Early gibberellin responses in Arabidopsis
Ontology highlight
ABSTRACT:
ORGANISM(S): Arabidopsis thaliana
PROVIDER: GSE8739 | GEO | 2007/11/21
SECONDARY ACCESSION(S): PRJNA105283
REPOSITORIES: GEO
Similar Datasets
Project description:The aim is to identify early gibberellin responsive genes in a gibberellin deficient strain such as ga1-3. Such genes are likely regulated by DELLA proteins which are master gibberellin repressors. DELLA proteins are rapidly degraded after gibberellin treatment, but their direct target genes still need to be elucidated. Experiment Overall Design: A set of 4 biological replicates was generated for each treament. Arabidopsis seedlings were treated with water or 2 uM GA4 and whole shoots collected after 1h. A comparison of water vs. GA4 treated samples should render a list of early gibberellin responsive genes.
2008-06-16 | E-GEOD-8739 | biostudies-arrayexpress
Project description:The aim of this study is to identify early DELLA protein-responsive genes using a Dexamethasone (DEX)-inducible system. Two transgenic lines were used: one induces the expression of a dominant, gibberellin non-responsive DELLA protein (rga-delta17); the other is a control line that carries the same vector, but lacks the rga-delta17 transgene. By comparing the gene expression changes in the line that expresses the rga-delta17 protein in the presence or absence of DEX it is possible to identify putative targets of DELLA proteins. An empty vector transgenic line was included in this study to identify genes that might be regulated by the DEX inducible system that are not dependent on the DELLA protein. Experiment Overall Design: Seedlings of both transgenic lines were pretreated for 16 h with 2 uM GA4 to enhance gibberellin responses. Because DELLA proteins are strong signaling repressors, this pretreatment should maximize the effect of DELLA induction. Eight-day old seedlings were treated with 2 uM GA4 or a combination of 2 uM GA4 plus 10 uM DEX to induce the rga-delta17 transgene. Three biological replicas for the transgenic line that carries the DEX-inducible rga-delta17 transgene were generated at 2h and 4h. For the empty vector line, only 2 biological replicas were generated at 4h of treatment with 2 uM GA with or without 10 uM DEX.
2008-06-16 | E-GEOD-8741 | biostudies-arrayexpress
Project description:DELLA proteins are conserved master growth regulators that play a central role in controlling plant development in response to internal and environmental cues. DELLAs function as transcription regulators, which are recruited to target promoters by binding to transcription factors (TFs) and histone H2A via its GRAS domain. Recent studies showed that DELLA stability is regulated post-translationally via two mechanisms, phytohormone gibberellin-induced polyubiquitination for its rapid degradation, and Small Ubiquitin-like Modifier (SUMO)-conjugation to alter its accumulation. Moreover, DELLA activity is dynamically modulated by two distinct glycosylations: DELLA-TF interactions are enhanced by O-fucosylation, but inhibited by O-linked N-acetylglucosamine (O-GlcNAc) modification. However, the role of DELLA phosphorylation remains unclear. Here, we identified phosphorylation sites in REPRESSOR OF ga1-3 (RGA, an AtDELLA) purified from Arabidopsis by tandem mass spectrometry analysis, and showed that phosphorylation of the RGA LKS-peptide in the poly-S/T region enhances RGA-H2A interaction and RGA association with target promoters. Interestingly, phosphorylation does not affect RGA-TF interactions. Our study has uncovered that phosphorylation is a new regulatory mechanism of DELLA activity.
2024-08-08 | PXD046004 | Pride
Project description:rs09-09_della-dark - della-regulation in darkness versus light - Identification of DELLA-dependent downstream targets in darkness - Aim was to determine downstream target of DELLA proteins involved in skotomorphogenesis. Wt, ga1-3, ga1-3_rga_gai_rgl1_rgl2_rgl3 global seeds were sterilized, sown on MS agar plates then put for stratification for 3 days at 4°C. Plates were placed in growth cabinet at 22°C for 5 days in darkness or in continous light. Keywords: gene knock out
2011-06-13 | GSE22681 | GEO
Project description:The aim of this study is to identify early DELLA protein-responsive genes using a Dexamethasone (DEX)-inducible system. Two transgenic lines were used: one induces the expression of a dominant, gibberellin non-responsive DELLA protein (rga-delta17); the other is a control line that carries the same vector, but lacks the rga-delta17 transgene. By comparing the gene expression changes in the line that expresses the rga-delta17 protein in the presence or absence of DEX it is possible to identify putative targets of DELLA proteins. An empty vector transgenic line was included in this study to identify genes that might be regulated by the DEX inducible system that are not dependent on the DELLA protein. Keywords: Dexamethasone treatment, gibberellin treatment, time course, transgene effect
2007-11-21 | GSE8741 | GEO
Project description:This model is from the article:
Mathematical modeling elucidates the role of transcriptional feedback in gibberellin signaling.
