eat-11 encodes GPB-2, a G beta(5) ortholog that interacts with G(o)alpha and G(q)alpha to regulate C-elegans behavior

In C. elegans, a G(o)/G(q) signaling network regulates locomotion and egg l aying [1-8], Genetic analysis shows that activated Ca2+/calmodulin-dependen t protein kinase II (CaMKII) is suppressed by perturbations of this network , which include loss of the GOA-1 G(o)alpha, DGK-1 diacylglycerol kinase, E AT-16 16 protein gamma subunit-like (GGL)-containing RGS protein, or an uni dentified protein encoded by the gene eat-11 [9], We cloned eat-11 and repo rt that it encodes the G beta (5) ortholog GPB-2, Gp, binds specifically to GGL-containing RGS proteins, and the G beta (5)/RGS complex can promote th e GTP-hydrolyzing activity of G alpha subunits [10, 11], However, little is known about how this interaction affects G protein signaling in vivo. In a ddition to EAT-16, the GGL-containing RGS protein EGL-10 participates in G( o)/G(q) signaling; EGL-10 appears to act as an RGS for the GOA-1 G,cw, whil e EAT-16 appears to act as an RGS for the EGL-30 G(q)alpha [4, 5], We have combined behavioral, electrophysiological, and pharmacological approaches t o show that GPB-2 is a central member of the G(o)/G(q) network and that GPB -2 may interact with both the EGL-10 and EAT-16 RGS proteins to mediate the opposing activities of G,cw and G,a. These interactions provide a mechanis m for the modulation of behavior by antagonistic G protein networks.