[Effect of actinomycin D on purified DNA-dependent RNA polymerases from normal and neoplastic tissues].
The effect of low concentrations of actinomycin D was investigated, using two forms of DNA-dependent RNA polymerase (A and B) purified from normal tissues and experimental tumours, in the presence either of Mn2+ or Mg2+, and homologous DNA. The A enzyme activity was strongly inhibited by the antibiotic in presence of Mg2+ and much less in presence of Mn2+. The B enzyme activity was almost suppressed in presence of both cations. The results here reported provide support that the actinomycin D induce a cellular damage of the same extent in normal and tumour tissues.
D000818:Animals; D002279:Carcinoma 256, Walker / Q000201:enzymology; D012321:DNA-Directed RNA Polymerases / Q000302:isolation & purification*; D003609:Dactinomycin / Q000494:pharmacology*; D007668:Kidney / Q000201:enzymology*; D008099:Liver / Q000201:enzymology*; D008114:Liver Neoplasms, Experimental / Q000201:enzymology; D008274:Magnesium / Q000494:pharmacology; D008345:Manganese / Q000494:pharmacology; D009101:Multiple Myeloma / Q000201:enzymology; D009369:Neoplasms / Q000201:enzymology*; D051381:Rats; D013154:Spleen / Q000201:enzymology*
D003609:Dactinomycin; D008345:Manganese; D012321:DNA-Directed RNA Polymerases; D008274:Magnesium
Effetto dell'actinomicina D sulle RNA polimerasi DNA-dipendenti purificate da tessuti normali e neoplastici.