of these receptors on CD8+ T cells can have a profound effect on the functional capacity of both tumor-specific and virus-specific T cells. Recently, increased levels of KIR and NKG2A expression have also been described on discrete populations of CD8+ T cells in chronic HIV-1 infection. Given the profound inhibitory effect of these receptors, this application aims to gain a better understanding of the role of KIR and NKG2A receptor expression on HIV-1-specific CD8+ T cell function. In this application, the expression profile of both KIR and NKG2 receptors will be characterized on CD8+ T cells in subjects at different stages of HIV-1 infection to determine the kinetics of NK cell receptor upregulation in HIV-1 infection, to elucidate the impact of NK cell receptor expression on CD8+ T cell function, whether these receptors are preferentially enriched on the surface of HIV-specific CD8+ T cells, and whether this inhibitory effect can be reversed. Furthermore, the precise mechanisms accounting for NK cell receptor-mediated inhibition of CD8+ T cell activation will be characterized on the immunological synaptic level as well as the TCR signaling-cascade level. Thus this application aims to determine whether one of the mechanisms contributing to impaired CD8+ T cell activity during persistent viral infections may be due to an up-regulation of inhibitory NK cell receptors. These in depth studies geared towards understanding the underlying mechanism of KIR/NKG2A inhibitory activity on CD8+ T cells will certainly contribute to the field of basic CD8+ T cell biology and potentially allow for the identification of novel targets to reconstitute effective of CD8+ T cell immunity in the setting of chronic infections, such as HIV.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99CA125937-01       

 

Program Director:

ECKSTEIN, DAVID J

Principal Investigator:

XIN, LI                     

PHD

Title:

Characterization of prostatic stem cells and prostate cancer-initiating cells

Institution:

UNIVERSITY OF CALIFORNIA LOS ANGELES

LOS ANGELES, CA

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant): Prostate cancer is the second-leading cause of the cancer-related death in men in the United States. We have enriched prostate stem cell activity using the Sca-1 surface antigen and demonstrated that cells with enriched stem cell activity serve as a target for tumor initiation. Our long-term goals are to fully characterize the identity of stem cells and cancer-initiating cells in prostate. This study will provide general insights for the studies on stem cell biology and cancer biology.  Our specific aims are: (1) Fully characterize the prostatic stem cells. (A) We will investigate whether stem cells reside in a specific prostatic epithelial cell lineage using the dissociated prostate cell regeneration system. We will (i) isolate individual lineages and test their regenerative capacity, and (ii) permanently mark individual lineages and determine the lineage status of their progeny. These can be achieved by creating a prostate basal cell-specific green fluorescence protein-marked transgenic mouse model or through the Cre-loxp marking system regulated by prostate lineage-specific promoters. (B) We will continue to screen the expression of surface antigens in prostate, fractionate prostate cells using surface antigens and identify the fraction(s) with enriched stem cell activity using the regeneration system. (2) Identify the prostate cancer-initiating cells. (A) We will evaluate the susceptibility of basal cells and luminal cells to oncogenic transformation. We will induce Pten deletion in individual lineages by infecting prostate epithelial cells from the PTENIoxp/loxp transgenic mouse model with lentivirus that express the Cre recombinase regulated by lineage-specific promoters. Infected cells will be tested in the regeneration system to determine which cell lineage(s) have been transformed. (B) We will determine the susceptibility of each cell population fractionated in Aim1 B to malignant transformation induced by single or a combination of oncogenic stimuli. Cell fractions from the wild type and P53-/- mice that represent stem cells, short-term progenitor cells and terminally differentiated cells will be infected with lentivirus that mediate distinct oncogenic signals, such as myc, inactivation of the pRB family proteins, perturbations in the PTEN-AKT signaling pathway and others. The infected cells will be microinjected into immunodeficient host mouse prostate or tested in the regeneration system to determine their capacity to initiate cancer.     

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99CA125991-01       

 

Program Director:

ECKSTEIN, DAVID J

Principal Investigator:

LI, ZIQIANG                      

PHD

Title:

Dissect roles of mismatch repair proteins in Lymphomagenesis and Ig diversity

Institution:

YESHIVA UNIVERSITY

BRONX, NY

Project Period:

2007/03/01-2009/02/28

 

 

 

  DESCRIPTION (provided by applicant): Mismatch repair (MMR) proteins are responsible for removing DNA mismatches, inhibiting recombination between divergent DNA sequences, and signaling for apoptosis to maintain the integrity of the genome and to prevent malignant transformation. The generation of antibody diversity by B cells involves somatic hypermutation (SHM) and class switch recombination (CSR), two processes which are initiated by G-U mismatches generated by activation-induced cytidine deaminase (AID). Mistargeting of SHM and/or CSR leads to the B-cell malignancies. MMR proteins are involved in SHM and CSR presumably through the error-prone repair of G-U mismatches to increase the genomic instability of immunoglobulin (Ig) genes. However, how the error-prone MMR repair is achieved in activated B cells remains elusive. In addition, MMR proteins Msh2 and Msh6 form a heterodimer that recognizes mismatched bases and initiates the MMR process, but Msh2-/- mice die early predominantly from T-cell lymphomas and intestine tumors whereas Msh6-/- mice die later predominantly from B-cell lymphomas. To understand the difference between the function of Msh2 and that of Msh6 in mismatch repair, SHM and CSR, and B-cell lymphomagenesis, I propose to generate Msh2-/- Msh6-/- doubly deficient mice, to extensively characterize the lymphomas derived from various MMR deficient mice and mutant mice, and to determine the role of AID in B-cell malignancies by generating AID-/- MMR-/- mice.    

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99CA126173-01       

 

Program Director:

ECKSTEIN, DAVID J

Principal Investigator:

ZHANG, YOU-WEI                     

PHD

Title:

Roles of the Checkpoint Kinase Chk1 in Cancer Biology and Therapy

Institution:

SALK INSTITUTE FOR BIOLOGICAL STUDIES

LA JOLLA, CA

Project Period:

2006/12/01-2008/11/30

 

 

 

 DESCRIPTION (provided by applicant): Summary Eukaryotic cells have evolved an elaborate network of genome surveillance and repair proteins to insure that DNA replication will occur in an accurate and timely fashion. This surveillance pathway is termed the S phase replication checkpoint. Defects in this 'caretaker’machinery lead to genetic instability, a hallmark feature of human cancers. The replication checkpoint monitors the progress of replication forks, and when fork stalls, transmits signals that delay S-phase progression, and maintains the stability of stalled forks so that DNA replication can resume after the initial error is corrected. Two key components of the replication checkpoint are the apical protein kinase, ATR, and its downstream target kinase, Chk1. Loss of ATR or Chk1 function is lethal, even in the absence of extrinsic genotoxic stress, underscoring the importance of the replication checkpoint in the maintenance of cell viability. In preliminary work, we tested the hypothesis that certain anti-tumor agents, such as the topoisomerase 1 (Top I) poisons (e.g., camptothecin (CPT)) selectively kill cancer cells through the induction of protracted, high-intensity replication stress. Our studies unexpectedly revealed that treatment with CPT or other replication stress inducers (e.g., deep hypoxia or methylmethane sulfonate) triggers the ubiquitin-dependent degradation of Chk1 in both normal and transformed human cells. The degradation of Chk1 was dependent on the Skp1-Cullin-F-box (SCF) E3 ubiquitin ligase complex, and the consequences of severe Chk1 destruction were replication fork collapse and ultimate cell death. Remarkably, defects in the Chk1 degradation pathway confer resistance to the cytotoxic effect of CPT - a major problem with this class of drugs in the clinical arena. Thus, this novel layer of Chk1 regulation has important implications for our understanding of replication checkpoint signaling, as well as mechanisms of anticancer resistance in cancer patients. I now propose to elucidate the underlying mechanisms and biological significance of the stress-induced Chk1 destruction through pursuit of the following specific aims: In the mentored-phase, (1) To identify the F-box proteins of the E3 ligase complexes responsible for Chk1 destruction; In the independent phase, (2) To identify the putative 'Degron’region and the lysine residues targeted for ubiquitin modification in Chk1; (3) To investigate the roles of de-phosphorylation in Chk1 degradation; (4) To characterize the molecular mechanisms underlying the defect in Chk1 degradation in CPT-resistant cancer cells. Relevance: The results of these studies will not only advance our understanding of the genotoxic stress response machinery in human cells, but also provide novel insights into the causes of genetic instability and anticancer drug resistance in cancer cells, and these lines of research have direct implications for the development of novel therapeutic agents targeted against tumors.

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99CA126186-01       

 

Program Director:

ECKSTEIN, DAVID J

Principal Investigator:

HE, LIN                     

PHD

Title:

Functions of microRNAs in lymphomagenesis

Institution:

COLD SPRING HARBOR LABORATORY

COLD SPRING HARBOR, NY

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant): Malignant transformation represents the phenotypic endpoint of successive genetic lesions that confer uncontrolled proliferation and survival, unlimited replicative potential, and invasive growth. Recent evidence has suggested that non-coding RNAs, in particular, microRNAs (miRNAs), are subjected to changes in gene structure and expression regulation in tumors. I identified a polycistronic miRNA cluster, mir17-92, as a target of chromosome 13q31 amplicon found in human B-cell lymphomas. In a mouse model for B-cell lymphoma, enforced mir17-92 expression cooperates with c-myc and accelerates tumor growth by repressing cell death. These findings provided some of the first functional evidence that changes in miRNAs could contribute to oncogenesis. The work described in this application continues my studies on the oncogenic effects of mir17-92 using both cell culture systems and animal tumor models. First, I propose to identify the oncogenic miRNA components within the mir17-92 cluster, and to dissect the molecular basis for the tumorigenic effects of mir17-92. Second, the effects of mir17-92 in tumor maintenance and therapy response will be investigated. Finally, combined expression studies, copy number studies and functional characterization will be applied to examine more broadly the miRNA pathways in the oncogenic and tumor suppressor network. These studies, if successful, will produce fundamental insights into the functions of miRNAs during tumor development and tumor maintenance, which can be applied for discovery of both diagnostic markers and therapeutic targets.    

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99DA023700-01       

 

Program Director:

WU, DA-YU

Principal Investigator:

XU, XIANGMIN                     

PHD

Title:

Local Connections and In Vivo Physiology of Inhibitory Cortical Neurons

Institution:

SALK INSTITUTE FOR BIOLOGICAL STUDIES

LA JOLLA, CA

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant): Project Summary: Despite extensive knowledge of the basic blueprint of cortical circuits, detailed knowledge about the connectivity of specific cell types and how they function is still limited. The studies proposed here will investigate the laminar and fine-scale specificities of excitatory and inhibitory synaptic input to identified inhibitory neurons in the cerebral cortex, and will examine in vivo physiology of specific inhibitory cell types and their participation in regulating synchronous and oscillatory cortical activities. Recordings of specific inhibitory cell types can be facilitated by visualization of green fluorescent protein (GFP) expression restricted to known inhibitory neuron types in transgenic mice. Laminar specificity of functional input to specific cell types will be understood by using the technique combining whole cell recordings with scanning laser photostimulation. Furthermore, the fine-scale specificity of connections between pairs of neighboring inhibitory cells or excitatory and inhibitory cells will be revealed by cross-correlation analyses of synaptic responses evoked by photostimulation and recorded simultaneously from the neighboring pairs. In addition, to understand in vivo physiology and function of specific inhibitory cell types, targeted recordings under the guidance of 2- photon imaging will be made from these same cell types in GFP-expressing transgenic mice. We will record spikes from the target cells and measure local field potentials (LFPs) through electrocorticogram (ECoG) recordings. For each inhibitory neuron type, the overall spiking pattern in relation to LFPs and spike- triggered average of LFPs will be assessed to determine whether a correlative relationship exists between spike times and cortical oscillations. Other physiological properties of the recorded cells will also be assessed to further understand the properties of inhibitory neurons and their circuits. Relevance: Studies of the detailed organization of cortical circuits involving specific inhibitory cell types are necessary toward understanding cortical function. Understanding the specific roles of inhibitory cortical neurons has important implications for human health, as these cell types and their activities are involved in the cortical mechanisms that regulate attention and their disruption is implicated in schizophrenia.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99DE018088-01       

 

Program Director:

AVILA, ALBERT

Principal Investigator:

EBERHART, JOHANN                     

PHD

Title:

Genetic Hierarchies and Cellular Behaviors during Zebrafish Palatogenesis

Institution:

UNIVERSITY OF OREGON

EUGENE, OR

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant): There are hundreds of craniofacial diseases in humans and cleft palate is common among these. The goal of this proposal is to elucidate the signaling interactions and cellular behaviors underlying palatogenesis. The zebrafish provides a useful model system in which to study palatal development. Powerful genetic and cellular techniques are available in the zebrafish for studying gene function as well as cell and tissue signaling interactions. Additionally, the simplified palatal skeleton, consisting of far fewer neural crest palate progenitors than in mammals, and the optic clarity of the zebrafish embryo makes it ideal for analyzing cell behaviors occurring in palatogenesis. I propose to examine predictions of a reciprocal signaling hypothesis, in which signals from neural crest to the oral ectoderm and then back from the oral ectoderm to neural crest induce palatogenesis, and cause elongation of the palate through cell intercalations. In Specific Aim 1,1 examine the role of candidate genes for neural crest-derived signals and oral ectoderm response genes, turned on in the oral ectoderm. I use loss-of-function, gene expression, imaging, and genetic mosaic analyses to test the model that FgflO and Bmp4 signaling from the neural crest turns on pitx2 in the oral ectoderm, which, in turn, promotes palatogenesis. In Specific Aim 2,1 analyze the reciprocal signal, from oral ectoderm to neural crest. I use loss-of-function, imaging, and genetic mosaic analyses as well as construction of inducible transgenic zebrafish lines to test the prediction that Pdgf and ph/ephrin signaling from the oral ectoderm promotes palatogenesis. In Specific Aim 3,1 determine the cell behaviors that drive elongation of the palate. I use confocal time lapse analysis as well as cloning and characterization of novel zebrafish palate mutants to test the prediction that cell intercalations drive the extension of the zebrafish palate. The results I obtain during the course of these studies will shed light on the genetic and cellular causes of cleft palate. Additionally, two genes I propose to analyze, pitx2 and ephrin-B1, are known to be human craniofacial disease genes. Therefore, my analyses of these genes will provide direct insight into the cause of human disease.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99DK077427-01       

 

Program Director:

HYDE, JAMES F.

