Induction of LHY expression from an alcohol-inducible promoter
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ABSTRACT:
ORGANISM(S): Arabidopsis thaliana
PROVIDER: GSE48366 | GEO | 2014/10/01
SECONDARY ACCESSION(S): PRJNA209852
REPOSITORIES: GEO
Similar Datasets
Project description:The aim of the experiment was to identify transcripts that are regulated by LHY, a MYB transcription factor that functions as part of the Arabidopsis circadian clock. Transgenic plants carrying an ethanol-inducible copy ot the LHY gene (Alc::LHY) were irrigated with 6% ethanol at ZT 17 (17 hours after dawn). Their transcriptome was compared to that of wild-type plants exposed to the same treatment at times 0, 2, 4 and 8 hours after ethanol addition. Duplicate experiments were carried out for both Alc::LHY and wild-type plants.
2014-10-01 | E-GEOD-48366 | biostudies-arrayexpress
Project description:In order to study possible effects of cryptochrome 2-mediated light signals on the global expression profiles of tomato genes, we performed large scale transcription comparisons in wt and CRY2-OX by using a DNA microarray of more than 90,000 tomato oligo-probes.<br>Tomato plants were grown under a daily light cycle of 16h light/8h darkness (LD) and leaves from both genotypes were sampled at presumptive dawn (Zeitgeber time (ZT) 0), eight hours after dawn (ZT8), at presumptive dusk (ZT16) and four hours after dusk (ZT20).
2011-12-12 | E-MEXP-2278 | biostudies-arrayexpress
Project description:The first described feedback loop of the Arabidopsis circadian clock is based on reciprocal regulation between TOC1 and CCA1/LHY. CCA1 and LHY are MYB transcription factors that bind directly to the TOC1 promoter to negatively regulate its expression. Conversely, the activity of TOC1 has remained less well characterized. Genetic data supports that TOC1 is necessary for the reactivation of CCA1/LHY, but there is little description of its biochemical function. Here we show that TOC1 occupies specific genomic regions in the CCA1 and LHY promoters. Purified TOC1 binds directly to DNA through its CCT domain, which is similar to known DNA binding domains. Chemical induction and transient overexpression of TOC1 in Arabidopsis seedlings cause repression of CCA1/LHY expression demonstrating that TOC1 can repress direct targets, and mutation or deletion of the CCT domain prevents this repression showing that DNA binding is necessary for TOC1 action. Furthermore, we use the Gal4/UAS system in Arabidopsis to show that TOC1 acts as a general transcriptional repressor, and that repression activity is in the Pseudoreceiver (PR) domain of the protein. To identify the genes regulated by TOC1 on a genomic scale, we couple TOC1 chemical induction with microarray analysis and identify new potential TOC1 targets and output pathways. Together these results define the biochemical action of the core clock protein TOC1 and refine our perspective on how plant clocks function. Keywords: Expression profiling by array wild type (Col-0) and ALC::TOC1 were sown on Murashige-Skoog with 0.8% agar, stratified for 48 hours and grown in12:12 light:dark (LD) for 12 days and either left in LD or transferred to constant light (LL) and then grown for one more day before the start of the experiment. Tissue was submerged in Murashige-Skoog media supplemented with 2.5% ethanol or no ethanol (mock) and with 20mM MG132 for 3 hours and harvested at ZT1. Three replicates each of the seedlings were collected and frozen in liquid nitrogen.
2012-01-15 | E-GEOD-34897 | biostudies-arrayexpress
Project description:We assayed the TOM2 microarray with target RNAs extracted from ZT0 (presumptive dawn), ZT8 (eight hours after dawn), ZT16 (presumptive dusk) and ZT20 (four hours after dusk), in Light/Dark (LD) conditions . The experimental design compared three time points to ZT0 used as a common reference: ZT8 vs. ZT0, ZT16 vs. ZT0 and ZT20 vs. ZT0. Sampling time is expressed as hours after dawn (Zeitgeber Time - ZT)
2009-04-02 | E-MEXP-1456 | biostudies-arrayexpress
Project description:The plant circadian enables plants to adjust their physiology and modulate their developmental responses in anticipation of diurnal and seasonal changes in environmental conditions. Thus, it makes an important contribution to overall fitness. The complex regulatory network underlying the oscillatory mechanism of the clock is now well characterised, but we still know relatively little about how downstream processes are controlled. In order to investigate this question we identified genes that are under direct control of one of the oscillator components, a MYB transcription factor known as LATE ELONGATED HYPOCOTYL (LHY). 2-week-old wild-type (Ws) and LHY knock-out (lhy-21) seedlings were harvested 2 h after dawn. Tissue was cross-linked using 1% formaldehyde for 10 min. Chromatin was extracted and used for immunoprecipitation using an antibody to the full-length LHY protein. The immunoprecipitated DNA was sequenced using Illumina technology. LHY binding regions were identified as genomic regions that showed over-representation of reads in the wild-type sample as compared to the LHY knock-out sample.
