title: Rap1p and other transcriptional regulators can function in defining distinct domains of gene expression.
abstract: Barrier elements that are able to block the propagation of transcriptional silencing in yeast are functionally similar to chromatin boundary/insulator elements in metazoans that delimit functional chromosomal domains. We show that the upstream activating sequences of many highly expressed ribosome protein genes and glycolytic genes exhibit barrier activity. Analyses of these barriers indicate that binding sites for transcriptional regulators Rap1p, Abf1p, Reb1p, Adr1p and Gcn4p may participate in barrier function. We also present evidence suggesting that Rap1p is directly involved in barrier activity, and its barrier function correlates with local changes in chromatin structure. We further demonstrate that tethering the transcriptional activation domain of Rap1p to DNA is sufficient to recapitulate barrier activity. Moreover, targeting the activation domain of Adr1p or Gcn4p also establishes a barrier to silencing. These results support the notion that transcriptional regulators could also participate in delimiting functional domains in the genome.
authors.affiliation: Department of Biochemistry, University of Nebraska-Lincoln, Lincoln, NE 68588, USA.
authors.forename: Qun
authors.initials: Q
authors.lastname: Yu
authors.forename: Runxiang
authors.initials: R
authors.lastname: Qiu
authors.forename: Travis B
authors.initials: TB
authors.lastname: Foland
authors.forename: Dan
authors.initials: D
authors.lastname: Griesen
authors.forename: Carl S
authors.initials: CS
authors.lastname: Galloway
authors.forename: Ya-Hui
authors.initials: YH
authors.lastname: Chiu
authors.forename: Joseph
authors.initials: J
authors.lastname: Sandmeier
authors.forename: James R
authors.initials: JR
authors.lastname: Broach
authors.forename: Xin
authors.initials: X
authors.lastname: Bi
mesh_terms: D001665:Binding Sites / Q000235:genetics; D002843:Chromatin / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics; D015966:Gene Expression Regulation, Fungal; D020868:Gene Silencing; D009154:Mutation; D020648:Peptide Elongation Factor 1 / Q000235:genetics; D011494:Protein Kinases / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D000089804:Shelterin Complex; D034501:Telomere-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic
chemical_list: C074682:ADR1 protein, S cerevisiae; D002843:Chromatin; D004268:DNA-Binding Proteins; D020648:Peptide Elongation Factor 1; C440829:RAP1 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D000089804:Shelterin Complex; D034501:Telomere-Binding Proteins; D014157:Transcription Factors; D011494:Protein Kinases