MiR-155 Negatively Regulates c-Jun Expression at the Post-transcriptional Level in Human Dermal Fibroblasts in vitro: Implications in UVA Irradiation-induced Photoaging

Cellular Physiology and Biochemistry

关键词: c-Jun;    miR-155;    Photoaging;    Dermal fibroblasts;    Ultraviolet A;   

DOI  :  10.1159/000338488

学科分类：分子生物学，细胞生物学和基因

来源: S Karger AG

【 摘 要 】

Objective C-Jun plays a critical role in ultraviolet A (UVA) irradiation-induced photoaging. The exact mechanisms by which UVA irradiation up-regulates c-Jun expression in human dermal fibroblasts (HDFs) are still not completely understood. We undertook this study to investigate whether microRNA-155 (miR-155) directly regulates the expression of c-Jun in HDFs in vitro. Methods Expression of c-Jun mRNA and protein and miR-155 in UVA-irradiated HDFs were detected using quantitative real-time RT-PCR and Western blotting. Luciferase reporter assays were performed to examine whether a miR-155 binding site in the 3′-untranslated region (3′-UTR) of the c-Jun gene is responsible for miR-155-mediated c-Jun regulation in HEK293A cells, and expression of c-Jun mRNA and protein in UVA non-exposed and exposed HDFs trasfected with a miR-155 mimic or a miR-155 inhibitor was detected by quantitative real-time RT-PCR and Western blotting. Results Expression of miR-155 was markedly reduced and that of c-Jun mRNA and protein was significantly up-regulated in UVA-irradiated HDFs. Luciferase reporter assays indicated that c-Jun is a direct target of miR-155 in HEK293A cells. In both UVA non-exposed and exposed HDFs, miR-155 mimic decreased c-Jun protein levels, while miR-155 inhibitor increased c-Jun protein levels, but both had no effect on c-Jun mRNA expression, which suggest that miR-155-induced c-Jun inhibition occurs at the post-transcriptional level. Conclusions Our results demonstrate that miR-155 directly controls c-Jun expression in HDFs at the post-transcriptional level and might function as a protective miRNA in HDFs.

【 授权许可】

CC BY-NC-ND