Identification of multipotent progenitors in the embryonic mouse kidney by a novel colony-forming assay.
Renal stem or progenitor cells with a multilineage differentiation potential remain to be isolated, and the differentiation mechanism of these cell types in kidney development or regeneration processes is unknown. In an attempt to resolve this issue, we set up an in vitro culture system using NIH3T3 cells stably expressing Wnt4 (3T3Wnt4) as a feeder layer, in which a single renal progenitor in the metanephric mesenchyme forms colonies consisting of several types of epithelial cells that exist in glomeruli and renal tubules. We found that only cells strongly expressing Sall1 (Sall1-GFP(high) cells), a zinc-finger nuclear factor essential for kidney development, form colonies, and that they reconstitute a three-dimensional kidney structure in an organ culture setting. We also found that Rac- and JNK-dependent planar cell polarity (PCP) pathways downstream of Wnt4 positively regulate the colony size, and that the JNK pathway is also involved in mesenchymal-to-epithelial transformation of colony-forming progenitors. Thus our colony-forming assay, which identifies multipotent progenitors in the embryonic mouse kidney, can be used for examining mechanisms of renal progenitor differentiation.
Osafune
Kenji
K
Division of Stem Cell Regulation, The Institute of Medical Science, The University of Tokyo, Tokyo 108-8639, Japan.
Takasato
Minoru
M
Kispert
Andreas
A
Asashima
Makoto
M
Nishinakamura
Ryuichi
R
D000818:Animals; D002454:Cell Differentiation / Q000502:physiology*; D003114:Colony-Forming Units Assay; D017931:DNA Primers; D005434:Flow Cytometry; D049452:Green Fluorescent Proteins; D007150:Immunohistochemistry; D007668:Kidney / Q000166:cytology / Q000196:embryology*; D051379:Mice; D039902:Multipotent Stem Cells / Q000166:cytology*; D041681:NIH 3T3 Cells; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000502:physiology*; D014157:Transcription Factors / Q000378:metabolism; D051153:Wnt Proteins / Q000378:metabolism; D060528:Wnt4 Protein
D017931:DNA Primers; D011518:Proto-Oncogene Proteins; C491254:Sall1 protein, mouse; D014157:Transcription Factors; D051153:Wnt Proteins; D060528:Wnt4 Protein; C555582:Wnt4 protein, mouse; D049452:Green Fluorescent Proteins