The expression characteristics of vitellogenin (VTG) in response to B(a)p exposure in polychaete Perinereis aibuhitensis

In order to investigate the endocrine toxicity of B(a)p to marine polychaete Perinereis aibuhitensis, vitellogenin (VTG) cDNA from the P. aibuhitensis was isolated, recombinated and expressed for the first time. The full length P. aibuhitensis vitellogenin gene (PaVTG) was 5 325 bp, and encoded 1 692 amino acids. It contained the vitellogenin_N domain of unknown function (DUF1943), a von Willebrand factor type D domain, as well as a conserved KALGNAG motif. The expression of VTG gene and protein were mainly up-regulated after exposed to B(a)p at transcriptional and translational levels. PaVTG gene expression did not change significantly at day 4. At day 7 PaVTG expression was up-regulated in 0.5 μg/L and 5 μg/L B(a)p group. At day 14 PaVTG was significantly up-regulated in 0.5–10 μg/L B(a)p. The protein expression of PaVTG in 0.5 μg/L and 10 μg/L B(a)p group was up-regulated with time prolonging, but the expression in 5 μg/L and 50 μg/L B(a)p group exhibited first increased and then decreased trend. With the increasing of B(a)p concentration PaVTG mRNA and protein expression both firstly increased then decreased. In contrast to B(a)p exposure, estradiol did not induce PaVTG gene and protein expression, until late times of exposure (14 d). Overall, the results in this study indicate that PaVTG could be used as a potential indicator of the effects environmental estrogenic compounds.