title: Induction of collagenase production in U937 cells by phorbol ester and partial purification of the induced enzyme.
abstract: The U937 cell line is a monoblast-like cell line that can be induced to differentiate when treated with phorbol ester or a variety of other agents. Collagenase was detected in the media of U937 cell cultures after treatment with phorbol myristate acetate (PMA) at concentrations of 5 ng/mL or greater. In general, no collagenase was detected in the media of untreated cells. The induced collagenase cleaved native type I collagen into the 3/4 and 1/4-length fragments and showed the inhibition by ethylenediaminetetraacetic acid characteristic of the action of mammalian collagenases. Collagenase activity could be detected in the media of treated cells 12-18 h after the addition of PMA. Secretion of collagenase continued for 2-3 days after PMA addition. The production of collagenase by PMA-treated U937 cells was inhibited by actinomycin D and cycloheximide, suggesting that the induction of the enzyme is the result of de novo synthesis. The collagenase secreted by U937 cells induced with PMA has been purified 12-fold by using DEAE-Sephacel followed by wheat germ agglutinin-agarose chromatography. The apparent molecular mass of this U937 collagenase, determined by gel filtration chromatography on the partially purified enzyme, was 29-36 kilodaltons.
mesh_terms: D002460:Cell Line; D004790:Enzyme Induction; D005033:Ethylmaleimide / Q000494:pharmacology; D006801:Humans; D007700:Kinetics; D003012:Microbial Collagenase / Q000096:biosynthesis* / Q000302:isolation & purification / Q000378:metabolism; D008970:Molecular Weight; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology*
chemical_list: D003012:Microbial Collagenase; D013755:Tetradecanoylphorbol Acetate; D005033:Ethylmaleimide