Variation in platelet function: the genetics of platelet gene expression

血小板功能的变异：血小板基因表达的遗传学

基本信息

批准号：
7866180
负责人：
PAUL F. BRAY
金额：
$ 77.67万
依托单位：
THOMAS JEFFERSON UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-04-26 至 2014-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7866180
关键词：
3&apos Untranslated Regions Address Affect Age Agonist Alpha Granule Arterial Fatty Streak Bioinformatics Biological Markers Biology Blood Clot Blood Platelets Blood coagulation Cardiovascular Diseases Clinical Collagen Copy Number Polymorphism Coronary Occlusions DNA DNA Sequence Rearrangement Data Dose Epinephrine Ethnic Origin Exocytosis Exons F2R gene Figs - dietary Gender Gene Dosage Gene Duplication Gene Expression Genes Genetic Genetic Transcription Genomics Genotype Goals Human Individual Internet Introns Leukocytes Messenger RNA MicroRNAs Molecular Molecular Genetics Outcome P2X-receptor Pathway interactions Phenotype Physiological Physiology Platelet Activation Platelet aggregation Play Preparation Proteins RNA RNA Splicing Race Receptor Activation Relative (related person)Research Research Personnel Reverse Transcriptase Polymerase Chain Reaction Risk Ristocetin Role Rupture Sample Size Signal Transduction Stimulus Study Subject Testing Thrombosis Transcript Translations Variant Vascular Diseases Wound Healing base cDNA Expression cerebral artery cohort disorder risk drug development gene discovery genome wide association study insight mRNA Expression mortality novel overexpression public health relevance response secretory protein tool

项目摘要

DESCRIPTION (provided by applicant): There is extreme inter-individual variation in human platelet reactivity, which likely contributes to occlusion of coronary and cerebral arteries upon atherosclerotic plaque rupture in some individuals, whereas other individuals repair the wound without occluding the vessel. However, there is a lack of understanding of the molecular and genetic mechanisms responsible for this variation in platelet function. Our previous genome wide scan and platelet RNA expression studies have elucidated mechanisms for epinephrine-induced platelet aggregation, identified mRNA expression differences, as well as unexpected evidence that microRNAs (miRNAs) regulate expression of the platelet secretory protein, VAMP8. Additional analyses suggest that alternate exon splicing and genomic copy number variation also contribute to variation in platelet gene expression. Although our platelet RNA profiling study included 29 subjects, it was limited in its ability to identify genes involved in the platelet response to agonists other than epinephrine. We now propose to recall 180 subjects for new platelet phenotyping, preparation of leukocyte-depleted platelet RNA and microarray profiling of mRNA and miRNA. Rigorous bioinformatic and statistical approaches will minimize false positives, and candidate mRNAs and miRNAs will be characterized experimentally. This approach will allow definition of genes regulating the platelet response to specific agonists (ADP, CRP, collagen, TRAP, U46619, ristocetin, CD9 and epinephrine), as well as genes common to multiple platelet stimuli, and permit assessment of the effects of gender and ethnicity (Aim 1). In Aims 2-4 we will characterize molecular mechanisms regulating mRNA levels in platelets of differing reactivity. Our analyses will identify associations between platelet reactivity and alternately spliced exons, thus serving as a screen for functional domains in the platelet protein (Aim 2). We will determine platelet miRNA profiles and characterize the function of differentially expressed miRNAs in platelets of differing reactivity (Aim 3). By correlating RNA expression data with our prior GWAS genotyping on these same subjects, we will address the role of copy number variation on platelet gene expression (Aim 4). We will also generate public web tools that provide the relative expression of platelet mRNAs and miRNAs according to gender, race and age. This research will result in new insights into platelet physiology, enhance our understanding of the genetics of platelet gene expression, facilitate the selection of gender and race-specific biomarkers for thrombosis risk, and provide useful tools for other platelet researchers. PUBLIC HEALTH RELEVANCE: Cardiovascular disease is the major cause of mortality in the U.S. The goal of this research is to understand better the mechanisms that contribute to blood clotting in cardiovascular disease in order to develop better targets for drug development and better predictors of disease risk.

描述（由申请人提供）：人类血小板反应性存在极大的个体间差异，这可能导致某些个体在动脉粥样硬化斑块破裂时导致冠状动脉和脑动脉闭塞，而其他个体则在不闭塞血管的情况下修复伤口。然而，人们对血小板功能这种变异的分子和遗传机制缺乏了解。我们之前的全基因组扫描和血小板 RNA 表达研究已经阐明了肾上腺素诱导血小板聚集的机制，确定了 mRNA 表达差异，以及 microRNA (miRNA) 调节血小板分泌蛋白 VAMP8 表达的意想不到的证据。其他分析表明，交替外显子剪接和基因组拷贝数变异也导致血小板基因表达的变化。尽管我们的血小板 RNA 分析研究包括 29 名受试者，但其识别参与血小板对肾上腺素以外的激动剂反应的基因的能力有限。我们现在建议召回 180 名受试者进行新的血小板表型分析、去白细胞血小板 RNA 的制备以及 mRNA 和 miRNA 的微阵列分析。严格的生物信息学和统计方法将最大限度地减少假阳性，并且候选 mRNA 和 miRNA 将通过实验进行表征。这种方法将允许定义调节血小板对特定激动剂（ADP、CRP、胶原蛋白、TRAP、U46619、瑞斯托菌素、CD9 和肾上腺素）反应的基因，以及多种血小板刺激所共有的基因，并允许评估性别的影响和种族（目标 1）。在目标 2-4 中，我们将描述调节不同反应性血小板中 mRNA 水平的分子机制。我们的分析将确定血小板反应性和交替剪接外显子之间的关联，从而作为血小板蛋白功能域的筛选（目标 2）。我们将确定血小板 miRNA 谱并表征不同反应性血小板中差异表达 miRNA 的功能（目标 3）。通过将 RNA 表达数据与我们之前对这些相同受试者的 GWAS 基因分型相关联，我们将解决拷贝数变异对血小板基因表达的作用（目标 4）。我们还将生成公共网络工具，根据性别、种族和年龄提供血小板 mRNA 和 miRNA 的相对表达。这项研究将为血小板生理学带来新的见解，增强我们对血小板基因表达遗传学的理解，促进血栓形成风险的性别和种族特异性生物标志物的选择，并为其他血小板研究人员提供有用的工具。公共卫生相关性：心血管疾病是美国死亡的主要原因。这项研究的目标是更好地了解心血管疾病中导致血液凝固的机制，以便制定更好的药物开发目标和更好的疾病风险预测因子。