Identification and antioxidant characterisation of thioredoxin-like1 from Apis cerana cerana

Thioredoxins (Trxs) play a crucial role in maintaining redox homeostasis and protecting organisms against toxic reactive oxygen species. Compared with the well-studied Trxs in Mammalia, little is reported in insects. In this study, we isolated a Trx-like1 gene from Apis cerana cerana (AccTrx-like1), a single copy gene, and characterised its antioxidant activity. Quantitative real-time PCR and immunohistochemical assays revealed that AccTrx-like1 was most highly expressed in larvae and was localised primarily in the epidermis and brain tissue of adults. Expression analyses indicated that AccTrx-like1 expression is induced by both H2O2 and low temperatures. Moreover, catalase activity and malondialdehyde levels were inversely related to the expression levels of AccTrx-like1 in honeybee injected with H2O2 at 30 min. Taken together, these results suggest that AccTrx-like1 is an important antioxidant gene that is likely to play a role in preventing oxidative stress in A. cerana cerana.