去泛素化酶USP22调控HES1稳定性在成年神经再生与脑损伤修复中的机制研究

Traumatic brain injury (TBI) leads to a high morbidity and mortality, while neurological repair is crucial to the outcome. The regulation of proliferation and differentiation of adult neural stem cells (NSCs) is the hotspot of recent research on brain injury repair, in which HES1 plays an important role confirmed in our previous works. The stability of HES1 protein is regulated by the ubiquitin-proteasome pathway, but the specific mechanism has not been elucidated. Our previous studies confirmed that the ubiquitination level of HES1 was increased after TBI, while the expression of USP22 and HES1 were decreased, and USP22 regulates HES1 protein stability. Accordingly, we hypothesize that USP22 regulates HES1 stability affecting adult neurogenesis and brain injury repair. Based on our previous work, using in vivo and in vitro ubiquitination experiments, morris water maze and other methods, we intend to investigate USP22 regulates HES1 protein level through the de-ubiquitination; The effect of USP22 on the proliferation and differentiation of NSCs in vivo and in vitro by regulating HES1 protein. Next, we study the role of USP22 on the adult neurogenesis and brain injury repair in TBI mouse model by overexpressing or knockdown USP22. This study will be an important complement to the regulation mechanism of adult neurogenesis by USP22, which will provide a new target for neurological repair of brain injury and provide a theoretical basis for clinical treatment of TBI.

创伤性脑损伤（TBI）致死致残率高，神经功能修复是其预后关键。成年神经干细胞（NSCs）增殖分化调控是近期脑损伤修复研究热点，前期证实HES1蛋白在其中起重要作用。HES1稳定性受泛素-蛋白酶体途径调节，但其机制尚未阐明。课题组前期发现TBI后，HES1泛素化水平升高，而去泛素化酶USP22和HES1蛋白水平降低，且USP22影响HES1蛋白稳定性。据此，我们提出科学假说，USP22调控HES1稳定性影响成年神经再生与脑损伤修复。课题组拟用体内外泛素化实验、Morris水迷宫等方法探究USP22对HES1蛋白的去泛素化修饰调节；研究USP22通过调控HES1对成年体内、外NSCs增殖分化的影响；在小鼠TBI模型中研究敲减或过表达USP22对成年神经再生及脑损伤修复的影响。此研究是USP22参与调控成年神经再生机制的重要补充，为TBI神经功能修复提供新的靶点，为TBI临床治疗提供理论基础。

创伤性脑损伤（TBI）具有极高的致死率和致残率，神经功能修复在轻中度TBI患者的预后过程中起关键性作用。我们课题组发现HES1蛋白在神经干细胞（NSCs）增殖分化调控中发挥了重要的作用，明确了HES1稳定性受泛素-蛋白酶体途径调节。课题组通过体内外泛素化实验、Morris水迷宫等方法探究USP22对HES1蛋白的去泛素化修饰调节；研究USP22通过调控HES1对成年体内、外NSCs增殖分化的影响；在小鼠TBI模型中研究敲减或过表达USP22对成年神经再生及脑损伤修复的影响。明确了HES1和USP22具有相互作用并在体外NSCs的增殖和分化过程中发挥了重要的作用。明确了调控海马DG区USP22的表达可以影响小鼠TBI模型的认知功能。此研究是USP22参与调控成年神经再生机制的重要补充，为TBI神经功能修复提供新的靶点，为TBI临床治疗提供理论基础。