Project description:Fruit ripening in Citrus is not well understood at the molecular level. Knowledge of the regulatory mechanism of citrus fruit ripening at the post-transcriptional level in particular is lacking. Here, we comparatively analyzed the miRNAs and their targeted genes in a spontaneous late-ripening mutant, ?Fengwan? sweet orange (MT) (Citrus sinensis L. Osbeck), and its wild-type counterpart ('Fengjie 72-1', WT). Using high-throughput sequencing of small RNAs and RNA degradome tags, we identified 107 known and 21 novel miRNAs, as well as 225 target genes. A total of 24 miRNAs (16 known miRNAs and 8 novel miRNAs) were shown to be differentially expressed between MT and WT. The expression pattern of several key miRNAs and their target genes during citrus fruit development and ripening stages was examined. Csi-miR156k, csi-miR159 and csi-miR166d suppressed specific transcription factors (GAMYBs, SPLs and ATHBs) that are supposed to be important regulators involved in citrus fruit development and ripening. In the present study, miRNA-mediated silencing of target genes was found under complicated and sensitive regulation in citrus fruit. The identification of miRNAs and their target genes provide new clues for future investigation of mechanisms that regulate citrus fruit ripening.
Project description:[original title] Understanding the complexity of fruit ripening by transcriptome analysis of rin mutant fruit and in silico analysis of promoters of differentially regulated genes A tomato MADS-box transcription factor, LeMADS-RIN, controls fruit ripening and mutation in this gene results in non-ripening phenotype of fruit. This mutation down-regulates certain ripening related ethylene responses, however, other ethylene responses are normal. A complete understanding of this mutation and its effect on fruit transcriptome during ripening is not clear. In this study, microarray analysis has been used to investigate the influence of rin mutation on fruit transcriptome at different stages of ripening. A total of 2,398 genes were found to be differentially expressed in wild type fruit pericarp, which on cluster analysis indicated a major shift in their expression profiles in rin mutant fruit. A total of 1,802 genes were found to be differentially expressed between wild type and rin mutant fruits and 17% of these genes encoded regulatory elements, suggesting that mutation in LeMADS-RIN results in disturbance in the regulatory transcriptional networks during ripening. Since LeMADS-RIN has been reported to bind to the CArG box of LeACS2 promoter, in-silico analysis of 51 putative promoter sequences of the genes, that showed ripening associated up-regulation in wild type but showed impairment in up-regulation in rin mutant fruit during ripening, were searched for presence of CArG box along with ethylene and auxin responsive elements. The study revealed that only 24 putative promoter sequences harbor LeMADS-RIN specific CArG box suggesting an alternative mode of regulation by LeMADS-RIN for CArG box deficient genes. Three chronological stages of tomato (Solanum lycopersicon) fruit ripening were compared between wild type and rin mutant
Project description:[original title] Understanding the complexity of fruit ripening by transcriptome analysis of rin mutant fruit and in silico analysis of promoters of differentially regulated genes A tomato MADS-box transcription factor, LeMADS-RIN, controls fruit ripening and mutation in this gene results in non-ripening phenotype of fruit. This mutation down-regulates certain ripening related ethylene responses, however, other ethylene responses are normal. A complete understanding of this mutation and its effect on fruit transcriptome during ripening is not clear. In this study, microarray analysis has been used to investigate the influence of rin mutation on fruit transcriptome at different stages of ripening. A total of 2,398 genes were found to be differentially expressed in wild type fruit pericarp, which on cluster analysis indicated a major shift in their expression profiles in rin mutant fruit. A total of 1,802 genes were found to be differentially expressed between wild type and rin mutant fruits and 17% of these genes encoded regulatory elements, suggesting that mutation in LeMADS-RIN results in disturbance in the regulatory transcriptional networks during ripening. Since LeMADS-RIN has been reported to bind to the CArG box of LeACS2 promoter, in-silico analysis of 51 putative promoter sequences of the genes, that showed ripening associated up-regulation in wild type but showed impairment in up-regulation in rin mutant fruit during ripening, were searched for presence of CArG box along with ethylene and auxin responsive elements. The study revealed that only 24 putative promoter sequences harbor LeMADS-RIN specific CArG box suggesting an alternative mode of regulation by LeMADS-RIN for CArG box deficient genes.
Project description:The aim of this study is to generate gene regulatory networks by analyzing Affymetrix GeneChip expression datasets from four different stages of tomato fruit ripening, Breaker (Br), Turning (Tu), Pink (Pk) and Red Ripe (RR) with the LeMoNe algorithm in order to identify co expression modules and their putative regulatory TFs.
Project description:To excavate the underlying molecular regulation network that during citrus fruit development and ripening, we used RNA-seq to generate high-resolution profiles of global gene expression in four different fruit tissues at six development stages. Using weighted gene coexpression network analysis, we identified modules of coexpressed genes and hub genes of tissue-specific networks. In general, this study was aimed to uncover the new molecular insights into citrus fruit development and ripening, and to reveal the specific nonclimacteric characteristics of citrus fruit.
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: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.
Project description:Here, we used RNA sequencing and tandem mass tag (TMT)–based quantitative proteomics technology to study the comprehensive mRNA and protein expression changes during fruit development and ripening in watermelon. A total of 6,226 proteins were quantified, and the number of quantitative proteins is the largest in fruit proteome to date, comparable to studies in model organisms such as rice and Arabidopsis. Omics analysis showed that smaller changes occurred in protein abundance compared to mRNA abundance. Furthermore, protein and transcript abundance were poorly correlated, and the correlation coefficients decreased during fruit development and ripening. Our comprehensive transcriptomic and proteomic data offer a valuable resource for watermelon research, and provide new insights into the molecular mechanisms underlying complex regulatory networks of fruit ripening in watermelon.