The Sin3p PAH Domains Provide Separate Functions Repressing Meiotic Gene Transcription in Saccharomyces cerevisiae

Department of Molecular Biology, University of Medicine and Dentistry of New Jersey, Two Medical Center Drive, Stratford, NJ 08084, USA.
Eukaryotic Cell (Impact Factor: 3.18). 10/2010; 9(12):1835-44. DOI: 10.1128/EC.00143-10
Source: PubMed


Meiotic genes in budding yeast are repressed during vegetative growth but are transiently induced during specific stages of
meiosis. Sin3p represses the early meiotic gene (EMG) by bridging the DNA binding protein Ume6p to the histone deacetylase
Rpd3p. Sin3p contains four paired amphipathic helix (PAH) domains, one of which (PAH3) is required for repressing several
genes expressed during mitotic cell division. This report examines the roles of the PAH domains in mediating EMG repression
during mitotic cell division and following meiotic induction. PAH2 and PAH3 are required for mitotic EMG repression, while
electrophoretic mobility shift assays indicate that only PAH2 is required for stable Ume6p-promoter interaction. Unlike mitotic
repression, reestablishing EMG repression following transient meiotic induction requires PAH3 and PAH4. In addition, the role
of Sin3p in reestablishing repression is expanded to include additional loci that it does not control during vegetative growth.
These findings indicate that mitotic and postinduction EMG repressions are mediated by two separate systems that utilize different
Sin3p domains.

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Available from: Randy Strich, Aug 25, 2014
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