The PAR-domain basic leucine zipper (PAR bZip) transcription factors DBP, TEF, and HLF accumulate in a highly circadian manner in several peripheral tissues, including liver and kidney. Mice devoid of all three of these proteins are born at expected Mendelian ratios, but are epilepsy-prone, age at an accelerated rate and die prematurely. In the hope of identifying PAR bZip target genes whose altered expression might contribute to the high morbidity and mortality of PAR bZip triple knockout mice, we compared the liver and kidney transcriptomes of these animals to those of wild-type or heterozygous mutant mice. These experiments revealed that PAR bZip proteins control the expression of many enzymes and regulators involved in detoxification and drug metabolism, such as cytochrome P450 enzymes, carboxylesterases, and constitutive androstane receptor (CAR). Indeed, PAR bZip triple knockout mice are hypersensitive to xenobiotic compounds, and the deficiency in detoxification may contribute to their early ageing.
The circadian PAR-domain basic leucine zipper transcription factors DBP, TEF, and HLF modulate basal and inducible xenobiotic detoxification.
Sex, Specimen part, Time
View SamplesIn mammals body temperature fluctuates diurnally around a mean value of 36-37°C. Despite the small differences between minimal and maximal values, body temperature rhythms can drive robust cycles in gene expression in cultured cells and, likely, in, animals. Here we studied the mechanisms responsible for the temperature-dependent expression of Cold- Inducible RNA-Binding Protein (CIRBP). In NIH3T3 fibroblasts exposed to simulated mouse body temperature cycles Cirbp mRNA oscillates about 3-fold in abundance, as it does in mouse liver. This daily mRNA accumulation cycle is directly controlled by temperature oscillations and does not depend on the cells’ circadian clocks. Here, we show that the temperature-dependent accumulation of Cirbp mRNA is controlled primarily by the regulation of splicing efficiency, defined as the fraction of Cirbp pre-mRNA processed into mature mRNA. As revealed by genome-wide “approach-to-steady-kinetics”, this posttranscriptional mechanism is wide-spread in the temperature-dependent control of gene expression. Overall design: Cultured NIH3T3 cells seeded and kept at 37C degree for 4 hours before being switched to 33C and 38C. After 16 hours of incubation the temperature was shifted to 38C and 33C, respectively. Sample were then taken at 0, 1, 3, 6 and 9 hour after the temperature shift. Paired-end, strand-specific, total RNA-seq was performed over the samples at the respective time points using the Illumina HiSeq2500 platform.
Temperature regulates splicing efficiency of the cold-inducible RNA-binding protein gene Cirbp.
Specimen part, Subject, Time
View SamplesDiurnal oscillations of gene expression are a hallmark of rhythmic physiology across most living organisms. Such oscillations are controlled by the interplay between the circadian clock and feeding rhythms. While rhythmic mRNA accumulation has been extensively studied, comparatively less is known about their transcription and translation. Here, we quantified simultaneously temporal transcription, accumulation, and translation of mouse liver mRNAs under physiological light-dark conditions and ad libitum or night-restricted feeding in wild-type and Bmal1 deficient animals. We found that rhythmic transcription predominantly drives rhythmic mRNA accumulation and translation for a majority of genes. Comparison of wild-type and Bmal1 KO mice shows that circadian clock and feeding rhythms have broad impact on rhythmic genes expression, Bmal1 deletion having surprisingly more impact at the post-transcriptional level. Translation efficiency is differentially regulated during the diurnal cycle for genes with 5'-TOP sequences and for genes involved in mitochondrial activity and harboring a TISU motif. The increased translation efficiency of 5'-TOP and TISU genes is mainly driven by feeding rhythms but Bmal1 deletion impacts also amplitude and phase of translation, including TISU genes. Together this study emphasizes the complex interconnections between circadian and feeding rhythms at several steps ultimately determining rhythmic gene expression and translation. Overall design: RNA-Seq from total RNA of mouse liver during the dirunal cycle. Time-series mRNA profiles of wild type (WT) and Bmal -/- mice under ad libitum and night restriced feeding regimen were generated by deep sequencing.
Diurnal Oscillations in Liver Mass and Cell Size Accompany Ribosome Assembly Cycles.
