Special Morphological Features at the Interface of the Renal Stem/Progenitor Cell Niche Force to Reinvestigate Transport of Morphogens During Nephron Induction

摘要: Formation of a nephron depends on reciprocal signaling different morphogens between epithelial and mesenchymal cells within the renal stem/progenitor cell niche. Previously, it has been surmised that close proximity exists both involved types are transported them by diffusion. However, actual morphological data illustrate bodies separated striking interface. Special fixation specimens glutaraldehyde (GA) solution including cupromeronic blue, ruthenium red, or tannic acid for electron microscopy depicts interface is not void but filled in extended areas textured extracellular matrix. Surprisingly, projections cross to contact cells. At those sites plasma membranes an connected via tunneling nanotubes. Regarding detected features combination with morphogens, their transport cannot longer be explained solely Instead, sorted according biophysical properties environment. Thus, new working hypothesis good solubility such as glial line-derived neurotrophic factor (GDNF) fibroblast growth factors (FGFs) Morphogens minor bone morphogenetic proteins (BMPs) secreted stored delivery demand illustrated In contrast, poor Wnts along membrane presence intercellular route nanotubes also makes possible all this way.