Enhanced competitiveness of tomato bushy stunt virus defective interfering RNAs by segment duplication or nucleotide insertion

Abstract

We have analyzed atypical tomato bushy stunt virus defective interfering (DI) RNA species which accumulated during a passage series in protoplasts. We present a rationale for the order of appearance of these molecules and show, using competition assays, that either segment duplication or single nucleotide insertion can enhance DI RNA competitiveness. Possible mechanisms for the introduction of the modifications observed in these DI RNAs are discussed.