简单重复序列TTC调控AtHip1基因表达初探
Preliminary Analysis of AtHip1 Expression Modulated by a Simple Sequence Repeat TTC

拟南芥AtHip1基因启动子含有一个保守的TTC重复位点,序列预测该TTC位点与水杨酸应答元件相似。定量PCR分析表明AtHip1表达受水杨酸诱导,处理4 h后表达量达峰值,随后表达水平逐渐降低。构建5′端启动子系列缺失载体并转化拟南芥分析启动子功能。GUS染色和转基因表达分析显示AtHip1启动子-399至-184碱基(base pair,bp)位置的序列片段缺失导致启动子活性降低并丧失水杨酸应答功能。上述结果表明携带有TTC重复位点的启动子区段属AtHip1基因转录调控核心区且具有响应水杨酸信号的功能。
The promoter of AtHip1 gene contains a conserved TTC repeat locus.Sequence analysis showed that the repeats are similar to salicylic acid responsive elements.The qRT-PCR showed that the expression of AtHip1 reached highest 4 h after salicylic acid treatment and then decreased gradually.A serial of 5′-deleted promoter fragments of the AtHip1 gene were fused to the β-glucuronidase (GUS) reporter gene and transformed into Arabidopsis.The histochemcal assays of GUS activity and the expression level investigation of gus gene in transformed plants revealed that deleting AtHip1 promoter from -399 to -184 base pair (bp) significantly reduced the promoter activity and resulted in the loss of salicylic acid responsive function.Taken together,these results indicate that the TTC-repeat-containing region is important for gene transcription regulation and plays a critical role in the response to salicylic acid.