Saccharomyces cerevisiae Yta7 regulates histone gene expression.

Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA.
Genetics (Impact Factor: 4.87). 06/2008; 179(1):291-304. DOI: 10.1534/genetics.107.086520
Source: PubMed

ABSTRACT The Saccharomyces cerevisiae Yta7 protein is a component of a nucleosome bound protein complex that maintains distinct transcriptional zones of chromatin. We previously found that one protein copurifying with Yta7 is the yFACT member Spt16. Epistasis analyses revealed a link between Yta7, Spt16, and other previously identified members of the histone regulatory pathway. In concurrence, Yta7 was found to regulate histone gene transcription in a cell-cycle-dependent manner. Association at the histone gene loci appeared to occur through binding of the bromodomain-like region of Yta7 with the N-terminal tail of histone H3. Our work suggests a mechanism in which Yta7 is localized to chromatin to establish regions of transcriptional silencing, and that one facet of this cellular mechanism is to modulate transcription of histone genes.

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