低温冷害是我国辣椒冬春育苗和保护地生产的主要障碍因素，而脱水素在植物低温胁迫中起着重要作用。项目组前期研究发现辣椒脱水素家族含有7个成员，其中CaDHN1和CaDHN4受低温强烈诱导，且抗寒材料上调倍数显著高于低温敏感材料，但其是否具有抗寒功能及调控机理是什么尚不清楚，因此本项目拟以抗寒辣椒品系P70及不抗寒辣椒B8为材料，采用转基因的方法，比较VIGS诱导基因沉默及超量表达CaDHN1和CaDHN4基因后转基因植株在低温胁迫中的表现差异，明确基因功能；同时采用启动子活性分析、酵母单杂技术及RNA-Seq技术，获得CaDHN1和CaDHN4基因上游关键调控因子及低温胁迫下超量表达与对照植株的基因表达变化，阐明CaDHN1和CaDHN4基因在辣椒抗寒中的调控机理。通过以上研究有望为更全面、更深入地揭示辣椒乃至其他植物的抗寒机制作出贡献，同时也可为辣椒及其他作物抗逆分子育种提供新的基因来源。

Low temperature is one of the major obstacle factor of pepper winter and spring seeding and protection production in our country. DHN proteins play an important role in cold stress. In the previous research we have identified 7 DHN genes in pepper genomic, and the CaDHN1and CaDHN4 genes were strong induced by low temperature. Moreover the up-regulated degree in cold resistance pepper was higher than that of sensitive pepper. However, Whether the CaDHN1and CaDHN4 genes have the cold resistance function and what are the regulation mechanism is still not clear. So in this project we will use the cold resistant pepper line P70 and cold sensitive pepper line B8, utilize the transgenic approach, compare the performance of gene transgenic plants which overexpression and silence CaDHN1 and CaDHN4 in low temperature stress and identified the CaDHN1 and CaDHN4 gene function. At the same time, we will use the promoter activity analysis, yeast one hybrid technology and RNA SEQ technology to identify the upstream and downstream key regulation factors of CaDHN1 and CaDHN4 genes, and elucidate cold resistance regulation mechanism in pepper. Through these research, the results would provide the scientific foundation for recognizing the mechanism of the DHN gene in stress tolerance. Also, they will provide a useful way and new material for stress tolerance breeding about pepper and other crops.