NHERF1 regulates actin cytoskeleton organization through modulation of α-actinin-4 stability
NHERF1 regulates actin cytoskeleton organization through modulation of α-actinin-4 stability
复制标题
NHERF1 通过调节 α-actinin-4 稳定性来调节肌动蛋白细胞骨架组织。
DOI：
10.1096/fj.15-275586
复制
发表时间：
2016-02-01
期刊：
影响因子：
4.8
通讯作者：
He, Junqi
中科院分区：
文献类型：
--
作者：
Sun, Licui;Zheng, Junfang;He, Junqi
肌动蛋白细胞骨架由高度动态的丝状蛋白网络组成，但调节其组织和重塑的分子机制仍然难以捉摸。在这项研究中，Na+/H+交换调节因子（NHERF）-1的功能丧失和功能获得的实验表明，在HeLa细胞中的聚合肌动蛋白细胞骨架（F-actin）被NHERF 1打乱，而肌动蛋白的表达水平没有表现出可检测的变化。为了阐明肌动蛋白细胞骨架解体的NHERF 1的分子机制，一个组合的二维荧光-基质辅助激光解吸/电离-飞行时间质谱法的方法被用来筛选蛋白质的NHERF 1调节HeLa细胞。α-肌动蛋白-4是一种肌动蛋白交联蛋白。谷胱甘肽S-转移酶下拉和免疫共沉淀研究表明，α-辅肌动蛋白-4羧基末端区域特异性与NHERF 1突触后密度95/盘-大/β-occludens-1结构域相互作用。NHERF 1/α-辅肌动蛋白-4相互作用增加α-辅肌动蛋白-4泛素化并降低其表达水平，导致肌动蛋白细胞骨架解体。我们的研究确定α-辅肌动蛋白-4作为一种新的NHERF 1相互作用的伙伴，并提供了新的见解肌动蛋白细胞骨架的调节机制NHERF 1。
The actin cytoskeleton is composed of a highly dynamic network of filamentous proteins, yet the molecular mechanism that regulates its organization and remodeling remains elusive. In this study, Na+/H+ exchanger regulatory factor (NHERF)-1 loss-of-function and gain-of-function experiments reveal that polymerized actin cytoskeleton (F-actin) in HeLa cells is disorganized by NHERF1, whereas actin protein expression levels exhibit no detectable change. To elucidate the molecular mechanism underlying actin cytoskeleton disorganization by NHERF1, a combined 2-dimensional electrophoresis-matrix-assisted laser desorption/ionization-time of flight mass spectrometry approach was used to screen for proteins regulated by NHERF1 in HeLa cells. alpha-Actinin-4, an actin cross-linking protein, was identified. Glutathione S-transferase pull-down and coimmunoprecipitation studies showed the alpha-actinin-4 carboxyl-terminal region specifically interacted with the NHERF1 postsynaptic density 95/disc-large/zona occludens-1 domain. The NHERF1/alpha-actinin-4 interaction increased alpha-actinin-4 ubiquitination and decreased its expression levels, resulting in actin cytoskeleton disassembly. Our study identified alpha-actinin-4 as a novel NHERF1 interaction partner and provided new insights into the regulatory mechanism of the actin cytoskeleton by NHERF1.