Molecular cloning and characterization of the genome of wound tumor virus: a tumor-inducing plant reovirus.

The double-stranded RNA genome of the tumor-inducing plant pathogen, wound tumor virus, was converted to double-stranded DNA and cloned into plasmid pBR322. Multiple apparent full-length copies of 9 of the 12 wound tumor virus genome segments were identified. The entire sequence of cloned genome segment S12, the smallest of the genome segments, was determined. This genome segment was found to be 851 nucleotides in length and to possess a single long open reading frame that extends 178 codons from the first AUG triplet (residues 35-37): information sufficient to encode a protein of the size estimated for the smallest of the previously identified wound tumor virus primary gene products, Pns 12. Sequence data obtained from analysis of cloned cDNA copies of several genome segments and from direct analysis of the 3' termini of the double-stranded genome RNAs revealed that each wound tumor virus genome segment possesses the common terminal sequences: (+) 5'GGUAUU ... UGAU 3' (-) 3'CCAUAA ... ACUA 5'.