Journals
  Publication Years
  Keywords
Search within results Open Search
Please wait a minute...
For Selected: Toggle Thumbnails
Transcriptomic analysis reveals the transcription factors involved in regulating the expression of EPSPS gene, which confers glyphosate resistance of goosegrass (Eleusine indica)
ZHANG Chun, YU Chao-jie, ZHANG Tai-jie, GUO Wen-lei, TIAN Xing-shan
2021, 20 (8): 2180-2194.   DOI: 10.1016/S2095-3119(21)63682-1
Abstract169)      PDF in ScienceDirect      
Glyphosate inhibits the enzyme 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) and overexpression of the EPSPS gene is one of the molecular mechanisms conferring glyphosate resistance in weeds.  A regulatory sequence of EPSPS gene was isolated previously, and an alteration in its 5´-untranslated region (UTR) pyrimidine (Py)-rich stretch element is involved in the regulation of EPSPS expression in glyphosate-resistant (GR) Eleusine indica.  However, the transcription factors involved in this regulatory sequence remain to be elucidated.  In this study, we investigated the regulatory network of EPSPS overexpression associated genes in a GR E. indica population by RNA-seq.  The differentially expressed transcript analyses revealed that glyphosate treatment caused an increase in the expression of 2 752 unigenes and a decrease in the expression of 4 025 unigenes in the GR E. indica, compared to the glyphosate-susceptible (GS) E. indica.  Among them, 1 373 unigenes were identified to be co-expressed with the EPSPS gene in GR E. indica.  GO and KEGG pathway analyses showed that the up-regulated unigenes were mainly enriched in chloroplasts and associated with the shikimate biosynthesis pathway, chlorophy II and peroxisome metabolism processes.  Notably, the expression of a Shikimate kinase which catalyzed the conversion of Shikimate to Shikimate 3-phosphate (S3P, a substrate of EPSPS), was also up-regulated.  Eight transcription factors were identified as likely to be involved in the regulation of the EPSPS expression, and three of them (ARF2, ARF8 and BPC6) showed more binding sites because of a (CT)n insertion of the 5´-UTR Py-rich stretch element in GR.  However, the yeast one-hybrid assay illustrated that ARF8 and BPC6 could bind to the 5´-UTR Py-rich stretch element of wild type EPSPS, but could not bind to the mutated form.  Our data suggests that the transcriptional regulation of EPSPS expression is complex and was significantly altered in GR E. indica.  These discoveries provide new references for further study of the EPSPS overexpression mechanism that endows glyphosate resistance. 
Reference | Related Articles | Metrics
Use of chlorophyll fluorescence and P700 absorbance to rapidly detect glyphosate resistance in goosegrass (Eleusine indica)
ZHANG Tai-jie, FENG Li, TIAN Xing-shan, YANG Cai-hong, GAO Jia-dong
2015, 14 (4): 714-723.   DOI: 10.1016/S2095-3119(14)60869-8
Abstract1797)      PDF in ScienceDirect      
The rapid detection of glyphosate resistance in goosegrass (Eleusine indica) will enhance our ability to respond to new resistant populations of this major weed. Chlorophyll fluorescence (Fluo) and P700 (reaction center chlorophyll of photosystem I) absorbance were analyzed in one biotype of goosegrass that is resistant to glyphosate and in another that remains sensitive to the herbicide. Both biotypes were treated with a foliar spray of glyphosate. Differences in photosystem II maximum quantum yield (Fv/Fm), effective photochemical quantum yield (Y(II)), and non-photochemical quenching (NPQ) between the biotypes increased over time. Values for Fv/Fm and Y(II) differed between the two biotypes 24 h after treatment (HAT). Differentiated activities and energy dissipation processes of photosystem II (PSII) and energy dissipation processes of photosystem I (PSI) were manifested in the two biotypes 24 HAT with 20 mmol L–1 glyphosate. Differentiated energy dissipation processes of PSI were still apparent 24 HAT with 200 mmol L–1 glyphosate. These results indicate that the Fluo parameters related to PSII activity and energy dissipation and the P700 parameters related to energy dissipation are suitable indicators that enable rapid detection of glyphosate resistance in goosegrass.
Reference | Related Articles | Metrics