Project: FRuit Integrative Modelling

Commercial fruit production is under significant pressure from environmental stresses, but also by changes in the consumer?s demand for taste and nutritional value. One key goal of fruit biology is therefore to understand the factors that influence metabolite levels. Both genetic and environmental factors have a strong and multifaceted influence on fruit quality. They act and interact in such a complex way that it is extremely difficult to study their effects experimentally. To circumvent such difficulty, we will build a virtual tomato fruit that enables the prediction of metabolite levels given genetic and environmental inputs, by an iterative process between laboratories which combine expertise in fruit biology, ecophysiology, theoretical and experimental biochemistry, and biotechnology. There are three major aims: (1) To build a kinetic model encompassing the routes carbon takes, once imported into the fruit cells from the source organs of the mother plant. The model will include subcellular compartmentation. To parameterize the model, data for enzyme and transporter properties and metabolite levels will be measured in fruits harvested at different developmental stages and grown under contrasted environments. (2) To integrate the kinetic model with a phenomenological model predicting sugar and organic acid contents as functions of time, light intensity, temperature and water availability. Sub-models describing carbon and water transfer within the plant, fruit growth, sugar and organic acid accumulation will be implemented and integrated with the kinetic model. This ?multi-scale? integration will then be used to run virtual experiments. (3) To obtain large-scale experimental measures of the consequences of altered environmental conditions. Such studies will allow validation and iterative optimization of the model. As a first application of the combined model, environmental scenarios leading to metabolic phenotypes will be searched in silico for existing transgenic plants with altered enzyme activities, and validated.

Acronym	FRIM
Project Results (after finalisation)	Fruits, our major source of vitamins and anti-oxidants, represent a market of tens of billions of Euro per year. However, commercial fruit production is under significant pressure from environmental stresses, but also by changes in the consumer’s demand for taste and nutritional value. The possibility to anticipate such threats or opportunities would be of great help to breeders or producers. Thus, the Fruit Integrative Modelling (FRIM) consortium has initiated the construction of a suite of informatics models aiming at predicting fruit growth and quality as functions of both climatic scenarios and features encoded by the genome, in particular features of central metabolism that are responsible for sweetness and acidity. Experimental biologists and ecophysiologists from France (INRA and University of Bordeaux; INRA-Avignon) and Great Britain (Oxford University) have been growing hundreds of wild type and transgenic plants obtained from seeds produced in Germany (Max Planck Institute of Plant Molecular Physiology), to generate the data that modellers from Great Britain (Oxford Brookes University), France (INRA and University of Bordeaux; INRA-Avignon) and South Africa (Stellenbosch University) would use to develop, parameterise and validate their models of “virtual fruits”. Six models have been developed to deal with the various aspects of fruit development, from the plant bearing the fruits to the metabolic pathways producing sugars and acids. Virtual experiments can already be performed to deepen our knowledge about fruits, thus paving the way towards better fruits.
Network	ERASysBio+
Call	ERASysBio+-2008-01

Project partner

Number	Name	Role	Country
1	Institut National de la Recherche Agronomique	Coordinator	France
2	University of Bordeaux 2	Partner	France
3	Institut National de la Recherche Agronomique, Environment and Agronomy	Partner	France
4	University of Oxford	Partner	United Kingdom
5	Oxford Brookes University	Partner	United Kingdom
6	Max Planck Institute of Plant Molecular Physiology	Observer	Germany
7	University of Stellenbosch	Observer	South Africa