Electrical activity of nerve cells is determined by ion channels found within the cell membrane. The electrical excitability of individual nerve cells depends upon the types of ion channels expressed, the relative and absolute densities, and the spatial distributions of ion channels in different regions of the cell. These factors have a functional significance and any modification to these factors could be a cause of neuronal plasticity. The molluscan nervous system provides an important model for the study of neural circuits and neuronal plasticity. This research project will investigate the mechanisms molluscan neurons use to process information in the nervous system. Electrophysiological methods of voltage and patch clamping will be utilized to study the biophysics of membrane ion channels and to map the spatial distribution of ion channels in different areas of the cell. Biophysical properties that are modulated by activity, such as the inactivation gating of calcium and potassium, will be examined to help encode the time history of neuronal activity. Video fluorescence microscopy will be used to study the spatial patterning of intracellular calcium signals and the nature of the cytoskeleton. Results of this study will contribute to the understanding of neuronal information processing and the specializations responsible for the functional individuality of neurons.
