小麦NF-YB型转录基因TaNF-YB4介导植株抵御干旱功能研究  

Characteristics of wheat transcription factor gene TaNF-YB4 in mediating drought tolerance of plants

作　　者：杜萍萍 赵颖佳 史桂清 肖凯[1] DU Pingping;ZHAO Yingjia;SHI guiqing;XIAO Kai(College of Agronomy,Hebei Agricultural University,Baoding 071001,China)

机构地区：[1]河北农业大学农学院,河北保定071001

出　　处：《河北农业大学学报》2021年第2期1-8,共8页Journal of Hebei Agricultural University

基　　金：国家自然科学基金项目(31872869);国家重点研发项目粮丰专项(2017YFD0300902)。

摘　　要：核因子Y(NF-Y)转录因子通过调控下游基因转录,在介导植株抵御非生物逆境中发挥重要作用。作者以前期鉴定的1个归属于NF-YB家族基因TaNF-YB4为基础,对该基因分子特征、应答干旱胁迫表达模式及遗传转化对植株抵御干旱逆境能力的影响进行了研究。结果表明:TaNF-YB4编码蛋白含有植物种属NF-YB家族保守的H4超家族保守域和核定位基序。该基因转录本在根叶中呈典型的干旱诱导表达模式,表现为随着干旱胁迫进程表达增高趋势。与野生型对照相比,正反义表达TaNF-YB4株系干旱处理下植株长势发生明显改变,表现为正义系(Sen 1)植株长势增强,干质量和叶面积增加;而反义系(Anti 2)植株长势变差,干质量和叶面积降低。对正反义株系气孔关闭特征观测发现,Sen 1和Anti 2干旱下气孔关闭分别较对照加快和减慢。此外,干旱处理下,与对照相比,正义系光合能力、可溶蛋白和可溶性糖含量和细胞活性氧稳态相关参数均明显改善。组织特异性分析表明,TaNF-YB4基因调控干旱胁迫下植株抗旱相关生理过程和生化代谢途径,改善植株糖氮积累、光合碳同化和细胞活性氧稳态,在调控植株抵御干旱逆境过程中发挥着重要生物学功能。The transcription factors categorized into nuclear factor(NF-Y) type play critical roles in mediating plant tolerance to various abiotic stresses through regulating downstream genes at transcriptional level.In this study, based on the previous research of TaNF-YB4 which was characterized as a gene of the NF-YB family, we studied its molecular property, expression patterns upon drought stress, and the effects of genetic transformation on plant drought adaptation. Results indicated that TaNF-YB4 encodes a protein sharing conserved H4 superfamily domain together with a nuclear localization motif. Expression analysis revealed that TaNF-YB4 display induced transcripts in both roots and leaves upon drought stressor, with a pattern of elevation over drought stress progression. Compared with the control(wild type), the tobacco line with TaNF-YB4 overexpression(Sen 1) showed enlarged phenotype, increased plant biomass, and enhanced leaf area under drought treatment. In contrast, the line with knockdown expression of TaNF-YB4(Anti 2) exhibited alleviated growth feature, decreased plant biomass, and reduced leaf area once challenged with drought. The stomata closure rates in Sen 1 were shown to be promoted whereas those in Anti 2 to be delayed along with the drought progression. In addition, under drought treatment, the line with TaNFYB4 overexpression showed improved photosynthetic function, contents of soluble protein and soluble sugar, and the reactive oxygen species(ROS) homestasis-associated parameters. Our investigation suggestes that TaNF-YB4 plays essential roles in mediating plant drought adaptation due to its regulation for drought-related physiological processes and biochemical pathways, which improves carbon and nitrogen accumulation, photosynthetic assimilation, and cellular ROS homeostasis of plants challenged by drought stress.

关 键 词：小麦 NF-YB转录因子 干旱胁迫 基因表达 生理参数 

分 类 号：S512[农业科学—作物学]