Cold induced changes: differences between the Arabidopsis thaliana wild type and freezing sensitive mutants.
Ontology highlight
ABSTRACT:
ORGANISM(S): Arabidopsis thaliana
PROVIDER: GSE5711 | GEO | 2007/01/08
SECONDARY ACCESSION(S): PRJNA96999
REPOSITORIES: GEO
Similar Datasets
Project description:Arabidopsis sfr mutants are deficient in cold acclimation during exposure to coolnon-freezing temperatures. Although not visibly affected by the cold they have lost the ability to survive subsequent freezing. We plan to investigate how the sfr2 and sfr6 mutants respond to low temperature on the gene expression level. Wild type plants that have undergone identical treatments in parallel are necessary controls. The cold treatment of plants in the rosette stage (soil grown in a 8/16 hours day/night cycle) will be carried out in a cooled growth chamber at 4 degrees for 24 hours (same light regimetreatment starting/ending at the 4th hour of light). The aerial parts of the treated and untreated plants will be collected and frozen immediately in liquid nitrogen for RNA extraction. Comparison of the cold response of thousands of Arabidopsis genes in the wild type to the situation in our freezing sensitive mutants will enhance our understanding of the cold response itself and illuminate the effect of the mutations on the cold acclimation process. Experimenter name = Irene Bramke; Experimenter phone = 01784 44 3770; Experimenter fax = 01784 43 4326; Experimenter address = Royal Holloway; Experimenter address = University of London; Experimenter address = School of Biological Sciences; Experimenter address = Bourne Building; Experimenter address = Laboratory 406; Experimenter zip/postal_code = TW20 OEX; Experimenter country = UK Experiment Overall Design: 6 samples were used in this experiment
2008-06-14 | E-GEOD-5711 | biostudies-arrayexpress
Project description:Freezing causes physiological changes even in a hardy, cold-acclimated wild type. During recovery from freezing, gene expression will reflect the induction of damage-repair processes distinct from the damage-prevention associated with cold acclimation. This will be detected by observing the wild-type transcriptome at two time points during recovery from a freezing episode. The appropriate control is the unfrozen, cold-acclimated wild type. Experimenter name = Glenn Thorlby Experimenter phone = 01874 443770 Experimenter address = School of biological Sciences Experimenter address = Bourne Building Experimenter address = Royal Holloway Experimenter address = Egham Experimenter zip/postal_code = TW20 0EX Keywords: growth_condition_design;
2006-08-15 | GSE5524 | GEO
Project description:Freezing causes physiological changes even in a hardy, cold-acclimated wild type. During recovery from freezing, gene expression will reflect the induction of damage-repair processes distinct from the damage-prevention associated with cold acclimation. This will be detected by observing the wild-type transcriptome at two time points during recovery from a freezing episode. The appropriate control is the unfrozen, cold-acclimated wild type. Experimenter name = Glenn Thorlby; Experimenter phone = 01874 443770; Experimenter address = School of biological Sciences; Experimenter address = Bourne Building; Experimenter address = Royal Holloway; Experimenter address = Egham; Experimenter zip/postal_code = TW20 0EX Experiment Overall Design: 3 samples were used in this experiment
2008-06-13 | E-GEOD-5524 | biostudies-arrayexpress
Project description:Our goals are to discover the basis of the stress-sensitive phenotypes of the sfr2, sfr3 and sfr6 mutants, and to distinguish damage-repair from damage-prevention-related transcription in the wild type. The effects of sfr2 and sfr3 on cold-induced gene expression will be observed. Since sfr6 causes sensitivity to drought as well as freezing, the effects of sfr6 on the transcriptional response to drought is studied; an observation of cold-induced sfr6 expression is needed for direct comparison to the effect of drought. Unstressed mutants, and equivalently-stressed wild types, are necessary controls. The above experiments are conducted on tissue-culture-grown plants grown under 24 hr illumination for maximum reproducibility and comparability to other transcriptomic experiments.Freezing causes physiological changes even in a hardy, cold-acclimated wild type. During the recovery period, gene expression will reflect the induction of damage-repair processes distinct from the damage-prevention associated with cold acclimation. This will be detected by observing the wild-type transcriptome at two time points during recovery from a freezing episode. The appropriate controls is the unfrozen, cold-acclimated wild type. Plants for this experiment will be soil-grown in an 9/15 day/night cycle to the rosette stage, and this regime will be maintained during acclimation and freezing treatments.Cold-induction will be 10 days at 4°C; drought will be imposed by placing excised leaves in a desiccator for 6 h. The youngest fully-expanded rosette leaves will be harvested for RNA extraction. Keywords: stimulus_or_stress_design; strain_or_line_design; time_series_design
2007-01-22 | GSE6177 | GEO
