ATF2转录激活METTL3通过m6A修饰NLRP3调控百草枯诱导肺泡巨噬细胞活化的分子机制

NLRP3介导百草枯诱导肺泡巨噬细胞活化机制不清。申请者发现百草枯诱导巨噬细胞中ATF2和METTL3表达增加，NLRP3 m6A修饰及表达增加；METTL3沉默后NLRP3 m6A修饰降低，NLRP3表达下降；IGF2BP2沉默后NLRP3表达降低；NLRP3 mRNA存在m6A修饰位点，METTL3启动子区存在ATF2结合位点。申请者推测ATF2转录激活METTL3通过m6A修饰增加NLRP3 mRNA稳定性及表达，从而调控百草枯诱导肺泡巨噬细胞活化。本项目拟在明确METTL3和IGF2BP2通过m6A调控NLRP3表达机制基础上，考察ATF2转录激活METTL3的作用，研究METTL3和IGF2BP2通过m6A修饰NLRP3调控百草枯诱导巨噬细胞活化的作用，阐明ATF2/METTL3/NLRP3轴调控百草枯诱导巨噬细胞活化的分子机制，为寻找可有效逆转百草枯中毒的新靶点提供实验依据。

The mechanisms that NLRP3 regulates the paraquat-induced macrophage activation is unclear. The increased ATF2, METTL3, and m6A methylation of NLRP3 were demonstrated in macrophages in rats administrated with paraquat based on our previous studies. The increased levels of NLRP3 m6A and NLRP3 expression were inhibited after METTL3 knockdown, and then the increased NLRP3 expression were inhibited after IGF2BP2 knockdown. There were some m6A modification sites in the NLRP3 mRNA and ATF2 binding sites were demonstrated to be in the promoter region of METTL3. Herein, we hypothesize that ATF2 may activate METTL3 transcriptionally via m6A-modified NLRP3 mRNA to regulate paraquat-induced alveolar macrophage activation. In this study, we will further investigate the effect of ATF2 on METTL3 transcription on the basis that METTL3 and IGF2BP2 regulate NLRP3 expression via m6A modification, and. Then, we will investigate the effects of METTL3/IGF2BP2 regulating the paraquat-induced macrophage activation via m6A-modified NLRP3 and illustrate the molecular mechanism that ATF2/METTL3/IGF2BP2 axis regulates paraquat-induced macrophage activation. Lastly, the experimental evidence of new targets of reversing paraquat poisoning effectively will be provided.