大豆伪应答因子GmPRR7在光周期调控开花途径的功能及分子机制

Flowering time is one of most important factors of agronomic traits, which effects on crop yield, plant morphogenesis, ecological adaptability and so on. As crop of photoperiod sensitivity soybean’s flowering time is regulated by photoperiod, which limits its adaptability. Up to date, although 11 genes of flowering time and maturity have been cloned, the molecular mechanism of photoperiod regulation flowering time in soybean is not clear. In our previous study, we found a rhythm expression gene GmPRR7 by fine mapping. The function of this gene in pathway of photoperiod regulation flowering time in soybean has not yet been reported. In this project, we will elucidate function of flowering repressor GmPRR7 in flowering time via functional complementation. On expression level, known flowering time and maturity genes will be analyzed to locate GmPRR7 in photoperiod pathway. RNA-Seq, EMSA, ChIP, yeast two-hybrid and BiFC will be used to screen and identify downstream genes regulated directly by GmPRR7 and interactional proteins. Molecular network will be constructed to elucidate the molecular mechanisms of photoperiod about GmPRR7 in soybean. Conducting of this project will uncover the molecular mechanisms of photoperiod which will provide a potential new component for molecular design breeding in soybean.

开花是作物最重要农艺性状之一，直接影响作物产量、植株形态建成及生态适应性等方面。开花受光周期调控，大豆的光周期敏感性严重限制了大豆的生态适应性。虽然已有11个大豆开花及成熟期基因相继被克隆，但大豆光周期调控开花机制仍不明晰。申请者前期研究中精细定位到节律性表达的大豆开花相关基因GmPRR7，目前尚没有该基因在光周期调控开花途径中的分子机制报道。本项目拟通过功能互补实验验证其在大豆开花中的功能；在表达水平分析GmPRR7与已知大豆光周期基因相互调控关系，明确GmPRR7在光周期途径的位置；利用转录组测序、凝胶阻滞、染色质免疫沉淀、酵母双杂、双分子荧光互补等技术筛选确定GmPRR7调控的下游基因及与其相互作用的蛋白，构建分子调控网络，解析GmPRR7在光周期调控途径的分子机制。GmPRR7的研究将有助于对大豆光周期敏感性的认识，为大豆分子设计育种提供新的靶点和分子元件。

开花是作物最重要农艺性状之一，直接影响作物产量、植株形态建成及生态适应性等方面。大豆的光周期敏感性严重限制了大豆的生态适应性。虽然已有部分大豆开花及成熟期基因相继被克隆，但大豆光周期调控开花机制尚未完全解析。本项目对前期发现的大豆开花基因GmPRR7进行深入研究，完善光周期调控大豆开花网络途径。本项目构建过表达及基因编辑载体，通过遗传转化获得后代阳性株系，鉴定表型明确GmPRR7是大豆开花途径的重要基因，具有延迟开花的功能；进一步通过节律性表达分析，明确GmPRR7是生物钟基因，是生物钟中央振荡器的核心成员；通过对COPs、LCLs、COLs等开花相关基因的表达分析，揭示了COPs、LCLs是GmPRR7的下游调控基因；通过酵母双杂及双分子荧光互补实验证实GmPRR5/9s与GmPRR7蛋白存在互作关系，且作用在细胞膜上。GmPRR7 基因的深入研究添补了大豆光周期调控开花网络的重要组成部分，对大豆生育期研究及后继分子设计育种均具有重大意义。