Hubrecht Institute, Royal Netherlands Academy of Arts and Sciences (KNAW) and UMC UtrechtUtrecht, Netherlands; The Department of Cell Biology, University Medical Center UtrechtUtrecht, Netherlands.
Department of Biological Sciences, Carnegie Mellon University Pittsburgh, PA, USA.
Front Cell Dev Biol. 2016 Jan 26;4:1. doi: 10.3389/fcell.2016.00001. eCollection 2016.
Originally identified as Golgi stacking factors in vitro, the Golgi reassembly stacking protein (GRASP) family has been shown to act as membrane tethers with multiple cellular roles. As an update to previous comprehensive reviews of the GRASP family (Giuliani et al., 2011; Vinke et al., 2011; Jarvela and Linstedt, 2012), we outline here the latest findings concerning their diverse roles. New insights into the mechanics of GRASP-mediated tethering come from recent crystal structures. The models of how GRASP65 and GRASP55 tether membranes relate directly to their role in Golgi ribbon formation in mammalian cells and the unlinking of the ribbon at the onset of mitosis. However, it is also clear that GRASPs act outside the Golgi with roles at the ER and ER exit sites (ERES). Furthermore, the proteins of this family display other roles upon cellular stress, especially in mediating unconventional secretion of both transmembrane proteins (Golgi bypass) and cytoplasmic proteins (through secretory autophagosomes).
最初在体外被鉴定为高尔基堆叠因子，高尔基重装配堆叠蛋白 (GRASP) 家族已被证明作为具有多种细胞作用的膜系绳。作为对 GRASP 家族的先前全面综述的更新（Giuliani 等人，2011 年；Vinke 等人，2011 年；Jarvela 和 Linstedt，2012 年），我们在这里概述了它们的最新发现关于他们的不同角色。关于 GRASP 介导的系绳的力学的新见解来自最近的晶体结构。GRASP65 和 GRASP55 系膜的模型直接与其在哺乳动物细胞中高尔基带形成中的作用以及在有丝分裂开始时带的解链有关。然而，很明显 GRASPs 在外高尔基体内发挥作用，在 ER 和 ER 出口部位 (ERES) 发挥作用。此外，该家族的蛋白质在细胞应激时表现出其他作用，特别是在介导跨膜蛋白的非常规分泌（高尔基旁路）和细胞质蛋白（通过分泌自噬体）方面。
