Mitochondrial-Derived Compartments are Multilamellar Domains that Encase Membrane Cargo and Cytosol.
Mitochondrial-Derived Compartments are Multilamellar Domains that Encase Membrane Cargo and Cytosol.
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线粒体衍生的区室是包裹膜货物和细胞溶胶的多层结构域。
DOI：
10.1101/2023.07.07.548169
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Hughes,AdamL
中科院分区：
文献类型：
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作者：
Wilson,ZacharyN;West,Matt;English,AlyssaM;Odorizzi,Greg;Hughes,AdamL
保持线粒体网络的健康对细胞的生存和长寿至关重要。为此，线粒体采用了几种膜重塑机制，包括形成线粒体衍生的小泡(MDV)和隔室(MDC)来选择性地移除部分细胞器。与特征良好的MDV相比，MDC的形成和组成的区别特征仍然不清楚。在这里，我们使用电子断层扫描观察到，MDCs形成大的多层结构域，在ER-线粒体接触部位的线粒体管中产生同心球形隔室。MDC生物发生的时间推移荧光显微镜显示，线粒体膜延伸反复拉长、合并和内陷形成这些包裹多层膜的间隔。因此，MDCs强烈隔离外线粒体膜的一部分，将膜货物固定到受保护的区域，同时也将胞液物质包裹在MDC管腔内。总而言之，我们的结果为MDC的形成提供了一个模型，并描述了将MDDC与其他先前发现的线粒体结构和货物分拣结构域区分开来的关键特征。
Preserving the health of the mitochondrial network is critical to cell viability and longevity. To do so, mitochondria employ several membrane remodeling mechanisms, including the formation of mitochondrial-derived vesicles (MDVs) and compartments (MDCs) to selectively remove portions of the organelle. In contrast to well-characterized MDVs, the distinguishing features of MDC formation and composition remain unclear. Here, we used electron tomography to observe that MDCs form as large, multilamellar domains that generate concentric spherical compartments emerging from mitochondrial tubules at ER–mitochondria contact sites. Time-lapse fluorescence microscopy of MDC biogenesis revealed that mitochondrial membrane extensions repeatedly elongate, coalesce, and invaginate to form these compartments that encase multiple layers of membrane. As such, MDCs strongly sequester portions of the outer mitochondrial membrane, securing membrane cargo into a protected domain, while also enclosing cytosolic material within the MDC lumen. Collectively, our results provide a model for MDC formation and describe key features that distinguish MDCs from other previously identified mitochondrial structures and cargo-sorting domains.