Transcriptome and metabolome analysis of Citrus fruit to elucidate puffing disorder

Abstract

a b s t r a c tA systems-level analysis reveals details of molecular mechanisms underlying puffing disorder in Citrus fruit. Flavedo, albedo and juice sac tissues of normal fruits and fruits displaying symptoms of puffing disorder were studied using metabolomics at three developmental stages. Microarrays were used to compare normal and puffed fruits for each of the three tissues. A protein-protein interaction network inferred from previous work on Arabidopsis identified hub proteins whose transcripts show significant changes in expression. Glycolysis, the backbone of primary metabolism, appeared to be severely affected by the disorder, based on both transcriptomic and metabolomic results. Significantly less citric acid was observed consistently in puffed fruits. Gene set enrichment analysis suggested that glycolysis and carbohydrate metabolism were significantly altered in puffed samples in both albedo and flavedo. Expression of invertases and genes for sucrose export, amylose-starch and starch-maltose conversion was higher in puffed fruits. These changes may significantly alter source-sink communications. Genes associated with gibberellin and cytokinin signaling were downregulated in symptomatic albedo tissues, suggesting that these hormones play key roles in the disorder. Findings may be applied toward the development of early diagnostic methods based on host response genes and metabolites (i.e. citric acid), and toward therapeutics based on hormones.

Advanced methods of plant disease detection. A review

“…The technology depends on the availability of strong and reliable host and pathogen biomarkers discovered through transcriptomic approaches (Martinelli et al 2012a(Martinelli et al , 2013a. Metabolomics is widely used to identify key plant metabolites of primary and secondary metabolism usable as biomarkers for different environmental stresses or pathogen infections (Rizzini et al 2010;Tosetti et al 2012;Martinelli et al 2012bMartinelli et al , 2013bMartinelli et al , 2014Ibanez et al 2014). An integrated omic approach can identify early pathogen infections such as Huanglongbing disease in citrus (Dandekar et al 2010).…”

Metabolite profiling of Ricinus communis germination at different temperatures provides new insights into thermo-mediated requirements for successful seedling establishment

“…Additionally, these results suggest that there is a thermo-sensitive time window during seed germination in which high temperatures compromise subsequent seedling development. The integration of transcript and metabolite data has been used to pinpoint relevant metabolic pathways for a certain phenotype, as an indication for causal relationship [23][24][25][26]. Here we investigated which biochemical and/or molecular mechanisms occur during seed germination that may be required for proper seedling establishment and are negatively affected by a high temperature.…”

Proposal of a Genome Editing System for Genetic Resistance to Tomato Spotted Wilt Virus

“…Microarray techniques have been shown to be effective tools in characterizing plant or organ stress status (Rizzini et al, 2010). Metabolomics, largely used for the elucidation of plant physiological processes (Tosetti et al, 2012;Martinelli et al, 2011a;2012b;Ibanez et al, 2014) is another potent tool for the identification of metabolic biomarkers for early detection of diseases. Genes involved in phenylpropanoid pathways or chaperones Natali et al, 2007) may be potential targets to characterize plant stress status.…”