CRE MOUSE MODELS TO STUDY AMELOGENESIS

项目摘要/摘要 2017年6月，一组牙科研究人员在NIDCR会面，讨论牙釉质研究的未来和 在总结发言中得出结论，在牙釉质研究领域，缺乏研究牙釉质的模型 形成和疾病阻碍了最近的进展。研究小组得出结论，更合适的成釉细胞- 与细胞系一样，对有机体和芯片技术以及新的动物模型的投资可以用来促进 田野。关于动物模型，我相信釉质研究人员因为没有釉质器官而苦恼- 特异性Cre重组酶突变小鼠。在过去的20年里，牙釉质研究人员一直使用Krt14-CRE (角蛋白14-Cre重组酶)突变体与不同loxP杂交研究釉质特异性活性 老鼠线。使用Krt14-Cre小鼠进行釉质研究的显著缺点是Krt14 在多种组织中表达，包括皮肤、支气管上皮、舌头、气管、唾液腺和许多 更多的器官，正因为如此，许多已开发的loxp小鼠系不适合研究 成釉作用。例如，阴离子交换蛋白(Slc4a2/Ae2)的mRNA表达水平，或 囊性纤维化跨膜电导调节剂(CFTR)，分别增加~6倍和3倍 成熟期的釉质器官(与分泌期相比)和牙齿形成后的两个基因 在肺和胰腺中广泛表达，对它们的发育至关重要。Slc4a2-空和cftr-空 老鼠有严重的釉质病变。用Krt14-Cre突变小鼠研究AE2fl/fl或 Cftrfl/fl会有很大的局限性，因为这些动物可以预见会遭受多个器官的损害。 年轻时就失败了。我建议建立两种动物模型，将Cre重组酶敲击到 成釉细胞蛋白(AMBN)和成牙本质成釉细胞相关基因(ODAM)基因座Cre的表达 仅限于分泌型成釉细胞和成熟型成釉细胞。这笔赠款的UG3阶段将是 致力于开发这两种动物模型：AMBN-CRE和ODAM-CRE，UH3阶段将 验证这两种动物作为研究釉质发生的独特体内模型。在这个项目完成时 来自这些动物的数据将被公布，两条线都存放在适当的设施中，如 Mutamt老鼠资源和研究中心(MMRRC)。

PROJECT SUMMARY / ABSTRACT In June of 2017 a group of dental researchers met at the NIDCR to discuss the future of enamel research and concluded, in a summary statement, that in the field of enamel research, a lack of models to study enamel formation and disease has hampered recent progress. The group concluded that more appropriate ameloblast- like cell lines, investment in organoid and chip technology and novel animal models could be used to advance the field. With respect to animal models, I believe enamel researchers suffer from not having enamel organ- specific Cre recombinase mutant mouse. For the past 2 decades enamel researchers have used the Krt14-Cre (keratin 14-Cre recombinase) mutant to study enamel-specific activities by cross breeding with various loxP mouse lines. The significant disadvantage of using the Krt14-Cre mouse for enamel research is that Krt14 is expressed in multiple tissues including skin, bronchial epithelia, tongue, trachea, salivary glands, and many more organs, and because of this many of the developed loxP mouse lines are not appropriate to study amelogenesis. For example, mRNA expression levels of the anion exchanger protein (Slc4a2/AE2), or the cystic fibrosis transmembrane conductance regulator (Cftr), increases ~ 6-fold and 3-fold respectively in the enamel organ during maturation stage (compared to secretory stage), and beyond tooth formation both genes are widely expressed in lung and pancreas and are critical to their development. Both Slc4a2-null and Cftr-null mice have severe enamel pathologies. To use the Krt14-Cre mutant mouse to study the role of either AE2fl/fl or Cftrfl/fl would have significant limitations because these animals would predictably suffer from multiple organ failures at a young age. I propose to develop two animal models with a knockin of Cre recombinase into the ameloblastin (Ambn) and odontogenic ameloblast-associated (Odam) gene loci such that Cre expression is limited to secretory ameloblasts and maturation ameloblasts respectively. The UG3 stage of this grant will be devoted to the development of these two animal models; Ambn-Cre and Odam-Cre, and the UH3 phase will validate these two animals as unique in vivo models to study amelogenesis. At the completion of this project data from these animals will be published, and both lines deposited in an appropriate facility such as the Mutamt Mouse Resource and Research Centers (MMRRC).