Expanding the target range of base editing in plants without loss of efficiency by blocking RNA-silencing.

Abstract

Bacterial-derived CRISPR/Cas systems are versatile platforms to engineer site-specific gene editing tools. Compared to the canonical Cas9-mediated DNA cleavage systems, which induce a high-proportion of frame-shift mutations, the recently developed base editing (BE) tools allow more precise and predictable base substitutions within a CRISPR/Cas9-defined editing window. Initially, such tools made use of engineered cytosine deaminases or evolved adenine deaminases to catalyze base deamination when fused to a Cas9 nickase (nCas9) (Rees and Liu, 2018).