The ciliary protein C2cd3 is required for mandibular musculoskeletal tissue patterning

Area of Science:

• Developmental Biology
• Craniofacial Development
• Cell Signaling

Background:

• The mandible's structural integrity relies on precise patterning of bone, cartilage, and tendon.
• Cranial neural crest cells (CNCCs) are multipotent progenitors for most mandibular tissues.
• Mechanisms governing CNCC differentiation into specific mandibular tissues are not fully understood.

Purpose of the Study:

• Investigate the mechanisms controlling mandibular musculoskeletal tissue patterning.
• Identify signaling pathways involved in cranial neural crest cell differentiation within the mandible.
• Understand the role of cellular signaling in craniofacial skeletal development.

Main Methods:

• Utilized the avian talpid2 (ta2) mutant model exhibiting facial malformations.
• Analyzed ectopic epithelial Bone Morphogenetic Protein (BMP) signaling domains in the ta2 mandibular prominence.
• Validated findings using conditional murine models.
• Examined the expression of SOX9+ cartilage precursors.

Main Results:

• Identified an ectopic BMP signaling domain in the ta2 mutant mandibular prominence.
• Observed a correlation between the ectopic BMP domain and expanded SOX9+ cartilage precursors.
• Demonstrated conserved mechanisms in murine models.
• Provided evidence for cilia's role in defining epithelial signaling centers.

Conclusions:

• Cilia are essential for establishing epithelial signaling centers that guide CNCC-derived mesenchyme patterning.
• Ectopic BMP signaling can lead to aberrant cartilage formation.
• The study elucidates an evolutionarily conserved mechanism for craniofacial musculoskeletal development.