阿尔茨海默病PLD3基因深度测序及其罕见突变的致病机制研究

项目名称： 阿尔茨海默病PLD3基因深度测序及其罕见突变的致病机制研究

项目编号： No.81501103

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 医药、卫生

项目作者： 谭梦姗

作者单位： 青岛大学

项目金额： 21万元

中文摘要： 高加索人群二代测序发现PLD3为LOAD新的致病基因，其罕见突变增加患病风险2倍。由于各种族人群遗传背景存在差异，目前PLD3是否与汉族人群LOAD风险相关，及其突变导致AD的分子机制尚未明确。我们前期已建立汉族人群LOAD资源库，并率先在PLD3第11号外显子检测到全新错义突变R356H和剪接位点突变c.1020-8G>A。本项目在此基础上，拟对PLD3除11号外显子外其他关键区域进行二代高通量测序，精确定位所有变异位点频率分布，筛选出与汉族人群LOAD风险相关的变异位点。此外，拟构建携带c.1020-8G>A突变Minigene质粒，及携带R356H突变真核表达载体，瞬时转染细胞后，研究上述突变对其mRNA前体剪接以及编码蛋白转录表达的影响。进一步构建慢病毒介导的稳转细胞模型，研究PLD3突变对Aβ病理、神经元及突触的影响，阐明PLD3突变导致AD的分子机制，并为AD诊疗提供全新靶点。

中文关键词： 阿尔茨海默病；PLD3；二代高通量测序；β-淀粉样蛋白；发病机制

英文摘要： Recently, a whole-exome sequencing (WES) study has shown that a rare variant of the phospholipase D3 (PLD3) gene confers a doubled risk for late-onset Alzheimer’s disease (LOAD) in Caucasian population. Due to the differences in genetic background, whether PLD3 is still associated with LOAD risk in Han Chinese remains largely unclear; and few studies focus on the detailed mechanisms of the rare mutations of PLD3 in AD pathogenesis. In our preliminary studies, we have provided the first evidence that a novel missense mutation (R356H) and a splicing mutation (c.1020-8G>A) in exon 11 of PLD3 were associated with LOAD risk in Han Chinese. Our current researches intend to further map PLD3 to fully identify risk variants for LOAD in a large Han Chinese cohort. In addition, the Minigene plasmids for c.1020-8G>A mutation was constructed and transfected into cells, and the effect of c.1020-8G>A mutation on pre-mRNA splicing was analyzed. R356H mutation was introduced into pcDNA3.1/PLD3 vector, and expression characteristics of PLD3 in transfected cells were measured. Meanwhile, the regulatory roles of PLD3 mutations in Aβ, neuronal and synaptic pathology were confirmed in lentivirus stably transfected cell lines. This project will provide theoretic support for early genetic diagnosis of AD in Han Chinese, and offer more information for molecular therapy via uncovering its underlying pathogenesis.

英文关键词： Alzheimer's disease;PLD3;Next-generation sequencing;β-amyloid;Pathogenesis