ANALYSIS OF THE NUCLEOCAPSID GENE OF LETTUCE NECROTIC YELLOWS RHABDOVIRUS

The complete nucleotide sequence of the nucleocapsid (N) gene of lettu ce necrotic yellows virus (LNYV), the type member of the genus Cytorha bdovirus of plant rhabdoviruses, has been determined from cDNA clones of both the viral genomic and messenger RNAs. The previously identifie d N gene was adjacent to the 3' leader RNA and began at position 91 fr om the 3' end of the LNYV genome. Analysis of the sequence showed that the N mRNA contained a 78-nt 5' untranslated region, followed by a 13 77-nt open reading frame (ORF) encoding a 459-amino-acid protein. This ORF was similar in size to the N protein ORFs of other rhabdoviruses. However, little if any direct sequence homology was found with N prot ein sequences of other rhabdoviruses. Short amino acid sequences were found to be conserved between the N proteins of LNYV and sonchus yello w net virus (SYNV), a member of the genus Nucleorhabdovirus of plant r habdoviruses. Among them, a sequence of 24 amino acids which was simil ar between LNYV and SYNV N proteins corresponded to a region with high homology between isolates of vesicular stomatitis virus and rabies vi rus N protein sequences, the type members of the genera Vesiculovirus and Lyssavirus of animal rhabdoviruses, respectively. (C) 1994 Academi c Press, Inc.