Center for Agricultural Biotechnology, Shanxi Agricultural University, Taigu 030801, China.
J Plant Physiol. 2009 Dec 15;166(18):2046-57. doi: 10.1016/j.jplph.2009.06.011. Epub 2009 Jul 22.
MicroRNAs (miRNAs) play vital roles in down-regulating gene expression at the post-transcriptional level. A set of 24 UV-B stress-responsive miRNAs (13 up-regulated and 11 down-regulated) was identified in Populus tremula plantlet by expression profiling with our in-house miRNA filter array. Six of the UV-B-responsive miRNA and their corresponding target genes were verified for their expressions by RNA blotting and quantitative reverse transcription PCR (qRT-PCR), respectively. The predicted target genes for these miRNAs encode diverse proteins including transcription factors and phytohormone signal-related proteins. Promoter analysis of the UV-B-responsive miRNAs revealed the presence of many light-relevant cis-elements. However, these cis-elements were not necessarily specific to the promoters of UV-responsive miRNAs, indicating that other machinery may be involved in the regulation of UV-responsive miRNAs. Finally, a model was developed to describe the potential regulatory networks mediated by the UV-B-responsive miRNAs in P. tremula. These results provide new insights into the understanding of miRNAs as ubiquitous regulators in plant response to UV-B and other stresses.
MicroRNAs (miRNAs) 在转录后水平下调基因表达中发挥着重要作用。通过使用我们内部的 miRNA 筛选阵列进行表达谱分析，在白杨植物中鉴定出了一组 24 个对 UV-B 应激有反应的 miRNA（13 个上调和 11 个下调）。通过 RNA 印迹和定量逆转录 PCR（qRT-PCR）分别验证了 6 个 UV-B 反应性 miRNA 及其相应的靶基因的表达。这些 miRNA 的预测靶基因编码多种蛋白质，包括转录因子和植物激素信号相关蛋白。对 UV-B 反应性 miRNA 的启动子分析表明存在许多与光相关的顺式元件。然而，这些顺式元件不一定是 UV 反应性 miRNA 启动子所特有的，这表明可能涉及其他机制来调节 UV 反应性 miRNA。最后，提出了一个模型来描述 UV-B 反应性 miRNA 在 P. tremula 中介导的潜在调控网络。这些结果为理解 miRNA 作为植物对 UV-B 和其他胁迫反应的普遍调控因子提供了新的见解。
