Activation of G protein‐coupled inward rectifier K+ channels in brain neurons requires association of G protein βγ subunits with cell membrane

FEBS Letters

Kozasa, Tohru²  Nakajima, Shigehiro¹  Nakajima, Yasuko³ 

[1] Department of Pharmacology, University of Illinois at Chicago, College of Medicine, 808 South Wood Street, Chicago, IL 60612, USA;Department of Pharmacology, University of Texas, Southwestern Medical Center at Dallas, 5323 Harry Hines Blvd., Dallas, TX 75235, USA;Department of Anatomy and Cell Biology (M/C 512), University of Illinois at Chicago, College of Medicine, 808 South Wood Street, Chicago, IL 60612, USA

关键词: Inward rectifier K+ channel;    G protein subunit;    Prenylation;    Brain noradrenergic neuron;    Locus coeruleus;   

DOI  :  10.1016/0014-5793(96)00661-8

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

In cultured noradrenergic neurons from the rat locus coeruleus, application of recombinant G protein β ₁ γ ₂ subunits (30 nM) to the cytoplasmic side induced single channel activity similar to the somatostatin-induced single channel activity of G protein-coupled inward rectifier potassium channels (K_ir (G)). In contrast, recombinant GTPγS-activated, myristoylated α _i2 (100 nM) did not activate this brain K_ir (G). Application of β ₁ γ ₂C68S (30 nM or 150 nM), in which the cysteine residue fourth from the carboxyl terminus of γ ₂ was replaced by serine, failed to activate the brain K_ir(G). This mutant lacks prenylation which is required for the association of βγ subunit with the cell membrane. Thus, our results suggest that the association of βγ subunit with the cell membrane is a prerequisite for activating K_ir(G) channels.

【 授权许可】

Unknown