Nishinakamura R
Division of Integrative Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University, 2-2-1 Honjo, Kumamoto, Japan.
Kidney Int. 2008 Apr;73(8):913-7. doi: 10.1038/sj.ki.5002784. Epub 2008 Jan 16.
The mammalian kidney, the metanephros, is formed by a reciprocally inductive interaction between two precursor tissues, the metanephric mesenchyme and the ureteric bud. The ureteric bud induces the metanephric mesenchyme to differentiate into the epithelia of glomeruli and renal tubules. Multipotent renal progenitors that form colonies upon Wnt4 stimulation and strongly express Sall1 exist in the metanephric mesenchyme; these cells can partially reconstitute a three-dimensional structure in an organ culture setting. Six2 maintains this mesenchymal progenitor population by opposing Wnt4-mediated epithelialization. Upon epithelial tube formation, Notch2 is required for the differentiation of proximal nephron structures (podocyte and proximal tubules). In addition, the induction methods of the intermediate mesoderm, the precursor of the metanephric mesenchyme, begin to be elucidated. If derivation of metanephric mesenchyme becomes possible, we will be closer to the generation and manipulation of multiple cell lineages in the kidney.
哺乳动物的肾脏，即后肾，由两个前体组织——后肾间充质和输尿管芽之间相互诱导的相互作用形成。输尿管芽诱导后肾间充质分化为肾小球和肾小管的上皮细胞。后肾间充质中存在多能肾祖细胞，这些细胞在Wnt4刺激下形成集落并强烈表达Sall1；这些细胞能够在器官培养环境中部分重建三维结构。Six2通过对抗Wnt4介导的上皮化来维持这种间充质祖细胞群体。在上皮管形成时，Notch2是近端肾单位结构（足细胞和近端小管）分化所必需的。此外，后肾间充质的前体——中间中胚层的诱导方法也开始得到阐明。如果后肾间充质的衍生成为可能，我们将更接近肾脏中多种细胞谱系的生成和操控。
