Gibson Matthew C, Perrimon Norbert
Department of Genetics, Harvard Medical School, 200 Longwood Avenue, Boston MA 02115, USA.
Curr Opin Cell Biol. 2003 Dec;15(6):747-52. doi: 10.1016/j.ceb.2003.10.008.
The structure and function of epithelial sheets generally depend on apicobasal polarization, which is achieved and maintained by linking asymmetrically distributed intercellular junctions to the cytoskeleton of individual cells. Recent studies in both Drosophila and vertebrate epithelia have yielded new insights into the conserved mechanisms by which apicobasal polarity is established and maintained during development. In mature polarized epithelia, apicobasal polarity is important for the establishment of adhesive junctions and the formation of a paracellular diffusion barrier that prevents the movement of solutes across the epithelium. Recent findings show that segregation of ligand and receptor with one on each side of this barrier can be a crucial regulator of cell-cell signaling events.
上皮细胞层的结构和功能通常取决于顶基极化，这是通过将不对称分布的细胞间连接与单个细胞的细胞骨架相连来实现和维持的。最近在果蝇和脊椎动物上皮细胞中的研究，对发育过程中建立和维持顶基极性的保守机制有了新的认识。在成熟的极化上皮细胞中，顶基极性对于建立黏附连接和形成防止溶质跨上皮移动的细胞旁扩散屏障很重要。最近的研究结果表明，配体和受体在这个屏障两侧各一侧的分离可能是细胞间信号传导事件的关键调节因素。
