title: Salt and genotype impact on plant physiology and root proteome variations in tomato.
abstract: To evaluate the genotypic variation of salt stress response in tomato, physiological analyses and a proteomic approach have been conducted in parallel on four contrasting tomato genotypes. After a 14 d period of salt stress in hydroponic conditions, the genotypes exhibited different responses in terms of plant growth, particularly root growth, foliar accumulation of Na(+), and foliar K/Na ratio. As a whole, Levovil appeared to be the most tolerant genotype while Cervil was the most sensitive one. Roma and Supermarmande exhibited intermediary behaviours. Among the 1300 protein spots reproducibly detected by two-dimensional electrophoresis, 90 exhibited significant abundance variations between samples and were submitted to mass spectrometry for identification. A common set of proteins (nine spots), up- or down-regulated by salt-stress whatever the genotype, was detected. But the impact of the tomato genotype on the proteome variations was much higher than the salt effect: 33 spots that were not variable with salt stress varied with the genotype. The remaining number of variable spots (48) exhibited combined effects of the genotype and the salt factors, putatively linked to the degrees of genotype tolerance. The carbon metabolism and energy-related proteins were mainly up-regulated by salt stress and exhibited most-tolerant versus most-sensitive abundance variations. Unexpectedly, some antioxidant and defence proteins were also down-regulated, while some proteins putatively involved in osmoprotectant synthesis and cell wall reinforcement were up-regulated by salt stress mainly in tolerant genotypes. The results showed the effect of 14 d stress on the tomato root proteome and underlined significant genotype differences, suggesting the importance of making use of genetic variability.
authors.affiliation: Unité d'Ecophysiologie et Nutrition des Plantes, Département de Biologie, Faculté des Sciences de Tunis, Université Tunis El Manar, 1060 Tunisie.
authors.forename: Arafet
authors.initials: A
authors.lastname: Manaa
authors.forename: Hela
authors.initials: H
authors.lastname: Ben Ahmed
authors.forename: Benoît
authors.initials: B
authors.lastname: Valot
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Bouchet
authors.forename: Samira
authors.initials: S
authors.lastname: Aschi-Smiti
authors.forename: Mathilde
authors.initials: M
authors.lastname: Causse
authors.forename: Mireille
authors.initials: M
authors.lastname: Faurobert
mesh_terms: D000222:Adaptation, Physiological / Q000187:drug effects / Q000235:genetics; D000975:Antioxidants / Q000378:metabolism; D002244:Carbon / Q000378:metabolism; D002473:Cell Wall / Q000187:drug effects / Q000378:metabolism; D002712:Chlorides / Q000378:metabolism; D002853:Chromatography, Liquid; D015536:Down-Regulation / Q000187:drug effects / Q000235:genetics; D015180:Electrophoresis, Gel, Two-Dimensional; D004734:Energy Metabolism / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D014644:Genetic Variation / Q000187:drug effects; D005838:Genotype; D018551:Solanum lycopersicum / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development / Q000502:physiology*; D013058:Mass Spectrometry; D008565:Membrane Proteins / Q000378:metabolism; D009995:Osmosis / Q000187:drug effects; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000378:metabolism*; D020543:Proteome / Q000378:metabolism*; D054712:Salinity; D055049:Salt Tolerance / Q000187:drug effects / Q000235:genetics; D012964:Sodium / Q000378:metabolism; D012965:Sodium Chloride / Q000494:pharmacology*; D013312:Stress, Physiological / Q000187:drug effects / Q000235:genetics; D014157:Transcription Factors / Q000378:metabolism; D015854:Up-Regulation / Q000187:drug effects / Q000235:genetics
chemical_list: D000975:Antioxidants; D002712:Chlorides; D008565:Membrane Proteins; D010940:Plant Proteins; D020543:Proteome; D014157:Transcription Factors; D012965:Sodium Chloride; D002244:Carbon; D012964:Sodium