Cav1.1: The atypical prototypical voltage-gated Ca2+ channel

Ca(v)1.1 is the prototype for the other nine known Ca-v channel isoforms, yet it has functional properties that make it truly atypical of this group. Specifically, Ca(v)1.1 is expressed solely in skeletal muscle where it serves multiple purposes; it is the voltage sensor for excitation-contraction coupling and it is an L-type Ca2+ channel which contributes to a form of activity-dependent Ca2+ entry that has been termed Excitation-coupled Ca2+ entry. The ability of Ca(v)1.1 to serve as voltage-sensor for excitation-contraction coupling appears to be unique among Ca-v channels, whereas the physiological role of its more conventional function as a Ca2+ channel has been a matter of uncertainty for nearly 50 years. In this chapter, we discuss how Ca(v)1.1 supports excitation-contraction coupling, the possible relevance of Ca2+ entry through Ca(v)1.1 and how alterations of Ca(v)1.1 function can have pathophysiological consequences. This article is part of a Special Issue entitled: Calcium channels. (c) 2012 Elsevier B.V. All rights reserved.