title: Mutations in both the structured domain and N-terminus of histone H2B bypass the requirement for Swi-Snf in yeast.
abstract: The chromatin elements targeted by the ATPdependent, Swi-Snf nucleosome-remodeling complex are unknown. To address this question, we generated mutations in yeast histone H2B that suppress phenotypes associated with the absence of Swi-Snf. Sin- (Swi-Snf-independent) mutations occur in residues involved in H2A-H2B dimer formation, dimer- tetramer association, and in the H2B N-terminus. The strongest and most pleiotropic Sin- mutation removed 20 amino acid residues from the H2B N-terminus. This mutation allowed active chromatin to be formed at the SUC2 locus in a snf5Delta mutant and resulted in hyperactivated levels of SUC2 mRNA under inducing conditions. Thus, the H2B N-terminus may be an important target of Swi-Snf in vivo. The GCN5 gene product, the catalytic subunit of several nuclear histone acetytransferase complexes that modify histone N-termini, was also found to act in conjunction with Swi-Snf. The phenotypes of double gcn5Deltasnf5Delta mutants suggest that histone acetylation may play both positive and negative roles in the activity of the Swi-Snf-remodeling factor.
authors.affiliation: Program in Molecular Biology, Sloan Kettering Cancer Center and Cornell University Graduate School of Medical Sciences, New York, NY 10021, USA.
authors.forename: J
authors.initials: J
authors.lastname: Recht
authors.forename: M A
authors.initials: MA
authors.lastname: Osley
mesh_terms: D000595:Amino Acid Sequence; D002843:Chromatin / Q000235:genetics / Q000378:metabolism; D002868:Chromosomal Proteins, Non-Histone; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D019281:Dimerization; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D005800:Genes, Fungal; D006026:Glycoside Hydrolases / Q000235:genetics / Q000378:metabolism; D051548:Histone Acetyltransferases; D006657:Histones / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D009707:Nucleosomes / Q000235:genetics / Q000378:metabolism; D010641:Phenotype; D011487:Protein Conformation; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism; D017433:Protein Structure, Secondary; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D043324:beta-Fructofuranosidase; D000099224:p300-CBP-Associated Factor
chemical_list: D002843:Chromatin; D002868:Chromosomal Proteins, Non-Histone; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; D006026:Glycoside Hydrolases; D051548:Histone Acetyltransferases; D006657:Histones; D009707:Nucleosomes; D011494:Protein Kinases; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D043324:beta-Fructofuranosidase; C066190:SNF5 protein, S cerevisiae; C501392:GCN5 protein, S cerevisiae; D000099224:p300-CBP-Associated Factor