Abstract: Objective To explore the effects of ADAM10 in craniofacial intramembranous ossification of mice. Methods The expression pattern of ADAM10 in mice mandibular was detected by immunofluorescence assay and western blot. Cre-loxp technique was used to detect the function of ADAM10 in intramembranous ossification areas during craniomaxillofacial development. ADAM10 conditional knock-out mice was evaluated by X-ray and von Kossa staining. The cell proliferation, apoptosis and osteoblast differentiation were detected by immunofluorescence assay. Results Immunofluorescence assay revealed that ADAM10 was primarily distributed in the maxillary and mandibular skeletal genesis zones. ADAM10 was abundantly expressed from E14.5 to postnatal day 7 (P7) and was significantly decreased during adulthood. On E15.5, the ADAM10 cKO mice exhibited a shorter snout, flatter posterior skull and smaller maxilla and mandible, compared with the control littermates. The X-ray examination and von Kossa staining shown that the ADAM10 cKO embryos exhibited significantly reduced mineral bone deposition in the maxilla and mandible. Immunofluorescence shown that cell proliferation, apoptosis and osteoblast differentiation were impaired in ADAM10 cKO mice. Conclusion ADAM10, widely expressed in osteogenesis area of mice, can affect the intramembranous bone formation by regulating cell proliferation, differentiation and apoptosis.

Key words: ADAM10, Maxillofacial bone, Intramembranous bone formation