Complex I 基因变异与寿命的关联及其作用机制的研究

The application hypothesis is that varies of mitochondrial Complex I (CI) encoded by nuclear (nDNA) and mitochondria (mtDNA) DNA would affect the human longevity. Our previous study have find-out the mtDNA coding CI gene (ND5) variant associated with human long-life, but nDNA encoding CI gene variants associated with life is still unknown. To test the hypothesis of mechanism of anti-aging for overall CI, we intend to use the pool exons sequencing, phylogenic tree, and bioinformatics analysis to identify the CI gene mutations associted with longevity, combining MitoCarta function prediction database; through testing and comparising CI gene mutations of nDNA and mtDNA among longevity, local natural age-group control and local middle-aged individuals with the metabolic syndrome populations, as well as their corresponding serum metabolism index levels, to access to CI physiological and biochemical evidences of genetic variants associated with longevity, determine CI variation impact on human life extension and its relationship with the body metabolism. From integrated CI level, we will explores these functional changes of CI-ND5 variation related to the key molecule targets in the process of ageing protection. Cellular mechanisms from cell biology experimental levels will give us a resonable explain on the mechanism occuring in human body, in order to describe the story of contribution to long-life elderly caused by CI mutations, the research is expected also to provide age-related diseases prevention and control of new ideas and relevant molecule targets.

本课题假设，编码线粒体Complex I(CI)的核(nDNA)和线粒体(mtDNA)基因变异对人类寿命延长均有影响。前期研究发现mtDNA编码CI基因变异影响人类寿命，然而nDNA编码的CI基因变异与寿命有关否仍未知。为从整体上检验CI变异延缓衰老的机制，拟应用pool外显子测序，系统发生和生物信息学分析识别长寿个体的CI 变异基因，并结合MitoCarta数据库进行功能预测；通过检测和比较长寿、当地自然衰老和当地中年代谢综合征个体的nDNA和mtDNA编码CI基因的变异，及其血清相应代谢指标水平，获得CI基因变异与长寿关联的生理和生化证据。在离体细胞层面考察CI(ND5)变异功能相关的关键靶点分子对衰老过程的保护作用。从细胞衰老及代谢退行性变的机制实验回到人体水平以阐述其作用机理，明确CI变异机制对延长寿命作用的贡献，及其与机体代谢水平的关系。有望为老年疾病防治提供新的思路和靶点。

与普通人群相比，经过健壮者存、病弱者亡，漫长岁月严格筛选的巴马长寿老人有可能携带有利于抗病和保持健康的基因。长寿老人的亲缘同胞及其后代患老年病的风险和频率，要显著低于普通老年人群。.本项NSFC资助课题的目的,是在前期全线粒体基因组扫描识别到线粒体ND5基因研究的基础上,探索核(非线粒体)基因组与巴马地区老年人群健康长寿的遗传关联,研究遗传变异与长寿个体对脂质代谢平衡的影响。因此，我们纳入了2816名长寿老人和2819名年龄组对照，开展了一项自然人群队列基础上的比较研究。通过全外显子测序和Sanger测序的基因型，我们鉴定了未见报道的新健康长寿遗传变异, 即HLA-DQB1（主要组织相容性复合体，II类，DQβ1），rs41542812 , rs1049107, rs1049100, rs3891176等位基因频率（Prange = 0.048-2.811×10-8），与中国巴马长寿人群队列中的长寿表型有关。此外，通过分析与血脂相关的长寿变异体，我们鉴定了HLA-DQB1 rs1049107，T携带者（PHDL = 0.006，OR：11.277; PTG = 9.095×10-7，OR：0.025; PLDL / HDL = 0.047，OR：1.901）和HLA-DQB1 rs1049100，与长寿命个体体内脂质平衡相关的T-携带者（PTG = 1.799×10-6，OR：0.028）。我们的生物信息学功能研究结果表明，长寿和脂质稳态与HLA-DQB1相关，指出了免疫基因变异体可能同时具有维持体内脂质平衡和延缓衰老的新功能(Aging, 2017)。.另外, 本项研究还识别到1个常见变异(MAP2K3 rs55935757 C/T)和8个罕见变异（TTN rs4893852，TTN rs13398235，TMEM156 rs2276887，PDHA2 rs35423663，EPB41L4B rs149000673，ZFN641 rs2732481，ATP5G2 rs17101603，RTN1 rs201516762）与中国广西人群长寿相关; 同时也验证了已有报道和本组既往识别到的APOE rs440446, PAX4 rs712700, FOXO3 rs9400239,CGNL1 rs1280396与中国广西人群长寿相关。