Vaughan Kevin T
Department of Biological Sciences, P.O. Box 369, University of Notre Dame, Notre Dame, IN 46556, USA.
Biochim Biophys Acta. 2005 Jul 10;1744(3):316-24. doi: 10.1016/j.bbamcr.2005.05.001.
The intimate link between microtubule (MT) organization and the components of the secretory pathway has suggested that MT-based motility is an essential component of vesicular membrane transport and membrane polarization. The molecular details of these processes are still under investigation; however, a novel class of MT plus end-binding proteins shed new light on transport between the endoplasmic reticulum (ER) and Golgi apparatus. The dynactin complex, an initial member of this family, shares localization and live-cell imaging phenotypes with other plus end-binding proteins such as CLIP-170 and EB1. In addition, dynactin has been shown to mediate the binding of ER-Golgi transport vesicles to MTs through a regulated MT-binding motif in p150(Glued). Whereas the plus end-binding activity of CLIP-170 and EB1 has been linked to the regulation of dynamic instability, the plus end binding of dynactin is implicated in a search-capture mechanism for dynein-dependent cargoes. An examination of dynactin's role in ER-Golgi transport suggests that plus end binding could be a reflection of fundamental membrane transport mechanisms.
微管（MT）组织与分泌途径的组成部分之间的紧密联系表明，基于微管的运动性是囊泡膜运输和膜极化的重要组成部分。这些过程的分子细节仍在研究中；然而，一类新的微管正端结合蛋白为内质网（ER）和高尔基体之间的运输提供了新的线索。动力蛋白复合体是该家族的初始成员，与其他正端结合蛋白如CLIP-170和EB1具有共同的定位和活细胞成像表型。此外，动力蛋白已被证明通过p150（Glued）中一个受调控的微管结合基序介导内质网-高尔基体运输囊泡与微管的结合。虽然CLIP-170和EB1的正端结合活性与动态不稳定性的调节有关，但动力蛋白的正端结合与动力蛋白依赖性货物的搜索捕获机制有关。对动力蛋白在内质网-高尔基体运输中作用的研究表明，正端结合可能反映了基本的膜运输机制。
