生物技术通报 ›› 2023, Vol. 39 ›› Issue (2): 139-146.doi: 10.13560/j.cnki.biotech.bull.1985.2022-0616

• 研究报告 • 上一篇    下一篇

杧果Fe-S簇装配基因MiISU1的生物学功能

崔吉洁1(), 蔡文波1, 庄庆辉1, 高爱平2, 黄建峰2, 陈亚辉3, 宋志忠1,3()   

  1. 1.鲁东大学农林工程研究院 山东省高校作物高产抗逆分子模块育种重点实验室,烟台 264025
    2.中国热带农业科学院作物品种资源研究所,海口 571100
    3.南京林业大学林学院,南京 210037
  • 收稿日期:2022-05-16 出版日期:2023-02-26 发布日期:2023-03-07
  • 作者简介:崔吉洁,女,研究方向:果树分子生物学;E-mail: cjj1412669836@icloud.com
  • 基金资助:
    国家自然科学基金项目(31501743);国家重点研发计划(2019YFD1000500)

Biological Function of Gene MiISU1 for Fe-S Cluster Assembly in Mangifera indica

CUI Ji-jie1(), CAI Wen-bo1, ZHUANG Qing-hui1, GAO Ai-ping2, HUANG Jian-feng2, CHEN Ya-hui3, SONG Zhi-zhong1,3()   

  1. 1. The Engineering Research Institute of Agriculture and Forestry, Ludong University/Key Laboratory of Molecular Module-Based Breeding of High Yield and Abiotic Resistant Plants in Universities of Shandong, Yantai 264025
    2. Tropical Crops Genetic Resources Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou 571100
    3. College of Forestry, Nanjing Forestry University, Nanjing 210037
  • Received:2022-05-16 Published:2023-02-26 Online:2023-03-07

摘要:

Fe-S簇装配机制相关基因在植物生长发育过程中起重要作用,克隆参与杧果线粒体Fe-S簇装配机制的ISU1,并分析其生物学功能,为研究热带果树Fe-S簇装配的分子机制提供基因资源和理论支撑。利用同源克隆法获得杧果MiISU1,通过实时荧光定量PCR分析该基因的组织特异性表达特征及其在转录水平对不同铁素处理的响应情况,创制MiISU1超表达转基因拟南芥株系并分析其潜在的生物学功能。结果表明,从二倍体杧果‘桂热82’中克隆获得MiISU1,在幼果中的表达水平最高,其次是在成熟果实、盛开期花朵和新生叶片中,而在新生根和新生韧皮部中的表达量较低;缺铁处理显著抑制了MiISU1在一年生杧果嫁接幼苗根中的表达量,而高铁毒害显著增强了MiISU1在整株幼苗不同组织中的表达量。此外,超表达MiISU1显著促进了转基因拟南芥的生长、铁素富集水平、叶片叶绿素含量、硝酸还原酶、乌头酸酶和琥珀酸脱氢酶的酶活力,通过增强转基因植株的根系发育进而提升对缺铁胁迫的耐受能力。MiISU1在杧果铁素营养和代谢中发挥作用,其活性受铁素供应水平的调控。

关键词: 杧果, 铁代谢, Fe-S簇装配机制, ISU1, 缺铁胁迫, 转基因拟南芥

Abstract:

Iron-sulfur(Fe-S)cluster assembly genes play important roles in plant growth and development. We focused on the cloning and functional determination of MiISU1 involved in mitochondrial Fe-S cluster assembly in mango(Mangifera indica)and analyzed its biological functions, which may provide gene resources and theoretical foundation for the molecular mechanisms of Fe-S cluster assembly in tropical crops. The MiISU1 was isolated by homology cloning technology from mango. The tissue-specific expression characteristics and their responses to different Fe supplies were detected by quantitative real-time PCR. Functional verification of MiISU1 was carried out via creating over-expressed transgenic Arabidopsis seedlings. Results showed that MiISU1 was isolated from diploid mango ‘Guire 82’, whose expression was the highest in young fruits, followed by mature fruits, full-bloom flowers and new leaves, but was low in new roots and new phloem. In addition, Fe depletion significantly reduced the expression of MiISU1 in the roots of 1-year-old grafted seedlings, while high Fe toxicity significantly enhanced the expression of MiISU1 in the whole tested seedlings. Moreover, over-expression of MiISU1 in Arabidopsis significantly enhanced plant growth, accompanied with enhanced Fe accumulation, leaf total chlorophyll, nitrite reductase(NIR), aconitase(ACO)and succinate dehydrogenase(SDH)activities in transgenic lines, and improved plant resistance to Fe depletion via enhancing the root growth and development. MiISU1 plays a key role in Fe nutrition and metabolism of mango, which is regulated by external Fe status.

Key words: Mangifera indica, Fe metabolism, Fe-S cluster assembly machinery, ISU1, Fe deficiency stress, transgenic Arabidopsis