桂花OfFCA基因的克隆及在花芽分化时期的表达分析  

Cloning and expression analysis of OfFCA gene at flower bud differentiation stages in Osmanthus fragrans

作　　者：吴琪 吴鸿飞 周敏舒 徐倩霞 杨丽媛 赵宏波[1] 董彬[1] WU Qi;WU Hongfei;ZHOU Minshu;XU Qianxia;YANG Liyuan;ZHAO Hongbo;DONG Bin(School of Landscape Architecture,Zhejiang A&F University,Hangzhou 311300,Zhejiang,China)

机构地区：[1]浙江农林大学风景园林与建筑学院,浙江杭州311300

出　　处：《浙江农林大学学报》2020年第2期195-200,共6页Journal of Zhejiang A&F University

基　　金：浙江省教育厅一般项目(Y201839931);浙江农林大学科研发展基金项目(2017FR016)。

摘　　要：【目的】桂花Osmanthus fragrans是著名的香化植物,其花芽分化受到环境温度影响。研究环境温度对桂花花芽分化的影响对桂花的花期调控具有重要的指导意义。【方法】以桂花品种‘堰虹桂’O.fragrans‘Yanhonggui’为材料,采用石蜡切片观察其花芽分化进程,运用聚合酶链式反应和实时荧光定量技术对影响温度FCA(FLOWERING LOCUS CA)基因分别进行克隆及表达特异性分析。【结果】克隆得到OfFCA cDNA序列长为1319 bp,其开放阅读框为864 bp,编码287个氨基酸。序列比对及进化分析发现:OfFCA与木犀科Oleaceae油橄榄Olea europaea和胡麻科Pedaliaceae芝麻Sesamum indicum的FCA相似度较高,同源性可达68%以上。在桂花花芽分化的不同时期,无论叶还是花芽中,19℃环境低温下OfFCA基因的表达水平均显著高于25℃常温生长条件下的表达水平。【结论】桂花OfFCA基因响应环境相对低温的变化,参与桂花的花芽分化,使桂花的花期提前。[Objective]Sweet osmanthus(Osmanthus fragrans)is widely used in gardening as a fragrant plant.Its flower bud differentiation is significantly affected by ambient temperature.This research aims to find out the working mechanism of ambient temperature on the flower bud differentiation to help regulate flowering period of sweet osmanthus.[Method]Gene FCA(FLOWERING LOCUS CA)was studied using O.fragrans‘Yanhonggui’as the material,the process of flower bud differentiation was observed by paraffin section,and OfFCA was cloned and expression analysis was made by PCR and real-time PCR.[Result]The sequence length of OfFCA cDNA obtained by cloning was 1319 bp,the Open Reading Frame(ORF)length was 864 bp,and 287 amino acids were encoded.Amino acid sequence alignment and evolutionary analysis showed that OfFCA was similar in FCA to Olea europaea,Oleaceae and Sesamum indicum,Pedaliaceae,with a homology of over 68%.The real time PCR demonstrated that the expression of OfFCA gene was higher at the low temperature(19℃)treatment than control temperature(25℃)in both leaves and flower buds at different flower bud differentiation stages.[Conclusion]Our work lay a foundation for the studying of regulating flowering time of O.fragrans by ambient temperature.

关 键 词：林木育种学 桂花 FCA基因 花芽分化 基因表达 

分 类 号：S722.3[农业科学—林木遗传育种]