Cloning and Expression of Ubiquitin Gene of Helicoverpa armigera Single-nucleocapsid Nucleo- polyhedrovirus and its Antiserum Preparation

Baculoviruses and entomopoxvirus are the viruses which have been reported so far having ubiquitin gene. The ubiquitin gene of Helicoverpa armigera single-nucleocapsid nucleopolyhedrovirus(HaSNPV) was amplified by PCR. Nucleotide analysis showed that it was 252bp,encoded 83 amino acids with a predicted size of 9.24kDa. The PCR product containing ubiquitin gene was inserted into pET-28a expressive vector. The Ubi-His-tag fusion protein was expressed in E.coli BL21(DE3).The fusion protein was identified by Western blotting with His-tag antibody. The expressions conditions including the contentrations of IPTG and the inducing times were optimized to achieve optional expression. The antibody anti the HaSNPV ubiquitin was produced in rabbit with purified ubiquitin fusion protein , and further study on the function of HaSNPV UBI is underway.