title: Botulinum C2 toxin potentiates activation of the neutrophil oxidase. Further evidence of a role for actin polymerization.
abstract: Botulinum C2 toxin was employed as a specific inhibitor of actin polymerization in rat neutrophils to determine its role in oxidase activation. This toxin was shown to inhibit actin polymerization and the microfilament-dependent function, phagocytosis. Oxidase activation in response to the chemotactic peptide, f-Met-Leu-Phe (FMLP) was enhanced approx. 3-fold. The enhancement by C2 toxin did not occur in cells pretreated with cytochalasin B. C2 toxin had no significant effect on the FMLP-induced intracellular Ca2+ rise. These data are consistent with an inhibitory role for actin polymerization in oxidase activation.
mesh_terms: D000199:Actins / Q000097:blood*; D000818:Animals; D001704:Biopolymers; D001905:Botulinum Toxins / Q000494:pharmacology*; D002118:Calcium / Q000097:blood; D004357:Drug Synergism; D004789:Enzyme Activation / Q000187:drug effects; D005089:Exocytosis / Q000187:drug effects; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D009504:Neutrophils / Q000201:enzymology*; D010088:Oxidoreductases / Q000097:blood*; D010587:Phagocytosis / Q000187:drug effects; D051381:Rats
chemical_list: D000199:Actins; D001704:Biopolymers; D009240:N-Formylmethionine Leucyl-Phenylalanine; D010088:Oxidoreductases; D001905:Botulinum Toxins; D002118:Calcium