Abstract: Baculovirus PP31 is a phosphoprotein that could combine with DNA. The pp31 gene presents in all of the genomes of lepidopteran baculoviruses sequenced to date. In this study, Plutella xylostella pp31 gene was PCR-amplified and cloned into an expression vector pET28a, and transformed into the E. coli BL21（DE3）. In the transformed bacterial cells, induced by IPTG, a His-tagged PP31 protein with a size of 29 kD was expressed, which was purified using ProbondTM resin. Polyclonal antibodies against PlxyGV PP31 were prepared by immunizing a New Zealand rabbit with the purified his-tagged PP31. Western blot analysis showed that the antiserum had high titer and specificity and could be used in study of PP31.

Key words: Plutella xylostella granulovirus（PlxyGV）, PP31, Prokaryotic expression, Polyclonal antibody