THE COMPLETE NUCLEOTIDE-SEQUENCE OF BEAN YELLOW MOSAIC POTYVIRUS RNA

The complete nucleotide sequence of an Australian strain of bean yello w mosaic virus (BYMV-S) has been determined from cloned viral cDNAs. T he BYMV-S genome is 9 547 nucleotides in length excluding a poly(A) ta il. Computer analysis of the sequence revealed a single long open read ing frame (ORF) of 9 168 nucleotides, commencing at position 206 and t erminating with UAG at position 9 374-6. The ORF potentially encodes a polyprotein of 3 056 amino acids with a deduced Mr of 347 409. The 5' and 3' untranslated regions are 205 and 174 nucleotides in length res pectively. Alignment of the amino acid sequence of the BYMV-S polyprot ein with those of other potyviruses identified nine putative proteolyt ic cleavage sites. The predicted consensus cleavage site of the BYMV N Ia protease was found to differ from that described for other potyviru ses. Processing of the BYMV polyprotein at the designated proteolytic cleavage sites would result in a typical potyviral genome arrangement. The amino acid sequences of the putative BYMV encoded proteins were c ompared to the homologous gene products of twelve individual potyvirus es to identify overall and specific regions of amino acid sequence hom ology.