rRNA转录是相分离和核结构维护的组成部分
Soma Dash1, Maureen C Lamb1, Jeffrey J Lange1
1Stowers Institute for Medical Research, Kansas City, Missouri, United States of America.
PLoS genetics
|August 28, 2023
概括
RNA聚合酶I (Pol I) 转录对于核糖体生物发生和核结构至关重要. 破坏Pol I功能会导致细胞核异常,影响发育和疾病的发病.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 发展生物学 发展生物学
背景情况:
- 通过RNA聚合酶I (Pol I) 驱动的核糖体RNA (rRNA) 转录驱动的核糖体生物发生,对于细胞生长至关重要.
- 核糖体生物发生的失调会导致核糖体病变,并改变核细胞结构.
- 在发育和疾病中,连接rRNA转录,核糖体生物发生和核细胞结构的精确机制尚未完全理解.
研究的目的:
- 研究Pol I子单元在rRNA转录和核糖体生物发生中的作用.
- 阐明Pol I功能如何影响胚胎发育期间和疾病模型中的细胞核结构.
- 了解受Pol I抑制影响的细胞核的物理性质.
主要方法:
- 在Pol I子单元 (Polr1a,Polr1b,Polr1c,Polr1d) 中生成和分析同卵性零突变.
- 在植入前和中期胚胎以及人类诱导多能干细胞 (hiPSCs) 中药理抑制Pol I.
- 微观分析核细胞形态,包括核细胞前体和总体体积.
- 评估核细胞区的粘度和相分离特性.
主要成果:
- 完全丧失Pol I功能导致了植入前的致命性.
- 突变的Pol I子单元破坏了核细胞结构,其特点是前体较少,核细胞扩大,凝结.
- 在胚胎和hiPSC中抑制Pol I会导致单个凝聚或碎片化的核细胞.
- 抑制rRNA转录会增加核粘度,破坏相位分离并导致核凝结.
- 缺少rRNA转录会阻止核细胞在线分裂后重组,导致核细胞碎片化.
结论:
- 聚I功能和rRNA转录对于维持正常的核细胞结构和完整性至关重要.
- 改变的Pol I活动显著影响核细胞形态,对发育和核糖体病变有影响.
- 核粘度和相分离的变化是Pol I抑制引起的结构缺陷的关键机制.
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