The nucleotide sequence of Indian peanut clump virus RNA 2: sequence comparisons among pecluviruses

The RNA-2 molecule of an isolate of the L serotype of Indian peanut clump v irus (IPCV) was shown to consist of 4290 nucleotides with five open reading frames (ORF). The arrangement of the ORFs resembled that in RNA-2 of Peanu t clump virus (PCV) from West Africa. The proteins encoded by the ORFs in I PCV-L RNA are between 32% and 93% identical to those encoded by PCV RNA. Pa rtial sequence data for the RNA-2 of isolates of the H and T serotypes of I PCV show that the coat and P40 proteins encoded by the 5'-most ORFs of RNA- 2 of IPCV-L, IPCV-H and IPCV-T are as similar to each other as any is to th e corresponding proteins of PCV. A conserved motif 'F-E-x(6)-W' is present near the C-termini of the coat proteins of all three IPCV serotypes and of PCV, as it is in the coat proteins of other viruses that have rod-shaped pa rticles, such as Tobacco mosaic virus and Tobacco rattle virus. The results support the distinction of IPCV and PCV as separate virus species, but als o raise the question of how the serotypes of IPCV should be classified.