Joberty G, Petersen C, Gao L, Macara I G
Markey Center for Cell Signaling, University of Virginia Health Sciences Center, Charlottesville, Virginia 22908-0577, USA.
Nat Cell Biol. 2000 Aug;2(8):531-9. doi: 10.1038/35019573.
PAR (partitioning-defective) proteins, which were first identified in the nematode Caenorhabditis elegans, are essential for asymmetric cell division and polarized growth, whereas Cdc42 mediates establishment of cell polarity. Here we describe an unexpected link between these two systems. We have identified a family of mammalian Par6 proteins that are similar to the C. elegans PDZ-domain protein PAR-6. Par6 forms a complex with Cdc42-GTP, with a human homologue of the multi-PDZ protein PAR-3 and with the regulatory domains of atypical protein kinase C (PKC) proteins. This assembly is implicated in the formation of normal tight junctions at epithelial cell-cell contacts. Thus, Par6 is a key adaptor that links Cdc42 and atypical PKCs to Par3.
PAR（分区缺陷）蛋白最初是在线虫秀丽隐杆线虫中发现的，对于不对称细胞分裂和极化生长至关重要，而Cdc42介导细胞极性的建立。在这里，我们描述了这两个系统之间意想不到的联系。我们鉴定出了一类哺乳动物Par6蛋白，它们与线虫的PDZ结构域蛋白PAR-6相似。Par6与Cdc42-GTP、多PDZ蛋白PAR-3的人类同源物以及非典型蛋白激酶C（PKC）蛋白的调节结构域形成复合物。这种组装与上皮细胞间接触处正常紧密连接的形成有关。因此，Par6是将Cdc42和非典型PKC与Par3联系起来的关键衔接蛋白。
