菊花DgWRKYs转录因子功能鉴定及其抗盐机制解析

Chrysanthemum is a leading ornamental species in the world. The year-round production of cut chrysanthemum flowers in a heliogreenhouse often encounters high salinity because of the high irrigation frequency and high evapotranspiration in the north of China, which has severely inhibited cut flower growth and production.This study try to identify and functionally characterize the chrysanthemum DgWRKYs, obtain the 35S:DgWRKYs transgenic chrysanthemum, construct RNA-seq, DGE, ChIP-PCR, EMSA and bioinformatics for transgenic chrysanthemum with 35S:DgWRKYs construct and wild type chrysanthemum, and conclude the precise mechanism of DgWRKYs in high salinity tolerance. Thus, this study will provide a potentially excellent genetic resource for improving salt tolerance in chrysanthemum.

菊花是我国十大传统名花和世界四大切花之一，观赏和经济价值极高。目前切花菊主要通过集约化设施进行连作栽培，设施中土壤次生盐渍化严重影响菊花生产和品质。因而培育耐盐菊花新品种已成为切花菊育种的一个重要目标。本申请项目拟从菊花中分离DgWRKYs转录因子；采用Real-time PCR方法研究其在非生物胁迫下转录水平表达特性；利用超表达技术获得转35S:DgWRKYs基因菊花并对其开展抗盐性鉴定；以35S:DgWRKYs转化菊花和非转化菊花为材料, 综合利用RNA-seq、DEG、ChIP-PCR、EMSA技术和生物信息学方法，获得DgWRKYs在转录水平上调控盐胁迫响应的直接下游靶基因并对其进行功能分析，揭示DgWRKYs抗盐的转录调控机制。本申请项目的实施可为培育耐盐菊花新品种提供有效的基因储备。

菊花是我国十大传统名花和世界四大切花之一，其中切花菊是我国主要出口创汇花卉。设施中土壤次生盐渍化严重影响菊花生产和品质。因而培育耐盐菊花新品种已成为切花菊育种的一个重要目标。本项目按照项目计划书，课题组完成了以下研究内容：1.项目组获得DgWRKY5，发现该基因受NaCl、H2O2、GA和ABA诱导上调表达，其过量表达提高了转基因菊花的抗盐性。2.通过RNA-seq筛选，获得35S: DgWRKY5转化菊花较非转化菊花上调基因DgWRKY4和DgMBF1，进一步通过基因功能验证表明DgWRKY4和DgMBF1均能提高转基因菊花抗盐性。3.通过35S:DgWRKY4转化菊花与非转化菊花的RNA-seq筛选，获得上调基因DgWRKY2，该基因过量表达提高了转基因菊花的抗盐性。上述研究表明，DgWRKY5可为培育耐盐菊花新品种提供有效的基因储备。