Abstract: Objective To explore the dynamic expression level of calcium-phospholipid-binding protein Ⅶ (Cpne7) in different stages of mouse tooth development model, and determine its dynamic expression level and distribution during dentigenesis. Method The expression of Cpne7 in the development of the first mandibular molar of C57Bl / 6 mice was studied by immunohistochemistry, in situ hybridization, real-time PCR and Western blot. At the same time, HAT-7 and hDPCs were cultured and analyzed by real-time PCR and Western blot to determine the level of Cpne7 mRNA and protein expression during cell differentiation. Result Cpne7 participates in the early differentiation of ameloblasts and odontoblasts. During initiation ( bud stage) , Cpne7 protein was expressed in dental epithelial cells, but not in dental mesenchyme. At E18 ( bell stage) , Cpne7 protein and mRNA were mainly expressed in the ectodermal mesenchymal cells of the dental papilla. At P7 ( crown formation stage ) , Cpne7 was expressed in differentiated odontoblasts, but weak expression was detected in mature ameloblasts. During dentin generation, Cpne7 was obviously expressed in differentiated dentin cells and odontoblast, but not in fully differentiated dentin cells. In addition, Cpne7 was expressed in the HERS and in the odontoblasts at the time of root dentin formation. Conclusion Cpne7 is not only involved in odontogenic differentiation, but also in the process of odontogenesis and dentin formation of root dentin and crown dentin. Cpne7 shows dynamic spatiotemporal expression during tooth development, and plays an important role in the whole tooth development stage.

Key words: calcium phospholipid-binding protein Ⅶ, murine model, tooth development, dynamic expression, dentin, distribution

摘要： 目的 探讨钙磷脂结合蛋白 Ⅶ ( Cpne7) 在小鼠牙齿发育模型中不同阶段的动态表达水平及分布情况。方法 选取 C57Bl / 6 小鼠牙齿不同发育阶段样本,采用免疫组织化学、原位杂交、实时 PCR 和 Western blot 等方法研究小鼠下颌第一磨牙牙体发育过程中 Cpne7 的表达规律。 同时培养 HAT-7 和人牙髓细胞( hDPCs) 并进行实时PCR 和蛋白质印迹分析,明确细胞分化过程中 Cpne7 mRNA 和蛋白表达的水平。 结果 Cpne7 参与成釉细胞和成牙本质细胞的早期分化。 在起始期( 蕾状期) ,Cpne7 蛋白在牙上皮细胞中表达,但在牙间质中未见表达。 在E18(钟状期) ,Cpne7 蛋白和 mRNA 主要在牙乳头的外胚间充质细胞中表达。 在 P7(牙冠形成期) ,Cpne7 在分化的成牙细胞中表达,在成熟的成釉细胞中检测到微弱的表达。 在牙本质发生过程中,Cpne7 在成牙本质细胞分化和成牙本质过程中表达明显,但在完全分化的成牙本质细胞中不再表达。 此外,Cpne7 在 Hertwig 的上皮根鞘( HERS) 和根牙本质形成时的成牙本质细胞中表达。 结论 Cpne7 不仅参与成牙本质分化,还参与根牙本质和冠牙本质的成牙本质过程和牙本质形成,Cpne7 在牙齿发育过程中呈动态时空表达,在整个牙齿发育阶段起重要作用。

关键词: 钙磷脂结合蛋白Ⅶ, 小鼠模型, 牙齿发育, 动态表达, 牙本质, 分布情况