The ascorbic acid content of tomato fruits is associated with the expression of genes involved in pectin degradation

BMC Plant Biology

Research Article

Alberto Ferrarini¹  Mario Pezzotti¹  Massimo Delledonne¹  Luigi Frusciante²  Amalia Barone²  Antonio Di Matteo²  Milena Anacleria²  Adriana Sacco² 

[1] Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134, Verona, Italy;Department of Soil, Plant, Environment and Animal Sciences, University of Naples "Federico II", Via Università 100, 80055, Portici, Italy;

关键词: Pectin;    Tomato Fruit;    Ethylene Biosynthesis;    Introgression Line;    AdoMet;   

DOI  :  10.1186/1471-2229-10-163

 received in 2010-01-21, accepted in 2010-08-06,  发布年份 2010

来源: Springer

【 摘 要 】

BackgroundHigh levels of ascorbic acid (AsA) in tomato fruits provide health benefits for humans and also play an important role in several aspects of plant life. Although AsA metabolism has been characterized in detail, the genetic mechanisms controlling AsA accumulation in tomatoes are poorly understood. The transcriptional control of AsA levels in fruits can be investigated by combining the advanced genetic and genomic resources currently available for tomato. A comparative transcriptomic analysis of fruit tissues was carried out on an introgression line containing a QTL promoting AsA accumulation in the fruit, using a parental cultivar with lower AsA levels as a reference.ResultsIntrogression line IL 12-4 (S. pennellii in a S. lycopersicum background) was selected for transcriptomic analysis because it maintained differences in AsA levels compared to the parental genotypes M82 and S. pennellii over three consecutive trials. Comparative microarray analysis of IL 12-4 and M82 fruits over a 2-year period allowed 253 differentially-expressed genes to be identified, suggesting that AsA accumulation in IL 12-4 may be caused by a combination of increased metabolic flux and reduced utilization of AsA. In particular, the upregulation of a pectinesterase and two polygalacturonases suggests that AsA accumulation in IL12-4 fruit is mainly achieved by increasing flux through the L-galactonic acid pathway, which is driven by pectin degradation and may be triggered by ethylene.ConclusionsBased on functional annotation, gene ontology classification and hierarchical clustering, a subset of the 253 differentially-expressed transcripts was used to develop a model to explain the higher AsA content in IL 12-4 fruits in terms of metabolic flux, precursor availability, demand for antioxidants, abundance of reactive oxygen species and ethylene signaling.

【 授权许可】

Unknown   
© Di Matteo et al; licensee BioMed Central Ltd. 2010. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.