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: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.
Project description:The ripening of climacteric fruits, such as apple, is represented by a series of genetically programmed events orchestrated by the action of several hormones. In this work, we investigated the existence of a hormonal crosstalk between ethylene and auxin during the post-harvest ripening of three internationally known apple cultivars: ‘Golden Deli-cious’, ‘Granny Smith’ and ‘Fuji’. The normal climacteric ripening was impaired by the exogenous application of 1-methylcyclopropene (1-MCP) that effectively affected the production of ethylene and the physiological behaviour of specific ethylene-related qual-ity traits, such as fruit texture and the production of volatile organic compounds showed a de-novo accumulation of auxin following the application of 1-MCP. The RNA-Seq wide-transcriptome analysis evidenced as the competition at the level of the ethylene re-ceptors induced a cultivar-dependent transcription re-programming. The DEGs annota-tion carried out through the KEGG database identified as most genes were assigned to the plant hormone signaling transduction category, and specifically related to auxin and ethylene. The interplay between these two hormones was further assessed through a candidate gene analysis that highlighted a specific activation of GH3 and ILL genes, en-coding key steps in the process of the auxin homeostasis mechanism. Our results showed that a compromised ethylene metabolism at the onset of the climacteric ripening in apple can stimulate, in a cultivar-dependent fashion, an initial de-novo synthesis and de-conjugation of auxin as a tentative to restore a normal ripening progression.
Project description:Here, we conducted an tandem mass tag (TMT)-based proteomics analysis of apple fruit development over five growth stages. Our objective was to gain a global overview of the dynamics of apple fruit development and identify key regulatory networks and proteins that contribute to fruit development and the metabolism and accumulation of sugars and acids for fruit quality improvement.
Project description:Gene expression associated with apple fruit ripening and postharvest treatments was studied to identify transcripts that are regulated by ethylene signaling.
Project description:Analysis of the transcription profiles in tubers of S. tuberosum L. cv. Ditta grown in two experimental seasons under either conventional or organic crop management.
Project description:Apple is one of the most popular fruit crops world-wide and its skin color is an important quality consideration essential for commercial value. However, the strategy on genetic breeding for red skin apple and the genetic basis of skin color differentiation is very limited and still largely unknown. Here, we reported a bud sport mutant of Fuji apple with red skin color and enhanced anthocyanins accumulation. Quantitative SWATH-MS (sequential window acquisition of all theoretical spectra-mass spectrometry) proteomics investigations revealed proteome changes in the apple red skin bud mutation and a total of 411 differentially expressed proteins were identified in apple skin. The mutant showed significantly increased expression levels of photosynthesis-related proteins, stress-related proteins as well as anthocyanins biosynthesis pathway. On the other hand, substanial downregulation of mitogen-activated protein kinase 4 (MAPK4) and mevalonate kinase (MVK) were detected. We also hypothesize that a post-transcriptional regulation of the skin color formation occurs in the mutant through the advanced SWATH-MS analysis. Overall, our work provide important information on the application of proteomic methods for analysing proteomes changes in Fuji apple and highlights a clade of regulatory proteins potentially contributed to the fruit skin color formation.
Project description:Russeting of apple fruit is a non-invasive physiological disorder. It occurs mainly in 'Golden Delicious' apple and its hybrids, while understanding of its molecular mechanism is still limited. In this study, we used mRNA sequencing and an isobaric tag for relative and absolute quantitation-based quantitative (iTRAQ) proteomic analysis to detect changes in the expression levels of genes and proteins during russeting formation in russeted and non-russeted skin of 'Golden Delicious' apple. We set up three comparison groups representing the three developmental stages in the russeting formation process. With the formation of fruit russeting, there were 2856 differentially expressed genes and 942 differentially expressed proteins in the comparison groups as detected at the transcript level and protein level, respectively. A correlation analysis of the transcriptome and proteome data revealed related-genes involved in lignin biosynthesis are significant changes at different developmental stages during apple russeting formation. Some other transcription factors, such as MYBs, NACs and LIMs were also involved in apple russeting formation. In this study, one LIM transcription factor was preliminarily determined to be involved in lignin biosynthesis by combining to PAL-box element. Studying the identified genes and proteins will provide further insights into the molecular mechanisms controlling apple russeting formation.