Mesenchymal cells. Defining a mesenchymal progenitor niche at single-cell resolution.
Most vertebrate organs are composed of epithelium surrounded by support and stromal tissues formed from mesenchyme cells, which are not generally thought to form organized progenitor pools. Here, we use clonal cell labeling with multicolor reporters to characterize individual mesenchymal progenitors in the developing mouse lung. We observe a diversity of mesenchymal progenitor populations with different locations, movements, and lineage boundaries. Airway smooth muscle (ASM) progenitors map exclusively to mesenchyme ahead of budding airways. Progenitors recruited from these tip pools differentiate into ASM around airway stalks; flanking stalk mesenchyme can be induced to form an ASM niche by a lateral bud or by an airway tip plus focal Wnt signal. Thus, mesenchymal progenitors can be organized into localized and carefully controlled domains that rival epithelial progenitor niches in regulatory sophistication.
Howard Hughes Medical Institute and Department of Biochemistry, Stanford University School of Medicine, Stanford, CA 94305-5307, USA.
Maya E
ME
Kumar
Howard Hughes Medical Institute and Department of Biochemistry, Stanford University School of Medicine, Stanford, CA 94305-5307, USA.
Patrick E
PE
Bogard
Howard Hughes Medical Institute and Department of Biochemistry, Stanford University School of Medicine, Stanford, CA 94305-5307, USA.
F Hernán
FH
Espinoza
Department of Genetics, University of Georgia, Athens, GA 30602-2607, USA. Howard Hughes Medical Institute and Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305-5329, USA.
Douglas B
DB
Menke
Howard Hughes Medical Institute and Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305-5329, USA.
David M
DM
Kingsley
Howard Hughes Medical Institute and Department of Biochemistry, Stanford University School of Medicine, Stanford, CA 94305-5307, USA. krasnow@stanford.edu.
Mark A
MA
Krasnow
D000818:Animals; D002454:Cell Differentiation; D019070:Cell Lineage; D002465:Cell Movement; D049109:Cell Proliferation; D058948:Cell Tracking; D002999:Clone Cells; D008168:Lung / Q000166:cytology / Q000254:growth & development*; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000502:physiology*; D051379:Mice; D008822:Mice, Transgenic; D059010:Single-Cell Analysis / Q000379:methods; D055153:Stem Cell Niche / Q000502:physiology*; D060449:Wnt Signaling Pathway