核包装组装依赖CHMP-7在没有BAF-LEM介导的孔封闭的情况下
Sarah R Barger1, Lauren Penfield1, Shirin Bahmanyar1
1Yale University, Department of Molecular, Cellular, Developmental Biology, 266 Whitney Ave., New Haven, CT 06511, USA.
Journal of cell science
|October 5, 2023
概括
屏障与自集成因子 (BAF) 蛋白质和LEM域蛋白质在围绕轴微管周围的核外 (NE) 孔封闭中发挥着不同的作用. 涉及BAF-LEM结合和LEM-2-CHMP-7的冗余机制确保NE组装和胚胎存活.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 发展生物学 发展生物学
背景情况:
- 屏障与自集成因子 (BAF) 蛋白质交联染色素用于线粒细胞核外 (NE) 组件.
- 众所周知,LAP2-emerin-MAN1 (LEM) 域蛋白和CHMP7可以在螺旋微管周围关闭NE孔.
- BAF-LEM结合在围绕螺旋微管周围的NE孔闭合中的作用仍然不清楚.
研究的目的:
- 调查BAF-LEM结合和LEM-2-CHMP-7在螺旋微管周围NE闭合中的不同作用.
- 探索 BAF-LEM 结合在介相期间的 NE 修复和在线粒分裂期间的 NE 孔关闭中的功能.
- 阐明确保NE组装和胚胎存活的机制.
主要方法:
- 利用受精的Caenorhabditis elegans卵细胞用于研究NE形成.
- 研究了LEM-2,EMR-1,BAF-1和CHMP-7在NE关闭中的作用.
- 分析了受损BAF-LEM结合对NE透性和组装的影响.
主要成果:
- BAF-LEM结合和LEM-2-CHMP-7在线微管周围的NE闭合中表现出不同的作用.
- LEM-2和EMR-1的功能是多余的,BAF-1在NE封闭中.
- 受损的BAF-LEM结合揭示了EMR-1在维持NE透性方面发挥的额外作用.
- 当BAF-LEM结合受损时,LEM-2-CHMP-7对于NE组合和胚胎存活至关重要.
- LEM-2的翅膀螺旋域招募CHMP-7,而LEM-2独立的CHMP-7池也对NE稳定性有所贡献.
结论:
- 围绕螺旋微管的NE孔关闭依赖于冗余机制.
- 在NE组装中,BAF-LEM结合和LEM-2-CHMP-7通路提供了不同的,但合作的功能.
- 这些冗余机制对于保护NE组装和支持胚胎发生至关重要.
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