Dynamics of Nucleosome Assembly in Solution Revealed by X-ray and Neutron Scattering

2015 Fiscal Year Final Research Report

• Project/Area Number: 25291037
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Biophysics
• Research Institution: Yokohama City University
• Principal Investigator: Sato Mamoru 横浜市立大学, 生命医科学研究科, 教授 (60170784)
• Co-Investigator(Kenkyū-buntansha): ODA Takashi 横浜市立大学, 大学院生命医科学研究科, 特任助教 (00573164)
• Co-Investigator(Renkei-kenkyūsha): KURUMIZAKA Hitoshi 早稲田大学, 大学院先進理工学研究科, 教授 (80300870)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: 溶液散乱 / 小角散乱 / クロマチン / ヌクレオソーム / セントロメア / 分子動力学計算 / 粗視化モデル

Outline of Final Research Achievements

Solution X-ray and neutron scattering analyses have showed that both ends of double stranded DNA in H2A.B nucleosome are peeled off from the histone octamer and is exposed to the solvent. This facilitates the chromatin takes a looser conformation than H2A nucleosome. Also, solution X-ray scattering analysis indicates that conformation of higher-order nucleosome complex, H3-(CENP-A)-H3 tri-nucleosome is more opened than that of H3-H3-H3 tri-nucleosome. Furthermore, MD-SAXS analysis (solution X-ray scattering analysis combined with molecular dynamics calculation) using a coarse grained model as a tri-nucleosome has analyzed the dynamical structure of the chromatin in centromere and non-centromere regions at atomic resolution and elucidated the functional significance of the chromatin containing CENP-A nucleosome in the centromere.

Free Research Field

生物物理学