胡杨peu-miR129及其靶基因调控杨树干旱胁迫适应性的分子机制

我国水资源十分贫乏，培育强抗旱性、高效水分利用效率（WUE）植物新品种十分重要。我们前期从抗逆模式植物胡杨(Populus euphratica )中分离鉴定杨树特有的microRNA peu-miR129。本项目拟以peu-miR129介导的转录调控网络入手，通过鉴定在胡杨peu-miR129与候选基因的靶向关系；比较分析在干旱处理、ABA等外源信号诱导下胡杨peu-miR129、NAC等靶基因时空表达模式；遗传转化毛白杨（Popolus tomentosa）；Affymetrix 基因芯片技术分离peu-miR129及其靶基因调控的下游基因；研究peu-miR129及其靶基因在调控杨树抗旱节水性状中的潜在功能，探讨peu-miR129在ABA信号转导中可能发挥的作用，阐明胡杨适应干旱逆境特有的peu-miR129介导转录调控网络机制，为抗旱、高效WUE杨树新品种创制奠定理论与技术基础。

Water shortage is crucial problem in China. It is very important to produce new plant variety with high drought tolerance and high water use efficiency (WUE). We have previously identified Populus-special microRNA peu-miR129 from Populus euphratica. Transcriptional regulation network and functional characters of peu-miR129 in poplar adaptable to drought stress will be elucidated here. 5' RACE methods will be used to indentify of peu-miR129 target genes from candidate targets. Tissue and space specific expression pattern of peu-miR129 and target genes will be analyzed in Populus euphratica under drought and ABA treatment. Function of Poplar peu-miR129 and target genes in drought tolerance and high WUE will be examined by transferring peu-miR129 and target gene into Popolus tomentosa. We will use Affymetrix Poplar gene chip technique to analyze downstream genes regulated by peu-miR129 and gene promoter characteristics of key gene will be investigated. Possible role of peu-miR129 in ABA signal transduction will be discussed here. Our goal is to understand complex transcriptional regulatory network mediated by miRNA in poplar response to drought stress, and identify key genes in the regulation of WUE and drought tolerance. We expect to provide theory and technique basis for Poplar molecular breeding with high drought tolerance and high water use efficiency.