Blokhin National Medical Research Center of Oncology, Ministry of Health of the Russian Federation, Moscow, 115478, Russia.
Biochemistry (Mosc). 2020 Feb;85(2):177-191. doi: 10.1134/S0006297920020054.
Exosomes (secreted extracellular vesicles formed in the intracellular vesicular transport system) play a crucial role in distant cell-cell communication. Exosomes transfer active forms of various biomolecules; the molecular composition of the exosomal cargo is a result of targeted selection and depends on the type of producer cells. The mechanisms underlying exosome formation and cargo selection are poorly understood. It is believed that there are several pathways for exosome biogenesis, although the questions about their independence and simultaneous coexistence in the cell still remain open. The least studied topic is the recently discovered mechanism of exosome formation associated with lipid rafts, or membrane lipid microdomains. Here, we present modern concepts and basic hypotheses on the mechanisms of exosome biogenesis and secretion and summarize current data on the involvement of lipid rafts and their constituent molecules in these processes. Special attention is paid to the analysis of possible role in the exosome formation of raft-forming proteins of the SPFH family, components of planar rafts, and caveolin, the main component of caveolae.
外泌体（在细胞内囊泡运输系统中形成的分泌型细胞外囊泡）在远距离细胞间通讯中发挥着关键作用。外泌体可传递各种生物分子的活性形式；外泌体货物的分子组成是靶向选择的结果，取决于产生细胞的类型。外泌体形成和货物选择的机制尚未完全明了。尽管关于它们在细胞中是否独立存在以及同时共存的问题仍存在争议，但人们认为存在几种外泌体生物发生途径。脂质筏或膜脂微区相关的外泌体形成机制是研究最少的课题。本文介绍了关于外泌体生物发生和分泌机制的现代概念和基本假设，并总结了当前关于脂质筏及其组成分子参与这些过程的最新数据。特别关注分析 SPFH 家族的形成筏状蛋白、平面筏的组成成分以及质膜微囊泡的主要成分窖蛋白在形成外泌体过程中的可能作用。
