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Published on: January 11, 2011
Molecular diversity of voltage-dependent Ca2+ channels
R W Tsien1, P T Ellinor, W A Horne
1Department of Molecular and Cellular Physiology, Beckman Center, Stanford University Medical Center, CA 94305.
Abstract:
Voltage-dependent Ca2+ channels regulate Ca2+ entry and thereby contribute to Ca2+ signalling in many cells. Functional studies have uncovered several types of Ca2+ channel, distinguished by pharmacology, electrophysiology and tissue localization. More recently, molecular cloning has revealed an even greater diversity among Ca2+ channels, arising from multiple genes and alternative splicing. L-type, dihydropyridine-sensitive Ca2+ channels have been the most extensively characterized to date. Recently, Numa's group has reported the cloning and expression of a dihydropyridine-insensitive Ca2+ channel from brain that most closely resembles the P-type channel described by Llinas and colleagues. These results contribute to rapidly growing knowledge about molecular determinants of Ca2+ channel diversity.
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