Functional characterization of target genes aiming VTE content improvement in Solanum Lycopersicum

• Grant number: 12/12531-8
• Support Opportunities: Regular Research Grants
• Start date: November 01, 2012
• End date: October 31, 2014
• Field of knowledge: Biological Sciences - Genetics - Molecular Genetics and Genetics of Microorganisms
• Principal Investigator: Maria Magdalena Rossi
• Grantee: Maria Magdalena Rossi
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant(s): 13/50481-5 - Unraveling the regulation of vitamin E metabolism in Solanum lycopersicum, AP.R

Abstract

Besides its economical and nutritional importance, tomato (Solanum lycopersicum) is a model system for plant physiology studies. The fresh fruit as well as the derivatives are sources of several antioxidants, including vitamin E (VTE). The understanding of the mechanisms involved in the biosynthesis, transport and accumulation of VTE in plants is highly desirable due its significant role in human health and plant physiology. In a previous study, based on an extensive tocopherol metabolic profile of S. pennellii introgressed lines, our group identified QTL associated with VTE content. An integrated analysis of metabolic, genomic and genetic data allowed us to propose 16 candidate loci probably involved in the observed tocopherol content alterations. These results constitute a comprehensive set of data to understand the natural variation of tomato VTE content. In this sense, the present project aims to evaluate the impact of some of the identified candidate genes in VTE biosynthesis and accumulation by performing a functional analysis. For each selected gene, three specific objectives were proposed: (i) to perform a transcriptional profile of wild and cultivated alleles and, evaluate the impact of the wild alleles' presence in the expression of all biosynthetic pathway genes; (ii) to determine the subcellular localization; finally, (iii) to analyze the effect of gene silencing on VTE content by VIGS (Virus Induced Gene Silencing). The results will provide new approaches for metabolism engineering in order to improve the nutritional value of this important crop. (AU)