THE COMPLETE NUCLEOTIDE-SEQUENCE OF THE S-RNA OF A NEW TOSPOVIRUS SPECIES, REPRESENTING SEROGROUP-IV

A tospovirus isolate Tospo-To, recently shown to be serologically rela ted to some Taiwanese, Japanese, and Indian tospovirus isolates, was p urified and its S RNA segment was cloned and sequenced. The complete n ucleotide sequence of the S RNA, 3,536 nucleotides, contained inverted terminal repeats and two large open reading frames in ambisense orien tation, separated by an intergenic region that is significantly larger than those of hitherto known tospoviruses. Amino acid sequence compar isons revealed 16 and 33% identities with the Ns(s) and N protein of t omato spotted wilt tospovirus for the viral sense and virus-complement ary reading frames, respectively. In contrast to other tospoviruses, a dditional putative open reading frames besides those for N and Ns(s) h ave been detected in the nucleic acid sequence of this new tospovirus isolate. The sequence comparisons for N protein amino acid sequences o f several different tospovirus species and isolates indicated Tospo-To should be regarded as a new species in the genus Tospovirus as has al ready been suggested from serological data.