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过氧体进口压力激活了综合应激反应,并抑制了核糖体生物发生
Jinoh Kim1, Kerui Huang1, Pham Thuy Tien Vo1
1Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, IA 50011, USA.
PNAS nexus
|October 14, 2024
概括
缺陷的过氧体蛋白进口激活了综合应激反应 (ISR) 并抑制了核糖体生物发生. 这种由ATF4介导的细胞应激反应保护细胞免受损伤,并影响rRNA处理.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 机体生物学 机体生物学
背景情况:
- 细胞应激反应对于维持蛋白质平衡至关重要.
- 之前的研究重点是细胞内膜网膜和线粒体应激反应.
- 过氧酶体在细胞应激中的作用及其对进口缺陷的反应尚未得到研究.
研究的目的:
- 为了研究受损的过氧体蛋白质进口的保存细胞应激反应.
- 为了确定涉及到过氧体进口应激的分子通路.
- 探索过氧体功能障碍和核糖体生物生成之间的联系.
主要方法:
- 在果和人类HEK293细胞中的比较转录基因分析 (RNA-seq).
- 在中进行组织特异性过素敲击.
- 在人类细胞中表达主导阴性PEX5C11A.
- 功能分析包括eIF2α酸化和ATF4表达评估.
- 对rRNA加工中间体的分析.
主要成果:
- 在这两种模型系统中,受损的过氧体进口对综合应激反应 (ISR) 进行上调,并对核糖体生物发生进行下调.
- 缺陷的过氧体进口会诱导eIF2α酸化和ATF4表达.
- ATF4激活对抗氧体进口缺陷具有细胞保护作用.
- 过氧体进口应激抑制rRNA处理,导致47S前体的积累.
结论:
- 伊斯兰激素激活和核糖体生物发生抑制是对缺陷的过氧体进口保持的适应性反应.
- ATF4作为一种保护机制,可以防止过氧体进口应激.
- 过氧体功能障碍与改变的rRNA处理有关,揭示了一种新的细胞交声.
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