Beyond species and spatial boundaries: Enabling long-distance gene silencing in plants via guanidinium-siRNA...

RNA interference (RNAi) has been widely used in agriculture. However, it is well accepted that common methods of plant RNAi are species-dependent and lack systematic efficiency. This study designed a thiolated siRNA nanoparticle, guanidinium (Gu⁺)-containing disulfide assembled siRNA (Gu⁺-siRNA), demonstrating remarkable species independence and efficient systemic gene silencing across different plant species. Our results indicate that this approach effectively utilizes the plant vascular system to deliver siRNA, enabling long-distance gene silencing across both monocot and dicot plants, such as rice and Arabidopsis. By applying this method, we successfully targeted and silenced key genes like STM, WER, MYB23, GD1, EIL1, and EIL2, which regulate plant development and enhance salt tolerance. This delivery system significantly expands the application of RNAi technology across different plants, serving as a valuable tool for advancing agricultural biotechnology, enhancing crop resistance, and improving agricultural productivity, while aligning with global goals for sustainable food production and crop improvement.