Title : A C-terminal mutant of the G protein beta subunit deficient in the activation of phospholipase C-beta - Zhang_1996_J.Biol.Chem_271_20208 |
Author(s) : Zhang S , Coso OA , Collins R , Gutkind JS , Simonds WF |
Ref : Journal of Biological Chemistry , 271 :20208 , 1996 |
Abstract :
The molecular mechanism by which the G protein betagamma complex modulates multiple mammalian effector pathways is unknown. Homolog-scanning mutagenesis of the G protein beta subunit was employed to identify residues critical for the activation of phospholipase C-beta2 (PLC-beta2). A series of chimeras was made by introducing small segments of the Dictyostelium beta subunit into a background of mammalian beta1 and tested in COS cell cotransfection assays for their ability to activate PLC-beta2 and assemble with mammalian gamma2. A chimera that contained four Dictyostelium beta substitutions within the C-terminal 14 residues was unable to activate PLC-beta2 when cotransfected with gamma, despite its demonstrable expression in a gamma-dependent manner. Cotransfection of the mutant blocked m2 muscarinic receptor activation of PLC by a pertussis toxin-sensitive pathway. This C-terminal mutant retained the ability, however, to stimulate the mitogen-activated protein kinase pathway. These results imply that activation of different betagamma-responsive effectors is mediated by distinct domains. |
PubMedSearch : Zhang_1996_J.Biol.Chem_271_20208 |
PubMedID: 8702747 |
Zhang S, Coso OA, Collins R, Gutkind JS, Simonds WF (1996)
A C-terminal mutant of the G protein beta subunit deficient in the activation of phospholipase C-beta
Journal of Biological Chemistry
271 :20208
Zhang S, Coso OA, Collins R, Gutkind JS, Simonds WF (1996)
Journal of Biological Chemistry
271 :20208