Understanding the metabolism of transgenic tomato plants in order to handle raw materials

INSANI, E.M.; PAZOS, A.A.; MIGNAQUI, A.C.; PIGHIN, D.G.; DOMINGUEZ, P.G.; ASIS, R.; KAMENETZKY, L.; CARRARI, F.

Zilina. Eslovaquia.

Conferencia; International Scientific Conference on Nutraceticals ans Functional Foods. Food and Function 2009.; 2009

The human genome project and ongoing research in post-genomic techniques have led to changes of paradigms in the life sciences. These are mainly responsible for a new level of understanding of biological systems and organisms as a whole. Recommendations of nutrient intakes were traditionally made on the basis of ensuring an adequate supply of nutrients to prevent deficiency disorders. However, the role of diet in preventing chronic diseases and improving quality of life is one of the major changes facing the concept of "personalized nutrition". In this way, it will be needed to adapt foods for specific nutritional requirements. The beginning includes having well-characterized raw materials to select the right choice. Regarding this issue, understanding the metabolism of the organs of the plants would enable implementation of the manipulation of genetic engineering to obtain raw materials of defined nutritional characteristics. The modification of the expression of endogenous genes through transgenesis is a way of studying the regulation of metabolism by means of reverse genetic. The family of transcription factors ASR (Abscisic acid -ABA-, Stress, Ripening) is distributed in higher plants. At present, four ASR factors (1-4) have been described in tomato plants. Its expression can be induced by abiotic stress, ABA, sucrose, as well as during the ripening process. Although a variety of genes are co-regulated by carbohydrates and ABA, the bases of these interactions are not still well known. The aim of this study is to functionally characterize ASR1 factor through metabolic analysis of transgenic tomato plants that over-express ASR1. When compared with wild type, biochemical analysis of the over expressing lines showed no significant differences in the content of hexoses -Glucose or Fructose- but showed increased values of aromatic amino acids -Tyr, Phe and Trp-, Cinamic acid derived phenolic compounds -Chlorogenic and Cumaric acid-, and flavonols -Miricetin and Quercetin-. These findings would suggest a stimulation of the Shikimic Acid and phenylpropanoids pathways, which in turn would support the hypothesis about the role of ASR1 protein in regulating carbon metabolism in organs of Solanaceae species. Therefore, it could be suggested the use of this protein in metabolic engineering in order to obtain raw materials focused on specific nutritional requirements.