Engineering high amylose and resistant starch in maize by CRISPR/Cas9-mediated editing of starch branching enzymes

作     者：Mingzheng Ma Shanqiu Sun Jinjie Zhu Xiantao Qi Gaoke Li Jianguang Hu Chuanxiao Xie Changlin Liu Mingzheng Ma;Shanqiu Sun;Jinjie Zhu;Xiantao Qi;Gaoke Li;Jianguang Hu;Chuanxiao Xie;Changlin Liu

作者机构：State Key Laboratory of Crop Gene Resources and BreedingInstitute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China Hainan Yazhou Bay Seed LabSanya 572024HainanChina Anhui Agricultural UniversityHefei 230036AnhuiChina Crops Research InstituteGuangdong Academy of Agricultural SciencesGuangzhou 510640GuangdongChina 

出 版 物：《The Crop Journal》 (作物学报（英文版）)

年 卷 期：2024年第12卷第4期

页      面：1252-1258页

核心收录：

学科分类：0710[理学-生物学] 09[农学] 0901[农学-作物学] 

基　　金：supported by the National Key Research and Development Program of China(2023YFD1202901) the China Agriculture Research System of MOF and MARA(CARS-02-06) the Key Area Research and Development Program of Guangdong Province(2018B020202008) 

主　　题：Maize Gene editing Starch branching enzyme I Starch branching enzyme IIb 

摘      要：To improve the amylose content(AC)and resistant starch content(RSC)of maize kernel starch,we employed the CRISPR/Cas9 system to create mutants of starch branching enzyme I(SBEI)and starch branching enzyme IIb(SBEIIb).A frameshift mutation in SBEI(E1,a nucleotide insertion in exon 6)led to plants with higher RSC(1.07%),lower hundred-kernel weight(HKW,24.71±0.14 g),and lower plant height(PH,218.50±9.42 cm)compared to the wild type(WT).Like the WT,E1 kernel starch had irregular,polygonal shapes with sharp edges.A frameshift mutation in SBEIIb(E2,a four-nucleotide deletion in exon 8)led to higher AC(53.48%)and higher RSC(26.93%)than that for the WT.E2 kernel starch was significantly different from the WT regarding granule morphology,chain length distribution pattern,X-ray diffraction pattern,and thermal characteristics;the starch granules were more irregular in shape and comprised typical B-type *** SBEI and SBEIIb(E12)had a synergistic effect on RSC,HKW,PH,starch properties,and starch biosynthesis-associated gene ***,SS1,SSIIa,SSIIIa,and SSIIIb were upregulated in E12 endosperm compared to WT *** study lays the foundation for rapidly improving the starch properties of elite maize lines.