The yeast SWI-SNF complex facilitates binding of a transcriptional activator to nucleosomal sites in vivo
UMass Chan AffiliationsProgram in Molecular Medicine
Department of Biochemistry and Molecular Biology
Document TypeJournal Article
Chromosomal Proteins, Non-Histone
Gene Expression Regulation, Fungal
Promoter Regions (Genetics)
*Saccharomyces cerevisiae Proteins
Medicine and Health Sciences
MetadataShow full item record
AbstractThe Saccharomyces cerevisiae SWI-SNF complex is a 2-MDa protein assembly that is required for the function of many transcriptional activators. Here we describe experiments on the role of the SWI-SNF complex in activation of transcription by the yeast activator GAL4. We find that while SWI-SNF activity is not required for the GAL4 activator to bind to and activate transcription from nucleosome-free binding sites, the complex is required for GAL4 to bind to and function at low-affinity, nucleosomal binding sites in vivo. This SWI-SNF dependence can be overcome by (i) replacing the low-affinity sites with higher-affinity, consensus GAL4 binding sequences or (ii) placing the low-affinity sites into a nucleosome-free region. These results define the criteria for the SWI-SNF dependence of gene expression and provide the first in vivo evidence that the SWI-SNF complex can regulate gene expression by modulating the DNA binding of an upstream activator protein.
SourceMol Cell Biol. 1997 Aug;17(8):4811-9.
Permanent Link to this Itemhttp://hdl.handle.net/20.500.14038/38583
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