Effect of drugs on deoxyribonucleic acid synthesis in isolated mammalian cell nuclei. Comparison with partially purified deoxyribonucleic acid polymerases.
In order to ascertain the identity of the DNA-dependent DNA polymerase responsible for the observed DNA synthesis in nuclei isolated from baby-hamster kidney (BHK-21/C13) cells a comparative study was carried out on the effects of some drugs, reported to influence DNA synthesis, on DNA synthesis catalysed by these nuclei and by partially purified DNA polymerase-alpha and -beta. In all cases DNA synthesis by isolated nuclei and polymerase-alpha was inhibited to similar extents by N-ethylmaleimide, p-hydroxymercuribenzoate, novobiocin, heparin and phosphonoacetic acid; polymerase-beta was much less affected by these compounds. Ethidium bromide inhibited all DNA synthesis to similar extents, although at low concentrations (about 2 microgram/ml) synthesis in isolated nuclei was stimulated. The results are discussed in relation to the proposal that DNA polymerase-alpha catalyses the covalent extension of Okazaki fragments that these nuclei carry out in vitro.
D000818:Animals; D002458:Cell Fractionation; D002460:Cell Line; D002467:Cell Nucleus / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D006224:Cricetinae; D004247:DNA / Q000096:biosynthesis*; D004256:DNA Polymerase I / Q000302:isolation & purification; D004257:DNA Polymerase II / Q000302:isolation & purification; D004259:DNA-Directed DNA Polymerase / Q000378:metabolism*; D007668:Kidney; D013439:Sulfhydryl Reagents / Q000494:pharmacology
D013439:Sulfhydryl Reagents; D004247:DNA; D004256:DNA Polymerase I; D004257:DNA Polymerase II; D004259:DNA-Directed DNA Polymerase