Kong Xianguo, Simon Lukas M, Holinstat Michael, Shaw Chad A, Bray Paul F, Edelstein Leonard C
Leonard C. Edelstein, Department of Medicine Sidney Kimmel Medical College, Thomas Jefferson University, 1020 Locust Street, Suite 394, Philadelphia, PA 19107, USA, Tel.: +1 215 955 1797, Fax: +1 215 955 9170,
Thromb Haemost. 2017 May 3;117(5):962-970. doi: 10.1160/TH16-09-0692. Epub 2017 Mar 2.
Platelet activation in response to stimulation of the Protease Activated Receptor 4 (PAR4) receptor differs by race. One factor that contributes to this difference is the expression level of Phosphatidylcholine Transfer Protein (PCTP), a regulator of platelet PAR4 function. We have conducted an expression Quantitative Trait Locus (eQTL) analysis that identifies single nucleotide polymorphisms (SNPs) linked to the expression level of platelet genes. This analysis revealed 26 SNPs associated with the expression level of PCTP at genome-wide significance (p < 5×10). Using annotation from ENCODE and other public data we prioritised one of these SNPs, rs2912553, for functional testing. The allelic frequency of rs2912553 is racially-dimorphic, in concordance with the racially differential expression of PCTP. Reporter gene assays confirmed that the single nucleotide change caused by rs2912553 altered the transcriptional potency of the surrounding genomic locus. Electromobility shift assays, luciferase assays, and overexpression studies indicated a role for the megakaryocytic transcription factor GATA1. In summary, we have integrated multi-omic data to identify and functionalise an eQTL. This, along with the previously described relationship between PCTP and PAR4 function, allows us to characterise a genotype-phenotype relationship through the mechanism of gene expression.
蛋白酶激活受体4（PAR4）受体受到刺激后，血小板的激活存在种族差异。造成这种差异的一个因素是磷脂酰胆碱转移蛋白（PCTP）的表达水平，它是血小板PAR4功能的调节因子。我们进行了一项表达定量性状位点（eQTL）分析，以确定与血小板基因表达水平相关的单核苷酸多态性（SNP）。该分析揭示了26个在全基因组水平具有显著意义（p < 5×10）的与PCTP表达水平相关的SNP。利用ENCODE和其他公共数据的注释，我们将其中一个SNP，即rs2912553，优先用于功能测试。rs2912553的等位基因频率存在种族二态性，这与PCTP的种族差异表达一致。报告基因检测证实，rs2912553引起的单核苷酸变化改变了周围基因组位点的转录活性。电泳迁移率变动分析、荧光素酶检测和过表达研究表明巨核细胞转录因子GATA1发挥了作用。总之，我们整合了多组学数据来识别一个eQTL并对其进行功能验证。这一点，连同之前描述的PCTP与PAR4功能之间的关系，使我们能够通过基因表达机制来描述一种基因型-表型关系。
