棉花中一个新的类DREB转录因子(GhDREB2B)的克隆、序列特征及表达分析  

Molecular cloning,characterization and expression of a novel DREB transcript factor GhDREB2B in cotton

作　　者：李付振[1] 邱新棉[1] 刘传亮[2] 

机构地区：[1]浙江省农业科学院作物与核技术利用研究所经济作物实验室,浙江杭州310021 [2]中国农业科学院棉花研究所农业部棉花遗传改良重点开放实验室,河南安阳455000

出　　处：《浙江农业学报》2010年第5期564-569,共6页Acta Agriculturae Zhejiangensis

基　　金：国家转基因生物新品种培育重大专项(2008ZX08010004;2008ZX0800500522);国家"863计划"(2006AA10Z1D2);浙江省自然科学基金(Y307558)

摘　　要：棉花是盐碱地改良的重要作物。文章利用盐胁迫处理棉花耐盐品种‘中棉所49’,筛选棉花EST数据库并对目标EST序列进行整合与分析,利用RT-PCR的方法,克隆了一个新的棉花类DREB转录因子,命名为GhDREB2B(GenBank登录号为GQ848094)。该基因编码351个氨基酸残基,分子量约39 kD,推导的氨基酸序列与杨树、番茄、大豆、拟南芥等物种中的DREB基因家族成员之间存在一定程度的同源性,均含AP2/ERF保守结构域,推测该基因在棉花中是一个新的DREB类转录因子。利用荧光定量RT-PCR对该转录因子表达特征的分析表明:GhDREB2B在棉花苗期经盐胁迫诱导后表达量迅速升高,在0.7%的NaC l胁迫诱导下,表达量达到最高值,但该转录因子并不受ABA的诱导。推测GhDREB2B在棉花受到干旱和盐胁迫条件下发挥重要功能。Cotton is an important crop in the reclamation of saline and alkaline land.In this study,a novel DREB（dehydration responsive element binding） transcript factor named GhDREB2B（GenBank accession No.GQ848094） was cloned from the upland cotton（Zhongmiansuo 49） by RT-PCR method based on the information of screening the cotton fiber EST（express sequence tag） database and contig the candidate ESTs under salt treatment.The full length of GhDREB2B encoded a polypeptide of 351 amino acid residues with a predicted molecular weight of 39 kD.The deduced amino acid sequences had the homology with the members of DREB family in plant kingdom： populus,soybean and Arabidopsis thaliana,etc.They shared the conserved domain of AP2/ERF in the deduced protein.This gene was predicted as a novel DREB factor in tetreploid cotton.Quantitative real-time RT-PCR analysis revealed that the higher expression levels of GhDREB2B gene were detected under salt treatment and its expression level was high under 0.7% NaCl treatment;however,its expression was not affected by the plant hormone of ABA（abscisic acid）.These results indicated that GhDREB2B gene plays an important role under salt tolerance and gives us the clues of using the factor in cotton by transgenic method.

关 键 词：棉花 DREB类转录因子 GhDREB2B 荧光定量 盐胁迫 ABA处理 

分 类 号：S562[农业科学—作物学] Q78[生物学—分子生物学]