Abstract:
[Objective] To investigate the association between DNA damage and expression of mono-ubiquitinated histone H2A in human bronchial epithelial cells (16HBE) exposed to benzo[a]pyrene (B[a]P).
[Methods] The 16HBE cells collected at the logarithmic phase of growth were exposed to B[a]P at the concentration of 2μmol/L for 0, 1, 2, 4, 8, 12, 24 and 48 h respectively. DNA damage was determined by comet assay and expressed as olive tail moments (OTM). Protein expression was detected by Western-blot.
[Results] The results of comet assay showed that the OTM values increased with exposure time and a significant in crement was found as compared with the control group (P<0.01). After exposed to 2μmol/L B[a]P for 2 h, the mono-ubiquitination levels of histone H2A increased significantly when compared with the control group (P<0.01). The regression analysis showed a significant correlation between OTM and the levels of mono-ubiquitinated histone H2A, and the determination coefficient was 0.910 (P<0.01).
[Conclusion] The findings suggest a close correlation between DNA damage and the levels of mono-ubiquitinated histone H2A in 16HBE cells exposed to B[a]P.