Project description:Apple (Malus domestica Borkh) is an important fruit crop cultivated in a broad range of environmental conditions. Apple fruit, and specifically peel tissue, ripening is a physiological process whose molecular regulatory networks response to different environments are still not sufficiently investigated. In this study, the influence of low (20 m) and high (750 m) altitude environmental conditions in peel tissue was assessed by physiological measurements combined with global metabolite and protein expression profiling during apple fruit development and ripening. Although apple fruit ripening was unaffected by the different environmental conditions, however several key color parameters, such as redness and the color percentage index, were induced by high altitude. Consistent with this, increased level of anthocyanin and other phenolic compounds, including cyanidin-3-O-galactoside, quercetin-3-O-rhamnoside, quercetin-3-O-rutinoside and chlorogenic acid were identified in apple peel at high altitude. Also, high altitude environment, particularly, at the ripening period, up-accumulated various carbohydrates (eg., arabinose, xylose and sucrose) while repressed glutamic acid and several related proteins such as glycine hydroxymethyltransferase and glutamate–glyoxylate aminotransferase. Other processes affected by high altitude concerned the TCA cycle, the synthesis of oxidative/defense enzymes, and the accumulation of photosynthetic proteins. Finally, we constructed a metabolite-protein network depicting the impact of altitude on peel ripening. These data provide insights into physiological processes linked to apple peel ripening across different climatic conditions and will assist in efforts to improve apple fruit appeal and quality.
Project description:Apple (Malus domestica Borkh) is an important fruit crop cultivated in a broad range of environmental conditions. Apple fruit, and specifically peel tissue, ripening is a physiological process whose molecular regulatory networks response to different environments are still not sufficiently investigated. In this study, the influence of low (20 m) and high (750 m) altitude environmental conditions in peel tissue was assessed by physiological measurements combined with global metabolite and protein expression profiling during apple fruit development and ripening. Although apple fruit ripening was unaffected by the different environmental conditions, however several key color parameters, such as redness and the color percentage index, were induced by high altitude. Consistent with this, increased level of anthocyanin and other phenolic compounds, including cyanidin-3-O-galactoside, quercetin-3-O-rhamnoside, quercetin-3-O-rutinoside and chlorogenic acid were identified in apple peel at high altitude. Also, high altitude environment, particularly, at the ripening period, up-accumulated various carbohydrates (eg., arabinose, xylose and sucrose) while repressed glutamic acid and several related proteins such as glycine hydroxymethyltransferase and glutamate���glyoxylate aminotransferase. Other processes affected by high altitude concerned the TCA cycle, the synthesis of oxidative/defense enzymes, and the accumulation of photosynthetic proteins. Finally, we constructed a metabolite-protein network depicting the impact of altitude on peel ripening. These data provide insights into physiological processes linked to apple peel ripening across different climatic conditions and will assist in efforts to improve apple fruit appeal and quality.
Project description:Papaya (Carica papaya L.) is a typical climacteric fruit, undergoing massive physico-chemical changes during ripening. Although papaya is widely cultivated and consumed, few studies have characterized the variations in metabolism during its ripening process at the proteasome level. Using an integrated approach involving Tandem Mass Tag labeling and liquid chromatography–mass spectrometry analysis, proteomes of papaya fruit at different ripening stages were investigated. A total of 3220 proteins were identified, of which 2818 were quantified. The differential accumulated proteins (DAPs) exhibited various biological functions and diverse subcellular localizations. Among the DEPs, most of the pathogen defense-related proteins were down-regulated, suggesting that disease resistance decreased during the ripening process. The Kyoto Encyclopedia of Genes and Genomes enrichment analysis revealed that various metabolic pathways were significantly altered, particularly in flavonoid and fatty acid metabolisms. The up-regulation of several flavonoid biosynthesis-related proteins may provide more raw materials for pigment biosynthesis, accelerating the color variation of papaya fruit. Thus, variations in the fatty acid metabolism-related enzymes were investigated. For example, a lipoxygenase, which catalyzes the conversion of ACC to ethylene, was significantly induced, suggesting a cross-talk between the lipoxygenase-mediated fatty acid metabolism and the hormone-controlled fruit ripening in papaya. Furthermore, the contents of several important fatty acids were determined, and increased unsaturated fatty acids may be associated with papaya fruit volatile formation. Our data may give an intrinsic explanation of the variations in metabolism during the ripening process of papaya fruit and serve as a comprehensive resource for investigating the regulation mechanism involved.
