The type-A response regulators negatively mediate heat stress response by altering redox homeostasis in Arabidopsis
Ontology highlight
ABSTRACT:
INSTRUMENT(S): Orbitrap Fusion Lumos
ORGANISM(S): Arabidopsis Thaliana (mouse-ear Cress)
TISSUE(S): Whole Body
SUBMITTER: 
Martin Cerny
LAB HEAD: Martin Cerny
PROVIDER: PXD034173 | Pride | 2022-09-09
REPOSITORIES: Pride
Similar Datasets
Project description:Cytokinin is an indispensable phytohormone responsible for a number of physiological processes ranging from root development to leaf senescence. The term “cytokinin” refers to several dozen adenine-derived compounds which occur naturally in plants, including the model plant Arabidopsis thaliana. Cytokinins (CKs) can be divided up into various classes and forms; the base forms are generally considered to be active while highly abundant cytokinin-N-glucosides (CKNGs), which are composed of a CK base irreversibly conjugated to a glucose molecule, are considered inactive. However, results from early CK studies suggest CKNGs do not always lack activity despite the perpetuation in the literature that they are inactive. Here we show that exogenous application of CKNGs to Arabidopsis tissue results in a CK response comparable to the application of an active CK base. These results are most apparent in senescence assays in which both a CK base (tZ) and CKNGs (tZ7G, tZ9G) delay senescence in cotyledons. Further physiological experiments involving root growth and shoot regeneration revealed CKNGs do not always have the same effects as CK bases, and these compounds have largely distinct effects on the transcriptome, as well as the proteome. These data are in direct contradiction to previous reports of CKNGs being inactive and raise questions about the function of these compounds as well as their mechanism of action. Because CKNGs make up the majority of CKs in Arabidopsis and other Angiosperms, it is especially important to understand their physiological effects in order to have a more holistic understanding of this essential phytohormone.
2020-05-27 | PXD016087 | Pride
Project description:<p>Cytokinin (CK) in plants regulates both developmental processes and adaptation to environmental stress. <em>Arabidopsis histidine phosphotransfer ahp2,3,5</em> and type-B<em> response regulator arr1,10,12</em> triple mutants are almost completely defective in CK signaling, and the <em>ahp2,3,5</em> mutant was reported to be salt tolerant. Here, we demonstrate that the <em>arr1,10,12</em> mutant is also more tolerant to salt stress than wild-type plants. A comprehensive metabolite profiling coupled with transcriptome analysis of the<em> ahp2,3,5</em> and <em>arr1,10,12</em> mutants was conducted to elucidate the salt tolerance mechanisms mediated by CK signaling. Numerous primary (e.g., sugars, amino acids and lipids) and secondary (e.g., flavonoids and sterols) metabolites accumulated in these mutants under both non-saline and saline conditions, suggesting that both pre- and post-stress accumulation of stress-related metabolites contribute to improved salt tolerance in CK-signaling mutants. Specifically, the level of oligosaccharides, amino acids [e.g., proline and gamma-aminobutyric acid], anthocyanins, sterols, and unsaturated triacyglycerols, were higher in the mutant plants than in wild-type plants. Notably, the reprograming of flavonoid and lipid pools was highly coordinated and concomitant with changes in transcriptional levels, indicating that these metabolic pathways are transcriptionally regulated by CK signaling. The discovery of the regulatory role of CK signaling on membrane lipid remodelling provides a greater understanding of CK-mediated salt tolerance in plants. This knowledge will contribute to the development of salt-tolerant crops with the ability to withstand salinity as a key driver to ensure global food security in the era of climate change.</p>
2021-11-25 | MTBLS2532 | MetaboLights
Project description:The cold acclimation process is regulated by many factors like ambient temperature, day length, light intensity, or hormonal status. Experiments with plants grown under different light-quality conditions indicate that the plant response to cold is also a light-quality-dependent process. Here, the role of light quality in the cold response was studied in one-month-old Arabidopsis thaliana (Col‐0) plants exposed for one week to 4 °C at short‐day conditions under white (100 and 20 μmol m‐2s‐1), blue or red (20 μmol m‐2s‐1) light conditions. An upregulated expression of CBF1, an inhibition of photosynthesis, and an increase in membrane damage showed that blue light enhanced the effect of low temperature. Interestingly, cold-treated plants under blue and red light showed only limited freezing tolerance compared to white light cold-treated plants. Next, the specificity of the light quality signal in cold response was evaluated in Arabidopsis accessions originating from different and contrasting latitudes. In all but one Arabidopsis accessions, blue light increased the effect of cold on photosynthetic parameters and electrolyte leakage. This effect was not found for Ws-0, which lacks functional CRY2 protein, indicating its role in the cold response. Proteomics data confirmed significant differences between red and blue light treated plants at low temperature and showed that the cold response is highly accession specific. In general, blue light increased mainly the cold-stress related proteins and red light induced higher expression of chloroplast-related proteins, which correlated with higher photosynthetic parameters in red light cold-treated plants. Altogether, our data suggest that light modulates two distinct mechanisms during the cold treatment - red light driven cell function maintaining program and blue light activated specific cold response. The importance of mutual complementarity of these mechanisms was demonstrated by significantly higher freezing tolerance of cold-treated plants under white light.
