Significance of phosphorylation/dephosphorylation of 46K protein(s) in regulation of superoxide anion production in intact guinea pig polymorphonuclear leukocytes.
Superoxide anion (O2-) production stimulated by concanavalin A (Con A) in guinea pig polymorphonuclear leukocytes (PMNL) was suppressed by addition of methyl-alpha-mannoside, a Con A inhibitor, and resumed upon readdition of Con A. The reversible change in the O2- production was assumed to reflect the change in NADPH oxidase activity measured for the 30,000 X g particulate fraction. The stimulation by Con A of the phosphorylation of 46K protein(s), as observed previously with several membrane-perturbing agents in parallel with an activation of NADPH oxidase in intact guinea pig PMNL (Okamura, N., et al. (1984) Arch. Biochem. Biophys. 228, 270-277), was also suppressed by methyl-alpha-mannoside and resumed upon readdition of Con A. Similar parallelism between the phosphorylation and NADPH oxidase activity was also observed in the case of stimulation by N-formyl-methionyl-leucyl-phenylalanine (FMLP) and phorbol 12-myristate 13-acetate (PMA), though both processes were reversible after the stimulation by FMLP but not reversible after that by PMA. Thus, such a parallelism observed in both intact PMNL and 30,000 X g particulate fraction indicates possible involvement of the protein phosphorylation in the regulation of the production of active oxygen metabolites in PMNL.
D000818:Animals; D003208:Concanavalin A / Q000494:pharmacology; D006168:Guinea Pigs; D007526:Isoelectric Point; D008362:Mannosides / Q000494:pharmacology; D008970:Molecular Weight; D009097:Multienzyme Complexes / Q000378:metabolism; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism; D009504:Neutrophils / Q000502:physiology*; D010750:Phosphoproteins / Q000502:physiology*; D013481:Superoxides / Q000096:biosynthesis*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D008362:Mannosides; D009097:Multienzyme Complexes; D010750:Phosphoproteins; D003208:Concanavalin A; D013481:Superoxides; D009240:N-Formylmethionine Leucyl-Phenylalanine; C023107:NADH oxidase; D009247:NADH, NADPH Oxidoreductases; D013755:Tetradecanoylphorbol Acetate