Exocytosis and endocytosis: modes, functions, and coupling mechanisms.
Exocytosis and endocytosis: modes, functions, and coupling mechanisms.
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DOI：
10.1146/annurev-physiol-021113-170305
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发表时间：
2014
影响因子：
18.2
通讯作者：
Chiang HC
中科院分区：
文献类型：
--
作者：
Wu LG;Hamid E;Shin W;Chiang HC
囊泡胞吐作用释放内容物以介导许多生物事件，包括对脑功能至关重要的突触传递。胞吐后，内吞作用开始，在数秒至数分钟内取回胞吐的囊泡。几十年来对分泌细胞的研究揭示了三种胞吐模式与三种胞吞模式的耦合：（a）完全塌陷融合，其中囊泡塌陷到质膜中，随后是经典的胞吞作用，包括膜内陷和囊泡重组;（B）吻-跑，其中融合孔打开和关闭;和（c）复合胞吐作用，其涉及通过囊泡-囊泡融合形成的巨囊泡的胞吐作用，随后是回收巨囊泡的大量胞吞作用。在这里，我们回顾这些外吞和内吞模式及其在调节量子大小和突触强度，产生突触可塑性，维持胞吐作用，并清除囊泡补充释放网站的作用。此外，我们强调最近的进展，了解囊泡内吞作用是如何启动，从而耦合到胞吐。新出现的模型是，钙离子通过电压依赖性钙通道流入钙微区触发内吞作用并控制内吞速率;钙调蛋白和突触结合蛋白是钙传感器;和胞吐机制，包括SNARE蛋白（小突触蛋白，SNAP 25和突触融合蛋白），需要共同启动内吞作用，可能控制内吞作用的量。
Vesicle exocytosis releases content to mediate many biological events, including synaptic transmission essential for brain functions. Following exocytosis, endocytosis is initiated to retrieve exocytosed vesicles within seconds to minutes. Decades of studies in secretory cells reveal three exocytosis modes coupled to three endocytosis modes: (a) full-collapse fusion, in which vesicles collapse into the plasma membrane, followed by classical endocytosis involving membrane invagination and vesicle reformation; (b) kiss-and-run, in which the fusion pore opens and closes; and (c) compound exocytosis, which involves exocytosis of giant vesicles formed via vesicle-vesicle fusion, followed by bulk endocytosis that retrieves giant vesicles. Here we review these exo- and endocytosis modes and their roles in regulating quantal size and synaptic strength, generating synaptic plasticity, maintaining exocytosis, and clearing release sites for vesicle replenishment. Furthermore, we highlight recent progress in understanding how vesicle endocytosis is initiated and is thus coupled to exocytosis. The emerging model is that calcium influx via voltage-dependent calcium channels at the calcium microdomain triggers endocytosis and controls endocytosis rate; calmodulin and synaptotagmin are the calcium sensors; and the exocytosis machinery, including SNARE proteins (synaptobrevin, SNAP25, and syntaxin), is needed to coinitiate endocytosis, likely to control the amount of endocytosis.