Precise base editing of non-allelic acetolactate synthase genes confers sulfonylurea herbicide resistance in maize
Precise base editing of non-allelic acetolactate synthase genes confers sulfonylurea herbicide resistance in maize
复制标题
非等位基因乙酰乳酸合酶基因的精确碱基编辑赋予玉米磺酰脲类除草剂抗性
DOI：
10.1016/j.cj.2019.10.001
复制
发表时间：
2020-06-01
期刊：
影响因子：
6.6
通讯作者：
Xie, Chuanxiao
中科院分区：
文献类型：
--
作者：
Li, Yanmin;Zhu, Jinjie;Xie, Chuanxiao
单核苷酸多态性有助于玉米表型多样性。基于随机突变的传统方法效率低下，限制了点突变的创建和功能注释。一个有效的工具，用于产生有针对性的单碱基突变的功能基因组学和精确的遗传改良是可取的。本研究的目的是测试两个非等位乙酰乳酸合酶（ALS）的靶向C-to-T碱基编辑在产生磺酰脲除草剂抗性突变体中的效率。使用与尿嘧啶DNA糖基化酶抑制剂（UGI）融合的CRISPR/Cas9切口酶-胞苷脱氨酶来实现ZmALSl和ZmALS 2中胞嘧啶向胸腺嘧啶的靶向转化。原生质体和恢复的突变体植物都显示出胞嘧啶碱基编辑器的活性，体内效率高达13.8%。携带纯合ZmALS 1突变或ZmALS 1和ZmALS 2双突变的无转基因编辑的植物在高达氯磺隆（一种广泛用于农业的磺酰脲除草剂）推荐限度的15倍的剂量下测试其抗性。C-to-T的靶向碱基编辑本身和在所产生的突变体中验证的表型证明了碱基编辑在精确玉米育种中的力量。(C)2019中国农业科学院作物科学研究所中国作物学会Elsevier B. V.代表KeAiCommunications Co.制作和主办，公司
Single-nucleotide polymorphisms contribute to phenotypic diversity in maize. Creation and functional annotation of point mutations has been limited by the low efficiency of conventional methods based on random mutation. An efficient tool for generating targeted single-base mutations is desirable for both functional genomics and precise genetic improvement. The objective of this study was to test the efficiency of targeted C-to-T base editing of two non-allelic acetolactate synthase (ALS) in generating sulfonylurea herbicide-resistant mutants. A CRISPR/Cas9 nickase-cytidine deaminase fused with uracil DNA glycosylase inhibitor (UGI) was employed to achieve targeted conversion of cytosine to thymine in ZmALS1 and ZmALS2. Both protoplasts and recovered mutant plants showed the activity of the cytosine base editor, with an in vivo efficiency of up to 13.8%. Transgene-free edited plants harboring a homozygous ZmALS1 mutation or a ZmALS1 and ZmALS2 double mutation were tested for their resistance at a dose of up to 15-fold the recommended limit of chlorsulfuron, a sulfonylurea herbicide widely used in agriculture. Targeted base editing of C-to-T per se and a phenotype verified in the generated mutants demonstrates the power of base editing in precise maize breeding. (C) 2019 Crop Science Society of China and Institute of Crop Science, CAAS. Production and hosting by Elsevier B.V. on behalf of KeAiCommunications Co., Ltd.