苦茶碱代谢关键转录因子基因的筛选鉴定

摘要/Abstract

摘要： 苦茶是我国特异的茶树资源,主要分布于西南地区,富含苦茶碱（1,3,7,9-四甲基尿酸）。苦茶碱具有镇静、催眠和抗抑郁等多种生理活性,其合成关键基因（苦茶碱合成酶基因）已经得到克隆和研究,但是苦茶碱代谢调控机制的研究鲜有报道。为了挖掘与苦茶碱代谢调控相关的转录因子,本研究以高苦茶碱（GKC）、低苦茶碱（LKC）茶树品种以及常规茶树品种（YK10）为研究对象,通过HPLC和RNA-seq分别就样品的嘌呤生物碱含量和基因表达情况进行分析,并通过荧光定量PCR验证了转录组数据的可靠性。结果表明,GKC和LKC的苦茶碱含量分别为21.82 mg·g^-1和14.70 mg·g^-1,而YK10中检测不到苦茶碱,另外,GKC和LKC的咖啡碱含量均低于15.00 mg·g^-1;通过RNA-seq方法,获得了3 948个GKC vs YK10和LKC vs YK10共同的且表达趋势一致的差异基因,这些差异基因是分属29个家族的96个转录因子,通过分析最终确定30个候选转录因子,尤其是属于NAC和HD-ZIP转录因子家族的CSS0012182、CSS0013789、CSS0041233、novel.16084和CSS0014547等转录因子可能是参与苦茶碱代谢调控的关键基因。

关键词: 苦茶, 苦茶碱, RNA测序, 转录因子

Abstract: Kucha is a unique tea resource rich in theacrine (1,3,7,9-tetramethyluric acid) in southwest China. Theacrine has a variety of physiological activities such as sedation, hypnosis and antidepressant. Theacrine synthesis enzyme, the key gene for theacrine biosynthesis, had been cloned and studied. However, there were few reports on the regulation mechanism of theacrine metabolism. In order to obtain the transcription factors related to theacrine metabolism, kucha (GKC and LKC) and normal tea cultivar (YK10) were used as research materials. Purine alkaloid content and related gene expressions in the samples were detected by HPLC and RNA-seq, respectively. And the reliability of the transcriptome data were verified by quantitative real-time PCR (qRT-PCR). The results show that the contents of theacrine in GKC and LKC were 21.82 mg·g^-1 and 14.70 mg·g^-1, respectively, while the content of theacrine in YK10 was not detected. In addition, the caffeine contents of GKC and LKC were both lower than 15.00 mg·g^-1. Based on RNA-seq, 3 948 differentially expressed genes (DEGs) had the consistent expression trends in GKC vs YK10 and LKC vs YK10. These DEGs included 96 transcription factors belonging to 29 families. Among them, 30 candidate transcription factors might be the key genes involved in the regulation of theacrine metabolism, especially NAC and HD-ZIP family transcription factors such as CSS0012182, CSS0013789, CSS0041233, novel.16084 and CSS0014547.

Key words: Kucha, theacrine, RNA-seq, transcription factor

中图分类号:

S571.1

刘玉飞, 庞丹丹, 李友勇, 蒋会兵, 田易萍, 孙云南, 陈林波. 苦茶碱代谢关键转录因子基因的筛选鉴定[J]. 茶叶科学, 2022, 42(1): 41-50.

LIU Yufei, PANG Dandan, LI Youyong, JIANG Huibing, TIAN Yiping, SUN Yunnan, CHEN Linbo. The Screening and Identification of Key Transcription Factor Genes for Theacrine Metabolism[J]. Journal of Tea Science, 2022, 42(1): 41-50.

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