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. 1996 May 1;15(9):2184-95.

Cooperation at a distance between silencers and proto-silencers at the yeast HML locus

C Boscheron  1 , L Maillet, S Marcand, M Tsai-Pflugfelder, S M Gasser, E Gilson
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Cooperation at a distance between silencers and proto-silencers at the yeast HML locus

C Boscheron et al. EMBO J. .

Abstract

Transcriptional repression at the silent yeast mating type loci is achieved through the formation of a particular nucleoprotein complex at specific cis-acting elements called silencers. This complex in turn appears to initiate the spreading of a histone binding protein complex into the surrounding chromatin, which restricts accessibility of the region to the transcription machinery. We have investigated long-range, cooperative effects between silencers by studying the repression of a reporter gene integrated at the HML locus flanked by various combinations of wild-type and mutated silencer sequences. Two silencers can cooperate over >4000 bp to repress transcription efficiently. More importantly, a single binding site for either the repressor activator protein 1 (Rap1), the autonomous replicating sequence (ARS) binding factor 1 (Abf1) or the origin recognition complex (ORC) can enhance the action of a distant silencer without acting as a silencer on its own. Functional cooperativity is demonstrated using a quantitative assay for repression, and varies with the affinity of the binding sites used. Since the repression mechanism is Sir dependent, the Rap1, ORC and/or Abf1 proteins bound to distant DNA elements may interact to create an interface of sufficiently high affinity such that Sir-containing complexes bind, nucleating the silent chromatin state.

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References

    1. Mol Cell Biol. 1991 Nov;11(11):5648-59 - PubMed
    1. Mol Cell Biol. 1995 Jul;15(7):3496-506 - PubMed
    1. J Mol Biol. 1984 Oct 5;178(4):815-34 - PubMed
    1. Mol Cell Biol. 1991 Apr;11(4):2253-62 - PubMed
    1. Genes Dev. 1993 Jul;7(7A):1133-45 - PubMed

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