Molecular endophenotypes of H1 and H2 MAPT haplotypes

项目摘要 我们的长期目标是了解GWAs在负荷和 其他牛顿病症。我们目前提议的目标是开发小鼠模型，在该模型中， 全长190kb的人MAPT基因准确地取代了完整的157kb的小鼠MAPT基因，并 使用这些模型比较年轻和老年小鼠tau的分子内表型，表达 H2或H1 MAPT单倍型。我们的理论基础是定义H1和H2的非编码变体 单倍型在MAPT中存在，但在MAPT中不存在，这就需要完整的MAPT基因的整合。在……里面 此外，因为我们已经发现MAPT在小鼠基因组中的位置影响其 表达式中，我们将保留MAPT所在的Chr17q21.31的基本结构构型， 并保持其与老鼠和人类共享的基因簇中其他基因的关系。 这些研究将具有重要意义，因为它们将构成第一个非编码的体内生物检测 多态，为未来对GWASHITS的研究铺平了道路，不仅在负载上，而且在其他方面 慢性内科疾病。我们的主要假设是，进程和进程的差异 Tau mRNA和蛋白的表达模式是H2和H1相关风险变化的基础 MAPT单倍型。 我们已经拥有了第一个MAPT基因替换(GR)小鼠系，其中190kb的人H2 MAPT准确地取代了157KB的MAPT基因座，并将使用相同的方法来创建 H1 MAPT替换MAPT的精确匹配线。我们将测量和比较信使核糖核酸， 在年轻和老年GR1和GR2小鼠中tau的蛋白质和翻译后修饰。 在完成这些研究后，我们将创造和表征两个品系的小鼠 MAPT正好被MAPT的H1或H2变体所取代。我们预测，基因中不同的多态 H1和H2 MAPT将足以改变相对于GR2小鼠的GR1中tau的分子内表型， 而且这些差异会随着年龄的增长而增加。

Project Summary Our long-term goal is to understand the biological mechanisms underlying GWAS hits in LOAD and other tauopathies. The objective of our current proposal is to develop mouse models in which the entire 190 Kb human MAPT gene precisely replaces the complete 157 Kb mouse Mapt gene, and to use these models to compare the molecular endophenotypes of tau in young and old mice expressing H2 or H1 MAPT haplotypes. Our rationale is that the non-coding variants that define the H1 and H2 haplotypes are present in MAPT but not Mapt, necessitating the incorporation of the full MAPT gene. In addition, because we have found that the location of MAPT in the mouse genome affects its expression, we will preserve the basic structural configuration of Chr17q21.31 in which MAPT resides, and maintain its relationship relative to other genes in the gene cluster that mice and humans share. These studies will be significant because they will constitute the first in vivo bioassays of non-coding polymorphisms, paving the way for future research on GWAS hits in not only LOAD, but also other chronic medical disorders. Our overarching hypothesis is that differences in the progression and pattern of tau mRNA and protein expression underlie the variations in risk associated with H2 and H1 MAPT haplotypes. We have in-hand the first MAPT Gene-Replacement (GR) mouse line, in which the 190kb human H2 MAPT precisely replaces the 157 Kb Mapt locus, and will use the same methodology to create a precisely matched line in which the H1 MAPT replaces Mapt. We will measure and compare mRNA, protein and post-translational modifications of tau in young and old GR1 and GR2 mice. Upon completion of these studies, we will have created and characterized two lines of mice in which Mapt is precisely replaced by H1 or H2 variants of MAPT. We predict that the distinct polymorphisms in H1 and H2 MAPT will suffice to alter the molecular endophenotype of tau in GR1 relative to GR2 mice, and that these differences will increase with age.