Selective control of plant gene expression using artificial microRNAs and synthetic trans-acting small interfering RNAs

The ability to selectively control plant gene expression is key to engineer crops with improved traits to face the agricultural challenges of the next years. During the last decade, RNA interference (RNAi) has emerged as a potent technology to selectively turn off gene expression in plants. Artificial microRNAs (amiRNAs) and synthetic trans-acting small interfering RNAs (syn-tasiRNAs) are two classes of RNAi-based strategies extensively used for specific gene silencing in plants for both basic research and biotechnology purposes. However, current methods to design and produce amiRNAs or syn-tasiRNAs are not always well adapted for cost-effective, large-scale production, or for multiplexing to specifically suppress multiple targets simultaneously. We will describe our recent advances in developing i) the P-SAMS (Plant small RNA maker suite) web tool for the automated design of amiRNAs and syn-tasiRNAs, and ii) simple, fast and cost-effective cloning methods with high-throughput capability to generate amiRNA and multiplexed syn-tasiRNA constructs for efficient gene silencing in both monocot and eudicot species. P-SAMS designed amiRNAs and syn-tasiRNAs were validated in transgenic plants that exhibited the expected phenotypes predicted by loss of target gene function.