We immunized rabbits with purified guanine nucleotide-binding proteins (G proteins) from bovine brain and obtained an antiserum, RV3, that reacts specifically with the alpha subunit (39 kDa) of a G protein of unknown function, termed Go, as well as with the beta subunit (35 kDa) common to all G proteins. RV3 showed no crossreactivity with the alpha subunits of the stimulatory (Gs) or inhibitory...

The principal GTP-binding protein (G-protein) from squid (Loligo forbesi) photoreceptor membranes has been identified by amino acid sequencing. The heterotrimeric protein was purified by detergent solubilization and ion-exchange chromatography. The amino acid sequence of the G-protein alpha-subunit (G-alpha) indicates that this subunit is closely related to the recently characterized Gq subgrou...

introduction: g-proteins have an important role in the cell signaling of numerous receptors. the situation of g-proteins in health and disease and their critical role in the development of diabetic side effects is an interested scientific field. here, the changes in the expression of g-protein subunits (gαi, gαs and gβ) were evaluated in hyperglycemic situation of pc12 cells as a cellular model...

Mechanisms for heterotrimeric G protein activation that do not rely on G protein coupled receptor activation are becoming increasingly apparent. We recently identified beta gamma subunit-binding peptides that we proposed bound to a "hot spot" on beta gamma subunits, stimulating G protein dissociation without stimulating nucleotide exchange and activating G protein signaling in intact cells. AGS...

The Ca channel b subunit has been shown to reduce the magnitude of G-protein inhibition of Ca channels. However, neither the specificity of this action to different forms of G-protein inhibition nor the mechanism underlying this reduction in response is known. We have reported previously that coexpression of the Ca channel b3 subunit causes M2 muscarinic receptor-mediated inhibition of a1B Ca 2...