BioCurrents Research Center

BioCurrents Research Center

Marine Biological Laboratory 7 MBL Street Woods Hole, MA 02543-1015 www.mbl.edu/BioCurrents www.pharmabase.org	Principal Investigator and Contact Peter J. S. Smith, Ph.D. 508-289-7241; Fax: 508-540-6902
Grant No. P41 RR001395

Research Emphasis

This center offers a suite of advanced technologies designed to follow the dynamic properties of living cells, particularly as these relate to molecular transport and pathophysiology. Developed in-house are several electrochemical noninvasive microelectrode applications (<10µm tip diameters) relying on drift and noise reduction by using a modulation technique, termed self-referencing. Using differential signal analysis, the center offers techniques that can measure chemical gradients surrounding single cells and tissues. Applications using potentiometry, voltammetry, and amperometry are available for the detection of ions (e.g., potassium, hydrogen, and calcium) as well as electrically active molecules (e.g., oxygen, nitric oxide, and hydrogen peroxide). Enzyme-assisted electrodes for the detection of molecules such as glucose and glutamate are also available.

Current Research

Instrument development includes improvement of the existing electrochemical systems, all targeted to operate at the level of a single cell. Additionally, the center is working on inclusion of more complex electrochemical detection techniques, fusion of sensor modalities in electro-optical systems, faster signal processing techniques, transporter expression and biophysical analysis in expression systems and bilayers, and probe development for air-exposed surfaces.

The center also supports most conventional electrophysiologic techniques working in conjunction with electrochemical detection, confocal microscopy, and other detection methods. Biological studies focus on the role of molecular transport in cell physiology and development with an emphasis on characterizing transport mechanisms and their role in basic biology and disease. Diseases of metabolism, the nervous system, and reproductive health have been a particular focus.

Research Capabilities

Instruments

Resource staff design and manufacture amplifiers, microstepper motion controllers, and manipulators. There are nine experimental platforms, of which eight have compound microscopes: seven are inverted and one is upright (Zeiss AxioScope). One Axiovert is equipped with a Perkin Elmer Spinning Disc confocal. A second Axiovert is equipped with an in-house design for low-light and luminescent imaging. Adenovirus for luciferase and green fluorescent protein are available. All platforms can be temperature-controlled. More than one detection system can be operated at a time. Culture facilities are available for both mammalian and non-mammalian systems.

Software

Operating software: All experimental platforms run on personal computers. The data collection and motion-controlling program (IonView written and maintained in-house) runs on Windows. All computers are linked to a local area network and the outside via the Marine Biological Laboratory (MBL) server.

Informatics: As a service to the community, the center maintains a database of compounds targeting diverse aspects of cellular dynamics, from transporters to metabolism.

Special Features

Because the MBL hosts numerous students and visiting investigators throughout the year, abundant accommodations are available on and off campus, including single dorm style rooms and cottages more suitable for families.

Available Resources

Visiting investigators have access to the extensive facilities of the MBL. This includes advanced imaging techniques such as multiphoton microscopy (Zeiss 510—both upright and inverted). Animal care facilities are available for mammalian and aquatic organisms.

Training Opportunities and Workshops

The resource is open throughout the year for training as well as research visits. Training includes operation of the specialized technologies developed as well as in electrode manufacture and imaging. Through the MBL Fellowship program, visitors to the center can compete for independent funding to support a research visit. Meetings are planned biannually to take place at major scientific venues. The focus will be on the biological problems relating to center activities.

Publications

1. Twig, G., Graf, S. A., Messerli, M. A., Smith, P. J. S., Yoo, S. H., and Shirihai, O. S., Synergistic amplification of beta-amyloid and interferon-gamma-?induced microglial neurotoxic response by the senile plaque component chromogranin A. American Journal of Physiology 288:C169–C175, 2005.

2. Beaulieu, V., Da Silva, N., Pastor-Soler, N., Brown, C. R., Smith, P. J. S., et al., Modulation of the actin cytoskeleton via gelsolin regulates vacuolar H+ATPase (V-ATPase) recycling. Journal of Biological Chemistry 280:8452–8463, 2005.

3. Li, R., Chase, M., Jung, S.-K., Smith, P. J. S., and Loeken, M. R., Hypoxic stress in diabetic pregnancy contributes to defective embryo gene expression and defective development by inducing oxidative stress. American Journal of Physiology 289:E591–E599, 2005.

4. Pethig, R., Jakubek, L., Sanger, R. H., Heart, E., Corson, E., and Smith, P. J. S., Electrokinetic measurements of membrane capacitance and conductance for pancreatic b-cells. IEE Proceeding of Nanobiotechnology 152:189–193, 2005.