Al-Awqati Qais, Vijayakumar Soundaraparan, Takito Jiro
Department of Medicine and Physiology, College of Physicians and Surgeons of Columbia University, 630 W. 168th St., New York, NY 10032, USA.
Biol Chem. 2003 Sep;384(9):1255-8. doi: 10.1515/BC.2003.138.
All epithelia form sheets of cells connected by tight and adherent junctions and exhibit polarized distribution of membrane proteins and lipids. During their development, epithelia progress from this 'generic' phenotype to terminally differentiated states characterized by the development of apical structures such as microvilli, apical endocytosis and regulated exocytosis as well as characteristic cell shapes. We have identified an extracellular matrix protein, hensin, which when polymerized into a fiber induces the terminal differentiation of renal cells. Hensin is expressed in most epithelia where it exists in tissue-specific alternately spliced forms. Many epithelial tumors have deletions in the human ortholog of hensin. We propose that hensin mediates terminal differentiation of these epithelia.
所有上皮细胞都形成由紧密连接和黏附连接相连的细胞片层，并呈现膜蛋白和脂质的极性分布。在其发育过程中，上皮细胞从这种“一般”表型发展为终末分化状态，其特征是顶端结构的发育，如微绒毛、顶端内吞作用和调节性胞吐作用以及特征性的细胞形状。我们鉴定出一种细胞外基质蛋白，即hensin，当其聚合成纤维时可诱导肾细胞的终末分化。Hensin在大多数上皮细胞中表达，在这些细胞中它以组织特异性的可变剪接形式存在。许多上皮肿瘤在hensin的人类直系同源物中存在缺失。我们提出hensin介导这些上皮细胞的终末分化。
