Sequential cell and tissue interactions governing organogenesis of the kidney.

The complex development of the metanephric kidney illustrates the decisive role of sequential morphogenetic interactions of varying type in organogenesis. In this review the following steps were singled out from this continuous, strictly controlled organogenesis: determination of the mesoderm during the blastula stage, induction of pronephric nephrons during gastrulation, guided migration of the pronephric duct, mesenchyme-controlled branching of the ureter, induced aggregation of the mesenchymal cells of the metanephric blastema, homotypically controlled polarization of the cells in the renal vesicle and remodelling of the vesicle into the S-shaped body, guided migration of endothelial cells into the nephric blastema and the glomerular crevice, and the matrix interaction(s) completing the formation of the glomerular basement membrane with dual origin.