| 侯昌林，杨泽亚，韩 燚，苟筱颖，李 明，曹高燚，丁 博，谢晓东，陈小强.大麦HvERECTA基因异源表达调控拟南芥气孔发育及其抗旱分子机制研究[J].麦类作物学报,2026,(8):1014 |
| 大麦HvERECTA基因异源表达调控拟南芥气孔发育及其抗旱分子机制研究 |
| Molecular Mechanism of the Barley HvERECTA Gene in Regulating Stomatal Development and Drought Resistance through Heterologous Expression in Arabidopsis |
| |
| DOI： |
| 中文关键词: 大麦 HvERECTA基因 气孔发育 气孔密度 气孔开度 干旱胁迫 |
| 英文关键词:Hordeum vulgare HvERECTA gene Stomatal development Stomatal density Stomatal aperture Drought stress |
| 基金项目:国家农业科技重大项目（DK077701）;天津市大学生创新训练计划项目（202510061232） |
|
| 摘要点击次数: 164 |
| 全文下载次数: 52 |
| 中文摘要: |
| ERECTA受体样激酶家族在植物气孔发育及非生物胁迫响应中具有重要作用。为明确大麦HvERECTA基因在气孔发育及干旱胁迫响应中的调控机制,挖掘大麦抗旱分子育种新靶点，克隆获得大麦HvERECTA基因并进行生物信息学分析，构建异源过表达载体转化拟南芥，系统测定转基因株系的气孔表型、关键基因表达水平及干旱胁迫下的生理指标。结果表明，HvERECTA基因编码区全长2 934 bp，编码977 个氨基酸，编码蛋白定位于质膜且含典型丝氨酸/苏氨酸蛋白激酶结构域，在禾本科植物中高度保守；该基因的启动子区域富含ABRE、MBS等逆境胁迫及激素响应元件。转基因拟南芥气孔密度显著降低，气孔发育关键转录因子SPCH、MUTE、FAMA的编码基因表达量下调幅度均超50%，MAPK通路核心基因YODA表达上调50%~80%；干旱胁迫下，转基因拟南芥株系超氧化物歧化酶（SOD）、过氧化物酶（POD）、过氧化氢酶（CAT）活性较对照提升25%~40%，丙二醛含量下降约30%，失水速率降低20%，胁迫响应基因AtKIN2、AtABF3、AtRD22表达量均显著上调。综上所述，大麦HvERECTA基因通过调控MAPK信号通路降低气孔密度、增强植株抗氧化能力，从而提升抗旱性，为大麦抗旱分子育种提供了重要的功能基因资源。 |
| 英文摘要: |
| The ERECTA family of receptor like kinases(RLKs) plays a crucial regulatory role in plant stomatal development and responses to abiotic stresses. This study therefore focused on investigating the barley HvERECTA gene, aiming to clarify its regulatory roles in these biological processes and provide potential targets for barley drought resistance breeding. We first cloned the HvERECTA gene from barley and conducted comprehensive bioinformatics analyses to characterize its sequence and protein properties. Subsequently, we constructed a heterologous overexpression vector carrying the HvERECTA gene and transformed it into Arabidopsis thaliana. For the transgenic Arabidopsis lines, we systematically determined stomatal phenotypic traits, expression levels of the key related genes, and physiological indicators under drought stress conditions to evaluate the gene function. The bioinformatics analysis results showed that the full length coding sequence(CDS) of HvERECTA is 2 934 bp, encoding a protein of 977 amino acids. The HvERECTA protein is localized to the plasma membrane and contains a typical serine/threonine protein kinase domain, which is a hallmark of the receptor-like kinase family. Sequence alignment and phylogenetic analysis revealed that HvERECTA is highly conserved among gramineous plants, with the highest homology to those from wheat(Triticum aestivum) and ryegrass(Lolium perenne). Additionally, analysis of cis-acting elements in the HvERECTA promoter region indicated that it is rich in regulatory elements associated with abiotic stress responses and plant hormone signaling, such as abscisic acid(ABA)-responsive elements(ABRE) and drought-responsive elements(MBS). Phenotypic observations on the transgenic Arabidopsis lines showed that overexpression of HvERECTA significantly reduced stomatal density compared with the wild-type control. Molecular analysis demonstrated that the expression levels of genes encoding key stomatal development transcription factors, namely SPCH(SPEECHLESS), MUTE, and FAMA, were all downregulated by more than 50% in the transgenic lines. In contrast, the expression level of YODA, a core gene in the mitogen-activated protein kinase(MAPK) cascade pathway that is involved in stomatal development regulation, was upregulated by 50%-80% in the transgenic plants. Under drought stress, the transgenic Arabidopsis lines showed enhanced drought resistance-related physiological performance. Specifically, the activities of superoxide dismutase(SOD), peroxidase(POD), and catalase(CAT) in the transgenic lines were increased by 25%-40% compared with the control. Meanwhile, the content of malondialdehyde(MDA), which is an indicator of lipid peroxidation and cellular damage under stress, was decreased by approximately 30% in the transgenic lines. Additionally, the water loss rate of the transgenic lines was reduced by 20%, and their relative water content was higher than that of the control. Furthermore, the expression levels of stress-responsive genes, including AtKIN2, AtABF3, and AtRD22, showed no abnormal changes under normal growth conditions but were significantly upregulated under drought stress in the transgenic lines. In conclusion, the barley HvERECTA gene enhances plant drought resistance by regulating the MAPK signaling pathway to reduce stomatal density and by improving the activity of the plant antioxidant defense system. These two regulatory pathways collectively enhance the water retention capacity of plants under drought stress, thereby improving their stress tolerance. This study clarifies the important regulatory role of HvERECTA in stomatal development and abiotic stress response, and provides an important functional gene resource for drought-resistant molecular breeding of barley. |
|
查看全文 查看/发表评论 下载PDF阅读器 |
| 关闭 |
|
|
|
基本信息
