羊草DREB转录因子的系统发育和功能研究  

Phylogeny and function characterization of DREB transcription factors in Leymus chinensis

作　　者：马兴勇[1,2] 彭献军[1,2] 苏蔓[1,2] 张乐新[1,2] 周庆源[1] 陈双燕[1] 程丽琴[1] 刘公社[1] 

机构地区：[1]中国科学院植物研究所资源植物研发重点实验室,北京100093 [2]中国科学院研究生院,北京100049

出　　处：《草业学报》2012年第6期190-197,共8页Acta Prataculturae Sinica

基　　金：国家重点基础研究发展计划(973计划)(2007CB108905);国家自然科学基金(31170316)资助

摘　　要：羊草是兼具经济价值和生态价值的重要牧草,具有耐寒、耐旱和耐盐碱的特点。在植物应对非生物胁迫的过程中,DREB转录因子起到关键作用。然而,目前在GenBank的核酸数据库和EST数据库中羊草仅有2条DREB序列,其中只有1个DREB基因的功能得到实验验证。本研究从羊草转录组测序数据中1次挖掘了26条DREBEST。用羊草EST和拟南芥基因组中DREB基因的蛋白序列构建了系统发育树,LcDREB21位于第4类群,是DREB2类转录因子基因。通过RACE,获得了LcDREB21编码区全长(Genbank登入号:JN860437)。荧光定量PCR结果表明,其表达受干旱和高盐诱导。另外,通过酵母单杂交实验证明了LcDREB21具有转录激活功能;通过表达GFP融合蛋白证明其专一性定位在细胞核中。总之,LcDREB21是一个具有转录激活功能和细胞核专一定位能力的转录因子,可能在植物应对干旱和高盐胁迫的过程中起作用。本实验结果丰富了羊草抗逆基因数据库,为植物改良提供了基因资源。Leymus chinensis is an economically and ecologically important grass that is tolerant to salt,drought and cold stresses.DREB are important transcription factors in plant stress responses.However,there were only two genes of L.chinensis in the GenBank nucleotide and EST databases and only one of them had further study.The identification of 26 L.chinensis DREB ESTs were reported from analysis of transcriptome sequencing data.A phylogenetic tree was inferred from protein sequences of the 26 L.chinensis DREB transcription factors compared with all DREB transcription factors in the Arabidopsis thaliana genome.LcDREB21 belonged to group IV,and was a member of DREB2s.RACE was used to amplify the full-length CDS of LcDREB21（GenBank accession number： JN860437）.qRT-PCR results confirmed that LcDREB21 was induced by drought and high salinity stresses.Transcriptional activation of LcDREB21 was shown by yeast one-hybrid system,and nuclear localization of LcDREB21 was confirmed by expression of GFP fusion.In summary,LcDREB21 showed nuclear specific localization and transactivation activity,and may play roles in response to drought and high salinity stresses of L.chinensis.New members have been added to the family of stress-related genes in L.chinensis,and LcDREB21 could be used to improve stress tolerance in plants through genetic engineering.

关 键 词：羊草 DREB 渗透胁迫 系统发育 

分 类 号：S543.9[农业科学—作物学]