衰老相关蛋白NAP1L2在间充质干细胞介导牙周组织再生中的作用和表观遗传机制研究

体内衰老微环境和细胞倍增老化是制约间充质干细胞（MSC）介导牙周组织再生临床转化的关键问题。本组前期研究发现核小体组装蛋白NAP1L2在衰老骨髓间充质干细胞中高表达，并与组蛋白乙酰化修饰酶CBP/P300等有相互作用，调节H3K14乙酰化，抑制MSC成骨分化，提示以NAP1L2为靶点进行MSC修饰，可以促进其介导的牙周组织再生，但功能和机制尚不明确。课题拟揭示NAP1L2对MSC衰老、分化、免疫调节能力和牙周组织再生的作用。通过丧失性和获得性功能实验、蛋白印迹、ChIP-seq、Co-IP、ATAC-seq和蛋白质谱等方法研究NAP1L2和CBP/P300等对MSC衰老、分化和免疫调节关键分子转录调控的表观遗传机制，并建立动物模型，观察NAP1L2修饰对牙周组织再生的治疗作用。有望为理解间充质干细胞衰老等命运转归机制提供新思路，为牙周组织再生的临床转化提供新靶点和治疗策略。

The effects of aging micro-environment in vivo and replicative senescence on mesenchymal stem cells (MSC) are critical which restricting its clinical translation in periodontal tissue regeneration. Our previous studies found that the nucleosome assembly protein NAP1L2 highly expressed in senescent bone marrow mesenchymal stem cells and interacted with histone acetylation modifying enzymes, such as CBP/P300, to regulate H3K14 acetylation and thus inhibit MSC osteogenic differentiation. These data suggested that targeting NAP1L2 in MSC modification possess the promise in promoting periodontal tissue regeneration, but its function and mechanism remain unclear. Herein, the current proposal aims to reveal the effect of NAP1L2 on cell senescence, differentiation, immune regulation of MSC and periodontal tissue regeneration. By performing loss and acquired function experiments, Western Blotting, chromatin immunoprecipitation (ChIP), ChIP-seq, Co-IP, ATAC-seq, Protein Mass Spectrometry and bioinformatic analysis, we intend to investigate the key molecules, through which NAP1L2 and acetylation-related proteins regulate senescence, differentiation, and immunoregulation of MSC, and to elucidate the underlying transcriptional regulation epigenetic mechanisms of these key molecules. Moreover, by establishing animal models to study the therapeutic effects of NAP1L2 on periodontal tissue regeneration. It is expected to provide new ideas for understanding the mechanism of cell fate of MSC in cell senescence and aging micro-environment, therefore, provide new targets and treatment strategies for clinical translation in periodontal tissue regeneration.