Ruch J V, Lesot H, Bègue-Kirn C
Institut de Biologie Médicale, INSERM U 424, Strasbourg, France.
Int J Dev Biol. 1995 Feb;39(1):51-68.
Odontoblasts are post-mitotic, neural crest-derived, cells which overtly differentiate according to tooth specific temporo-spatial patterns and secrete predentin-dentin components. Neither the timing nor the molecular mechanisms of their specification are known and the problem of their patterning in the developing jaws is far from being solved. On the other hand, some significative strides were made concerning the control of their terminal differentiation. Fibronectin interacting with a 165 kDa, non integrin, membrane protein intervenes in the cytoskeletal reorganization involved in odontoblast polarization and their terminal differentiation can be triggered in vitro by immobilized members of the TGF beta family. Histological aspects and the transcriptional phenotypes (transcripts of TGF beta s, BMPs, msxs, IGF1, fibronectin, osteonectin, bone sialoprotein genes) are very similar in vivo and in vitro. In vivo members of the TGF beta super family secreted by preameloblasts, trapped and activated by basement membrane associated components, might initiate odontoblast terminal differentiation.
成牙本质细胞是终末有丝分裂后、源自神经嵴的细胞，它们根据牙齿特定的时空模式进行明显分化，并分泌前期牙本质 - 牙本质成分。其分化的时间和分子机制均不明确，而且在发育中的颌骨中它们的模式形成问题远未得到解决。另一方面，在控制它们的终末分化方面取得了一些重要进展。与一种165 kDa的非整合素膜蛋白相互作用的纤连蛋白参与了成牙本质细胞极化过程中的细胞骨架重组，并且它们的终末分化在体外可由转化生长因子β（TGFβ）家族的固定成员触发。体内和体外的组织学特征以及转录表型（TGFβ、骨形态发生蛋白（BMP）、Msx、胰岛素样生长因子1（IGF1）、纤连蛋白、骨连接蛋白、骨唾液蛋白基因的转录本）非常相似。在体内，由成釉细胞分泌、被基底膜相关成分捕获并激活的TGFβ超家族成员可能启动成牙本质细胞的终末分化。