Project description:Background: Fruit color is an important quality trait for nutrition value in tomato (Solanum lycopersicum) and has attracted huge attention for a long time. In order to dissect the yellow-fruit color of a novel tomato mutant n3122, we compared the dynamic transcriptome of the fruit pericarps from the mutant n3122 and its wild type red-fruited tomato cultivar M82. Results: The transcriptomes of fruits from M82 35 DPA (Days Post Anthesis), M82 47 DPA, M82 54 DPA, n3122 35 DPA, n3122 47 DPA, n3122 54 DPA and n3122 60 DPA were sequenced using an Illumina Hiseq 2000 sequencing platform. A total of 5568 differentially expressed genes (DEGs) were commonly identified in the four pairwise comparisons of M82_35 DPA vs n3122_35 DPA, M82_47 DPA vs n3122_47 DPA, M82_54 DPA vs n3122_54 DPA and M82_47 DPA vs n3122_60 DPA. Further Gene Ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses revealed that carotenoids biosynthesis, ethylene biosynthesis and signaling transduction, and transcription factors associated fruit ripening were different between M82 and n3122 which might be the underlying mechanisms for the yellow-fruit color of tomato. Conclusions: This research provided a global data set of dynamic transcriptomic changes during fruit development and ripening for the wild type red-fruited tomato cultivar M82 and its yellow-fruited mutant n3122, and offered a base for elucidating the molecular mechanisms underlying tomato red/yellow fruit color mutation.
Project description:Molecular events regulating apple fruit ripening and sensory quality are largely unknown. Such knowledge is essential for genomic-assisted apple breeding and postharvest quality management. In this study, a parallel transcriptome profile analysis, scanning electron microscopic (SEM) examination and systematic physiological characterization were performed on two apple cultivars, Honeycrisp (HC) and Cripps Pink (CP), which have distinct ripening features and texture attributes. Systematic physiological characterization of fruit ripening based on weekly maturity data indicated substantial differences in fruit crispness and firmness at comparable ripening stages. SEM images of fruit cortex tissues prepared from fruits with equivalent maturity suggested that the cell wall thickness may contribute to the observed phenotypes of fruit firmness and crispness. A high-density long-oligo apple microarray consisting of duplex 190,135 cross-hybridization-free 50-70-mer isothermal probes, and representing 23,997 UniGene clusters, was manufactured on a Nimblegen array platform. Transcriptome profiling identified a total of 1793 and 1209 UniGene clusters differentially expressed during ripening from cortex tissues of HC and CP, respectively. UniGenes implicated in hormone metabolism and response, cell wall biosynthesis and modification and those encoding transcription factors were among the prominent functional groups. Between the two cultivars, most of the identified UniGenes were similarly regulated during fruit ripening; however, a short list of gene families or specific family members exhibited distinct expression patterns between the two cultivars, which may represent candidate genes regulating cultivar-specific apple fruit ripening patterns and quality attributes. Using a single color labeling system, a total of 24 microarray slides were utilized, one for each cortex tissue sample, for transcriptome profiling analysis. 2 cultivars x 3 developmental stages x 4 biological replicates.
