核心的早晨钟组件CCA1增强了UPR目标基因表达,以促进ER应激恢复
Gyeongik Ahn1, In Jung Jung2, Gyeong-Im Shin1
1Division of Applied Life Science (BK21 Four), PBRRC, PMBBRC, RILS & IALS, Gyeongsang National University, Jinju 52828, Republic of Korea.
Plant communications
|February 15, 2025
概括
昼夜时钟调节了植物的生长时间.
科学领域:
- 植物生物学 植物生物学
- 分子生物学分子生物学
- 细胞应激反应的细胞应激反应
背景情况:
- 细胞内膜网膜 (ER) 管理蛋白质的合成和折叠.
- 当蛋白质折叠能力被压倒时,ER应激会发生,引发未折叠蛋白质反应 (UPR).
- 植物UPR基因表达遵循每日循环,但时钟调节机制尚不清楚.
研究的目的:
- 为了研究昼夜时钟在调节植物在ER压力期间的UPR基因表达中的作用.
- 阐明昼夜时钟影响ER应激耐受性的机制.
主要方法:
- 在一天中的不同时间对根生长中ER应激敏感性的分析.
- 在ER压力条件下研究UPR基因表达.
- 通过突变分析和分子技术研究CIRCADIAN CLOCK ASSOCIATED 1 (CCA1) 和基本氨酸拉链28 (bZIP28) 之间的相互作用.
主要成果:
- 根生长中的ER应激敏感性显示出明显的日间时间阶段.
- 在CCA1的突变显著损害了ER压力的恢复.
- CCA1与bZIP28形成一个复合体,作为ER应力恢复的上游调节器.
- 在ER应激时,CCA1与BiP3促进器的bZIP28结合,增强反应.
结论:
- 昼夜时钟,特别是CCA1,在ER压力期间调节UPR基因表达.
- CCA1和bZIP28协作管理一个依赖于时间的适应性应对ER压力的反应,维持蛋白质静止.
- 昼夜时钟预测并优化ER陪伴者表达,以提高应激耐受性.
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