Sin3 is involved in cell size control at Start in Saccharomyces cerevisiae.
Saccharomyces cerevisiae cells control their cell size at a point in late G(1) called Start. Here, we describe a negative role for the Sin3/Rpd3 histone deacetylase complex in the regulation of cell size at Start. Initiation of G(1)/S-specific transcription of CLN1, CLN2 and PCL1 in a sin3Delta strain occurs at a reduced cell size compared with a wild-type strain. In addition, inactivation of the transcriptional regulator SIN3 partially suppressed a cln3Delta mutant, causing sin3Deltacln3Delta double mutants to start the cell cycle at wild-type size. Chromatin immunoprecipitation results demonstrate that Sin3 and Rpd3 are recruited to promoters of SBF (Swi4/Swi6)-regulated genes, and reveal that binding of Sin3 to SBF-specific promoters is cell-cycle regulated. We observe that transcriptional repression of SBF-dependent genes in early G(1) coincides with the recruitment of Sin3 to specific promoters, whereas binding of Sin3 is abolished from Swi4/Swi6-regulated promoters when transcription is activated at the G(1) to S phase transition. We conclude that the Sin3/Rpd3 histone deacetylase complex helps to prevent premature activation of the S phase in daughter cells.
Stephan
Octavian
O
Department of Biology, Friedrich-Alexander-University Erlangen-Nürnberg, Germany.
Koch
Christian
C
D016213:Cyclins / Q000235:genetics / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D016193:G1 Phase; D015966:Gene Expression Regulation, Fungal; D006655:Histone Deacetylases / Q000235:genetics / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000166:cytology* / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic
C079895:CLN3 protein, S cerevisiae; D016213:Cyclins; D004268:DNA-Binding Proteins; D012097:Repressor Proteins; C071731:SIN3 protein, S cerevisiae; C062214:SWI4 protein, S cerevisiae; C075111:SWI6 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; C071665:RPD3 protein, S cerevisiae; D006655:Histone Deacetylases