title: Chz1, a nuclear chaperone for histone H2AZ.
abstract: The histone variant H2AZ marks nucleosomes flanking the promoters of most genes of budding yeast. The incorporation of H2AZ into chromatin is dependent on the SWR1 complex, which catalyses the replacement of conventional histone H2A with H2AZ. In cells, the pool of unincorporated histone H2AZ has previously been found in association with Nap1, a chaperone for conventional histone H2A-H2B. Here, we report the discovery of Chz1, a histone chaperone that has preference for H2AZ and can also deliver a source of the histone variant for SWR1-dependent histone replacement. Bacterially expressed Chz1 forms a heterotrimer with H2AZ-H2B, stabilizing the association of the histone dimer. We have identified a conserved motif important for histone variant recognition within the H2AZ-interacting domain of Chz1. The presence of this motif in other metazoan proteins suggests that H2AZ-specific chaperones may be widely conserved.
authors.affiliation: Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA. luked@mail.nih.gov
authors.forename: Ed
authors.initials: E
authors.lastname: Luk
authors.forename: Ngoc-Diep
authors.initials: ND
authors.lastname: Vu
authors.forename: Kem
authors.initials: K
authors.lastname: Patteson
authors.forename: Gaku
authors.initials: G
authors.lastname: Mizuguchi
authors.forename: Wei-Hua
authors.initials: WH
authors.lastname: Wu
authors.forename: Anand
authors.initials: A
authors.lastname: Ranjan
authors.forename: Jonathon
authors.initials: J
authors.lastname: Backus
authors.forename: Subhojit
authors.initials: S
authors.lastname: Sen
authors.forename: Marc
authors.initials: M
authors.lastname: Lewis
authors.forename: Yawen
authors.initials: Y
authors.lastname: Bai
authors.forename: Carl
authors.initials: C
authors.lastname: Wu
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D000595:Amino Acid Sequence; D002352:Carrier Proteins / Q000737:chemistry; D018797:Cell Cycle Proteins / Q000502:physiology; D017124:Conserved Sequence; D019281:Dimerization; D056488:Histone Chaperones; D006657:Histones / Q000378:metabolism*; D006801:Humans; D018832:Molecular Chaperones / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000502:physiology; D056490:Nucleosome Assembly Protein 1; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D016415:Sequence Alignment
chemical_list: D002352:Carrier Proteins; D018797:Cell Cycle Proteins; C518297:Chz1 protein, S cerevisiae; C518298:HIRIP3 protein, human; D056488:Histone Chaperones; D006657:Histones; C493530:Htz1 protein, S cerevisiae; D018832:Molecular Chaperones; C533556:NAP1 protein, S cerevisiae; C533557:NAP1L1 protein, human; D009687:Nuclear Proteins; D056490:Nucleosome Assembly Protein 1; D029701:Saccharomyces cerevisiae Proteins; D000251:Adenosine Triphosphatases; C481261:Swr1 protein, S cerevisiae