Role of ubiquitin ligase Ring2 in DNA damage induced by benzoapyrene / 中华劳动卫生职业病杂志

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the role of ubiquitin ligase Ring2 in the DNA damage induced by benzo[a]pyrene (B[a]P).</p><p><b>METHODS</b>The expression of Ring2 in human bronchial epithelial (16HBE) cells was inhibited by small interfering RNA (siRNA) to obtain siRNA-Ring2 16HBE cells. The siRNA-Ring2 16HBE cells, as well as normal 16HBE cells, were exposed to B[a]P (0, 1, 2, 4, 8, 16, and 32 µmol/L) for 24 h; other siRNA-Ring2 16HBE cells and normal 16HBE cells were exposed to B [a]P (16 µmol/L) for 0, 1, 2, 4, 8, 12, and 24 h. The levels of DNA damage were evaluated by alkaline single cell gel electrophoresis assay.</p><p><b>RESULTS</b>After being treated with siRNA for 36 h, the siRNA-Ring2 16HBE cells showed a 72% decrease in Ring2 expression compared with normal 16HBE cells. The analysis of covariance showed that whether to be treated with siRNA and concentration of B[a]P had impacts on Olive tail moment (OTM) (P = 0.032 and P < 0.001); the adjusted mean of OTM was significantly higher in siRNA-Ring2 16HBE cells than in normal 16HBE cells. Whether to be treated with siRNA and B[a]P exposure time had impacts on OTM (P = 0.031 and P < 0.001); the adjusted mean of OTM was significantly higher in siRNA-Ring2 16HBE cells than in normal 16HBE cells.</p><p><b>CONCLUSION</b>The DNA of 16HBE cells with decreased Ring2 expression has increased susceptibility to B[a]P, which may be due to reduced H2A monoubiquitination following decrease in Ring2 expression.</p>