Title: The G-protein-gated atrial K+ channel IKACh is a heteromultimer of two inwardly rectifying K(+)-channel proteins.

Authors: G Krapivinsky, E A Gordon, K Wickman, B Velimirovíc, L Krapivinsky, D E Clapham

Journal, date & volume: Nature, 1995 Mar 9 , 374, 135-41

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/7877685

Abstract
Heart rate is slowed in part by acetylcholine-dependent activation of a cardiac potassium (K+) channel, IKACh. Activated muscarinic receptors stimulate IKACh via the G-protein beta gamma-subunits. It has been assumed that the inwardly rectifying K(+)-channel gene, GIRK1, alone encodes IKACh. It is now shown that IKACh is a heteromultimer of two distinct inwardly rectifying K(+)-channel subunits, GIRK1 and a newly cloned member of the family, CIR.