Referenced in: none

Automatically associated channels: TRP , TRPM , TRPML , TRPML3 , TRPV , TRPV5 , TRPV6

Title: A novel ion channel formed by interaction of TRPML3 with TRPV5.

Authors: Zhaohua Guo, Christian Grimm, Lars Becker, Anthony J Ricci, Stefan Heller

Journal, date & volume: PLoS ONE, 2013 , 8, e58174

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/23469151

Abstract
TRPML3 and TRPV5 are members of the mucolipin (TRPML) and TRPV subfamilies of transient receptor potential (TRP) cation channels. Based on sequence similarities of the pore forming regions and on structure-function evidence, we hypothesized that the pore forming domains of TRPML and TRPV5/TRPV6 channels have similarities that indicate possible functional interactions between these TRP channel subfamilies. Here we show that TRPML3 and TRPV5 associate to form a novel heteromeric ion channel. This novel conductance is detectable under conditions that do not activate either TRPML3 or TRPV5. It has pharmacological similarity with TRPML3 and requires functional TRPML3 as well as functional TRPV5. Single channel analyses revealed that TRPML3 and TRPV5 heteromers have different features than the respective homomers, and furthermore, that they occur in potentially distinct stoichiometric configurations. Based on overlapping expression of TRPML3 and TRPV5 in the kidney and the inner ear, we propose that TRPML3 and TRPV5 heteromers could have a biological function in these organs.