Malate Plays a Crucial Role in Starch Metabolism, Ripening, and Soluble Solid Content of Tomato Fruit and Affects Postharvest Softening
Open Access
- 31 December 2010
- journal article
- research article
- Published by Oxford University Press (OUP) in Plant Cell
- Vol. 23 (1), 162-184
- https://doi.org/10.1105/tpc.109.072231
Abstract
Despite the fact that the organic acid content of a fruit is regarded as one of its most commercially important quality traits when assessed by the consumer, relatively little is known concerning the physiological importance of organic acid metabolism for the fruit itself. Here, we evaluate the effect of modifying malate metabolism in a fruit-specific manner, by reduction of the activities of either mitochondrial malate dehydrogenase or fumarase, via targeted antisense approaches in tomato (Solanum lycopersicum). While these genetic perturbations had relatively little effect on the total fruit yield, they had dramatic consequences for fruit metabolism, as well as unanticipated changes in postharvest shelf life and susceptibility to bacterial infection. Detailed characterization suggested that the rate of ripening was essentially unaltered but that lines containing higher malate were characterized by lower levels of transitory starch and a lower soluble sugars content at harvest, whereas those with lower malate contained higher levels of these carbohydrates. Analysis of the activation state of ADP-glucose pyrophosphorylase revealed that it correlated with the accumulation of transitory starch. Taken together with the altered activation state of the plastidial malate dehydrogenase and the modified pigment biosynthesis of the transgenic lines, these results suggest that the phenotypes are due to an altered cellular redox status. The combined data reveal the importance of malate metabolism in tomato fruit metabolism and development and confirm the importance of transitory starch in the determination of agronomic yield in this species.Keywords
This publication has 129 references indexed in Scilit:
- NTRC links built-in thioredoxin to light and sucrose in regulating starch synthesis in chloroplasts and amyloplastsProceedings of the National Academy of Sciences of the United States of America, 2009
- RNA Interference of LIN5 in Tomato Confirms Its Role in Controlling Brix Content, Uncovers the Influence of Sugars on the Levels of Fruit Hormones, and Demonstrates the Importance of Sucrose Cleavage for Normal Fruit Development and FertilityPlant Physiology, 2009
- Gene and Metabolite Regulatory Network Analysis of Early Developing Fruit Tissues Highlights New Candidate Genes for the Control of Tomato Fruit Composition and DevelopmentPlant Physiology, 2009
- Molecular biology of ethylene during tomato fruit development and maturationPlant Science, 2008
- The intersection between cell wall disassembly, ripening, and fruit susceptibility to Botrytis cinereaProceedings of the National Academy of Sciences of the United States of America, 2008
- A Reevaluation of the Key Factors That Influence Tomato Fruit Softening and IntegrityPlant Physiology, 2007
- Tomato aromatic amino acid decarboxylases participate in synthesis of the flavor volatiles 2-phenylethanol and 2-phenylacetaldehydeProceedings of the National Academy of Sciences of the United States of America, 2006
- Ripening in the tomato Green-ripe mutant is inhibited by ectopic expression of a protein that disrupts ethylene signalingProceedings of the National Academy of Sciences of the United States of America, 2006
- Changes in Transcriptional Profiles Are Associated with Early Fruit Tissue Specialization in TomatoPlant Physiology, 2005
- Cleavage of Structural Proteins during the Assembly of the Head of Bacteriophage T4Nature, 1970