Principal Investigator:

SRINIVASAN, SUPRIYA                     

PHD

Title:

The Role of Serotonin in Energy Homeostasis in C. elegans

Institution:

UNIVERSITY OF CALIFORNIA SAN FRANCISCO

SAN FRANCISCO, CA

Project Period:

2007/07/01-2009/06/30

 

 

 

  DESCRIPTION (provided by applicant):  To ensure survival, animals must constantly assess food status in the environment, and respond appropriately by matching food intake to energy expenditure. The net balance between the two is reflected in the fat stores of the animal. The neurotransmitter serotonin plays a central role in maintaining this dynamic balance, by relaying food signals from the environment to elicit changes in behavior and physiology of the animal so that fat homeostasis is maintained. The goal of the research proposed here is to address the question: "How does serotonin signaling modulate energy balance in C. elegans?" I have identified a few key genes that are important for serotonin fat regulation in C. elegans. Using a combination of behavioral and physiological assays, I will examine the roles of these newly-identified genes in food intake and energy expenditure. Together with molecular and genetic analyses, I aim to specify the serotonergic network that couples food sensation to changes in feeding regulation and energy expenditure in C. elegans. My current research objectives are well-aligned with my long-term interest in understanding how the environment influences complex behavior and physiology at the organismal level. Understanding the complex intersection of genetics and environment is a frontier in the biological sciences with major, direct impacts on human health. The work proposed here lays the foundation upon which I will embark as an independent investigator at an academic research institution in the next two years. My current environment at the University of California-San Francisco under the mentorship of Dr. Kaveh Ashrafi and Dr. Keith Yamamoto, is ideally suited for my scientific and professional interests. The de-regulation of energy balance leads to obesity, a rising health concern world-wide. Indeed, current estimates suggest that more than 30% of Americans are obese, a condition that is a prime risk factor for cardiovascular disease, diabetes and reduced life expectancy. The ancient conservation of serotonin function in many species including mice and humans suggests that work proposed here will provide novel genetic targets for the study of body fat regulation.  

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99DK077445-01       

 

Program Director:

HYDE, JAMES F.

Principal Investigator:

ZHOU, QAIO                     

PHD

Title:

Diversity and Specification of Pancreatic Progenitor Cells

Institution:

HARVARD UNIVERSITY

CAMBRIDGE, MA

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant):  Progenitor cells are immature cell types that are responsible for constructing the entire organism during embryonic development as well as for replenishing and repairing tissues in adult life. Understanding progenitor cells is therefore a central question in biology. This problem applies to the pancreas, an organ of vital importance to human physiology because of the production of digestive enzymes and hormones such as insulin. The long term goal of this project is to understand the diversity and development of pancreatic progenitor cells in order to devise better strategies to treat pancreatic diseases such as diabetes.  In Specific Aim I of this proposal, we will determine the diversity of progenitor cells in the developing pancreas by a genome scale expression analysis to identify unique molecular markers that will mark each progenitor population. In Specific Aim II, we will determine the lineage of two specific pancreatic progenitor populations by genetic lineage tracing experiments with mutant mouse lines. In Specific Aim III, we will functionally test hypotheses of how transcription factors regulate the development of different progenitor cell types.  The proposed studies are expected to shed important light on the diversity and specification of pancreatic progenitor cells. A better understanding of the biology of pancreatic progenitor cells should aid efforts to derive functional endocrine cells for cell replacement therapies to treat diabetes. In addition, these studies may lead to greater insights into adult pancreatic progenitors that may be exploited for regeneration based therapy.  

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99DK077573-01       

 

Program Director:

HYDE, JAMES F.

Principal Investigator:

HOSTETLER, HEATHER A                    

PHD

Title:

The role of long chain acyl-CoAs in nuclear receptor regulation

Institution:

TEXAS A&M UNIVERSITY SYSTEM

COLLEGE STATION, TX

Project Period:

2007/04/01-2009/03/31

 

 

 

  DESCRIPTION (provided by applicant):  The peroxisome proliferator activated-receptor ( (PPAR() plays a central role in energy homeostasis by initiating transcription of multiple genes in fatty acid and glucose metabolism, while concomitantly downregulating genes in insulin signaling. In liver, PPAR( induces transcription of many genes involved in fatty acid degradation by (-oxidation, fatty acid uptake and transport, and lipoprotein metabolism. Thus, PPAR( is responsible for control of a number of lipid metabolic proteins that may contribute to obesity, diabetes, lipotoxicity, and subsequent cardiovascular disorders. However, relatively little is known regarding either the mechanisms that regulate the availability of endogenous fatty acyl-CoA ligands to the nucleus for interaction with PPAR( or the effect of these ligands on PPAR( interaction with heterodimer partners. Although it is known that PPAR( must heterodimerize with either the retinoid X receptor (RXR) or the liver X receptor (LXR) prior to binding DNA response elements, for transcriptional regulation, surprisingly little is known about the effect of endogenous ligands on the choice of heterodimer partners. Furthermore, the effect of PPAR( ligands on heterodimer partners is incompletely resolved. In order to address these issues, this proposal is focused in two phases: First, the 'mentored phase’will: 1. Resolve whether PPAR(-mediated transcription of genes is regulated by long-chain fatty acyl-CoAs (LCFA-CoA). 2. Determine the effect of LCFA-CoA on the molecular interaction of PPAR( with L-FABP. Second, the 'independent phase’will: 3. Determine if LXR( binds LCFA-CoA with high affinity, in the physiological range of nuclear LCFA-CoA levels. 4. Elucidate the effect of LCFA-CoA on the molecular interaction of PPAR( with LXR(. It is hoped that the results of this work will provide a mechanistic role of LCFA-CoAs in nuclear receptor regulation.  Relevance to Public Health: This work aims at studying a protein whose abnormal expression/regulation is associated with obesity, diabetes, and cardiovascular disease. This research is a step towards the development of new methods and more efficient drugs for the treatment of such disorders.  

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99EB007129-01       

 

Program Director:

BAIRD, RICHARD

Principal Investigator:

ALLEN, MATTHEW J                    

MB, PHD

Title:

Increasing the Utility of Contrast Agents for MRI

Institution:

UNIVERSITY OF WISCONSIN MADISON

Madison, WI

Project Period:

2006/12/01-2007/11/30

 

 

 

  DESCRIPTION (provided by applicant):  The long-term goals of this proposal are to address critical barriers to progress in the field of contrast agent-enhanced magnetic resonance imaging (MRI). My plan to overcome these barriers is to increase the utility of lanthanide-based contrast agents. Efforts will be focused on the development of contrast agents for high field MRI and activatable agents that are physiologically viable. Mentored K99 Phase: The postdoctoral phase (aim 1) of the proposal will be carried out under the mentorship of Professors L. L. Kiessling and R. T. Raines at the University of Wisconsin-Madison. The K99 phase goal is to develop exquisitely sensitive MRI agents using polymeric hydroxypyridonate (HOPO)-based chelates. This training at the interface of chemistry and biology will provide expertise in conjugation chemistries, manipulation and characterization of macromolecules, and the synthesis of novel lanthanide chelators. The acquired knowledge will prove invaluable for completion of aims 2-4 and transition into a successful career as an independent scientist. Independent ROO Phase: In the independent phase (aims 2-4), aims 2 and 3 focus on the development of biologically responsive contrast agents for MRI. Aim 2 involves the development of a novel class of activatable agents using dendrimer chemistry that have a true zero-background state. Zero background enhancement would enable concentration-independent imaging, overcoming a major barrier to the clinical use of activatable agents for diagnostic purposes. The experiments described in aim 3 focus on modulation of the innersphere water coordination number of HOPO-based agents. The new agents will have advantages over similar poly(aminocarboxylate)-based agents due to differences in water exchange rate and number of innersphere water molecules. In aim 4, methods to stabilize Eu(ll) complexes from oxidation are proposed. Stable Eu(ll) complexes will enhance contrast at high field strengths filling the void where Gd(lll) complexes cease to be viable contrast agents because of long electronic correlation times. Relevance: This proposal has the potential to greatly improve public health through advancement of the diagnostic capabilities of MRI by overcoming current technological limitations. The proposed research may lead to the ability to diagnose diseases at the earliest stages where treatments are often more effective.    

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99EB007151-01       

 

Program Director:

BAIRD, RICHARD

Principal Investigator:

KARTALOV, EMIL P                    

PHD

Title:

Integrated Nanofluidic BioMEMS for Biomedical Diagnostics and Analysis

Institution:

UNIVERSITY OF SOUTHERN CALIFORNIA

LOS ANGELES, CA

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant):  Mentored section:  As part of the mentored project, the candidate would extend his published results of high-throughput multiantigen fluorescence microfluidic immunoassays (BioTechniques 40: 85-90) to more complex samples, such as human blood serum and plasma, thereby paving the way to portable microfluidic blood test systems.  Relevance:  Portable microfluidic blood tests would produce major savings in cost and time in modern biomedical diagnostics with concomitant savings in healthcare in general. Such systems would also use finger-prick amounts of sample, eliminating the need for phlebotomy and the danger of hematomas, as well as making blood tests more accessible to pediatric patients, particularly infants. Low costs and small amounts of sample would also mean more frequent and ubiquitous testing, resulting in earlier diagnosis and thus saving lives.  Independent research section:  The applicant has a detailed plan outlined further below and including microfluidic immunoassays for viral detection, nanodetector and microfluidics integration for portable diagnostic devices, devices for large-scale cellular screening, on-chip PCR machine for on-the-spot forensic analysis, nested bioarrays for nanomedicine chips, DNA intercalator-separator of unknown samples, and a microfluidic cellular transfector.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99EB007182-01       

 

Program Director:

BAIRD, RICHARD

Principal Investigator:

LIU, CHUNLEI                     

PHD

Title:

High Resolution Diffusion-Weighted Magnetic Resonance Imaging at 300-Micron Level

Institution:

STANFORD UNIVERSITY

STANFORD, CA

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant):  Diffusion-weighted imaging (DWI) and diffusion-tensor imaging (DTI) are important magnetic resonance imaging (MRI) tools with significant clinical utility. However, current available spatial resolution for DWI is typically around 2mm per pixel, which is substantially lower than the submilimeter resolution of anatomical MRI. Such low spatial resolution severely limits the ability of diffusion MRI in investigating white matter structure and integrity, for example. Ultra high field strengths and emerging applications of DWI and DTI in pediatric neuroimaging, small animal neuroimaging, surgical planning and neural fiber tractography have created a strong demand for 1) higher image spatial resolution and 2) larger number of diffusion gradient directions. The overall goal of this proposal is to develop and refine advanced image formation techniques and novel diffusion analysis models. Towards this end, we propose to employ an array of novel techniques including motion navigated multi-shot sequences, parallel imaging with multiple coils, at high (3T) and ultra high magnetic field strengths (7T). Inherent advantages are that multi-shot sequences allow for improved data acquistion schemes with better SNR and reduced artifacts, which also alleviates the problem of rapid signal decay; parallel imaging provides a method for shortening the total scan time and further reducing image artifacts, while ultra high field offers stronger SNR and T2* sensitivity at the expense of potential artifacts. Although the synergy of these techniques holds great potential for high resolution DWI and DTI, many technical challenges remain. The specific aims of this research are to meet these challenges by: 1) developing multi-shot DW sequences with efficient volumetric imaging with 3D motion navigation and ; 2) developing multi-shot parallel imaging acquistion techniques and fast image reconstruction algorithms that can efficiently and rapidly post-process thousands of images in a clinical setting, and finally; 3) measuring higher order diffusion tensor parameters to resolve multi-modal white matter structures. These advanced techniques will not only allow better visualization and quantitation of in vivo water proton diffusion processes on the scale of a few hundred microns, but will also significantly improve the quality and speed of the image acquistions. These techniques will eventually result better diagnostic potential for diffusion-weighted images, and, ultimately, more accurate quantification of complex tissue diffusion properties.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99ES015426-01       

 

Program Director:

SHREFFLER, CAROL K

Principal Investigator:

NYLAND, JENNIFER F                    

PHD

Title:

Mercury exposure and the innate immune response in autoimmune heart disease

Institution:

JOHNS HOPKINS UNIVERSITY

BALTIMORE, MD

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant)   The overall goal is to demonstrate a link between mercury (Hg) exposure and elevated risks of autoimmune disease. In this project, the investigators will test two hypotheses in translational research linking basic research in an animal model of autoimmune disease and a pilot epidemiological study in a Hg-exposed human population in Amazonian Brazil. The hypotheses are that: 1) exposure of mice (adults and fetuses) to Hg, at low dose, can result in changes in the innate immune response to infection such that ultimately post-infection autoimmune disease is exacerbated in terms of severity and prevalence and 2) exposure of humans to Hg, at low dose, can result in changes in the immune system that are measurable and indicative of elevated risk of autoimmune dysfunction. Autoimmune diseases are among the most devastating chronic diseases in the US, affecting nearly 50 million people. While autoimmune diseases are generally recognized to involve both heritable and acquired risk factors, relatively little is known about the latter risks for human disease aside from exposure to infectious agents, such as viruses and bacteria. These infectious agents are believed to trigger the development of autoimmune diseases, but the expression and severity of disease may be a reflection of pre-existing genetic susceptibility. This project will assess programming changes that occur during the innate immune response to infection following exposure (either at adulthood or during fetal development) to Hg, with an overall effect on the progression of Coxsackie virus-induced autoimmune heart disease in mice and apply the biomarkers mined from the studies in animals to a Hg-exposed human population in Amazonian Brazil.   Specific Aim 1: To test the hypothesis that adult (murine) exposure to Hg induces changes in the innate immune response to Coxsackie virus infection, which result in exacerbation of subsequent autoimmune heart disease.   Specific Aim 2: To test the hypothesis that fetal (murine) exposure to Hg induces changes in the immune system that are long lasting and that these early events affect the innate immune response to Coxsackie virus infection and the subsequent development of autoimmune heart disease in adulthood.   Specific Aim 3: To test the hypothesis that human exposure to Hg induces changes in the immune system that are measurable and indicative of elevated risk of autoimmune dysfunction.    

