Klein G, Langegger M, Timpl R, Ekblom P
Friedrich-Miescher-Laboratorium, Max-Planck-Gesellschaft, Tübingen, Federal Republic of Germany.
Cell. 1988 Oct 21;55(2):331-41. doi: 10.1016/0092-8674(88)90056-6.
Kidney organ culture was used to study the conversion of embryonic mesenchymal cells into a polarized, differentiated kidney epithelium. We examined the expression of laminin, a basement membrane glycoprotein, during this conversion. The B chains of laminin were constitutively expressed, whereas the appearance of the A chain of laminin was dependent on embryonic induction and coincided with the onset of cell polarization. Antisera against the carboxy-terminal end of laminin inhibited polarization but did not affect the developmental events that precede polarization. Antisera against N-terminal parts of laminin failed to inhibit morphogenesis. Since the fragments at the carboxy-terminal end contain parts of the A chain, we suggest that the appearance of this chain is fundamental for initiation of cell polarity.
肾脏器官培养被用于研究胚胎间充质细胞向极化、分化的肾上皮细胞的转化过程。我们检测了层粘连蛋白（一种基底膜糖蛋白）在这一转化过程中的表达情况。层粘连蛋白的B链呈组成性表达，而层粘连蛋白A链的出现依赖于胚胎诱导，且与细胞极化的开始相一致。针对层粘连蛋白羧基末端的抗血清抑制了极化，但不影响极化之前的发育事件。针对层粘连蛋白N端部分的抗血清未能抑制形态发生。由于羧基末端的片段包含A链的部分区域，我们认为该链的出现对于细胞极性的启动至关重要。
