Identification of a novel member of the chloride intracellular channel gene family (CLIC5) that associates with the actin cytoskeleton of placental microvilli
Identification of a novel member of the chloride intracellular channel gene family (CLIC5) that associates with the actin cytoskeleton of placental microvilli
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DOI：
10.1091/mbc.11.5.1509
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发表时间：
2000-05-01
影响因子：
3.3
通讯作者：
Bretscher, A
中科院分区：
文献类型：
--
作者：
Berryman, M;Bretscher, A
细胞内氯离子通道（CLIC）基因家族参与了多种亚细胞内氯离子的转运。我们在这里报告的分子，生化和细胞特性的一个新成员，这个基因家族称为CLIC 5。CLIC 5是从胎盘微绒毛提取物中分离的，作为由几种已知的细胞骨架蛋白组成的多聚体复合物的组分，包括肌动蛋白、埃兹蛋白、α-辅肌动蛋白、凝溶胶蛋白和IQGAP 1。我们克隆了人cDNA并产生了CLIC 5、CLIC 1/NCC 27和CLIC 4/huH 1/p64 H1特异性抗体。北方印迹分析显示，CLIC 5与人CLIC 1、CLIC 2、CLIC 3和CLIC 4具有52-76%的总体同一性。CLIC 5与CLIC 1和CLIC 4相比具有不同的表达模式。胎盘组织提取物的免疫印迹分析表明，CLIC 4和CLIC 5富集在分离的胎盘微绒毛，而CLIC 1不是。此外，与CLIC 1和CLIC 4相反，CLIC 5与微绒毛的洗涤剂不溶性细胞骨架部分相关。间接免疫荧光显微镜显示CLIC 4和CLIC 5集中在滋养层的上皮区域内，而CLIC 1分布在整个细胞质中。这些研究表明，CLIC 1，CLIC 4和CLIC 5在氯离子转运中发挥不同的作用，CLIC 5与极化上皮细胞中的皮质肌动蛋白细胞骨架相互作用。
The chloride intracellular channel (CLIC) gene family has been implicated in chloride ion transport within various subcellular compartments. We report here the molecular, biochemical, and cellular characterization of a new member of this gene family termed CLIC5. CLIC5 was isolated from extracts of placental microvilli as a component of a multimeric complex consisting of several known cytoskeletal proteins, including actin, ezrin, alpha-actinin, gelsolin, and IQGAP1. We cloned human cDNAs and generated antibodies specific for CLIC5, CLIC1/NCC27, and CLIC4/huH1/ p64H1. CLIC5 shares 52-76% overall identity with human CLIC1, CLIC2, CLIC3, and CLIC4, Northern blot analysis showed. that CLIC5 has a distinct pattern of expression compared with CLIC1 and CLIC4. Immunoblot analysis of extracts from placental tissues demonstrated that CLIC4 and CLIC5 are enriched in isolated placental microvilli, whereas CLIC1 is not. Moreover, in contrast to CLIC1 and CLIC4, CLIC5 is associated with the detergent-insoluble cytoskeletal fraction of microvilli. Indirect immunofluorescence microscopy revealed that CLIC4 and CLIC5 are concentrated within the epical region of the trophoblast, whereas CLIC1 is distributed throughout: the cytoplasm. These studies suggest that CLIC1, CLIC4, and CLIC5 play distinct roles in chloride transport and that CLIC5 interacts with the cortical actin cytoskeleton in polarized epithelial cells.