Light/dark- and temperature-regulated transcriptional rhythms in adult Caenorhabditis elegans
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ABSTRACT:
ORGANISM(S): Caenorhabditis elegans
PROVIDER: GSE23528 | GEO | 2010/09/01
SECONDARY ACCESSION(S): PRJNA131785
REPOSITORIES: GEO
Similar Datasets
Project description:Most organisms have an endogenous circadian clock that is synchronized to environmental signals such as light and temperature. Although circadian rhythms have been described in the nematode C. elegans at the behavioral level, these rhythms appear to be relatively non-robust. Moreover, in contrast to other animal models, no circadian transcriptional rhythms have been identified. Thus, whether this simple nematode contains a bona fide circadian clock remains an open question. We used microarray experiments to identify light- and temperature-regulated transcriptional rhythms in C. elegans, and show that subsets of these transcripts are regulated in a circadian manner. In addition, we find that light and temperature also globally drive the expression of many genes, indicating that C. elegans exhibits systemic responses to these stimuli. Populations of growth-synchronized wild-type C. elegans L1 larvae were entrained for 5 days until adulthood to 12:12 hr light/dark (LD) cycles (500-1000 lux) at a constant temperature of 18°C, or for 4 days to 12:12 hr temperature cycles (25:15°C - warm/cold or WC) in constant darkness. RNA was collected every 4 hrs during the last entrainment and the subsequent free-running days and analyzed via hybridization of Affymetrix GeneChips. L4 larvae were transferred to FUDR-containing plates to inhibit embryonic development.
2010-08-31 | E-GEOD-23528 | biostudies-arrayexpress
Project description:Recent evidence suggest that the circadian timing system plays an important role in the control of renal function and maintaining blood pressure. Here, we analyzed circadian rhythms of urinary excretion of sodium and potassium in wild-type mice and mice lacking circadian transcriptional activator clock. Analysis of urines collected at hourly intervals over a 24-hour period revealed dramatic changes in rhythms of sodium and potassium excretion in clock(-/-) mice. In parallel, significant differences in circadian pattern of plasma aldosterone levels, but not in the 24-hour mean aldosterone levels, were observed. Microarray-based profiling of renal transcriptomes demonstrated that clock(-/-) mice exhibit dysregulation in multiple mechanisms involved in maintaining sodium and potassium balance by the kidney. The most significant changes were detected in the expression levels of several key enzymes (Cyp4a14, Cyp4a12a and Cyp4a12b) required for the conversion of arachidonic acid to 20-hydroxyeicosatetraenoic acid (20-HETE), a powerful regulator of renal sodium and potassium excretion, renal vascular tone and blood pressure. The 20-HETE levels measured in kidney microsomes of wild-type mice followed a circadian-like temporal pattern. In clock(-/-) mice, the acrophase of this rhythm was shifted by 8 hours and the 24-hour mean levels of 20-HETE were significantly decreased. These results demonstrate that circadian rhythms of urine electrolyte excretion are largely dependent on the circadian clock activity and indicate that circadian oscillations in renal 20-HETE content could be an important mechanism of blood pressure regulation. We examined the temporal profiles of gene expression in mouse whole kidney. Animals were sacrificed for microdissection every 4 hours, i.e. at ZT0, ZT4, ZT8, ZT12, ZT16 and ZT20 (ZT M-bM-^@M-^S Zeitgeber (circadian) time, indicates time of light-on as ZT0 and time of light-off as ZT12). The microarray hybridization was performed in duplicates on pools of RNA composed of equivalent amounts of RNA prepared from teo or three animals at each ZT time-point.
2012-04-29 | E-GEOD-27366 | biostudies-arrayexpress
Project description:Renal excretion of water and major electrolytes exhibits a significant circadian rhythm. This functional periodicity is believed to result, at least in part, from circadian changes in secretion/reabsorption capacities of the distal nephron and collecting ducts. Here, we studied the molecular mechanisms underlying circadian rhythms in the distal nephron segments, i.e. distal convoluted tubule (DCT) and connecting tubule (CNT) and, the cortical collecting duct (CCD). Temporal expression analysis performed on microdissected mouse DCT/CNT or CCD revealed a marked circadian rhythmicity in the expression of a large number of genes crucially involved in various homeostatic functions of the kidney. This analysis also revealed that both DCT/CNT and CCD possess an intrinsic circadian timing system characterized by robust oscillations in the expression of circadian core clock genes (clock, bma11, npas2, per, cry, nr1d1) and clock-controlled Par bZip transcriptional factors dbp, hlf and tef. The clock knockout mice or mice devoid of dbp/hlf/tef (triple knockout) exhibit significant changes in renal expression of several key regulators of water or sodium balance (vasopressin V2 receptor, aquaporin-2, aquaporin-4, M-oM-^AM-!ENaC). Functionally, the loss of clock leads to a complex phenotype characterized by partial diabetes insipidus, dysregulation of sodium excretion rhythms and a significant decrease in blood pressure. Collectively, this study uncovers a major role of molecular clock in renal function. Experiment Overall Design: We examined the temporal profiles of gene expression in mouse distal nephron segments and collecting ducts. The RNA was extracted from microdissected distal convoluted tubules and connecting tubules (DCT/CNT samples) or, cortical collecting ducts (CCD samples). Animals were sacrificed for microdissection every 4 hours, i.e. at ZT0, ZT4, ZT8, ZT12, ZT16 and ZT20 (ZT M-bM-^@M-^S Zeitgeber (circadian) time, indicates time of light-on as ZT0 and time of light-off as ZT12). The microarray hybridization was performed in duplicates on two pools of RNA composed of equivalent amounts of RNA prepared from five animals at each ZT time-point.
