Interaction of G protein Gbetagamma dimers with small GTP-binding proteins of the Rho family.
Gbetagamma dimers of heterotrimeric G proteins have been shown to be important for the translocation of cytosolic proteins to membranes. The involvement of Gbetagamma in those signaling processes mediated by small GTP-binding proteins of the Rho family was studied using purified proteins. We showed specific binding of bovine brain Gbetagamma to immobilized GST-Rho fusion proteins. In addition, brain Gbetagamma, but not transducin Gbetagamma, was able to inhibit GTPgammaS binding to GST-Rho in a concentration-dependent manner. GTPgammaS binding to GST-Rac was also decreased by brain Gbetagamma whereas nucleotide binding to GST-Cdc42 was not changed. We conclude that Gbetagamma dimers may participate in the process of membrane attachment and/or other regulations of Rho and Rac.
Harhammer
R
R
Institut für Pharmakologie, Freie Universität Berlin, Germany.
Gohla
A
A
Schultz
G
G
D000818:Animals; D001704:Biopolymers; D002417:Cattle; D019204:GTP-Binding Proteins / Q000378:metabolism*; D006150:Guanine Nucleotides / Q000378:metabolism*; D011485:Protein Binding; D015398:Signal Transduction
D001704:Biopolymers; D006150:Guanine Nucleotides; D019204:GTP-Binding Proteins