The Saccharomyces cerevisiae SIN3 gene, a negative regulator of HO, contains four paired amphipathic helix motifs.

Abstract

(14) with eight pools of a YCp50-based genomic library (kindly supplied by M. Rose). Because the sin3-1 mutation suppresses the requirement of the HO:lacZ promoter for SWI5, the parent strain will have high levels of ,-galactosidase activity relative to the activity of a similar strain bearing a functional copy of SIN3. A total of 104 Ura+ transformants were selected on SD-uracil plates and screened for 3-galactosidase production on SD-uracil plates containing 50 mM KPi (pH 7.0) and 600 ,ug of 5-bromo-4-chloro-3-indolyl-,-D-galactoside (X-Gal) per ml. White colonies were selected and counterscreened for a-factor production by a halo assay (10). Plasmid DNA was prepared from transformants that could produce a-factor, and the transformants were tested for the ability to complement sin3-1 when reintroduced into strain S596-3D. One

Ume1p Represses Meiotic Gene Transcription in Saccharomyces cerevisiae through Interaction with the Histone Deacetylase Rpd3p

“…The rapid induction of UME1 co-incident with the down-regulation of SPO13 suggests a role for this factor in the establishment, as well as the maintenance, of full transcriptional repression of SPO13. These results indicate that, unlike other UME factors studies (7,8,15,35), UME1 is transcriptionally regulated. However, placing UME1 on a high-copy plasmid did not alter the transcription kinetics of SPO13 during meiosis or in return-to-growth assays (data not shown).…”

Histone deacetylase associated with mSin3A mediates repression by the acute promyelocytic leukemia-associated PLZF protein

“…The Sin3 proteins contain four paired amphipathic helices (PAH 1 ± 4 ) which are likely to mediate protein ± protein interactions (Wang et al, 1990). The yeast twohybrid system was used to map the speci®c domain of mSin3A that interacts with PLZF.…”

The impact of differential binding of wild-type RARα, PML-, PLZF- and NPM-RARα fusion proteins towards transcriptional co-activator, RIP-140, on retinoic acid responses in acute promyelocytic leukemia

“…[11][12][13][14][15][16][17] Using gel shift assays, we show that NPM-, PMLand PLZF-RAR homodimers would also associate with SMRT, but with different binding affinity as compared with the wildtype RAR/RXR heterodimer ( Figure 3). A SMRT retardation band could be seen when 0.3 g GST-SMRT fusion protein was added to these APL fusion homodimers (Figure 3, lane 12, 20 and 28).…”

“…10 RARs can dimerize with retinoid X receptors (RXRs) to bind to retinoic acid response elements (RAREs) located in promoter/enhancer regions of specific genes. In the absence of ligand (RA), RAR/RXR heterodimers will associate with transcriptional co-repressors (SMRT/N-CoR), [11][12][13] which recruit transcriptional repressors, Sin3 [14][15][16] and histone deacetylase. 17 This renders the nearby chromatin inaccessible to transcriptional activators (SRC-1, RIP-140), and result in repression of basal transcription.…”