2. Academic Validation
  3. Structural basis of a nucleosome containing histone H2A.B/H2A.Bbd that transiently associates with reorganized chromatin

Structural basis of a nucleosome containing histone H2A.B/H2A.Bbd that transiently associates with reorganized chromatin

  • Sci Rep. 2013 Dec 16;3:3510. doi: 10.1038/srep03510.
Yasuhiro Arimura 1,  Hiroshi Kimura 2,  Takashi Oda 3,  Koichi Sato 1,  Akihisa Osakabe 1,  Hiroaki Tachiwana 1,  Yuko Sato 2,  Yasuha Kinugasa 4,  Tsuyoshi Ikura 5,  Masaaki Sugiyama 6,  Mamoru Sato 7,  Hitoshi Kurumizaka 1
Affiliations

Affiliations

  • 1 Laboratory of Structural Biology, Graduate School of Advanced Science and Engineering, Waseda University, 2-2 wakamatsu-cho, Shinjuku-ku, Tokyo 162-8480, Japan.
  • 2 1] Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka 565-0871, Japan [2] JST, CREST, 1-3 Yamadaoka, Suita, Osaka, 565-0871, Japan.
  • 3 Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi, Yokohama 230-0045, Japan.
  • 4 Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka 565-0871, Japan.
  • 5 Department of Mutagenesis, Division of Chromatin Regulatory Network, Radiation Biology Center, Kyoto University, Yoshidakonoe, Sakyo-ku, Kyoto 606-8501, Japan.
  • 6 Research Reactor Institute, Kyoto University, Kumatori, Osaka, 590-0494, Japan.
  • 7 1] Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi, Yokohama 230-0045, Japan [2] RIKEN SPring-8 Center, 1-1-1 koto, Sayo, Hyogo 679-5148, Japan.
PMID: 24336483 DOI: 10.1038/srep03510
Abstract

Human histone H2A.B (formerly H2A.Bbd), a non-allelic H2A variant, exchanges rapidly as compared to canonical H2A, and preferentially associates with actively transcribed genes. We found that H2A.B transiently accumulated at DNA replication and repair foci in living cells. To explore the biochemical function of H2A.B, we performed nucleosome reconstitution analyses using various lengths of DNA. Two types of H2A.B nucleosomes, octasome and hexasome, were formed with 116, 124, or 130 base pairs (bp) of DNA, and only the octasome was formed with 136 or 146 bp DNA. In contrast, only hexasome formation was observed by canonical H2A with 116 or 124 bp DNA. A small-angle X-ray scattering analysis revealed that the H2A.B octasome is more extended, due to the flexible detachment of the DNA regions at the entry/exit sites from the histone surface. These results suggested that H2A.B rapidly and transiently forms nucleosomes with short DNA segments during chromatin reorganization.

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