DNA-Directed RNA Polymerases I, II, and III Subunit RPABC5

Dihydrorifampicin, a rifampicin derivative hydrogenated at the 18-19 carbon atoms of the aliphatic ansa chain of the rifampicin molecule, inhibits the enzymatic activity of RNA polymerases I and II, isolated from the nuclei of avian tumor cells (Rous sarcoma) and from the human tumor cell line HEp-2. The RNA polymerases from these tumors have been separated and partially purified by chromatography on DEAE Sephadex A-25 and characterized by the sensitivity to α-amanitin. The [3H]UMP-labeled ribonucleic acids synthesized in the isolated nuclei of Rous sarcoma cells in the presence and absence of DHR were analyzed by sedimentation analysis in sucrose density gradients. It was found that the synthesis of rRNAs and mRNAs is very significantly inhibited by dihydrorifampicin, whereas the synthesis of tRNAs is much less inhibited at the same DHR concentration (100μg/ml). The observed cytostatic effect of DHR on the growth of human tumor cells HEp-2 and embryonic cells in culture is apparently mediated by the selective inhibition of RNA polymerases I and II in human and avian cells. The relationship between the molecular structure of DHR and its affinity to RNA polymerases of eukaryotic cells is discussed.

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Degree of inhibition of eukaryotic DNA-dependent RNA polymerases by thuringiensin

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19810673 ◽

1981 ◽

Vol 46 (3) ◽

pp. 673-677

Author(s):

Květa Horská ◽

Karel Šebesta

Keyword(s):

Rna Polymerases ◽

Calf Thymus ◽

Eukaryotic Dna

It was shown in experiments with purified DNA-dependent RNA polymerases from calf thymus that the inhibition of these enzymes caused by thuringiensin is competitive with respect to ATP. Enzyme AI is more sensitive to the inhibitor (Ki = 0.34 μm) than enzyme B (Ki = 1.49 μm).This finding eliminates the discrepancies with respect to this subject which exist in literature.

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Transcription of 4′-thioDNA templates to natural RNA in vitro and in mammalian cells

Chemical Communications ◽

10.1039/c4cc08862j ◽

2015 ◽

Vol 51 (37) ◽

pp. 7887-7890 ◽

Cited By ~ 17

Author(s):

Hideto Maruyama ◽

Kazuhiro Furukawa ◽

Hiroyuki Kamiya ◽

Noriaki Minakawa ◽

Akira Matsuda

Keyword(s):

Nucleic Acids ◽

Mammalian Cells ◽

Genetic Material ◽

Rna Polymerases ◽

Chemically Modified ◽

Biological Studies ◽

Modified Nucleic Acids

Synthetic chemically modified nucleic acids, which are compatible with DNA/RNA polymerases, have great potential as a genetic material for synthetic biological studies.

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