Premium
Hormonal regulation of pituitary GH 3 cell K + channels by G k is mediated by its α‐subunit
Author(s) -
Codina Juan,
Grenet Dagoberto,
Yatani Atsuko,
Birnbaumer Lutz,
Brown Arthur M.
Publication year - 1987
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/0014-5793(87)80765-2
Subject(s) - adenylyl cyclase , transducin , g alpha subunit , g protein , gtp' , phosphodiesterase , alpha (finance) , endocrinology , protein subunit , medicine , chemistry , beta (programming language) , biophysics , receptor , biology , biochemistry , enzyme , gene , construct validity , nursing , patient satisfaction , computer science , programming language
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 GH 3 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.