中国农业科学 ›› 2023, Vol. 56 ›› Issue (5): 821-837.doi: 10.3864/j.issn.0578-1752.2023.05.002

• 作物遗传育种·种质资源·分子遗传学 • 上一篇    下一篇

调控玉米株高和穗位高候选基因Zmdle1的定位

周文期1(), 张贺通2, 何海军1, 龚佃明2, 杨彦忠1, 刘忠祥1, 李永生1, 王晓娟1, 连晓荣1, 周玉乾1(), 邱法展2()   

  1. 1 甘肃省农业科学院作物研究所,兰州 730070
    2 华中农业大学作物遗传改良全国重点实验室,武汉 430070
  • 收稿日期:2022-10-26 接受日期:2022-12-25 出版日期:2023-03-01 发布日期:2023-03-13
  • 通信作者: 周玉乾,E-mail:yuqianzhou2008@163.com。邱法展,E-mail:qiufazhan@mail.hzau.edu.cn
  • 联系方式: 周文期,E-mail:zhouwenqi850202@163.com。
  • 基金资助:
    国家自然科学基金(32160490); 作物遗传改良全国重点实验室开放课题资助; 甘肃省重大专项(21ZD11NA005); 甘肃省重大专项(21ZD10NF003); 甘肃省农业科学院生物育种专项共同资助(2022GAAS04)

Candidate Gene Localization of ZmDLE1 Gene Regulating Plant Height and Ear Height in Maize

ZHOU WenQi1(), ZHANG HeTong2, HE HaiJun1, GONG DianMing2, YANG YanZhong1, LIU ZhongXiang1, LI YongSheng1, WANG XiaoJuan1, LIAN XiaoRong1, ZHOU YuQian1(), QIU FaZhan2()   

  1. 1 Crops Research Institute, Gansu Academy of Agricultural Sciences, Lanzhou 730070
    2 National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070
  • Received:2022-10-26 Accepted:2022-12-25 Published:2023-03-01 Online:2023-03-13

摘要:

【目的】株高是玉米株型育种的重要目标性状之一,不仅与玉米籽粒的机械化收获及抗倒伏相关,也与玉米产量密切相关。因此,挖掘玉米株高QTL/基因并解析其功能具有重要的理论和育种价值,定位一个新的玉米矮秆基因ZmDLE1,阐明其生物学功能,为加速改良玉米的株型提供重要的理论依据和基因资源。【方法】利用化学诱变剂甲基磺酸乙酯(EMS)诱变甘肃省农业科学院作物研究所自育玉米骨干自交系LY8405,M2后代分离获得一个单基因调控隐性遗传的玉米矮秆低穗位突变体,M3、M4后代能稳定遗传,命名为dwarf and low ear mutant1Zmdle1),通过与Mo17杂交构建F2分离群体,借助极端性状混池测序分析法(BSA-seq)及目标区段重组交换鉴定的方法,基于Mo17参考基因组对目标区段内的基因进行挖掘和功能注释,定位候选基因。【结果】开展了Zmdle1表型鉴定,突变体Zmdle1苗期表型与对照LY8405无显著性差异,成熟期植株株高和穗位高较LY8405分别降低87.2和55.4 cm,为35.0%和62.9%,差异极显著。细胞形态学观察表明,穗下节间数减少及节间细胞长度缩短是导致Zmdle1的株高和穗位高显著降低的主要原因。利用F2﹕3遗传群体,进行突变基因的遗传分析,后代野生型和突变体植株分离比例符合3﹕1(χ2=2.854),说明突变基因为细胞核遗传的单隐性基因。因此,根据BSA-seq结果,将候选基因ZmDLE1初步定位在玉米第1染色体Bin1.09-1.10区段约15 Mb区间内,进一步利用Mo17和Zmdle1重测序结果开发多态性分子标记,通过图位克隆手段精细定位目标基因,最终将候选基因定位到约600 kb大小区间,该区间内有16个候选基因。比对重测序数据,发现Zm00001d033231在第2 062位置碱基G变成A,导致氨基酸由甘氨酸变成丝氨酸,且转录水平表达比LY8405极显著降低,Zm00001d033234第223位置碱基由T变成C,导致第75位氨基酸由丝氨酸变成脯氨酸,转录水平无显著差异,通过对该候选区段群体关联分析及功能注释发现,Zm00001d033231Zm00001d033234均与玉米生长发育相关。【结论】定位到第1染色体末端Bin1.09区段候选基因ZmDLE1,有效调控玉米株高和穗位高,精细定位缩小目标区段至600 kb,区间内Zm00001d033231与株高显著关联。

