Genome-wide analysis of genes regulated by miR-126-3p in primary human lung microvascular endothelial cells (HLMVEC)

The goal of this study is to investigate the cell type-specific targets of miR-126-3p in human lung microvascular endothelial cells (HLMVEC). Following the transfections of HLMVEC with non-targeting negative controls, miR-126 mimics, or miR-126 antisense inhibitors, we calculated the copy number concentration of miR-126 in each sample and performed genome-wide RNA sequencing. Plotting the gene expression data for each transfection condition (Scramble, 126-OE and 126-KD) against their respective miR-126 concentrations, we performed a linear regression analysis to discover genes that were the most sensitive to changes in miR-126 levels. We identified 1258 genes that were upregulated and 1436 genes that were downregulated by miR-126-3p. Further comparison between the downregulated genes in HLMVEC and targets predicted by online databases including TargetScan and miRDB revealed 6 genes as potential direct targets of miR-126-3p. Our study is the first to report targets of miR-126-3p in HLMVEC and demonstrate the effect of miR-126 level alteration on the HLMVEC global transcriptome. These results add to the diverse functions of miR-126-3p in different endothelial cell types and provide basis for the development of cell type-specific treatment for lung diseases. Whole-genome expression profile were assessed on HLMVEC transfected with scramble control, miR-126-3p mimics, and miR-126-3p antisense hairpin inhibitors. Experiments were repeated in HLMVEC from 3 distinct donors as biological replicates.