Overexpression of microRNA miR-146a diminish the apoptosis ratio of the thymic stromal cell by inhibiting the expression of the target gene TRAF-6

Objective To explore the influence of microRNA miR-146a in the development and aging atrophy of thymus. Methods miR-146a was overexpressed in the thymic stromal cell (TSC) by transfection with miR-146a mimic.After 48 hours of the transfection, the miR-146a content was detected by reverse transcription polymerase chain reaction (RT-PCR). After 72 hours of the transfection, the protein level of target gene tumor necrosis factor receptor-associated factor 6(TRAF-6) was tested by Western Blot method and the apoptosis ratio of TSC was assayed by flow cytometry. Results The expression of miR-146a was significantly higher than those in the negative control group[(192.95±54.64) vs.1]P<0.05) after 48 hours of the transfection.The TRAF-6 protein level was decreased[(0.50±0.25)vs.1] and the apoptosis ratio[(13.90%±1.84%) vs.(22.83%±3.44%)] was diminished in the mimics group by comparing with the negative control group(both P<0.05). Conclusion Overexpression of miR-146a could diminish the apoptosis ratio of TSC by inhibiting the expression of the target gene TRAF-6. Key words: Thymus; Thymic stromal cell; miR-146a; Tumor necrosis factor receptor-associated factor 6; Apoptosis