Morini Elena, Rizzacasa Barbara, Pucci Sabina, Polidoro Chiara, Ferrè Fabrizio, Caporossi Daniela, Helmer Citterich Manuela, Novelli Giuseppe, Amati Francesca
Department of Movement, Human and Health Sciences, Foro Italico University, Rome, Italy.
Department of Biomedicine and Prevention, University of Rome Tor Vergata, Roma, Italy.
J Cell Mol Med. 2016 Jan;20(1):181-7. doi: 10.1111/jcmm.12716. Epub 2015 Nov 6.
The up-regulation of lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), encoded by the OLR1 gene, plays a fundamental role in the pathogenesis of atherosclerosis. Moreover, OLR1 polymorphisms were associated with increased susceptibility to acute myocardial infarction (AMI) and coronary artery diseases (CAD). In these pathologies, the identification of therapeutic approaches that can inhibit or reduce LOX-1 overexpression is crucial. Predictive analysis showed a putative hsa-miR-24 binding site in the 3'UTR of OLR1, 'naturally' mutated by the presence of the rs1050286 single nucleotide polymorphism (SNP). Luciferase assays revealed that miR-24 targets OLR1 3'UTR-G, but not 3'UTR-A (P < 0.0005). The functional relevance of miR-24 in regulating the expression of OLR1 was established by overexpressing miR-24 in human cell lines heterozygous (A/G, HeLa) and homozygous (A/A, HepG2) for rs1050286 SNP. Accordingly, HeLa (A/G), but not HepG2 (A/A), showed a significant down-regulation of OLR1 both at RNA and protein level. Our results indicate that rs1050286 SNP significantly affects miR-24 binding affinity to the 3'UTR of OLR1, causing a more efficient post-transcriptional gene repression in the presence of the G allele. On this basis, we considered that OLR1 rs1050286 SNP may contribute to modify OLR1 susceptibility to AMI and CAD, so ORL1 SNPs screening could help to stratify patients risk.
由OLR1基因编码的凝集素样氧化低密度脂蛋白受体1(LOX-1)的上调在动脉粥样硬化的发病机制中起重要作用。此外,OLR1基因多态性与急性心肌梗死(AMI)和冠状动脉疾病(CAD)易感性增加有关。在这些疾病中,确定能够抑制或减少LOX-1过表达的治疗方法至关重要。预测分析显示在OLR1的3'UTR中存在一个假定的hsa-miR-24结合位点,该位点因rs1050286单核苷酸多态性(SNP)的存在而“自然”突变。荧光素酶测定显示miR-24靶向OLR1 3'UTR-G,而非3'UTR-A(P < 0.0005)。通过在rs1050286 SNP杂合(A/G,HeLa)和纯合(A/A,HepG2)的人细胞系中过表达miR-24,确定了miR-24在调节OLR1表达中的功能相关性。因此,HeLa(A/G)而非HepG2(A/A)在RNA和蛋白质水平均显示出OLR1的显著下调。我们的结果表明,rs1050286 SNP显著影响miR-24与OLR1 3'UTR的结合亲和力,在存在G等位基因的情况下导致更有效的转录后基因抑制。在此基础上,我们认为OLR1 rs1050286 SNP可能有助于改变OLR1对AMI和CAD的易感性,因此ORL1 SNPs筛查有助于对患者风险进行分层。