IQGAP1通过NDUFS4替代拼接介导核和线粒体之间的通信
Vasiliki Papadaki1, Zoi Erpapazoglou1, Maria Kokkori1
1Institute for Fundamental Biomedical Research, BSRC "Al. Fleming", Vari 16672, Greece.
NAR cancer
|August 28, 2023
概括
IQGAP1通过控制复合I子单元的替代拼接来调节胃癌中的线粒体呼吸. 这一发现揭示了IQGAP1在线粒体质量控制和癌细胞适应中的新角色.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 癌症研究 癌症研究
背景情况:
- 线粒体-核的通信对于细胞平衡和应激适应至关重要.
- 癌细胞中的线粒体功能失调促进了癌细胞的增殖,攻击性和治疗耐药性.
- 替代拼接 (AS) 在核线粒体通信中的作用在很大程度上尚未被探索.
研究的目的:
- 通过胃癌的替代拼接来研究IQGAP1在调节线粒体功能的作用.
- 阐明IQGAP1对线粒体呼吸和复合I组装的影响.
主要方法:
- 对IQGAP1淘汰赛 (KO) 和父母胃癌细胞的蛋白质和RNA测序分析.
- 评估线粒体呼吸链复合物I (CI) 的活性和亚单元表达.
- 对替代拼接事件的分析,特别是对NDUFS4基因.
主要成果:
- IQGAP1调节影响线粒体呼吸的替代拼接事件.
- IQGAP1缺陷 (KO) 改变了NDUFS4的拼接,并降低了其他CI子单元的调节.
- IQGAP1 KO细胞表现出CI组合受损和CI活性降低,模仿利氏综合征.
- IQGAP1的再表达可以扭转这些线粒体缺陷.
结论:
- 在胃癌中,IQGAP1通过替代拼接在线粒体质量控制中发挥着新的作用.
- IQGAP1微调复杂I活性,对于依赖于线粒体呼吸的胃癌细胞至关重要.
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