Phospholipid Phosphatase-Related Protein Type 1 (PLPPR1) is a six-transmembrane protein that belongs to the family of plasticity-related gene proteins, which is a novel brain-specific subclass of the lipid phosphate phosphatase superfamily. PLPPR1-5 have prominent roles in synapse formation and axonal pathfinding. We found that PLPPR1 overexpression in the mouse neuroblastoma cell line (Neuro2a) results in increase in cell adhesion and reduced cell migration. During migration, these cells leave behind long fibrous looking extensions of the plasma membrane causing a peculiar phenotype. Cells expressing PLPPR1 showed decreased actin turnover and decreased disassembly of focal adhesions. PLPPR1 also reduced active Rac1, and expressing dominant negative Rac1 produced a similar phenotype to overexpression of PLPPR1. The PLPPR1-induced phenotype of long fibers was reversed by introducing constitutively active Rac1. In summary, we show that PLPPR1 decreases active Rac1 levels that leads to cascade of events which increases cell adhesion.

中文翻译：

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磷脂磷酸酶相关1（PLPPR1）通过调节Rac1活性来增加细胞粘附。

磷脂磷酸酶相关蛋白1（PLPPR1）是一种六跨膜蛋白，属于可塑性相关基因蛋白家族，是脂类磷酸酶超家族的新型脑特异性亚类。PLPPR1-5在突触形成和轴突寻路中具有重要作用。我们发现小鼠神经母细胞瘤细胞系（Neuro2a）中的PLPPR1过表达导致细胞粘附增加和细胞迁移减少。在迁移过程中，这些细胞留下质膜的长纤维状延伸，造成特殊的表型。表达PLPPR1的细胞显示肌动蛋白周转减少和粘着斑的拆卸减少。PLPPR1还降低了活性Rac1，并且表达显性负性Rac1产生了与PLPPR1过表达相似的表型。通过引入组成型活性Rac1，可以逆转PLPPR1诱导的长纤维表型。总而言之，我们表明PLPPR1降低了活性Rac1的水平，从而导致级联事件增加了细胞的粘附。