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在骨肌肉中OPA1删除后,线粒体内质网膜结合的ATF4依赖性增加

Antentor Hinton^1,2,3, Prasanna Katti⁴, Margaret Mungai^1,2

¹Department of Internal Medicine, Division of Endocrinology and Metabolism, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA.

Journal of cellular physiology

|February 29, 2024

概括

骨肌中的线粒体光学缩1 (OPA1) 缺陷导致线粒体与ER接触更加紧密. 这由综合应激反应通路效应器介导,激活转录因子4 (ATF4).

科学领域:

细胞生物学细胞生物学
线粒体生物学线粒体生物学
肌肉生理学肌肉生理学

背景情况:

线粒体和内质网膜接触部位 (MERCs) 对于器官间通信至关重要.
在MERC中存在的缺陷与氧化应激和肌肉病理有关.
光学缩1 (OPA1) 是一个线粒体融合调解器;它的骨肌特异性淘汰 (KD) 之前诱导了ER压力.

研究的目的:

调查假设,骨肌细胞中的OPA1下调会改变MERC形成的假设.
阐明OPA1在调节MERC结构和功能的作用.
确定综合应激反应 (ISR) 途径在OPA1介导的MERC变化中的参与.

主要方法:

在多个肌细胞系统中评估了MERC形成,包括小鼠和Drosophila模型,以及初级肌管.
评估MERC蛋白质的丰度,特别是那些参与交换的蛋白质.
测量了线粒体和肉质网膜水平.
研究了通过减少其表达来激活转录因子4 (ATF4) 的作用.

主要成果:

OPA1 缺陷导致了更紧密,更频繁的 MERC.
观察到更多的参与交换的MERC蛋白质.
失去OPA1增加了ATF4的表达,这是ISR效应因子.
减少Atf4表达可以防止OPA1损失引起的MERC收紧.
减少OPA1降低了线粒体和肉质网膜的含量,而ATF4抑制可以逆转这种情况.

结论:

由OPA1缺乏引起的线粒体应激调节了骨肌肉的MERC形成.
这种规则以ATF4依赖的方式发生.
OPA1在维持MERC平衡和骨肌肉中的信号传递方面发挥着至关重要的作用.

关键词:

激活转录因子4的作用细胞内膜网膜的内oplasmic网膜.综合应激反应综合应激反应机关间的沟通是机关间的沟通.线粒体中的线粒体.

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