Click here to close Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly. We suggest using a current version of Chrome, FireFox, or Safari.
XB-ART-41981
J Biol Chem 2010 Jun 25;28526:19884-90. doi: 10.1074/jbc.M110.113936.
Show Gene links Show Anatomy links

Forward genetic analysis reveals multiple gating mechanisms of TRPV4.

Loukin S , Su Z , Zhou X , Kung C .


Abstract
TRPV4 is a polymodal cation channel gain-of-function (GOF) allele which causes skeletal dysplasia in humans. To better understand its gating, we screened for additional GOF alleles based on their ability to block yeast proliferation. Repeatedly, only a limited number of such growth-blocking mutations were isolated. Expressed in oocytes, wild-type channels can be strongly activated by either hypotonicity or exposure to the potent agonist 4alphaPDD, although the GOF channels behaved as if they were fully prestimulated as well as lacking a previously uncharacterized voltage-dependent inactivation. Five of six mutations occurred at or near the inner ends of the predicted core helices, giving further direct evidence that this region indeed forms the main intracellular gate in TRP channels. Surprisingly, both wild-type channels as well as these GOF channels maintain strong steady-state outward rectification that is not due to a Ca(2+) block, as has been proposed elsewhere. We conclude that TRPV4 contains an additional voltage-dependent gating mechanism in series with the main intracellular gate.

PubMed ID: 20424166
PMC ID: PMC2888399
Article link: J Biol Chem
Grant support: [+]

Species referenced: Xenopus
Genes referenced: trpv4

References [+] :
Auer-Grumbach, Alterations in the ankyrin domain of TRPV4 cause congenital distal SMA, scapuloperoneal SMA and HMSN2C. 2010, Pubmed