title: An analysis of transcription factor TFIIIA-mediated DNA supercoiling.
abstract: We have analyzed transcription factor-mediated DNA supercoiling catalyzed by the Xenopus oocyte extract (S-150). Under conditions that inhibit endogenous supercoiling activity (2 mM EDTA), the 5S RNA specific transcription factor, TFIIIA, promotes a negative change in DNA linking number. The SV40 binding protein, T antigen, appears not to promote DNA supercoiling under these conditions. A nucleosomal ladder can be seen after DNase I digestions only if the DNA template is pre-bound by TFIIIA prior to the addition of the S-150 extract. These studies suggest that TFIIIA may stimulate DNA supercoiling by enhancing the development of protein-DNA interactions via a mechanism that may include nucleosome assembly.
authors.affiliation: Fels Institute for Cancer Research and Molecular Biology, Temple University School of Medicine, Philadelphia, PA 19140.
authors.forename: J M
authors.initials: JM
authors.lastname: Sekiguchi
authors.forename: E B
authors.initials: EB
authors.lastname: Kmiec
mesh_terms: D000818:Animals; D000952:Antigens, Polyomavirus Transforming / Q000378:metabolism; D001345:Autoradiography; D002413:Cations, Divalent; D002875:Chromosomes; D004278:DNA, Superhelical / Q000378:metabolism*; D004587:Electrophoresis, Agar Gel; D010957:Plasmids; D035582:Transcription Factor TFIIIA; D014157:Transcription Factors / Q000378:metabolism*; D014981:Xenopus
chemical_list: D000952:Antigens, Polyomavirus Transforming; D002413:Cations, Divalent; D004278:DNA, Superhelical; D035582:Transcription Factor TFIIIA; D014157:Transcription Factors