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在小鼠肝脏中,FicD调节了对未折叠蛋白质反应的适应
Amanda K Casey1, Nathan M Stewart1, Naqi Zaidi2
1Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA; Howard Hughes Medical Institute, Dallas, TX, 75390, USA.
Biochimie
|May 13, 2024
概括
酶FicD在生理压力期间调节未折叠蛋白反应 (UPR). 虽然缺乏FicD的肝脏组织表现出弹性,但它适应重复的压力,表明组织在UPR调节中的特定作用.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生理学 生理学 生理学
背景情况:
- 展开的蛋白质反应 (UPR) 是一种关键的细胞机制,用于管理由错误折叠的蛋白质引起的内质网膜 (ER) 压力.
- 失调的UPR可能导致细胞功能障碍和组织损伤,需要精确的调节控制.
- 酶FicD (也称为Fic或HYPE) 之前已被确定通过通过AMPylation/deAMPylation对BiP的翻译后修饰来调节UPR.
研究的目的:
- 调查FicD在调节小鼠肝脏中UPR中的作用,特别是在对生理和病理压力的反应中.
- 为了确定FicD在胰腺中已知的调节功能是否延伸到肝脏组织,考虑潜在的组织特异性差异.
- 探索FicD参与减轻有害的UPR影响和适应重复的肝脏压力.
主要方法:
- 使用FicD淘汰 (FicD-/-) 鼠标来评估UPR信号和组织损伤.
- 暴露于生理压力因素 (禁食/食) 和病理压力因素 (慢性高脂肪饮食,急性UPR诱导) 的小鼠.
- 监测UPR信号,组织损伤标志物和体重变化,以应对各种压力条件.
主要成果:
- 缺乏FicD的肝脏在短期生理性禁食和食压力期间表现出增强的UPR信号,类似于胰腺研究.
- 尽管增强了UPR信号,但FicD-/-肝脏在长期高脂肪饮食或急性病理性UPR诱导下表现出了显著的弹性,没有显著的损伤.
- 在FicD-/-小鼠中,在重复的病理性UPR诱导后,UPR诱导和体重减轻模式发生了变化,这表明它在应激适应中发挥了作用.
结论:
- 在肝脏中轻微的生理压力期间,FicD在调节UPR方面发挥作用.
- 即使在没有FicD的情况下,肝脏组织也表现出对诱导UPR的条件的显著弹性,突出了组织特异性的补偿机制.
- FicD参与了对重复应激的适应,其要求显示了组织特异性的差异.
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