采用染色体步移技术,从苦荞(Fagopyrum tataricum Gaertn.)中克隆获得FtCHS1基因5'端侧翼序列,共1038 bp,将其命名为PFtCHS1.生物信息学分析表明,PFtCHS1中A/T碱基含量为63.5％,含有4个可能的转录起始位点,分别位于起始密码子上游-684～-734、-692～-742、-920～-970、-929～-979 bp处,该序列包含TATA-Box和CAAT-Box等启动子核心元件以及与光、低温和激素应答等相关的功能元件.本研究进一步构建了PFtCHS1-pBI101植物表达载体,并瞬时转化拟南芥(Arabidopsis thaliana L.)叶片,结果显示该序列可驱动GUS报告基因的表达.低温(4℃)和光照(UV-B)处理苦荞幼芽后,采用荧光定量PCR技术分析FtCHS7基因的表达量,结果表明PFtCHS1可响应低温和紫外环境胁迫,从而引起FtCHS1基因表达量发生变化.%Through genome walking,a 5'flanking sequence of the chalcone synthase gene,1038 bp in length,was cloned from tartary buckwheat (Fagopyrum tataricum Gaertn).Bioinformatics analysis showed 63.5％ of adenine and thymine in the sequence.Four potential transcription starting sites were located at-684--734 bp,-692--742 bp,-920--970 bp,and-929--979 bp,respectively,which not only contained promoter elements such as TATA-Box and CAAT-Box,but also functional elements related to light,low temperature,and hormone responses.In this study,the plant expression vector was further constructed and transformed into Arabidopsis thaliana L.leaves,and results showed that the sequence could drive the expression of the GUS reporter gene,and was thus named as promoter PFtCHS1.The tartary buckwheat sprouts were then treated by low temperature (4℃)and UV-B light,with PFtCHS1 shown to respond to the temperature and light treatment,which resulted in a change in FtCHS1 gene expression.
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