Hormonal regulation of pituitary GH3 cell K+ channels by Gk is mediated by its α‐subunit

FEBS Letters

Codina, Juan¹  Grenet, Dagoberto¹  Birnbaumer, Lutz¹  Yatani, Atsuko²  Brown, Arthur M.² 

[1] Department of Cell Biology, Baylor College of Medicine, Houston, TX 77030, USA;Department of Physiology and Molecular Biophysics, Baylor College of Medicine, Houston, TX 77030, USA

关键词: G-protein subunit;    Ligand-gated K+ channel;    Somatostatin receptor;    Muscarinic receptor;    Transmembrane signaling;    Coupling protein;    (Endocrine cell);   

DOI  :  10.1016/0014-5793(87)80765-2

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The resolved α-GTPγS (α*) and βγ-subunits of human erythrocyte G_k, the stimulatory regulatory component of hormone-responsive K⁺ channels, were tested for their potential stimulatory activities on the K⁺ channel of the endocrine GH₃ cell. Concentrations as low as 0.5 pM α_k* consistently activated K⁺ channels in isolated membrane patches, and saturating effects were obtained with 50 pM α_k*. In contrast 2000–4000 pM βγ was without effect. We conclude that G_k acts on K⁺ channels through its α-subunit in a manner akin to that of G_s acting on adenylyl cyclase and transducin acting on cGMP-specific phosphodiesterase of photo-receptor cells.

【 授权许可】

Unknown