GRASP depletion–mediated Golgi destruction decreases cell adhesion and migration via the reduction of a5ß1 integrin

Ahat, Erpan; Xiang, Yi; Zhang, Xiaoyan; Bekier, Michael E.; Wang, Yanzhuang

Cell attachment depends on a set of cell adhesion proteins called integrins; α5β1 integrin is the main form of integrin complex in HeLa and MDA-MB-231 cells (Mierke et al., 2011; Yu et al., 2011; Jia et al., 2016) . As highly glycosylated transmembrane proteins, α5 and β1 integrins are processed by the Golgi and transported to the plasma membrane for their proper functions. When transported through the TGN, α5 integrin undergoes posttranslational cleavage for activation, wherein pro-integrin α5 (∼170 kDa) is cleaved by pro-protein convertases (PCs) into heavy (∼130 kDa) and light (∼19 kDa) chains that are linked by a disulfide bond (Paule et al., 2012) . Because GRASP depletion accelerates α5-integrin trafficking and processing (Xiang et al., 2013) , it is reasonable to expect that it may also affect α5-and β1-integrin glycosylation and sorting as well as cell attachment.