Effect of tannic acid on glutathione-S-transferase activity and gene expression in Acyrthosiphon pisum

In this study, we aimed to determine the effects of tannic acid (2 g·L⁻¹) on glutathione-S-transferase (GST) activity and gene expression in pea aphids (Acyrthosiphon pisum). Specifically, we measured the changes in GST activity and GST gene expression in different tissues of pea aphids after 48 hours of tannic acid treatment. The results show that GST activity decreased following tannic acid (2 g·L^{− 1}) treatment. Conversely, GST gene expression was affected; compared to the control, seven GST genes were up-regulated in the head of pea aphids, of which ApGST104 and ApGSTX1 were upregulated approximately threefold. Moreover, ten GST genes were upregulated in the chest, of which ApGSTD6 was upregulated 6.4 times higher than the control. Ten GST genes were upregulated in the abdomen, of which ApGST101 and ApGST105 were upregulated approximately fivefold. Nine GST genes were upregulated in the midgut, of which ApGST105 was upregulated by 3.2 times. These results show that tannic acid affected GST gene expression in pea aphids, with some GST genes being significantly upregulated (P < 0.05). This result indicates that GST genes may play an important role in the metabolism of tannic acid in pea aphids.