title: Paraxial mesoderm contributes stromal cells to the developing kidney.
abstract: The development of most, if not all, tubular organs is dependent on signaling between epithelial and stromal progenitor populations. Most often, these lineages derive from different germ layers that are specified during gastrulation, well in advance of organ condensation. Thus, one of the first stages of organogenesis is the integration of distinct progenitor populations into a single embryonic rudiment. In contrast, the stromal and epithelial lineages controlling renal development are both believed to derive from the intermediate mesoderm and to be specified as the kidney develops. In this study we directly analyzed the lineage of renal epithelia and stroma in the developing chick embryo using two independent fate mapping techniques. Results of these experiments confirm the hypothesis that nephron epithelia derive from the intermediate mesoderm. Most importantly, we discovered that large populations of renal stroma originate in the paraxial mesoderm. Collectively, these studies suggest that the signals that subdivide mesoderm into intermediate and paraxial domains may play a role in specifying nephron epithelia and a renal stromal lineage. In addition, these fate mapping data indicate that renal development, like the development of all other tubular organs, is dependent on the integration of progenitors from different embryonic tissues into a single rudiment.
authors.affiliation: Weill Medical College of Cornell University, Department of Physiology and Biophysics, 1300 York Ave, New York, NY 10065, USA.
authors.forename: Richard
authors.initials: R
authors.lastname: Guillaume
authors.forename: Michel
authors.initials: M
authors.lastname: Bressan
authors.forename: Doris
authors.initials: D
authors.lastname: Herzlinger
mesh_terms: D000818:Animals; D019521:Body Patterning; D002642:Chick Embryo; D007668:Kidney / Q000196:embryology*; D007763:Lac Operon; D008648:Mesoderm; D017154:Stromal Cells / Q000166:cytology*