玉米ZmCOL3pro217启动子的克隆及功能分析

Cloning and Functional Analysis of ZmCOL3pro217 Promoter in Maize

ZmCOL3是玉米开花期光周期调控网络中一个重要的功能基因,研究发现自然群体中该基因的启动子存在遗传变异,推测这些变异可能参与玉米开花调控。研究从热带血缘玉米材料CIMBL119中克隆了ZmCOL3启动子,命名为ZmCOL3pro217。序列比对发现,该启动子序列与温带血缘玉米B73序列存在1个217 bp大片段置换。生物信息学分析表明,ZmCOL3pro217含有分生组织特异性、光响应、胁迫响应等多个顺势作用元件,预测ZmCOL3pro217可能具有组织特异性,并通过响应光和胁迫反应参与玉米开花调控。进一步构建ZmCOL3pro217驱动gus报告基因表达载体,转化玉米,实时荧光定量PCR、酶联免疫吸附剂测定、GUS组织化学染色等研究结果发现,转基因植株中ZmCOL3pro217驱动gus基因在根和叶器官中高表达,而在茎、花丝和子粒中几乎不表达,证实ZmCOL3pro217是1个新的组织特异性表达启动子。

ZmCOL3 is a crucial functional gene in the photoperiod regulation network of maize at flowering stage. Previous studies observed that ZmCOL3 exhibited diverse genetic variations in its promoter region in maize natural populations, suggesting that the promotor might be of importance in ZmCOL3 functionality. In this study, ZmCOL3 promoter(designated as ZmCOL3 pro217) was cloned from a tropical maize variety CIMBL119. In comparison with maize B73 reference genome, it is revealed that the promoter has a large fragment replacement of 217 bps. And the study further constructed gus reporter gene driven by ZmCOL3 pro217 and transformed it into maize through agrobacterium-mediated transformation. The results of real-time PCR, ELISA, and GUS assay proved that ZmCOL3 pro217 was a tissue-specific promotor with the highest expression observed in roots and leaves.