Polyethylene glycol sorbitan monoacylates (Tween) are detergents of widespread use in plant sciences. We show them, notably Tween 20, to cause a rapid and complex change in transcript abundance which bears all characteristics of a PAMP / elicitor-induced defense response, and they do so at concentrations which cause no detectable deleterious effects on plant cellular integrity. The activity does not reside in the intact Tween molecule itself, but is caused by medium-chain fatty acids, notably lauric acid (LA), which are efficiently released from the Tween-backbone by the plant. The Tween / LA-response is independent of the jasmonate signalling system. Medium-chain fatty acids are thus novel elicitors/regulators of plant pathogen defense. The results also have several practical implications: (i) The use of Tweens and, as we show, several other detergents, as solvating/wetting agents on intact plants causes profound physiological changes which may mask actual effects of test compounds; (ii) Tweens by themselves can be regarded (and probably used) as economical, non-toxic, and safe-to-apply elicitors of inducible plant immunity against pathogens.
A novel regulatory system in plants involving medium-chain fatty acids.
Age
View SamplesThis SuperSeries is composed of the SubSeries listed below.
No associated publication
Specimen part
View SamplesThe objective of the study was to assess the technical error due to blending of individual samples into pools in experimental data.
No associated publication
No sample metadata fields
View SamplesRegulation of genes in shoots and roots and Arabidopsis in response to Zn-deficiency in wild-type and hma2 hma4 mutants plants
Systemic Upregulation of MTP2- and HMA2-Mediated Zn Partitioning to the Shoot Supplements Local Zn Deficiency Responses.
Age, Specimen part
View SamplesThe transition between growth in the dark (skotomorphogenesis) and growth in the light (photomorphogenesis) is one of the most critical in plant development. Here the newly identified mutant dez is photomorphogenic in the dark and is strongly enhanced in high Zn. dez displays a shortened hypocotyl, expanded cotyledons, an elongated root and differentiated plastids in the dark contrast to wild-type seedlings that are typically skotomorphogenic, with a long hypocotyl and unexpanded cotyledons protected by an apical hook, and undifferentiated etioplasts
No associated publication
Specimen part
View SamplesGene copy number variation (CNV) is a form of genetic polymorphism that contributes significantly to genome size and function but remains poorly characterized due to technological limitations. Inter-specific comparisons of CNVs in recently diverged plant species are crucial to uncover selection patterns underlying adaptation of a species to stressful environments. Especially given that gene amplifications have long been implicated in emergence of species-specific traits, we conducted a genome-wide survey to identify species-specific gene copy number expansions and deletions in the model extremophile species - Arabidopsis halleri that has diverged in evolutionarily recent time from Arabidopsis thaliana.
Between-species differences in gene copy number are enriched among functions critical for adaptive evolution in Arabidopsis halleri.
Specimen part
View SamplesThe methyl-cytosine binding protein 2 (MeCP2) is a reader of epigenetic DNA methylation marks and necessary and sufficient to reorganize 3D heterochromatin structure during cellular differentiation, e.g., myogenesis. In addition to global expression profile changes, myogenic differentiation is accompanied by 3D-heterochromatin reorganization that is dependent on MeCP2. MeCP2 is enriched at pericentric heterochromatin foci (chromocenters). During myogenesis, the total heterochromatin foci number per nucleus decreases while foci volumes and MeCP2 protein levels increase. Ectopic MeCP2 is able to mimic similar heterochromatin restructuring in the absence of differentiation.
Gene repositioning within the cell nucleus is not random and is determined by its genomic neighborhood.
Specimen part, Cell line
View SamplesAbiotic stress is a major factor for crop productivity, a problem likely to be exacerbated by climate change. Improving the tolerance to environmental stress is one of the most important goals of crop breeding programmes. While the early responses to abiotic stress in plants are well studied, plant adaptation to enduring or recurring stress conditions has received little attention. This project investigates the molecular mechanism of the maintenance of acquired thermotolerance as a model case of stress memory in Arabidopsis. Arabidopsis seedlings acquire thermotolerance through a heat treatment at sublethal temperatures. To investigate the underlying mechanisms, we are investigating changes in the transcriptome at two timepoints after a heat acclimation treatment using Arabidopsis thaliana seedlings.
Arabidopsis miR156 Regulates Tolerance to Recurring Environmental Stress through SPL Transcription Factors.
Treatment
View SamplesTransposable elements (TEs) make up a large proportion of eukaryotic genomes. As their mobilization creates genetic variation that threatens genome integrity, TEs are epigenetically silenced through several pathways and this may spread to neighboring sequences. JUMONJI (JMJ) proteins can function as anti-silencing factors and prevent silencing of genes next to TEs. Whether TE silencing is counterbalanced by the activity of anti-silencing factors is still unclear. Here, we characterize JMJ24 as a regulator of TE silencing. We show that loss of JMJ24 results in increased silencing of the DNA transposon AtMu1c, while overexpression of JMJ24 reduces silencing. JMJ24 has a JumonjiC (JmjC) domain and two RING domains. JMJ24 auto-ubiquitinates in vitro, demonstrating E3 ligase activity of the RING domain(s). JMJ24-JmjC binds the N-terminal tail of histone H3 and full-length JMJ24 binds histone H3 in vivo. JMJ24 activity is anti-correlated with histone H3 lysine 9 dimethylation (H3K9me2) levels at AtMu1c. Double mutant analyses with epigenetic silencing mutants suggest that JMJ24 antagonizes histone H3K9me2, and requires H3K9 methyltransferases for its activity on AtMu1c. Genome-wide transcriptome analysis indicates that JMJ24 affects silencing at additional TEs. Our results suggest that the JmjC domain of JMJ24 has lost demethylase activity but has been retained as a binding domain for histone H3. This is in line with phylogenetic analyses indicating that JMJ24 [with the mutated JmjC domain] is widely conserved in angiosperms. Taken together, this study assigns a role in TE silencing to a conserved JmjC-domain protein with E3 ligase activity, but no demethylase activity.
A JUMONJI Protein with E3 Ligase and Histone H3 Binding Activities Affects Transposon Silencing in Arabidopsis.
No sample metadata fields
View SamplesWe performed a comprehensive molecular and cellular analysis of primary dermal fibroblasts taken from a patient with recurrent cancers, harboring a BRCA1 mosaic epimutation (BRCA1mosMe) in comparison to their isogenic control fibroblasts (BRCA1wt), taken from the patients healthy monozygous sister.
No associated publication
Specimen part, Disease
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