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99ES015428-01       

 

Program Director:

SHREFFLER, CAROL K

Principal Investigator:

SABLE, HELEN J                    

PHD

Title:

Assessment of Psychostimulant Addiction Risk Following Developmental PCB Exposure

Institution:

UNIVERSITY OF ILLINOIS URBANA-CHAMPAIGN

CHAMPAIGN, IL

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant)   Relatively little is known about the effects of exposure to environmental contaminants on substance abuse risk. The goal of this project is to determine if developmental exposure to polychlorinated biphenyls (PCBs) enhances the predisposition to develop drug addiction using a rodent model. Recent theories propose that drug addiction occurs due to increasing incentive salience for the drug and drug-associated cues as well as impaired inhibitory control at the cognitive level. Research in animal models suggests that reduced dopamine (DA) activity in the medial prefrontal cortex (mPFC) may mediate this process. PCB exposure reduces brain DA and impairs mPFC-mediated cognitive functions. Based on these findings it is hypothesized that PCB exposure during early development will result in reduced DA function in mPFC, produce inhibitory control deficits and enhance the incentive salience of psychostimulants. The objectives of the current proposal are to: (1) characterize inhibitory control deficits and determine psychostimulant sensitivity in rats developmentally exposed to an environmentally relevant PCB mixutre and (2) determine whether PCB induced changes in DA receptor expression in the mPFC mediate both the enhanced psychostimulant sensitivity and the inhibitory control deficits. The specific aims of the mentored phase are to: (1) quantify differences in inhibitory control on a multiple fixed interval/extinction task, (2) measure changes in the expression of the dopamine transporter (DAT), vesicular monoamine transporter (VMAT2), D1, D2, and D4 receptor subtypes in the mPFC of rats developmentally exposed to PCBs relative to controls, and (3) determine if perinatal PCB exposure is associated with enhanced sensitivity to the discriminative stimulus or motor-activating properties of psychostimulants. The specific aims of the independent phase are to: (1) determine which DA receptor subtypes in the mPFC mediate the enhanced psychostimulant sensitivity and inhibitory control deficits in PCB-exposed animals, and (2) Determine whether developmental exposure to the polybrominated diphenyl ethers (PBDEs), ubiquitous environmental chemicals which are chemically similar to the PCBs, results in changes in DA receptor expression and enhanced psychostimulant sensitivity that parallel the effects produced by PCBs. The results will provide valuable information about substance abuse risk following developmental exposure to environmental contaminants that target the DA system.    

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99EY018042-01       

 

Program Director:

OBERDORFER, MICHAEL

Principal Investigator:

DING, LONG                     

PHD

Title:

Neuronal basis of reward-biased visual perception

Institution:

UNIVERSITY OF PENNSYLVANIA

PHILADELPHIA, PA

Project Period:

2007/01/01-2008/12/31

 

 

 

  DESCRIPTION (provided by applicant): The objectives of this Pathway to Independence Award for Long Ding, Ph.D., are to expand the candidate's expertise in the field of visual perceptual decision-making and to establish a novel experimental model to fill the knowledge gap on how visual perception is affected by reward-induced internal preferences. Achieving the first objective will complement the candidate's previous training in basal ganglia physiology related to learning and neural representation of reward. Achieving the second objective will provide a launching point for the candidate to develop an independent research career, toward a long-term goal of gaining a better understanding of the basal ganglia functions in reward modulation of perception. These objectives will be accomplished in two phases. In the 2-year mentored phase, the candidate will conduct supervised research in Dr. Joshua Gold's lab at the University of Pennsylvania to identify neural correlates of external evidence-based perceptual decisions in the basal ganglia and frontal cortex, using single-unit recordings in monkeys performing a visual motion discrimination task (Aim 1). This training environment is uniquely suitable because of Dr. Gold's expertise in visual perceptual decision-making, the immediate availability of well-trained monkeys and the intellectual resources available at Penn, which is renowned for its research on vision and perception. In the next 3-year phase, the candidate's independent research will identify neural correlates of decision-making that integrates reward-induced internal preference and external evidence in the basal ganglia and frontal cortex (Aim 2). This research will be based on single unit  recordings in monkeys performing a novel visual motion discrimination task that also incorporates reward bias. The proposed research is designed to test the central hypothesis that the neural representations of external evidence and reward-induced internal preference are co-localized and incorporated in individual neurons in the basal ganglia and frontal cortex. It represents an innovative merging of established lines of research and will advance our understanding of the neural mechanisms underlying normal visual perception. Relevance to public health: The proposed research represents an important research area of visual perception and will facilitate future identification of neural targets for better treatment of patients with perceptual impairment.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99GM079921-01       

 

Program Director:

OKITA, RICHARD T

Principal Investigator:

JONES, TONI I                    

PHD  PHARMACOLGY

Title:

Spinal Cord Signal Transduction in a Rat Model of Post-Surgical Pain

Institution:

UNIVERSITY OF CALIFORNIA SAN DIEGO

LA JOLLA, CA

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant): Post-operative pain is a major clinical concern, as it can delay patient recovery and increase probability of chronic pain syndromes. More than half of patients report moderate to severe pain after surgery, thus, it is important to investigate the mechanisms that generate and maintain this condition. Plantar incision in the rat hind paw is a model of post-operative pain resulting in spontaneous pain and hyperalgesia, or increased pain in response to stimulation, symptoms that are observed in patients. Spinal glutamate receptor pharmacology of this model is distinct. Spinally administered conventional antagonists to NMDA receptors have no effect on any aspect of incision-evoked pain in the rat. However, NR2B-NMDA and calcium-permeable AMPA/KA glutamate receptor subtypes appear to mediate separate aspects of post-operative pain behavior, although this is not certain. No studies have addressed the role of spinal signal transduction cascades occurring downstream from calcium-permeable AMPA/KA and NR2B-NMDA receptor activation after incision.   This application examines post-operative pain behaviors by targeting the facilitation of various elements of these cascades. Aim 1 will measure increases in incision-evoked activation of protein kinase A (PKA), conventional protein kinase C (PKC), and calcium/ calmodulin-dependent protein kinase II alpha (CaMKII alpha) over a 5-day period. Administration of selective kinase antagonists will demonstrate if these changes are necessary for the manifestation of pain behavior. Aim 2 will determine if pain behavior and/or CaMKII alpha activation are downstream of N-type calcium channel activation. Aim 3 will focus on events downstream of calcium-permeable AMPA/KA and NR2B-NMDA receptors. Receptor-specific antagonists will be administered to determine, if indeed, separate aspects of post-operative pain are diminished and, if so, whether each antagonist produces a distinct pattern of kinase inhibition. Aim 4 will measure phosphorylation of AMPA GLUR1 and NMDA NR1 and NR2B receptor subunits and AMPA GLUR1 receptor subunit insertion into the synaptic membrane after incision. These events are associated with synaptic strengthening and increased spinal sensitization. Treatment with calcium-permeable AMPA/KA and NR2B-NMDA receptor antagonists will be used to ascertain if these events occur downstream of receptor activation. Western blots and protein kinase activity assays will be used to measure activation and/or phosphorylation of specific agents. Subcellular fractionation combined with Western blots will be used to demonstrate receptor movement from cytosol to membrane, while immunohistochemistry in tandem with confocal microscopy will be used to determine cellular or regional localization of phosphorylated proteins. Delineation of these important spinal signaling mechanisms and identification of relevant receptor subtypes involved in post-operative pain will increase our ability to develop effective treatments for pain after surgery.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99GM079922-01       

 

Program Director:

OKITA, RICHARD T

Principal Investigator:

GARG, NEIL K                    

PHD

Title:

New Asymmetric Transformations and Chemical Synthesis of Natural Products

Institution:

UNIVERSITY OF CALIFORNIA IRVINE

IRVINE, CA

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant): This research program aims to develop new and efficient methods for the preparation of complex bioactive organic molecules. Research proposed in the K99 Mentored phase will be carried out over one to two years with Professor Larry Overman and involve the discovery of new asymmetric Pd(ll)-catalyzed reactions of allylic trichloroacetimidates. Pending the development of this methodology, it will be evaluated in the context of an efficient synthesis of microphyllaquinone, a small molecule that exhibits cytotoxicity against several cell lines. The R00 Independent phase (years 3 to 5) will focus on the discovery of an asymmetric metal-mediated coupling reaction to promote the formation of all-carbon quaternary stereocenters, a challenge often encountered in complex molecule synthesis. This powerful methodology will be expanded to include cascade reactions for the rapid construction of enantio-enriched fused and bicyclic ring systems beginning from simple, prochiral starting materials. Finally, the asymmetric total syntheses of two potent anti-inflammatory compounds, mangicols A and C, will be pursued.   If the goals of this proposal are achieved, new chemical methods for preparing biologically active molecules will be developed. Ultimately, this contribution will facilitate the discovery of new medicinal agents for treating human illnesses.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99GM079955-01       

 

Program Director:

RODEWALD, RICHARD D.

Principal Investigator:

SCHULDINER, MAYA B                    

PHD

Title:

Exploring Regulation of ER Homeostasis Using Quantitative Genetic Interaction Map

Institution:

UNIVERSITY OF CALIFORNIA SAN FRANCISCO

SAN FRANCISCO, CA

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant): My research interests focus on bridging the gap between systems biology and cell biology. My long-term goal is to couple my expertise in cell biology of the endoplasmic reticulum (ER) with high throughput tools and novel analytical methods to create a model for a self-contained unit within the cell. In the short term I plan to focus on the genes essential for maintaining homeostasis in the ER. The importance of a robustly functioning ER is underscored by its requirement for the normal development of multicellular organisms, especially differentiation of dedicated secretors such as plasma cells and insulin-secreting pancreas cells. To gain novel insights on maintenance of homeostasis in the ER, I propose to screen for all genes in whose absence the ER accumulates unfolded proteins. This can be measured accurately by utilizing a reporter for induction of the ER stress-induced unfolded protein response (UPR). Once all genes are identified, I plan to make a quantitative and accurate genetic interaction map, showing the extent by which a mutation in one of these genes changes the phenotype of all the others. Based on previous work, I believe that analysis of this map will allow me to predict functions for unknown proteins as well as organize all proteins into complexes and pathways. It will also allow me to study the hierarchy of the different processes involved in maintaining a fully functional ER. I propose to do this both in yeast (by using the yeast deletion strain library and a novel library of hypomorphic alleles of essential genes) and human cells (using RNAi technology). This comparison should allow me to define the evolutionary constraints leading to conservation of the organelle functions, thus developing a new understanding of the secretion process and its players in eukaryotes.   Summary: All secreted and membrane-bound proteins essential for cellular communication and reaction to the environment are first translocated into the endoplasmic reticulum (ER) where they fold and mature into their native conformations aided by a variety of folding enzymes. A change in conditions in the ER causes activation of a stress response that mediates return to homeostasis. Mutations causing this response to be overactive or underactive have been reported to play a role in diseases as varied as cancer, cystic fibrosis (CF), diabetes, neurodegeneration and heart disease. Thus, gaining a deeper understanding of the genes regulating homeostasis in the ER and the stress response will allow us to treat such human pathologies.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99GM079960-01       

 

Program Director:

CARTER, ANTHONY D.

Principal Investigator:

LEE, TAE-HEE                     

 

Title:

Dynamics in Translation: the Role of Fluctuation in Protein Synthesis

Institution:

STANFORD UNIVERSITY

STANFORD, CA

Project Period:

2006/12/01-2007/11/30

 

 

 

  DESCRIPTION (provided by applicant): Translation, in vivo protein synthesis, is a vital process in maintaining cell life by producing enzymes performing almost every critical function in the cell including gene transcription, gene repair, protein synthesis, and protein folding/degradation. Understanding translation is essential in controlling cell function/life by offering ways to control enzyme production in the cell. The ribosome selects the correct transfer RNA (tRNA) based on mRNA(codon)-tRNA(anticodon) interaction to synthesize protein with the correct sequence. The selection is composed of two sub-steps--initial selection and proofreading. Candidate is currently trying to elucidate the mechanism of proofreading. During the initial selection, ternary complex of elongation factor Tu (EF-Tu), tRNA, and GTP delivers tRNA to the mRNA/ribosome complex. Only when codon matches with anticodon, EF-Tu hydrolyzes GTP and changes conformation to dissociate from the ribosome. Candidate hypothesizes that this recognition process (codon-dependent GTP hydrolysis on EF-Tu) is enabled by tRNA fluctuations, dynamics of which is determined by codon-anticodon interaction. Therefore, tRNA acts as a communication channel between the ribosome decoding site and EF-Tu. To examine the hypothesis, candidate proposes to monitor individual working ribosome in real-time through single molecule fluorescence measurement. Single molecule measurement enables high time-resolution real-time monitoring of individual steps in non-synchronizable multi-step enzymatic processes.   Candidate proposes following specific aims to test the hypothesis: (1) Construct an experimental system to monitor tRNA movement, elongation factor Tu (EF-Tu) movement, and GTP hydrolysis through single molecule fluorescence resonance energy transfer (SM FRET): (a) achieve 3 ms time resolution to monitor the dynamics, (b) label EF-Tu and test fluorescent GTP analogues to monitor EF-Tu movement and GTP hydrolysis; (2) Achieve the highest possible signal-to-noise ratio (S/N) for SM FRET measurements: (a) optimize instrumentation for highest possible S/N, (b) optimize oxygen scavenger system, (c) Implement noise removal algorithm based on stochastic prediction; (3) Relate tRNA motion to GTP hydrolysis and EF-Tu dissociation: (a) monitor GTP hydrolysis and tRNA motion simultaneously, (b) monitor EF-Tu movement and tRNA motion simultaneously. Successful completion of proposed research will greatly enhance our understanding of in translation. Understanding how the translation machinery synthesizes proteins with such an unusually high accuracy will open ways to control cell function/life.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99GM080099-01       

 

Program Director:

CARTER, ANTHONY D.