2014-03-01 | E-GEOD-52175 | biostudies-arrayexpress
Project description:Circadian rhythmicity in renal function suggests a requirement for circadian adaptations in renal metabolism. We studied circadian changes in renal metabolic pathways using integrated transcriptomic, proteomic and metabolomic analysis performed on control mice and mice deficient in the circadian clock gene Bmal1 in the renal tubule (cKOt mice). Proteins were extracted from whole kidneys of 60 mice. Of these, 30 were conditional knockouts of Arntl (Bmal1) and 30 were of control genotype. They were housed under 12-hours light/12-hours dark cycles and were sacrificed at six different time points: zeitgeber time ZT 0, ZT 4, ZT 8, ZT 12, ZT 16, ZT 20 ( ZT 0 being the time of light on and ZT 12 the time of light off). Five replicates per genotype and time point were analysed.
2023-03-15 | PXD036803 | Pride
Project description:Transcriptome analysis has revealed a light-regulated WD (tryptophan and aspartate)-containing protein, LWD1. LWD1 and LWD2 share greater than 90% amino acid sequence homology. The lack of phenotype changes in the lwd1 or lwd2 single mutant implies that the proteins function redundantly. The lwd1lwd2 double mutant, however, has an early flowering phenotype under both long-day (LD) and short-day (SD) conditions. Functional complementation experiment revealed that LWDs are indeed responsible for the defect in photoperiod sensing in lwd1lwd2 double mutant plants. The expression of LWD1 exhibits a diurnal pattern and peaks before dawn. The period length of oscillator (CCA1, LHY, TOC1 and ELF4) and output (CCR2 and CAB2) genes in the lwd1lwd2 double mutant is significantly shorter than that in wild-type Arabidopsis under free running condition. Under entrainment conditions, the expression phase of oscillator (CCA1, LHY, TOC1 and ELF4) and output (GI, FKF1, CDF1, CO and FT) genes shifts ~3 hr forward in the lwd1lwd2 double mutant. Our data indicated that the early flowering phenotype in lwd1lwd2 plants is contributed by the significant phase shift of CO and, therefore, an increased expression of FT before dusk under SD conditions. Our data imply that LWD1/LWD2 proteins function in close proximity to the circadian oscillators for the regulation of photoperiod sensing.
2008-10-08 | GSE11762 | GEO
Project description:The goal of this study is to obtain genome-wide shade-responsive genes in adult plant. We grew plants under long-day condition with high R/FR ratio (simulated "sun" condition) for two weeks. Plants were treated with shade starting at ZT 4 or left in the sun. We prepared two replicates of each sample at 1 hour and 4 hours after sun and shade treatment and five plants were pooled for each replicate. Cotyledons, hypocotyls, and roots were removed from the samples, leaving leaves and apical tissue.
2015-03-18 | GSE66967 | GEO
Project description:Transcriptome analysis has revealed a light-regulated WD (tryptophan and aspartate)-containing protein, LWD1. LWD1 and LWD2 share greater than 90% amino acid sequence homology. The lack of phenotype changes in the lwd1 or lwd2 single mutant implies that the proteins function redundantly. The lwd1lwd2 double mutant, however, has an early flowering phenotype under both long-day (LD) and short-day (SD) conditions. Functional complementation experiment revealed that LWDs are indeed responsible for the defect in photoperiod sensing in lwd1lwd2 double mutant plants. The expression of LWD1 exhibits a diurnal pattern and peaks before dawn. The period length of oscillator (CCA1, LHY, TOC1 and ELF4) and output (CCR2 and CAB2) genes in the lwd1lwd2 double mutant is significantly shorter than that in wild-type Arabidopsis under free running condition. Under entrainment conditions, the expression phase of oscillator (CCA1, LHY, TOC1 and ELF4) and output (GI, FKF1, CDF1, CO and FT) genes shifts ~3 hr forward in the lwd1lwd2 double mutant. Our data indicated that the early flowering phenotype in lwd1lwd2 plants is contributed by the significant phase shift of CO and, therefore, an increased expression of FT before dusk under SD conditions. Our data imply that LWD1/LWD2 proteins function in close proximity to the circadian oscillators for the regulation of photoperiod sensing. Experiment Overall Design: Two biological replicates were performed to examine the differential gene expression between wild-type and lwd1lwd2 double mutant. The plants were grown under 12 h L/ 12 h D for 31 days before harvesting their above ground tissues at ZT5-9.
2008-10-26 | E-GEOD-11762 | biostudies-arrayexpress
Project description:Anopheles gambiae, the primary African malarial mosquito, exhibits numerous behaviors that are under diel and circadian control, including locomotor activity, swarming, mating, host seeking, eclosion, egg laying and sugar feeding. However, little has been performed to elucidate the molecular basis for these daily rhythms. To study how gene expression is globally regulated by diel and circadian mechanisms, we have undertaken a DNA microarray analysis of A. gambiae head and bodies under 12:12 light:dark cycle (LD) and constant dark (DD, free-running) conditions. Zeitgeber Time (ZT) with ZT12 defined as time of lights OFF under the light:dark cycle, and ZT0 defined as end of the dawn transition. Circadian Time (CT) with CT0 defined as subjective dawn, inferred from ZT0 of the previous light:dark cycle.
2011-06-29 | GSE22585 | GEO