Abstract: Grapevine virus A (GVA) is a typical member in genus Vitivirus. The virus has been broadly discovered in vineyard around the world. Using an ELISA detection technology, four virus species were identified in 6 out of 10 shoot samples of Japanese hybrid grape, c.v. Fujiminori, Reverse Transcription-Polymerase Chain Reaction (RT-PCR) was used to amplify a complete coding sequence of the GVA coat protein (CP) from the virus-positive shoot samples. The CP gene, specified as the Sichuan isolate "SL10", contains 597 base pairs in length. The "SL10" CP gene was compared with other 15 GeneBank-collected CP genes, isolated from different geographic origins. Phylogenetic analysis clearly clustered the 16 CP genes into two distinguished groups. Group I contains only 3 members. The nucleotide identities among the 3 members range from 75.9% to 80.1%; whereas group II holds the rest 13 members. The nucleotide identities within the members in this group vary from 84.4% to 99.5%. The isolated CP gene was cloned into a prokaryotic expression vector and transformed into an E. coli strain BL21. After induced by IPTG, the CP gene was highly expressed in the E. coli.

Key words: Grapevine Virus A, ELISA, RT-PCR, coat protein gene, prokaryotic expression