2022-06-14 | PXD033102 | Pride
Project description:The expression of heat-shock proteins (Hsps) induced by a non-lethal heat treatment confers acquired thermotolerance (AT) to organisms against a subsequent challenge of otherwise lethal temperature. After stress signal lifted, AT gradually decayed with the decline of Hsps during recovery period. The duration of AT may be critical for sessile organisms, such as plants, to survive repeated heat stress in the environment. To identify heat-induced genes involved in duration of AT, we took a reverse-genetics approach by screening for Arabidopsis T-DNA insertion mutants that show decreased thermotolerance after a long recovery at non-stress condition following a conditioning treatment. Among the tested mutants corresponding to 47 genes, only the HsfA2 knockout mutant showed significant phenotype. The mutant plants were more sensitive to severe heat stress than the wild type after long but not short recovery following a pretreatment at 37oC, which can be complemented by introducing a wild-type copy of the gene. Quantitative hypocotyl elongation assay also revealed that AT decayed faster in the absence of HsfA2. Significant decline of the transcript levels of several highly heat-induced genes was observed in the HsfA2 knockout plants after a 4-h recovery or after 2 h of prolonged heat stress. Immunoblot anlysis showed that Hsa32 and class I small Hsp were lower in the mutant than in the wild type after a long recovery. Our results suggest that HsfA2 as a heat-induced transactivator sustains the post-stress expression of Hsp genes and extends the duration of AT in Arabidopsis. Keywords: heat shock response
2006-11-01 | GSE4760 | GEO
Project description:Plants and animals share similar mechanisms in the heat-shock (HS) response, such as synthesis of the conserved HS proteins (Hsps). However, because plants are confined to a growing environment, in general they require unique features to cope with heat stress. We have analyzed the function of a novel Hsp, heat-stress-associated 32-kD protein (Hsa32), which is highly conserved in land plants but absent in most other organisms. The gene responds to HS at the transcriptional level in moss, Arabidopsis, and rice. Like other Hsps, Hsa32 protein accumulates greatly in Arabidopsis seedlings after HS treatment. Disruption of Hsa32 by T-DNA insertion does not affect growth and development under normal conditions. However, the acquired thermotolerance in the knockout line was compromised following a long recovery period (> 24 h) after an acclimation HS treatment, when a severe HS challenge killed the mutant but not the wild-type plants, but no significant difference was observed if they were challenged within a short recovery period. Microarray analysis of the knockout mutant indicates that only the expression of Hsa32 was significantly altered in HS response. Taken together, our results suggest that Hsa32 is not required for the induction but maintenance of acquired thermotolerance. This report provides direct evidence that a plant-specific Hsp plays an important role in thermotolerance. Keywords: heat shock response
2006-03-20 | GSE4062 | GEO
Project description:Plants face temporal and spatial variation in nitrogen (N) availability. This includes heterogeneity in soil nitrate (NO3-) content. To face these constraints, plants modify their gene expression and physiological processes to optimize N acquisition. This plasticity relies on a complex long-distance root-shoot-root signaling network that remains poorly understood. We previously showed that cytokinin (CK) biosynthesis is required to trigger systemic N signaling. Here, we performed split-root experiments and used a combination of CK-related mutant analyses, hormone profiling, transcriptomic analysis, NO3- uptake assays, and root growth measurements to gain insight into systemic N signaling in Arabidopsis thaliana. By comparing wild-type plants and mutants affected in CK biosynthesis and ABCG14-dependent root-to-shoot translocation of CK, we revealed an important role for active trans-Zeatin (tZ) in systemic N signaling. Both rapid sentinel gene regulation and long-term functional acclimation to heterogeneous NO3- supply, including NO3- transport and root growth regulation, are likely mediated by the integration of tZ content in shoots. Furthermore, shoot transcriptome profiling revealed that glutamate/glutamine metabolism is likely a target of tZ root-to-shoot translocation, prompting an interesting hypothesis regarding shoot-to-root communication. Finally, this study highlights tZ-independent pathways regulating gene expression in shoots as well as NO3- uptake activity in response to total N-deprivation. We used microarrays to detail transcriptional reprogramming occurring in shoots in response to heterogeneous nitrate supply compared to homogeneous nitrate supply in wild-type Arabidopsis thaliana plants and in two mutants affected in cytokinin biosynthesis and transport.
