我国水资源严重匮乏限制了城市绿化，制约着草坪绿地的建设和高水平发展。克隆植物抗旱基因，培育抗旱草坪草新品种是推动我国草坪发展水平的根本途径。脱水素是植物中发现的一种重要抗逆蛋白，与植物的抗旱能力密切相关。申请人所在研究组在研究八个不同狗牙根品种的抗旱性能时发现，脱水素蛋白与狗牙根抗旱有着密切关系，其中一脱水素基因与大麦脱水素蛋白DHN4基因相似性极高。本课题拟从抗旱的狗牙根中克隆脱水素基因CdDHN4，并对该基因的表达调控，细胞定位及抗旱功能进行分析。主要研究内容包括：CdDHN4基因cDNA全长的克隆；启动子克隆；CdDHN4基因组织表达和诱导表达分析，CdDHN4细胞定位及CdDHN4基因的抗旱功能分析，以期获得一个新的、具有明显抗旱功能的脱水素基因，明确其表达模式及基因的调控通路，为进一步研究脱水素基因参与抗旱的生理和分子机制、培育抗旱草坪草新品种奠定基础。

Freshwater resource in our country is very deficient, which limits the development of urban afforesting and greening espicially the lawn construction. Cloning drought-tolerance gene from plants, transforming them to turf to enhance turfs' tolerance, and cultivating new drought-tolerance varieties are the basic way to advance lawn cause. .Dehydrin is one of the important stress-tolerance protein found in plants. It was reported that dehydrin is intimately related to stress tolerance of plants. This project is planed to clone a dehydrin gene and character its function. The gene was named CdDHN4. It was first found significantly up-regulated in a drought-tolerance genotypy of bermudagrass-'Tifway' after 10 days waterless. But in the drought-sensitive genotypy-'C299', its expression is much lower than in 'Tifway' under water stress. This is hinting CdDHN4 may relate to drought tolerant of 'Tifway'. In this project we will clone the whole CdDHN4 including its promoter, analysis its expression modle and cellular localization, and make sure that it can really enhance plant drought tolerance. We planed to use transgenic technology and RNA interference technology to confirm CdDHN4's function of drought tolerance. .With these work, we want to obtain a neval drought-tolerance dehydrin gene and make sure of its regulation pathway and reveal the molecular mechanism of drought tolerance related to dehydrin. All these work will be useful for further cultivating drought-tolerance varieties of turfs.