Project description:Purpose: This study was to explore the underlying molecular mechanism of temperature effects on fruit quality during shelf life. The transcriptome data of peach fruits stored in high temperature (HT, 35 °C) and common temperature (CT, 25 °C) conditions were measured and compared. Methods: Red flesh peach (Prunus persica L. Batsch cv. Tianxianhong) fruits with consistent color, shape and weight were selected and kept at 5 °C for 2 days after the day of harvest. Then, these fruits were randomly divided into two groups. One group was stored at CT for 7 days, and the other was stored at HT for 7 days. During storage, fruits were sampled at day 1, 2 and 3 as early stage as well as day 5, 6 and 7 as later stage. Total RNA of each sample was extracted and used to construct 24 RNA libraries. RNA sequencing was performed on an Illumina HiSeq 2500 platform. The differences in transcriptome, ethylene production, pulp softening of postharvest peach fruits were compared between CT and HT storage conditions Results: Our results showed that HT conditioning after 5 °C is better than CT to maintaining fruit quality during shelf life due to MEKK1-MKK2-MPK4/6 signal transduction and low level of ethylene and auxin biosynthesis enzymes which may affect genes related to softening and membrane stability through ethylene response factors (ERFs) and auxin response factors (ARFs).
Project description:Background Field observations and a few physiological studies pointed out that peach embryogenesis and fruit development are strictly related. In fact, attempts to stimulate parthenocarpic fruit development by means of external tools failed. Moreover, physiological disturbances during the early embryo development lead to seed abortion and fruitlet abscission. Later on, the interactions between seed and fruit development become less stringent. Genetic and molecular information about seed and fruit development in peach is limited. Results The isolation of 455 genes differentially expressed in seed and fruit was done by means of a comparative analysis of the transcription profiles carried out in peach (Prunus persica, cv Fantasia) seed and mesocarp throughout development by means of µPEACH 1.0, the first peach microarray. Genes differentially expressed in the two organs and specific of developmental stages had been identified, and some were validated as markers. Genes representative of the main functional categories are present, among which several transcription factors such as MADS-box, bZIP, Aux/IAA, AP2, WRKY, and HD. Some of these showed a similar transcription profile in the two organs, while others displayed an opposite pattern, being more expressed in embryo at early development and in mesocarp at ripening. Conclusions The µPEACH1.0, although developed from ripe fruit ESTs, resulted in being suitable for studying seed/mesocarp interactions. Among the differentially expressed genes, marker genes specific for organ and stage of development have been selected. Comparisons were carried out by pooling stage 1 and 2 (named early development, e) and stage 3 and 4 (named late development, l), separately for mesocarp (M) and seed (S) of cultivar Fantasia, and using a simple loop experimental design. RNA has been extracted from fruit harvest at above-mentioned stages of development. At least four hybridizations have been conducted for a total of four technical replicates (with dye-swap).
Project description:Background Field observations and a few physiological studies pointed out that peach embryogenesis and fruit development are strictly related. In fact, attempts to stimulate parthenocarpic fruit development by means of external tools failed. Moreover, physiological disturbances during the early embryo development lead to seed abortion and fruitlet abscission. Later on, the interactions between seed and fruit development become less stringent. Genetic and molecular information about seed and fruit development in peach is limited. Results The isolation of 455 genes differentially expressed in seed and fruit was done by means of a comparative analysis of the transcription profiles carried out in peach (Prunus persica, cv Fantasia) seed and mesocarp throughout development by means of µPEACH 1.0, the first peach microarray. Genes differentially expressed in the two organs and specific of developmental stages had been identified, and some were validated as markers. Genes representative of the main functional categories are present, among which several transcription factors such as MADS-box, bZIP, Aux/IAA, AP2, WRKY, and HD. Some of these showed a similar transcription profile in the two organs, while others displayed an opposite pattern, being more expressed in embryo at early development and in mesocarp at ripening. Conclusions The µPEACH1.0, although developed from ripe fruit ESTs, resulted in being suitable for studying seed/mesocarp interactions. Among the differentially expressed genes, marker genes specific for organ and stage of development have been selected.
Project description:Comprehensive investigation of gene expression during fruit development and ripening in European pear (Pyrus communis). Gene expression of fruit flesh development of European pear was measured from -7 to 182 days after full bloom (DAFB). 150 DAFB is harvested stage and 182 DAFB is after ripening by chilling treatment (2M-BM-0C 12 days, then 15M-BM-0C 20 days).
