Abstract:Recombinant plasmid pET-P25 was constructed by ligating movement protein (P25) gene of Potato virus X (PVX) into the expression vector pET-30a and then transferred into E.coli BL21 (DE3) pLysS. The results of SDS-PAGE showed that 29 kD specific fusion protein was produced after induction by IPTG. The fusion protein was injected into mice to prepare antiserum after being purified crudely. And the titer was determined to be 1∶ 4000. The antiserum has special response with PVX (P/N>2) compared with no response with PVY and TMV. Using this antiserum, we can examine the infected leaves by PVX and PVX-P25 transgenic tobacco. And the result showed that P25 gene had been expressed and translated to protein in some transgenic plants.