棉花抗枯萎病相关转录因子基因的克隆与表达  

Cloning and Expression of a Transcription Factor Gene Related to Cotton Resistance to Fusarium oxysporum f.sp.vasinfectum

作　　者：李潇玲[1] 张析[1] 郭文婷[1] 张鹏飞[1] 张薇[1] 

机构地区：[1]石河子大学农学院,新疆石河子832000

出　　处：《西北植物学报》2017年第1期67-73,共7页Acta Botanica Boreali-Occidentalia Sinica

基　　金：国家自然科学基金(31260358;31560407)

摘　　要：以枯萎病菌诱导棉花基因表达谱中获得的差异表达bZIP作为探针,采用电子克隆结合RT-PCR方法从棉花抗枯萎病品种‘中棉所12’中克隆了1个TGA转录因子基因,命名为GhTGA2.2。序列分析表明,该基因的cDNA全长1 356bp,编码451个氨基酸,预测分子量为50.04kD,等电点为5.85,含有保守的bZIP结构域。系统进化树分析表明,GhTGA2.2属于bZIP亚家族的TGA转录因子,与拟南芥AtTGA2、烟草NtTGA2.2亲缘关系最近。qRT-PCR分析表明,经枯萎病菌诱导后,GhTGA2.2基因在抗病品种中呈上调表达,随处理后时间的推移,其相对表达量呈先升高后降低的趋势,并于处理后24h表达量达到最大;水杨酸诱导后1h,GhTGA2.2基因相对表达量迅速增加;茉莉酸和乙烯诱导后GhTGA2.2基因的相对表达量明显降低,呈下调表达。研究推测,GhTGA2.2基因可能通过水杨酸信号传导途径参与对枯萎病菌的防御反应。In this study, the bZIP gene fragment from a digital expression profiling of cotton root tissue infected by Fusarium oxysporum f. sp. vasinfectum （Fov） was cloned from the roots of Zhongmiansuo 12 through the in silico cloning and RT PCR, named as GhTGA2.2 （Genebank： KY069278）. Sequence analysis showed that the cDNA of GhTGA2.2 gene was 1 356 bp, which encoded a protein of 452 amino acids containing a conserved bZIP domain with predicted molecular weight of 50.04 kD and an isoelectric point of 5.85. Phylogenetic analysis revealed that GhTGA2.2 belonged to the TGA transcription factors of the bZIP subfamily and was related closely to AtTGA2 of Arabidopsis thaliana and NtTGA2.2 of Nicotiana tabacum. qRT PCR analysis indicated that, the relative expression of GhTGA2.2 increased in the resistant cultivar after the treatment of Fov. The expression level increased first and decreased then with the treatment time going on, and the expression level reached the highest at over 24 hours after treatment; After the treatment of salicylic acid, the level of GhTGA2.2 expression reached rapidly the maximum at 1 h. While the relative expression of GhTGA2.2 decreased after the ethylene and jasmonic acid treatments; we speculated that GhTGA2.2 may involve in salicylic acid signal pathway to defense Fov.

关 键 词：棉花 TGA转录因子 枯萎病菌 GhTGA2.2 克隆表达 

分 类 号：Q785[生物学—分子生物学] Q786