Knockdown of α-enolase (Eno1) genes by RNAi does not increase the sensitivity of Propsilocerus akamusi to cadmium stress

α-enolase (Eno1) is a multifunctional enzyme which can as a stress protein under various environmental stresses. Recent researches also reported that Eno1 appears to have Cd2+ stress-related functions in cadmium tolerant plants. Our previous study inferred that the Eno1 gene might play an important role in the response of Propsilocerus akamusi to exogenous Cd2+. However, reports on the role of the Eno1 gene in coping with cadmium stress are still limited. In this study, we evaluated the roles of PaEno1 in the tolerance of P. akamusi to Cd2+ using RNAi technology and the response of recombinant proteins of PaEno1 in an E. coli expression system under Cd2+ stress. Our results showed that knockdown of PaEno1 did not increase but reduce the sensitivity of P. akamusi larvae to Cd2+ stress. However, bioassays showed the expression of recombinant PaEno1 protein in Rosetta cells enhanced the growth ability of E. coli under Cd2+ stress. These results suggested that overexpression of PaEno1 can significantly enhance the tolerance to heavy metal cadmium stresses in E. coli cells. However, knockdown of PaEno1 genes by RNAi does not increase the sensitivity of P. akamusi to cadmium stress.