Abstract:
Genome-wide association studies have revealed an association between the genetic variant rs17514846 in the FURIN gene and coronary artery disease. We investigated the mechanism through which rs17514846 modulates FURIN expression. An analysis of isogenic monocytic cell lines showed that the cells of the rs17514846 A/A genotype expressed higher levels of FURIN than cells of the C/C genotype. Pyrosequencing showed that the cytosine (in a CpG motif) at the rs17514846 position on the C allele was methylated. Treatment with the DNA methylation inhibitor 5-aza-2\'-deoxycytidine increased FURIN expression. An electrophoretic mobility super-shift assay with a probe corresponding to the DNA sequence at and around the rs17514846 position of the C allele detected DNA-protein complex bands that were altered by an anti-MeCP2 antibody. A chromatin immunoprecipitation assay with the anti-MeCP2 antibody showed an enrichment of the DNA sequence containing the rs17514846 site. siRNA-mediated knockdown of MeCP2 caused an increase in FURIN expression. Furthermore, MeCP2 knockdown increased monocyte migration and proliferation, and this effect was diminished by a FURIN inhibitor. The results of our study suggest that DNA methylation inhibits FURIN expression and that the coronary artery disease-predisposing variant rs17514846 modulates FURIN expression and monocyte migration via an allele-specific effect on DNA methylation.
摘要:
全基因组关联研究揭示了FURIN基因中的遗传变异rs17514846与冠状动脉疾病之间的关联。我们研究了rs17514846调节FURIN表达的机制。对等基因单核细胞系的分析表明,rs17514846A/A基因型的细胞比C/C基因型的细胞表达更高水平的FURIN。焦磷酸测序显示C等位基因上rs17514846位置的胞嘧啶(在CpG基序中)被甲基化。用DNA甲基化抑制剂5-氮杂-2'-脱氧胞苷处理可增加FURIN表达。使用与C等位基因的rs17514846位置及其周围的DNA序列相对应的探针进行的电泳迁移率超移位测定检测到的DNA-蛋白质复合物条带被抗MeCP2抗体改变。使用抗MeCP2抗体的染色质免疫沉淀测定显示含有rs17514846位点的DNA序列的富集。siRNA介导的MeCP2敲低导致FURIN表达增加。此外,MeCP2敲除增加单核细胞的迁移和增殖,FURIN抑制剂减弱了这种作用。我们的研究结果表明,DNA甲基化抑制FURIN表达,冠状动脉疾病易感变异体rs17514846通过对DNA甲基化的等位基因特异性作用调节FURIN表达和单核细胞迁移。