Principal Investigator:

SONG, YUN S                    

PHD

Title:

Novel Methods for Characterizing Recombination and Selection

Institution:

UNIVERSITY OF CALIFORNIA DAVIS

DAVIS, CA

Project Period:

2006/12/01-2007/11/30

 

 

 

  DESCRIPTION (provided by applicant): Two known types of meiotic recombination are crossovers and gene conversions, which have different effects on the pattern of linkage disequilibrium (LD). Efforts to deduce patterns of historical recombination are central to the design and analysis of disease association studies, which depend on understanding the structure of LD in population data. The focus of the PI's current research is on developing efficient algorithms for reconstructing parsimonious evolutionary histories with recombination. The PI's long-term objective is to characterize quantitatively the effect of various evolutionary forces on shaping the structure of LD in the human genome. Some motivations for the proposed research are as follows: (1) Gene conversion has been hard to study in populations because of the lack of analytical tools and the lack of fine-scale data. However, genomic data produced over the next several years should allow quantification of the fundamental parameters of gene conversion, and the contribution of gene conversion to the overall patterns of sequence variations in a population. (2) Natural selection is an important evolutionary force that shapes genomic variation within species and the divergence between species. It has been shown recently that the patterns of LD generated by strong positive selection can resemble that generated by crossover hotspots.   The specific aims of the independent phase of the award are:  (1) Develop novel statistical methods for estimating crossover and gene conversion rates. A mathematical framework based on diffusion approximation will be used to obtain novel multi-locus sampling distributions. Gene conversion will be included in that framework. A likelihood method that utilizes the new sampling distributions will be developed to enable joint estimation of crossover and gene conversion rates.  (2) Study the effects of natural selection on the pattern of LD. The interaction of selection at multiple loci will be studied analytically and the structure of LD shaped by interacting selection will be characterized.   Relevance: Understanding the structure of variation in the human genome is central to the study of the genetic basis of disease risk and variation in drug response. The aim of this research, which is relevant to disease association studies, is to characterize various evolutionary mechanisms that shape the pattern of non-independence of genetic forms at different positions in the genome.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99HD055030-01       

 

Program Director:

HUANG, TERRY T-K

Principal Investigator:

TAMASHIRO, KELLIE L                    

PHD

Title:

Influences of the prenatal environment on metabolic programming

Institution:

JOHNS HOPKINS UNIVERSITY

BALTIMORE, MD

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant): Obesity is a major public health problem worldwide and recent work has suggested that exposure to a suboptimal early environment may increase the risk of becoming obese. Epidemiological data show that an unfavorable intrauterine environment has long-term consequences in offspring including hypertension, cardiovascular disease, type 2 diabetes, obesity and neuropsychiatric disease. Specifically, prenatal stress and/or consumption of a high fat diet, characteristics of modern day human lifestyle, have been shown to lead to metabolic disorders such as obesity and insulin resistance in offspring. However, the mechanisms involved are not well understood. The overall goal of this proposal is to characterize the short- and long-term effects of changes in the prenatal environment - stress and nutrition - on the behavioral and physiological development of offspring and to explore the possible neuropeptide and epigenetic mechanisms involved using a rat animal model. Specific aims are: 1) To determine the developmental time course of behavioral and endocrine alterations resulting from prenatal stress. We will also test the hypothesis that prenatal stress will accentuate diet-induced obesity. Time points during lactation, adolescence, and adulthood will be examined to characterize the phenotype and to direct examination of possible mechanisms; 2) To test the hypothesis that prenatal stress, high fat diet, or both result in alterations in neuropeptide systems regulating energy homeostasis that are consistent with other rodent models of obesity; and 3) To test the hypothesis that prenatal stress and nutrition results in obesity in offspring through epigenetic modifications via differential DNA methylation of genes that are critical to energy homeostasis. These experiments will enhance our understanding of the etiology of obesity and metabolic disease ultimately allowing the development of rational clinical interventions for such conditions. This proposal has also been structured to provide a rich and diverse training opportunity. The trainee has assembled a mentoring committee that will provide expertise in the development and regulation of ingestive behavior (Dr. Timothy Moran), neurobiology of stress and the hypothalamic-pituitary-adrenal axis (Dr. James Koenig) and the role of epigenetics in the etiology of disease (Dr. Andrew Feinberg and Dr. James Potash). The guidance of this committee in conjunction with the trainee's previous work in behavioral and molecular neuroendocrinology, will provide a solid foundation for the trainee to develop a multi-disciplinary program of research including behavioral, physiological, cellular/molecular, and genetic/epigenetic studies that will facilitate her transition to an independent investigator.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99HD055033-01       

 

Program Director:

HAVERKOS, LYNNE

Principal Investigator:

SLATER, SANDY J                    

PHD

Title:

Is the Built Environment Associated with Youth Physical Activity and Weight?

Institution:

UNIVERSITY OF ILLINOIS AT CHICAGO

CHICAGO, IL

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant): Sandy Slater, Ph.D., Research Specialist at the University of Illinois at Chicago (UIC) is a health policy analyst whose research focuses on the impact of state and local policies, and other environmental factors on health behavior. Specific to this application, Dr. Slater plans to study how the built environment and related policies influence adolescent physical activity and ultimately overweight and obesity. She will do this by drawing upon multiple theories and analytic techniques rather than limiting her research to only one discipline, while also seeking a permanent academic position in either the field of urban planning or public health. She plans to conduct this research at the UIC Institute for Health Research and Policy (IHRP). The work at IHRP spans social and behavioral health research, from basic science (including methods and theory development) and intervention development, to clinical and efficacy trials, research-to-practice and practice-to-policy translation, and dissemination. Under the mentored phase, she will complete two analyses using existing data that study the association between youth active travel, physical activity, overweight and obesity and a variety of built environmental measures. The results of these analyses will then be used to inform and guide the development of a pilot project for the independent scientist phase of this award. In addition, both the mentored and independent research plans will allow for the utilization of multi-disciplinary analytic skills and techniques to be acquired in the mentored phase of this award. For the independent phase, Dr. Slater proposes to develop and initiate a pilot project to examine the importance of school and community physical activity settings and opportunities on youth physical activity levels, overweight and obesity. The proposed study will combine detailed individual and parental survey data of Kindergarten, 3rd grade, and 5th grade students with community-level built environmental and related policy data, and school-level measures. The intent of the study is to examine the direct impact of individual and contextual factors on measures of BMI and overweight status, as well as their indirect influence on these outcomes via their effect on intermediary behaviors related to physical activity behaviors. The results of the pilot will then inform a larger R01 application. The results from a large-scale empirical study could then inform community-based interventions to reduce adolescent obesity.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99HD055034-01       

 

Program Director:

HENKEN, DEBORAH

Principal Investigator:

TANEYHILL, LISA A                    

PHD

Title:

Functional Roles of Wnt and Snail2 Target Genes in Neural Crest Development

Institution:

CALIFORNIA INSTITUTE OF TECHNOLOGY

PASADENA, CA

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant): The general theme of the candidate's research career has been to determine the molecular basis by which the Wnt signaling pathway activates expression of target genes and subsequently affects the generation of a particular cell type, in a context-dependent and temporal manner. The Wnt signaling pathway and its components are used reiteratively throughout embryonic development and in mature tissues during the transformation of normal cells to cancerous ones, demonstrating the importance of this pathway. Wnt signaling plays a significant role in the development of the neural crest, a population of migratory cells that helps pattern the embryo. Because of its contribution to embryonic structures, defects in neural crest development give rise to multiple syndromes, diseases, and cancers, including Axenfeld-Rieger, DiGeorge, and Treacher-Collins syndromes, and neurofibromatosis. To further understand how Wnt signaling regulates neural crest development, the candidate has performed a screen to identify novel targets of Wnt signaling involved in this process. Furthermore, investigation into the role of known Wnt target genes, such as Snail2 (Slug) allows her to elucidate how Snail2 regulates expression of its molecular targets in the context of neural crest development. Embryological and biochemical methods will be employed to determine the functional significance of these targets and their mode of regulation by Wnt. Overall, these approaches will provide her with a group of candidate molecules that will likely function in the generation of structures derived from the neural crest, such as the craniofacial skeleton and peripheral nervous system, as well as provide insight into the development of neural crest-derived cancers. In summary, the candidate's long-term research and career objectives include conducting mentored research (in the final years of her postdoctoral training) and independent research (as a principal investigator) to elucidate the molecular mechanism underlying Wnt signaling during the development of the neural crest, and applying this knowledge to human development as a whole. This research is relevant to public health because of the biological significance of the neural crest to the proper formation of human bodies, such as the bones of the face, nerves, and skin pigment cells. How neural crest cells properly become such diverse structures can help us comprehend what happens when neural crest development is impaired, and human syndromes and cancers arise.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99HD055052-01       

 

Program Director:

TASCA, RICHARD J

Principal Investigator:

CHEN, XIN                     

PHD

Title:

Epigenetic Regulation of Germ Cell Differentiation from a Stem Cell Lineage

Institution:

STANFORD UNIVERSITY

STANFORD, CA

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant): The mechanisms that regulate differentiation of cells from undifferentiated precursors play key roles in development, adult tissue maintenance, and gametogenesis. Precursor germ cells must commit to differentiate at the right place and with the right timing to generate or maintain the pools of functional gametes. The maintenance of the precursor germ cells in an undifferentiated and proliferative state and the subsequent reversal of these controls to allow terminal differentiation are both critical to continuous production of gametes throughout lifetime. The candidate is using the differentiation of Drosophila male germline cells from an adult stem cell lineage as a model system to investigate the roles of epigenetic control of cell-type specific transcription programs. She discovered that developmentally programmed expression and action of testis specific TAP (TBP-associated factors) homologs are responsible for expression of spermatid differentiation genes by counteracting the Polycomb transcription repressor. She now proposes to investigate the roles and regulation of Polycomb group (PcG) machinery and epigenetic chromatin modifications in precursor germ cell proliferation versus terminal differentiation. These studies have significant implications for reproductive biology, since the increasing evidence demonstrates conserved mechanisms that regulate spermatogenesis between flies and mammals. In addition, uncontrolled proliferation at the expense of differentiation leads to cancer, and PcG proteins have been implicated in both precursor cell fate and tumorigenesis, for example, in mammalian hematopoietic cells. Thus the studies will also shed light on the molecular mechanisms of cancer progression and treatment. The candidate's future work will use a combination of molecular, genetic, and biochemical strategies to explore the molecular mechanisms underlying a dramatic epigenetic switch, visualized by changes in level and/or localization of a set of covalently modified histones and chromatin modifiers at the precursor-to-differentiation transition during spermatogenesis.   The candidate's immediate career goal is to obtain a tenure-track faculty position in an academic environment after her postdoctoral training. Her ultimate research plan is to understand fundamental biological questions about the mechanisms that regulate proliferation versus cellular differentiation during male germ cell development. The candidate is committed to the research in biomedical science, and to the education of future scientists.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99HG004183-01       

 

Program Director:

SCHLOSS, JEFFERY

Principal Investigator:

SCHROEDER, CHARLES M                    

PHD

Title:

Single Molecule Technology for Genome-Wide Association Studies

Institution:

HARVARD UNIVERSITY

CAMBRIDGE, MA

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant): The candidate is a postdoctoral fellow in the laboratory of X. Sunney Xie at Harvard University and has been trained in single molecule polymer physics. The candidate's long-term scientific research goal is to study fundamental processes in biological systems and to develop new technologies based on single molecule tools for genomics, disease diagnosis, and biotechnology. The NIH PI Award will facilitate the candidate's career development by providing training in protein expression and purification, benchtop biochemistry, enzymology, and single molecule fluorescence imaging. Harvard University has a vibrant single molecule research community and will provide an excellent training environment for the candidate. The overarching goal of this research program is to develop novel single molecule technologies for advancement of human health. The specific goal of the current research proposal is to develop a single molecule technology for conducting genome-wide association studies for complex diseases in a low-cost, high-throughput format. Identification of genes associated with common diseases will lead to a major breakthrough in our understanding of the causes of human disease and will catalyze a new paradigm for diagnosis of diseases, prediction of drug response, and development of new disease therapies. The goal of this research proposal will be achieved by addressing the following specific aims: 1.) Demonstration of a high-throughput method for analyzing stretched and trapped genomic DNA molecules using a microfluidic device; 2.) Development of molecular tags for sequence-specific marker recognition in genomic DNA; 3.) Linking of fluorescent probes to these molecular tags; 4.) Development of methods for extraction and manipulation of intact genomic DNA from cells in a "lab-on-a-chip" format. The proposed single molecule-based technology will deeply impact human health by providing a cost efficient method for genotyping appropriate for routine clinical diagnoses. Specifically, the new technology will facilitate identification of genes that contribute to complex diseases, guide the fast and early diagnosis of diseases, allow for targeting specific proteins encoded by identified genes during drug development, and allow small molecule drugs to be prescribed based on individual genomic content. In short, the proposed single-molecule based genotyping technology will catalyze the start of the era of personalized medicine.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99HL087462-01       

 

Program Director:

VARGHESE, JAMIE

Principal Investigator:

TIKUNOVA, SVETLANA B                    

PHD

Title:

Influence of Troponin C on the Rate of Cardiac Muscle Relaxation

Institution:

OHIO STATE UNIVERSITY

COLUMBUS, OH

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant):   Up to 40% of heart failure patients have impaired relaxation, known as diastolic dysfunction. Cardiac  muscle relaxation is not merely a passive reversal of contraction, but a complex process requiring a series of events: 1) decline in intracellular Ca2+, 2) dissociation of Ca2+ from troponin C (TnC), and  3) cross-bridge detachment. There is controversy regarding the relative importance of each of these events in controlling relaxation. Despite the fact that Ca2+ must dissociate from the regulatory domain of TnC to allow relaxation, contribution of TnC to the rate of relaxation is in dispute. The objective of this project is to test the overriding hypothesis that the rate of Ca2+ dissociation from the regulatory domain of TnC is a major determinant of cardiac relaxation. To test this hypothesis, the proposed study will utilize the following AIMs:   AIM 1: Elucidate and manipulate factors controlling Ca2+ binding and exchange with TnC in increasingly structured systems, ranging from isolated TnC to reconstituted thin filaments. The goal of this aim is to determine how Tnl, thin and thick filament proteins and key residues in TnC affect Ca2+ affinity and Ca2+ dissociation rate from the regulatory domain of TnC. TnC proteins, generated in this AIM by mutagenesis of key residues in TnC, will be used in AIMs 2 and 3 to test the overriding hypothesis.   AIM 2: Determine the contribution of Ca2+ dissociation from TnC to the rate of relaxation in skinned rabbit trabeculae. This study will probe the contribution of Ca2+ dissociation from TnC to the rate of relaxation at the level of the myofilaments. Relaxation of skinned trabeculae reconstituted with TnC mutants, possessing dramatically faster or slower Ca2+ dissociation rates, will be induced by rapid laser photolysis of the caged Ca2+ chelator diazo-2.   AIM 3: Determine the contribution of Ca2+ dissociation from TnC to the rate of relaxation in intact, continuously contracting rabbit trabeculae in culture. These studies will probe the contribution of TnC to the rate of relaxation, under the conditions where Ca2+ sequestration can be a determinant of relaxation. TnC mutants with dramatically faster or slower Ca2+ dissociation rates will be introduced into intact cultured trabeculae by adenoviral gene transfer.   These experiments should clarify whether TnC should be a target for the treatment of diastolic dysfunction. (End of Abstract)   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99HL087513-01       

 

Program Director:

VARGHESE, JAMIE

Principal Investigator:

MAHONEY, WILLIAM M                    

PHD  BIOCHEMISTRY

Title:

Molecular Characterization of Arterially-Restricted RGS5

Institution:

UNIVERSITY OF WASHINGTON

SEATTLE, WA

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant):   Arteries and veins must have very distinct properties responsible for each vessel's unique functional  demands. For example, arteries, unlike veins, transmit the pressure wave and constrict to maintain  pressure and to control blood flow. We propose that these different properties are regulated by a unique gene, or genes, found in arteries. We discovered that Regulator of G-Protein Signaling - 5 (RGS5), a member of the highly homologous R4 subfamily of RGS proteins, uniquely identifies smooth muscle cells (SMCs) from arteries relative to veins. The RGS family of proteins functions to control the duration of cellular signals mediated through G-Protein Coupled Receptors (GPCRs). RGS proteins act as GTPase Activating Proteins (GAPs) for specific GPCRs by facilitating the exchange of GDP for GTP upon G-alpha subunits of the heterotrimeric G-protein complex (Galpha/beta/gamma), thereby returning the complex to its inactive state. Our preliminary results demonstrate that arterial SMCs, relative to vein SMCs, specifically overexpress RGS5. In addition, arteries differentially express RGS5 (i.e., some arteries express RGS5 to a higher degree than others). Finally, RGS5 expression is dynamically regulated in response to vascular injury, and therefore, RGS5 may be dynamically regulated as cardiovascular disease develops.   Based on these preliminary data, we hypothesize that artery-specific differences - either in physical forces acting on each vessel segment or local factors such as cell lineage or in nervation - act through specific promoter sequences to determine RGS5 protein expression level. The proposed experiments will identify and characterize the expression mechanism controlling RGS5 expression in arteries. Specifically, the experiments proposed will: (1) characterize the transcriptional regulatory mechanism controlling RGS5 mRNA expression in vitro; (2) characterize the RGS5 promoter in vivo; (3) investigate the activity of RGS5 during development an in response to vascular injury; (4) use the RGS5 promoter as a molecular model to address larger pathophysiologic questions, focusing on the likely hypothesis that functional adaptation of arteries is determined by a coordinate control mechanisms for transcription of mRNA for proteins that are key to differential arterial function. The latter goal-defining the mechanism defining arterial gene expression in response to specific local demands-is intended to provide the basis for an independent research career. (End of Abstract)   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99HL087560-01       

 

Program Director:

ROTHGEB, ANN E.

