Minimal small RNA precursors unlock virus-based precision RNAi.

Artificial small RNAs (art-sRNAs) mediate highly specific RNAi in plants, but their broader use has been constrained by long precursor architectures and dependence on transgenic delivery. Recent work shows that accurate and efficient art-sRNA biogenesis can be achieved using precursors of minimal size rather than full-length endogenous scaffolds, without compromising silencing efficacy. We discuss how minimal art-sRNA precursors represent a versatile platform for precision RNAi and, critically, unlock RNA viruses as stable, programmable platforms for the production of highly specific art-sRNAs. In other words, minimal art-sRNA precursors transform RNA viruses from generators of heterogeneous small RNA populations into nontransgenic, programmable vectors that deliver defined art-sRNAs for precision gene silencing and antiviral protection.