title: Chromosome Scaffold is a Double-Stranded Assembly of Scaffold Proteins.
abstract: Chromosome higher order structure has been an enigma for over a century. The most important structural finding has been the presence of a chromosome scaffold composed of non-histone proteins; so-called scaffold proteins. However, the organization and function of the scaffold are still controversial. Here, we use three dimensional-structured illumination microscopy (3D-SIM) and focused ion beam/scanning electron microscopy (FIB/SEM) to reveal the axial distributions of scaffold proteins in metaphase chromosomes comprising two strands. We also find that scaffold protein can adaptably recover its original localization after chromosome reversion in the presence of cations. This reversion to the original morphology underscores the role of the scaffold for intrinsic structural integrity of chromosomes. We therefore propose a new structural model of the chromosome scaffold that includes twisted double strands, consistent with the physical properties of chromosomal bending flexibility and rigidity. Our model provides new insights into chromosome higher order structure.
authors.affiliation: Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, JAPAN.
authors.forename: Rawin
authors.initials: R
authors.lastname: Poonperm
authors.affiliation: Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, JAPAN.|Frontier Research Base for Global Young Researchers, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, JAPAN.
authors.forename: Hideaki
authors.initials: H
authors.lastname: Takata
authors.affiliation: Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, JAPAN.
authors.forename: Tohru
authors.initials: T
authors.lastname: Hamano
authors.affiliation: Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka 565-0871, JAPAN.|Advanced ICT Research Institute Kobe, National Institute of Information and Communications Technology, 588-2 Iwaoka, Iwaoka-cho, Nishi-ku, Kobe 651-2492, JAPAN.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Matsuda
authors.affiliation: Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, JAPAN.
authors.forename: Susumu
authors.initials: S
authors.lastname: Uchiyama
authors.affiliation: Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka 565-0871, JAPAN.|Advanced ICT Research Institute Kobe, National Institute of Information and Communications Technology, 588-2 Iwaoka, Iwaoka-cho, Nishi-ku, Kobe 651-2492, JAPAN.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Hiraoka
authors.affiliation: Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, JAPAN.
authors.forename: Kiichi
authors.initials: K
authors.lastname: Fukui
mesh_terms: D000251:Adenosine Triphosphatases / Q000502:physiology / Q000648:ultrastructure; D000951:Antigens, Neoplasm / Q000502:physiology / Q000648:ultrastructure; D002868:Chromosomal Proteins, Non-Histone / Q000502:physiology / Q000648:ultrastructure*; D002877:Chromosomes, Human / Q000502:physiology / Q000648:ultrastructure*; D004250:DNA Topoisomerases, Type II / Q000502:physiology / Q000648:ultrastructure; D004268:DNA-Binding Proteins / Q000502:physiology / Q000648:ultrastructure; D006367:HeLa Cells; D006801:Humans; D021621:Imaging, Three-Dimensional; D016547:Kinesins / Q000502:physiology / Q000648:ultrastructure; D008677:Metaphase; D046912:Multiprotein Complexes / Q000502:physiology / Q000648:ultrastructure
chemical_list: D000951:Antigens, Neoplasm; D002868:Chromosomal Proteins, Non-Histone; D004268:DNA-Binding Proteins; D046912:Multiprotein Complexes; C108312:condensin complexes; D000251:Adenosine Triphosphatases; C484228:KIF4A protein, human; D016547:Kinesins; D004250:DNA Topoisomerases, Type II