title: Genome-wide function of H2B ubiquitylation in promoter and genic regions.
abstract: Nucleosomal organization in and around genes may contribute substantially to transcriptional regulation. The contribution of histone modifications to genome-wide nucleosomal organization has not been systematically evaluated. In the present study, we examine the role of H2BK123 ubiquitylation, a key regulator of several histone modifications, on nucleosomal organization at promoter, genic, and transcription termination regions in Saccharomyces cerevisiae. Using high-resolution MNase chromatin immunoprecipitation and sequencing (ChIP-seq), we map nucleosome positioning and occupancy in mutants of the H2BK123 ubiquitylation pathway. We found that H2B ubiquitylation-mediated nucleosome formation and/or stability inhibits the assembly of the transcription machinery at normally quiescent promoters, whereas ubiquitylation within highly active gene bodies promotes transcription elongation. This regulation does not proceed through ubiquitylation-regulated histone marks at H3K4, K36, and K79. Our findings suggest that mechanistically similar functions of H2B ubiquitylation (nucleosome assembly) elicit different functional outcomes on genes depending on its positional context in promoters (repressive) versus transcribed regions (activating).
authors: Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, USA.
authors: Kiran
authors: K
authors: Batta
authors: Zhenhai
authors: Z
authors: Zhang
authors: Kuangyu
authors: K
authors: Yen
authors: David B
authors: DB
authors: Goffman
authors: B Franklin
authors: BF
authors: Pugh
mesh_terms: D019175:DNA Methylation; D004257:DNA Polymerase II / Q000378:metabolism; D004271:DNA, Fungal / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D016681:Genome, Fungal; D006657:Histones / Q000235:genetics / Q000378:metabolism*; D009707:Nucleosomes / Q000378:metabolism; D011401:Promoter Regions, Genetic; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism; D054875:Ubiquitination
chemical_list: D004271:DNA, Fungal; D006657:Histones; D009707:Nucleosomes; D029701:Saccharomyces cerevisiae Proteins; D004257:DNA Polymerase II