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

Weiss, T.; Kamalu, M.; Shi, H.; Li, Z.; Amerasekera, J.; Adler, B. A.; Song, M.; Vohra, K.; Wirnowski, G.; Chitkara, S.; Ambrose, C.; Steinmetz, N.; Sridharan, A.; Sahagun, D.; Banfield, J.; Doudna, J.; Jacobsen, S. E.

doi:10.1101/2024.07.17.603964

bioRxiv · 10.1101/2024.07.17.603964

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

Weiss, T.·Kamalu, M.·Shi, H.·Li, Z.·Amerasekera, J.·Adler, B. A.·Song, M.·Vohra, K.·Wirnowski, G.·Chitkara, S.·Ambrose, C.·Steinmetz, N.·Sridharan, A.·Sahagun, D.·Banfield, J.·Doudna, J.·Jacobsen, S. E.

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Abstract

AbstractGenome 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 (TRV) 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.

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Weiss, T., Kamalu, M., Shi, H., Li, Z., Amerasekera, J., Adler, B. A., Song, M., Vohra, K., Wirnowski, G., Chitkara, S., Ambrose, C., Steinmetz, N., Sridharan, A., Sahagun, D., Banfield, J., Doudna, J., Jacobsen, S. E.. 2024-07-19. Viral delivery of an RNA-guided genome editor for transgene-free plant germline editing. https://doi.org/10.1101/2024.07.17.603964

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