From the Shantou University Medical College, China (G.Z., W.Y., J.W., B.C., X.Y., S.Y.).
Department of Histology and Embryology, Guilin Medical University, China (G.Z.).
Arterioscler Thromb Vasc Biol. 2018 Aug;38(8):1837-1844. doi: 10.1161/ATVBAHA.118.311030.
Objective- Genome-wide association studies have revealed a robust association between genetic variation on chromosome 15q26.1 and coronary artery disease (CAD) susceptibility; however, the underlying biological mechanism is still unknown. The lead CAD-associated genetic variant (rs17514846) at this locus resides in the FURIN gene. In advanced atherosclerotic plaques, furin is expressed primarily in macrophages. We investigated whether this CAD-associated variant alters FURIN expression and whether furin affects monocyte/macrophage behavior. Approach and Results- A quantitative reverse transcription polymerase chain reaction analysis showed that leukocytes from individuals carrying the CAD risk allele (A) of rs17514846 had increased FURIN expression. A chromatin immunoprecipitation assay revealed higher RNA polymerase II occupancy in the FURIN gene in mononuclear cells of individuals carrying this allele. A reporter gene assay in transiently transfected monocytes/macrophages indicated that the CAD risk allele had higher transcriptional activity than the nonrisk allele (C). An analysis of isogenic monocyte cell lines created by CRISPR (clustered regularly interspaced short palindromic repeats)-mediated genome editing showed that isogenic cells with the A/A genotype for rs17514846 had higher FURIN expression levels than the isogenic cells with the C/C genotype. An electrophoretic mobility shift assay exhibited preferential binding of a nuclear protein to the risk allele. Studies of monocytes/macrophages with lentivirus-mediated furin overexpression or shRNA (short hairpin RNA)-induced furin knockdown showed that furin overexpression promoted monocyte/macrophage migration, increased proliferation, and reduced apoptosis whereas furin knockdown had the opposite effects. Conclusions- Our study shows that the CAD-associated genetic variant increases FURIN expression and that furin promotes monocyte/macrophage migration and proliferation while inhibiting apoptosis, providing a biological mechanism for the association between variation at the chromosome 15q26.1 locus and CAD risk.
目的-全基因组关联研究显示,染色体 15q26.1 上的遗传变异与冠心病(CAD)易感性之间存在稳健的关联;然而,其潜在的生物学机制尚不清楚。该基因座上与 CAD 相关的主要遗传变异(rs17514846)位于 FURIN 基因内。在晚期动脉粥样硬化斑块中,furin 主要在巨噬细胞中表达。我们研究了这种与 CAD 相关的变异是否改变 FURIN 的表达,以及 furin 是否影响单核细胞/巨噬细胞的行为。方法和结果-实时定量聚合酶链反应分析显示,携带 rs17514846 风险等位基因(A)的个体白细胞中 FURIN 表达增加。染色质免疫沉淀分析显示,携带该等位基因的单核细胞中 RNA 聚合酶 II 占据 FURIN 基因的位置更高。瞬时转染的单核细胞/巨噬细胞的报告基因检测表明,CAD 风险等位基因的转录活性高于非风险等位基因(C)。通过 CRISPR(成簇规律间隔短回文重复)介导的基因组编辑创建的同基因单核细胞系分析表明,rs17514846 的 A/A 基因型同基因细胞的 FURIN 表达水平高于 C/C 基因型同基因细胞。电泳迁移率变动分析显示,核蛋白优先与风险等位基因结合。用慢病毒介导的 furin 过表达或 shRNA(短发夹 RNA)诱导的 furin 敲低研究单核细胞/巨噬细胞的结果表明,furin 过表达促进单核细胞/巨噬细胞迁移,增加增殖,减少凋亡,而 furin 敲低则产生相反的效果。结论-我们的研究表明,与 CAD 相关的遗传变异增加了 FURIN 的表达,furin 促进单核细胞/巨噬细胞迁移和增殖,同时抑制凋亡,为染色体 15q26.1 位点的变异与 CAD 风险之间的关联提供了生物学机制。