THE NUCLEOTIDE-SEQUENCE OF THE COAT PROTEIN GENES OF SATSUMA DWARF VIRUS AND NAVEL ORANGE INFECTIOUS MOTTLING VIRUS

The sequence of the 3'-terminal 4320 and 2409 nucleotides were determi ned for RNA2 of satsuma dwarf virus (SDV) and navel infectious mottlin g virus (NIMV). Both sequences contained a part of a long open reading frame which encodes larger and smaller coat proteins (CPs) at the 3'- terminus followed by a 3' non-coding region upstream of a poly(A) tail . Amino acid sequence identity for larger and smaller CPs ranged 81-84 % and 68-78%, respectively, among SDV, NIMV and the previously sequenc ed citrus mosaic virus (CiMV). No significant sequence similarity was found between the CPs of SDV or NIMV and those of the como-, nepo- or other viruses. The nucleotide sequence identity of the 3' non-coding r egion of RNA2 were 68%-78%. among SDV, CiMV and NIMV. These results su ggest that SDV, CiMV and NIMV are distinct, though related, viruses. T hey may be assigned as members of the new genus, which is close to the genera of Comovirus and Nepovirus.