Project description:A role of chromatin in plant memory of environmental stress has been proposed. In this study ChIP-Seq was employed to investigate whether a transient mild salt treatment of Arabidopsis thaliana plant at seedling stage (M-^Qpriming treatmentM-^R: 50 mM NaCl for 24 hours) altered genome-wide profiles of four histone modifications; H3K4me2, H3K4me3, H3K9me2 and H3K27me3. Comparison of histone modification profiles between primed and non-primed plants harvested immediately after the priming treatment showed differences in all histone modifications but were strongest and most abundant for H3K27me3. We subsequently explored whether these changes were maintained over an extensive period of growth in control conditions. Additional ChIP-Seq analysis showed that differences in the H3K27me3 profiles between primed and non-primed plants were still apparent after a growth period of ten days in control conditions. The results provide first indication for a potential role of H3K27me3 in long-term somatic memory of abiotic stress events in plants. The obtained dataset was compared with RNA-seq data measured in the same plant material (see parallel submission of RNA-Seq data in ArrayExpress: https://www.ebi.ac.uk/arrayexpress/experiments/E-MTAB-1668).
Project description:CuZn-superoxide dismutase (CuZn-SOD) and ascorbate peroxidase (APX) constitute first line of defence against oxidative stress. In the present study, PaSOD and RaAPX genes from Potentilla atrosanguinea and Rheum australe, respectively were overexpressed individually as well as in combination in Arabidopsis thaliana. We performed RNA-seq analysis of wild type and transgenic Arabidopsis thaliana overexpressing CuZn-SOD, APX and CuZn-SOD + APX under control and salt stress
Project description:Arabidopsis thaliana is a glycophyte with a low salt tolerance, while Eutrema is a halophyte with a very high salt tolerance. To elucidate the transcriptional basis of this difference, we performed hydroponis culture experiments where we grew plants under control conditions (25 mM NaCl) or under salt stress (200 mM NaCl for both species, 500 mM for Eutrema). Salt concentration was increased for the stress treatments by increments of 50 mM per day (25 mM on the first day). Plants were grown at the final NaCl concentration for an additional week, when rosettes were harvested for RNA isolation.Expression patterns were compared between treatments and between species.
Project description:A relationship between transcript level and histone modifications is apparent in steady state but their dynamic relationship remains to be understood. In this study we used RNA-sequencing to determine transcript levels in Arabidopsis thaliana plants after a short, mild salt treatment at seedling stage (モpriming treatmentヤ: 50 mM NaCl for 24 hours). The obtained dataset was compared with genome-wide histone modification landscapes measured in the same plant material (see parallel submission of ChIP-Seq data in ArrayExpress: https://www.ebi.ac.uk/arrayexpress/experiments/E-MTAB-1663).
Project description:Plants must continuously react to the ever-fluctuating nature of their environment. Repeated exposure to stressful conditions can lead to priming, whereby prior encounters heighten a plant’s ability to respond to future events. A clear example of priming is provided by the model plant species Arabidopsis thaliana (Arabidopsis), in which photosynthetic and photoprotective responses are enhanced following recurring light stress. While there are various post-translational mechanisms underpinning photoprotection, an unresolved question is the relative importance of transcriptional changes towards stress priming and, consequently, the potential contribution from DNA methylation – a heritable chemical modification of DNA capable of influencing gene expression. Here, we systematically investigate the potential molecular underpinnings of physiological priming against recurring excess light (EL), specifically DNA methylation and transcriptional regulation: the latter having not been examined with respect to EL priming. The capacity for physiological priming of photosynthetic and photoprotective parameters following a recurring EL treatment was not impaired in Arabidopsis mutants with perturbed establishment, maintenance and removal of DNA methylation, nor was the transmission of this priming into naive tissues developed in the absence of excess light. Importantly, no differences in developmental or basal photoprotective capacity were identified in the mutants that may confound the above result. Little evidence for a causal transcriptional component of physiological priming was identified; in fact, most alterations in primed plants presented as a transcriptional ‘dampening’ in response to an additional EL exposure, likely a consequential of physiological priming. However, a set of transcripts uniquely regulated in primed plants provide preliminary evidence for a novel transcriptional component of recurring EL priming, independent of physiological changes. Thus, we propose that physiological priming of recurring EL in Arabidopsis occurs independently of DNA methylation; and that the majority of the associated transcriptional alterations are a consequence, not cause, of this physiological priming.
Project description:The seed differential proteins of the two varieties were mainly in nucleus, chloroplast and mitochondriaredox. The proteins related to homeostasis, electron transfer activity, photosynthesis and carbohydrate metabolism were significantly affected by salt priming.
Project description:Arabidopsis thaliana is a glycophyte with a low salt tolerance, while Eutrema is a halophyte with a very high salt tolerance. To elucidate the transcriptional basis of this difference, we performed hydroponis culture experiments where we grew plants under control conditions (25 mM NaCl) or under salt stress (200 mM NaCl for both species, 500 mM for Eutrema). Salt concentration was increased for the stress treatments by increments of 50 mM per day (25 mM on the first day). Plants were grown at the final NaCl concentration for an additional week, when rosettes were harvested for RNA isolation.Expression patterns were compared between treatments and between species. In total, 15 samples were hybridized. They were derived from three independent biological experiments (replicate_1 to replicate_3). Controlds were grown at 25 mM NaCl, salt stressed plants at either 200 mM NaCl or 500 mM NaCl.
Project description:To investigate differences in plant responses to salt and ABA stimulus, differences in gene expression in Arabidopsis in response to salt and ABA were compared using an Agilent oligo microarray. Four-week-old Arabidopsis thaliana ecotype Columbia (Col-0) seedlings were treated with either 150 mM NaCl or 10 μM ABA for 6 hours; unstressed seedlings (control sample) were collected in parallel to avoid the possible effects of circadian rhythms. The results revealed that 31 genes were up regulated by both NaCl and ABA stress, and 23 genes were down-regulated by these stressors. To provide further validation of our microarray experiment data, ten genes from this signature were quantified in the same RNA samples by quantitative real-time PCR.