Tassin M T, Beziau A, Gubler M C, Boyer B
Laboratoire de Néphrologie Pédiatrique, INSERM U192, Hôpital Necker Enfants Malades, Paris, France.
Int J Dev Biol. 1994 Mar;38(1):45-54.
Epithelial glomerular cells differentiate from mesenchymal cells of the metanephrogenic blastema. During the first stages of glomerulogenesis, the cells acquire the morphological features of epithelial cells. Then, podocytes lose these characteristics at the maturing glomerular stage. We have studied the molecules associated with junctional complexes during glomerular differentiation in human and pig fetal kidneys. We show for the first time the expression of P-cadherin in renal cells. Epithelial cells of ureteral buds and ampullae display all the molecules associated with junctional complexes and coexpress E- and P-cadherin. However, P-cadherin, plakoglobin and vinculin are the only markers detected in future glomerular cells. We have established a spatiotemporal correlation between the time of appearance and disappearance of junctional complexes as previously described (Saxén and Wartiovaara, Int. J. Cancer 1:271-290, 1966; Saxén et al., Adv. Morphog. 7:251-293, 1968; Reeves et al., Lab. Invest. 39:90-100, 1978), and the expression of their associated molecules. Epithelial cells with stable, typical junctional complexes strongly express the molecules associated with junctions, whereas cells endowed with transient, atypical junctional complexes express low amounts of components associated with junctions. These observations suggest a correlation between the level of expression of these components and an authentic, stable epithelial phenotype.
肾小球上皮细胞由后肾胚基的间充质细胞分化而来。在肾小球发生的最初阶段，这些细胞获得上皮细胞的形态特征。然后，足细胞在成熟的肾小球阶段失去这些特征。我们研究了人与猪胎儿肾脏肾小球分化过程中与连接复合体相关的分子。我们首次展示了P-钙黏蛋白在肾细胞中的表达。输尿管芽和壶腹的上皮细胞显示出与连接复合体相关的所有分子，并共同表达E-钙黏蛋白和P-钙黏蛋白。然而，P-钙黏蛋白、桥粒芯蛋白和纽蛋白是在未来肾小球细胞中检测到的唯一标志物。我们已经建立了连接复合体出现和消失的时间（如先前所述，Saxén和Wartiovaara，《国际癌症杂志》1:271-290，1966年；Saxén等人，《形态学进展》7:251-293，1968年；Reeves等人，《实验室研究》39:90-100，1978年）与其相关分子表达之间的时空相关性。具有稳定、典型连接复合体的上皮细胞强烈表达与连接相关的分子，而具有短暂、非典型连接复合体的细胞表达与连接相关的低水平成分。这些观察结果表明这些成分的表达水平与真实、稳定的上皮表型之间存在相关性。
