Referenced in: none

Automatically associated channels: Kir5.1

Title: PSD-95 mediates formation of a functional homomeric Kir5.1 channel in the brain.

Authors: Masayuki Tanemoto, Akikazu Fujita, Kayoko Higashi, Yoshihisa Kurachi

Journal, date & volume: Neuron, 2002 Apr 25 , 34, 387-97

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/11988170

Abstract
Homomeric assembly of Kir5.1, an inward-rectifying K+ channel subunit, is believed to be nonfunctional, although the subunit exists abundantly in the brain. We show that HEK293T cells cotransfected with Kir5.1 and PSD-95 exhibit a Ba(2+)-sensitive inward-rectifying K+ current. Kir5.1 coexpressed with PSD-95 located on the plasma membrane in a clustered manner, while the Kir5.1 subunit expressed alone distributed mostly in cytoplasm, probably due to rapid internalization. The binding of Kir5.1 with PSD-95 was prevented by protein kinase A (PKA)-mediated phosphorylation of its carboxyl terminus. The currents flowing through Kir5.1/PSD-95 were suppressed promptly and reversibly by PKA activation. Because the Kir5.1/PSD-95 complex was detected in the brain, this functional brain K+ channel is potentially a novel physiological target of PKA-mediated signaling.