title: Torsional stress induces an S1 nuclease-hypersensitive site within the promoter of the Xenopus laevis oocyte-type 5S RNA gene.
abstract: The internal promoter of the Xenopus laevis oocyte-type 5S RNA gene is preferentially cleaved by S1 and Bal-31 nucleases in plasmid DNA. S1 nuclease sensitivity is largely dependent on supercoiling; however, Bal-31 cleaves within the 5S RNA gene in linear as well as in supercoiled DNA. The S1 nuclease-hypersensitive site is centered at position +48-52 of the gene at the 5' boundary of the promoter. A DNAase I-hypersensitive site is induced at this position upon binding of the transcription factor, TFIIIA, specific for the 5S RNA gene. The somatic-type 5S RNA gene promoter is not preferentially cleaved by S1 nuclease or Bal-31 nuclease in supercoiled DNA, nor does TFIIIA induce a DNase I site at position +50. This differential promoter response may be related to a 4-fold difference in TFIIIA affinity between the oocyte and somatic 5S RNA genes.
authors.forename: W F
authors.initials: WF
authors.lastname: Reynolds
authors.forename: J M
authors.initials: JM
authors.lastname: Gottesfeld
mesh_terms: D000818:Animals; D002874:Chromosome Mapping; D004278:DNA, Superhelical / Q000235:genetics*; D004720:Endonucleases; D005260:Female; D005786:Gene Expression Regulation; D005796:Genes; D009690:Nucleic Acid Conformation; D009865:Oocytes; D010957:Plasmids; D011401:Promoter Regions, Genetic; D012335:RNA, Ribosomal / Q000235:genetics*; D015719:Single-Strand Specific DNA and RNA Endonucleases; D014157:Transcription Factors / Q000378:metabolism; D014982:Xenopus laevis / Q000235:genetics*
chemical_list: D004278:DNA, Superhelical; D012335:RNA, Ribosomal; D014157:Transcription Factors; D004720:Endonucleases; D015719:Single-Strand Specific DNA and RNA Endonucleases