Functional Genomics of Atrial Fibrillation in Human Atria

说明(申请人提供)：房颤(房颤)会增加心力衰竭、中风和死亡的风险，而且房颤被发现是一个重要的可遗传成分。全基因组关联研究发现了许多与房颤风险增加相关的单核苷酸多态(SNP)。然而，它们促进房颤的致病变异、相关基因和机制仍不清楚。为了加深我们对可遗传性房颤的致病基因的理解，我们建议评估最近在GWAS中发现的SNPs对感兴趣的靶组织-人左心房信使RNA、miRNA和相关蛋白表达的影响，该组织取自心脏手术患者的1000多个独特的人心房组织。具体目标是：1)确定房颤表型如何改变人类心房转录组，以及2)识别和测试改变心房转录表达的候选功能性遗传变异。目的1研究将使用最先进的技术(RNA-seq，miRNA-seq)和生物信息学来确定AF表型与基因转录本的相关性，包括低表达的转录本和mRNA异构体，miRNAs，以及共同调节的基因模块。我们将在心房肌细胞系、人胚胎干细胞来源的心房细胞和人的心房成纤维细胞中，测试使用siRNA敲除和基因转染策略调节选定基因的功能效果，以确定这些基因的表达变化是否影响下游基因的表达和选定的生物途径。目的2通过表达数量性状基因座(EQTL)和等位基因表达不平衡分析，寻找与心房肌基因表达相关的遗传变异。候选变异体将在报告基因转染研究中得到验证。建议的跨学科研究包括 这是一项对最近的GWA进行的合乎逻辑和重要的后续研究，它将为房颤高度相关的SNP对心房RNA表达模式的影响提供新的、公正的机械性见解。我们希望我们的研究能够确定房颤相关基因座和基因表达之间的功能联系，并确定与房颤的病因和进展相关的SNPs、基因和通路，这些可能成为房颤治疗和预防的新靶点。

DESCRIPTION (provided by applicant): Atrial fibrillation (AF) increases risk of heart failure, stroke and death, and AF has been found to have a significant heritable component. Genome wide association studies (GWAS) have identified numerous single nucleotide polymorphisms (SNPs) associated with increased risk of AF. However, the causative variants, relevant genes and mechanisms by which they promote AF remain unclear. To enhance our understanding of the causative genes involved in heritable AF, we propose to evaluate the impact of SNPs identified in recent GWAS on the expression of messenger RNA, miRNA and related proteins in the target tissue of interest, human left atria, taken from a unique biorepository of over 1000 human atrial tissues from cardiac surgery patients. Specific aims are: 1) To determine how AF phenotypes alter the human atrial transcriptome, and 2) To identify and test candidate functional genetic variants that alter atrial transcript expression. Aim 1 studies will use state-of-the-art technology (RNA-seq, miRNA-seq) and bioinformatics to determine AF phenotype associations with gene transcripts, including lowly expressed transcripts and mRNA isoforms, and miRNAs, and co-regulated gene modules. We will test the functional effects of regulating selected genes using siRNA knockdown and cDNA transfection strategies in an atrial myocyte cell line, human ESC-derived atrial cells and in human atrial fibroblasts to determine whether altered expression of these genes affects downstream gene expression and selected biological pathways. Aim 2 studies will identify genetic variants associated with atrial gene expression by expression quantitative trait locus (eQTL), and allelic expression imbalance analyses. Candidate variants will be validated in reporter gene transfection studies. The proposed interdisciplinary studies are a logical and important follow up to recent GWAS that will provide novel, unbiased mechanistic insights into the impact of SNPs highly associated with AF on atrial RNA expression patterns. We expect our studies to identify functional links between AF-associated genetic loci and gene expression, and to identify SNPs, genes, and pathways that are causally related to the etiology and progression of AF and that may represent new targets for AF treatment and prevention.