Project description:Our goals are to discover the basis of the stress-sensitive phenotypes of the sfr2, sfr3 and sfr6 mutants, and to distinguish damage-repair from damage-prevention-related transcription in the wild type. The effects of sfr2 and sfr3 on cold-induced gene expression will be observed. Since sfr6 causes sensitivity to drought as well as freezing, the effects of sfr6 on the transcriptional response to drought is studied; an observation of cold-induced sfr6 expression is needed for direct comparison to the effect of drought. Unstressed mutants, and equivalently-stressed wild types, are necessary controls. The above experiments are conducted on tissue-culture-grown plants grown under 24 hr illumination for maximum reproducibility and comparability to other transcriptomic experiments.Freezing causes physiological changes even in a hardy, cold-acclimated wild type. During the recovery period, gene expression will reflect the induction of damage-repair processes distinct from the damage-prevention associated with cold acclimation. This will be detected by observing the wild-type transcriptome at two time points during recovery from a freezing episode. The appropriate controls is the unfrozen, cold-acclimated wild type. Plants for this experiment will be soil-grown in an 9/15 day/night cycle to the rosette stage, and this regime will be maintained during acclimation and freezing treatments.Cold-induction will be 10 days at 4°C; drought will be imposed by placing excised leaves in a desiccator for 6 h. The youngest fully-expanded rosette leaves will be harvested for RNA extraction. Experiment Overall Design: Number of plants pooled:18
2008-06-14 | E-GEOD-6177 | biostudies-arrayexpress
Project description:The sfr6 mutant was identified on the basis of its failure to cold acclimate, and exhibits a marked deficiency in cold-and osmotic stress-inducible gene expression (Knight et al., 1999). We have demonstrated that genes of this type (so-called COR genes) are misregulated if they contain the DRE (drought-responsive element, or CRT; C-repeat) cis acting element in their promoter (Boyce et al., 2003). Micro-array analysis has allowed us to identify a number of COR genes misregulated in sfr6, all of which contain the DRE element. However, these experiments have indicated that other genes, not of the COR group, are also misregulated in the mutant and these do not contain the DRE element. We chose the three non-COR genes that were most clearly down-regulated in sfr6 on our previous micro-array, and identified each as of these as dark-inducible. We now seek to address two questions: (1) Can we discover more dark-regulated genes that are down-regulated in the mutant, and thus identify a second cis-acting element with which SFR6 may be interacting? (2) Do all of the non-COR genes that are misregulated in sfr6 fall into the category of dark-inducible, or is SFR6 likely to be interacting with three or more regulons? For this micro-array experiment, we will subject sfr6 and wild type Arabidopsis, grown in a 16/8-h light/dark cycle, to darkness for 3h or 6h at ambient growth temperature. Under these conditions we see strong up-regulation of the three genes we have identified as dark-inducible, and we see clear down-regulation of expression in sfr6. References. Knight H, Veale E, Warren GJ, Knight MR (1999) The sfr6 mutation in Arabidopsis suppresses low-temperature induction of genes dependent on the CRT/DRE sequence motif. Plant Cell 11: 875-886. Boyce JM, Knight H, Deyholos M, Openshaw MR, Galbraith DW, Warren G, Knight MR (2003). The sfr6 mutant of Arabidopsis is defective in transcriptional activation via CBF/DREB1 and DREB2 and shows sensitivity to osmotic stress. Plant Journal 34: 395-406. Experimenter name = Heather Knight Experimenter phone = 01865 275023 Experimenter fax = 01865 275074 Experimenter institute = University of Oxford Experimenter address = Department of Plant Sciences Experimenter address = University of Oxford Experimenter address = South Parks Road Experimenter address = Oxford Experimenter zip/postal_code = OX1 3RB Experimenter country = UK Keywords: growth_condition_design; genetic_modification_design
2007-01-08 | GSE5710 | GEO
Project description:The sfr6 mutant was identified on the basis of its failure to cold acclimate, and exhibits a marked deficiency in cold-and osmotic stress-inducible gene expression (Knight et al., 1999). We have demonstrated that genes of this type (so-called COR genes) are misregulated if they contain the DRE (drought-responsive element, or CRT; C-repeat) cis acting element in their promoter (Boyce et al., 2003). Micro-array analysis has allowed us to identify a number of COR genes misregulated in sfr6, all of which contain the DRE element. However, these experiments have indicated that other genes, not of the COR group, are also misregulated in the mutant and these do not contain the DRE element. We chose the three non-COR genes that were most clearly down-regulated in sfr6 on our previous micro-array, and identified each as of these as dark-inducible. We now seek to address two questions: (1) Can we discover more dark-regulated genes that are down-regulated in the mutant, and thus identify a second cis-acting element with which SFR6 may be interacting? (2) Do all of the non-COR genes that are misregulated in sfr6 fall into the category of dark-inducible, or is SFR6 likely to be interacting with three or more regulons?; For this micro-array experiment, we will subject sfr6 and wild type Arabidopsis, grown in a 16/8-h light/dark cycle, to darkness for 3h or 6h at ambient growth temperature. Under these conditions we see strong up-regulation of the three genes we have identified as dark-inducible, and we see