陸地棉響應干旱脅迫的擴展蛋白基因GhEXLB1功能分析

摘 要： 中國棉花主產區為新疆，該地區夏季晴熱少雨導致的干旱嚴重影響棉花纖維的產量和品質，挖掘陸地棉響應干旱的功能基因對培育棉花抗旱品種、保障棉花增產穩產具有重要作用。分析陸地棉干旱脅迫轉錄組數據，獲得陸地棉干旱脅迫響應基因GhEXLB1，并測定該基因響應干旱脅迫的表達模式；采用病毒誘導的基因沉默技術下調GhEXLB1表達量，并分析GhEXLB1沉默棉花的干旱脅迫相關的生理生化指標。結果表明：在陸地棉Expansin基因家族中，51個基因在干旱處理后表達差異顯著，其中42個上調表達，9個下調表達。GhEXLB1響應干旱脅迫明顯，表達水平相較干旱處理前變化最大，干旱處理6 h后該基因表達量較處理前升高了9.5倍；GhEXLB1下調表達植株對干旱脅迫的耐受性顯著低于對照植株，成活率約為45%；干旱脅迫下GhEXLB1沉默植株中活性氧清除系統相關酶活性顯著改變，與對照相比，GhEXLB1下調表達棉花丙二醛含量顯著上升、過氧化氫酶活性顯著上升、過氧化物酶和超氧化物歧化酶活性顯著降低。該結果為進一步挖掘棉花響應干旱脅迫功能基因和培育耐旱新品種提供了新的理論依據。

關鍵詞：陸地棉；表達模式；GhEXLB1；下調表達；干旱脅迫

中圖分類號：S330.2

文獻標志碼：A

文章編號：1673-3851 （2025） 03-0263-07

引文格式：錢多，古杰燕，柯麗萍，等. 陸地棉響應干旱脅迫的擴展蛋白基因GhEXLB1功能分析［J］. 浙江理工大學學報（自然科學），2025，53（2）：263-269.

Reference Format： QIAN Duo，GU Jieyan，KE Liping，et al. Functional analysis of expansin gene GhEXLB1 in response to drought stress in Gossypium hirsutum［J］. Journal of Zhejiang Sci-Tech University，2025，53（2）：263-269.

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

QIAN Duo， GU Jieyan， KE Liping， ZHAO Yanyan

（College of Life Sciences and Medicine， Zhejiang Sci-Tech University， Hangzhou 310018， China）

Abstract：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. Virus-induced 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.

Key words：Gossypium hirsutum; expression pattern; GhEXLB1; down-regulated expression; drought stress

0 引 言

棉花（Gossypium spp）是中國重要的經濟農作物之一，也是棉纖維紡織工業的主要原料，在醫藥、化工與國防等方面具有重要的價值。……