中国农业科学

• • 上一篇    

基于WGCNA鉴定茶树响应草甘膦相关的共表达基因

郭永春1,王鹏杰1,金珊1,侯炳豪1,王淑燕1,赵峰2,叶乃兴1   

  1. 1福建农林大学园艺学院/茶学福建省高校重点实验室,福州350002;2福建中医药大学药学院,福州350122
  • 发布日期:2021-07-07

Identification of Co-expression Gene Related to Tea Plant Response to Glyphosate Based on WGCNA

GUO YongChun1, WANG PengJie1, JIN Shan1, WANG ShuYan1, ZHAO Feng2, YE NaiXing1   

  1. 1College of Horticulture, Fujian Agriculture and Forestry University/Key Laboratory of Tea Science in Universities of Fujian province, Fuzhou 350002; 2School of Pharmacy, Fujian University of Chinese Medicine, Fuzhou 350122
  • Online:2021-07-07

摘要: 【目的】分析茶树响应草甘膦相关的基因表达规律和调控途径,在转录水平上探究草甘膦对茶树的作用,确定茶树响应草甘膦的关键基因。【方法】以茶树品种金观音为试验材料,将推荐使用浓度的草甘膦施于茶树土壤基质表面,经0、0.25、1、3和7 d后,取叶片进行转录组测序,并测定莽草酸含量。利用WGCNA方法联合分析转录组和莽草酸含量数据,鉴定与草甘膦响应相关的共表达基因模块,筛选关键调控基因。【结果】茶树叶片中的莽草酸含量在草甘膦处理后的0.25、1和3 d降低,而在7 d时大量积累(为对照的6.99倍)。从表达谱数据中筛选得到12 568个差异表达基因(DEGs),草甘膦处理不同时间点与未处理数据比对的DEGs均显著富集在苯丙烷、类黄酮生物合成及植物激素信号转导途径,此外,草甘膦处理分别诱导茶树莽草酸代谢及其下游苯丙烷、类黄酮生物合成和激素信号转导途径相关的24、52、31和69个基因差异表达。通过加权基因共表达网络(WGCNA)方法鉴定得到19个基因模块,将转录组与莽草酸含量数据相关联,筛选到两个与草甘膦响应高度相关的关键基因模块,分别包含2 024和2 305个基因。选取关键模块中连通度最高的前50个基因进行共表达分析,获得6个关键调控基因,包括2个抗性基因(SHMT和RPM)、1个耐药性基因(PDR)、1个离子转运基因(At)、1个膜转运基因(GPT)和1个转录因子(ERF)。【结论】草甘膦通过干扰茶树叶片中莽草酸代谢,影响其下游代谢途径苯丙烷、类黄酮生物合成及激素信号转导途径的基因转录。此外,研究还鉴定到2个草甘膦响应密切相关的共表达模块,发现SHMT、RPM、At、PDR、ERF和GPT等多个潜在候选基因和转录因子在茶树抵御草甘膦逆境中发挥重要作用。


关键词: 茶树, 草甘膦, 莽草酸, 转录组学, WGCNA

Abstract: 【Objective】This study aims at analysing both expression patterns and regulatory pathways of tea plants in response to glyphosate stressing, through which could revealed the effect of glyphosate herbicides on tea plants at transcriptional level and identify key genes of tea plants.【Method】C. sinensis cv ‘Jin-guanyin’ was applied as material plant. A recommended concentration of glyphosate was irrigated to test plants.Samples were collected at different time intervals (0, 0.25, 1, 3 and 7 d). The samples were sequenced by transcriptome, the content of shikimic acid was also quantified.The WGCNA method was used to jointly analyze transcriptome and shikimic acid content data, identify co-expressed gene modules related to glyphosate response, and screen out key regulatory genes.【Results】the content of shikimic acid in tea leaves reduced gradually during first 3 days. However, it suddenly reached a peak on the 7th day( 6.99 times compared to no glyphosate treated sample).A total of 12568 differential expression genes (DEGs) were also identified,whichmainly enriched in phenylpropane, flavonoid biosynthesis and plant hormone signal transduction pathways. In addition, glyphosate treatment induced 24, 52, 31 and 69 genes respectively which related to shikimic acid metabolism, phenylpropane, flavonoid biosynthesis and hormone signal transduction pathways. A total of 19 modules were screened out by WGCNA method. Correlate analysis of transcriptome and shikimic acid content indicated two key modules which including 2024 and 2305 genes, respectively. The top 50 genes with the highest connectivity in the key modules were selected for co-expression analysis, and 6 key response genes were obtained, including 2 resistance genes (SHMTandRPM), 1 drug resistance gene (PDR), 1 ion transport gene (At), 1 membrane transport gene (GPT) and 1 transcription factor gene (ERF). 【Conclusion】Glyphosate could affect downstream genes transcription of phenylpropane, flavonoid biosynthesis and hormone signal transduction pathways by interfering shikimic acid metabolism of tea plants.In addition, the study also identified two co-expression modules closely related to glyphosate response, and found that multiple potential candidate genes and transcription factors can resist glyphosate stress, such asSHMT, RPM, At, PDR, ERFandGPT.

Key words: Camellia sinensis, glyphosate, Shikimic acid, transcriptome, WGCNA