Overproduction of ascorbic acid impairs pollen fertility in tomato
- 2 February 2021
- journal article
- research article
- Published by Oxford University Press (OUP) in Journal of Experimental Botany
- Vol. 72 (8), 3091-3107
- https://doi.org/10.1093/jxb/erab040
Abstract
Ascorbate is a major antioxidant buffer in plants. Several approaches have been used to increase the ascorbate content of fruits and vegetables. Here, we combined forward genetics with mapping-by-sequencing approaches using an ethyl methanesulfonate (EMS)-mutagenized Micro-Tom population to identify putative regulators underlying a high-ascorbate phenotype in tomato fruits. Among the ascorbate-enriched mutants, the family with the highest fruit ascorbate level (P17C5, up to 5-fold wild-type level) had strongly impaired flower development and produced seedless fruit. Genetic characterization was performed by outcrossing P17C5 with cv. M82. We identified the mutation responsible for the ascorbate-enriched trait in a cis-acting upstream open reading frame (uORF) involved in the downstream regulation of GDP-l-galactose phosphorylase (GGP). Using a specific CRISPR strategy, we generated uORF-GGP1 mutants and confirmed the ascorbate-enriched phenotype. We further investigated the impact of the ascorbate-enriched trait in tomato plants by phenotyping the original P17C5 EMS mutant, the population of outcrossed P17C5 × M82 plants, and the CRISPR-mutated line. These studies revealed that high ascorbate content is linked to impaired floral organ architecture, particularly anther and pollen development, leading to male sterility. RNA-seq analysis suggested that uORF-GGP1 acts as a regulator of ascorbate synthesis that maintains redox homeostasis to allow appropriate plant development.Keywords
Funding Information
- Aquitaine region (20111201002, 22000932)
- Syngenta Seeds SAS
- Plant Biology and Breeding Division of INRAE
- Département Sciences de l’Environnement at the University of Bordeaux
This publication has 71 references indexed in Scilit:
- STAR: ultrafast universal RNA-seq alignerBioinformatics, 2012
- clusterProfiler: an R Package for Comparing Biological Themes Among Gene ClustersOMICS: A Journal of Integrative Biology, 2012
- SNP Discovery and Linkage Map Construction in Cultivated TomatoDNA Research, 2010
- Gene regulation in parthenocarpic tomato fruitJournal of Experimental Botany, 2009
- Gene expression studies in kiwifruit and gene over-expression in Arabidopsis indicates that GDP-L-galactose guanyltransferase is a major control point of vitamin C biosynthesisJournal of Experimental Botany, 2009
- Expression profiling of ascorbic acid-related genes during tomato fruit development and ripening and in response to stress conditionsJournal of Experimental Botany, 2009
- A Second GDP-l-galactose Phosphorylase in Arabidopsis en Route to Vitamin COnline Journal of Public Health Informatics, 2008
- Riboswitch-dependent gene regulation and its evolution in the plant kingdomGenes & Development, 2007
- Arabidopsis VTC2 Encodes a GDP-l-Galactose Phosphorylase, the Last Unknown Enzyme in the Smirnoff-Wheeler Pathway to Ascorbic Acid in PlantsOnline Journal of Public Health Informatics, 2007
- The missing step of the l -galactose pathway of ascorbate biosynthesis in plants, an l -galactose guanyltransferase, increases leaf ascorbate contentProceedings of the National Academy of Sciences of the United States of America, 2007