2009-10-30 | E-GEOD-17739 | biostudies-arrayexpress
Project description:Circadian rhythms are responsive to a variety of external cues, light and metabolism being the most important. In mammals, the light signal is sensed by the retina and transmitted to the SCN master clock, where it is translated into the molecular oscillator via regulation of clock gene transcription. The signalling pathways governing the molecular translation from metabolic signals to circadian output in peripheral oscillators, in contrast, are less understood. FOXO transcription factors are known to translate external metabolic cues to internal transcriptional programs. In the past couple of years it has become evident that both FOXO transcription factors and the circadian clock are of key importance in the underlying mechanisms of ageing and the regulation of metabolism. We now show FOXO3 to be a crucial modulator of circadian rhythmicity via direct transcriptional regulation of Clock, a core component of the molecular oscillator, and identify FOXO3 as a novel link in the circadian feedback loop, which is required for circadian rhythms in liver. We propose that FOXO3 directly feeds back into the circadian oscillator in response to metabolic cues.
2014-06-03 | GSE41555 | GEO
Project description:Circadian rhythms are responsive to a variety of external cues, light and metabolism being the most important. In mammals, the light signal is sensed by the retina and transmitted to the SCN master clock, where it is translated into the molecular oscillator via regulation of clock gene transcription. The signalling pathways governing the molecular translation from metabolic signals to circadian output in peripheral oscillators, in contrast, are less understood. FOXO transcription factors are known to translate external metabolic cues to internal transcriptional programs. In the past couple of years it has become evident that both FOXO transcription factors and the circadian clock are of key importance in the underlying mechanisms of ageing and the regulation of metabolism. We now show FOXO3 to be a crucial modulator of circadian rhythmicity via direct transcriptional regulation of Clock, a core component of the molecular oscillator, and identify FOXO3 as a novel link in the circadian feedback loop, which is required for circadian rhythms in liver. We propose that FOXO3 directly feeds back into the circadian oscillator in response to metabolic cues.
2014-06-03 | GSE41554 | GEO
Project description:Circadian (~24 hour) clocks exist in almost all types of living organism and play a fundamental role in regulating daily physiological and behavioural processes. The transcription factor BMAL1 (ARNTL) is thought to be one of the principal drivers of the molecular clock in mammals since its deletion abolishes 24-hour activity patterning, an important physiological output of the clockwork. However, whether or not Bmal1-/- mice can nevertheless display molecular 24-hour rhythms is unknown. Here, we determined whether Bmal1 function is necessary for daily molecular oscillations in two tissues – skin fibroblasts and liver. Unexpectedly, both tissues exhibited robust 24-hour oscillations over 2-3 days in the absence of any exogenous synchronizers such as daily light or temperature cycles. This demonstrates a competent 24-hour molecular pacemaker in Bmal1 knockouts. Indeed, molecular oscillations were pervasive throughout the transcriptome, proteome and phosphoproteome of Bmal1-/- mice. In particular, several proteins exhibited rhythmic phosphorylation in both Bmal1-proficient and -deficient cells, highlighting an unanticipated role for post-translational regulators in 24-hour rhythms in the absence of any known clock mechanisms.
