Most, if not all, cell types and tissues display several aspects of polarization. In addition to the ubiquitous epithelial cell polarity along the apical-basolateral axis, many epithelial tissues and organs are also polarized within the plane of the epithelium. This is generally referred to as planar cell polarity (PCP; or historically, tissue polarity). Genetic screens in Drosophila pioneered the discovery of core PCP factors, and subsequent work in vertebrates has established that the respective pathways are evolutionarily conserved. PCP is not restricted only to epithelial tissues but is also found in mesenchymal cells, where it can regulate cell migration and cell intercalation. Moreover, particularly in vertebrates, the conserved core PCP signaling factors have recently been found to be associated with the orientation or formation of cilia. This review discusses new developments in the molecular understanding of PCP establishment in Drosophila and vertebrates; these developments are integrated with new evidence that links PCP signaling to human disease.

中文翻译：

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平面细胞极性信号：从苍蝇发育到人类疾病。

大多数（如果不是全部）细胞类型和组织都表现出极化的几个方面。除了沿顶端-基底外侧轴无处不在的上皮细胞极性外，许多上皮组织和器官也在上皮平面内极化。这通常称为平面细胞极性（PCP；或历史上的组织极性）。果蝇中的遗传筛选率先发现了核心 PCP 因子，随后在脊椎动物中的工作已确定各自的途径在进化上是保守的。PCP 不仅限于上皮组织，还存在于间充质细胞中，它可以调节细胞迁移和细胞嵌入。此外，特别是在脊椎动物中，最近发现保守的核心 PCP 信号因子与纤毛的方向或形成有关。本综述讨论了对果蝇和脊椎动物中 PCP 建立的分子理解的新进展；这些发展与将 PCP 信号与人类疾病联系起来的新证据相结合。