Modulation of TRPV4 gating by intra- and extracellular Ca2+ |
| |
Authors: | Watanabe Hiroyuki Vriens Joris Janssens Annelies Wondergem Robert Droogmans Guy Nilius Bernd |
| |
Institution: | Department of Physiology, Laboratorium voor Fysiologie, Campus Gasthuisberg, KU Leuven, Herestraat 49, B-3000 Leuven, Belgium. |
| |
Abstract: | We have studied the modulation of gating properties of the Ca2+-permeable, cation channel TRPV4 transiently expressed in HEK293 cells. The phorbol ester 4alphaPDD transiently activated a current through TRPV4 in the presence of extracellular Ca2+. Increasing the concentration of extracellular Ca2+ (Ca2+](e)) reduced the current amplitude and accelerated its decay. This decay was dramatically delayed in the absence of Ca2+](e). It was also much slower in the presence of Ca2+](e) in a mutant channel, obtained by a point mutation in the 6th transmembrane domain, F707A. Mutant channels, containing a single mutation in the C-terminus of TRPV4 (E797), were constitutively open. In conclusion, gating of the 4alphaPDD-activated TRPV4 channel depends on both extra- and intracellular Ca2+, and is modulated by mutations of single amino acid residues in the 6th transmembrane domain and the C-terminus of the TRPV4 protein. |
| |
Keywords: | |
本文献已被 ScienceDirect PubMed 等数据库收录! |
|