title: Transient silencing of CHALCONE SYNTHASE during fruit ripening modifies tomato epidermal cells and cuticle properties.
abstract: Tomato (Solanum lycopersicum) fruit ripening is accompanied by an increase in CHALCONE SYNTHASE (CHS) activity and flavonoid biosynthesis. Flavonoids accumulate in the cuticle, giving its characteristic orange color that contributes to the eventual red color of the ripe fruit. Using virus-induced gene silencing in fruits, we have down-regulated the expression of SlCHS during ripening and compared the cuticles derived from silenced and nonsilenced regions. Silenced regions showed a pink color due to the lack of flavonoids incorporated to the cuticle. This change in color was accompanied by several other changes in the cuticle and epidermis. The epidermal cells displayed a decreased tangential cell width; a decrease in the amount of cuticle and its main components, cutin and polysaccharides, was also observed. Flavonoids dramatically altered the cuticle biomechanical properties by stiffening the elastic and viscoelastic phase and by reducing the ability of the cuticle to deform. There seemed to be a negative relation between SlCHS expression and wax accumulation during ripening that could be related to the decreased cuticle permeability to water observed in the regions silencing SlCHS. A reduction in the overall number of ester linkages present in the cutin matrix was also dependent on the presence of flavonoids.
authors.affiliation: Instituto de Hortofruticultura Subtropical y Mediterránea La Mayora, Universidad de Málaga-Consejo Superior de Investigaciones Científicas (L.E., J.J.R.-P., R.F.-M., A.H., E.D.), and Departamento de Biología Molecular y Bioquímica (L.E., A.H.), Universidad de Málaga, E-29071 Malaga, Spain;Departamento de Mejora Genética y Biotecnología, Estación Experimental La Mayora, Algarrobo-Costa, E-29750 Malaga, Spain (J.J.R.-P., R.F.-M., E.D.); andNanophysics, Istituto Italiano di Tecnologia, 16163 Genoa, Italy (J.A.H.-G.).
authors.forename: Laura
authors.initials: L
authors.lastname: España
authors.affiliation: Instituto de Hortofruticultura Subtropical y Mediterránea La Mayora, Universidad de Málaga-Consejo Superior de Investigaciones Científicas (L.E., J.J.R.-P., R.F.-M., A.H., E.D.), and Departamento de Biología Molecular y Bioquímica (L.E., A.H.), Universidad de Málaga, E-29071 Malaga, Spain;Departamento de Mejora Genética y Biotecnología, Estación Experimental La Mayora, Algarrobo-Costa, E-29750 Malaga, Spain (J.J.R.-P., R.F.-M., E.D.); andNanophysics, Istituto Italiano di Tecnologia, 16163 Genoa, Italy (J.A.H.-G.).
authors.forename: José A
authors.initials: JA
authors.lastname: Heredia-Guerrero
authors.affiliation: Instituto de Hortofruticultura Subtropical y Mediterránea La Mayora, Universidad de Málaga-Consejo Superior de Investigaciones Científicas (L.E., J.J.R.-P., R.F.-M., A.H., E.D.), and Departamento de Biología Molecular y Bioquímica (L.E., A.H.), Universidad de Málaga, E-29071 Malaga, Spain;Departamento de Mejora Genética y Biotecnología, Estación Experimental La Mayora, Algarrobo-Costa, E-29750 Malaga, Spain (J.J.R.-P., R.F.-M., E.D.); andNanophysics, Istituto Italiano di Tecnologia, 16163 Genoa, Italy (J.A.H.-G.).
authors.forename: José J
authors.initials: JJ
authors.lastname: Reina-Pinto
authors.affiliation: Instituto de Hortofruticultura Subtropical y Mediterránea La Mayora, Universidad de Málaga-Consejo Superior de Investigaciones Científicas (L.E., J.J.R.-P., R.F.-M., A.H., E.D.), and Departamento de Biología Molecular y Bioquímica (L.E., A.H.), Universidad de Málaga, E-29071 Malaga, Spain;Departamento de Mejora Genética y Biotecnología, Estación Experimental La Mayora, Algarrobo-Costa, E-29750 Malaga, Spain (J.J.R.-P., R.F.-M., E.D.); andNanophysics, Istituto Italiano di Tecnologia, 16163 Genoa, Italy (J.A.H.-G.).
authors.forename: Rafael
authors.initials: R
authors.lastname: Fernández-Muñoz
authors.affiliation: Instituto de Hortofruticultura Subtropical y Mediterránea La Mayora, Universidad de Málaga-Consejo Superior de Investigaciones Científicas (L.E., J.J.R.-P., R.F.-M., A.H., E.D.), and Departamento de Biología Molecular y Bioquímica (L.E., A.H.), Universidad de Málaga, E-29071 Malaga, Spain;Departamento de Mejora Genética y Biotecnología, Estación Experimental La Mayora, Algarrobo-Costa, E-29750 Malaga, Spain (J.J.R.-P., R.F.-M., E.D.); andNanophysics, Istituto Italiano di Tecnologia, 16163 Genoa, Italy (J.A.H.-G.).
authors.forename: Antonio
authors.initials: A
authors.lastname: Heredia
authors.affiliation: Instituto de Hortofruticultura Subtropical y Mediterránea La Mayora, Universidad de Málaga-Consejo Superior de Investigaciones Científicas (L.E., J.J.R.-P., R.F.-M., A.H., E.D.), and Departamento de Biología Molecular y Bioquímica (L.E., A.H.), Universidad de Málaga, E-29071 Malaga, Spain;Departamento de Mejora Genética y Biotecnología, Estación Experimental La Mayora, Algarrobo-Costa, E-29750 Malaga, Spain (J.J.R.-P., R.F.-M., E.D.); andNanophysics, Istituto Italiano di Tecnologia, 16163 Genoa, Italy (J.A.H.-G.) edominguez@eelm.csic.es.
authors.forename: Eva
authors.initials: E
authors.lastname: Domínguez
mesh_terms: D000217:Acyltransferases / Q000235:genetics* / Q000378:metabolism; D005419:Flavonoids / Q000378:metabolism; D005638:Fruit / Q000166:cytology / Q000502:physiology; D018506:Gene Expression Regulation, Plant; D020868:Gene Silencing; D018551:Solanum lycopersicum / Q000502:physiology*; D019441:Plant Epidermis / Q000166:cytology*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D017550:Spectroscopy, Fourier Transform Infrared; D014885:Waxes / Q000737:chemistry
chemical_list: D005419:Flavonoids; D010940:Plant Proteins; D014885:Waxes; D000217:Acyltransferases; C020141:flavanone synthetase