Detalle de: Plant Virus Genome Is Shaped by Specific Dinucleotide Restrictions That Influence Viral Infection

Dinucleotides (combinations of two consecutive nucleotides) are not randomly present in RNA viruses; in fact, the presence of CpG and UpA is significantly repressed in their genomes. Although the meaning of this phenomenon remains obscure, recent studies with animal-infecting viruses have revealed that their low CpG/UpA frequency prevents virus restriction via a host antiviral system that recognizes, and promotes the degradation of, CpG/UpA-rich RNAs. Whether similar systems act in organisms from other life kingdoms has been unknown. To fill this gap in our knowledge, we built several synthetic variants of a plant RNA virus with deoptimized dinucleotide frequencies and analyzed their viral fitness and genome adaptation. In brief, our results inform us for the first time about an effective dinucleotide-based system that acts in plants against viruses. Remarkably, this viral restriction in plants is reminiscent of, but not identical to, the equivalent antiviral response in animals.