Referenced in: none

Automatically associated channels: TRP , TRPV , TRPV3

Title: Crystal structure of the N-terminal ankyrin repeat domain of TRPV3 reveals unique conformation of finger 3 loop critical for channel function.

Authors: Di-Jing Shi, Sheng Ye, Xu Cao, Rongguang Zhang, Kewei Wang

Journal, date & volume: Protein Cell, 2013 Dec , 4, 942-50

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/24248473

Abstract
In all six members of TRPV channel subfamily, there is an ankyrin repeat domain (ARD) in their intracellular N-termini. Ankyrin (ANK) repeat, a common motif with typically 33 residues in each repeat, is primarily involved in protein-protein interactions. Despite the sequence similarity among the ARDs of TRPV channels, the structure of TRPV3-ARD, however, remains unknown. Here, we report the crystal structure of TRPV3-ARD solved at 1.95 Å resolution, which reveals six-ankyrin repeats. While overall structure of TRPV3-ARD is similar to ARDs from other members of TRPV subfamily; it, however, features a noticeable finger 3 loop that bends over and is stabilized by a network of hydrogen bonds and hydrophobic packing, instead of being flexible as seen in known TRPV-ARD structures. Electrophysiological recordings demonstrated that mutating key residues R225, R226, Q255, and F249 of finger 3 loop altered the channel activities and pharmacology. Taken all together, our findings show that TRPV3-ARD with characteristic finger 3 loop likely plays an important role in channel function and pharmacology.