三氯生靶向FTO介导的m6A甲基化修饰异常致斑马鱼脂肪代谢紊乱的调控新机制

三氯生（TCS）被广泛用于化工和医药等行业，其环境污染引发的慢性致毒效应对水生物和人类健康构成威胁。在前基金后续研究中发现：TCS暴露诱导脂肪代谢紊乱，FTO表达上升，而METTL3无变化，但已有关于脂肪代谢的调控机制存在争议和相悖之处。为此，本项目以TCS暴露下异常变化且与肥胖相关的RNAm6A去甲基化酶FTO为切入点，探讨TCS靶向FTO介导m6A修饰对脂肪代谢紊乱的调控作用，及其在相关miRNA加工成熟中的修饰新机制。从崭新的miRNAm6A修饰角度揭示TCS间接靶向FTO的下游调控机制。上游反向寻找调控FTO变化的转录因子，步步反推，率先用斑马鱼活体探索对接于新型雌激素膜受体GPER或跨膜Wnt通路的作用途径，挖掘FTO变化源头，阐明TCS直接作用的新靶标新机制。整合上下游关系，构建以FTO为枢纽的调控网络，增进对污染性脂肪代谢紊乱疾病的认识与控制，为污染生态的预警和修复提供参考。

Triclosan (TCS) is a kind of broad-spectrum bactericide, which is widely used in medical and chemical industries. Due to frequent use, it poses a great concern to aquatic organisms and human health. In the follow-up study of our previous NSFC (31770552), we found that when zebrafish (Danio rerio) were exposed to TCS, fat metabolism disorder was induced, and FTO expression increased, but no expression changes in METTL3 was observed. So far, there were many different reports and contradictory ideas on the regulation mechanism of fat metabolism. Herein, FTO, an obesity-related gene and a demethylated enzyme of RNAm6A, and its abnormal expression due to TCS-exposure will be utilized as breakthrough point in this proposal. TCS-induced molecular mechanisms will be disclosed by means of the following researches: the regulatory role of FTO-mediated m6A modification in fat metabolism disorder, and the modification mechanisms on the related miRNAs in its processing maturity. That is to say that the above researches aim to illustrate the downstream regulation mechanism on indirect TCS-targeted FTO from the viewpoint of novel miRNAm6A modification. In upstream, the transcription factors that regulated FTO changes were reversely searched step by step, and explored the action pathway docking on the novel estrogen membrane receptor GPER or transmembrane Wnt pathway using zebrafish as model organism. The aforementioned analyses aim to demonstrate the changing source of FTO, and further elucidate the new target and mechanisms of TCS-induced effects. By integrating the upstream with downstream regulatory relationship, a regulatory network will be constructed with FTO as the hub. This study can improve our understanding and intervention on fat metabolism disorder resulting from environmental pollution, and provide reference for early warning and restoration of polluted ecology.