THE NUCLEOTIDE-SEQUENCE AND GENOME STRUCTURE OF MUNG BEAN YELLOW MOSAIC GEMINIVIRUS

Complete nucleotide sequences of the infectious cloned DNA components (DNA 1 and DNA 2) of mung bean yellow mosaic virus (MYMV) were determi ned. MYMV DNA 1 and DNA 2 consists of 2,723 and 2,675 nucleotides resp ectively. DNA 1 and DNA 2 have little sequence similarity except for a region of approximately 200 bases which is almost identical in the tw o molecules. Analysis of open reading frames revealed nine potential c oding regions for proteins of mol. wt. > 10,000, six in DNA 1 and thre e in DNA 2. The nucleotide sequence of MYMV DNA was compared with that of bean golden mosaic virus (BGMV), tomato golden mosaic virus (TGMV) and African cassava mosaic virus (ACMV). The 200-base region common t o the two DNAs of each virus had little sequence similarity, except fo r a highly conserved 33 36 base sequence potentially capable of formin g a stable hairpin structure. The potential coding regions in the MYMV DNAs had counterparts in the BGMV, TGMV and ACMV, suggesting an overa ll similarity in genome organization, except for absence of 1L3 in MYM V DNA 1. The most highly conserved ORFs, MYMV 1R1, BGMV 1R1, TGMV 1R1 and ACMV 1R1, are the putative genes for the coat proteins of MYMV, BG MV, TGMV and ACMV, respectively. MYMV 1L1 has also a high degree of se quence similarity with BGMV 1L1, TGMV 1L1 and ACMV 1L1.