title: Histone chaperone-mediated nucleosome assembly process.
abstract: A huge amount of information is stored in genomic DNA and this stored information resides inside the nucleus with the aid of chromosomal condensation factors. It has been reported that the repeat nucleosome core particle (NCP) consists of 147-bp of DNA and two copies of H2A, H2B, H3 and H4. Regulation of chromosomal structure is important to many processes inside the cell. In vivo, a group of histone chaperones facilitate and regulate nucleosome assembly. How NCPs are constructed with the aid of histone chaperones remains unclear. In this study, the histone chaperone-mediated nucleosome assembly process was investigated using single-molecule tethered particle motion (TPM) experiments. It was found that Asf1 is able to exert more influence than Nap1 and poly glutamate acid (PGA) on the nucleosome formation process, which highlights Asf1's specific role in tetrasome formation. Thermodynamic parameters supported a model whereby energetically favored nucleosomal complexes compete with non-nucleosomal complexes. In addition, our kinetic findings propose the model that histone chaperones mediate nucleosome assembly along a path that leads to enthalpy-favored products with free histones as reaction substrates.
authors.affiliation: Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan; Biophotonics interdisciplinary research center, National Yang-Ming University, 112, Taipei, Taiwan.
authors.forename: Hsiu-Fang
authors.initials: HF
authors.lastname: Fan
authors.affiliation: Department of Biotechnology and Laboratory Science in Medicine, National Yang-Ming University, 112, Taipei, Taiwan.
authors.forename: Zi-Ning
authors.initials: ZN
authors.lastname: Liu
authors.affiliation: Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Sih-Yao
authors.initials: SY
authors.lastname: Chow
authors.affiliation: Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan.
authors.forename: Yi-Han
authors.initials: YH
authors.lastname: Lu
authors.affiliation: Department of Biotechnology and Laboratory Science in Medicine, National Yang-Ming University, 112, Taipei, Taiwan.
authors.forename: Hsin
authors.initials: H
authors.lastname: Li
mesh_terms: D018797:Cell Cycle Proteins / Q000737:chemistry / Q000378:metabolism*; D018832:Molecular Chaperones / Q000737:chemistry / Q000378:metabolism*; D056490:Nucleosome Assembly Protein 1 / Q000737:chemistry / Q000378:metabolism*; D009707:Nucleosomes / Q000737:chemistry / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000378:metabolism*
chemical_list: C109731:ASF1 protein, S cerevisiae; D018797:Cell Cycle Proteins; D018832:Molecular Chaperones; C533556:NAP1 protein, S cerevisiae; D056490:Nucleosome Assembly Protein 1; D009707:Nucleosomes; D029701:Saccharomyces cerevisiae Proteins