Investigating the mechanisms of glyphosate resistance in goosegrass (Eleusine indica (L.) Gaertn.) by RNA sequencing technology. (30th January 2017)

• Record Type: Journal Article
• Authors: Chen, Jingchao; Huang, Hongjuan; Wei, Shouhui; Huang, Zhaofeng; Wang, Xu; Zhang, Chaoxian
• Is Part Of: Plant journal. Volume 89:Number 2(2017)
• Page Start: 407
• Page End: 415
• Publication Date: 2017-01-30
• Subjects: transcriptomics -- next‐generation sequencing -- herbicide resistance -- glyphosate -- (Eleusine indica (L.) Gaertn.); Plant molecular biology -- Periodicals; Plant cells and tissues -- Periodicals; Botany -- Periodicals; 580
• DOI: 10.1111/tpj.13395
• Languages: English
• ISSNs: 0960-7412

Abstract

Summary: Glyphosate is an important non‐selective herbicide that is in common use worldwide. However, evolved glyphosate‐resistant (GR) weeds significantly affect crop yields. Unfortunately, the mechanisms underlying resistance in GR weeds, such as goosegrass ( Eleusine indica (L.) Gaertn.), an annual weed found worldwide, have not been fully elucidated. In this study, transcriptome analysis was conducted to further assess the potential mechanisms of glyphosate resistance in goosegrass. The RNA sequencing libraries generated 24 597 462 clean reads. De novo assembly analysis produced 48 852 UniGenes with an average length of 847 bp. All UniGenes were annotated using seven databases. Sixteen candidate differentially expressed genes selected by digital gene expression analysis were validated by quantitative real‐time PCR (qRT‐PCR). Among these UniGenes, the EPSPS and PFK genes were constitutively up‐regulated in resistant (R) individuals and showed a higher copy number than that in susceptible (S) individuals. The expressions of four UniGenes relevant to photosynthesis were inhibited by glyphosate in S individuals, and this toxic response was confirmed by gas exchange analysis. Two UniGenes annotated as glutathione transferase (GST) were constitutively up‐regulated in R individuals, and were induced by glyphosate both in R and S. In addition, the GST activities in R individuals were higher than in S. Our research confirmed that two UniGenes ( PFK, EPSPS ) were strongly associated with target resistance, and two GST‐annotated UniGenes may play a role in metabolic glyphosate resistance in goosegrass. Significance Statement: Glyphosate‐resistant weeds affect crop yields. Here we used RNA‐seq to explore mechanisms of resistance in glyphosate‐resistant populations of goosegrass. In addition to the expected target of glyphosate, EPSP synthase, increased expression of phosphofructokinase and of glutathione S‐ transferases were strongly associated with glyphosate resistance, suggesting that they might play a role in metabolic resistance.