2020-02-17 | PXD009243 | Pride
Project description:Circadian rhythms are responsive to a variety of external cues, light and metabolism being the most important. In mammals, the light signal is sensed by the retina and transmitted to the SCN master clock, where it is translated into the molecular oscillator via regulation of clock gene transcription. The signalling pathways governing the molecular translation from metabolic signals to circadian output in peripheral oscillators, in contrast, are less understood. FOXO transcription factors are known to translate external metabolic cues to internal transcriptional programs. In the past couple of years it has become evident that both FOXO transcription factors and the circadian clock are of key importance in the underlying mechanisms of ageing and the regulation of metabolism. We now show FOXO3 to be a crucial modulator of circadian rhythmicity via direct transcriptional regulation of Clock, a core component of the molecular oscillator, and identify FOXO3 as a novel link in the circadian feedback loop, which is required for circadian rhythms in liver. We propose that FOXO3 directly feeds back into the circadian oscillator in response to metabolic cues. We performed a microarray study on synchronized NIH 3T3 cells upon transient overexpression of FoxO6 (oeO6). Cells were harvested for RNA isolation 24h (time1), 30h(time2), 36h(time3) and 42h(time4) after synchronization. Experimental samples were hybridized against a reference pool of cRNA, which was derived from unsynchronized NIH 3T3 cells. Experiments were performed 4 times, of each sample group two samples were labeled with cy5 and co-hybridized with reference RNA labeled with cy3, and two samples were labeled and hybridized in the opposite way. Microarrays used were Mouse Whole Genome Gene Expression Microarrays V1 (Agilent Technologies, Belgium)
2014-06-03 | E-GEOD-41554 | biostudies-arrayexpress
Project description:Circadian profiling was performed in mouse livers from three different genotypes/treatments: Wildtype, Clock mutant, and brain-specific Clock rescue. Rescuing Clock specifically in the brain partially rescued robust circadian and harmonic rhythms.
2012-06-01 | GSE30411 | GEO
Project description:Diurnal (i.e., 24-hour) physiological rhythms depend on transcriptional programs controlled by a set of circadian clock genes/proteins. Systemic factors like humoral and neuronal signals, oscillations in body temperature, and food intake align physiological circadian rhythms with external time. Thyroid hormones (THs) are major regulators of circadian clock target processes such as energy metabolism, but little is known about how fluctuations in TH levels affect the circadian coordination of tissue physiology. In this study, a high triiodothyronine (T3) state was induced in mice by supplementing T3 in the drinking water, which affected body temperature, and oxygen consumption in a time-of-day dependent manner. 24-hour transcriptome profiling of liver tissue identified 37 robustly and time independently T3 associated transcripts as potential TH state markers in the liver. Such genes participated in xenobiotic transport, lipid and xenobiotic metabolism. We also identified 10 – 15 % of the liver transcriptome as rhythmic in control and T3 groups, but only 4 % of the liver transcriptome (1,033 genes) were rhythmic across both conditions – amongst these several core clock genes. In-depth rhythm analyses showed that most changes in transcript rhythms were related to mesor (50%), followed by amplitude (10%), and phase (10%). Gene set enrichment analysis revealed TH state dependent reorganization of metabolic processes such as lipid and glucose metabolism. At high T3 levels, we observed weakening or loss of rhythmicity for transcripts associated with glucose and fatty acid metabolism, suggesting increased hepatic energy turnover. In sum, we provide evidence that tonic changes in T3 levels restructure the diurnal liver metabolic transcriptome independent of local molecular circadian clocks.
2022-07-26 | GSE199998 | GEO
Project description:The brain’s suprachiasmatic nucleus (SCN) is the master clock driving circadian rhythms in mammals. Vasoactive intestinal polypeptide (VIP) and its cognate receptor, VPAC2, are expressed in SCN neurons and mice with genetically targeted deletion of VPAC2 (Vipr2 -/-animals) show aberrant resetting to light, abnormal behavioral rhythms, and diminished SCN clock gene expression. Timed daily access to a running-wheel (scheduled voluntary exercise; SVE) promotes Vipr2 -/- SCN clock cell synchrony and 24h behavioral rhythms. We hypothesized that timed exercise alters the SCN transcriptome. Here, in control (Vipr2+/+) and Vipr2-/- mice under freely exercising and SVE conditions, RNAseq and qRT-PCR were used to measured gene expression of laser-dissected SCN. Compared to Vipr2+/+ mice, hundreds of genes were differentially expressed in the SCN from Vipr2-/- mice rhythmic in the freely exercising condition. Unexpectedly, SVE did not promote a Vipr2+/+-like SCN transcriptome in Vipr2-/- mice and many transcripts involved in SCN function including Avp, C1ql3, Gpr176, Prok2, Sst, Per2, and Nr1d1 remained dysregulated in the SVE condition. By contrast, circadian oscillators in the liver and lung were mostly intact in Vipr2-/- mice. This study indicates that marked molecular deficits in the SCN are sustained in behaviorally rhythmic Vipr2-/- mice, raising the possibility that a minimal functional SCN circadian clock can underpin whole animal rhythms.
2023-01-20 | GSE207992 | GEO