title: Global analysis of functional surfaces of core histones with comprehensive point mutants.
abstract: The core histones are essential components of the nucleosome that act as global negative regulators of DNA-mediated reactions including transcription, DNA replication and DNA repair. Modified residues in the N-terminal tails are well characterized in transcription, but not in DNA replication and DNA repair. In addition, roles of residues in the core globular domains are not yet well characterized in any DNA-mediated reactions. To comprehensively understand the functional surface(s) of a core histone, we constructed 320 yeast mutant strains, each of which has a point mutation in a core histone, and identified 42 residues responsible for the suppressor of Ty (Spt(-)) phenotypes, and 8, 30 and 61 residues for sensitivities to 6-azauracil (6AU), hydroxyurea (HU) and methyl-methanesulfonate (MMS), respectively. In addition to residues that affect one specific assay, residues involved in multiple reactions were found, and surprisingly, about half of them were clustered at either the nucleosome entry site, the surface required for nucleosome-nucleosome interactions in crystal packing or their surroundings. This comprehensive mutation approach was proved to be powerful for identification of the functional surfaces of a core histone in a variety of DNA-mediated reactions and could be an effective strategy for characterizing other evolutionarily conserved hub-like factors for which surface structural information is available.
authors.affiliation: Laboratory of Developmental Biology, Institute of Molecular and Cellular Biosciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.
authors.forename: Kazuko
authors.initials: K
authors.lastname: Matsubara
authors.forename: Norihiko
authors.initials: N
authors.lastname: Sano
authors.forename: Takashi
authors.initials: T
authors.lastname: Umehara
authors.forename: Masami
authors.initials: M
authors.lastname: Horikoshi
mesh_terms: D000595:Amino Acid Sequence; D006657:Histones / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D006918:Hydroxyurea / Q000494:pharmacology; D008741:Methyl Methanesulfonate / Q000494:pharmacology; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009153:Mutagens / Q000494:pharmacology; D009707:Nucleosomes / Q000235:genetics / Q000378:metabolism; D010641:Phenotype; D017354:Point Mutation; D017434:Protein Structure, Tertiary; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism; D014498:Uracil / Q000031:analogs & derivatives / Q000494:pharmacology
chemical_list: D006657:Histones; D009153:Mutagens; D009707:Nucleosomes; D029701:Saccharomyces cerevisiae Proteins; D014498:Uracil; D008741:Methyl Methanesulfonate; C100248:azauracil; D006918:Hydroxyurea