Send to

Choose Destination
See comment in PubMed Commons below
Stem Cell Reports. 2013 Dec 12;1(6):604-19. doi: 10.1016/j.stemcr.2013.10.013. eCollection 2013.

Combined KIT and FGFR2b signaling regulates epithelial progenitor expansion during organogenesis.

Author information

Matrix and Morphogenesis Section, Laboratory of Cell and Developmental Biology, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892, USA.
Department of Orthopedics & Rehabilitation, Yale University School of Medicine, New Haven, CT 06520, USA.
Developmental Mechanisms Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892, USA.
Head & Neck Multidisciplinary Clinic, Helen F. Graham Cancer Center of Christiana Care, Newark, DE 19713, USA.


Organ formation and regeneration require epithelial progenitor expansion to engineer, maintain, and repair the branched tissue architecture. Identifying the mechanisms that control progenitor expansion will inform therapeutic organ (re)generation. Here, we discover that combined KIT and fibroblast growth factor receptor 2b (FGFR2b) signaling specifically increases distal progenitor expansion during salivary gland organogenesis. FGFR2b signaling upregulates the epithelial KIT pathway so that combined KIT/FGFR2b signaling, via separate AKT and mitogen-activated protein kinase (MAPK) pathways, amplifies FGFR2b-dependent transcription. Combined KIT/FGFR2b signaling selectively expands the number of KIT+K14+SOX10+ distal progenitors, and a genetic loss of KIT signaling depletes the distal progenitors but also unexpectedly depletes the K5+ proximal progenitors. This occurs because the distal progenitors produce neurotrophic factors that support gland innervation, which maintains the proximal progenitors. Furthermore, a rare population of KIT+FGFR2b+ cells is present in adult glands, in which KIT signaling also regulates epithelial-neuronal communication during homeostasis. Our findings provide a framework to direct regeneration of branched epithelial organs.

[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science Icon for PubMed Central
    Loading ...
    Support Center