JACOP, a novel plaque protein localizing at the apical junctional complex with sequence similarity to cingulin
JACOP, a novel plaque protein localizing at the apical junctional complex with sequence similarity to cingulin
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DOI：
10.1074/jbc.m402616200
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发表时间：
2004-10-29
影响因子：
4.8
通讯作者：
Furuse, M
中科院分区：
文献类型：
--
作者：
Ohnishi, H;Nakahara, T;Furuse, M
顶结复合体由各种细胞粘附分子和细胞质斑块蛋白组成。利用一种单克隆抗体识别位于鸡顶端连接复合体的155-kDa细胞质抗原（p155），我们克隆了其小鼠同源基因cDNA。小鼠p155的全长cDNA编码了一个148 kda的多肽，该多肽含有一个与紧密连接（TJ）相关的斑块蛋白cingulin序列相似的卷曲结构域。我们将该蛋白命名为JACOP （connection -associated coil -coil protein）。免疫荧光染色显示，JACOP在各种类型上皮细胞和内皮细胞的连接复合体中富集。此外，在肝脏和肾脏中，JACOP也沿非连接肌动蛋白丝分布。免疫电镜观察发现，在肝脏中，JACOP定位于TJs的底被，但在一些组织中，其分布并不局限于TJs，而是延伸到粘附连接区域。过表达研究表明，JACOP被招募到上皮细胞的连接复合体和成纤维细胞的细胞间接触和应激纤维中。这些发现表明JACOP参与将顶端连接复合体，特别是TJs锚定到基于肌动蛋白的细胞骨架上。
The apical junctional complex is composed of various cell adhesion molecules and cytoplasmic plaque proteins. Using a monoclonal antibody that recognizes a chicken 155-kDa cytoplasmic antigen (p155) localizing at the apical junctional complex, we have cloned a cDNA of its mouse homologue. The full-length cDNA of mouse p155 encoded a 148-kDa polypeptide containing a coiled-coil domain with sequence similarity to cingulin, a tight junction (TJ)-associated plaque protein. We designated this protein JACOP (junction-associated coiled-coil protein). Immunofluorescence staining showed that JACOP was concentrated in the junctional complex in various types of epithelial and endothelial cells. Furthermore, in the liver and kidney, JACOP was also distributed along nonjunctional actin filaments. Upon immunoelectron microscopy, JACOP was found to be localized to the undercoat of TJs in the liver, but in some tissues, its distribution was not restricted to TJs but extended to the area of adherens junctions. Overexpression studies have revealed that JACOP was recruited to the junctional complex in epithelial cells and to cell-cell contacts and stress fibers in fibroblasts. These findings suggest that JACOP is involved in anchoring the apical junctional complex, especially TJs, to actin-based cytoskeletons.