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Updated: Aug 7, 2026

RhoC GTPase Activation Assay
Published on: August 22, 2010
Interaction of mastoparan with the low molecular mass GTP-binding proteins rho/rac
1Pharmakologisches Institut, Universitätsklinikums Essen, Germany.
Abstract:
Mastoparan, which has been shown to active G proteins, inhibits the ADP-ribosylation of 20 kDa human platelet membrane proteins catalyzed by Clostridium botulinum exoenzyme C3 half-maximally and maximally (90%) at 20 and 100 microM concentrations, respectively. Inhibition of ADP-ribosylation was enhanced by GTP-gamma S. Mastoparan increased GTP hydrolysis by porcine brain rho protein and stimulated GTP binding in a concentration dependent manner. The data suggest that mastoparan not only interacts with heterotrimeric G proteins but also with low molecular mass GTP-binding proteins of the rho/rac family.
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