Abstract: Activity and related gene expression of adenylate cyclase (AC) were investigated in clam worm Perinereisaibuhitensis with body weight of 1.5-2.5 g exposed to benzo(a)pyrene [B(a)P] at a dose of 0.5, 5, 10, and 50 μg/L in a 1 L glass beaker, acetone solvent (100 μL/L) as a control and seawater as a blank control, for 4 days, 7 days, and 14 days to probe into the toxicity response P.aibuhitensis to xenobiotic pollutants. The full length cDNA of AC in P.aibuhitensis was cloned through rapid amplification of cDNA ends (RACE) method and the mRNA expression of AC in P.aibuhitensis exposed to B(a)P was detected by real-time fluorescence quantitative PCR. The results showed that the full length cDNA of the AC was 4900 bp with 127 bp 5′-untranslated region, 1536 bp 3′-untranslated region and 3237 bp open reading frame encoding 1078 amino acids. There were two conserved region of cyclase catalytic domain in the amino acid sequences. Alignment analysis showed that the P.aibuhitensis AC had 34% to 47% identity with AC in other organisms. B(a)P exposure induced an increase in mRNA expression of the AC, with the maximal mRNA expression of AC at 0.5 μg/L and 10 μg/L B(a)P at day 7, and the peake mRNA expression in 5 μg/L and 50 μg/L B(a)P at day 14. The enzyme linked immunosorbent assay (ELISA) analysis revealed that the AC activity was also induced by B(a)P exposure, with the maximal AC activity in 0.5, 5 μg/L and 50 μg/L B(a)P groups at day 4, then decrease in the activity of AC in those groups with time. The AC activity was found to be firstly inhibited, and then peaked at day 7 in 10 μg/L B(a)P group. The findings indicated that B(a)P affected the gene expression and enzyme activity of AC in clam worm.
2020, Vol. 35 
