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bioRxiv · 10.1101/2021.01.08.425920

Strong and tunable anti-CRISPR/Cas9 activity of AcrIIA4 in plants

Calvache, C.·Vazquez-Vilar, M.·Selma, S.·Uranga, M.·Daros, J. A.·Orzaez, D.
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Abstract

This study describes the strong anti-CRISPR activity of the bacterial AcrIIA4 protein in Nicotiana benthamiana, a model plant used as molecular farming platform. The results demonstrate that AcrIIA4 abolishes site-directed mutagenesis in leaves when transiently co-expressed with CRISPR/Cas9. We also show that AcrIIA4 represses CRISPR/dCas9-based transcriptional activation (CRISPRa) of both reporter and endogenous genes in a highly efficient, dose-dependent manner. Furthermore, the fusion of an auxin degron to AcrIIA4 results in auxin-regulated activation of a downstream reporter gene. The strong anti-Cas9 activity of AcrIIA4 reported here opens new possibilities for customized control of gene editing and gene expression in plants.

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Calvache, C., Vazquez-Vilar, M., Selma, S., Uranga, M., Daros, J. A., Orzaez, D.. 2021-01-08. Strong and tunable anti-CRISPR/Cas9 activity of AcrIIA4 in plants. https://doi.org/10.1101/2021.01.08.425920

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