Rap1p and other transcriptional regulators can function in defining distinct domains of gene expression.
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.
Yu
Qun
Q
Department of Biochemistry, University of Nebraska-Lincoln, Lincoln, NE 68588, USA.
Qiu
Runxiang
R
Foland
Travis B
TB
Griesen
Dan
D
Galloway
Carl S
CS
Chiu
Ya-Hui
YH
Sandmeier
Joseph
J
Broach
James R
JR
Bi
Xin
X
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
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