Abstract: 【Objective】The objectives of this study are to prepare the monoclonal antibody against ecdysone receptors protein and clarity the response of AlEcR-A under exogenous ecdysterone hormone (20E) in Apolygus lucorum.【Method】The vector containing AlEcR-A was double enzyme restricted by Nde Iand Xba I, then the cDNA identified by sequencing was constructed to pCzn1 vector and transformed into Arctic express of E. coli. The target recombinant protein has over expressed and has been purified by using Ni-NTA agarose. BALB/c mice were immunized with the purified recombinant fusion protein. The spleen cells of mouse were fused with SP2/0 cells. The specificity of hybridoma cell line was characterized by ELISA and Western blot analysis. Finally, the mRNA relative expression and protein content of AlEcR-A treated with exogenous 20E by RT-PCR and Western blot were analyzed, respectively.【Result】The recombinant plasmid pCzn1-AlEcR-A was high-efficient expression in Arctic express when induced by 37℃ and 5.0 mmol·L^-1 IPTG. The 55 kD target protein from the strain containing AlEcR-A was obtained by the Ni-NTA agarose. One hybridoma cell line, named 8H7, was obtained and characterized by ELISA and Western blot analysis, which could specifically combine with the total protein of A. lucorum and recombinant protein of AlEcR-A. By using RT-PCR and Western blot analysis, both the mRNA relative expression and protein content of AlEcR-A were remarkably increased after treating with 20E which compared with control.【Conclusion】the high specificity monoclonal antibody of AlEcR-A protein was obtained, and 20E could induce the mRNA and protein expressions of AlEcR-A.

Key words: Apolygus lucorum, ecdysone receptor, 20E, monoclonal antibodies, expression level