ClC-3参与氟斑牙发生的分子机制研究

Dental Fluorosis is caused by excess fluoride and shows defects in dental hard tissues. It is recently found that the variations of gene background may affect the risk of dental fluorosis among individuals. But it is not clear which gene is involved in this process. F type ClC channels could mediate fluoride transport in bacteria, and it is not demonstrated whether there are also some fluoride related ClC chloride channels in mammalian cells. According to our recent data of the human population survey and in vitro study, ClC-3 might play important roles in the fluoride transportation in mammals and is the key molecule of dental fluorosis. In this project, we will use zebrafish and yeast model as well as in vitro cell model to find out the genetic variants of ClC-3 coding genes among patients with dental fluorosis and analysis the risks of these variants in vitro and in vivo. We will explore the ClC-3 dependent fluoride transportation under physiological and pathological conditions and the deep mechanism by which ClC-3 is involved in the development of dental fluorosis. The research may help us to find the new mechanism by which fluoride is being transported in mammalian cells, and correctly understand the mechanisms and genetic background of dental fluorosis, which is essential for the preventing and interfering of dental fluorosis.

氟斑牙是由于环境中氟含量过高造成的一种牙体硬组织损害性疾病，近年研究表明，基因背景的差异可造成个体罹患氟斑牙程度的不同，但具体何种基因发挥关键作用尚不完全清楚。细菌研究表明ClC氯通道可特异性介导氟离子的外向转运，但哺乳动物是否存在氟离子相关的ClC氯通道还不清楚。我们前期人群调查和细胞体外实验结果提示，ClC-3氯通道可能在哺乳动物细胞的氟转运过程中发挥重要作用，是导致氟斑牙发生的关键分子。本课题拟通过斑马鱼模式动物系列实验、体外成釉细胞实验、酵母实验等，揭示生理和病理状态下ClC-3介导的氟离子跨膜转运机制，及其在氟斑牙发生中的作用；探讨ClC-3编码基因(CLCN3)的变异与氟斑牙发生的关系。这些研究有望揭示哺乳动物氟离子转运的新机制，正确理解氟斑牙的发生机制和遗传背景，对预防和有效干预氟斑牙的发生具有重要的意义。

氟斑牙是由于环境中氟含量过高造成的一种牙体硬组织损害性疾病，近年研究表明，基因背景的差异可造成个体罹患氟斑牙程度的不同，但具体何种基因发挥关键作用尚不完全清楚。我们通过人群调查发现，ClC-3氯通道的多态性与氟斑牙的发生有关；采用Morpholino技术建立clcn3基因敲降斑马鱼模型，采用CRISPR/Cas9技术构建clcn3基因敲除斑马鱼模型，通过系列斑马鱼模式动物模型，证实clcn3基因调控颅颌面骨以及牙发育和矿化，并且与自噬有一定关联；而且在高氟状态下，自噬路径与ClC-3的表达有关联。同时，我们发现ClC-3直接参与氟离子的跨膜转运，其转录形式会影响后续的高氟生物学效应。本项目通过体内和体外实验结果证实，ClC-3氯通道在哺乳动物细胞的氟转运过程中发挥重要作用，是导致氟斑牙发生的关键分子，揭示了哺乳动物氟离子转运的新机制，为正确理解氟斑牙的发生机制和遗传背景，对预防和有效干预氟斑牙的发生具有重要的意义。