clear down-regulation of expression in sfr6. References. Knight H, Veale E, Warren GJ, Knight MR (1999) The sfr6 mutation in Arabidopsis suppresses low-temperature induction of genes dependent on the CRT/DRE sequence motif. Plant Cell 11: 875-886. Boyce JM, Knight H, Deyholos M, Openshaw MR, Galbraith DW, Warren G, Knight MR (2003). The sfr6 mutant of Arabidopsis is defective in transcriptional activation via CBF/DREB1 and DREB2 and shows sensitivity to osmotic stress. Plant Journal 34: 395-406. Experimenter name = Heather Knight; Experimenter phone = 01865 275023; Experimenter fax = 01865 275074; Experimenter institute = University of Oxford; Experimenter address = Department of Plant Sciences; Experimenter address = University of Oxford; Experimenter address = South Parks Road; Experimenter address = Oxford; Experimenter zip/postal_code = OX1 3RB; Experimenter country = UK Experiment Overall Design: 4 samples were used in this experiment
2008-06-14 | E-GEOD-5710 | biostudies-arrayexpress
Project description:Our analysis of the sfr6 freezing-sensitive mutant (Knight, H., Veale, E., Warren, G. J. and Knight, M. R. (1999). Plant Cell 11, 875-886.) and cls8 (unpublished) chilling-sensitive mutant of Arabidopsis, has revealed that the expression of certain cold-regulated genes is aberrant in both these mutants. In order to understand the molecular basis of chilling and freezing stress in Arabidopsis and also to determine commonalities and differences between these 2 different physiological stress-tolerance processes, we request transcriptome analysis for both of these mutants compared to wild type in one experiment, upon cold treatment and at ambient conditions. The sfr6 mutant shows the most severe phenotype with respect to cold gene expression, but is tolerant to chilling (Knight, H., Veale, E., Warren, G. J. and Knight, M. R. (1999). Plant Cell 11, 875-886.). However, it is unable to cold acclimate and hence is sensitive to freezing. The cls8 mutant, on the other hand, has a relatively mild phenotype relative to the cold-regulated genes we have examined, but is very sensitive to chilling temperatures (15 to 10 degree centigrade). It is thus likely that in cls8 we have not yet identified the genes which are most affected, and which account for the physiological phenotype. Both sfr6 and cls8 have been fine-mapped and are close to being cloned. The cls8 mutant has an altered calcium signature in response to cold which means it is likely to be affected in early signalling, e.g. cold perception itself.We will compare the expression profiles of genes in sfr6, cls8 and Columbia (parental line for both mutants), both at ambient, and after treatment with cold (5 degrees) for 3 hours. This timepoint is designed to Âcapture both rapidly responding genes e.g. CBF/DREB1 transcription factors, and also more slow genes e.g. COR genes (KIN1/2 and LTI78). Pilot northerns confirm that this time point is suitable.This analysis will provide new insight into 2 novel genes required for tolerance to low temperature in Arabidopsis, and additionally will determine the nature of overlap between the separate processes of chilling and freezing tolerance. Experiment Overall Design: Number of plants pooled:40-60
2008-06-14 | E-GEOD-6167 | biostudies-arrayexpress
Project description:The sfr6-1 mutant of Arabidopsis has been shown to be defective in freezing tolerance and fails to express a number of cold-regulated genes to normal wild type levels. The aim of this experiment was to test whether two other mutant alleles, sfr6-2 and sfr6-3 showed similar defects in cold-inducible gene expression.
2014-12-22 | GSE46084 | GEO
Project description:Plants in temperate regions have evolved mechanisms to survive sudden temperature drops. Previous reports have indicated that the cold acclimation mechanism is light-dependent and does not fully operate under a low light intensity. In these studies, plants were grown under a long-day photoperiod and were more sensitive to freezing stress. However, winter annuals like Arabidopsis thaliana Col-0 germinate in the fall, overwinter as rosettes, and therefore must acclimate under short photoperiods and low irradiance. The role of light intensity was analysed in plants grown under a short-day photoperiod at the growth stage 1.14. Plants were acclimated at 4 °C for seven days under 100 and 20 μmol m-2s-1 PPFD for control and limited-light conditions, respectively. All cold acclimated plants accumulated molecular markers reportedly associated with acquired freezing tolerance, including proline, sucrose, CBFs, and COR gene protein products dehydrins and low-temperature-responsive proteins LTIs. Observed changes indicated that low PPFD did not inhibit the cold acclimation process, and the freezing stress experiment confirmed similar survival rates. The molecular analysis found distinct PPFD-specific adaptation mechanisms that were manifested in contrasting content of anthocyanins, cytokinin conjugates, abundances of proteins forming photosystems, and enzymes of protein, energy, and ROS metabolism pathways. Finally, this study led to the identification of putative proteins and metabolite markers correlating with susceptibility to freezing stress of non-acclimated plants grown under low PPFD. Our data show that Arabidopsis plants grown under short-day photoperiod can be fully cold-acclimated under limited light conditions, employing standard and PPFD-specific pathways.
2021-07-08 | PXD025234 | Pride