Construction and identification of expression vectors of human immunodeficiency virus type I envelope with V3 loop modification

Objective: To construct expression vectors bearing HIV-1 ADA envelope (env) with V3 loop modification. Methods: Splicing by overlap extension (SOE) was used for modification of HIV-1 ADA V3 loop. Three pairs of primers were designed and overlap PCR was taken placed. Recombinant plasmid pSM-ADAΔV3 and pSM-ADAmV3 were obtained via ligation of the plasmid pSM and the PCR product. The recombinant plasmids were identified with PCR amplification and sequencing. Results: PCR products were obtained and correctly inserted into plasmid pSM. The recombinant plasmids were transformed into E.coli. Sequencing results had shown that the mutated env gene having correct nucleotide sequence was the expected fragment. Conclusions: Expression vectors of HIV-1 ADA env with V3 loop modification were constructed successfully, which provides basis for constructing pseudovirus and observing the effects of partial or complete deletion of V3 loop on the entry of viruses into target cells. Also, these expression vectors have an important implication in developing vaccine and drug.