Fruit quality and gene expresssion
Authors: Fabien Mounet, Annick Moing, Virginie Garcia, Johann Petit, Michael Maucourt, Catherine Deborde, Stéphane Bernillon, Gwenaëlle Le Gall, Ian Colquhoun, Marianne Defernez, Jean-Luc Giraudel, Dominique Rolin, Christophe Rothan, and Martine Lemaire-Chamle
Relevance of the research
The quality of tomato fruits depends on the compounds at maturity. The study of changes in the expression and cross-interactions between genes involved in the biosynthesis of these compounds can provide us with information about genes that are potentially crucial for the setting of tomato fruit quality.
In tomato, the acquisition of fruit juiciness, also called fleshy fruit trait, takes place during growth of the green fruit. It involves the formation of large cells that accumulate water, sugars, organic acids and other compounds, all key determinants of fruit texture and taste. This process takes place in two major tissues: the fruit wall and the jelly surrounding the seeds.
We did a microscopic analysis of fruit wall tissue and the jelly surrounding the seed and statistical analysis of the fruit compound contents. Fruit composition of the two tissues was combined with analysis of gene expression .
The microscopic analysis showed that the fruit wall tissue and the jelly surrounding the seeds differ in terms of cell size, structure, and growth rate. Statistical analyses of the fruit compound contents showed that the two tissues differ in their composition for some compounds including sugar and organic acids, but present parallel changes for some other compounds during fruit growth.
The combined analysis of gene expression and fruit composition of the two tissues revealed that several changes in compound contents are explained by changes in expression of the genes involved in their biosynthesis. It also highlighted numerous cross-interactions between genes involved in regulatory processes. Some of these genes, that seemed to be crossroads, will be further studied
Fabien Mounet, Annick Moing, Virginie Garcia, Johann Petit, Michael Maucourt, Catherine Deborde, Stéphane Bernillon, Gwenaëlle Le Gall, Ian Colquhoun, Marianne Defernez, Jean-Luc Giraudel, Dominique Rolin, Christophe Rothan, and Martine Lemaire-Chamle (2009). Gene and Metabolite Regulatory Network Analysis of Early Developing Fruit Tissues Highlights New Candidate Genes for the Control of Tomato Fruit Composition and Development. Plant Physiology, March 2009, Vol. 149, pp. 1505–1528