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Gbeta5 recruits R7 RGS proteins to GIRK channels to regulate the timing of neuronal inhibitory signaling.

ABSTRACT: The type 5 G protein beta subunit (Gbeta5) can form complexes with members of the regulator of G protein signaling 7 (RGS7) family, but its relevance to neuronal G protein signaling is unclear. We found that mouse RGS7-Gbeta5 complexes bound to G protein-gated potassium channels and facilitated their functional coupling to GABA(B) receptors in neurons. Our findings identify a compartmentalization mechanism that is critical for ensuring high temporal resolution of neuronal G protein signaling.

SUBMITTER: Xie K

PROVIDER: S-EPMC2876203 | biostudies-literature | 2010 Jun

REPOSITORIES: biostudies-literature

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Gbeta5 recruits R7 RGS proteins to GIRK channels to regulate the timing of neuronal inhibitory signaling.

Xie Keqiang K Allen Kevin L KL Kourrich Saïd S Colón-Saez José J Thomas Mark J MJ Wickman Kevin K Martemyanov Kirill A KA

Nature neuroscience 20100509 6

The type 5 G protein beta subunit (Gbeta5) can form complexes with members of the regulator of G protein signaling 7 (RGS7) family, but its relevance to neuronal G protein signaling is unclear. We found that mouse RGS7-Gbeta5 complexes bound to G protein-gated potassium channels and facilitated their functional coupling to GABA(B) receptors in neurons. Our findings identify a compartmentalization mechanism that is critical for ensuring high temporal resolution of neuronal G protein signaling. ...[more]

PMID: 20453851

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