与 AtGA20ox1启动子结合的转录因子筛选分析

摘要

Gibberellin (GA ) plays an important role in plant growth and development.Gibberellin 20-oxidase (GA20ox)is the key enzyme in the pathway of GA biosynthesis,so it is important to find the transcription factors that regulate the expression of GA20ox to reveal the mechanism underline GA metabolism and its regulation.In this study, AtGA20ox1 promoter was used to screen Arabidopsis transcription factor library by yeast one hybrid,and the transcription factor RAP2.4f was selected.Yeast one hybrid and X-gal assay results further confirmed that RAP2.4f can bind to the promoter of AtGA20ox1.CPRG quantitative analysis showed that their binding activity was very strong.Dual luciferase assay showed that RAP2.4f inhibited the AtGA20ox1 promoter activity.These results indicated that RAP2.4f might regu-late the transcription of AtGA20ox.%赤霉素（gibberellin，GA）在植物生长发育的各个时期发挥重要作用。GA20-氧化酶（Gibberellin20-oxi-dase，GA20ox）是赤霉素生物合成途径中关键的限速酶，因此研究调控 GA20ox 基因表达的转录因子对进一步阐述赤霉素生物合成及其调控具有重要意义。本研究通过酵母单杂交技术利用 AtGA20ox1启动子筛选拟南芥转录因子库，筛选获得转录因子 RAP2．4f；酵母单杂交和 X-gal 显色结果进一步证实 RAP2．4能与 AtGA20ox1启动子结合；CPRG 定量分析发现 RAP2．4f 与 AtGA20ox1启动子结合作用强；双荧光素酶检测结果显示 RAP2．4f 对AtGA20ox1的启动子活性具有抑制作用。这些研究结果表明，RAP2．4f 可能参与调控 AtGA20ox1的转录。