Cell line, Subject
View SamplesMammalian gene expression displays widespread circadian oscillations. Rhythmic transcription underlies the core clock mechanism, but it cannot explain numerous observations made at the level of protein rhythmicity. We have used ribosome profiling in mouse liver to measure the translation of mRNAs into protein around-the-clock and at high temporal and nucleotide resolution. Transcriptome-wide, we discovered extensive rhythms in ribosome occupancy, and identified a core set of ˜150 mRNAs subject to particularly robust daily changes in translation efficiency. Cycling proteins produced from non-oscillating transcripts revealed thus far unknown rhythmic regulation associated with specific pathways (notably in iron metabolism, through the rhythmic translation of transcripts containing iron responsive elements), and indicated feedback to the rhythmic transcriptome through novel rhythmic transcription factors. Moreover, estimates of relative levels of core clock protein biosynthesis that we deduced from the data explained known features of the circadian clock better than did mRNA expression alone. Finally, we identified uORF translation as a novel regulatory mechanism within the clock circuitry. Consistent with the occurrence of translated uORFs in several core clock transcripts, loss-of-function of Denr, a known regulator of re-initiation after uORF usage and of ribosome recycling, led to circadian period shortening in cells. In summary, our data offer a framework for understanding the dynamics of translational regulation, circadian gene expression, and metabolic control in a solid mammalian organ. Overall design: A total of 48 mice were entrained under 12hours light:dark conditions for 2 weeks and also collected under 12hours light:dark. Mice were sacrificed every two hours during the 24 hours daily cycle. Two replicates per time point, each replicate is a pool of 2 livers.
Diurnal Oscillations in Liver Mass and Cell Size Accompany Ribosome Assembly Cycles.
No sample metadata fields
View SamplesUsp22, a component of the SAGA complex, is over expressed in highly aggressive cancers, but the normal functions of this deubiquitinase are not well defined. We determined that loss of Usp22 in mice results in embryonic lethality due to defects in extra-embryonic placental tissues and failure to establish proper vascular interactions with the maternal circulatory system. These phenotypes arise from abnormal gene expression patterns that reflect defective kinase signaling, including TGFß and several receptor tyrosine kinase (RTK) pathways. Usp22 deletion in endothelial cells and pericytes induced from embryonic stem cells also hinders these signaling cascades with detrimental effects on cell survival and differentiation as well as ability to form vessels. Our findings provide new insights to Usp22 functions during development that may offer clues to its role in disease states. Overall design: To determine changes in gene expression profile upon Usp22 loss in the developing placenta, RNA from day E9.5 placentas from wild-type and Ups22-/- mice s was isolated for deep sequencing, in triplicates and duplicates respectively. Key genes identified from RNAseq were validated by qRT-PCR using RNA from the same samples that were used for sequencing.
USP22 controls multiple signaling pathways that are essential for vasculature formation in the mouse placenta.
Cell line, Subject
View SamplesTo identify the target genes of Runx1/Cbfb in MLL fusion leukemia, we performed microarray analysis using control and Runx1/Cbfb-deleted MLL-AF9 cells.
Transcription factor RUNX1 promotes survival of acute myeloid leukemia cells.
No sample metadata fields
View SamplesTo identify the target genes of Runx1 in MLL fusion leukemia, we performed microarray analysis using control and Runx1-deficient MLL-ENL leukemia cells.
Transcription factor RUNX1 promotes survival of acute myeloid leukemia cells.
No sample metadata fields
View SamplesThis study is a follow-up to GSE35790.
Transcriptional regulatory logic of the diurnal cycle in the mouse liver.
Sex, Specimen part, Time
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Genome-wide RNA polymerase II profiles and RNA accumulation reveal kinetics of transcription and associated epigenetic changes during diurnal cycles.
Specimen part
View SamplesCyclic regulatory systems are ubiquitous in cells and tissues. In the liver rhythms in mRNA expression are determined by the homeostatic regulation that operates on daily circumstances. In particular the specific response to nutrients, as well as systemic and peripheral circadian oscillators, contribute to the set up of the hepatic homeostasis at different phases of the day. In this series we used microarrays to detail the global program of gene expression in the mouse liver under physiological daily variations, determined by both the feeding and the circadian cycles.
Genome-wide RNA polymerase II profiles and RNA accumulation reveal kinetics of transcription and associated epigenetic changes during diurnal cycles.
Specimen part
View Samples