Atg7-p53介导lncRNA APF促进自噬减轻心肌缺血损伤机制研究

研究显示，自噬上调可减轻心肌缺血损伤，长链非编码RNA APF上调自噬与Atg7相关。我们前期在心肌细胞缺氧模型中发现Atg7可与p53结合（Atg7-p53），其结合量与自噬水平均上调，但Atg7-p53是否参与缺血心肌自噬水平的调控尚不清楚。此外，我们在心肌缺氧/缺血模型中发现lncRNA APF表达显著上调；使用shRNA下调APF表达后，缺氧心肌损伤加重。因此，我们提出假设：APF可能通过上调Atg7-p53增强自噬，从而减轻心肌缺血损伤。本项目拟进行以下研究：①利用缺失突变、CO-IP等方法明确Atg7与p53结合区域；②构建结合区突变的Atg7载体病毒，结合形态学、分子生物学等方法阐明Atg7-p53对自噬的调控机制；③在Atg7结合区突变小鼠中过表达或敲低APF，揭示APF在Atg7-p53介导下可增强自噬水平最终减轻心肌缺血损伤。本项目有望为改善心肌缺血损伤提供新思路。

Previous studies have shown that the upregulation of autophagy during ischemia can reduce myocardial injury, and long non-coding RNA APF could upregulate autophagy by modulating Atg7. In our preliminary study, we have demonstrated that Atg7 binds to p53 in the neonatal rat cardiomyocytes（NRCs）hypoxia model, both the amount of Atg7-p53 and the level of autophagy are upregulated. But whether Atg7-p53 regulates autophagy during ischemia is unknown. To further explore its mechanism, we found in myocardial hypoxia/ischemia model lncRNA APF expression was significantly upregulated; the knock-down of APF by shRNA-APF interference increased hypoxic myocardial injury. we hypothesize that APF can up-regulate Atg7-p53, which further enhances autophagy and reduces myocardial ischemic damage. To verify this hypothesis, we intend to further in vitro and in vivo experiments: ① using deletion mutation of Atg7, CO-IP and other methods to illustrate the Atg7-p53 binding domain; ② constructing the Atg7-p53 binding domain mutation of ATG7 vector, combined with morphological and molecular biological methods to reveal the role of Atg7-p53 in the regulation of autophagy; ③ the overexpression or knock down of APF in Atg7-p53 binding zone mutant mice to reveal that APF/Atg7-p53 could increase autophagy level and reduce myocardial ischemia injury. This project is expected to reveal the specific mechanism of autophagy regulated by APF/Atg7-p53, and provide a new target for the treatment of myocardial ischemic disease.