title: In vitro culture may be the major contributing factor for transgenic versus nontransgenic proteomic plant differences.
abstract: Identification of differences between genetically modified plants and their original counterparts plays a central role in risk assessment strategy. Our main goal was to better understand the relevance of transgene presence, genetic, and epigenetic changes induced by transgene insertion, and in vitro culture in putative unintended differences between a transgenic and its comparator. Thus, we have used multiplex fluorescence 2DE coupled with MS to characterize the proteome of three different rice lines (Oryza sativa L. ssp. japonica cv. Nipponbare): a control conventional line (C), an Agrobacterium-transformed transgenic line (Ta) and a negative segregant (NSb). We observed that Ta and NSb appeared identical (with only one spot differentially abundant--fold difference ≥ 1.5), contrasting with the control (49 spots with fold difference ≥ 1.5, in both Ta and NSb vs. control). Given that in vitro culture was the only event in common between Ta and NSb, we hypothesize that in vitro culture stress was the most relevant condition contributing for the observed proteomic differences. MS protein identification support our hypothesis, indicating that Ta and NSb lines adjusted their metabolic pathways and altered the abundance of several stress related proteins in order to cope with in vitro culture.
authors.affiliation: National Health Institute, Lisboa, Portugal; Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Oeiras, Portugal.
authors.forename: Cátia
authors.initials: C
authors.lastname: Fonseca
authors.forename: Sébastien
authors.initials: S
authors.lastname: Planchon
authors.forename: Tânia
authors.initials: T
authors.lastname: Serra
authors.forename: Subhash
authors.initials: S
authors.lastname: Chander
authors.forename: Nelson J M
authors.initials: NJ
authors.lastname: Saibo
authors.forename: Jenny
authors.initials: J
authors.lastname: Renaut
authors.forename: M Margarida
authors.initials: MM
authors.lastname: Oliveira
authors.forename: Rita
authors.initials: R
authors.lastname: Batista
mesh_terms: D015180:Electrophoresis, Gel, Two-Dimensional; D018506:Gene Expression Regulation, Plant; D013058:Mass Spectrometry; D053858:Metabolic Networks and Pathways; D012275:Oryza / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D010788:Photosynthesis; D010940:Plant Proteins / Q000032:analysis / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D030821:Plants, Genetically Modified / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D040901:Proteomics; D013312:Stress, Physiological
chemical_list: D010940:Plant Proteins
keywords: Genetically modified foods safety assessment; In vitro culture; Multiplex fluorescence 2DE; Negative segregant; Plant proteomics