Cloning and Expression of Genome Segment 10 Gene Encoding Capsid Protein of Rice Black Streaked Dwarf Virus

The rice black streaked dwarf virus (RBSDV) and its RNA were isolated from infected maize plants from Shandong in China. The genome segment 10 (S10) gene encoding outer capsid protein was obtained by RT PCR and its sequence was compared with that in strains from Japan, Hubei and other areas in China. The homology of S10 between Shandong and Japanese strain was 92%, much lower than that with Chinese strains ranging from 97% to 98%. The expression vector pGEX S10 was constructed with S10 and pGEX 3X. When the E. coli strain BL21 harboring the pGEX S10 was induced by IPTG for 6 hours, SDS PAGE analysis showed that a 76 ku protein was expressed. This 76 ku protein was purified by Glutathione Sepharose 4B and western blot analysis. It is confirmed that the RBSDV S10 gene was expressed as GST fusion protein in E. coli .