芥菜型油菜酵母单杂交系统的建立及调控BjTT8A表达的转录因子分离

Construction of Yeast-one Hybrid cDNA Library of Brassica juncea and Isolation of Transcription Factors Regulating BjTT8A Expression

BjTT8A基因是芥菜型油菜的类黄酮合成途径中重要的调控基因之一。为进一步分离调节BjTT8A基因表达的转录因子,建立了芥菜型油菜酵母单杂交cDNA文库,以BjTT8A的启动子构建诱饵融合载体,筛选cDNA文库,获得33个阳性克隆。序列分析结果表明,31个克隆与十字花科植物甘蓝型油菜,白菜,萝卜,荠菜的蛋白具有高度同源性,对其氨基酸序列进行同源比对和功能结构域分析,发现涉及光调控的捕光叶绿素a/b结合蛋白cp29.2,蛋白质积累的锌金属蛋白酶egy2,谷胱甘肽S-转移酶蛋白GSTF9等。研究结果为分离调控BjTT8A基因表达的转录因子提供了候选基因。

BjTT8A gene is one of the important regulatory genes in flavonoid synthesis pathway of Brassica juncea.In order to study the regulation mechanism of BjTT8A gene expression,the promoter of BjTT8A was used as bait in the yeast one hybrid system to isolate the underlying regulated factor from the cDNA library of B.juncea.Sequencing of the thirty-three isolated clones demonstrated that thirty-one were non repetitive sequences.Sequence analysis showed that thirty-one clones were highly homologous to the proteins of B.napus,B.rapa,Raphanus sativus and Capsella rubella.Analyzing the functional domain of the putative amino acid sequences showed that Homologous alignment and functional domain analysis of their amino acid sequences revealed that two protein involved in light regulation such as light-harvesting chlorophyll a/b binding protein cp29.2,zinc metalloproteinase egy2 and glutathione S-transferase GSTF9.The results provide candidate genes for isolating transcription factors regulating BjTT8A gene expression.