Department of Physiology, Neuroscience and Development, University of Cambridge, Cambridge, UK.
The Gurdon Institute, University of Cambridge, Cambridge, UK.
Nat Rev Mol Cell Biol. 2022 Aug;23(8):559-577. doi: 10.1038/s41580-022-00465-y. Epub 2022 Apr 19.
Epithelial cells are the most common cell type in all animals, forming the sheets and tubes that compose most organs and tissues. Apical-basal polarity is essential for epithelial cell form and function, as it determines the localization of the adhesion molecules that hold the cells together laterally and the occluding junctions that act as barriers to paracellular diffusion. Polarity must also target the secretion of specific cargoes to the apical, lateral or basal membranes and organize the cytoskeleton and internal architecture of the cell. Apical-basal polarity in many cells is established by conserved polarity factors that define the apical (Crumbs, Stardust/PALS1, aPKC, PAR-6 and CDC42), junctional (PAR-3) and lateral (Scribble, DLG, LGL, Yurt and RhoGAP19D) domains, although recent evidence indicates that not all epithelia polarize by the same mechanism. Research has begun to reveal the dynamic interactions between polarity factors and how they contribute to polarity establishment and maintenance. Elucidating these mechanisms is essential to better understand the roles of apical-basal polarity in morphogenesis and how defects in polarity contribute to diseases such as cancer.
上皮细胞是所有动物中最常见的细胞类型，形成构成大多数器官和组织的薄片和管。上皮细胞的形态和功能需要顶端-基底极性，因为它决定了将细胞侧向连接在一起的粘附分子的定位，以及作为旁细胞扩散屏障的紧密连接。极性还必须将特定货物的分泌靶向到顶、侧或基底膜，并组织细胞的细胞骨架和内部结构。许多细胞中的顶端-基底极性是通过保守的极性因子建立的，这些极性因子定义了顶端（Crumbs、Stardust/PALS1、aPKC、PAR-6 和 CDC42）、连接（PAR-3）和侧部（Scribble、DLG、LGL、Yurt 和 RhoGAP19D）区域，尽管最近的证据表明并非所有上皮细胞都通过相同的机制极化。研究已经开始揭示极性因子之间的动态相互作用，以及它们如何有助于极性的建立和维持。阐明这些机制对于更好地理解顶端-基底极性在形态发生中的作用以及极性缺陷如何导致癌症等疾病至关重要。
