He Bing, Guo Wei
Department of Biology, University of Pennsylvania, Philadelphia, PA 19104-6018, USA.
Curr Opin Cell Biol. 2009 Aug;21(4):537-42. doi: 10.1016/j.ceb.2009.04.007. Epub 2009 May 25.
The exocyst is an octameric protein complex, which mediates the tethering of post-Golgi secretory vesicles to the plasma membrane before exocytic fusion. The exocyst assembles by side-by-side packing of rod-shaped subunits composed of helical bundles. The targeting of secretory vesicles to the plasma membrane involves direct interactions of the exocyst with PI(4,5)P(2). In addition, a number of small GTP-binding proteins interact with components of the exocyst and regulate the assembly, localization, and function of this complex. Here we review the recent advances in the field, focusing on the function of the exocyst in polarized exocytosis.
外泌体是一种八聚体蛋白复合物,在胞吐融合之前介导高尔基体后分泌囊泡与质膜的拴系。外泌体通过由螺旋束组成的杆状亚基并排堆积而组装。分泌囊泡靶向质膜涉及外泌体与PI(4,5)P(2)的直接相互作用。此外,一些小GTP结合蛋白与外泌体的组分相互作用并调节该复合物的组装、定位和功能。在此,我们综述该领域的最新进展,重点关注外泌体在极化胞吐作用中的功能。