DREB1A类转录调控域中对转录激活功能起关键作用的氨基酸  

Crucial Amino Acids in Transcription Regulatory Domain for DREB1A-like Transcription Activation

作　　者：刘卫群[1] 冯锋[1] 郭红祥[1] 陈红歌[1] 赵同金[2] 周海梦[2] 

机构地区：[1]河南农业大学生命科学学院,郑州450002 [2]清华大学生物科学与技术系,北京100084

出　　处：《中国生物化学与分子生物学报》2008年第2期134-141,共8页Chinese Journal of Biochemistry and Molecular Biology

基　　金：河南省科技攻关项目(No.0624050012)~~

摘　　要：从烟草品种k326中克隆到2个干旱应答元件结合蛋白类(DREB-Like)转录因子基因,命名为NtDREBI和NtDREB1A.序列分析发现,NtDREBI和NtDREB1A编码的蛋白质具有典型的AP2/EREBP转录因子家族EREBP亚族A类特征.酵母单杂交结果显示,NtDREBI具有激活功能,而NtDREB1A不能激活下游基因,但可以与DRE元件结合.将NtDREBI、NtDREB1A与其它AP2/EREBP类转录因子序列比对,发现在C末端第148位氨基酸有显著差别.采用定点突变方法进一步研究表明,DREB1A类转录因子的第148位氨基酸残基与其邻近氨基酸残基的相互作用对调控转录激活功能起关键作用.Two dehydration-responsive element binding protein （DREB）-Iike transcription factor genes were cloned from tobacco K326 （Nicotiana tabacum ）, and named as NtDREBI and NtDREB1A, respectively. Proteins encoded by NtDREBI and NtDREB 1A possessed the typical structural characteristics of A-type of EREBP subgroup in the AP2/EREBP transcription factor family as indicated by sequence analyses. The results of yeast one-hybrid assay showed that NtDREBI could activate the expression of downstream genes, whereas NtDREB1A only bound to DRE cis-element but was not functional. Compared with other AP2/EREBP transcription factors, the 148th amino acid residue at C-terminus was non-conserved. Further site-directed mutagenesis indicated that the interaction of this 148th amino acid residue of DREB1A transcription factors with its neighboring residues play a crucial role in the transcription activation function.

关 键 词：DREB转录因子 转录激活 酵母单杂交 关键氨基酸 

分 类 号：Q78[生物学—分子生物学]