Ric-8 regulation of heterotrimeric G proteins. (June 2013)

• Record Type: Journal Article
• Authors: Tall, Gregory G.
• Is Part Of: Journal of receptor and signal transduction research. Volume 33:Number 3(2013)
• Page Start: 139
• Page End: 143
• Publication Date: 2013-06
• Subjects: Cell receptors -- Periodicals; Cellular signal transduction -- Periodicals; 571.6
• DOI: 10.3109/10799893.2013.763828
• Languages: English
• ISSNs: 1079-9893

Abstract

<abstract> <title>Abstract</title> <p>Resistance to inhibitors of cholinesterase 8 proteins (Ric-8A and Ric-8B) collectively bind the four classes of heterotrimeric G protein α subunits. Ric-8A and Ric-8B act as non-receptor guanine nucleotide exchange factors (GEFs) toward the Gα subunits that each binds <italic>in vitro</italic> and seemingly regulate diverse G protein signaling systems in cells. Combined evidence from worm, fly and mammalian systems has shown that Ric-8 proteins are required to maintain proper cellular abundances of G proteins. Ric-8 proteins support G protein levels by serving as molecular chaperones that promote Gα subunit biosynthesis. In this review, the evidence that Ric-8 proteins act as non-receptor GEF activators of G proteins in signal transduction contexts will be weighed against the evidence supporting the molecular chaperoning function of Ric-8 in promoting G protein abundance. I will conclude by suggesting that Ric-8 proteins may act in either capacity in specific contexts. The field awaits additional experimentation to delineate the putative multi-functionality of Ric-8 towards G proteins in cells.</p> </abstract>