月季HD-ZipI和II转录因子整合激素信号调节花瓣扩展与衰老的机制解析

项目名称： 月季HD-ZipI和II转录因子整合激素信号调节花瓣扩展与衰老的机制解析

项目编号： No.31471903

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 农业科学

项目作者： 高俊平

作者单位： 中国农业大学

项目金额： 95万元

中文摘要： 月季是全球第一大切花，其开放品质主要依赖于花瓣扩展程度和衰老速度。已经明确，乙烯能够加速花朵开放和衰老进程，同时抑制花瓣细胞扩展，导致花朵开放异常；赤霉素（GAs）具有与乙烯相反的效果，能够延缓花朵衰老进程，改善开放品质。但是，迄今为止乙烯和GAs信号之间的相互作用方式及其对花朵开放和衰老的调节机制尚不清楚。已有报道表明，HD-Zip转录因子家族中I和II亚家族成员是激素信号互作的重要节点之一。申请者的前期工作，从月季花器官转录组数据库中筛选到11个HD-ZipI 和II基因。本项目拟对这些成员在花瓣扩展和衰老中的功能进行鉴定，对其中重要成员介导乙烯和GAs信号相互作用的方式进行分析，并对其上下游基因调节网络进行解析。以期从转录调节的层面上初步阐明HD-ZipI和II亚家族成员整合激素信号，调节月季花瓣扩展和衰老的分子机制，进而为月季切花开放品质改良提供新的基因资源。

中文关键词： 月季；花朵开放和衰老；HD-zip转录因子；激素信号；信号互作

英文摘要： Rose is one of the most important cut flower in the global market. The economic value of rose is largely depended on the flower opening quality, which is decided by petal expansion and senescence. It is clear that the ethylene can accelerate the process of flower opening and suppress the petal expansion, and thus lead to abnormal petal and shortened vase life. On the other hand, Giberillin acids (GAs) are able to delay flower senescence and improve the opening quality. To date, however, it is less known concerning how ethyene and GAs integradedly regulate the flower opening and senescence. Previously, HD-Zip transcription factors were reported to be involved in mediating phytohormone cross-talk. Recently, we isolated 11 HD-Zip I and II subfamily genes by searching our rose floral transcriptome database. In this project, we will firstly identify the function of these genes in petal expansion and senescence of rose flower using VIGS approach. The candidate genes which are likely contribute petal expansion and senescence will be further confirmed by overexpression or silencing in rose plants. And then, the selected gene will be characterized biochemically and genentically. The regulatory network downstream to candidate gene will be identified by screening the RNA-seq data generated from control and transgenic rose plants overexpressed candidate gene. Moreover, we will investigate the possible role of the candidate genes in integrading ethylene and GA signaling during petal expansion and senescence through identification of possible upstream regulators of candidate genes. We anticipate that our work could dissect the molecular mechanism that regulation of petal expansion and senescence in rose by HD-Zip I and II-integrated phytohormones signaling.

英文关键词： rose;flower opening and senescence;HD-Zip transcription factor;hormone signaling;signaling crosstalk