Referenced in: none

Automatically associated channels: KChIP2 , Kv1.4 , Kv3.1 , Kv4.3

Title: Angiotensin receptor type 1 forms a complex with the transient outward potassium channel Kv4.3 and regulates its gating properties and intracellular localization.

Authors: Sergey V Doronin, Irina A Potapova, Zhongju Lu, Ira S Cohen

Journal, date & volume: J. Biol. Chem., 2004 Nov 12 , 279, 48231-7

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/15342638

Abstract
We report a novel signal transduction complex of the angiotensin receptor type 1. In this complex the angiotensin receptor type 1 associates with the potassium channel alpha-subunit Kv4.3 and regulates its intracellular distribution and gating properties. Co-localization of Kv4.3 with angiotensin receptor type 1 and fluorescent resonance energy transfer between those two proteins labeled with cyan and yellow-green variants of green fluorescent protein revealed that Kv4.3 and angiotensin receptor type I are located in close proximity to each other in the cell. The angiotensin receptor type 1 also co-immunoprecipitates with Kv4.3 from canine ventricle or when co-expressed with Kv4.3 and its beta-subunit KChIP2 in human embryonic kidney 293 cells. Treatment of the cells with angiotensin II results in the internalization of Kv4.3 in a complex with the angiotensin receptor type 1. When stimulated with angiotensin II, angiotensin receptors type 1 modulate gating properties of the remaining Kv4.3 channels on the cell surface by shifting their activation voltage threshold to more positive values. We hypothesize that the angiotensin receptor type 1 provides its internalization molecular scaffold to Kv4.3 and in this way regulates the cell surface representation of the ion channel.