陆地棉响应干旱胁迫的扩展蛋白基因GhEXLB1功能分析  

Functional analysis of expansin gene GhEXLB1 in response to drought stress in Gossypium hirsutum

作　　者：钱多 古杰燕 柯丽萍 赵艳艳 QIAN Duo;GU Jieyan;KE Liping;ZHAO Yanyan(College of Life Sciences and Medicine,Zhejiang Sci-Tech University,Hangzhou 310018,China)

机构地区：[1]浙江理工大学生命科学与医药学院,杭州310018

出　　处：《浙江理工大学学报(自然科学版)》2025年第2期263-269,共7页Journal of Zhejiang Sci-Tech University(Natural Sciences)

基　　金：国家自然科学基金项目(32101683)。

摘　　要：中国棉花主产区为新疆,该地区夏季晴热少雨导致的干旱严重影响棉花纤维的产量和品质,挖掘陆地棉响应干旱的功能基因对培育棉花抗旱品种、保障棉花增产稳产具有重要作用。分析陆地棉干旱胁迫转录组数据,获得陆地棉干旱胁迫响应基因GhEXLB1,并测定该基因响应干旱胁迫的表达模式;采用病毒诱导的基因沉默技术下调GhEXLB1表达量,并分析GhEXLB1沉默棉花的干旱胁迫相关的生理生化指标。结果表明:在陆地棉Expansin基因家族中,51个基因在干旱处理后表达差异显著,其中42个上调表达,9个下调表达。GhEXLB1响应干旱胁迫明显,表达水平相较干旱处理前变化最大,干旱处理6 h后该基因表达量较处理前升高了9.5倍;GhEXLB1下调表达植株对干旱胁迫的耐受性显著低于对照植株,成活率约为45%;干旱胁迫下GhEXLB1沉默植株中活性氧清除系统相关酶活性显著改变,与对照相比,GhEXLB1下调表达棉花丙二醛含量显著上升、过氧化氢酶活性显著上升、过氧化物酶和超氧化物歧化酶活性显著降低。该结果为进一步挖掘棉花响应干旱胁迫功能基因和培育耐旱新品种提供了新的理论依据。Xinjiang is the primary cotton-producing region in China.Drought caused by hot and sunny summers with little rainfall in the region severely affects the yield and quality of cotton fibers.Mining the functional genes of Gossypium hirsutum in response to drought plays an important role in cultivating drought-resistant cotton varieties and ensuring cotton yield and stability.By analyzing the RNA-Seq data of Gossypium hirsutum under drought treatment,the drought stress response gene GhEXLB1 was obtained,and the expression pattern of the gene in response to drought stress was determined.Virusinduced gene silencing was used to down-regulate GhEXLB1 expression and drought stress-related physiological and biochemical indices in GhEXLB1-silenced cotton were analyzed.The result showed that 51 genes in the expansin gene family of Gossypium hirsutum were significantly differentially expressed after the drought treatment,42 differentially expressed genes(DEGs)were up-regulated,and nine DEGs were down-regulated.Among them,GhEXLB1 responded significantly to drought stress,with the greatest change in expression level compared with that before drought treatment,and the expression of this gene increased by 9.5-fold after 6 h of drought treatment compared with that before the treatment;the drought tolerance of GhEXLB1-silenced plants was significantly reduced than that of control plants,with a survival rate of about 45%.Reactive oxygen scavenging system-related enzyme activities were significantly altered in GhEXLB1-silenced plants under drought stress,with a significant increase in malondialdehyde content,a significant increase in catalase activity,and significant reductions in peroxidase and superoxide dismutase activities in GhEXLB1-silenced cotton as compared to the control.This study provides a new theoretical basis for further research on the identification of drought stress related genes and the breeding of drought-tolerant cotton varieties.

关 键 词：陆地棉 表达模式 GhEXLB1 下调表达 干旱胁迫 

分 类 号：S330.2[农业科学—作物遗传育种]