Our
NIH and NSF-funded research programs focus on how environmental and genetic processes influence metazoan development and celluar processes. We are particularly interested in identifying the molecular mechanisms involved with oxygen deprivation responses and suspended animation in C.
elegans, characterizing embryonic diapause in killifish, and the interaction between stress responses and aging.
SUSPENDED ANIMATION AND OXYGEN DEPRIVATION
The nematode C. elegans responds to low levels of oxygen (anoxia) by entering into a state of suspended animation in which developmental and cell cycle progression arrests. Of particular interest to us is understanding how cell cycle progression arrests in embryos in a state of suspended animation. Furthermore, behavioral processes such as eating and movement, as well as reproductive processes including egglaying and ovulation reversibly arrests in animals in a state of suspended animation. We have discovered several genes that are required for anoxia-induced suspended animation and are working on the genetic pathways and physiological states that extend the capacity of nematodes to survive suspended animation.
C. elegans respond to hypoxia by slowing developmental progression and altering behavior. We are interested in characterizing the cellular, genetic and behavial responses to chronic hypoxia. The hypoxia inducing factor (HIF-1) is central to the response metazoans have to oxygen deprivation. However, we are using genetics to identify HIF-1 independent hypoxia responses. View C. elegans images.
Oxygen deprivation is central to many human health related issues including pulmonary dysfunction, myocardial infarction, blood loss, stroke, and solid tumor resistance to therapies. Thus, the genetic, physiological and cellular approaches we use to better understand oxygen deprivation and suspended animation can contribute to a greater understanding of many disease processes.
DIAPAUSE
In a natural environment many organisms enter into a metabolic arrest in response to environmental changes or stress. Fascinating examples of metabolic/developmental arrests include torpor, diapuase and hibernation. We are using the killifish embryo as a model to better characterize embryonic diapause at a cellular and genetic level. A comparison between anoxia induced suspended animation and embryonic diapuse will allow us to identify conserved and unique processes for each state. View killifish and their natural habitat (Maine).
AGING AND STRESS
Many labs have uncovered genetic processes involved with aging. We are interested in further understanding the relationship between stress responses and longevity. Interestingly, several of the genetic pathways or physiological changes involved with longevity (insulin-signaling or reproduction) also have a role in stress responses. We are using genetic and physiological techniques to further understand overlaping and distinct genetic pathways between aging and stress. Furthermore, we would like to determine, at a molecular level, how stress influences the aging processes.
For more details on these projects.
