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The p53 tumor suppressor targets a novel regulator of G protein signaling.

ABSTRACT: Heterotrimeric G proteins transduce multiple growth-factor-receptor-initiated and intracellular signals that may lead to activation of the mitogen-activated or stress-activated protein kinases. Herein we report on the identification of a novel p53 target gene (A28-RGS14) that is induced in response to genotoxic stress and encodes a novel member of a family of regulators of G protein signaling (RGS) proteins with proposed GTPase-activating protein activity. Overexpression of A28-RGS14p protein inhibits both Gi- and Gq-coupled growth-factor-receptor-mediated activation of the mitogen-activated protein kinase signaling pathway in mammalian cells. Thus, through the induction of A28-RGS14, p53 may regulate cellular sensitivity to growth and/or survival factors acting through G protein-coupled receptor pathways.

SUBMITTER: Buckbinder L

PROVIDER: S-EPMC21521 | biostudies-literature | 1997 Jul

REPOSITORIES: biostudies-literature

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The p53 tumor suppressor targets a novel regulator of G protein signaling.

Buckbinder L L Velasco-Miguel S S Chen Y Y Xu N N Talbott R R Gelbert L L Gao J J Seizinger B R BR Gutkind J S JS Kley N N

Proceedings of the National Academy of Sciences of the United States of America 19970701 15

Heterotrimeric G proteins transduce multiple growth-factor-receptor-initiated and intracellular signals that may lead to activation of the mitogen-activated or stress-activated protein kinases. Herein we report on the identification of a novel p53 target gene (A28-RGS14) that is induced in response to genotoxic stress and encodes a novel member of a family of regulators of G protein signaling (RGS) proteins with proposed GTPase-activating protein activity. Overexpression of A28-RGS14p protein in ...[more]

PMID: 9223279

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