Interaction of mastoparan with the low molecular mass GTP-binding proteins rho/rac.
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.
Pharmakologisches Institut, Universitätsklinikums Essen, Germany.
G
G
Koch
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B
Haberman
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C
Mohr
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I
Just
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K
Aktories
D036002:ADP Ribose Transferases / Q000037:antagonists & inhibitors; D000246:Adenosine Diphosphate Ribose / Q000378:metabolism; D000818:Animals; D001905:Botulinum Toxins; D003014:Clostridium botulinum / Q000201:enzymology; D019204:GTP-Binding Proteins / Q000737:chemistry / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins; D008565:Membrane Proteins / Q000737:chemistry / Q000502:physiology*; D008970:Molecular Weight; D010455:Peptides; D011485:Protein Binding; D013552:Swine; D014862:Wasp Venoms / Q000737:chemistry / Q000494:pharmacology*; D020744:rac GTP-Binding Proteins; D020743:rhoB GTP-Binding Protein
D036341:Intercellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D010455:Peptides; D014862:Wasp Venoms; D000246:Adenosine Diphosphate Ribose; C037500:mastoparan; D036002:ADP Ribose Transferases; C063007:exoenzyme C3, Clostridium botulinum; D001905:Botulinum Toxins; D019204:GTP-Binding Proteins; D020744:rac GTP-Binding Proteins; D020743:rhoB GTP-Binding Protein