Interaction between nuclear lamina and heterochromatin during G1 phase

Research Project

Project/Area Number	18K06066
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Review Section	Basic Section 43010:Molecular biology-related
Research Institution	University of Hyogo
Principal Investigator	Hirose Fumiko 兵庫県立大学, 理学研究科, 准教授 (60208882)
Project Period (FY)	2018-04-01 – 2023-03-31
Project Status	Completed (Fiscal Year 2022)
Budget Amount *help	¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000) Fiscal Year 2020: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000) Fiscal Year 2019: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000) Fiscal Year 2018: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
Keywords	核ラミナ / ヘテロクロマチン / 細胞周期 / ライブイメージング / G1期 / Ｇ１－Ｍ期 / Ｇ１期
Outline of Final Research Achievements	When animal cells enter mitosis, the nuclear envelope collapses and chromatin condenses into mitotic chromosomes, and the nuclear envelope is reconstituted around the chromosomes at the end of mitosis. It has been suggested that the network structure of the nuclear lamina, which exists just below the nuclear membrane, is involved in the arrangement of non-transcribed heterochromatin near the nuclear membrane, but the underlying molecular mechanism remains unclear. In this study, the interaction between lamin A, the major component of nuclear lamina and the heterochromatin-binding protein HP1β begins to interact on telophase chromosomes, and the interaction observed in living cells dynamically moves from the interior to the periphery of the nucleus in the early G1 phase. These results suggest that nuclear lamina formation is involved in the arrangement of heterochromatin to the nuclear periphery.
Academic Significance and Societal Importance of the Research Achievements	動物細胞は細胞分裂期に入ると、核膜の崩壊とクロマチンの染色体への凝縮が起こり、分裂期の最後には核膜が染色体の周囲で再構築される。この染色体テリトリーは細胞周期ごとにリセットされると言える。転写が起こらないヘテロクロマチンの核膜付近への配置には、核膜直下に存在する網目構造の核ラミナが関与していることが示唆されていたが、本研究の結果から、核ラミナの構成因子であるラミンAとヘテロクロマチン結合因子HP1βの細胞周期特異的な細胞分裂後の細胞でのヘテロクロマチンの核膜周縁への配置に重要な役割を果たしていることを示唆できた。