Skip to main page content
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1995 Jun 23;270(25):15175-80.
doi: 10.1074/jbc.270.25.15175.

G Alpha 15 and G Alpha 16 Couple a Wide Variety of Receptors to Phospholipase C

Affiliations
Free article

G Alpha 15 and G Alpha 16 Couple a Wide Variety of Receptors to Phospholipase C

S Offermanns et al. J Biol Chem. .
Free article

Abstract

The murine G-protein alpha-subunit G alpha 15 and its human counterpart G alpha 16 are expressed in a subset of hematopoietic cells, and they have been shown to regulate beta-isoforms of inositide-specific phospholipase C. We studied the ability of a variety of receptors to interact with G alpha 15 and G alpha 16 by cotransfecting receptors and G-protein alpha-subunits in COS-7 cells. Activation of beta 2 adrenergic and muscarinic M2 receptors in cells expressing the receptors alone or together with G alpha q, G alpha 11, or G alpha 14 led to a very small stimulation of endogenous phospholipase C. However, when the receptors were coexpressed with G alpha 15 and G alpha 16, addition of appropriate ligands caused a severalfold increase in inositol phosphate production which was time- and dose-dependent. A similar activation of phospholipase C was observed when several other receptors which were previously shown to couple to members of the Gi and Gs family were coexpressed with G alpha 15/16. In addition, stimulation of inositol phosphate formation via receptors naturally coupled to phospholipase C was enhanced by cotransfection of G alpha 15 and G alpha 16. These data demonstrate that G alpha 15 and G alpha 16 are unique in that they can be activated by a wide variety of G-protein-coupled receptors. The ability of G alpha 15 and G alpha 16 to bypass the selectivity of receptor G-protein interaction can be a useful tool to understand the mechanism of receptor-induced G-protein activation. In addition, the promiscuous behavior of G alpha 15 and G alpha 16 toward receptors may be helpful in finding ligands corresponding to orphan receptors whose signaling properties are unknown.

Similar articles

See all similar articles

Cited by 102 articles

See all "Cited by" articles

Publication types

MeSH terms

LinkOut - more resources

Feedback