核斑蛋白形成内在的和依赖MALAT1的微相
Min Kyung Shinn1, Dylan T Tomares1, Vicky Liu1
1Department of Biomedical Engineering, Washington University in St. Louis, St. Louis, MO 63130, USA; Center for Biomolecular Condensates, James McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO 63130, USA.
Cell
|December 20, 2025
概括
像SRSF和TDP-43这样的核斑蛋白通过共聚物相互作用形成不同的微相. 这些微相组件受到RNA的影响,影响细胞组织和功能.
科学领域:
- 分子生物学
- 生物化学
- 细胞生物学
背景情况:
- 核斑中含有前mRNA处理因子,包括富含氨酸/氨酸的拼接因子 (SRSF) 和交换反应DNA结合蛋白 (TDP-43).
- 这些蛋白质具有RNA识别基因 (RRM) 和无序区域,作为独特的块共聚物.
研究的目的:
- 研究核斑蛋白在驱动微相分离和组合中的域间相互作用的作用.
- 了解RNA分子,特别是MALAT1如何影响这些蛋白质微相.
主要方法:
- 对蛋白质结构功能关系的分析,重点是区块共聚物特性.
- 在体外和细胞环境中观察和描述微相形成和组装动态.
- 研究特定的RNA-蛋白相互作用,特别是MALAT1与SRSF1和TDP-43微相.
主要成果:
- SRSF和TDP-43形成不同的微相 (23-45 nm),由同型和异型的吸引力/排斥力驱动.
- 微米级的SRSF组合与这些微相的集群一致.
- 转移相关的肺腺癌转录1 (MALAT1) lncRNA结合SRSF1微相并破坏TDP-43微相的稳定.
- 蛋白质混合物通过微相相互作用形成微米级的核心外结构.
结论:
- 具有折叠和无序区域的共聚物内的相互作用对于驱动微相形成至关重要.
- 这些微相行为有助于核斑点的组织,并影响RNA处理.
- 特定的lncRNA可以调节不同蛋白质微相的行为,突出调节机制.
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