光周期敏感性是影响热带玉米种质利用的主要障碍，分离、克隆及对光周期敏感性相关基因的功能研究具有重要意义。本课题组在初步定位的基础上，构建了玉米第4染色体光周期敏感性主效QTL qDPS4的近等基因系，对其进行了精细定位，获得了候选基因ZmFKF1。本项目拟对该基因进行深入研究，主要包括：(1)克隆双亲及近等基因系ZmFKF1的CDS，启动子及基因组DNA序列，比较其序列差异，并分析该基因在不同光周期条件下的时空表达模式；(2)利用crispr-cas9系统构建ZmFKF1基因敲除载体，同时构建ZmFKF1过表达载体，通过遗传转化获得ZmFKF1基因敲除和过表达转基因株系，验证ZmFKF1功能；(3)利用亚细胞定位，pull-down，荧光素酶互补等技术探究ZmFKF1的分子作用机制。本研究将为全面解析玉米光周期调控开花的分子机制提供理论依据，对玉米遗传改良及拓宽我国玉米种质资源有重要意义。

Photoperiod sensitivity is the main obstacle of the usage of tropical germplasms in temperate zone. So, identification, cloning and functional analysis of genes related to photoperiod sensitivity have significant value in theory and practice of agriculture. Based on the QTL analysis, the near-isogenic lines of QTL qDPS4 were constructed for the fine mapping, and then we obtained a candidate gene ZmFKF1 of a major QTL qDPS4 for photoperiod sensitivity. In order to understanding the function of ZmFKF1 in the photoperiod pathway，this study will mainly focus on three aspects: (1) cloning and analyze the sequences of CDS, promoter and genomic DNA of ZmFKF1，and analyze the expression pattern of ZmFKF1 under different photoperiodic induction in huangzao 4, CML288 and near-isogenic lines simultaneously; (2) construct two plasmids: one is knock-out of the ZmFKF1 by crispr-cas9 technology, the other is overexpress of the ZmFKF1, and validate the ZmFKF1 function by transgenic technology and phenotypic analysis of transgenic lines; (3) investigate the molecular workings of ZmFKF1 by some biochemical assays, including sub-cellular localization, pull-down, firefly luciferase complementation imaging assay. This study will prove new theories for comprehensive analytic molecular workings of photoperiod pathway in maize, and provide more information for abundance of maize germplasm and maize genetic improvement in China.