Search

Environmental pollution has gained negative attention in recent years. The pesticides and heavy metals are top list of environmental toxicants directly endangering the survival and development of Apis cerana cerana. Cyclin-dependent kinases (CDKs) are heteromeric serine/threonine kinases that participate in cell cycle regulation and have a vital role in pesticide and heavy metal stress in Apis cerana cerana. In this experiment, we filtered out CDK8 gene from Apis cerana cerana (AccCDK8) and investigated its functions of pesticide and heavy metals resistance. Sequence analysis indicated that AccCDK8 is highly homologous to multiple CDK8s and contains a highly conserved CDK active site sequence. Phylogenetic analysis showed that AmCDK8 and AccCDK8 were closely related evolutionarily in Apis mellifera. Transcriptome analysis revealed that AccCDK8 expression was differentially affected after exposure to pesticide and heavy metal stresses. This indicates that AccCDK8 has a significant role in the resistance of Apis cerana cerana to pesticide and heavy metal stresses. It has implications for studying the function of CDK in other insects in response to stress. [Display omitted] • Pesticides and heavy metals affect the survival of Apis cerana cerana. • CDK8 takes part in the oxidative stress response of Apis cerana cerana. • CDK8 is involved in the growth and reproduction of Apis cerana cerana. • AccCDK8 plays an important role in pesticide and heavy metals stresses. • We highlight the effects of some pesticides on the health of Apis cerana cerana. [ABSTRACT FROM AUTHOR]

Carboxylesterases (CarEs) play vital roles in metabolising different physiologically important endogenous compounds and in detoxifying various harmful exogenous compounds in insects. Multiple studies of CarEs have focused on pesticide metabolism in insects, while few studies have aimed to identify CarE functions in oxidative resistance, particularly in Apis cerana cerana . In this study, we isolated a carboxylesterase gene, esterase FE4, from Apis cerana cerana and designated it towards an exploration of its roles as an antioxidant and in detoxification. We investigated AcceFE4 expression patterns in response to various stressors. A quantitative real-time PCR analysis revealed that AcceFE4 was up-regulated by H 2 O 2 , imidacloprid, and paraquat, and was down-regulated by 4 °C, UV radiation, CdCl 2 , and HgCl 2 . Additionally, the protein expression of this gene was down-regulated at 4 °C and up-regulated by H 2 O 2 . Disc diffusion assays showed that the AcceFE4 recombinant protein-expressing bacteria had a smaller killing zone than the control group with the paraquat, HgCl 2 and cumyl hydroperoxide treatments. Moreover, when the gene was knocked down by RNA interference, we observed that multiple oxidant genes (i.e., AccSOD , AccGST , AccTrx , AccMsrA, and others) were down-regulated in the knockdown samples. Superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activity levels were reduced in the knockdown samples relative to the control group. Finally, we measured the enzyme activity of carboxylesterase and found that the enzyme activity was also reduced in the silent samples. Together, these data suggest that AcceFE4 may be involved in the oxidative resistance response during adverse stress. [ABSTRACT FROM AUTHOR]