Cloning, sequencing and expressing of coat protein gene of grapevine leaf roll associated closterovirus.

GLRaV dsRNA, about 18 kb, was extracted from the phloem of grapevine infected with GLRaV in China and the cDNA fragment (ca.1.0 kb) was amplified by RT PCR using dsRNA as template. This product was inserted into pBluescript II SK vector. Analysis of nucleotide and deduced amino acid sequence between this isolate and GLRaV 3, an American isolate, showed 99.15% and 98.09% similarity, respectively. Expression of GLRaV coat protein gene in E.coli showed a 35 kDa unique protein as expected. Result of Western Blot analysis also showed that there is close serum relationship between GLRaV CP Chinese isolate and that of American isolate.