Title:Voltage-Gated Ca<sub>v</sub>1 Channels in Disorders of Vision and Hearing
VOLUME: 8 ISSUE: 2
Author(s):Mei-ling A. Joiner and Amy Lee
Affiliation:Department of Molecular Physiology and Biophysics, University of Iowa, PBDB 5318, 169 Newton Rd., Iowa City, IA 52242, USA.
Keywords:Cav1 channels, Cabeta, alpha2delta, calmodulin, CaBPs, harmonin, inner hair cell, photoreceptor, Rab3-interacting
molecule 2, ribbon synapse, thyroid hormone.
Abstract:Cav1 channels mediate L-type Ca2+ currents that trigger the exocytotic release of glutamate
from the specialized “ribbon” synapse of retinal photoreceptors (PRs) and cochlear inner hair cells
(IHCs). Genetic evidence from animal models and humans support a role for Cav1.3 and Cav1.4 as the
primary Cav channels in IHCs and PRs, respectively. Because of the unique features of transmission at
ribbon synapses, Cav1.3 and Cav1.4 exhibit unusual properties that are well-suited for their physiological
roles. These properties may be intrinsic to the channel subunit(s) and/or may be conferred by regulatory
interactions with synaptic signaling molecules. This review will cover advances in our understanding of the function of Cav1
channels at sensory ribbon synapses, and how dysregulation of these channels leads to disorders of vision and hearing.
