Expanded base editing in rice and wheat using a Cas9-adenosine deaminase fusion
Chao Li(University of Chinese Academy of Sciences), Yuan Zong(University of Chinese Academy of Sciences), Yanpeng Wang(Institute of Genetics and Developmental Biology), Shuai Jin(University of Chinese Academy of Sciences), Dingbo Zhang(Chinese Academy of Sciences), Qianna Song(Chinese Academy of Sciences), Rui Zhang(Institute of Genetics and Developmental Biology), Caixia Gao(Chinese Academy of Sciences)
Cited by 495Open Access
Abstract
Nucleotide base editors in plants have been limited to conversion of cytosine to thymine. Here, we describe a new plant adenine base editor based on an evolved tRNA adenosine deaminase fused to the nickase CRISPR/Cas9, enabling A•T to G•C conversion at frequencies up to 7.5% in protoplasts and 59.1% in regenerated rice and wheat plants. An endogenous gene is also successfully modified through introducing a gain-of-function point mutation to directly produce an herbicide-tolerant rice plant. With this new adenine base editing system, it is now possible to precisely edit all base pairs, thus expanding the toolset for precise editing in plants.