Hair follicle development is initiated by reciprocal molecular interactions between the placode-forming epithelium and the underlying mesenchyme. Cell fate transformation in dermal fibroblasts generates a cell niche for placode induction by activation of signaling pathways WNT, EDA, and FGF in the epithelium. These successive paracrine epithelial signals initiate dermal condensation in the underlying mesenchyme. Although epithelial signaling from the placode to mesenchyme is better described, little is known about primary mesenchymal signals resulting in placode induction. Using genetic approach in mice, we show that Meis2 expression in cells derived from the neural crest is critical for whisker formation and also for branching of trigeminal nerves. While whisker formation is independent of the trigeminal sensory innervation, MEIS2 in mesenchymal dermal cells orchestrates the initial steps of epithelial placode formation and subsequent dermal condensation. MEIS2 regulates the expression of transcription factor Foxd1, which is typical of pre-dermal condensation. However, deletion of Foxd1 does not affect whisker development. Overall, our data suggest an early role of mesenchymal MEIS2 during whisker formation and provide evidence that whiskers can normally develop in the absence of sensory innervation or Foxd1 expression.

• Klíčová slova
• Foxd1, Meis2, Sox2, cranial nerves, developmental biology, hair follicle placode, mouse, whisker follicle,
• MeSH
• crista neuralis MeSH
• forkhead transkripční faktory metabolismus   genetika   MeSH
• homeodoménové proteiny * metabolismus   genetika   MeSH
• mezoderm * metabolismus   MeSH
• myši MeSH
• nervus trigeminus * MeSH
• vibrissae * inervace   růst a vývoj   embryologie   MeSH
• vývojová regulace genové exprese MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• forkhead transkripční faktory MeSH
• Foxd1 protein, mouse MeSH Prohlížeč
• homeodoménové proteiny * MeSH