关键词: 玉米, 株高, 穗位高, BSA-seq, 基因定位, 关联分析

Abstract:

【Objective】 Plant height is one of the important target traits in maize plant type breeding, which is closely related not only to mechanized grain harvesting and lodging resistance, but also to maize yield. Therefore, it is of great theoretical and breeding value to isolate QTL/gene of maize plant height and analyze its function. This study aims to locate a novel maize dwarf gene ZmDLE1, clarify its biological function, and provide important theoretical basis and gene resources for accelerating the improvement of maize plant type. 【Method】 A single recessive mutant was derived in maize inbred line LY8405, from Crop Research Institute of Gansu Academy of Agricultural Sciences, by chemical mutagenic agent Ethyl Methyl Sulfonate (EMS). A maize dwarf and low ear mutant was isolated from the M2 progeny, and the M3 and M4 progeny could stably inherit, which was named dwarf and low ear mutant1 (Zmdle1). The F2 population was constructed by hybridization with Mo17 and was identified by bulked segregate analysis-sequencing (BSA-seq) and target segment recombination exchange. Based on the Mo17 reference genome, the genes in the target region were obtained and functionally annotated to locate candidate genes.【Result】Phenotypic identification of Zmdle1 was carried out, and the phenotype of Zmdle1 at seedling stage was not significantly different from that of the control LY8405. The plant height and ear height of Zmdle1 at mature stage were reduced by 87.2 cm and 55.4 cm, respectively, accounting for about 35.0% and 62.9%, difference is extremely significant. Morphological observation showed that the decrease of internode number and the shortening of internode cell length were the main reasons for the significant decrease of plant height and ear height of Zmdle1. The genetic analysis of the mutant gene was conducted by using the F2:3 genetic populations. The Zmdle1 mutant is inherited in a 3﹕1 (χ2=2.854) ratio and is a single recessive gene. Therefore, according to the results of BSA-seq, the candidate gene ZmDLE1 was initially located in the 15 Mb region of Bin1.09-1.10 on chromosome 1 of maize. The polymorphism molecular markers were further developed using the re-sequencing results of Mo17 and Zmdle1, and the target gene was accurately cloned by map-based cloning. Finally, the candidate genes were mapped to the size range of 600 kb, and there were 16 candidate genes in this range. By comparing the re-sequencing data, it was found that Zm00001d033231 gene changed into A at the 2062 position G, which resulted in amino acid changing from glycine to serine, and the transcription level expression was significantly reduced compared with LY8405. Zm00001d033234 changed from T to C at the 223rd position leading to the 75th amino acid changed from serine to proline, and there was no significant difference in transcription level. Through association analysis of natural populations and the predicted genes for functional annotation, it was found that Zm00001d033231 and Zm00001d033234 were related to the growth and development of maize. 【Conclusion】 The candidate gene ZmDLE1 in the Bin1.09 region at the end of chromosome 1, was identified to effectively regulate maize plant height and ear height, and the target region was reduced to 600 kb by fine localization. Association analysis showed that Zm00001d033231 was genetic locus significantly associated with plant height within the target region.

Key words: maize, plant height, ear height, BSA-seq, fine mapping, association analysis