Objective   To construct a prokaryotic expression vector for human apurinic/apyrimidinic endonuclease (hAPE1) genes

to purify its fusion protein

and to study its activity.     Methods   PCR-amplified hAPE1 gene was cloned into the prokaryotic expression vector pET28a for recombinant plasmid pET28a-hAPE1. Then this recombinant plasmid was transformed into E.coli BL21 (DE3) and induced to express hAPE1 fusion protein with IPTG. The expressed hAPE1 fusion protein was identified by SDS-PAGE and Western blot

and purified by affinity chromatography with His column. Immunogenicity and activity of hAPE1 fusion protein were analyzed by Western blot and EMSA.     Results   DNA sequencing

SDS-PAGE

and Western blot showed pET28a-hAPE1 was constructed correctly. High expression of hAPE1 fusion protein by pET28a-hAPE1 was found in E.coli BL21 (DE3). The hAPE1 fusion protein

being of immunogenicity

AP repair

and redox function

could be purified via affinity chromatography with His column.     Conclusion   The prokaryotic expression vector of pET28a-hAPE1 vector was successfully constructed. The hAPE1 fusion protein could be highly expressed in E.coli BL21 (DE3) and successfully purified

which is significant for the elucidation of the biological characters of APE1 and the preparation of antibodies in the future study.