title: Wounding tomato fruit elicits ripening-stage specific changes in gene expression and production of volatile compounds.
abstract: Fleshy fruits develop from an unripe organ that needs to be protected from damage to a ripe organ that attracts frugivores for seed dispersal through production of volatile organic compounds (VOCs). Thus, different responses to wounding damage are predicted. The aim of this study was to discover whether wound-induced changes in the transcriptome and VOC production alter as tomato transitions from unripe to ripe. Transcript changes were analysed 3h post-wounding using microarray analysis in two commercial salad-tomato (Solanum lycopersicum L.) cultivars: Luna Rossa and AVG, chosen for their high aroma production. This was followed by quantitative PCR on Luna Rossa genes involved in VOC biosynthesis and defence responses. VOCs elicited by wounding at different ripening stages were analysed by solid phase micro extraction and gas chromatography-mass spectrometry. Approximately 4000 differentially expressed genes were identified in the cultivar AVG and 2500 in Luna Rossa. In both cultivars the majority of genes were up-regulated and the most affected pathways were metabolism of terpenes, carotenoids, and lipids. Defence-related genes were mostly up-regulated in immature stages of development, whereas expression of genes related to VOCs changed at riper stages. More than 40 VOCs were detected and profiles changed with ripening stage. Thus, both transcriptome and VOC profiles elicited by wounding depend on stage of ripening, indicating a shift from defence to attraction.
authors.affiliation: Department of Agricultural and Environmental Sciences, Università degli Studi di Milano, Via Celoria 2, 20133 Milano, Italy School of Biosciences, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, UK.
authors.forename: Valentina
authors.initials: V
authors.lastname: Baldassarre
authors.affiliation: CRA-FLC Fodder and Dairy Productions Research Centre, Via A. Lombardo 11, 26900 Lodi, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Cabassi
authors.affiliation: School of Biosciences, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, UK.
authors.forename: Natasha D
authors.initials: ND
authors.lastname: Spadafora
authors.affiliation: Department of Biological and Environmental Sciences and Technologies, University of Salento, Provinciale Lecce-Monteroni, 73100 Lecce, Italy.
authors.forename: Alessio
authors.initials: A
authors.lastname: Aprile
authors.affiliation: School of Biosciences, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, UK.
authors.forename: Carsten T
authors.initials: CT
authors.lastname: Müller
authors.affiliation: School of Biosciences, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, UK rogershj@cf.ac.uk.
authors.forename: Hilary J
authors.initials: HJ
authors.lastname: Rogers
authors.affiliation: Department of Agricultural and Environmental Sciences, Università degli Studi di Milano, Via Celoria 2, 20133 Milano, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Ferrante
mesh_terms: D005638:Fruit / Q000737:chemistry / Q000254:growth & development* / Q000378:metabolism; D008401:Gas Chromatography-Mass Spectrometry; D018506:Gene Expression Regulation, Plant; D018551:Solanum lycopersicum / Q000737:chemistry / Q000254:growth & development* / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D055549:Volatile Organic Compounds / Q000737:chemistry / Q000378:metabolism*
chemical_list: D010940:Plant Proteins; D055549:Volatile Organic Compounds
keywords: Microarrays; Solanum lycopersicum; VOCs; molecular markers; ripening; wounding.