The human rs1050286 polymorphism alters LOX-1 expression through modifying miR-24 binding

Area of Science:

• Molecular Biology
• Genetics
• Cardiovascular Research

Background:

• Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), encoded by OLR1, is upregulated in atherosclerosis pathogenesis.
• OLR1 gene polymorphisms are linked to increased susceptibility to acute myocardial infarction (AMI) and coronary artery diseases (CAD).
• Targeting LOX-1 overexpression is crucial for developing therapeutic strategies against these cardiovascular diseases.

Purpose of the Study:

• To investigate the regulatory role of hsa-miR-24 on OLR1 expression.
• To determine the impact of the rs1050286 single nucleotide polymorphism (SNP) on miR-24 binding and OLR1 regulation.
• To assess the potential of OLR1 SNP screening for stratifying patient risk for AMI and CAD.

Main Methods:

• Bioinformatic prediction of a hsa-miR-24 binding site in the OLR1 3'UTR, potentially altered by the rs1050286 SNP.
• Luciferase reporter assays to confirm miR-24 targeting of the OLR1 3'UTR variants (G vs. A allele).
• Overexpression of miR-24 in human cell lines (HeLa - A/G, HepG2 - A/A) to assess OLR1 RNA and protein level changes.

Main Results:

• Luciferase assays confirmed that miR-24 directly targets the G allele (3'UTR-G) of OLR1 but not the A allele (3'UTR-A).
• Overexpression of miR-24 led to significant downregulation of OLR1 RNA and protein levels in HeLa (A/G) cells, but not in HepG2 (A/A) cells.
• The rs1050286 SNP significantly affects miR-24 binding affinity, enhancing post-transcriptional gene repression in the presence of the G allele.

Conclusions:

• The rs1050286 SNP in OLR1 modulates the interaction with miR-24, influencing LOX-1 expression.
• This SNP-mediated regulation suggests a mechanism by which OLR1 variations may contribute to susceptibility to AMI and CAD.
• Screening for OLR1 SNPs could serve as a valuable tool for stratifying cardiovascular disease risk in patients.