Viral delivery of an RNA-guided genome editor for transgene-free plant germline editing

Genome editing is transforming plant biology by enabling precise DNA modifications. However, delivery of editing systems into plants remains challenging, often requiring slow, genotype-specific methods such as tissue culture or transformation. Plant viruses, which naturally infect and spread to most tissues, present a promising delivery system for editing reagents. But most viruses have limited cargo capacities, restricting their ability to carry large CRISPR-Cas systems. Here, we engineered tobacco rattle virus to carry the compact RNA-guided TnpB enzyme ISYmu1 and its guide RNA. This innovation allowed transgene-free editing of Arabidopsis thaliana in a single step, with edits inherited in the subsequent generation. By overcoming traditional reagent delivery barriers, this approach offers a novel platform for genome editing, which can greatly accelerate plant biotechnology and basic research.

基因组编辑（Genome Editing）可实现精准的DNA修饰，正深刻变革植物生物学研究领域。然而，将编辑系统递送至植物体内仍存在诸多挑战，通常需要依赖耗时且具基因型特异性的方法，如组织培养或遗传转化。植物病毒可自然侵染并扩散至植物多数组织，是极具潜力的编辑试剂递送载体。但多数病毒的装载容量有限，限制了其携带大型CRISPR-Cas系统的能力。本研究中，我们对烟草脆裂病毒（Tobacco Rattle Virus, TRV）进行工程化改造，使其携带紧凑的RNA引导型TnpB酶ISYmu1及其向导RNA（guide RNA）。该策略可单步完成无转基因的拟南芥（Arabidopsis thaliana）基因组编辑，且编辑位点可遗传至后续世代。通过突破传统编辑试剂递送的技术壁垒，该方法为基因组编辑提供了全新平台，有望大幅推动植物生物技术与基础研究的发展。