MiRNA‐27a decreases ultraviolet B irradiation‐induced cell damage

MiRNAs were involved in the various biological process through mediating the posttranscriptional gene silencing. The abnormal expression of miRNAs is also involved in various disorders. Our previous study showed that miRNA‐27a (miR‐27a) was upregulated after ultraviolet B (UVB) irradiation. However, the function of miR‐27a in UVB‐induced cell damage is still unclear. In this study, we used the miR‐27a overexpression and knockdown lentivirus to transfect UVB irradiated HaCaT cell line and observed the influence of miR‐27a on UVB irradiated damages in cells. We found that miR‐27a removed cyclobutane pyrimidine dimers (CPDs) and decreased the cell apoptosis after UVB radiation. Further studies showed that miR‐27a directly decreased the expression and luciferase activity of target genes transactive response DNA‐binding protein (TARDBP) and apoptotic protease activating factor‐1 (APAF‐1). In conclusion, miR‐27a can inhibit CPDs, reduce the cell apoptosis and down‐regulate its target genes TARDBP and APAF‐1 induced by UVB irradiation in HaCaT cells. It is indicated that miR‐27a may serve as a target for UVB irradiation protection. The effects of miR‐27a on UVB irradiation‐induced CPD formation in Hacat cells. A, CPD formation was measured by immunofluorescence (Green). DAP I (blue) was used to stain the nucleus. B, Dot blot was used to the CPD formation.