Circadian clock regulation by compartmentalized protein translation
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA922087 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Cells exquisitely compartmentalize many biochemical reactions through phase-separated membrane-less organelles. Besides spatial organization, many biological processes are temporally regulated. While both transcription and translation oscillate in a rhythmic manner, the regulatory mechanism of the latter is understudied. Here we report that the translational regulation during circadian cycles is associated with oscillating phase separation controlled by Ataxin-2 and Ataxin-2L. Ataxin-2/2L forms rhythmic condensates through phase separation in the mammalian central clock suprachiasmatic nucleus to selectively concentrate the transcripts of the core clock genes and recruit the mRNA translation machinery. The rhythmic translational activation is abolished in cells and mouse circadian behavior is altered in the absence of Ataxin-2/2L. During aging or neurodegeneration, Ataxin-2/2L form large, irreversible puncta that no longer regulate translation. Overall, our results unveil Ataxin-2/2L’s role as the master regulators of rhythmic translation via a oscillating phase-separation, and explained the reason for their dysfunction in disease states.
2023-06-24 | GSE222433 | GEO
Project description:Evolutionary conserved biological rhythms play a fundamental role in the physiology and behavior of all light-sensitive organisms. Generation of rhythmic expression of clock-controlled genes is orchestrated by a molecular circadian clock constitutes by interconnected negative feedback loops of transcription factors. In this study, we want to characterize gene which also present a rhythmic translation through the characterization of genes with a rhythmic polysomal/total RNA ratio. Analyze of gene expression in liver total RNA and polysomal RNA harvested every 2 hrs during 2 series of 48 hrs, 2 mice per samples
2012-12-01 | E-GEOD-33726 | biostudies-arrayexpress
Project description:Circadian rhythms are a series of endogenous autonomous 24-hour oscillations generated by the circadian clock. At the molecular level, the circadian clock is generated by a transcription-translation feedback loop, where BMAL1 and CLOCK transcription factors of the positive arm activate the expression of CRYPTOCHROME and PERIOD (PER) genes of the negative arm as well as the circadian clock-regulated genes. In this project, we aimed at finding the interactome of PER2 protein in human U2OS osteosarcoma cell line using proximity-dependent biotin identification (BioID) technique. U2OS clones overexpressing PER2-BioID2 or BioID2 were treated with dexamethasone in order to reset the circadian rhythm, and cells were then incubated in biotin-containing media for 12 hours to label the proteins in close proximity of PER2-BioID2. Samples were collected after 36 and 48 hours of the resetting to identify the labeled proteins by mass spectrometry. In addition to known interactors such as CRY1 and CRY2, many novel interactors were identified. In summary, we obtained a network of PER2 interactome and confirmed some of the novel interactions using classical the co-immunoprecipitation method.
2022-04-22 | PXD025179 | Pride
Project description:The non-canonical initiation factor DENR promotes translation reinitiation on uORF-containing mRNAs. Moreover, DENR depletion shortens circadian period in mouse fibroblasts, suggesting that uORF usage and reinitiation regulate clock function. To identify DENR-regulated translation events transcriptome-wide and, in particular, specific core clock transcripts affected by this mechanism, we have used ribosome profiling in DENR-deficient NIH3T3 cells. We found 240 transcripts with altered translation rate, and used linear regression analysis to extract uORF features predictive of DENR dependance. Among core clock genes, we identified Clock as a DENR target. Using Clock 5'UTR mutants, we mapped the specific uORF through which DENR acts to regulate CLOCK protein biosynthesis. Notably, these experiments identified an alternative downstream start codon, which likely represents the true CLOCK N-terminus. Our findings provide insights into uORF-mediated translational regulation that can regulate the mammalian circadian clock and gene expression at large.
2019-04-01 | GSE116221 | GEO
Project description:The non-canonical initiation factor DENR promotes translation reinitiation on uORF-containing mRNAs. Moreover, DENR depletion shortens circadian period in mouse fibroblasts, suggesting that uORF usage and reinitiation regulate clock function. To identify DENR-regulated translation events transcriptome-wide and, in particular, specific core clock transcripts affected by this mechanism, we have used ribosome profiling in DENR-deficient NIH3T3 cells. We found 240 transcripts with altered translation rate, and used linear regression analysis to extract uORF features predictive of DENR dependance. Among core clock genes, we identified Clock as a DENR target. Using Clock 5'UTR mutants, we mapped the specific uORF through which DENR acts to regulate CLOCK protein biosynthesis. Notably, these experiments identified an alternative downstream start codon, which likely represents the true CLOCK N-terminus. Our findings provide insights into uORF-mediated translational regulation that can regulate the mammalian circadian clock and gene expression at large.
2019-04-01 | GSE124790 | GEO
Project description:Mammalian 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.
2015-10-14 | GSE67305 | GEO
Project description:Oscillatory lysosomal activity for disposal of the components of the cellular clock is essential to sustain organismal circadian rhythms
2021-10-05 | PXD019704 | Pride
Project description:Proteins destined for secretion move from the endoplasmic reticulum (ER, the site of synthesis) to Golgi cisternae then onto the cell surface in transport vesicles. Although the mechanism of anterograde and retrograde transport via vesicles is well understood the temporal coordination of transport between organelles has not been studied. Here we show that the extracellular levels of collagen-I (the most abundant protein in vertebrates) are 24-h rhythmic in tendon, which is the richest source of collagen-I. Rhythmicity is the result of circadian clock control of the secretory pathway via ER-ribosome docking, Tango1-dependent ER export, phosphodiesterase-dependent Golgi-ER retrograde transport of Hsp47 (a collagen molecular chaperone), and Vps33b-dependent post Golgi export, which pause collagen-I transport at each node in the pathway during a 24-hour cycle. The structure and mechanical properties of tendon are also 24-hourly rhythmic. Thus, the circadian clock is a master logistic operator of the secretory pathway in mammalian cells.
2019-10-28 | PXD013450 | Pride
Project description:The circadian clock is comprised of proteins that form negative feedback loops, which regulate the timing of global gene expression in a coordinated 24 hour cycle. As a result, the plant circadian clock is responsible for regulating numerous physiological processes central to growth and survival. To date, most plant circadian clock studies have relied on diurnal transcriptome changes to elucidate molecular connections between the circadian clock and observable phenotypes in wild-type plants. Here, we have combined high-throughput RNA-sequencing and mass spectrometry to comparatively characterize the lhycca1, prr7prr9, gi and toc1 circadian clock mutant rosette transcriptome and proteome at the end-of-day and end-of-night.
2018-01-02 | PXD004763 | Pride
Project description:Recent reports indicate hypoxia influences the clock through the transcriptional activities of hypoxia inducible factors (HIFs) at clock genes. Unexpectedly, we uncover a profound disruption of the circadian clock and diurnal transcriptome when hypoxic cells are permitted to acidify, recapitulating the tumor microenvironment. Buffering against acidification or inhibiting lactic acid production fully rescues circadian oscillation. Acidification of several human and murine cell lines, as well as primary murine T cells, suppresses mechanistic target of rapamycin complex 1 (mTORc1) signaling, a key regulator of translation in response to metabolic status. We find acid drives peripheral redistribution of normally perinuclear lysosomes, inhibiting lysosome-bound mTOR. Restoring mTORc1 signaling and the translation it governs rescues clock oscillation, revealing a model in which lactic acid produced during the cellular metabolic response to hypoxia suppresses the circadian clock through diminished translation of clock constituents.
2018-06-02 | GSE101988 | GEO