应用CRISPR/Cas9技术创制低直链淀粉含量水稻种质  

Creating Novel Rice Germplasms with Low Amylose Content by Editing Upstream Sequence of Wx Gene Coding Region via CRISPR/Cas9 Technology

作　　者：毛兴学[1] 郑晓钰 孙炳蕊[1] 李晨[1] 陈文丰[1] 潘大建[1] 柳武革[1] 范芝兰[1] 王丰[1] MAO Xing-xue;ZHENG Xiao-yu;SUN Bing-rui;LI Chen;CHEN Wen-feng;PAN Da-jian;LIU Wu-ge;FAN Zhi-lan;WANG Feng(Rice Research Institute,Guangdong Academy of Agricultural Sciences/Guangdong Key Laboratory of New Technology in Rice Breeding/Guangdong Rice Engineering Laboratory,Guangzhou 510640)

机构地区：[1]广东省农业科学院水稻研究所/广东省水稻育种新技术重点实验室/广东省水稻工程实验室,广州510640

出　　处：《植物遗传资源学报》2022年第2期583-591,共9页Journal of Plant Genetic Resources

基　　金：广东省发展和改革委、农业农村厅投资项目[2021]272号;广东农业科学院农业优势产业学科团队建设项目(202101TD);广东省重点领域研发计划项目(2020B0202090003);广东省自然科学基金(2019A1515011208、2021A1515011226);广东省重点实验室运行费(2020B1212060047)。

摘　　要：Wx基因直接控制水稻胚乳直链淀粉的合成,进而影响胶稠度等多个品质指标,是控制稻米食味的主效基因。适当降低稻米的直链淀粉含量可改善稻米品质。吉丰B是籼型优质杂交稻保持系,直链淀粉含量偏高,影响组配后代的食味品质。本研究以吉丰B为试验材料,对Wx基因编码区上游序列进行编辑,以期获得Wx基因表达下调,直链淀粉含量降低的水稻种质。以农杆菌为介导进行转基因,获得9个转基因株系,从后代中筛到2个大片段缺失的变异株系L8和L9。它们的Wx基因表达大幅下调,直链淀粉含量极显著降低,胶稠度和食味品质也有所改善。L8和L9糙米外观有很大差异,L8与糯米相近,L9与粘米类似。综上所述,本研究利用CRISPR/Cas9技术编辑Wx基因编码区上游序列,获得两份低直链淀粉含量水稻种质,该结果为稻米品质改良研究提供了参考。Wx gene directly controls the synthesis of amylose in rice endosperm,and thus affects many cooking quality traits such as gel consistency,which is the major gene controlling the eating quality of rice. It can significantly improve the rice eating quality by moderately reducing amylose content(AC). Jifeng B(JB)is a maintainer line of indica hybrid rice with high AC,which reduces the eating quality of the progeny. CRISPR/Cas9 technology has been applied more and more in rice molecular breeding. In this study,four target sites were selected from the upstream sequence of coding region of Wx gene,and the editing vector was constructed and introduced into JB by Agrobacterium tumefaciens. A total of 9 transgenic lines,L1-L9,were obtained. Among them,L8 and L9 had a large fragment deletion mutation,in which the expression of Wx gene and AC were downregulated. The gel consistency and eating quality were also improved. There is a great difference in the appearance of brown rice between L8 and L9. L8 is similar to glutinous rice and L9 is similar to sticky rice. To sum up,we used CRISPR/Cas9 technology to edit the upstream untranslated region of Wx gene in order to reduce the AC in rice,and achieved success. These results provide a reference for the study of rice quality improvement.

关 键 词：水稻(Oryza sativa L.) WX基因 直链淀粉含量 CRISPR/Cas9 

分 类 号：S511[农业科学—作物学]