Abstract |
A factor which eliminated nonspecific transcription of cloned rat rDNA was extensively purified from rat mammary adenocarcinoma ascites cells by successive fractionations on DEAE-Sephadex and heparin-Sepharose columns. The fractions containing RNA polymerase I (HS-B) and fractions eluting thereafter (HS-C) from the heparin-Sepharose column were pooled separately. Addition of HS-C to HS-B prevented random transcription of rDNA and yielded an accurate rDNA transcript with negligible non-specific transcription. The factor was essentially homogeneous and corresponded to Poly(ADP-ribose) polymerase with respect to molecular weight, dependence on DNA for its activity and its ability to undergo auto ADP-ribosylation. The total amount of protein in the transcription assay was approximately 2 micrograms, which indicates a high degree of purity of all the factors required for specific transcription of rDNA.
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Authors | R N Kurl, S T Jacob |
Journal | Nucleic acids research
(Nucleic Acids Res)
Vol. 13
Issue 1
Pg. 89-101
(Jan 11 1985)
ISSN: 0305-1048 [Print] England |
PMID | 2987793
(Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)
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Chemical References |
- DNA, Ribosomal
- Transcription Factors
- Poly(ADP-ribose) Polymerases
- NAD+ Nucleosidase
- DNA Topoisomerases, Type I
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Topics |
- Adenocarcinoma
(genetics)
- Animals
- Cloning, Molecular
- DNA Topoisomerases, Type I
(metabolism)
- DNA, Ribosomal
(genetics, metabolism)
- Mammary Neoplasms, Experimental
(genetics)
- Molecular Weight
- NAD+ Nucleosidase
(physiology)
- Poly(ADP-ribose) Polymerases
(physiology)
- Rats
- Subcellular Fractions
(physiology)
- Transcription Factors
(isolation & purification, pharmacology)
- Transcription, Genetic
(drug effects)
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