以不同发育阶段款冬花(发育初期、中期、中后期、解封期及花朵期)为对象,基于核磁共振的代谢组学技术,分析其次生代谢物种类及含量的合成累积规律,并进行高通量转录组学测序,从差异表达的基因中寻找次生代谢物生物合成的关联酶基因。代谢组学分析发现,款冬花不同发育阶段的次生代谢物代谢组成明显不同,苯丙素类成分在发育初期至中后期含量较高,之后逐渐降低;黄酮类成分(芦丁、山奈酚)在发育的各个阶段含量均有波动,但总体变化不大。转录组学分析结果显示,与苯丙素类成分生物合成相关的酶基因(COMT、HCT),随着花蕾的发育表达量逐渐降低;与黄酮类成分合成相关的酶基因(FLS、F3H、DFR),其表达量在不同阶段变化不大。转录组测序中的相关酶基因表达量同次生代谢物成分的变化趋势基本一致。本文采用的代谢组学和转录组学结合的方式,对款冬花的次生代谢物累积规律进行分析,为今后款冬花次生代谢物的生物合成调控研究奠定了基础。
To investigate the types and accumulation of secondary metabolites,nuclear magnetic resonance based metabolic fingerprinting approach was used to analyze the flower bud(FL) of Tussilago farfara L.collected at different developmental stages:early stage,middle stage,later stage,jiefeng stage and flower stage.In addition,in order to search for genes related to the synthesis of secondary metabolites from differentially expressed genes,the global transcriptome of five different developing stages of FL were sequenced with high-throughput sequencing technology platform.The results of metabolism analysis showed that the metabolic composition of secondary metabolites in different developmental stageswere significantly different.The contents of phenylpropanoid were higher in the early stage of development,and then decreased gradually.The contents of flavonoids(rutin and kaempferol) were fluctuating in different periods,but their contents showed no significant difference among the five development stages.The results of the transcriptomics showed that the COMT and HCT were closely related to synthesis of phenyl-propanoids,and the expression of these genes decreased with the development of FL.The genes of the FLS,F3 H and DFR were related to the synthesis of flavonoids,and their expression levels had not changed much during the different developmental stages.The results of the transcriptomics were in agreement with the change of the chemical components revealed by the results of metabolism.In this study we explored the accumulation of secondary metabolites of FL from metabolic level and transcriptional level,and established the theoretical basis in biosynthesis regulation of secondary metabolites for FL.