Principal Investigator:

DESHPANDE, DEEPAK A                    

DVM, PHD

Title:

Molecular Mechanisms of Airway Smooth Muscle Relaxation

Institution:

WAKE FOREST UNIVERSITY HEALTH SCIENCES

WINSTON-SALEM, NC

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant):   Although inhaled beta-agonist is a first-line therapy for treatment and prophylaxis of acute bronchospasm that occurs with asthma, its mechanisms of action are poorly understood. In this Pathway to Independence application we propose of series of hypothesis-driven experiments, as well as the development of new approaches, to clarify mechanisms mediating airway smooth muscle (ASM) relaxation. The proposed studies will utilize both murine and human tissue and cells to explore mechanisms by which two relevant agents, beta-agonist and prostaglandin E2 (PGE2), mediate inhibition of ASM tension generation. Two sets of Specific Aims for the mentored and independent phases of this award are proposed. Mentored Phase I studies will provide important, new data establishing the relationship between regulation of calcium flux, contraction, and agonist-stimulated signaling events in both murine and human ASM. Independent Phase II studies will provide greater mechanistic insight into the Phase I outcomes by identifying the specific intracellular targets of beta-agonist signaling that antagonize calcium flux and contraction, and how modulation of these targets is influenced with chronic agonist treatment. Upon completion of Phase II studies, the PI should have both an empirical basis and powerful methodologies to pursue highly relevant research in the field of ASM physiology and biology. (End of Abstract)   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99HL087561-01       

 

Program Director:

COMMARATO, MICHAEL

Principal Investigator:

SILVA, RANASINGHE A                    

PHD

Title:

The Role of Apolipoprotein A-II in the Modulation of HDL Function

Institution:

UNIVERSITY OF CINCINNATI

CINCINNATI, OH

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant):   Cardiovascular disease (CVD) is the number one killer in the United States, taking nearly a million lives each year. It is well established that high density lipoprotein (HDL) and its major protein constituent apolipoprotein (apo) A-l play a major role in reducing the risk of CVD. However the function of apolipoprotein A-l I, the second most abundant protein in HDL, has not been determined. Studies on apoA-ll have led to mixed conclusions concerning the pro- or antiatherogenicity of apoA-ll in HDL. This study will test the hypothesis that apoA-ll interacts with apoA-l in HDL in a site-specific manner to modulate HDL function. Furthermore, the effect is based on the relative amounts of apoA-l: apoA-ll present in a given HDL particle. In the Mentored Phase of this project, I will determine how the incorporation of apoA-ll affects apoA-l structure in discoidal reconstituted HDL particles. Relative changes in the solvent accessibility of specific apoA-l sequences in mixed particles vs apoA-l only HDL will be assessed using the hydrogen deuterium exchange technique combined with mass spectrometry (HDX-MS). I will then extend the studies in the Independent Phase to locate conformational changes in apoA-l caused by apoA-ll in HDL particles from human plasma. This will be accomplished in stages. First, I will reconstitute spherical HDL particles that resemble native HDL by incorporating varying ratios of apoA-l:apoA-ll along with native HDL lipids. I will also generate native hybrid HDL particles by incorporating isolated apoA-ll into native HDL particles containing apoA-l only. The apoA-ll induced modifications of apoA-l solvent exposure will then be correlated to functional properties including activation of various HDL remodeling factors including lecithin:cholesterol acyl transferase (LCAT), hepatic lipase (HL), and endothelial lipase (EL). I anticipate that this work will provide significant new information on the role of apoA-ll in lipoprotein metabolism and may suggest new therapeutic approaches for fighting CVD. (End of Abstract)   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99HL087591-01       

 

Program Director:

COMMARATO, MICHAEL

Principal Investigator:

O'CONNELL, KRISTEN M                    

PHD

Title:

Cell Biology of Cardiac Kv Channels

Institution:

COLORADO STATE UNIVERSITY-FORT COLLINS

FORT COLLINS, CO

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant):   Kv channels play a crucial role in determining the resting membrane potential, shaping action potential repolarization and setting spike frequency. It is becoming increasingly clear that the subcellular localization of these channels is an important component of cellular excitability. However, very little is known; about the localization of specific ion channels within cardiac myocytes. Kv2.1 is one of the delayed rectifier K+ channels expressed in both atria and ventricle, where it plays an important role in the late phase of repolarization of the cardiac action potential and helps set the QT interval. Kv2.1 is unusual among the voltage-gated K+ channels in that its function is modulated by hypoxia/ischemia, redox, mitochondrial Ca2+ and muscarinic agonists. It is intriguing that channel localization is also altered by these stimuli, suggesting a tight relationship between channel function and localization. In the brain, the altered function of Kv2.1 following ischemic insult appears to be neuroprotective. It is therefore likely that Kv2.1 plays a similar role in the heart. The hypothesis of this proposal is that the localization of Kv2.1 to subcellular microdomains places the channel in proximity to the singaling pathways that modulate its function in response to cellular stimuli, permitting dynamic regulation of cardiac excitability on a beat-to-beat basis. Because it is unknown where in a cardiac myocyte Kv2.1 is expressed, the goal of the mentored phase of this proposal is to establish cardiac myocytes from both atria and ventricle as a model system for studying the trafficking of Kv2.1. AdenoviraI-mediated expression of tagged channels will be used to study the localization and dynamics of Kv2.1 in living myocytes, thus building a foundation for the independent phase research. During the second phase, the emphasis will be on investigating the role of Kv2.1 in the cardiac cellular response to ischemia and intracellular Ca2+. We propose that the localization of Kv2.1, and consequently channel function will be altered by these stimuli. Idiopathic arrhythmias and cardiac ischemia are serious threats to human health whose underlying causes are not well understood. Therefore, defects in ion channel localization may be an as-yet unrecognized cause of human cardiac disease, emphasizing the importance of understanding how these proteins are trafficked and localized in the heart.  (End of Abstract)   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99HL087607-01       

 

Program Director:

VARGHESE, JAMIE

Principal Investigator:

WANG, MEIJING                     

MD

Title:

Testosterone in TNFR1 Signaling During Acute Myocardial Injury

Institution:

INDIANA UNIV-PURDUE UNIV AT INDIANAPOLIS

INDIANAPOLIS, IN

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant):   Myocardial ischemia is a leading cause of heart failure and death in both men and women. Restoration of blood flow to ischemic myocardium results in ischemia / reperfusion (I/R) injury. Sex-specific differences have been noted in myocardial I/R. Clinically, when compared to women, men experience: a higher overall incidence of heart failure, more rapid heart failure progression, worse age-matched cardiac contractility, and less preservation of myocardial mass as they age. These differences may be attributable to the effects of the sex hormone testosterone. Surprisingly, little information exists regarding the effect of testosterone on myocardial injury. Myocardial inflammation occurs following cardiac I/R injury and plays a crucial role in myocardial dysfunction. Tumor necrosis factor-alpha (TNF) is increased in myocardial tissue following I/R, and contributes to post-ischemic myocardial dysfunction, proinflammatory signaling and myocyte apoptosis. The effect of testosterone on TNFR1 and TNFR2 signaling following myocardial I/R remains unknown. Nearly simultaneously, ischemia results in the activation of JAK/STAT and p38 MARK signaling pathways, both of which are responsible for subsequent inflammatory cytokine production and apoptosis. Suppressors of cytokine signaling (SOCS) proteins, that are induced by various cytokines and stresses, exert negative effects on cytokine production and apoptosis. It remains unknown whether cross talk exists between the STAT/SOCS pathway and TNFR1 or TNFR2 signaling in the heart, and if so, whether testosterone amplifies  or suppresses this link following myocardial I/R. A therapeutic approach to the treatment of heart failure  may be to unbalance TNF signaling to diminish its deleterious effects while enhancing its salutary effects, towards a therapeutic benefit for both sexes. Utilizing endogenous mechanisms, such as SOCS mediated disruption of TNFR1 signaling, is appealing. We hypothesize that: 1) testosterone exacerbates acute myocardial ischemia and reperfusion injury by unbalancing TNFR1/TNFR2 signaling in favor of TNFR1; and 2) testosterone does so by disrupting the SOCS-3/STAT3 regulatory balance of TNFR1 signaling in the heart. Several specific aims are proposed to test these hypotheses which will be accomplished within the context of a detailed training plan, with the ultimate goal being a repeatedly-funded independent investigator at the faculty level. (End of Abstract)   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99HL087614-01       

 

Program Director:

VARGHESE, JAMIE

Principal Investigator:

ENNIS, DANIEL B                    

PHD

Title:

Myocardial Structure, Function, and Remodeling in Mitral Regurgitation

Institution:

STANFORD UNIVERSITY

STANFORD, CA

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant):   The clinical consequence of severe, uncorrected mitral regurgitation (MR) is excess mortality and morbidity. The timing of surgical intervention in chronic MR remains one of the most challenging clinical decisions in cardiac surgery. A refinement in our understanding of the pathogenesis of ventricular remodeling in mitral regurgitation is clearly needed to improve clinical outcomes. The canonical model of ventricular remodeling in volume overload hypertrophy does not account for transmural differences in hypertrophic remodeling. We now have exciting preliminary results that demonstrate a transmural gradient in ventricular wall remodeling wherein the epicardium thins by 30% and the endocardium thickens by nearly 10% during chronic MR. The overall hypothesis of the work is that transmural differences in the hypertrophic response to chronic mitral regurgitation may portend a poor clinical outcome. My immediate career goal is to develop the necessary experimental, computational, and theoretical tools to test hypotheses about transmural differences in cardiac  structure, function, and remodeling in mitral regurgitation. A unique research environment is available to me through an inter-disciplinary collaboration between the Departments of Cardiothoracic Surgery and  Radiology at Stanford University. This opportunity affords the ability to gain a deep understanding of cardiac pathophysiology research in addition to further developing my expertise in cardiac magnetic resonance imaging. My career plan includes gaining considerable expertise in experimental cardiac physiology research, quantitative histologic methods, diffusion tensor magnetic resonance imaging (DTMRI), and computational techniques for integrating structure and function data. My long-term career goal is to secure a tenure-track faculty position so that I can continue to answer questions about cardiac structure, function, and remodeling in disease. Work during the Independent Phase will develop the first finite element model of integrated cardiac structure and function from a rodent model of mitral regurgitation using data acquired from MRI tissue displacement and DTMRI. The relevance of this research proposal regards improving our understanding of mitral regurgitation, a common cause of heart failure. The results of this research may help elucidate important changes that underlie the progression from chronic mitral regurgitation to over heart failure and may spur the development of innovative therapies to aid in the treatment of this disease. (End of Abstract)   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99HL087618-01       

 

Program Director:

SARKAR, RITA

Principal Investigator:

MOSNIER, LAURENT OLIVIER                    

 

Title:

Direct Cellular Effects of Blood Coagulation Proteases

Institution:

SCRIPPS RESEARCH INSTITUTE

LA JOLLA, CA

Project Period:

2006/12/01-2007/11/30

 

 

 

  DESCRIPTION (provided by applicant):   The major scientific goal of this Pathway to Independence (K99/R00) Career Development Award application is to understand the molecular pathophysiology of thrombotic and inflammatory disorders by studying novel mechanisms for cytoprotective actions of vitamin K-dependent coagulation proteases. This application focuses initially on the role of membrane receptors in the regulation of the cellular protein C pathway and later on the exploration of novel mechanisms for cytoprotective activities of coagulation proteases. The major career development goal of the applicant is to expand his technical and academic experience required for a successful transition into an independent investigator. These studies will provide the opportunity and solid basis to apply successfully for future independent NIH R01 funding focused on the molecular mechanistic  studies centered on the crossroads of coagulation and inflammation. Novel hypotheses on the functional proteomics of cytoprotective actions by blood coagulation proteases will be tested using biochemical and cellular biology methods. The clinical and therapeutic implications of the proposed studies are clear from the large clinical trials, where activated protein C (ARC), but not other anticoagulants reduced mortality in severe sepsis patients and implied that the unique combination of APC's anticoagulant activity and direct activity on cells is the basis for APC's success. My published work and unpublished preliminary data lead directly to the proposed studies and provide strong support for my hypotheses. In testing these hypotheses, I propose: 1) To characterize the formation of endothelial cell membrane receptor complexes between thrombomodulin,  endothelial protein C receptor and protease activated receptor-1 required for APC generation and APC's direct effects on cells; 2) To clarify the potential beneficial and detrimental functional properties of platelet factor 4 for APC generation and APC's direct effects on cells; 3) To identify novel themes and mechanisms for APC and fVlla cytoprotective actions on cells by exploration of the similarities and differences between APC and fVlla anti-apoptotic activities; and 4) To establish whether meizothrombin has anti-apoptotic activity, as predicted, and if this activity requires cofactor-dependent and PAR-dependent mechanisms. If the proposed studies are successful, they will increase our knowledge and may lead to improved treatment of a variety of disorders in which thrombosis, apoptosis and inflammation contribute to pathogenesis. (End of Abstract)     

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99HL087621-01       

 

Program Director:

VARGHESE, JAMIE

Principal Investigator:

GRIFFIN, COURTNEY T                    

PHD

Title:

ATP-Dependent Chromatin-Remodeling Complexes and Vascular Development

Institution:

