In vitro recombinant yeast assay reveals the binding of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and aryl hydrocarbon receptor (AhR) from scallop Chlamys farreri

We developed an in vitro recombinant yeast assay to investigate whether five representative xenobiotic ligands including 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), β-naphthoflavone (BNF), benzo[a]pyrene (B[a]P), chrysene (CHR) and phenanthrene (PHE) can bind with the AhR of the scallop Chlamys farreri (CfAhR). The plasmid pGBKT7-CfAhR and pGADT7-XRE were transformed to yeast (Saccharomyces cerevisiae,Y187) to construct the recombinant yeast Y187CfAhR/XRE, and the report gene product β-galactosidase activity was measured after Y187CfAhR/XRE was induced by TCDD, BNF, B[a]P, CHR and PHE with a series of concentrations. Results not only demonstrated that the β-galactosidase could be detected in Y187CfAhR/XRE without any treatment, but also reflected that CfAhR can interact with the XRE sequence. β-galactosidase activities were significantly induced in 1–100 nM TCDD groups, indicating that TCDD can bind with CfAhR. This provides evidence for the binding capacity of TCDD and invertebrate AhR, while no evidence was found to prove that other four compounds could bind with CfAhR in our experiments.