Characterization of a factor that can prevent random transcription of cloned rDNA and its probable relationship to poly(ADP-ribose) polymerase.

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.

• 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.)

Chemical References

• DNA, Ribosomal
• Transcription Factors
• Poly(ADP-ribose) Polymerases
• NAD+ Nucleosidase
• DNA Topoisomerases, Type I

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)