プレ-rRNAの空間分布と核の機能的組織

Yu-Hang Pan¹, Lin Shan¹, Yu-Yao Zhang²

¹State Key Laboratory of RNA Innovation, Science and Engineering, New Cornerstone Science Laboratory, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Shanghai, China.

Nature

|July 23, 2025

まとめ

核はリボソームの生産を組織し,その構造に特定の処理ステップが結びついています. 5' 外部トランスクリプトされたスペーサー処理の障害は小さなサブユニット出力と核構造に影響し,細胞増殖に影響します.

科学分野:

細胞生物学
分子生物学
進化生物学

背景:

核細胞はリボソーム生物生成の中心であり,リボソームRNA (rRNA) の前駆者を複雑に処理する.
核子構造内のこれらの処理段階の正確な空間的組織と細胞のニーズへの適応は完全に理解されていません.

研究の目的:

リボソームサブユニット前駆体 (pre-rRNA) の処理の空間時間的動態をヒトの核部内で調査する.
rRNA前処理,核構造,細胞増殖の関係を解明する.
核構造がリボソーム生物生成の効率に及ぼす進化的影響について調べる.

主な方法:

人間の核細胞におけるrRNA前処理の空間時間分析
5' 外部トランスクリブされたスペーサー (5' ETS) 処理の混乱の影響を調査する.
胎児と胎児の核構造の比較分析

主要な成果:

小型サブユニット (SSU) プロセソームは,線維中心 (FC) - 密度の高い線維成分 (DFC) - 周辺密度の高い線維成分 (PDFC) ドメインに局所され,大型のサブユニット (LSU) のプレ-rRNAはPDFC-粒子の成分領域に通過する.
ゆっくり増殖する細胞は,FC-DFCユニットの改造とSSU前駆体輸出の減少に関連した5' ETS中心のSSU処理を損なう.
アナミオットの二重核は,5' ETSの分布が異なっており,アンニオットの多層核と比較してrRNA前流が遅い.
FC/DFCインターフェースを導入することで,二重核細胞の処理効率が向上しました.

結論:

ETSを中心とした処理は,核構造と効率的なSSU生殖を維持するために不可欠です.
核細胞構造,特に胎盤細胞の FC-DFC ユニットは,rRNA 前処理に最適化されています.
核構造の進化的差異は,リボソーム生殖効率の差異と相関している.

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