Table 1.
Molecular and clinical features of the four CCD patients in this study.
Fig 1.
Clinical and radiological findings in the family members of Patient 1.
(A) Pedigree of Patient 1. The arrow indicates the proband. (B, C) Clinical facial photographs of the proband. (D-G) Radiographs of the proband. Anteroposterior (D), lateral (E), Chest (F), and panoramic (G) radiograph of the proband. (H-K) Radiographs of the proband's mother. Anteroposterior (H), lateral (I), chest (J), and panoramic (K) radiograph of the proband's mother.
Fig 2.
Radiographic manifestations of Patient 2, Patient 3 and Patient 4.
(A-C) Chest radiographs of Patient 2 (A), Patient 3 (B), and patient 4 (C). (D-F) Clinical radiographs of Patient 4. Anteroposterior (D), lateral (E), and panoramic radiographs (F) of Patient 4.
Fig 3.
Mutation analysis of RUNX2 gene for the four CCD patients.
(A) Identification of four different heterozygous mutations in RUNX2 gene from four CCD patients. For each mutation, the mutated sequence (upper panel) and control sequence (lower panel) were shown respectively. (B) Schematic presentation of the RUNX2 gene structure and annotated mutations identified in our cases. The bar depicts the structure of human RUNX2 protein. Q/A, Glutamine-alanine repeat domain; RHD, DNA-binding Runt homology domain; NLS, nuclear localization signal; PST, proline/serine/threonine rich region; NMST, unclear matrix targeting sequence. (C) Partial amino acid sequences alignment in RUNX2 protein among nine species. The positions of the mutated amino acid in our study are indicated using black boxes.
Table 2.
Predicted damaging effects of missense mutations in RUNX2 gene.
Fig 4.
Functional analyses of RUNX2 mutations on protein subcellular localization and transactivation of down-stream target gene.
(A) Subcellular localization of wild-type and mutant RUNX2-GFP fusion proteins in MC3T3-E1 cells. Confocal micrographs showed the intracellular distribution of control GFP, wild-type RUNX2-GFP, Q67X, L113R, and R186T mutant proteins. (B) Transactivation activity of mutant RUNX2 proteins on osteocalcin promoter. MC3T3-E1 cells were co-transfected with a control pCMV5 vector or a vector that expressed wild-type or mutant RUNX2 protein, together with osteocalcin reporter plasmid. Renilla luciferase reporter was used as the internal control. Bars represent firefly/Renilla luciferase ratios for different constructs. *p < 0.05 (compared with wild-type control).