The Ras-binding domain region of RGS14 regulates its functional interactions with heterotrimeric G proteins.

ABSTRACT: RGS14 is a 60 kDa protein that contains a regulator of G protein signaling (RGS) domain near its N-terminus, a central region containing a pair of tandem Ras-binding domains (RBD), and a GPSM (G protein signaling modulator) domain (a.k.a. Gi/o-Loco binding [GoLoco] motif) near its C-terminus. The RGS domain of RGS14 exhibits GTPase accelerating protein (GAP) activity toward Gαi/o proteins, while its GPSM domain acts as a guanine nucleotide dissociation inhibitor (GDI) on Gαi1 and Gαi3. In the current study, we investigate the contribution of different domains of RGS14 to its biochemical functions. Here we show that the full-length protein has a greater GTPase activating activity but a weaker inhibition of nucleotide dissociation relative to its isolated RGS and GPSM regions, respectively.

SUBMITTER: Zhao P 

PROVIDER: S-EPMC3739966 | biostudies-literature | 2013 Jun

REPOSITORIES: biostudies-literature