Mapping of the sites of protection on a 5 S RNA gene by the Xenopus transcription factor IIIA. A model for the interaction.
The contact points of transcription factor IIIA with the internal control region of the 5 S RNA gene of Xenopus have been investigated by probing the accessibility of the DNA in the protein-DNA complex to dimethylsulphate and to micrococcal nuclease. The results of quantitative measurements, combined with those from earlier DNase I and DNase II protection studies, are consistent with a series of multiple contacts about five base-pairs apart, or half a double-helical turn, along the whole length of the internal control region. The nine patches of contact we have mapped could correspond to nine DNA-binding fingers in the protein. A model for the overall geometry of the interaction is presented in which the protein lies on one face of the DNA double helix.
D000818:Animals; D001665:Binding Sites; D002874:Chromosome Mapping; D005796:Genes; D046911:Macromolecular Substances; D008745:Methylation; D008836:Micrococcal Nuclease; D008954:Models, Biological; D012335:RNA, Ribosomal / Q000235:genetics*; D035582:Transcription Factor TFIIIA; D014157:Transcription Factors / Q000235:genetics*; D014981:Xenopus
D046911:Macromolecular Substances; D012335:RNA, Ribosomal; D035582:Transcription Factor TFIIIA; D014157:Transcription Factors; D008836:Micrococcal Nuclease