Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P00750 (PLA)
 16,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To explore the interaction of tumor promoters and sarcoma virus transformation with cellular regulatory mechanisms, we have studied induction of plasminogen activator synthesis by these agents in a background of changing cyclic nucleotide concentrations. We have confirmed the original report of Wigler and Weinstein (Nature, 259: 232, 1976) that phorbol-12-myristate-13-acetate (PMA), a potent tumor promoter, induces high levels of plasminogen activator production by chick embryo fibroblasts. Sarcoma virus transformation sensitizes the fibroblasts by lowering the threshold concentration for response to the action of PMA, and the effects of transformation and PMA on plasminogen activator synthesis are synergistic rather than additive. The plasminogen activators produced in the PMA-, virus-induced, or synergistically stimulated cultures are indistinguishable. Enzyme production in all three conditions is strongly but reversibly inhibited when cyclic nucleotide levels are raised by exposure to cyclic adenosine-3':5'-monophosphate or cholera toxin. A substantial fraction of the morphological effect that accompanies transformation is not affected by concentrations of cyclic nucleotides that suppress plasminogen activator production, and the two phenomena are therefore at least partially independent expressions of transformation in this system.
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PMID:Modulation of plasminogen activator synthesis in chick embryo fibroblasts by cyclic nucleotides and phorobol myristate acetate. 21 31

The plasminogen activator was purified to the extent of 150-fold from 20,000 x g supernatant of Yoshida ascites Sarcoma by ammonium sulphate precipitation at 33% saturation followed by affinity chromatography on p-aminobenzamidine-Sepharose 4B. The specific activity of the purified activator was 10,260 IU/mg expressed in terms of International units of urokinase, the known activator of plasminogen. The activator was homogeneous by polyacrylamide slab gel electrophoresis with an apparent molecular weight 75 kDa by gel filtration on Sephadex G-100. Analysis by SDS-polyacrylamide gel electrophoresis under reducing conditions, revealed the presence of two subunits of about 48 and 29 kDa. The activator displayed binding preference to fibrin and was immunologically distinguishable from urokinase, indicating that it could be of non-urokinase origin. The preparation further revealed similarity to standard tissue plasminogen activator with respect to fibrin binding and immunological cross reactivity.
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PMID:Isolation and purification of plasminogen activator from Yoshida ascites Sarcoma of rats. 190 68