title: Molecular responses of genetically modified maize to abiotic stresses as determined through proteomic and metabolomic analyses.
abstract: Some genetically modified (GM) plants have transgenes that confer tolerance to abiotic stressors. Meanwhile, other transgenes may interact with abiotic stressors, causing pleiotropic effects that will affect the plant physiology. Thus, physiological alteration might have an impact on the product safety. However, routine risk assessment (RA) analyses do not evaluate the response of GM plants exposed to different environmental conditions. Therefore, we here present a proteome profile of herbicide-tolerant maize, including the levels of phytohormones and related compounds, compared to its near-isogenic non-GM variety under drought and herbicide stresses. Twenty differentially abundant proteins were detected between GM and non-GM hybrids under different water deficiency conditions and herbicide sprays. Pathway enrichment analysis showed that most of these proteins are assigned to energetic/carbohydrate metabolic processes. Among phytohormones and related compounds, different levels of ABA, CA, JA, MeJA and SA were detected in the maize varieties and stress conditions analysed. In pathway and proteome analyses, environment was found to be the major source of variation followed by the genetic transformation factor. Nonetheless, differences were detected in the levels of JA, MeJA and CA and in the abundance of 11 proteins when comparing the GM plant and its non-GM near-isogenic variety under the same environmental conditions. Thus, these findings do support molecular studies in GM plants Risk Assessment analyses.
authors.affiliation: Department of Crop Science, Federal University of Santa Catarina, Florianópolis, Brazil.|Genøk Center for Biosafety, Tromsø, Norway.|Department of Engineering & Natural Sciences, Western Norway University of Applied Siences, Sogndal, Norway.
authors.forename: Rafael Fonseca
authors.initials: RF
authors.lastname: Benevenuto
authors.affiliation: Genøk Center for Biosafety, Tromsø, Norway.
authors.forename: Sarah Zanon
authors.initials: SZ
authors.lastname: Agapito-Tenfen
authors.affiliation: Department of Crop Science, Federal University of Santa Catarina, Florianópolis, Brazil.
authors.forename: Vinicius
authors.initials: V
authors.lastname: Vilperte
authors.affiliation: Genøk Center for Biosafety, Tromsø, Norway.|Unit for Environmental Science and Management, North-West University, Potchefstroom, South Africa.
authors.forename: Odd-Gunnar
authors.initials: OG
authors.lastname: Wikmark
authors.affiliation: Human Metabolomics, North-West University, Potchefstroom, South Africa.
authors.forename: Peet Jansen
authors.initials: PJ
authors.lastname: van Rensburg
authors.affiliation: Department of Crop Science, Federal University of Santa Catarina, Florianópolis, Brazil.
authors.forename: Rubens Onofre
authors.initials: RO
authors.lastname: Nodari
mesh_terms: D002853:Chromatography, Liquid; D055864:Droughts; D055432:Metabolomics / Q000379:methods; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism*; D040901:Proteomics / Q000379:methods*; D053719:Tandem Mass Spectrometry; D003313:Zea mays / Q000235:genetics / Q000378:metabolism*