生物技术通报 ›› 2024, Vol. 40 ›› Issue (1): 194-206.doi: 10.13560/j.cnki.biotech.bull.1985.2023-0672

• 研究报告 • 上一篇    下一篇

小麦镉胁迫响应基因TaMYB1的功能分析

张怡1,2(), 张心如1,2, 张金珂1,2, 胡利宗1,2, 上官欣欣1,2, 郑晓红1,2, 胡娟娟1,2, 张聪聪1,2, 穆桂清1,2, 李成伟3()   

  1. 1.周口师范学院植物遗传与分子育种重点实验室,周口 466001
    2.河南省作物育种与生物反应器重点实验室,周口 466001
    3.河南工业大学粮油食品学院,郑州 450000
  • 收稿日期:2023-07-14 出版日期:2024-01-26 发布日期:2024-02-06
  • 通讯作者: 李成伟,男,教授,研究方向:植物与微生物互作;E-mail: lichengweihist@163.com
  • 作者简介:张怡,女,博士,副教授,研究方向:植物与微生物互作;E-mail: yizhang0401@sina.com
  • 基金资助:
    国家自然科学基金项目(32102487);国家自然科学基金项目(32001921);河南省科技攻关项目(232102111094);河南省高校大学生创新创业训练计划(202210478011)

Functional Analysis of TaMYB1 Gene in Wheat Under Cadmium Stress

ZHANG Yi1,2(), ZHANG Xin-ru1,2, ZHANG Jin-ke1,2, HU Li-zong1,2, SHANGGUAN Xin-xin1,2, ZHENG Xiao-hong1,2, HU Juan-juan1,2, ZHANG Cong-cong1,2, MU Gui-qing1,2, LI Cheng-wei3()   

  1. 1. Key Laboratory of Plant Genetics and Molecular Breeding, Zhoukou Normal University, Zhoukou 466001
    2. Henan Key Laboratory of Crop Molecular Breeding & Bioreactor, Zhoukou 466001
    3. College of Food Science and Engineering, Henan University of Technology, Zhengzhou 450000
  • Received:2023-07-14 Published:2024-01-26 Online:2024-02-06

摘要:

【目的】MYB家族成员在植物生长发育、生物胁迫和非生物胁迫等方面发挥重要调控作用,然而,小麦MYB转录因子在重金属镉(Cd)胁迫中的生物学功能研究较少。挖掘小麦Cd胁迫应答相关基因,阐明其在Cd胁迫中的生物学功能,为耐/低Cd小麦品种的选育奠定基础。【方法】构建Cd胁迫小麦根系酵母cDNA文库,筛选获得Cd胁迫应答基因,利用荧光定量PCR技术检测Cd胁迫条件下小麦不同组织中Cd胁迫应答基因的相对表达量;利用病毒诱导的基因沉默对该基因进行功能验证,检测对照和沉默植株的Cd含量、叶绿素含量、丙二醛(MDA)含量、超氧化物歧化酶(SOD)和过氧化物酶(POD)活力等生理生化指标。此外,对Cd胁迫应答基因及其在小麦和其他物种中的同源基因进行生物信息学分析(系统进化关系、序列特征和表达谱)。【结果】Cd胁迫主要抑制小麦根系发育,在添加0.002 mol/L Cd的酵母培养基上筛选Cd胁迫小麦根系酵母cDNA文库获得18个耐Cd转化子,其中5个转化子编码TaMYB1蛋白,转化TaMYB1酵母菌株在高Cd培养基中生长良好,而对照则明显受到抑制。RT-qPCR结果表明,TaMYB1在小麦幼苗中响应Cd胁迫。与对照相比,TaMYB1沉默植株中TaMYB1表达量明显下降,且根系和叶片Cd含量显著低于对照植株,叶绿素含量、SOD、POD活性高于对照植株,MDA含量则低于对照植株。同时,生物信息学分析发现,TaMYB1属于1R-MYB家族成员,具有高度保守的MYB和CC结构域,其包含7个外显子和6个内含子,在拔节期中期的花序和成熟期的花序表达最高,在灌浆前期种子和灌浆中后期种子中表达量最低。【结论】TaMYB1在小麦响应Cd胁迫应答中发挥重要作用。

关键词: 小麦, 非生物胁迫, 镉, 酵母, 病毒诱导的基因沉默

Abstract:

【Objective】Members of the MYB family play key roles in diverse biological processes including regulation of plant growth and development, biotic and abiotic stress. However, there were few researches specifically focusing on the function of MYB transcription factors in the response to cadmium(Cd)stress in Triticum aestivum. Therefore, identifying Cd-responsive genes and illustrating their biological function may lay a foundation for wheat Cd-resistant or low-Cd breeding. 【Method】Firstly, the yeast cDNA library of wheat roots under Cd stress was constructed, and then the Cd-resistant gene was screened. Then, the expression patterns of Cd-resistant gene in different tissues under Cd stress were examined by quantitative real-time PCR(RT-qPCR). The function of the gene was verified by virus-induced gene silencing, and physiological and biochemical indicators such as the Cd content, chlorophyll content, malondialdehyde(MDA)content, superoxide dismutase(SOD)and peroxidase(POD)activities of the control and gene-silenced plants were detected. Finally, the candidate Cd-resistant gene and its homologous genes in other plants were analyzed by evolutionary relationship, gene structure and expression profile in detail. 【Result】The results indicated that root development of wheat was mainly inhibited under Cd stress. Total 18 positive transformants were screened by cDNA library on a tolerance of 0.002 mol/L Cd, and five transformants encoded TaMYB1 protein, which grew well while the control yeast strains restrained in high Cd medium. Results of RT-qPCR indicated that TaMYB1 responded to Cd stress in the wheat. Compared to the control, TaMYB1 expression in TaMYB1-silencing wheat significantly decreased and the concentration of Cd in the roots and leaves as well MDA content were remarkably lower than that in the control plants, while the contents of chlorophyll and the activities of SOD and POD increased apparently in TaMYB1-silencing plants. Meanwhile, bioinformatics analysis found that TaMYB1 belonged to the 1R-MYB family with highly conserved MYB and CC domains, containing seven exons and six introns. TaMYB1 expressed the highest in the inflorescences of two nodes or internodes visible stage and maximum stem length reached stage, while the lowest in in pre-filling seeds and mid- and late-filling seeds. 【Conclusion】TaMYB1 plays a important role in wheat response to Cd stress.

Key words: Triticum aestivum, abiotic stress, cadmium, yeast, virus-induced gene silencing