珀克信号通过促进增殖,在内分泌网膜压力下保持血造干细胞池的完整性
bioRxiv : the preprint server for biology
|January 7, 2025
概括
PERK通路对于正常的造血干细胞功能来说不是必不可少的,但被ER压力激活以促进增殖和去除受损细胞,保持池的完整性.
科学领域:
- 细胞生物学 细胞生物学
- 血液学 血液学 血液学
- 分子生物学分子生物学
背景情况:
- 血造干细胞 (HSC) 池的完整性对于终身血液生产至关重要.
- 展开的蛋白质反应 (UPR),特别是PERK通路,与在压力下维持HSC功能有关.
- PERK在HSC命运调节中的确切作用 *in vivo* 仍然在很大程度上未被定义.
研究的目的:
- 在稳定状态和压力条件下调查PERK途径在HSC命运决定中的作用.
- 阐明PERK通过哪些机制影响HSC自我更新和生存 *in vivo*.
- 确定PERK介导的细胞死亡是否是去除受损HSCs的主要机制.
主要方法:
- 利用ER相关降解 (ERAD) 组件 (Sel1L,Hrd1) 的淘汰赛小鼠模型来诱导ER压力.
- 采用遗传PERK淘汰和酶死亡淘汰策略来评估PERK的功能.
- 使用分子和细胞分析分析了HSC的增殖,自我更新潜力和信号通路 (mTOR,ROS).
主要成果:
- 在稳定状态条件下,PERK对于正常的造血和HSC自我更新是不可或缺的.
- 由ERAD缺乏引起的ER压力激活PERK,导致HSC增殖和枯竭,而不是亡.
- PERK的激活通过mTOR信号促进了HSC的过度扩散,损害了自我更新,并消除了压力高的HSC.
- 抑制PERK可以挽救由ERAD缺陷引起的HSC缺陷.
结论:
- 珀克在维护高细胞池完整性方面发挥着至关重要的作用,通过促进通过超增殖去除应激细胞,独立于亡.
- 在ER压力条件下的PERK激活策划了一种非亡机制,以维持HSC平衡.
- 准PERK通路可能为涉及HSC功能障碍的血液学疾病提供治疗策略.
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