ATM-AMPK通过诱导自噬增强同源重组活性修复受精卵氧化应激性DNA双链断裂的机制研究

DNA损伤修复对于维持胚胎/子代基因组完整性及胚胎的正常发育至关重要。自噬在DNA修复和维持基因组稳定性方面起重要作用，但在体外培养的氧化应激导致DNA双链断裂（DSB）损伤受精卵中，自噬是否影响DSB修复还不清楚。我们前期在氧化应激性DSB损伤受精卵中检测到自噬水平增加，ATM和AMPK激活，分别抑制自噬水平、ATM和AMPK的激活，DSB损伤都明显加重，提示自噬、ATM和AMPK参与了DSB修复。鉴于同源重组（HR）途径能精准修复DSB损伤，我们假设，DNA损伤通过ATM-AMPK通路诱导激活自噬，进而通过增强HR活性促进DSB的修复，以维持氧化应激状态下受精卵基因组的稳定性。我们将通过建立DSB损伤受精卵模型来研究自噬对HR活性的影响和DSB的作用，及影响DSB修复的自噬形成的ATM-AMPK分子机制。本项目为了解受精卵DNA修复调控机制，及自噬对受精卵DNA修复的作用提供理论依据。

DNA damage repair is essential for maintaining the integrity of the embryo or offspring's genome and the normal development of the embryo. Autophagy plays an important role in repairing DNA damage and maintaining the stability of the genome, however, it is not clear whether autophagy affects the repair of DNA double-strand break (DSB) damage caused by oxidative stress in fertilized eggs cultured in vitro. We detected an increase in autophagy levels in oxidative stress-induced DSB-damaged fertilized eggs, and ATM and AMPK were activated. After inhibiting autophagy levels and activation of ATM and AMPK respectively, DSB damage was significantly aggravated, suggesting autophagy, ATM and AMPK involved in DSB repair. Homologous recombination (HR) pathway can accurately repair DSB damage. We hypothesize that DNA damage induces the activation of autophagy through the ATM-AMPK pathway, and then promotes the repair of DSB by enhancing HR activity to maintain the stability of the fertilized egg genome under oxidative stress. We will establish a DSB-damaged fertilized egg model to study the effect of autophagy on the HR activity and the role of DSB, as well as the molecular mechanism of ATM-AMPK inducing autophagy that affects DSB repair. This project provides a theoretical basis for understanding the regulatory mechanism of the DNA repair, and the effect of autophagy on DNA repair of fertilized eggs.