Project description:The ripening process of olive fruits is associated with chemical and/or enzymatic specific transformations making them particularly attractive to animals and humans. Usually, there is a progressive chromatic change characterized by a final red-brown color of both epidermis and mesocarp. This event has an exception in the ‘Leucocarpa’ cultivar, in which we observed the destabilization in the equilibrium between the metabolism on chlorophyll and that of the other pigments, particularly the anthocyanins, whose switch-off during maturation promotes the white coloration of the fruits. Recently, transcription profiling of ripening olives from ‘Leucocarpa’ and ‘Cassanese’ cultivars, through an Illumina RNA-seq approach, has provided some information about genes involved in fruit maturation as flavonid and anthocyanin transcripts. To study the possible gene differences involved in flavonoids and anthocyanins biosynthetic pathways during ripening possibly caused by small nuclear RNA (snRNA) in olive drupes, the snRNA libraries of fruit ripening from ‘Leucocarpa’ and ‘Cassanese’ were constructed with RNAs from drupes at 100 and 130 DAF (Days After Flowering) and sequenced by Illumina approach. Comparing sequence information, 130 conserved microRNAs (miRNA) in the Viridiplantae were detected belonging 14 miRNA families. For the remaining read not-matched with known miRNAs in the Viridiplantae, we combined secondary structure and minimum free energy to discover novel olive miRNAs. Based on these analyses, 492 miRNAs were considered as putative novel. To increase insights into the functions of known and putative novel miRNA in olive, putative target genes were computationally predicted by alignment with the olive drupe transcripts obtained from the same samples. A total of 32 and 186 transcripts were predicted as targets of 130 known and 492 putative novel miRNA, respectively. The identified target genes are involved in a broad range of biological processes. Interestingly, some genes involved in negative regulation of anthocyanin metabolic process, were identified as target of miR168 suggesting that this miRNA family is likely operative during color transition in olive.
Project description:Kumquat (Fortunella classifolia Swingle) was thought as a close relative to citrus according to fruit morphology taxonomic, but kumquat fruit as well as its flowering characteristic are distinct from other citrus species, the trees usually blooms on the medium of June, obviously later than other citrus species, moreover many kumquat accessions could be blossom more than one times during one growth season, as this reason, the kumquat fruits could be consecutively ripen over several months, which made the study of globe genes expression profile for different development stage fruit easy. Kumquat is non-climacteric fruit, however the kumquat fruit ripening process, especially genes expression change in young and ripe kumquat fruits are less known, so studying on the global genes expression profiles of kumquat fruits in young and ripe stage are especially helpful to identify ripening-related genes and unravel the mechanism of ripening process.
Project description:DNA methylation is a conserved epigenetic mark that influences diverse biological processes in many eukaryotes. Recently, DNA methylation was proposed to regulate fleshy fruit ripening. Fleshy fruits can be distinguished by their ripening process as climacteric fruits, such as tomatoes, or non-climacteric fruits, such as strawberries. Tomatoes undergo a global decrease in DNA methylation during ripening, due to increased expression of a DNA demethylase gene. The dynamics and biological relevance of DNA methylation during ripening of non-climacteric fruits, or other climacteric fruits, are unknown. Here, we generated and characterized single-base resolution maps of the DNA methylome in strawberry fruit, from immature to ripe stages. We observed an overall loss of DNA methylation during strawberry fruit ripening. Thus, ripening-induced DNA hypomethylation occurs not only in climacteric fruit, but also in non-climacteric fruit. However, we discovered that the mechanisms underlying DNA hypomethylation during ripening of tomato and strawberry are distinct. Unlike in tomatoes, DNA demethylase genes were not up-regulated during ripening of strawberries. Instead, genes involved in RNA-directed DNA methylation were down-regulated during strawberry ripening. Further, ripening-induced DNA hypomethylation was associated with decreased siRNA levels, consistent with reduced RdDM activity. Therefore, we propose that DNA hypomethylation during strawberry ripening is caused by diminished RdDM activity. Finally, hundreds of ripening-related genes displayed altered expression that was associated with, and thus potentially regulated by, DNA hypomethylation during ripening. Our findings provide new insight into the DNA methylation dynamics during the ripening of non-climateric fruit and reveal a novel function of RdDM in regulating an important process in plant development.