Project description:The fruit of melting-flesh peach cultivars produce high levels of ethylene caused by high expression of PpACS1, resulting in rapid fruit softening at the late-ripening stage. In contrast, the fruit of stony hard peach cultivars do not soften and produce little ethylene due to low expression of PpACS1. To elucidate the mechanism for suppressing PpACS1 expression in stony hard peaches, a microarray analysis was performed. Several genes that displayed similar expression patterns as PpACS1 were identified and shown to be IAA-inducible genes.
Project description:A transcriptome analysis was applied on two peach (Prunus persica L.) cultivars with different sensitivity to low temperature regimes to identify cold-responsive genes that might be involved in tolerance to long low temperature storage. Peach fruit from ‘Morettini No2’ and ‘Royal Glory’, a sensitive and a tolerant, to chilling injury cultivars, respectively, were harvested at commercial maturity stage and allowed to ripen at room temperature (25°C) or subjected to 4 and 6-weeks of cold storage (0°C, 95% R.H.) followed by ripening at room temperature. Microarray experiments, employing the peach microarray platform (μ PEACH 1.0), were carried out by comparing harvested fruit against 4- and 6-week cold-stored fruit. The analysis identified 173 and 313 genes that were differentially expressed in ‘Morettini No2’ and ‘Royal Glory’ fruit after 4 weeks, respectively. However, the 6 weeks cold storage provoked a decrease in the total number of genes differentially expressed in both cultivars. RNA blot analysis validated the differential expression of certain genes showed in microarray data. Among these genes, two heat shock proteins (hsps), a putative β-D-xylosidase, an expansin, a dehydrin and a pathogenesis-related protein PR-4B precursor were induced during cold storage in both cultivars. The induction of hsps and the putative β-D-xylosidase appeared to be independent on the duration of postharvest treatment. On the other hand, transcript levels of lipoxygenase were quite constant during postharvest ripening, while a strong reduction or disappearance was observed after cold storage. A dehydration-induced RD22-like protein showed a reduction in the accumulation of transcripts during postharvest ripening independently on the temperature conditions. Overall, the current study shed some light on the molecular aspects of cold stress in peach fruit quality and identified some ripening and/or cold-induced genes which function need further elucidation.
Project description:The fruit of melting-flesh peach cultivars produce high levels of ethylene caused by high expression of PpACS1, resulting in rapid fruit softening at the late-ripening stage. In contrast, the fruit of stony hard peach cultivars do not soften and produce little ethylene due to low expression of PpACS1. To elucidate the mechanism for suppressing PpACS1 expression in stony hard peaches, a microarray analysis was performed. Several genes that displayed similar expression patterns as PpACS1 were identified and shown to be IAA-inducible genes. Change in gene expression according to growth of fruits in 'melting peach M-bM-^@M-^XAkatsukiM-bM-^@M-^Y fruit sampled at 92, 98, 104 and 106 day after full bloom (DAB). Propylene induced gene expression stony peach M-bM-^@M-^XManamiM-bM-^@M-^Y and M-bM-^@M-^XOdorokiM-bM-^@M-^Y harvested at commercial maturity (Tatsuki et al., 2006).
Project description:MicroRNAs play critical roles in various biological and metabolic processes. The function of miRNAs has been widely studied in model plants such as Arabidopsis and rice. However, the number of identified miRNAs and related miRNA targets in peach (Prunus persica) is limited. To understand further the relationship between miRNAs and their target genes during tissue development in peach, a small RNA library and three degradome libraries were constructed from three tissues for deep sequencing. We identified 117 conserved miRNAs and 186 novel miRNA candidates in peach by deep sequencing and 19 conserved miRNAs and 13 novel miRNAs were further evaluated for their expression by RT-qPCR. The number of gene targets that were identified for 26 conserved miRNA families and 38 novel miRNA candidates, were 172 and 87, respectively. Some of the identified miRNA targets were abundantly represented as conserved miRNA targets in plant. However, some of them were first identified and showed important roles in peach development. Our study provides information concerning the regulatory network of miRNAs in peach and advances our understanding of miRNA functions during tissue development. To identify more conserved and peach-speciM-oM-,M-^Ac miRNAs and their target genes and to understand further the mechanism of miRNA-regulated target genes during tissue development in peach, a small RNA library and three degradome libraries were constructed from three different tissues for deep sequencing.