一份新的玉米永久性失绿突变体chs10的鉴定及基因克隆  

Identification and Gene Cloning of A New Maize Permanent chlorosis Mutant chs10

作　　者：侯雨微 岳毓菁 李川 苏帅 易洪杨 曹墨菊[1] HOU Yuwei;YUE Yujing;LI Chuan;SU Shuai;YI Hongyang;CAO Moju(Maize Research Institute,Sichuan Agricultural University/Key Laboratory of Biology and Genetic Improvement of Maize in Southwest Region,Chengdu 611130,China)

机构地区：[1]四川农业大学玉米研究所/农业农村部西南玉米生物学与遗传育种重点实验室,成都611130

出　　处：《四川农业大学学报》2024年第1期46-56,102,共12页Journal of Sichuan Agricultural University

基　　金：“十四五”国家重点研发计划项目(2022YFD1200704-3);四川省科技计划重点研发项目(2021YFYZ0011);国防科工局核能开发科研项目“核辐射作物品种改良与害虫防控”。

摘　　要：【目的】利用60Co-γ射线处理自交系齐319获得了一份新的玉米叶色突变体,对该突变体进行遗传分析、基因定位与克隆,并对候选基因的功能进行初步分析。【方法】以该突变体为亲本,构建遗传分析群体和基因定位群体;通过图位克隆技术获得关键候选基因;利用生物信息学方法分析关键候选基因的结构和进化关系;通过qRT-PCR技术检测候选基因在不同组织中的表达差异;同时运用烟草瞬时表达技术对候选基因进行亚细胞定位表达分析。【结果】鉴定了一份玉米永久性失绿突变体chs10(Permanent chlorosis 10),chs10自V2时期开始,叶片从幼苗基部到顶部逐渐由绿转黄,后期的生长发育过程中不再复绿,并且,整个植株包括叶鞘、叶环、茎秆、苞叶和雄穗也均为黄色。该突变体受一对隐性核基因控制,可稳定遗传,植株生长发育正常,可正常授粉结实。突变基因被定位于玉米第10染色体长臂标记SNP-2和SNP-3之间约0.17 Mb范围内,确定了关键候选基因Zm00001d025860,qRT-PCR结果显示Zm00001d025860在玉米根、茎、叶和叶鞘中均有表达,但在叶片中高表达,亚细胞定位结果显示目标蛋白被定位在细胞膜和叶绿体中。利用STRING预测发现Zm00001d025860与卟啉结合蛋白GUN4基因互作,GUN4与叶绿素合成中的镁离子螯合酶(MgCh)具有反馈调节作用。【结论】Zm00001d025860基因的突变导致突变体chs10叶色的改变,并且Zm00001d025860可能通过参与叶绿素合成途径来调控叶色变化。突变体chs10的发现一方面丰富了玉米叶色突变体研究的基因资源,同时为解析镁离子螯合酶在叶绿素合成途径中的作用机理奠定了材料基础。【Objective】This study is aiming at genetically analyzing,gene mapping,and preliminarily analysze the function of the candidate genes of a new maize leaf color mutant obtained by treating the inbred line Qi 319 with 60Co-γrays.【Method】The mutant was used as the parent to construct a genetic analysis population and a gene mapping population;the key candidate genes were obtained by map cloning;the structure and evolutionary relationship of the key candidate genes were analyzed by bioinformatics;the expression of the candidate genes in different tissues was detected by qRT-PCR;and the subcellular localization of the candidate genes was analyzed by using the tobacco transient expression technology.【Result】A maize permanent chlorosis mutant chs10(Permanent chlorosis 10)was identified.Starting from the V2 stage,the leaves of chs10 gradually turn from green to yellow from the base to the top of the seedling,During the later growth and development process,they no longer return to green,and the whole plant,including leaf sheaths,leaf rings,stems,bracts,and tassel,was also yellow.This mutation is controlled by a pair of recessive nuclear genes,and can be stably inherited.The plant growth and development are normal,and it can be pollinated and fruited normally.The mutated gene is located within the range of approximately 0.17 Mb between the long arm markers SNP-2 and SNP-3 on maize chromosome 10,revealing Zm00001d025860 as the key candidate gene.qRT-PCR results showed that Zm00001d025860 was expressed in the maize roots,stems,leaves,and leaf sheaths,but was highly expressed in the leaves.Subcellular localization results showed that the target protein was localized in the cell membrane and chloroplasts.Using STRING prediction,Zm00001d025860 was found to interact with the porphyrin-binding protein GUN4,and GUN4 has a feedback regulation with magnesium ion chelatase(MgCh)in chlorophyll synthesis.【Conclusion】Mutations in the Zm00001d025860 gene lead to changes in leaf color of mutant chs10,and Zm00001d025860 may

关 键 词：玉米 遗传分析 叶色突变体 chs10 图位克隆 

分 类 号：S513[农业科学—作物学]