Efficient transgene-free multiplexed genome editing via viral delivery of an engineered TnpB.

Weiss, T.; Kamalu, M.; Shi, H.; Wirnowski, G.; Ingelsson, A.; Amerasekera, J.; Vohra, K.; Trinidad, M. I.; Li, Z.; Freitas, E.; Steinmetz, N.; Ambrose, C.; Chen, K.; Doudna, J. A.; Jacobsen, S. E.

doi:10.64898/2026.01.23.700382

bioRxiv · 10.64898/2026.01.23.700382

Efficient transgene-free multiplexed genome editing via viral delivery of an engineered TnpB.

Weiss, T.·Kamalu, M.·Shi, H.·Wirnowski, G.·Ingelsson, A.·Amerasekera, J.·Vohra, K.·Trinidad, M. I.·Li, Z.·Freitas, E.·Steinmetz, N.·Ambrose, C.·Chen, K.·Doudna, J. A.·Jacobsen, S. E.

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Abstract

Virus-induced genome editing (VIGE) using compact RNA-guided endonucleases is a transformational new approach in plant biotechnology, enabling tissue-culture-independent and transgene-free genome editing (Hu et al. 2025; Liu et al. 2025; Weiss et al. 2025). We recently established a VIGE approach for heritable editing at single loci in Arabidopsis by delivering the compact genome editor ISYmu1 TnpB (Ymu1) and its guide RNA (gRNA) via Tobacco Rattle Virus (TRV) (Weiss et al. 2025). Here, we greatly improved this approach by devising a multiple gRNA expression system and by utilizing an engineered high-activity Ymu1 variant (Ymu1-WFR) (Zhou et al. 2026) to develop an efficient multiplexed genome editing platform.

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Weiss, T., Kamalu, M., Shi, H., Wirnowski, G., Ingelsson, A., Amerasekera, J., Vohra, K., Trinidad, M. I., Li, Z., Freitas, E., Steinmetz, N., Ambrose, C., Chen, K., Doudna, J. A., Jacobsen, S. E.. 2026-01-23. Efficient transgene-free multiplexed genome editing via viral delivery of an engineered TnpB.. https://doi.org/10.64898/2026.01.23.700382

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