Meckel's cartilage midsegment: spatiotemporal dynamics and osteogenic role in mice
Qi Sun1,2, Cheng Li1,2, Lizhu Yin1,2
1Department of Pediatric Dentistry, Stomatology Hospital of Yunnan Province, Kunmming, Yunnan, China.
Cell and Tissue Research
|January 16, 2026
Summary
Meckel's cartilage midsegment undergoes endochondral-like ossification during mouse mandibular development. This process involves specific transcription factors and vascular invasion, clarifying its role in bone formation.
Area of Science:
- Developmental Biology
- Skeletal Biology
- Mammalian Embryology
Background:
- Meckel's cartilage is crucial for mammalian mandible development.
- Its midsegment degrades, but the mechanisms are unclear.
- Understanding this process is key to mandibular development.
Purpose of the Study:
- Investigate spatiotemporal changes in Meckel's cartilage midsegment.
- Determine its potential osteogenic function during mandibular development.
- Elucidate the molecular mechanisms regulating its fate.
Main Methods:
- Used C57BL/6J mice and a tamoxifen-inducible lineage tracing model.
- Performed morphological staining (Alcian Blue, Safranin O, Masson's trichrome).
- Conducted immunofluorescence for Sox9, Runx2, Osterix, and CD31 from E12.5 to P0.
Main Results:
- The anterior midsegment showed endochondral-like ossification with chondrocyte hypertrophy and osteogenic invasion.
- A shift from proliferation to differentiation occurred by E14.5.
- Observed sequential Sox9 → Runx2 → Osterix expression and vascular invasion associated with osteoprogenitors.
Conclusions:
- Meckel's cartilage midsegment undergoes endochondral-like ossification, similar to long bones.
- A Sox9 → Runx2 → Osterix transcriptional cascade and vascularization are involved.
- This clarifies the dynamic ossification of Meckel's cartilage in mandibular development.
Keywords:
Chondro-osteogenic transitionEndochondral ossificationMandibular developmentMeckel’s cartilageVascular invasion
