背景回顾：Promoter editing represents an innovative approach to introduce quantitative trait variation (QTV) in crops. 

提出问题：However, an efficient promoter editing system for QTV needs to be established. 

主要发现：Here we develop a CRISPR–Cas12a promoter editing (CAPE) system that combines a promoter key-region estimating model and an efficient CRISPR–Cas12a-based multiplexed or singular editing system. 

结果1-GBSS1和GS3：CAPE is benchmarked in rice to produce QTV continuums for grain starch content and size by targeting OsGBSS1 and OsGS3, respectively. 

结果2-D18：We then apply CAPE for promoter editing of OsD18, a gene encoding GA3ox in the gibberellin biosynthesis pathway. The resulting lines carry a QTV continuum of semidwarfismwithout significantly compromising grain measures. Field trials demonstrated that the OsD18 promoter editing lines have the same yield performance and antilodging phenotype as the Green Revolution OsSD1 mutants in different genetic backgrounds. Hence, promoter editing of OsD18 generates a quantitative Green Revolution trait. 

结论：Together, we demonstrate a CAPE-based promoter editing and tuning pipeline for efficient production of useful QTV continuum in crops.

启动子编辑是往作物中引入数量性状变异的一个创新途径。但是，用于数量性状变异的高效启动子编辑系统仍然有待建立。本文中，作者开发了一套基于CRISPR–Cas12a的启动子编辑系统CAPE，该系统结合了一个启动子关键区域的预测模型以及一个基于CRISPR–Cas12a的高效单/多基因编辑系统。作者在水稻中成功利用CAPE系统分别靶向OsGBSS1和OsGS3基因，各创制了一套籽粒淀粉含量和籽粒大小的连续数量性状变异集合。接着，作者利用CAPE系统靶向一个编码赤霉素生物合成途径中的关键基因OsD18的启动子，获得了一套不影响籽粒产量的半矮杆连续变异集合。田间试验显示，在不同遗传背景下，OsD18启动子编辑株系与绿色革命OsSD1突变体具有同样的产量和抗倒伏表型。因此，通过对OsD18基因的启动子编辑，产生了一个绿色革命数量性状。综上，作者构建了一个CAPE启动子编辑系统，为高效作物创制数量性状变异提供技术平台。

** 张 勇 **