自噬在非酒精性脂肪肝（NAFLD）发病中发挥着重要作用，但调控机制尚不明确。我们前期发现，肝脏中脂滴相关蛋白CGI58敲除后，会引起小鼠肝脏脂肪变性和非酒精性脂肪肝炎并伴随胰岛素抵抗，胰岛素受体底物I（IRSI）表达升高，mTOR表达升高，自噬标志物LC3减少。而IRSI是PI3K-Akt-mTOR上游调控因子，据此我们推测CGI58通过IRSI调控PI3K通路调节自噬。本项目拟在CGI58敲除动物和细胞基础上，构建Raptor/CGI58-LivKO双敲模型，检测抑制mTOR后肝脏脂肪变性指标，然后利用CGI58和IRSI高表达载体进行转染，检测在CGI58-KO中分别恢复CGI58和IRSI表达对mTOR、自噬和肝脏脂肪变性指标的影响，最后通过添加PI3K抑制剂，研究PI3K-Akt-mTOR是否在CGI58影响自噬过程中发挥关键作用，本研究结果将为阐明NAFLD发病机制提供新线索。

Autophagy plays an important role in the pathogenesis of nonalcoholic fatty liver disease (NAFLD), but the mechanism of regulation is still not clear.Our previous study found that when the lipid droplet-associated protein CGI58 is knocked out in the liver, it caused liver degeneration, non-alcoholic steatohepatitis and insulin resistance, and the expression of insulin receptor substrate I (IRSI) and mTOR increased, but the autophagy marker LC3 decreased.Based on the IRSI is a PI3K-Akt-mTOR upstream regulator, we speculate that CGI58 regulates autophagy through IRSI-regulated PI3K pathway.In this project, we first constructed a Raptor/CGI58-LivKO double-knock model on the basis of CGI58 knockout animals to detect liver steatosis after mTOR inhibition.Then, CGI58 and IRSI high expression vectors were used for transfection to detect the effects of CGI58 and IRSI up-expression on mTOR, autophagy, and hepatic steatosis in CGI58-KO model and cells.Finally, by adding PI3K inhibitors to study whether PI3K-Akt-mTOR plays a key role in CGI58-induced autophagy, the results of this study will provide new clues for elucidating the pathogenesis of NAFLD.