Nucleotide sequence of the coat protein gene of Lettuce big-vein virus

A sequence of 1425 nt was established that included the complete coat prote in (CP) gene of Lettuce big-vein virus (LBVV), The LBVV CP gene encodes a 3 97 amino acid protein with a predicted M, of 44 486. Antisera raised agains t synthetic peptides corresponding to N-terminal or C-terminal parts of the LBVV CP reacted in Western blot analysis with a protein with an M,of about 48000, RNA extracted from purified particles of LBVV by using proteinase K , SDS and phenol migrated in gels as two single-stranded RNA species of app roximately 7.3 kb (ss-1) and 6.6 kb (ss-2). After denaturation by heat and annealing at room temperature, the RNA migrated as four species, ss-1, ss-2 and two additional double-stranded RNAs (ds-1 and ds-2). The Northern blot hybridization analysis using riboprobes from a full-length clone of the LB VV CP gene indicated that ss-2 has a negative-sense nature and contains the LBVV CP gene. Moreover, ds-2 is a double-stranded form of ss-2. Database s earches showed that the LBVV CP most resembled the nucleocapsid proteins of rhabdoviruses. These results indicate that it would be appropriate to clas sify LBVV as a negative-sense single-stranded RNA virus rather than as a do uble-stranded RNA virus.