Close similarity between genome structures of rice black-streaked dwarf and maize rough dwarf viruses

Abstract

The complete nucleotide sequences of rice blackstreaked dwarf virus (RBSDV) genome segments 8 ($8) and 7 ($7) were determined, and were found to have high sequence identities to the corresponding maize rough dwarf virus (MRDV) genome segments. RBSDV $8 and $7 consisted of 1927 and 2193 nucleotides, respectively. RBSDV $8 had a single long open reading frame (ORF)encoding 591 amino acids. RBSDV $7 had two nonoverlapping ORFs encoding 362 (ORF1) and 309 (ORF2) amino acids. The two ORFs of RBSDV $7 were inserted separately into an Escherichia coil expression vector (pKK223-3). When they were expressed in E. coli cells, the products of both ORFs migrated identically at an apparent M r of 40K. High nucleotide sequence identity was observed between RBSDV $7 and MRDV $6 (85 %), and between the terminal regions of RBSDV $8 and MRDV $7. In addition, RBSDV $7 and MRDV $6 showed 91% (ORF1 product) and 85% (ORF2 product) amino acid sequence identities.

Detection and assignment of proteins encoded by rice black streaked dwarf fijivirus S7, S8, S9 and S10.

“…et al, 1991) ; a similar dicistronic structure has been found in RBSDV S7 (Azuhata et al, 1993) and MRDV S8 (Marzachı! et al, 1996).…”

“…cDNA clones were generated from either viral transcripts (Azuhata et al, 1993) or genomic dsRNA (Uyeda et al, 1990) and those from S9 were selected by hybridization using S9 as a probe. One clone that covered about 80 % of S9 from the 3h end and four clones that covered the 5h-terminal region were used for sequencing.…”

“…At present, little is known of the proteins encoded by the 10 fijivirus genomic double-stranded RNA (dsRNA) segments (S1-S10), including those of RBSDV, and the nucleotide sequences of only some of them have been determined (Uyeda et al, 1990 ;Azuhata et al, 1993 ;Marzachı! et al, 1991Marzachı!…”

Taxonomic characteristics of fijiviruses based on nucleotide sequences of the oat sterile dwarf virus genome.

“…Azuhata et al, 1992). However, RBSDV and MRDV belong to the same Fijivirus group and are believed to be closely related (Azuhata et al, 1993). To determine whether these terminal sequences represent a genus-specific characteristic, fijiviruses from groups other than group 2 should be analysed.…”

Nucleotide sequence of Nilaparvata lugens reovirus genome segment S8 coding for the major outer capsid protein

“…For example, the amino acid sequence identities between the major outer capsid proteins (MOCPs) range from 48 to 56 % (Omura et al, 1989;Xu et al, 1989;Noda et al, 1991 b). In the Fijivirus genus, the nucleotide sequences of MRDV genome segment 6 ($6) (Marzachi et al, 1991) and RBSDV S10 (Uyeda et al, 1990), $8 and $7 (Azuhata et al, 1993) have been reported, but those of their MOCPs are unknown. We previously reported the nucleotide sequence ofNLRV S10 (Noda et al, 1994).…”