吸烟可导致神经元损伤，但其分子机制不清。m6A甲基化引起的miRNA的加工成熟参与多种疾病的发生发展，但其在吸烟致神经元损伤中的作用和机制尚无报道。申请者最近发现，m6A甲基转移酶可促进pri-miR-200加工为miR-200b/c，后者参与香烟烟雾抽提物（CSE）所致胰岛素抵抗、Tau蛋白过度磷酸化和突触损伤。据此，本项目拟采用m6A pri-miRNA甲基化测序、RNA共沉淀联合质谱鉴定、小鼠脑内立体定位注射等技术，分析m6A甲基化引起miR-200b/c水平升高与CSE所致胰岛素抵抗和神经细胞损伤之间的关联；揭示CSE致miR-200b/c上调对PI3K的抑制作用及其结合位点；确定m6A甲基转移酶METTL3在miR-200b/c加工过程中的关键作用；在动物整体水平验证METTL3和miR-200b/c在香烟致神经元损伤中的作用和分子机制。研究结果对控烟和预防吸烟危害具有指导意义。

Smoking can cause neuronal damage, but its molecular mechanism is unclear. M6A methylation mediates miRNA processing maturation, participates in the occurrence and development of various diseases, but its role and mechanism in smoking-induced neuronal damage have not been reported. The applicant recently discovered that m6A methyltransferase can promote the processing of pri-miR-200 into miR-200b/c, which is involved in cigarette smoke extract (CSE) induced insulin resistance, Tau protein hyperphosphorylation and synaptic damage. Based on this, the project intends to use m6A pri-miRNA methylation sequencing, RNA Immunoprecipitation combined with mass spectrometry identification, stereotaxic injection in the brain of mice and other technologies.Analysis of the association between increased miR-200b/c levels caused by m6A methylation and CSE-induced insulin resistance and nerve cell damage.Reveal the inhibitory effect of CSE-induced miR-200b/c on PI3K and its binding site.Determine the key role of METTL3 in the processing of miR-200b/c.In addition, the role and molecular mechanism of METTL3 and miR-200b/c in cigarette-induced neuronal damage were verified in the mouse model. The results of the study are of guiding significance for cigarette control and prevention of smoking hazards.