Project description:Genome-wide DNA methylation analysis between long-term in vitro shoot culture and acclimatized apple plants DNA methylation is a process of epigenetic modification that can alter the functionality of a genome. Using whole-genome bisulfite sequencing, this study quantify the level of DNA methylation in the epigenomes of two diploid apple (Malus x domestica) scion cultivars ('McIntosh' and 'Húsvéti rozmaring') derived from three environmental conditions: in vivo mother plants in an orchard, in vitro culture, and acclimatized in vitro plants. The global DNA methylation levels were not dependent on the source of plant material. Significant differences in DNA methylation were identified in 586 out of 45,116 genes, including promoter and coding sequences, and classified as differentially methylated genes (DMGs). Differential methylation was visualised by an MA plot and functional genomic maps were established for biological processes, molecular functions and cellular components. Considering the DMGs, in vitro tissue culture resulted in the highest level of methylation, which decreased after acclimatization and tended to be similar to that in the mother tree. Methylation patterns of the two scions differed, indicating cultivar-specific epigenetic regulation of gene expression during adaptation to various environments. After selecting genes that displayed differences larger than ±10% in CpG and CHG contexts, or larger than ±1.35% in the CHH context from among the DMGs, they were annotated in Blast2GO v5.1.12 for Gene Ontology. These DNA methylation results suggest that epigenetic changes may contribute to the adaptation of apple to environmental changes by modifying gene expression.
Project description:We performed Illumina sequencing of sRNA libraries prepared from juvenile and reproductive phase buds from the apple trees. A large number of sRNAs exemplified by 33 previously annotated miRNAs and 6 novel members displayed significant differential expression (DE) patterns in juvenile and reproductive stages. The study provides new insight into our understanding of fundamental mechanism of poorly studied phase transitions in apple and other woody plants and important resource for future in-depth research in the apple development.
Project description:Fire blight (FB) is a bacterial disease affecting plants from Rosaceae family, including apple and pear. FB develops after the infection of Erwinia amylovora, gram-negative enterobacterium, and results in burnt-like damages and wilting, which can affect all organs of the plant. Although the mechanisms underlying disease response in apples are not elucidated yet, it has been well described that FB resistance depends on the rootstock type. The main objective of this work was to identify miRNAs involved in response to bacterial infection in order to better explain apple defense mechanisms against fire blight disease. We performed deep sequencing of eighteen small RNA libraries obtained from inoculated and non-inoculated Gala apple leaves. 233 novel plant mature miRNAs were identified together with their targets and potential role in response to bacterial infection. We identify three apple miRNAs responding to inoculation (mdm-miR168a,b, mdm-miR194C and mdm-miR1392C) as well as miRNAs reacting to bacterial infection in a rootstock-specific manner (miR395 family). Our results provide insights into the mechanisms of fire blight resistance in apple.
Project description:miRNAs are key players in multiple biological processes, therefore analysis and characterization of these small regulatory RNAs is a critical step towards better understanding of animal and plant biology. In apple (Malus domestica) two hundred microRNAs are known, which most probably represents only a fraction of miRNAome diversity. As a result, more effort is required to better annotate miRNAs and their functions in this economically important species. We performed deep sequencing of twelve small RNA libraries obtained for fire blight resistant and fire blight sensitive trees. In the sequencing results we identified 116 novel microRNAs and confirmed a majority of previously reported apple miRNAs. We then experimentally verified selected candidates with RT-PCR and stem-loop qPCR and performed differential expression analysis. Finally, we identified and characterized putative targets of all known apple miRNAs. In this study we considerably expand the apple miRNAome by identifying and characterizing dozens of novel microRNAs. Moreover, our data suggests that apple microRNAs might be considered as regulators and markers of fire blight resistance.
Project description:Our data showed that lipid and glucose metabolic pathways genes were expressed at higher levels in gluteofemoral adipocyte fraction in pears, while genes associated with inflammation were higher in both abdominal and gluteofemoral apple adipocyte fraction. Gluteofemoral adipocyte chromatin from pear-shaped women contained a significantly higher number of differentially open ATAC-seq peaks relative to chromatin from the apple-shaped gluteofemoral adipocytes. In contrast, abdominal adipocyte chromatin openness showed few differences between apple and pear-shaped women. We revealed a correlation between gene transcription and open chromatin at the proximity of the TSS of some of the differentially expressed genes.