Investigation of the mechanisms involved in the assembly of COPI-coated vesicles by cryo-electron microscopy

除了允许生命形式存在外，细胞膜还将真核细胞内部组织成生物化学上不同的隔间，在这些隔间中执行特定的细胞功能。蛋白质(货物)在不连续的亚细胞室之间的运输依赖于多层外壳蛋白复合体在细胞膜上的组装和拆解。到目前为止，已经描述了三种主要类型的囊泡：笼蛋白、COPI(外壳蛋白复合体I)和COPII(外壳蛋白复合体II)包裹的囊泡。包被蛋白的囊泡发芽于质膜、反高尔基网络(TGN)和内体。被Copi包被的囊泡主要从高尔基体到内质网(ER)和高尔基体池之间运输。包被COPII的囊泡从内质网到高尔基体。笼蛋白和COPII包被囊泡的结构最近被发表。虽然这些囊泡似乎有一些共同的机械设计，但在组装囊泡的方式上有很大的差异。

In addition to allow life forms to exist, cellular membranes organize the interior of the eukaryotic cell into biochemically distinct compartments in which specific cellular functions are performed. The transport of proteins (cargo) between discontinuous sub-cellular compartments relies on the assembly and disassembly of multilayered coat protein complexes (CPCs) onto cellular membrane. To-date, three major types of vesicles have been described: clathrin-, COPI (coat protein complex I)- and COPII (coat protein complex II)-coated vesicles. Clathrin-coated vesicles bud from the plasma membrane, trans-Golgi network (TGN) and endosomes. COPI-coated vesicles traffic primarily from the Golgi to the endoplasmic reticulum (ER) and between Golgi cisternae. COPII-coated vesicles traffic from the ER to the Golgi. The structures of clathrin and COPII coated vesicles have recently been published. Although these vesicles appear to share some common mechanical designs, there are significant differences in the way the vesicles are assembled.