Department of Neurology, University of Massachusetts Chan Medical School, Worcester, MA, USA.
Department of Biotechnology and Biological Sciences, Hannam University, Yuseong-gu, Daejeon, Republic of Korea.
Autophagy. 2023 Jul;19(7):2045-2061. doi: 10.1080/15548627.2023.2169309. Epub 2023 Feb 27.
Dysfunction of the endosomal sorting complex required for transport (ESCRT) has been linked to frontotemporal dementia (FTD) due in part to the accumulation of unsealed autophagosomes. However, the mechanisms of ESCRT-mediated membrane closure events on phagophores remain largely unknown. In this study, we found that partial knockdown of non-muscle MYH10/myosin IIB/zip rescues neurodegeneration in both and human iPSC-derived cortical neurons expressing FTD-associated mutant CHMP2B, a subunit of ESCRT-III. We also found that MYH10 binds and recruits several autophagy receptor proteins during autophagosome formation induced by mutant CHMP2B or nutrient starvation. Moreover, MYH10 interacted with ESCRT-III to regulate phagophore closure by recruiting ESCRT-III to damaged mitochondria during PRKN/parkin-mediated mitophagy. Evidently, MYH10 is involved in the initiation of induced but not basal autophagy and also links ESCRT-III to mitophagosome sealing, revealing novel roles of MYH10 in the autophagy pathway and in ESCRT-related FTD pathogenesis. ALS: amyotrophic lateral sclerosis; AP: autophagosome; Atg: autophagy-related; ESCRT: endosomal sorting complex required for transport; FTD: frontotemporal dementia.
内体分选复合物需要运输(ESCRT)的功能障碍与额颞叶痴呆(FTD)有关,部分原因是未密封的自噬体的积累。然而,ESCRT 介导的吞噬体膜闭合事件的机制在很大程度上仍然未知。在这项研究中,我们发现非肌肉肌球蛋白 10/肌球蛋白 IIB/zip 的部分敲低可挽救 和表达 FTD 相关突变 CHMP2B(ESCRT-III 的一个亚基)的人 iPSC 衍生皮质神经元中的神经退行性变。我们还发现,在突变 CHMP2B 或营养饥饿诱导的自噬体形成过程中,MYH10 结合并募集几种自噬受体蛋白。此外,MYH10 通过在 PRKN/parkin 介导的线粒体自噬过程中募集 ESCRT-III 到受损的线粒体,与 ESCRT-III 相互作用以调节吞噬体的闭合。显然,MYH10 参与了诱导的但不是基础的自噬的起始,并且还将 ESCRT-III 与噬粒体密封联系起来,揭示了 MYH10 在自噬途径和 ESCRT 相关 FTD 发病机制中的新作用。ALS:肌萎缩侧索硬化症;AP:自噬体;Atg:自噬相关;ESCRT:内体分选复合物需要运输;FTD:额颞叶痴呆。