p53调控脑缺血再灌注损伤的机制始终未明确。我们前期工作已在体外证实p53可通过mTOR通路调控神经元OGD损伤，且与脑缺血损伤时的重要调控因子PRAS40蛋白关系密切。因而我们提出p53可能通过对PRAS40的直接转录调控影响mTOR通路活性，从而参与脑缺血损伤的假说。为此本课题首先应用p53相关慢病毒载体及p53基因神经元特异敲除小鼠在体内外确认p53对脑缺血损伤的调控作用，并证实该作用通过mTOR通路而产生；进一步应用PRAS40基因敲除小鼠，结合系列实验证实PRAS40是p53的直接转录调控靶点，介导p53-mTOR对脑缺血损伤的调控作用。最后观察p53-PRAS40-mTOR对缺血后神经元自噬的影响。本课题应用转基因动物、细胞、慢病毒载体等多种手段证实三者的关联，期望阐明p53-PRAS40-mTOR这一新信号通路在脑缺血调控中的机制，为脑缺血的临床治疗提供新的依据和思路。

p53 is an important molecule related with cerebral ischemia-reperfusion injury, and its mechanism remains unclear. Our previous works show that p53 regulates the OGD-induced injury in primary neuronal cultures, which is related with PRAS40 and mTOR pathway. Thus we hypothesized that p53, as a key factor in regulating stress, may affect the mTOR pathway by directly regulating the transcription of PRAS40 gene, then participate the process of cerebral ischemia-reperfusion injury. Autophagy may be another important mechanism. To confirm the hypothesis, we will use p53-associated lentivirus and p53 neuron-specific knockout mice (p53-N-KO) to study the role of p53 against ischemia in vivo and in vitro, and to determine if such effects come through mTOR pathway; Then we used PRAS40 KO mice to further observe if PRAS40 deletion will cause the absence of p53 regulation against cerebral ischemia, and in vitro transfection are also used to confirm PRAS40 is one of the direct transcriptional targets of p53; finally we detect the function of p53-PRAS40-mTOR pathway on regulating the neuronal autophagy. In this project, we use transgenic animals, cells and lentivirus vectors to find out the important effects and mechanism of novel p53-PRAS40-mTOR signaling pathway against in cerebral ischemia - reperfusion injury, which will provide the new basis and ideas for clinical treatment of cerebral ischemia.