UNIVERSITY OF NORTH CAROLINA CHAPEL HILL

CHAPEL HILL, NC

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant):   ATP-dependent chromatin-remodeling complexes are thought to play important roles in a number of  developmental processes. We propose to ablate the catalytic subunits of the three best-known classes of mammalian chromatin-remodeling complexes in mouse endothelium in order to understand their influence on vascular development. Our preliminary data indicate that at least one class of these complexes (SWI/SNF) is necessary for normal vascular development and for embryonic viability. We also propose strategies for identifying genomic targets of these complexes that might mediate their activities during vascular development. We believe these studies will clarify the role of epigenetics in vascular morphogenesis and will lead to the discovery of new genes and signaling pathways involved in vascular development.   This Award will advance the candidate's goal of establishing an independent lab for the study of vascular development. The mentor's lab provides a rich environment for learning techniques necessary for the discovery of target genes of chromatin-remodeling complexes in the developing vasculature. The candidate will identify such targets in a mouse endothelial cell line during the mentored phase of the Award and will verify those targets in mice lacking vascular chromatin-remodeling complexes during the independent phase of this Award. Additionally, the candidate will refine techniques for the phenotypic analysis of SWI/SNF deficient embryonic vasculature during the mentored phase of this Award, which will be useful while evaluating embryonic vasculature deficient for the two other classes of chromatin-remodeling complexes during the independent phase of this Award.   Many of the processes that occur during vascular development in the embryo are recapitulated when  new blood vessels are formed in the adult. New vessel formation can be beneficial (e.g., during wound  healing) or detrimental (e.g., during tumor growth) in the adult. Therefore, this project provides an important approach to defining genes that could lead to novel therapies to promote insufficient vascular growth or to disable pathogenic vascular growth. (End of Abstract)   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99HL087927-01       

 

Program Director:

COMMARATO, MICHAEL

Principal Investigator:

NORTHCOTT, CARRIE A                    

PHD

Title:

Paraventricular Nucleus Signaling Mechanisms in Hypertension

Institution:

MICHIGAN STATE UNIVERSITY

EAST LANSING, MI

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant):   My career goal is to have an independent research laboratory exploring the direct neuronal signaling  pathways in the paraventricular nucleus (PVN) that influence hypertension. The PVN is an integrative region of the hypothalamus involved in the regulation of metabolic processes, stress responses, cardiovascular function/blood pressure regulation and the autonomic nervous system. The overall hypothesis is that sodium-dependent hypertension is associated with increased excitatory neurotransmission and hypertension that is the result of changes within the PVN. In part due to altered paracrine signaling, specifically nitric oxide (NO) and superoxide (O2-) interactions, influencing neurotransmitters. In addition, an upregulation of intracellular signaling families, phosphatidylinositol  3-kinase (PI3-kinase) and mitogen activated protein kinase (MARK), further amplifies excitatory neurotransmission resulting in hypertension. The goal is to use an integrative approach, using biochemical, gene transfer and physiological studies, to examine how both paracrine and intracellular signaling changes in the PVN to increase excitatory sympatho-adrenal function and elevate blood pressure. To achieve this goal 4 hypotheses will be addressed (2 during the mentored period and 2 during the independent portion of the grant): Hypothesis #1: NAD(P)H oxidase is present in the PVN and its activity is increased by Ang II and glutamate, thus elevating O2- levels in renal wrap hypertension. Hypothesis #2: In renal wrap hypertension, there is elevated O2- which combines with NO, reducing bioavailable NO and ultimately increasing sympathoadrenal function and blood pressure. Hypothesis #3: Ang II via the AT1 receptor and Glutamate via the NMDA receptor utilize common signaling pathways involving an upregulated PI3-kinase signaling cascade, increasing O2-, in turn, elevating excitatory neurotransmission in hypertension. Hypothesis #4: Enhanced O2- levels act as signaling molecules that lead to the activation of the MAPK signaling cascade in the PVN, ultimately elevating excitatory neurotransmission in hypertension. Identifying the changes in paracrine and intracellular signaling pathways is significantly important for understanding the impact signaling pathways have on neurotransmitter activity and hypertension. In addition, due to the integrative nature of the PVN, these data will also provide a glimpse at the role of signaling in other physiological conditions, such as obesity. (End of Abstract)      

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99HL087936-01       

 

Program Director:

WERNER, ELLEN

Principal Investigator:

CHING-CHENG, CHEN                     

PHD

Title:

Paired lg-Like Receptor as a Regulator of Hematopoietic Stem Cell Function

Institution:

STANFORD UNIVERSITY

STANFORD, CA

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant):   Hematopoietic stem cells (HSCs) are a rare population of cells in blood forming tissues that can self-renew and differentiate into all blood cell lineages. The long-term objective of the candidate is to understand the underlying mechanisms and regulators of HSC fate decision and survival. We propose to study a pair of activating and inhibitory receptors named paired Ig-like receptors (PIRs) that are expressed in HSC. PIR-A (activating) and PIR-B (inhibitory) form a novel MHC class I recognition system that can constitutively regulate the activation threshold in cells that express them. PIR is involved in the regulation of cytokine, integrin, and chemokine receptor signaling pathways that are crucial for HSC and progenitor functions. Thus we hypothesize that PIRs are major regulators of hematopoietic stem cell self-renewal, migration and survival. Our preliminary findings have demonstrated that: 1) PIR expression is specifically regulated among hematopoietic HSC and progenitor cell subsets; 2) Perturbing PIR expression, using a lentiviral shRNA knockdown strategy, dramatically reduces HSC re-engraftment capability; 3) PIR-A knockdown HSCs display selective reduction in responsiveness to the CXCR4 ligand SDF-1a in in vitro chemotaxis assays; and  4) Knocking down PIR expression in mast cell and HSCs greatly alters their responses to SCF and  IL-3, cytokines important for their survival. Based on these observations, we plan first to investigate whether altering expression levels of PIRs or PIR ligands will influence HSC engraftment capacity. Then we will try to unravel the underlying mechanisms of how PIR regulate HSC functions. Lastly, we will determine the role of PIR, as the only known MHC recognition system expressed on HSC, in HSC engraftment resistance between MHC-match and allogeneic mouse strains.   Elucidating the roles of PIRs in the regulation of HSC function will increase our understanding of the underlying mechanisms controlling the proliferation and fate of HSCs. This knowledge is important for both understanding hematopoietic disorders and for the therapeutic use of HSCs. This award will provide the candidate two years of mentored and three years independent research in the field of stem and mast cell biology. Research collaborations and resources will assist the candidate in the development of the skills and autonomy required to become a successful independent investigator. (End of Abstract)   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99HL088000-01        

 

Program Director:

COLOMBINI-HATCH, SANDRA

Principal Investigator:

FUCHS, SEBASTIEN                     

MD, PHD

Title:

Importance of the Two Catalytic Sites of ACE in Bleomycin-Induced Lung Injury

Institution:

EMORY UNIVERSITY

ATLANTA, GA

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant):   Project Summary. The phenotype of angiotensin converting enzyme (ACE) knockout mice is a complex  combination of cardiovascular, reproductive, hematologic and renal defects. This diversity of abnormalities supports the idea that ACE and angiotensin II influence many physiologic processes beyond simple blood pressure control. ACE is a zinc metalloproteinase composed of two regions termed N- and C-terminal domains. These domains are highly homologous but have somewhat different properties. In particular, while both domains can cleave angiotensin I, the tetrapeptide AcSDKP is exclusively cleaved by the N domain. To investigate the in vivo roles of each domain, I created two new strains of mice. These mice were generated by homologous recombination in order to mutate the specific amino acids responsible for zinc binding (and thus catalysis) in each domain. In mice termed N-KO, the N-terminal domain of ACE is inactivated. In C-KO mice, it is the C-terminal domain that is no longer catalytic. The cardiovascular and renal phenotypes of N-KO and C-KO mice are indistinguishable from this of wild-type. These mouse models are ideal to study specific functions of ACE independent of blood pressure changes, a typical bias in studying the RAS with pharmacologic manipulations. My first aim is to complete the characterization of the C-KO mice. This investigation will be performed during the mentored phase of this grant. The next aims will be fully developed during the independent phase. The second aim is to investigate the in vivo function of the two catalytic sites of ACE in the progression of pulmonary fibrosis using bleomycin-induced lung injury as a model. My hypothesis is that ACE controls the concentration of both pro-fibrotic (angiotensin II) and  anti-fibrotic (AcSDKP) molecules. My preliminary data strongly suggest that the N-KO mice are protected against bleomycin-induced lung injury. I find this in studies using both low and high doses of bleomycin. The third aim is to identify the mechanism responsible of this resistance. My hypothesis is that AcSDKP, elevated in N-KO mice, inhibits the progression of lung fibrosis. Relevance: This proposal will yield fundamental knowledge about the importance of ACE and its multiple substrates in tissue injury. Finally, my studies are both interesting and relevant to a variety of human diseases, including diseases of the lung, heart and kidney. (End of Abstract)   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99HL088017-01       

 

Program Director:

PRATT, CHARLOTTE

Principal Investigator:

ROVNIAK, LIZA                     

PHD

Title:

WalkLink: Email-Based Walking Program for Cardiovascular Disease Risk-Reduction

Institution:

SAN DIEGO STATE UNIVERSITY

SAN DIEGO, CA

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant):   RESEARCH PROJECT: About 90% of people who develop cardiovascular disease have prior exposure to risk factors that could be targeted through lifestyle interventions. E-mail based walking programs that promote sustainable ecological supports for active lifestyles hold promise for cardiovascular disease risk-reduction, but few such programs have been developed or evaluated with objective outcomes. The purpose of this study is to conduct a randomized controlled trial to evaluate the effects of three walking programs: (1) Usual Care: walking information; (2) WalkLink: 12-week e-mail based walking program; and (3) WalkLink+: 12-week e-mail based walking program with ecological supports, among 220 sedentary adults with risk factors for cardiovascular disease recruited through primary care settings. Primary specific aims include: (1) To evaluate the effects of the three programs on change in aerobic fitness, blood pressure, body composition, body mass index, and moderate and vigorous walking and physical activity from baseline to posttest, and at 6-month follow-up; (2) To evaluate the effect of selected moderator/mediator variables on program outcomes, including: self-management skills (e.g., goal-setting, self-monitoring), social support (e.g., number of walking partners, social cues), and physical support (e.g., neighborhood walkability, physical cues). The proposed research builds upon an email-based walking program Dr. Rovniak previously conducted, and her current research in implementing ecological supports to promote AIDS prevention and tobacco control.   CANDIDATE AND ENVIRONMENT: Liza S. Rovniak received her Ph.D. in Clinical Health Psychology in 2003. Her long-term goal is to launch an independent research career with emphasis on designing economically sustainable lifestyle change interventions to promote physical activity and reduce risk of cardiovascular disease. To achieve this goal, Dr. Rovniak proposes to complement her psychology training with population based public health approaches important for developing sustainable interventions through: (1) training at Dr. Mel Novell's Center for Behavioral Epidemiology and Community Health; (2) training at Dr. James Sallis’Active Living Research Center; and (3) completing an MPH at San Diego State University.   RELEVANCE: Sustainable physical activity programs are urgently needed, as 70% of U.S. adults are inactive. Email-based walking programs could be widely disseminated to reduce risk of cardiovascular disease.  (End of Abstract)   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99HL088021-01       

 

Program Director:

MONDORO, TRACI

Principal Investigator:

SORROR, MOHAMED                     

MDOT (MB CHB)

Title:

Impact of Comorbidities on Outcomes of Allogeneic Transplantation

Institution:

FRED HUTCHINSON CANCER RESEARCH CENTER

SEATTLE, WA

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant):   Project Summary: Allogeneic hematopoietic cell transplantation (HCT) is a potentially curative therapy for various hematological diseases. However, many patients who could potentially benefit from HCT have been ineligible for the procedure due to comorbidities and age. With the development of reduced-intensity regimens and improvements in supportive care after myeloablative HCT, increasing numbers of elderly patients and those with comorbidities have been offered allogeneic HCT. Dr. Sorror, and a collaborator, Dr. R. Diaconescu, have published the first reports describing the importance of comorbidities in predicting HCT outcomes. Dr. Sorror went on to develop a new and more sensitive tool to assess comorbidities specific for recipients of allogeneic HCT. The HCT-specific-comorbidity index (HCT-CI) has created unique opportunities to better understand the impact of comorbidities on HCT outcomes and it forms the basis for this proposal. The proposal is focused on further evaluating and developing the prognostic value of comorbidities for outcomes in HCT recipients with the eventual aim of creating a universally applicable comorbidity index. During the Mentored Phase, the reliability and validity of the HCT-CI will be retrospectively tested among patients transplanted at multiple centers. In addition, scores weighting the impact of age intervals on HCT outcomes will be developed to form composite scores with the HCT-CI. Results of these studies will guide Dr. Sorror to proceed into the Independent Phase, which will address two parallel major aims. First, the biological impact of comorbidities on causes of death, particularly those associated with acute graft-versus-host disease and organ failures, and quality of life after HCT will be assessed comparing scores from the  HCT-CI to those from the comorbidity-aging composite index. This will involve both retrospective reviews of medical records of previously transplanted patients and analyses of prospective clinical trials to include larger number of patients and to ensure prospective reproducibility of the impacts of comorbidities. The second aim will prospectively investigate three different methods aimed at simplifying collection of comorbidity data and develop an educational program for evaluation of comorbidities by data registrars and, thereby, facilitate the more wide-spread incorporation of comorbidity assessment at HCT centers.   Relevance: The goal of the proposal is to improve pretransplant prognostic assessment of survival and quality of life in patients with malignant and non-malignant blood disorders who are treated with allogeneic HCT and eventually establish a universally applicable comorbidity index, which will facilitate comparing results of clinical trials conducted at different academic centers. (End of Abstract)   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99HL088048-01       

 

Program Director:

MONDORO, TRACI

Principal Investigator:

RODRIGUEZ-PORCEL, MARTIN                     

MD

Title:

Role of Oxidative Stress in Stem Cell Differentiation and Survival

Institution:

MAYO CLINIC COLL OF MEDICINE, ROCHESTER

ROCHESTER, MN

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant):   Stem cell transplantation offers much promise as a potential treatment for myocardial salvation at the end stages of coronary artery disease (CAD), and much interest has been placed in the differentiation capacity of different population of stem cells. However, little is known about the regulatory mechanisms of stem cell differentiation in vivo, and under hostile conditions, like myocardial infarction. Myocardial infarction leads to changes in the local microenvironment and increases oxidative stress, which can regulate cellular differentiation and survival. The long-term goal of our program is to study the biology of stem cells after transplantation to the heart. Our primary hypothesis in this proposal is that changes in oxidant status play a role in stem cell differentiation and survival in the mycoardium. To test that hypothesis we have the following specific aims: in Specific Aim 1 we will differentiate bone marrow stromal cells into cells with myocyte characteristics, both in cell culture and in living subjects, and we will use molecular techniques to track this differentiation non-invasively, something that could be done until recently. For that purpose we will use reporter imaging technology and optical imaging. In Specific Aim 2, we will examine if increased oxidative stress is involved in stem cell differentiation and survival. For that, will be induced in cell culture and in living subjects (after myocardial infarction), after which stem cell differentiation and survival will be tracked using molecular imaging techniques (optical imaging). In addition, we will study pathways related to oxidative stress (i.e. nitric oxide), and examine their role in stem cell differentiation. Lastly in Specific Aim 3, we will learn from Aims 1 and 2 and "genetically engineer" stem cells so they are better prepared to differentiate and survive in hostile condition, like the one found in states of myocardial ischemia and infarction.   The studies proposed in this grant will provide invaluable information on the role that the micro-environment plays in stem cell differentiation and survival and can lead to novel and improved therapeutic strategies. Stem cell therapy provides a great opportunity to re-constitute a damaged heart, but we first need to elucidate the mechanisms that regulate stem cell differentiation and survival. In this study we propose that specific biological pathways (i.e., oxidant status) can be involved in such response. Understanding these mechanisms that regulate stem cell survival will lead to better and improved therapies. (End of Abstract)     

