| First Author | Choi KY | Year | 2002 |
| Journal | Exp Mol Med | Volume | 34 |
| Issue | 6 | Pages | 426-33 |
| PubMed ID | 12526084 | Mgi Jnum | J:327334 |
| Mgi Id | MGI:7329848 | Doi | 10.1038/emm.2002.60 |
| Citation | Choi KY, et al. (2002) Spatio-temporal expression patterns of Runx2 isoforms in early skeletogenesis. Exp Mol Med 34(6):426-33 |
| abstractText | Skeletogenesis occurs through either intramembranous or endochondral ossification. In addition, some parts of the skeletal components maintain their cartilaginous characteristics throughout life without mineralization. Runx2 is known to be a pivotal transcription factor for all skeletogenic processes. In this study, we examined the expression patterns of two major isoforms of Runx2 in early skeletogenesis. During intramembranous bone formation, Runx2-type I (Runx2-I) was widely expressed in osteoprogenitor cells and active osteoblasts, while Runx2-type II (Runx2-II) expression was stringently restricted to cells lining mineralized bones. Cells in permanent cartilage expressed collagen type II (Col-II) but never expressed Runx2 or Col-X. These permanent cartilages were well circumscribed by Runx2-I positive cells, in which Runx2-II was negative. In endochondral bone formation, Runx2 expression temporarily disappeared in Col-II-positive proliferating chondrocytes, but a secondary surge of Runx2-I expression occurred in the prehypertrophic zone before the mineralization of cartilage. Collectively, both Runx2 isoforms showed very similar expression patterns in active bone forming areas; however, Runx2-I has an exclusive role in the early commitment stage of intramembranous or endochondral bone forming processes or in cells surrounding permanent cartilage. |
