title: A role for H2B ubiquitylation in DNA replication.
abstract: The monoubiquitylation of histone H2B plays an important role in gene expression by contributing to the regulation of transcription elongation and mRNA processing and export. We explored additional cellular functions of this histone modification by investigating its localization to intergenic regions. H2B ubiquitylation is present in chromatin around origins of DNA replication in budding yeast, and as DNA is replicated its levels are maintained on daughter strands by the Bre1 ubiquitin ligase. In the absence of H2B ubiquitylation, the prereplication complex is formed and activated, but replication fork progression is slowed down and the replisome becomes unstable in the presence of hydroxyurea. H2B ubiquitylation promotes the assembly or stability of nucleosomes on newly replicated DNA, and this function is postulated to contribute to fork progression and replisome stability.
authors.affiliation: Molecular Genetics and Microbiology, University of New Mexico School of Medicine, Albuquerque, NM 87131, USA.
authors.forename: Kelly M
authors.initials: KM
authors.lastname: Trujillo
authors.forename: Mary Ann
authors.initials: MA
authors.lastname: Osley
mesh_terms: D001665:Binding Sites; D018797:Cell Cycle Proteins / Q000378:metabolism; D064447:Checkpoint Kinase 2; D004261:DNA Replication / Q000187:drug effects; D004271:DNA, Fungal / Q000096:biosynthesis* / Q000187:drug effects; D021901:DNA, Intergenic; D015966:Gene Expression Regulation, Fungal; D006657:Histones / Q000235:genetics / Q000378:metabolism*; D006918:Hydroxyurea / Q000494:pharmacology; D019384:Nucleic Acid Synthesis Inhibitors / Q000494:pharmacology; D009707:Nucleosomes / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D013997:Time Factors; D054875:Ubiquitination
chemical_list: C472168:Bre1 protein, S cerevisiae; D018797:Cell Cycle Proteins; D004271:DNA, Fungal; D021901:DNA, Intergenic; D006657:Histones; D019384:Nucleic Acid Synthesis Inhibitors; D009707:Nucleosomes; D029701:Saccharomyces cerevisiae Proteins; D064447:Checkpoint Kinase 2; C090464:Bub1 spindle checkpoint protein; D017346:Protein Serine-Threonine Kinases; C067022:RAD53 protein, S cerevisiae; D006918:Hydroxyurea