Overexpression of Dlx2 leads to postnatal condyle degradation.
Distal-less homeobox 2 (Dlx2), a member of the Dlx family of transcription factors, is important for the development of craniofacial tissues. Previous studies based on knock‑out mutant mice revealed that Dlx2 primarily disturbed the development of tissues from maxillary arch. The present study used a transgenic mouse model to specifically overexpress Dlx2 in neural crest cells in order to investigate the role of Dlx2 overexpression in post‑natal condyle in mice. The model was constructed and the phenotype observed using gross observation, micro‑CT scan and histological examination. The model determined that overexpression of Dlx2 may lead to postnatal condyle malformation, subchondral bone degradation and irregular histological structure of the condylar cartilage. In addition, the expression of osteocalcin in the condyle region was markedly downregulated, whereas expression of msh homeobox 2 was upregulated. The results of the present study suggest that Dlx2 overexpression in cranial neural crest cells would disrupt the development of post‑natal condyle, which demonstrates that the expression level and the spatiotemporal expression patterns of Dlx2 may be important in regulating the development of post-natal condyle in mice, and also offered a possible temporal‑mandibular joint osteoarthritis model animal for future studies.
Department of Oral and Cranio‑Maxillofacial Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai 200011, P.R. China.
Jiewen
J
Dai
Department of Oral and Cranio‑Maxillofacial Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai 200011, P.R. China.
Jiawen
J
Si
Department of Oral and Cranio‑Maxillofacial Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai 200011, P.R. China.
Xiaofang
X
Zhu
Department of Oral and Cranio‑Maxillofacial Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai 200011, P.R. China.
Lei
L
Zhang
Department of Oral and Cranio‑Maxillofacial Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai 200011, P.R. China.
Dandan
D
Wu
Department of Oral and Cranio‑Maxillofacial Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai 200011, P.R. China.
Jingting
J
Lu
Department of Oral and Cranio‑Maxillofacial Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai 200011, P.R. China.
Ningjuan
N
Ouyang
Department of Oral and Cranio‑Maxillofacial Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai 200011, P.R. China.
Xudong
X
Wang
Department of Oral and Cranio‑Maxillofacial Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology, Shanghai 200011, P.R. China.
Guofang
G
Shen
D000818:Animals; D002356:Cartilage / Q000473:pathology; D015870:Gene Expression; D023061:Gene Order; D018390:Gene Targeting; D018398:Homeodomain Proteins / Q000235:genetics*; D007150:Immunohistochemistry; D008335:Mandibular Condyle / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000473:pathology*; D051379:Mice; D008822:Mice, Transgenic; D010641:Phenotype; D014157:Transcription Factors / Q000235:genetics*; D055114:X-Ray Microtomography
C088334:Distal-less homeobox proteins; D018398:Homeodomain Proteins; D014157:Transcription Factors