Genetic dissection of vitamin E biosynthesis in tomato

Vegetables are critical for human health as they are a source of multiple vitamins including vitamin E (VTE). In plants, the synthesis of VTE compounds, tocopherol and tocotrienol, derives from precursors of the shikimate and methylerythritol phosphate pathways. Quantitative trait loci (QTL) for α-tocopherol content in ripe fruit have previously been determined in an Solanum pennellii tomato introgression line population. In this work, variations of tocopherol isoforms (α, β, γ, and δ) in ripe fruits of these lines were studied. In parallel all tomato genes structurally associated with VTE biosynthesis were identified and mapped. Previously identified VTE QTL on chromosomes 6 and 9 were confirmed whilst novel ones were identified on chromosomes 7 and 8. Integrated analysis at the metabolic, genetic and genomic levels allowed us to propose 16 candidate loci putatively affecting tocopherol content in tomato. A comparative analysis revealed polymorphisms at nucleotide and amino acid levels between Solanum lycopersicum and S. pennellii candidate alleles. Moreover, evolutionary analyses showed the presence of codons evolving under both neutral and positive selection, which may explain the phenotypic differences between species. These data represent an important step in understanding the genetic determinants of VTE natural variation in tomato fruit and as such in the ability to improve the content of this important nutriceutical.

Instituto de Biotecnología

Fil: Almeida de Souza, Juliana Beatriz. Universidade de Sao Paulo. Instituto de Biociências. Departamento de Botânica; Brasil

Fil: Quadrana, Leandro Daniel. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Fil: Asis, Ramón. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas; Argentina

Fil: Setta, Nathalia. Universidade de Sao Paulo. Instituto de Biociências. Departamento de Botânica; Brasil

Fil: Godoy, Fabiana de. Universidade de Sao Paulo. Instituto de Biociências. Departamento de Botânica; Brasil

Fil: Bermúdez, Luisa. Universidade de Sao Paulo. Instituto de Biociências. Departamento de Botânica; Brasil

Fil: Otaiza, Santiago N. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Centro de Investigaciones en Bioquímica Clínica e Inmunología; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas; Argentina

Fil: Silva, Junia V. Corrêa da. Universidade de Sao Paulo. Instituto de Biociências. Departamento de Botânica; Brasil

Fil: Fernie, Alisdair R. Max Planck Institute for Molecular Plant Physiology; Alemania

Fil: Carrari, Fernando Oscar. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.

Fil: Rossi, Magdalena. Universidade de São Pablo. Instituto de Biociências. Departamento de Botânica; Brasil