The overall goal of this research is to understand the function of calcium channels. Previous results have indicated that the selectivity of the channel for calcium is dependent upon both channel diameter and a high affinity, calcium binding site within the channel. These results formed the basis for a theoretical model which quantitatively describes the essential features of calcium channel selectivity of the vertebrate skeletal muscle calcium channel. Current studies are directed toward understanding the phenomenon of calcium-induced inactivation of the calcium channel and toward comparing the voltage gating of calcium channels in skeletal and cardiac muscle. Experiments are also planned to study the turnover of calcium channels in neuronal membranes using as a probe the channel binding protein, omega conotoxin. Controlled entry of calcium into cells by way of calcium channels is a critical factor in control of skeletal muscle contraction and heart beat, in communication between nerve cells, and in release of many hormones. The results of this research will enhance our understanding of this important process.
