Biotechnology Research Institute/National Key Facility for Crop Gene Resources and Genetic Improvement, Chinese Academy of Agricultural Science, Beijing 100081, China.
Sci China Life Sci. 2010 Nov;53(11):1315-21. doi: 10.1007/s11427-010-4079-0. Epub 2010 Nov 3.
The protein kinase AtMPK3, a component of the MAP kinase cascade, plays an important role in stress signal transduction in plant cells. To clarify how AtMPK3 is regulated at the transcriptional level in response to various environmental factors, the 1016-bp promoter sequence upstream of the transcription start site of the AtMPK3 gene was isolated. Analyses of the promoter sequence using plant promoter databases revealed that the AtMPK3 promoter contains many potential cis-acting elements involved in environmental stress responses. We constructed four deletion mutants of the AtMPK3 promoter, and introduced the intact and truncated promoter sequences fused to the β-glucuronidase (GUS) gene into Arabidopsis. GUS histochemical staining and quantitative fluorometric GUS assays were performed to visualize and compare the expression patterns in response to different environmental stimuli. The region between -188 and -62 upstream of the transcription start site was identified as the essential DNA sequence of the AtMPK3 promoter for responses to drought, high salinity, low temperature, and wounding. These results advance our understanding of the molecular mechanisms controlling AtMPK3 expression in response to different environmental stimuli.
蛋白激酶 AtMPK3 是 MAP 激酶级联反应的一个组成部分，在植物细胞的应激信号转导中发挥着重要作用。为了阐明 AtMPK3 如何在转录水平上被各种环境因素调控，我们分离了 AtMPK3 基因转录起始位点上游的 1016bp 启动子序列。使用植物启动子数据库对启动子序列进行分析表明，AtMPK3 启动子含有许多参与环境胁迫响应的潜在顺式作用元件。我们构建了 AtMPK3 启动子的四个缺失突变体，并将完整和截断的启动子序列与β-葡萄糖醛酸酶（GUS）基因融合，导入拟南芥。通过 GUS 组织化学染色和定量荧光 GUS 分析，可视化并比较了对不同环境刺激的表达模式。结果表明，转录起始位点上游的-188 到-62 区域是 AtMPK3 启动子响应干旱、高盐、低温和创伤所必需的 DNA 序列。这些结果提高了我们对控制 AtMPK3 表达以响应不同环境刺激的分子机制的理解。
