Department of Biological Sciences, Vanderbilt University, Nashville, TN 37235, USA.
Curr Opin Cell Biol. 2014 Aug;29:67-73. doi: 10.1016/j.ceb.2014.04.009. Epub 2014 May 17.
Distinct trafficking pathways within the secretory and endocytic systems ensure prompt and precise delivery of specific cargo molecules to different cellular compartments via small vesicular (50-150nm) and tubular carriers. The COPI vesicular coat is required for retrograde trafficking from the cis-Golgi back to the ER and within the Golgi stack. Recent structural data have been obtained from X-ray crystallographic studies on COPI coat components alone and on COPI subunits in complex with either cargo motifs or Arf1, and from reconstructions of COPI coated vesicles by electron tomography. These studies provide important molecular information and indicate key differences in COPI coat assembly as compared with clathrin-based and COPII-based coats.
在分泌和内吞系统中，不同的运输途径确保了特定货物分子通过小囊泡（50-150nm）和管状载体快速而精确地递送到不同的细胞区室。COPII 囊泡被认为是负责从顺面高尔基体返回内质网和高尔基体堆叠内的逆行运输。最近的结构数据是通过对 COPI 衣壳成分的 X 射线晶体学研究以及与货物基序或 Arf1 复合的 COPI 亚基的 X 射线晶体学研究，以及通过电子断层摄影术对 COPI 包被囊泡的重建获得的。这些研究提供了重要的分子信息，并表明 COPI 衣壳组装与网格蛋白和 COPII 基的衣壳相比存在关键差异。
