MOLECULAR-BASIS OF KIDNEY DEVELOPMENT

The first step of renal development is characterized by the invasion o f a mesenchymal tissue, the metanephric blastema, by an epithelial str ucture, the ureter bud. Reciprocal inductive interactions between thes e two tissues, involving the sequential activation of genes that begin to be identified, are required for the successive stages of kidney mo rphogenesis. Recent technological advances such as gene targeting and improvement of organotypic culture have revealed the role of these gen es and of several essential factors in kidney development. This review will focus on the genes which govern renal organogenesis, with specia l emphasis on those coding transcription and diffusible factors.