Characterization of Wnt gene expression in developing and postnatal hair follicles and identification of Wnt5a as a target of Sonic hedgehog in hair follicle morphogenesis.
Mutations in WNT effector genes perturb hair follicle morphogenesis, suggesting key roles for WNT proteins in this process. We show that expression of Wnts 10b and 10a is upregulated in placodes at the onset of follicle morphogenesis and in postnatal hair follicles beginning a new cycle of hair growth. The expression of additional Wnt genes is observed in follicles at later stages of differentiation. Among these, we find that Wnt5a is expressed in the developing dermal condensate of wild type but not Sonic hedgehog (Shh)-null embryos, indicating that Wnt5a is a target of SHH in hair follicle morphogenesis. These results identify candidates for several key follicular signals and suggest that WNT and SHH signaling pathways interact to regulate hair follicle morphogenesis.
Reddy
S
S
Departments of Dermatology and Cell and Developmental Biology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA.
Andl
T
T
Bagasra
A
A
Lu
M M
MM
Epstein
D J
DJ
Morrisey
E E
EE
Millar
S E
SE
D000818:Animals; D004627:Embryonic Induction; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D018859:Hair Follicle / Q000166:cytology / Q000196:embryology / Q000254:growth & development / Q000378:metabolism*; D053823:Hedgehog Proteins; D017403:In Situ Hybridization; D051379:Mice; D009024:Morphogenesis; D009154:Mutation; D009419:Nerve Tissue Proteins; D011518:Proto-Oncogene Proteins / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D012867:Skin / Q000196:embryology / Q000378:metabolism; D015534:Trans-Activators / Q000235:genetics* / Q000378:metabolism; D015854:Up-Regulation; D051153:Wnt Proteins; D000071818:Wnt-5a Protein
D053823:Hedgehog Proteins; D009419:Nerve Tissue Proteins; D011518:Proto-Oncogene Proteins; D015534:Trans-Activators; D051153:Wnt Proteins; D000071818:Wnt-5a Protein; C484143:Wnt10a protein, mouse; C438615:Wnt5a protein, mouse