Xenopus transcription factor A promotes DNA reassociation.
We demonstrate by agarose gel electrophoresis and DNase I footprinting that Xenopus transcription factor A promotes DNA reassociation. This ability of factor A is dependent upon the domain-like structure of the protein. Digestion of factor A by papain results in a protein fragment which promotes DNA reassociation whereas a smaller fragment obtained by trypsin digestion does not. Although factor A requires zinc for specific binding to the 5 S RNA gene, the metal is not required for single-stranded DNA binding or promotion of DNA reassociation by this protein. The factor A-dependent renaturation of the 5 S RNA gene from its individual 32P end-labeled strands results in the proper gene conformation as evidenced by the restoration of the DNase I footprint characteristic of the intragenic control region. Alterations in DNase I cleavage patterns induced by factor A on the individual 5 S DNA strands are distinct from those induced by the protein on the duplex 5 S RNA gene. The ability of factor A to promote DNA reassociation further defines the possible roles of this protein in the formation of active transcription complexes and their maintenance during repeated rounds of transcription.
J S
JS
Hanas
D J
DJ
Hazuda
C W
CW
Wu
D000818:Animals; D004247:DNA / Q000378:metabolism*; D004277:DNA, Single-Stranded / Q000378:metabolism; D003850:Deoxyribonuclease I / Q000378:metabolism; D009691:Nucleic Acid Denaturation; D009695:Nucleic Acid Renaturation / Q000187:drug effects; D010206:Papain / Q000378:metabolism; D010446:Peptide Fragments / Q000502:physiology; D012313:RNA / Q000235:genetics; D013329:Structure-Activity Relationship; D015534:Trans-Activators; D014157:Transcription Factors / Q000494:pharmacology / Q000502:physiology*; D014158:Transcription, Genetic; D014357:Trypsin / Q000378:metabolism; D029867:Xenopus Proteins; D014982:Xenopus laevis; D015032:Zinc / Q000494:pharmacology
D004277:DNA, Single-Stranded; D010446:Peptide Fragments; C044544:TFAM protein, Xenopus; D015534:Trans-Activators; D014157:Transcription Factors; C097078:XL-MTTFA protein, Xenopus; D029867:Xenopus Proteins; D012313:RNA; D004247:DNA; D003850:Deoxyribonuclease I; D014357:Trypsin; D010206:Papain; D015032:Zinc