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99HL088317-01       

 

Program Director:

VARGHESE, JAMIE

Principal Investigator:

ARJUN, DEB                     

 

Title:

Role of Sfrp2 in Cardiac Regeneration

Institution:

DUKE UNIVERSITY

DURHAM, NC

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant):   The static view of the heart as a terminally differentiated organ incapable of any regeneration has  undergone considerable change with the discovery of multipotent cardiac progenitor cells (CPCs)  residing within the heart. However despite their existence, it is apparent that the regenerative ability of  resident cardiac progenitors is not sufficient to regenerate myocardium and prevent ventricular  dysfunction after myocardial infarction. The signals regulating differentiation of resident CPCs are  currently unclear. The long-term goals of the project are to identify and understand factors that  determine myogenic differentiation of resident CPCs after myocardial injury. We show here that  secreted frizzled related protein 2 (Sfrp2), a Wnt modulator, inhibits cardiomyogenic differentiation of  P19CL6 cells, a murine embryonal cell line, well studied for mammalian myogenesis. We demonstrate that resident CPCs express Sfrp2 and cardiomyocytes increase Sfrp2 expression following hypoxic injury. We have thus hypothesized that Sfrp2 in an autocrine or paracrine fashion inhibits differentiation of resident CPCs. The specific aims include: 1) Determining the effects of Sfrp2 on myogenic differentiation of CPCs, 2) Determining whether alteration of Sfrp2 expression in CPCs or in the heart after myocardial injury affects myocardial regeneration, and 3) Determining whether Sfrp2 modulates canonical Wnt signaling in mediating its effects on differentiation of CPCs. We have isolated CPCs from the adult mouse heart and will initially determine the effects of Sfrp2 on myogenic differentiation of these cells in vitro. Subsequently, we will use RNA interference techniques to alter Sfrp2 expression on isolated CPCs as well as in the heart following injury to elucidate the role of Sfrp2 in regulating myogenesis in vivo. Finally, we will use molecular and biochemical assays to interrogate the effects of Sfrp2 on canonical Wnt signaling in CPCs. The candidate wishes to work on cardiac regeneration as a long term goal; this project thus serves as an ideal platform to transition to independence. Duke University Medical Center provides a rich collaborative and integrated environment for training of physician-scientists. Relevance: Owing to the limited regenerative capacity of the heart, heart disease often results in dreaded sequelae of congestive heart failure. This proposal aims to determine how stem cells within the heart can be coaxed to form new heart muscle and could lead to the design of novel regenerative therapies of heart disease. (End of Abstract)     

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99HL088514-01       

 

Program Director:

VARGHESE, JAMIE

Principal Investigator:

KONTARIDIS, MARIA IRENE                    

PHD

Title:

Molecular Pathogenesis of the Cardiomyogenic Defects in LEOPARD Syndrome

Institution:

BETH ISRAEL DEACONESS MEDICAL CENTER

BOSTON, MA

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant):   SUMMARY: Recently, mutations in the SH2 domain-containing protein tyrosine phosphatase Shp2, have been implicated in cardiac disease. Shp2 was identified as the gene mutated in approximately 50% of cases of Noonan Syndrome (NS) and all cases of LEOPARD Syndrome (LS). NS and LS share several clinical features, including congenital heart defects, and, as such, were viewed as overlap syndromes. However, LS is NOT a disease variant of NS; LS-associated mutations in Shp2 are catalytically inactive and behave as dominant negatives, whereas Shp2 mutations in NS are catalytically hyperactive. This proposes a model in which LS mutations are loss-of-function and NS mutations are gain-of-function. Moreover, most LS patients develop a hypertrophic cardiomyopathy (HCM), which is unique to LS; few NS patients with Shp2 mutations develop HCM. The central hypothesis, therefore, is that biochemical differences between these two syndromic disorders give rise to distinct cardiac defects. This proposal will define the mechanism(s) by which Shp2 LS mutants interfere with positive signaling events upstream and/or downstream of Ras in the Erk/MAPK pathway, will determine the signaling pathways that are aberrantly regulated by LS in the heart, will identify the developmental interval in which Shp2 is required during cardiogenesis, and will generate and functionally analyze a murine model of LS. CANDIDATE: Maria Kontaridis will receive advanced training in the field of cardiology and will further develop skills in molecular and developmental biology, biochemistry, and mouse genetics during the mentored phase of this award. Benjamin Neel, her sponsor, is an expert in Shp2 and mouse genetics. Her advisory panel (Drs. Jonathan Seidman, Jeffrey Saffitz, Lewis Cantley and James Chang), all experts in cardiac development/pathophysiology and/or signal transduction, will contribute substantially to her training and career development. Long-term, she plans to become an independent research scientist at an academic institution and to direct her own lab in cardiac development, with an emphasis on the signaling mechanisms (and mutations therein) that lead to congenital heart disease.   RELEVANCE: This work will further define the mechanisms by which genetic mutations lead to cardiac  disease. These findings will advance our knowledge of cardiac function and pathogenesis through better understanding of the fundamental signaling mechanisms that mediate these processes.  (End of Abstract)    

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99HL088528-01       

 

Program Director:

COMMARATO, MICHAEL

Principal Investigator:

TEMEL, RYAN E                    

PHD

Title:

Mechanisms For PPARdelta Agonist-Induced Elevation of HDL in Non-Human Primates

Institution:

WAKE FOREST UNIVERSITY HEALTH SCIENCES

WINSTON-SALEM, NC

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant):   Reduction of LDL-cholesterol through the use of statins has been shown to significantly decrease the rate of mortality and morbidity caused by coronary heart disease (CHD). Nevertheless, CHD remains the leading cause of death for men and women in the United States. One reason for the persistence of CHD may be the lack of therapies that increase HDL-cholesterol (HDL-C). It is well established that HDL-C concentration is a strong, independent, inversely related risk factor for CHD. Because of data indicating that a 1 mg/dl increase in HDL-C decreases CHD risk by 2-3%, many pharmaceutical companies are attempting to develop therapies that will effectively elevate HDL-C levels. One class of compounds that may have great therapeutic potential are PPAR-delta agonists, which in non-human primates can elevate HDL-C by 43-79% and apoA-l, the major apolipoprotein of HDL, by 43%. In this application, we propose to define the mechanisms by which PPAR-delta agonists induce HDL-C elevation in non-human primates. For the mentored research phase, we will determine whether PPAR-delta agonists increase HDL-C by: 1) altering HDL production or catabolism; 2) changing the activity of plasma lipases, lipid transfer proteins, and LCAT; 3) modulating the mRNA and protein expression of genes involved in HDL metabolism. For the independent research phase, we propose to determine whether PPAR-delta agonists elevate HDL-C in monkeys that have been treated with antisense oligonucleotides (ASOs) that suppress hepatic expression of PPAR-delta. We feel confident that these studies will provide insights for the development of more-potent PPAR-delta agonists or other therapies that effectively increase HDL-C, which in turn could prevent CHD in hundreds of thousands of people each year in the United States and around the world.   Scientific data indicates that increasing HDL cholesterol may decrease the risk of heart disease, the leading cause of death for men and women in the United States. We propose to determine the mechanisms by which a new class of drugs, known as PPAR delta agonists, increase HDL-cholesterol in monkeys. Because of the high degree of similarity between the bodies of humans and monkeys, we feel confident that these studies will provide insights for the development of therapies that could increase HDL and prevent the deaths of hundreds of thousands of people each year from heart disease. (End of Abstract)   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99HL088692-01       

 

Program Director:

SARKAR, RITA

Principal Investigator:

BRUNETTI-PIERRI, NICOLA                     

MD

Title:

HDAd-mediated gene therapy for hemophilia B

Institution:

BAYLOR COLLEGE OF MEDICINE

HOUSTON, TX

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant):  HDAd are attractive gene therapy vectors that can mediate long-term, high level FIX expression from transduced hepatocytes leading to sustained phenotypic correction of FIX-deficiency in mice and dogs with no chronic toxicity. However, systemic high dose administration, required for efficient hepatic transduction, results in activation of an acute inflammatory response with potentially severe and lethal consequences. The mechanism responsible for Ad-mediated activation of the acute inflammatory response is not known, however, it is clearly dose-dependent. We have developed an in vivo gene therapy delivery approach for HDAd which has proven to be very successful in a large animal model. This method entails the use of balloon occlusion catheters to deliver HDAd preferentially to the liver of nonhuman primates. During the mentored phase, I propose to complete the nonhuman primate studies already initiated to establish dose-response relationship and vector biodistribution following vector delivery with this novel method. In Specific Aim 1, I will investigate the dose-response relationship ranging from 1x1010 to 1x1011 vp/kg of HDAd expressing baboon (-fetoprotein (bAFP) under the control of a liver specific promoter. In Specific Aim 2, I will investigate the biodistribution of HDAd vector delivered through balloon catheter-assisted delivery in nonhuman primates and to carry out formal toxicity studies, both performed under conditions to satisfy the requirements of the FDA for a phase I clinical trial.  In the independent phase, I propose to investigate safety and efficacy of the balloon catheter-assisted delivery of HDAd into the clinically relevant animal model of hemophilia B. The proposed experiments are designed to generate the data necessary to progress towards human clinical trials for the treatment of hemophilia B (Specific Aim 3). In Specific Aim 4, I will investigate HDAd expressing genetically engineered FIX molecules with greater catalytic activity. This strategy is specifically designed to achieve therapeutic FIX levels using low vector doses. If superior, these catalytically enhanced FIX molecules will not only increase the safety and efficacy of HDAd-mediated hemophilia B gene therapy, but will also be valuable for other vector systems as well as for recombinant protein replacement therapy. During the independent phase I also propose to investigate, in nonhuman primates, the efficacy and safety of liver-directed gene therapy using naked plasmid DNA vector (pDNA) delivered through the balloon catheter-assisted delivery (Specific Aim 5).  

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99MD002271-01       

 

Program Director:

HUNTER, DELORIS

Principal Investigator:

CARSWELL, STEVEN BERNARD                    

PHD

Title:

Risk Factors for HIV Among Urban African American Youth

Institution:

FRIENDS RESEARCH INSTITUTE, INC.

BALTIMORE, MD

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant): The candidate is a sociologist, and a former recipient of a Minority Investigator Award from NIDA, with knowledge and experience regarding community and environmental factors and their relationship to youth involvement in health-compromising behaviors in urban areas. The Social Research Center (SRC), where the candidate is currently employed as a research scientist, is the research campus of Friends Research Institute (FRI), a private non-profit institution established in 1955. The Center promotes pre-doctoral training experiences designed to facilitate careers in behavioral, public health, and public policy research, providing entry-level positions for talented graduate and undergraduate students in the behavioral sciences. The candidate's long-term career objective is to become an independent investigator. He would like to focus his professional career on developing and testing intervention models that place urban African American youth and adults at-risk for HIV/AIDS. The candidate proposes to be mentored by his primary sponsor Dr. Jeannette Johnson, a Native American, cross-cultural psychologist, who has extensive prevention research knowledge and expertise regarding individual, social, and cultural risk and protective factors associated with HIV/AIDS in minority communities. During the mentored phase, he also proposes to take courses regarding HIV/AIDS at the Bloomberg School of Public Health at John's Hopkins University and attend NIH and other HIV/AIDS related conferences. The primary aim of the proposed three-year cross-sectional study is to examine the extent to which specific risk and protective factors predict both perceptions of HIV risk and participation in risky sexual behavior among high-risk African American youth. These youth, currently attending Baltimore City Alternative Learning Centers (BCALC), have been expelled from traditional public schools for committing violent acts or for engaging in other serious infractions, with many engaging in risky sexual behavior. Half of the participants will be assessed the first project year and the remainder assessed in the second year. Participants will be 200 male and female students, between the ages of 11 and 17 randomly selected from two BCALC school sites. Assessment data will be collected from January through May during each of the two data collection years. The research study proposed has the potential to provide a greater understanding of issues related to perceptions of HIV risk and participation in risky sexual behaviors among high-risk urban African American youth. Findings from the study will be of significance to the field of public health by filling important knowledge gaps in terms of risk for HIV infection among such youth.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99MH080599-01       

 

Program Director:

DESMOND, NANCY L

Principal Investigator:

YE, BING                     

PHD  NEUROSCIENCE

Title:

Mechanisms Differentiating Dendrite Development form Axon Development

Institution:

UNIVERSITY OF CALIFORNIA SAN FRANCISCO

SAN FRANCISCO, CA

Project Period:

2006/09/25-2008/08/31

 

 

 

  DESCRIPTION (provided by applicant):   My career goal is to understand the mechanisms of neuronal compartmentalization and how this process contributes to nervous system function and to the pathogenesis of neurological disorders. I will pursue this goal by working in an academic institution as an independent investigator. During my postdoctoral training in the laboratory of Dr. Yuh Nung Jan at UCSF, I have been using Drosophila PNS neurons as a model system to study the mechanisms that differentiate the development of dendrite from axon, two major compartments of a neuron. This training complements my doctoral training in vertebrate neurobiology. I plan to combine the strength of Drosophila (in vivo and superb genetics) and cultured rat hippocampal neurons (well- characterized cell biology) to study neuronal compartmentalization. The objective of this research is to examine the roles of the secretory pathway in differentiating dendrite and axon development. From a genetic screen in Drosophila, we isolated several mutants (dar mutants) with reduced dendritic arbors but normal axons. Dar2, 3, and 6 regulate the secretory pathway, suggesting that this pathway differentiates dendritic and axonal growth. I propose two aims. First, I will determine cell biological mechanisms through which the secretory pathway differentially controls dendritic and axonal growth. New techniques will be developed to complement existing ones to identify such mechanisms. Membrane traffic through the secretory pathway will be monitored in live wild-type and mutant Drosophila embryos/larvae and cultured hippocampal neurons. Second, I will identify and characterize genes that control the differential development of dendrites and axons by regulating key players of the secretory pathway. Dar7 (genetically interacts with dar2 and 3), darl (genetic interaction untested), and Trailer Hitch (regulates the secretory pathway) will be studied. Their mammalian homologs will be examined in cultured neurons to determine if the mechanisms are conserved in mammals. This research will provide much-needed information for understanding the causes of neurological disorders characterized by preferential damage to dendrites (e.g., Rett's syndrome) or by defective Golgi function (e.g., amyotrophic lateral sclerosis). Such information will also allow the design of therapeutic approaches.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99NS057906-01       