Middleton AM , Úbeda-Tomás S , Griffiths J , Holman T , Hedden P , Thomas SG , Phillips AL , Holdsworth MJ , Bennett MJ , King JR, Owen MR Proc. Natl. Acad. Sci. U.S.A.
2012 May; 109(19): 7571-6 22523240
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Abstract:
The hormone gibberellin (GA) is a key regulator of plant growth. Many of the components of the gibberellin signal transduction [e.g., GIBBERELLIN INSENSITIVE DWARF 1 (GID1) and DELLA], biosynthesis [e.g., GA 20-oxidase (GA20ox) and GA3ox], and deactivation pathways have been identified. Gibberellin binds its receptor, GID1, to form a complex that mediates the degradation of DELLA proteins. In this way, gibberellin relieves DELLA-dependent growth repression. However, gibberellin regulates expression of GID1, GA20ox, and GA3ox, and there is also evidence that it regulates DELLA expression. In this paper, we use integrated mathematical modeling and experiments to understand how these feedback loops interact to control gibberellin signaling. Model simulations are in good agreement with in vitro data on the signal transduction and biosynthesis pathways and in vivo data on the expression levels of gibberellin-responsive genes. We find that GA-GID1 interactions are characterized by two timescales (because of a lid on GID1 that can open and close slowly relative to GA-GID1 binding and dissociation). Furthermore, the model accurately predicts the response to exogenous gibberellin after a number of chemical and genetic perturbations. Finally, we investigate the role of the various feedback loops in gibberellin signaling. We find that regulation of GA20ox transcription plays a significant role in both modulating the level of endogenous gibberellin and generating overshoots after the removal of exogenous gibberellin. Moreover, although the contribution of other individual feedback loops seems relatively small, GID1 and DELLA transcriptional regulation acts synergistically with GA20ox feedback.
2024-09-02 | BIOMD0000000422 | BioModels
Project description:Gibberellin (GA) promotes plant growth by destabilizing DELLA proteins. DELLA proteins integrate multiple hormonal and environmental stress responses. We investigated the role of GA and DELLA proteins in plant defence. We used microarrays to detail the global programme of gene expression controlled by DELLA proteins and identified distinct classes of differentially regulated genes in response to pathogens, hormones or pathogen elicitors.
2010-01-15 | GSE17464 | GEO
Project description:DELLA proteins are members of the GRAS-domain family of transcriptional regulators and modulate transcriptional activity through protein-protein interactions with at least 15 different classes of transcription factor. The plant hormone gibberellin (GA) regulates a range of growth and development responses including promoting cell elongation, by triggering the degradation of DELLA proteins. More than 70% of modern wheat (Triticum aestivum L.) varieties carry alleles encoding DELLA proteins that are resistant to GA-mediated degradation. These alleles result in constitutive growth repression in stem tissues and confer a semi-dwarf growth habit associated with improved lodging resistance. However, these alleles also have negative pleiotropic effects such as reduced nitrogen use efficiency and weak early vigour that restrict their utility in some environments. A detailed understanding of the mechanisms by which DELLA proteins regulate growth and development will be necessary to dissect these responses and develop targeted strategies to breed improved crop varieties. We identified the orthologous C2H2 Zinc-finger transcription factors INDETERMINATE DOMAIN 5 (IDD5) in wheat and SEMI-DWARF3 (SDW3) in barley (Hordeum vulgare) as positive regulators of stem and leaf expansion. Both IDD5 and SDW3 physically interact with DELLA proteins and are epistatic to these genes. We propose a mechanism by which IDD proteins integrate GA signals to modulate downstream gene transcriptional activity through a protein complex dual activation and repression activities. Changes in GA biosynthesis gene expression levels suggest that part of this response involves GA homeostasis. Plants carrying null mutations in IDD5 and SDW3 exhibit a GA-insensitive semi-dwarf growth habit comparable to the Rht-D1b ‘Green Revolution’ allele and have potential as novel dwarfing alleles in cereal breeding programmes.
2024-11-30 | GSE282829 | GEO
Project description:rs09-09_della-dark - della-regulation in darkness versus light - Identification of DELLA-dependent downstream targets in darkness - Aim was to determine downstream target of DELLA proteins involved in skotomorphogenesis. Wt, ga1-3, ga1-3_rga_gai_rgl1_rgl2_rgl3 global seeds were sterilized, sown on MS agar plates then put for stratification for 3 days at 4°C. Plates were placed in growth cabinet at 22°C for 5 days in darkness or in continous light. Keywords: gene knock out 9 dye-swap - CATMA arrays
2011-06-12 | E-GEOD-22681 | biostudies-arrayexpress
Project description:This SuperSeries is composed of the following subset Series:; GSE8739: Early gibberellin responses in Arabidopsis; GSE8741: DELLA protein direct targets in Arabidopsis Experiment Overall Design: Refer to individual Series
2008-06-16 | E-GEOD-8785 | biostudies-arrayexpress