荷兰鸢尾‘玉妃’花色变异关键结构基因分析  

Analysis of Key Genes About Flower Color Variation in Iris hollandica

作　　者：林兵[1] 陈艺荃 钟淮钦[1] 叶秀仙[1] 樊荣辉[1] LIN Bing;CHEN YiQuan;ZHONG HuaiQin;YE XiuXian;FAN RongHui(Institute of Crop Sciences,Fujian Academy of Agricultural Science,Fuzhou 350013;Institute of Agriculture and Engineering Technology,Fujian Academy of Agricultural Science,Fuzhou 350013)

机构地区：[1]福建省农业科学院作物研究所,福州350013 [2]福建省农业科学院农业工程技术研究所,福州350013

出　　处：《中国农业科学》2021年第12期2644-2652,共9页Scientia Agricultura Sinica

基　　金：福建省省属公益类科研专项(2018R1026-6);福建省农业科学院科技创新团队项目(STIT2017-2-9);福建省自然科学基金(2018J01045)。

摘　　要：【目的】花色变异对丰富观赏植物花色具有重要意义,但由于花色变异的不确定性,使其变异机理尚未弄清。荷兰鸢尾是重要球根观赏植物,通过探索荷兰鸢尾蓝紫色野生型‘展翅’及白色突变株‘玉妃’的显色分子机制及色素积累差异,为花色变异机理提供依据。【方法】本研究通过超高效液相色谱-四级杆飞行时间串联质谱联用(UHPLC-QTOF-MS)方法测定荷兰鸢尾2个品种花的花色素苷和黄酮醇的种类及含量。以荷兰鸢尾‘展翅’和‘玉妃’的旗瓣为材料,通过转录组测序,筛选花色素苷合成相关差异基因。以2个品种花发育不同时期为材料,对差异基因进行荧光定量PCR验证。【结果】代谢组分析结果表明,飞燕草素和矢车菊素及其衍生物在蓝紫色花中积累,在白色花中几乎没有积累,而黄酮醇类物质在白色‘玉妃’中含量上升。RNA-seq结果表明,共获得46485个unigenes,其中27073个unigenes被公共数据库功能注释,占全部unigenes的58.24%。获得701个差异表达基因,其中485个基因在‘玉妃’中上调表达,216个基因在‘玉妃’中下调表达。花色素苷途径中,2个二氢黄酮醇-4-还原酶(dihydroflavonol 4-reductase,DFR)基因和1个黄酮醇合成酶(flavonol synthase,FLS)基因有差异表达,分别命名为IhDFR1、IhDFR2和IhFLS1。白色‘玉妃’中,IhDFR1和IhDFR2下调表达,IhFLS1上调表达,导致花色素苷含量显著降低和黄酮醇积累,使代谢流由花色素苷转向黄酮醇。3个基因的qRT-PCR结果显示,IhDFR1和IhDFR2在蓝紫色花中随着花的发育表达量升高,在白色花中均低表达,IhFLS1在白色花中随着花的发育表达量升高,在蓝紫色花中均低表达,与RNA-seq结果保持一致。【结论】白色‘玉妃’中,IhDFR1和IhDFR2的低表达,及IhFLS1的高表达,使花色素苷积累受阻,部分代谢流由花色素苷转向黄酮醇,导致花色由蓝紫变为白色。【Objective】Flower color variation is of great significance for enriching color of ornamental plants,but it is difficult to clarify variation mechanism due to uncertainty of flower color variation.Dutch iris(Iris hollandica)is an important bulbous ornamental plant.In this study,the blue-purple wild type‘Zhanchi’and white mutant strain'Yufei'of Dutch iris were investigated to explore molecular mechanism and difference of pigment accumulation,so as to provide a basis for mechanism of flower color variation.【Method】In this study,using inner tepals of‘Zhanchi’and‘Yufei’from Dutch Iris as materials,UHPLC-QTOF-MS method was used to determine types and contents of anthocyanins and flavonols from two varieties of Dutch Iris,and the different expression genes related to anthocyanin synthesis were screened by transcriptome sequencing.Using different flowers in developmental stages of two varieties as materials,the different expression genes were verified by qRT-PCR.【Result】Results of metabolomics analysis revealed that delphinidin,cyanidin and its derivatives were accumulated in blue-purple flowers,which were almost no accumulation in white flowers, while the flavonol contents were increased in white ‘Yufei’. Results of RNA-seq analysis revealed that a total of 46 485 unigenes were obtained, and 27 073 unigenes of them were functionally annotated by public databases, accounting for 41.85% of the total. And 701 differentially expressed genes were obtained, 485 genes of which were up-regulated and 216 genes were down-regulated in white ‘Yufei’. Two dihydroflavonol-4-reductase genes and one flavonol synthase gene involving in anthocyanin biosynthetic pathway had different expression, named IhDFR1, IhDFR2 and IhFLS1. Down-regulated expression of IhDFR1 and IhDFR2 as well as up-regulated expression of IhFLS1 in white ‘Yufei’ led to significant decrease of anthocyanins and accumulation of flavonols, which caused metabolic flow from anthocyanin to flavonol. The qRT-PCR results of three genes sho

关 键 词：荷兰鸢尾 花色素苷 黄酮醇 转录组分析 二氢黄酮醇-4-还原酶基因 黄酮醇合成酶基因 

分 类 号：S682.19[农业科学—观赏园艺]