 

Program Director:

MAMOUNAS, LAURA

Principal Investigator:

CUI, BIANXIAO                     

 

Title:

Imaging nerve growth factor signal transduction in live neurons

Institution:

STANFORD UNIVERSITY

STANFORD, CA

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant):   Our broad objective is to understand the mechanisms by which the nerve growth factor (NGF) signal is propagated from the axon terminal to the cell body. NGF retrograde signaling is critical for the survival, differentiation, and maintenance of certain types neurons. Disrupted NGF retrograde transport was reported to contribute to the loss of the basal forebrain cholinergic (BFC) neurons in the brains of patients with Alzheimer's Disease or Down's Syndrome. This project will use advanced imaging techniques to directly visualize NGF transport in live neurons in real time. We focus on exploring dynamic features of NGF transport in normal and Down's Syndrome mice. The aims are: 1. Characterize the movement of NGF-containing endosomes in axons and define their pausing mechanism(s), by using quantum dot conjugated NGF to track endosomal movements with nanometer resolution. 2. Determine whether NGF-lacking endosomes are present, whether they are relevant for NGF signaling, and whether there are alternative signaling pathways independent of endosomal transport, by marking the NGF-lacking endosomes with photo-activatable green fluorescence proteins that are fused to the C-terminal of TrkA receptor. 3. Identify the abnormal features of disrupted NGF transport in Down Syndrome mouse neurons, by characterizing individual features of transport dynamics, which include the average speed, the moving speed, the pausing duration, and the pausing frequency. 4. Determine how amyloid precursor protein overexpression leads to the abnormal NGF retrograde transport in Down Syndrome mouse by examining how overexpression of amyloid precursor protein in DS mice might cause defective structural or axonal features that lead to disrupted NGF transport. Achieving those aims will increase our understanding of how NGF signal is propagated in normal and degenerative neurons. More broadly, those studies will contribute to elucidate the pathogenesis of Alzheimer's disease and Down syndrome.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99NS057931-01       

 

Program Director:

TALLEY, EDMUND M

Principal Investigator:

COLON-RAMOS, DANIEL A                    

PHD

Title:

Synaptic target selection in the thermotaxis neural circuit of C. elegans

Institution:

STANFORD UNIVERSITY

STANFORD, CA

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant):   The human brain consists of approximately 100 billion neurons, which form over 100 trillion synapses with specific targets. How neurons find the correct targets and how the correct wiring of the brain influences behavior are central questions, and the focus of this proposal. The nematode C. elegans offers an excellent model system to explore how synaptic specificity is achieved in vivo, and how correct synaptic choices influence the formation of neuronal circuits, and behavior. AIY, an important interneuron in the C. elegans brain, receives inputs from multiple sensory neurons to modulate behaviors such as thermotaxis, chemotaxis and learning. During development AIY contacts many neurites, but selects only three neurons (RIA, RIB and AIZ) as its postsynaptic partners. The molecular mechanisms used by AIY to discriminate between potential targets and form functional neuronal circuits are not understood. Here I propose to characterize how synaptogenesis is regulated in the complex environment of the C. elegans brain by studying synaptic formation in the thermotaxis neural circuit. A visual forward genetic screen on AIY synapses has yielded multiple mutants with abnormal synaptic patterns. I will identify AIY synaptic specificity molecules by characterizing these mutants. Initial characterization of one class of mutants indicates that immunoglobulin superfamily protein UNC-40/DCC directs AIY synaptogenesis in a cell autonomous manner. In unc-40 mutant, AIY exhibits normal axon trajectory with abnormal presynaptic locations. UNC-40 localizes to AIY presynaptic sites in wild type animals. Furthermore, mislocalization of UNC-40 leads to ectopic presynaptic terminal formation at the location of mislocalized UNC-40. Further experiments will identify the mechanism by which unc-40 directs synaptic target selection in AIY. Future characterization of mutants with similar AIY phenotype as unc-40 will determine the molecular signaling pathway that leads to correct AIY synaptogenesis. Together our work promises to lend us insights into the molecular components that direct correct synaptogenesis in the C. elegans brain. Altered synaptogenesis might lead to a number of neurodevelopmental disorders and human diseases such as schizophrenia and autism. Understanding correct synaptogenesis should provide insights into how functional neuronal circuits are constructed during development and how the correct formation of these circuits affects behavior.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99NS057934-01       

 

Program Director:

GWINN-HARDY, KATRINA

Principal Investigator:

ROLL-MECAK, ANTONINA                     

PHD

Title:

Elucidation of the Biochemical Mechanism and In Vivo Functions of Spastin

Institution:

UNIVERSITY OF CALIFORNIA SAN FRANCISCO

SAN FRANCISCO, CA

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant):   The objective of this award is to complete my training and to establish a highly interdisciplinary lab at an academic institution in the U.S., focused on the study of the mechanism of cytoskeletal regulators. My lab will take a comprehensive, multifaceted approach by linking atomic resolution structural information with single molecule dynamics in vitro and in the larger context of the cell. The research focus of this award is to dissect the biochemical and cellular mechanisms of spastin. Mutations in the spastin gene are the leading cause of hereditary spastic paraplegias, a group of poorly understood neurodegenerative disorders characterized by axonopathy. I have discovered that spastin severs microtubules (Roll-Mecak and Vale, 2005). Disease mutations impair severing, linking spastin's remodeling of the microtubule cytoskeleton to neurodegeneration. The research plan outlined here is highly interdisciplinary, integrating techniques and concepts from structural biology, biophysics and cell biology to answer three fundamental questions about spastin function: 1) What is spastin's atomic structure throughout its ATPase cycle and how does it bind and break the microtubule; 2) How does it use the energy of ATP hydrolysis to disassemble the microtubule; and 3) How does spastin affect microtubule architecture and dynamics in the living cell and what are the cellular consequences incurred when spastin is depleted or mutated ? Despite its importance for neuronal survival very little is known about spastin. A detailed understanding of its mechanism and basic cell biology are critical to understanding the causes of the disease and this proposal sets the fundamental mechanistic groundwork that is needed to develop therapies further down the road. Perturbation of microtubule dynamics and architecture has emerged as a common theme in a variety of neurodegenerative diseases and an understanding of spastin's effects will have implications for the etiologies of all these disorders. Lay Summary: The goal of this research is to understand the function of an enzyme, spastin, that is defective in the majority of patients with hereditary spastic paraplegias, a group of poorly understood neurodegenerative disorders. I discovered that spastin breaks a central component of the cell's skeleton. This research will provide the basic groundwork needed for the development of treatments for this group of disorders and also increase our understanding of other neurodegenerative disorders.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99NS058111-01       

 

Program Director:

MURPHY, DIANE

Principal Investigator:

WEST, ANDREW B                     

PHD

Title:

The Role of LRRK2 in the Pathogenesis of Parkinson's Disease

Institution:

JOHNS HOPKINS UNIVERSITY

BALTIMORE, MD

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant):   Parkinson's disease (PD) is a common progressive neurodegenerative disorder. Current therapeutic approaches initially alleviate symptoms but eventually cause deleterious side effects and fail to halt disease progression. A significant genetic component to disease was recently identified as mutations in the leucine- rich repeat kinase 2 gene (LRRK2). LRRK2 mutations cause a highly-penetrant dominant disease phenotype indistinguishable from typical PD. Preliminary data suggest that LRRK2 mutations perturb the normal enzymatic activity of LRRK2 by increasing kinase activity. Such increases in kinase activity are associated with neurotoxicity. The mentored phase of this proposal dissects LRRK2 toxicity using a combination of approaches including inducible gene expression, RNA interference, and viral-delivery of mutant LRRK to primary neurons. The goal is to define LRRK2-mediated kinase dependent cell death cascades. Complementary to understanding the role of LRRK2 in health and disease will be the identification of LRRK2 kinase substrates in relevant cells. As the first of two independent phase projects, LRRK2 kinase substrates will be identified using a combination of novel technologies to assess the complete set of LRRK2 interacting proteins in an unbiased manner. The functional impact of LRRK2 mediated kinase activity on protein substrates will be evaluated, particularly in existing and emerging models of PD. Finally, the second independent phase aim utilizes the tools and techniques developed in this proposal to perform high-throughput screening to identify small-molecule LRRK2 kinase inhibitors. Small molecule inhibitors will be used to definitively assess the role of LRRK2 kinase activity in causing neurotoxicity. LRRK2 may represent a far upstream element in the pathogenesis of PD. Through the understanding of LRRK2, other genes involved in PD may fall into a common biochemical pathway where disease intervention is possible. Mutations in the leucine-rich repeat kinase 2 (LRRK2) gene are a common cause of Parkinson's disease. This proposal explores the role of LRRK2 in neurodegeneration with a focus on identifying pathways and drugs to intervene in the disease process.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99RR024110-01       

 

Program Director:

CHANG, MICHAEL

Principal Investigator:

BHALLA, NEEDHI                     

PHD

Title:

Characterization of the Synapis Checkpoint in C. elegans Meiosis

Institution:

UNIVERSITY OF CALIFORNIA BERKELEY

BERKELEY, CA

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant): Meiosis generates haploid gametes from a diploid cell such that a diploid genome is restored upon fertilization. The proper segregation of chromosomes during the meiotic divisions depends on events in meiotic prophase, such as the pairing and synapsis of homologous chromosomes and crossover recombination. Errors in chromosome segregation are usually fatal to the fertilized zygote but can also result in cancer predisposition or serious developmental disorders. I have identified a meiotic checkpoint that responds to defects in homolog synapsis, independent of a DNA damage/recombination checkpoint, and activates apoptosis to avoid the generation of aneuploid gametes. Not all unsynapsed sequences have the capacity to trigger this checkpoint; rather, this pathway is specifically activated by unsynapsed pairing centers (PCs), chromosome sites that promote synapsis in C. elegans. Furthermore, the checkpoint requires the C. elegans homolog of PCH-2, a budding yeast pachytene checkpoint gene, suggesting that the molecular mechanism that detects synaptic failure is widely conserved.   I plan to further characterize this synapsis checkpoint. I am particularly interested in the PC's contribution to synapsis checkpoint activation. The identification and characterization of proteins that interact with factors required for PC function will provide insight into how this locus activates the checkpoint when unsynapsed. Studies that address the regulation of heterochromatin on unsynapsed chromosomes and how the PC may inhibit the DNA damage checkpoint will also be undertaken. I will determine the role of the synaptonemal complex (SC) in the synapsis checkpoint by characterizing two genes that interact with the SC and appear to be required for the checkpoint by preliminary RNA inteferference (RNAi) experiments. I will investigate the function and regulation of the known checkpoint component, pch-2; a GFP-PCH-2 fusion protein will be localized in a variety of genetic backgrounds and a reagent will be provided to identify interacting proteins biochemically. Furthermore, I will identify additional components of the checkpoint by undertaking an RNAi screen that will focus on candidate genes that fulfill specific expression and phenotypic profile criteria. These complementary approaches will enable me to gain a molecular and mechanistic understanding of how homolog synapsis is monitored and how an unsynapsed or inappropriately synapsed homolog generates a checkpoint signal that is ultimately translated into an apoptotic response.   Meiosis produces gametes, such as eggs and sperm. Checkpoints monitor meiotic events to ensure that gametes have the correct number of chromosomes. If a gamete has an incorrect number of chromosomes, the embryo that results from fertilization is often inviable. Occasionally, an embryo inherits an extra chromosome that is not lethal but can cause cancer predisposition or serious developmental defects.   

 

 

 

 

Date Run:  11/30/06                                                              PUBLIC ABSTRACTS                                                              

 

Grant:

1K99RR024119-01       

 

Program Director:

CHANG, MICHAEL

Principal Investigator:

LIN, FANG                      

PHD  PHARMACOLOGY & PHYSIOLOGY

Title:

G-protein Signaling in Zebrafish Primordial Germ Cell Migration

Institution:

VANDERBILT UNIVERSITY

NASHVILLE, TN

Project Period:

2006/12/01-2008/11/30

 

 

 

  DESCRIPTION (provided by applicant): Diverse cell movements during animal development contribute significantly to the establishment and maintenance of normal body plan and organogenesis. G protein signaling is one of many molecular genetic mechanisms that control these processes. Previously I showed that Ga12/13 is required for distinct cell behaviors that drive zebrafish gastrulation. In the mentored phase, I will work under supervision of Drs. Lila Solnica-Krezel and Heidi Hamm to continue characterizing the cell behaviors mediated by Ga12/13 signaling to identify the downstream and upstream regulators of Ga12/13 during gastrulation. These studies will provide new insights into the molecular mechanism by which Ga12/13 modulate cell movements during embryogenesis. Knowledge and crucial techniques obtained during this period will provide me a solid foundation to launch my own independent research as proposed below.   I have recently discovered that G protein signaling is also involved in migration of the progenitors of the gametes, primordial germ cells (PGCs). As in many other organisms, PGCs in zebrafish migrate from the position where they are specified toward the region where the gonad develops. It has been shown that this migration is governed by a chemokine G protein-coupled receptor, CXCR4b, and its ligand, SDF1a. However, whether signaling proceeds through Ga? or Ga subunits, and their downstream effectors that are involved in PGC migration remain largely unknown. My preliminary results indicated that Ga?, Ga12/13 and probably Gaq are involved in the PGC movements. I hypothesize that PGC migration in zebrafish is mediated by diverse G protein signaling pathways probably through multiple receptors. I will employ a combination of genetic, cellular, pharmacological and biochemical approaches to test this hypothesis.   In aim 1, I will characterize Ga? function in PGC migration, and test my hypothesis that Ga? transmit the SDF1a/CXCR4 signal. I will also identify the downstream effectors of Ga? that are required for PGC migration. In aim 2, I will determine the roles of Ga subunits during PGC migration and investigate the involvement of cell adhesion and RhoA in this process. Based on my findings that multiple G proteins may be involved in PGC migration, my aim 3 is to identify G protein coupled receptors other than Cxcr4b that regulate PGC migration, which may uncover unknown signaling pathways that control PGC migration.   Given that the signaling pathways of cell migration are conserved during embryogenesis, immune response, and cancer cell metastasis, our study using an in vivo model with a vertebrate body plan will provide new insights into cell movement behaviors in normal development and disease.