Dlx genes integrate positive and negative signals during feather bud development

Area of Science:

• Developmental Biology
• Molecular Biology
• Genetics

Background:

• Feather bud and interbud tissue formation in embryonic chicken skin relies on epidermal-dermal interactions.
• Fibroblast growth factors (FGF) and bone morphogenetic proteins (BMP) are known signaling molecules directing feather patterning.
• The transcription factors mediating these signals remain largely unidentified.

Purpose of the Study:

• To investigate the role of DLX transcription factors in mediating feather patterning signals.
• To determine if DLX factors are downstream effectors of FGF and BMP signaling in feather development.

Main Methods:

• Analysis of DLX gene expression in embryonic chick skin during feather development.
• Ectopic activation of BMP and FGF signaling to observe DLX expression changes.
• Misexpression studies of DLX genes in chick skin to assess effects on feather development.

Main Results:

• DLX transcription factors are expressed in both dermis and epidermis of developing feather buds.
• BMP and FGF signaling induce DLX expression in embryonic chick skin.
• DLX misexpression results in feather loss and fusion, indicating both positive and negative regulatory roles.
• DLX regulates NCAM and tenascin expression, crucial for feather bud initiation and morphogenesis.

Conclusions:

• DLX transcription factors act as crucial mediators integrating feather patterning signals.
• DLX proteins transduce signals to downstream effector molecules, influencing feather development and morphogenesis.
• These findings elucidate the molecular mechanisms underlying feather pattern formation.