Referenced in: none

Automatically associated channels: Cav2.1 , Cav2.2

Title: Tetraspanin-13 modulates voltage-gated CaV2.2 Ca2+ channels.

Authors: Robert T Mallmann, Thomas Wilmes, Lucia Lichvárová, Anja Bührer, Barbara Lohmüller, Jan Castonguay, Lubica Lacinova, Norbert Klugbauer

Journal, date & volume: Sci Rep, 2013 , 3, 1777

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/23648579

Abstract
Integration of voltage-gated Ca(2+) channels in a network of protein-interactions is a crucial requirement for proper regulation of channel activity. In this study, we took advantage of the specific properties of the yeast split-ubiquitin system to search for and characterize so far unknown interaction partners of CaV2 Ca(2+) channels. We identified tetraspanin-13 (TSPAN-13) as an interaction partner of the α1 subunit of N-type CaV2.2, but not of P/Q-type CaV2.1 or L- and T-type Ca(2+) channels. Interaction could be located between domain IV of CaV2.2 and transmembrane segments S1 and S2 of TSPAN-13. Electrophysiological analysis revealed that TSPAN-13 specifically modulates the efficiency of coupling between voltage sensor activation and pore opening of the channel and accelerates the voltage-dependent activation and inactivation of the Ba(2+) current through CaV2.2. These data indicate that TSPAN-13 might regulate CaV2.2 Ca(2+) channel activity in defined synaptic membrane compartments and thereby influences transmitter release.