Importance of the G protein γ subunit in activating G protein‐coupled inward rectifier K+ channels
- 17 December 1999
- journal article
- Published by Wiley in FEBS Letters
- Vol. 463 (3) , 355-359
- https://doi.org/10.1016/s0014-5793(99)01656-7
Abstract
The G protein‐coupled inward rectifier K+ channel (GIRK) is activated by direct interaction with the heterotrimeric GTP‐binding protein βγ subunits (Gβγ). However, the precise role of Gβ and Gγ in GIRK activation remains to be elucidated. Using transient expression of GIRK1, GIRK2, Gβ1, and Gγ2 in human embryonic kidney 293 cells, we show that C‐terminal mutants of Gβ1, which do not bind to Gγ2, are still able to associate with GIRK, but these mutants are unable to induce activation of GIRK channels. In contrast, other C‐terminal mutants of Gβ1 that bind to Gγ2, are capable of activating the GIRK channel. These results suggest that Gγ plays a more important role than that of an anchoring device for the Gβγ‐induced GIRK activation.Keywords
This publication has 35 references indexed in Scilit:
- Identification of two forms of the γ subunit of G protein, γ10and γ11, in bovine lung and their tissue distribution in the ratFEBS Letters, 1998
- A Domain on the G Protein β Subunit Interacts with Both Adenylyl Cyclase 2 and the Muscarinic Atrial Potassium ChannelPublished by Elsevier ,1996
- Inhibition of an inwardly rectifying K+ channel by G-protein α-subunitsNature, 1996
- Carboxyl Terminal of G Protein β Subunit Is Required for Association with γ SubunitBiochemical and Biophysical Research Communications, 1995
- Gβγ Directly Binds to the Carboxyl Terminus of the G Protein-Gated Muscarinic K+ Channel, GIRK1Biochemical and Biophysical Research Communications, 1995
- G protein βγ subunit activates Ras, Raf, and MAP kinase in HEK 293 cellsFEBS Letters, 1995
- Heterologous Multimeric Assembly Is Essential for K+ Channel Activity of Neuronal and Cardiac G-Protein-Activated Inward RectifiersBiochemical and Biophysical Research Communications, 1995
- Cloning provides evidence for a family of inward rectifier and G‐protein coupled K+ channels in the brainFEBS Letters, 1994
- Activation of the cloned muscarinic potassium channel by G protein βγ subunitsNature, 1994
- A brain‐specific γ subunit of G protein freed from the corresponding β subunit under non‐denaturing conditionsFEBS Letters, 1994