2018-05-09 | GSE114162 | GEO
Project description:A genome-wide transcriptome analysis showed that altering ZmPIN1a expression led to wide-ranging gene expression changes. When comparing overexpression lines A17 with the WT, 2975 genes were differentially expressed with 793 up-regulated and 2182 down-regulated in the leaves, and 2129 genes were differentially expressed with 938 up-regulated and 1191 down-regulated in the roots. GO analysis indicated that these differentially expressed genes participate in multiple biological processes from hormone signaling to metabolism. The local biosynthesis, PAT and signaling of auxin were altered; some was directly employed in plant developments such as AUX/IAA, ARFs and genes related to PAT. The genes involved in ethylene, GA, BR CK and ABA metabolism and signaling were altered as well. These phytohormones were also confirmed as key regulators in plant development and abiotic stress responses. Some of the differentially expressed genes between A17 and WT were identified as Arabidopsis root morphology and development mutant genes. These mutants were abnormal in their plant hormone synthesis and signaling, calcium-mediated signaling, MAP kinase signaling, transcription factors, membrane transporters etc. This finding suggested that ZmPIN1a overexpression led to a change of the auxin signaling transduction and even the metabolism of auxin and the metabolism and signaling of other hormones. These events led to changes in the expression of numerous genes and resulted in the modification of plant morphology, especially the root architecture. Maize (Zea mays L.) inbred line DH4866, its ZmPIN1a sense transgenic lines A17 and antisense transgenic lines a55 were used in this study. The transcriptome by altering ZmPIN1a expression was done by comparing the transcriptome of WT and transgenic lines both in root and leaf of V3 stage plants.
2014-05-06 | E-GEOD-57291 | biostudies-arrayexpress
Project description:A genome-wide transcriptome analysis showed that altering ZmPIN1a expression led to wide-ranging gene expression changes. When comparing overexpression lines A17 with the WT, 2975 genes were differentially expressed with 793 up-regulated and 2182 down-regulated in the leaves, and 2129 genes were differentially expressed with 938 up-regulated and 1191 down-regulated in the roots. GO analysis indicated that these differentially expressed genes participate in multiple biological processes from hormone signaling to metabolism. The local biosynthesis, PAT and signaling of auxin were altered; some was directly employed in plant developments such as AUX/IAA, ARFs and genes related to PAT. The genes involved in ethylene, GA, BR CK and ABA metabolism and signaling were altered as well. These phytohormones were also confirmed as key regulators in plant development and abiotic stress responses. Some of the differentially expressed genes between A17 and WT were identified as Arabidopsis root morphology and development mutant genes. These mutants were abnormal in their plant hormone synthesis and signaling, calcium-mediated signaling, MAP kinase signaling, transcription factors, membrane transporters etc. This finding suggested that ZmPIN1a overexpression led to a change of the auxin signaling transduction and even the metabolism of auxin and the metabolism and signaling of other hormones. These events led to changes in the expression of numerous genes and resulted in the modification of plant morphology, especially the root architecture.
2014-05-06 | GSE57291 | GEO
Project description:To understand the role of CK-signaling components in water stress response, we have carried out comparative expression analysis of the CK-signaling ahp4-1 mutant and WT plants under dehydration and well-watered (control) conditions. Aligent’s whole Arabidopsis Gene Expression Microarray (G2519F-021169, V4, 4x44K) was used.
2020-12-01 | GSE95614 | GEO
Project description:We have been determining signalling components essential for heat tolerance in Arabidopsis thaliana (Larkindale, J., and Knight, M.R. (2002). Protection against heat stress-induced oxidative damage in Arabidopsis involves calcium, abscisic acid, ethylene, and salicylic acid. Plant Physiol 128, 682-695). We have most recently found that a heat-induced respiratory burst is necessary for tolerance to high temperatures in Arabidopsis (Larkindale, Torres, Jones and Knight, unpublished). We have observed that one of the Arabidopsis respiratory burst homologues, AtrbohB, is necessary for the generation of this AOS burst in response to heat, and consequently we have also found that an AtrbohB null mutant shows reduced tolerance to heating (Larkindale, Torres, Jones and Knight, unpublished). This mutant also shows reduced expression of genes from the HSP90 family (Evans, Larkindale and Knight, unpublished).This application is for transcriptomic analysis of the AtrbohB null mutant in response to heat, in order to understand which genes are activated as a result of heat-induced respiratory bursts in Arabidopsis and also which genes are necessary for physiological thermotolerance in Arabidopsis. The experiment will involve 6 samples (chips), 3 from wild type Columbia and 3 from the AtrbohB null mutant. Seedlings will be treated at 20, 30 and 40 degrees centigrade for 1 hour, RNA extracted and submitted to microarray analysis. One hour treatment has been shown to display clear differences in HSP90 expression and physiological damage, and the temperatures chosen because 30 degrees is a temperature at which acquired thermotolerance can be initiated (thus genes involved in this process can be monitored) and 40 degrees is a temperature at which we observe physiological damage, and gives good discrimination between mutant and wild type.
2022-11-21 | E-NASC-24 | biostudies-arrayexpress