Hirota S, Takaoka K, Hashimoto J, Nakase T, Takemura T, Morii E, Fukuyama A, Morihana K, Kitamura Y, Nomura S
Department of Pathology, Osaka University Medical School, Suita, Japan.
Cell Tissue Res. 1994 Jul;277(1):27-32. doi: 10.1007/BF00303077.
To determine whether a system of ectopic bone formation induced by osteosarcoma-derived bone-inducing substance (bone morphogenetic protein-4) can be used as a model of developing bone at the molecular level, we studied the expression of bone-related protein mRNAs in the process of ectopic bone formation using non-radioisotopic in situ hybridization. Osteonectin mRNA was detected in fibroblast-like cells, which are similar to periosteal cells from the early to middle stages of bone development. The proportion of osteonectin mRNA-expressing cells was greater than that of osteopontin mRNA-expressing cells in hypertrophic chondrocytes and osteoblast-like cells. In contrast, osteopontin mRNA was localized in a limited population of hypertrophic chondrocytes, a single layer of osteoblast-like cells adjacent to the bone trabeculae in the middle stage of bone formation, and in a limited subset of osteocytes in the late stage. A strong osteocalcin mRNA signal was detected in osteoblast-like cells from the middle to late stages and in a limited subset of osteocytes in the late stage of bone development. Since the sequential gene expression pattern of bone-related proteins in the present system is comparable to that in embryonic osteogenesis, this system may be useful as a model for studying gene expression in osteogenesis.
为了确定由骨肉瘤衍生的骨诱导物质（骨形态发生蛋白-4）诱导的异位骨形成系统是否可以作为分子水平上骨发育的模型，我们使用非放射性原位杂交研究了异位骨形成过程中骨相关蛋白mRNA的表达。骨连接蛋白mRNA在成纤维细胞样细胞中被检测到，这些细胞在骨发育的早期到中期类似于骨膜细胞。在肥大软骨细胞和成骨细胞样细胞中，表达骨连接蛋白mRNA的细胞比例高于表达骨桥蛋白mRNA的细胞比例。相反，骨桥蛋白mRNA定位于有限数量的肥大软骨细胞、骨形成中期与骨小梁相邻的单层成骨细胞样细胞以及骨发育后期有限的骨细胞亚群中。在骨发育的中期到后期的成骨细胞样细胞以及骨发育后期有限的骨细胞亚群中检测到强烈的骨钙素mRNA信号。由于本系统中骨相关蛋白的顺序基因表达模式与胚胎骨生成中的模式相当，该系统可能作为研究骨生成中基因表达的模型有用。
