ABCA1 is direct target gene of miR-144-3p in chondrocyte

Abstract

Osteoarthritis (OA) is the most frequent disease of the musculoskeletal system, affecting millions of individuals around the globe. As a chronic disease, OA develops steadily over decades, eventually leading to joint degeneration. MicroRNAs are 20-25 nucleotide noncoding RNAs that modulate gene expression at the post-transcriptional level by binding to the 3'-UTR of target mRNAs, thereby inhibiting translation or inducing mRNA degradation. MicroRNA-144-3p was reported to be associated with osteoarthritis (OA) since it was upregulated in this disease. ABCA1 was also found to be involved in OA and a potential target of miR-144-3p by bioinformatics algorithms. This study aims to experimentally demonstrate that ABCA1 is the direct target of miR-144-3p. Initially, a mimic or inhibitor of miR-144-3p was transfected into the chondrocyte. Subsequently, the expression of ABCA1was determined by Real Time RT-PCR. The 3’UTR containing several binding sites of miR-144-3p and its mutated version were subcloned. A luciferase assay was performed to check the ability of miR-144-3p to bind to ABCA1. Real-time RT-PCR revealed that miR-144-3p overexpression inhibited ABCA1 expression. In contrast, when endogenous miR-144-3p decreased, ABCA1level increased. This result indicated that ABCA1 was the target of miR-144-3p. Particularly, luciferase assay results showed that miR-144-3p interacted directly with ABCA1 via its binding sites on the 3'UTR. These findings confirmed that miR-144-3p is the direct target of ABCA1.