Fission yeast Tup1-like repressors repress chromatin remodeling at the fbp1+ promoter and the ade6-M26 recombination hotspot.
Chromatin remodeling plays crucial roles in the regulation of gene expression and recombination. Transcription of the fission yeast fbp1(+) gene and recombination at the meiotic recombination hotspot ade6-M26 (M26) are both regulated by cAMP responsive element (CRE)-like sequences and the CREB/ATF-type transcription factor Atf1*Pcr1. The Tup11 and Tup12 proteins, the fission yeast counterparts of the Saccharomyces cerevisiae Tup1 corepressor, are involved in glucose repression of the fbp1(+) transcription. We have analyzed roles of the Tup1-like corepressors in chromatin regulation around the fbp1(+) promoter and the M26 hotspot. We found that the chromatin structure around two regulatory elements for fbp1(+) was remodeled under derepressed conditions in concert with the robust activation of fbp1(+) transcription. Strains with tup11delta tup12delta double deletions grown in repressed conditions exhibited the chromatin state associated with wild-type cells grown in derepressed conditions. Interestingly, deletion of rst2(+), encoding a transcription factor controlled by the cAMP-dependent kinase, alleviated the tup11delta tup12delta defects in chromatin regulation but not in transcription repression. The chromatin at the M26 site in mitotic cultures of a tup11delta tup12delta mutant resembled that of wild-type meiotic cells. These observations suggest that these fission yeast Tup1-like corepressors repress chromatin remodeling at CRE-related sequences and that Rst2 antagonizes this function.
Genetic Dynamics Research Unit-Laboratory, The Institute of Physical and Chemical Research (RIKEN), Wako-shi, Saitama 351-0198, Japan. kohta@postman.riken.go.jp
Kouji
K
Hirota
Charles S
CS
Hoffman
Takehiko
T
Shibata
Kunihiro
K
Ohta
D002843:Chromatin / Q000502:physiology; D042002:Chromatin Assembly and Disassembly / Q000502:physiology*; D006597:Fructose-Bisphosphatase; D008540:Meiosis / Q000235:genetics / Q000502:physiology; D011401:Promoter Regions, Genetic; D011995:Recombination, Genetic / Q000502:physiology*; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics*; D012568:Schizosaccharomyces / Q000235:genetics / Q000378:metabolism; D029702:Schizosaccharomyces pombe Proteins / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism
D002843:Chromatin; C415971:RST2 protein, S pombe; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins; D029702:Schizosaccharomyces pombe Proteins; C471690:TUP1 protein, S pombe; D014157:Transcription Factors; C471691:Tup11 protein, S pombe; C471692:Tup12 protein, S pombe; C111172:FBP1 protein, S cerevisiae; D006597:Fructose-Bisphosphatase