title: Apparent "activation" of protein kinases by okadaic acid class tumor promoters.
abstract: A cytosolic fraction of mouse brain gave two peaks of protein kinase activity on DEAE-cellulose column chromatography. The first peak of protein kinase corresponded to protein kinase C. The second peak contained protein kinases that were "activated" dose-dependently by the okadaic acid class tumor promoters, okadaic acid and dinophysistoxin-1. This "activation" was not achieved by other tumor promoters, such as 12-0-tetradecanoyl-phorbol-13-acetate, teleocidin, aplysiatoxin, or palytoxin. In addition, the second peak contained phosphatases. The phosphate liberation from phosphorylated histone type III-S by incubation with the second peak was inhibited by okadaic acid or dinophysistoxin-1, dose-dependently. The resulting apparent "activation" of protein kinases by okadaic acid is indicated and would imply a new pathway of tumor promotion on mouse skin.
authors.affiliation: Cancer Prevention Division, National Cancer Center Research Institute, Tokyo, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Sassa
authors.forename: W W
authors.initials: WW
authors.lastname: Richter
authors.forename: N
authors.initials: N
authors.lastname: Uda
authors.forename: M
authors.initials: M
authors.lastname: Suganuma
authors.forename: H
authors.initials: H
authors.lastname: Suguri
authors.forename: S
authors.initials: S
authors.lastname: Yoshizawa
authors.forename: M
authors.initials: M
authors.lastname: Hirota
authors.forename: H
authors.initials: H
authors.lastname: Fujiki
mesh_terms: D000818:Animals; D001921:Brain / Q000201:enzymology*; D002273:Carcinogens / Q000494:pharmacology*; D002848:Chromatography, DEAE-Cellulose; D003600:Cytosol / Q000201:enzymology; D004789:Enzyme Activation; D004988:Ethers, Cyclic / Q000494:pharmacology*; D007527:Isoenzymes / Q000378:metabolism; D007700:Kinetics; D051379:Mice; D019319:Okadaic Acid; D011494:Protein Kinases / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D002273:Carcinogens; D004988:Ethers, Cyclic; D007527:Isoenzymes; D019319:Okadaic Acid; D011494:Protein Kinases