title: A composite transcriptional signature differentiates responses towards closely related herbicides in Arabidopsis thaliana and Brassica napus.
abstract: In this study, genome-wide expression profiling based on Affymetrix ATH1 arrays was used to identify discriminating responses of Arabidopsis thaliana to five herbicides, which contain active ingredients targeting two different branches of amino acid biosynthesis. One herbicide contained glyphosate, which targets 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), while the other four herbicides contain different acetolactate synthase (ALS) inhibiting compounds. In contrast to the herbicide containing glyphosate, which affected only a few transcripts, many effects of the ALS inhibiting herbicides were revealed based on transcriptional changes related to ribosome biogenesis and translation, secondary metabolism, cell wall modification and growth. The expression pattern of a set of 101 genes provided a specific, composite signature that was distinct from other major stress responses and differentiated among herbicides targeting the same enzyme (ALS) or containing the same chemical class of active ingredient (sulfonylurea). A set of homologous genes could be identified in Brassica napus that exhibited a similar expression pattern and correctly distinguished exposure to the five herbicides. Our results show the ability of a limited number of genes to classify and differentiate responses to closely related herbicides in A. thaliana and B. napus and the transferability of a complex transcriptional signature across species.
authors.affiliation: National Health and Environmental Effects Research Laboratory, Western Ecology Division, U.S. Environmental Protection Agency, Office of Research and Development, Corvallis, OR 97333, USA.
authors.forename: Malay
authors.initials: M
authors.lastname: Das
authors.forename: Jay R
authors.initials: JR
authors.lastname: Reichman
authors.forename: Georg
authors.initials: G
authors.lastname: Haberer
authors.forename: Gerhard
authors.initials: G
authors.lastname: Welzl
authors.forename: Felipe F
authors.initials: FF
authors.lastname: Aceituno
authors.forename: Michael T
authors.initials: MT
authors.lastname: Mader
authors.forename: Lidia S
authors.initials: LS
authors.lastname: Watrud
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Pfleeger
authors.forename: Rodrigo A
authors.initials: RA
authors.lastname: Gutiérrez
authors.forename: Anton R
authors.initials: AR
authors.lastname: Schäffner
authors.forename: David M
authors.initials: DM
authors.lastname: Olszyk
mesh_terms: D051229:3-Phosphoshikimate 1-Carboxyvinyltransferase / Q000037:antagonists & inhibitors; D000095:Acetolactate Synthase / Q000037:antagonists & inhibitors; D000596:Amino Acids / Q000096:biosynthesis; D017360:Arabidopsis / Q000187:drug effects* / Q000235:genetics* / Q000378:metabolism; D029688:Brassica napus / Q000187:drug effects* / Q000235:genetics* / Q000378:metabolism; D020869:Gene Expression Profiling; D017343:Genes, Plant / Q000187:drug effects; D006540:Herbicides / Q000494:pharmacology*; D013045:Species Specificity
chemical_list: D000596:Amino Acids; D006540:Herbicides; D000095:Acetolactate Synthase; D051229:3-Phosphoshikimate 1-Carboxyvinyltransferase