PEANUT BUD NECROSIS TOSPOVIRUS-S RNA - COMPLETE NUCLEOTIDE-SEQUENCE, GENOME ORGANIZATION AND HOMOLOGY TO OTHER TOSPOVIRUSES

The complete nucleotide sequence of the S RNA of peanut bud necrosis v irus (PBNV) has been determined. The RNA is 3057 nucleotides in length , contains inverted repeats and two open reading frames (ORFs) with an ambisense coding strategy that are separated by an A + U-rich interge nic region. One ORF (1 320 nucleotides in the viral sense strand) enco des a Mr 49.5 kDa protein, identified as the nonstructural (NSs) prote in based on similarity to published tospovirus sequences. The second O RF (831 nucleotides in virus complementary strand) encodes a Mr 30.6kD a protein. This protein was identified as the nucleocapsid (N) protein based on sequence similarities. Amino acid sequence comparison of N a nd NSs proteins revealed identities of 22-34% with the reported tospov irus isolates of serogroups I, II, and III, whereas it had 82-86% iden tity with viruses in serogroup IV, watermelon silver mottle virus (WSM V) and tomato isolate of peanut bud necrosis virus (PBNV-To). Two subg enomic RNA species detected in PBNV infected tissue corresponded to th e predicted sizes (1.65 and 1.4 kb) of the NSs and N mRNAs. The data p resented show conclusively that PBNV should be included in serogroup I V, along with WSMV and PBNV-To.