Activation of inward rectifying K+ channels by GABA-B receptors in Xenopus oocytes coexpressing the rat cerebellar poly(A)+ RNA with the cloned GIRK1 and GIRK2

The inwardly rectifying K(+) channel subunit GIRK1 rescues the GIRK2 weaver phenotype.

The weaver (wv) gene has been identified as a glycine to serine substitution at residue 156 in the H5 region of inwardly rectifying K(+) channel, GIRK2. The mutation is permissive for the expression of homotetrameric channels that are nonselective for cations and G-protein-independent. Coexpression of GIRK2wv with GIRK1, GIRK2, or GIRK3 in Xenopus oocytes along with expression of subunit combin...

Physiological Roles of Inward-Rectifying K+ Channels.

Cloned human and rat galanin GALR3 receptors. Pharmacology and activation of G-protein inwardly rectifying K+ channels.

The neuropeptide galanin has been implicated in the regulation of processes such as nociception, cognition, feeding behavior, and hormone secretion. Multiple galanin receptors are predicted to mediate its effects, but only two functionally coupled receptors have been reported. We now report the cloning of a third galanin receptor distinct from GALR1 and GALR2. The receptor, termed GALR3, was is...

Defective gamma-aminobutyric acid type B receptor-activated inwardly rectifying K+ currents in cerebellar granule cells isolated from weaver and Girk2 null mutant mice.

Stimulation of inhibitory neurotransmitter receptors, such as gamma-aminobutyric acid type B (GABAB) receptors, activates G protein-gated inwardly rectifying K+ channels (GIRK) which, in turn, influence membrane excitability. Seizure activity has been reported in a Girk2 null mutant mouse lacking GIRK2 channels but showing normal cerebellar development as well as in the weaver mouse, which has ...

Functional Effects of the Mouse weaver Mutation on G Protein–Gated Inwardly Rectifying K+ Channels

The weaver mutation corresponds to a substitution of glycine to serine in the H5 region of a G protein-gated inwardly rectifying K+ channel gene (GIRK2). By studying mutant GIRK2 weaver homomultimeric channels and heteromultimeric channels comprised of GIRK2 weaver and GIRK1 in Xenopus oocytes, we found that GIRK2 weaver homomultimeric channels lose their selectivity for K+ ions, giving rise to...