Expression of matrix proteins during the development of mineralized tissues
Expression of matrix proteins during the development of mineralized tissues
复制标题
DOI：
10.1016/s8756-3282(96)00218-9
复制
发表时间：
1996-10-01
期刊：
影响因子：
4.1
通讯作者：
Wetterwald, A
中科院分区：
文献类型：
--
作者：
Sommer, B;Bickel, M;Wetterwald, A
矿化组织的特定性质由非胶原基质蛋白部分的组成限定，因为这些蛋白质在细胞分化和活化以及矿化过程中起关键作用，所以它们的时间和空间表达受到严格调控。在本研究中，釉质蛋白釉原蛋白和骨基质蛋白骨桥蛋白、骨唾液蛋白、骨钙素、原位杂交检测骨粘连蛋白。选择两种能够观察矿化组织形成的模型，在小鼠跖骨上观察从W日龄胚胎到I日龄小鼠的骨和软骨的发育，该时间涵盖初始骨形成以及矿化软骨和骨的吸收开始的时期，为了研究牙器官、釉质、牙本质和牙骨质的矿化组织中的基因表达，选择年龄范围从16天的胚胎到分娩后14天的发育中的磨牙。在此时间范围内，磨牙从未成熟状态发育成分化的器官，其通过下颌骨长出。在发育中的跖骨中，骨桥蛋白和骨唾液酸蛋白mRNA在矿化开始时在成骨细胞和肥大软骨细胞中检测到。在牙器中，只有成牙骨质细胞表达编码这两种蛋白的转录本;成牙本质细胞和成釉细胞不表达这些基因，成骨细胞和成肥大软骨细胞也表达骨粘连蛋白，而在磨牙中它仅由成牙本质细胞产生，骨钙素在发育中的跖骨中由成骨细胞特异性表达。在牙齿中，成牙本质细胞中检测到骨钙素转录本。最后，釉原蛋白是成釉细胞的特异性产物，因此，在矿化组织的发育过程中，基质蛋白的表达发生顺序和细胞类型限制。编码骨基质蛋白的转录本的表达模式表明，不同的生物学作用取决于表达的时间和部位。
The specific properties of mineralized tissues are defined by the composition of the fraction of the noncollagenous matrix proteins, Because these proteins play a pivotal role in the processes of cell differentiation and activation and of mineralization, their temporal and spatial expression is tightly regulated, Within this study, the expression of the enamel protein amelogenin and of the bone matrix proteins osteopontin, bone sialoprotein, osteocalcin, and osteonectin was investigated by in situ hybridization. Two models that allow observation of the formation of mineralized tissues were chosen, The development of bone and cartilage was observed on murine metatarsals from W-day-old embryos up to I-day-old mice, This time covers the periods of initial bone formation as well as onset of resorption of mineralized cartilage and bone, To study gene expression in the mineralized tissues of the dental organ, enamel, dentin, and cementum, developing molars ranging in age from 16-day-old embryos to 14 days after delivery were chosen, Within this time frame, the molars develop from an immature state to the differentiated organ which erupts through the mandibular bone. In the developing metatarsals, osteopontin and bone sialoprotein mRNAs were detected in osteoblasts and hypertrophic chondrocytes at the onset of mineralization, In the tooth organ, only cementoblasts expressed transcripts encoding the two proteins; odontoblasts and ameloblasts did not express these genes, Osteonectin was expressed by osteoblasts and hypertrophic chondrocytes as well, whereas in the molars it was produced exclusively by odontoblasts, Osteocalcin was expressed specifically by osteoblasts in the developing metatarsals. In tooth, osteocalcin transcripts were detected in odontoblasts. Finally, amelogenin was a specific product of ameloblasts, Thus, a sequential and cell type-restricted expression of matrix proteins takes place during the development of the mineralized tissues, The expression patterns of the transcripts encoding the bone matrix proteins suggest different biological roles depending on the time and site of expression.