MiR-449b regulates HDAC1 mRNA and protein expression.

<div><p>(A) HDAC1 and IFNβ are regulated by influenza-induced miRNAs. Histograms illustrating the average microarray signal for HDAC1 (left) and IFNβ (right) in the presence or absence of miRNAs described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0076560#pone-0076560-g003" target="_blank">Figure 3</a>.</p> <p>(B) Depiction of the binding site for miR-449b and other family members in the 3’ UTR of HDAC1 mRNA as determined by TargetScan algorithm [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0076560#B43" target="_blank">43</a>]..</p> <p>(C) miR-449b directly targets the HDAC1 3’ UTR. A549 cells were transfected with 200ng of luciferase reporter gene containing either the wild type or mutant HDAC1 3’ UTR in the presence or absence of 50nM non-targeting control miRNA mimic (NTC) or miR-449b specific mimic (miR-449b) as indicated. Twenty-four hours after transfection, luciferase activity was measured.</p> <p>(D) miR-449b decreases HDAC1 mRNA level. A549 cells were either untreated (UNT), transfected with 50nM non-targeting control miRNA mimic (NTC) or transfected with 50nM miR-449b specific mimic (miR-449b). Twenty-four hours after transfection, the abundance of HDAC1 mRNA and miR-449b were determined by RT-qPCR.</p> <p>(E) miR-449b decreases HDAC1 protein level. In parallel samples, the abundance of HDAC1 and GAPDH protein was determined by immunoblotting with specific antisera.</p> <p>Statistical analysis was performed by a two-tailed t-test (p-value<0.05=*, p-value<0.01=**, p-value<0.001=***).</p>