Brl1-Brr6在核外聚变中的多功能作用在核孔复合生物发生过程中
Sayan Mondal1,2, Annett Neuner1, Azqa Ajmal Khan3,4
1Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH), Deutsches Krebsforschungszentrum (DKFZ)-ZMBH Allianz, Universität Heidelberg, Heidelberg, 69120, Germany.
The EMBO journal
|February 16, 2026
概括
Brl1 和 Brr6 蛋白质在酵母中的核孔复合体 (NPC) 组装过程中促进核膜 (NE) 融合. 它们弥合了周核空间,确保了适当的NE聚变和NPC插入.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 酵母遗传学 酵母遗传学
背景情况:
- Brl1 和 Brr6 是酵母核外 (NE) 的组成膜蛋白.
- 它们在核孔复合体 (NPC) 组装中的精确作用在很大程度上仍未被定义.
- 这些蛋白质暂时与NPCs结合.
研究的目的:
- 阐明 Brl1 和 Brr6 在酵母 NPC 组件中的特定功能.
- 研究 Brl1 和 Brr6 调节核膜融合的机制.
主要方法:
- 对Brl1和Brr6突变的分析,包括两性α螺旋和保存的氨酸残留突变.
- 使用AlphaFold进行结构预测.
- 调查保存的PAL图案的作用.
- 对PAL突变的过度表达研究.
- 评估核外 (NE) 变形和融合缺陷.
主要成果:
- Brr6在NPC组装的早期和后期阶段都有作用.
- 影响两性α螺旋的突变会影响核素招募,而不会发生NE变形.
- 保存的氨酸残留物中的突变会导致NE变形和缺陷的NE融合.
- Brl1的N端与Nic96相互作用,促进其招募.
- Brl1 和 Brr6 周核域可能通过 PAL 动图在周核空间相互作用.
- 改变这些域的长度会影响NE融合,扩展会导致不受控制的融合和NE分解.
结论:
- Brl1和Brr6对于在NPC组装过程中促进NE聚变至关重要.
- 它们的功能是通过PAL动机相互作用来桥接周核空间.
- 这种相互作用促进了随后的核外融合和NPC插入.
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