CDNA cloning and sequence analysis of genome segments S8 from rice black-streaked dwarf virus

Abstract

Genome segments S8 of two Chinese isolates of rice black streaked dwarf virus (RBSDV), one from Zhejiang Province and another from Hebei Province, were amplified by RT PCR and sequenced. Both segments consisted of 1936 nts in full length (EMBL accession numbers were AJ297431 and AJ297432, respectively) and contained only one big open reading frame which encoded a polypeptide with molecular weight of 68kD. The two Chinese isolates shared 94.0% and 96.5% identity at nucleotide and amino acid level, respectively. They shared 94.5- 94.9% and 92.5-92.9% homology with S8 of RBSDV Japanese isolate at nucleotide and amino acid level, respectively; shared 85.1-87.6% and 91.7-91.9% homology with S7 of Italian MRDV (maize rough dwarf virus).