Developmental Regulation of Dentin Sialophosphoprotein during Ameloblast Differentiation: A Potential Enamel Matrix Nucleator
Developmental Regulation of Dentin Sialophosphoprotein during Ameloblast Differentiation: A Potential Enamel Matrix Nucleator
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DOI：
10.3109/03008209809023909
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发表时间：
1998-01-01
影响因子：
2.9
通讯作者：
D'Souza, R. N.
中科院分区：
文献类型：
--
作者：
MacDougall, M.;Nydegger, J.;D'Souza, R. N.
两种主要的牙本质基质蛋白，牙本质唾液蛋白和牙本质磷蛋白已被证明表达为单个大转录物，称为牙本质唾液磷蛋白（DSPP）。这些非胶原基质蛋白通过其独特的物理化学性质进行生化鉴定，是大亲本酸性磷酸化蛋白（pI 4.0）的特异性裂解产物。先前的研究表明成釉细胞在蛋白质水平上表达牙本质唾液酸蛋白。本研究的目的是确定釉质形成过程中 DSPP 表达的时空模式。对发育中的小鼠磨牙切片进行原位杂交和免疫组织化学分析。这些数据与富含成釉细胞的体外釉质器官上皮单层细胞培养物的 RT-PCR 分析相关。我们的数据表明 DSPP 转录物和蛋白质在分泌期之前的早期成釉细胞分化期间（此时大部分牙釉质基质形成）的初始表达。当釉质基质形成上调时，成釉细胞似乎会严格下调 DSPP 转录。这些数据表明，在釉质形成过程中 DSPP 的表达受到高度控制的发育调节。因此，DSPP 可能在牙釉质和牙本质的初始矿化过程中起主要作用，充当羟基磷灰石晶体形成的潜在成核剂。
The two major dentin matrix proteins, dentin sialoprotein and dentin phosphoprotein have been shown to be expressed as a single large transcript termed dentin sialophosphoprotein (DSPP). These non-collagenous matrix proteins, identified biochemically by their unique physical-chemical properties, are specific cleavage products of a large parent acidic phosphorylated protein (pI 4.0). Previous studies have shown expression of dentin sialoprotein at the protein level by ameloblasts. The purpose of this study was to determine the temporal-spatial pattern of DSPP expression during amelogenesis. In situ hybridization and immunohistochemistry were performed on sections of developing mouse molars. These data were correlated with RT-PCR analysis of in vitro enamel organ epithelium monolayer cell cultures enriched for ameloblasts. Our data indicates initial expression of the DSPP transcripts and protein during early ameloblast differentiation prior to the secretory phase when the majority of the enamel matrix is formed. Ameloblasts appear to tightly down-regulate DSPP transcription as enamel matrix formation is up-regulated. These data demonstrate DSPP expression during amelogenesis is under highly controlled developmental regulation. Therefore, DSPP may have a primary role in the initial mineralization events of both enamel and dentin, acting as a potential nucleator of hydroxyapatite crystal formation.