Nucleotide sequence of the S and M RNA segments of a Groundnut bud necrosis virus isolate from Vigna radiata in India.

Nucleotide sequence of the S and M RNA segments of a Groundnut bud necrosis virus isolate from Vigna radiata (mungbean isolate, GBNV-MB) was determined and compared with another isolate from Arachis hypogaea (groundnut isolate, GBNV-type). Comparative sequence analysis revealed that the genome organization of the S and M RNA segments of both GBNV-MB and GBNV-type isolates was similar. However, considerable differences were observed in their intergenic regions (IGRs) and the glycoprotein precursors (Gn/Gc) of the M RNA segments. M RNA IGRs of GBNV-MB and GBNV-type isolates differed in size by 14 nucleotides. This difference was of 75 nucleotides in another GBNV isolate from Lycopersicon esculentum (tomato). Sequence comparison of the M RNA IGRs of GBNV isolates from mungbean, groundnut and tomato from India revealed 56-89% sequence identity. The topology of Gn/Gc revealed the presence of both N-glycosylation (5) and O-glycosylation (1) sites in GBNV-MB isolate, whereas only N-glycosylation sites (4) were present in GBNV-type isolate.