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The third gamma subunit of the gamma-aminobutyric acid type A receptor family.

ABSTRACT: Cloned cDNAs encoding a member of the gamma-aminobutyric acid type A receptor gamma-subunit class were isolated from rat-brain-mRNA-derived libraries. The gamma 3 mRNA is present in cortex, claustrum, caudate putamen, and some thalamic nuclei, particularly the medial geniculate nucleus, where it is the predominant gamma-subunit transcript. The gamma 3 gene is expressed at very low levels in cerebellum and hippocampus. In coexpression experiments with the alpha 1 and beta 2 subunits, gamma 3 imparts benzodiazepine binding to gamma-aminobutyric acid type A receptors and forms gamma-aminobutyric acid-gated benzodiazepine-modulated chloride channels that exhibit a larger conductance than alpha 1 beta 2 receptor channels. Furthermore, the presence of gamma 3 in place of gamma 2 in alpha 1 beta 2 gamma x receptors generates a marked decrease in the affinity of agonists while leaving the affinity of antagonists or negative modulators largely unaffected.

SUBMITTER: Herb A

PROVIDER: S-EPMC48465 | biostudies-other | 1992 Feb

REPOSITORIES: biostudies-other

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The third gamma subunit of the gamma-aminobutyric acid type A receptor family.

Herb A A Wisden W W Lüddens H H Puia G G Vicini S S Seeburg P H PH

Proceedings of the National Academy of Sciences of the United States of America 19920201 4

Cloned cDNAs encoding a member of the gamma-aminobutyric acid type A receptor gamma-subunit class were isolated from rat-brain-mRNA-derived libraries. The gamma 3 mRNA is present in cortex, claustrum, caudate putamen, and some thalamic nuclei, particularly the medial geniculate nucleus, where it is the predominant gamma-subunit transcript. The gamma 3 gene is expressed at very low levels in cerebellum and hippocampus. In coexpression experiments with the alpha 1 and beta 2 subunits, gamma 3 impa ...[more]

PMID: 1311098

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