Rewiring of liver diurnal transcriptome rhythms by triiodothyronine (T3) supplementation
- University of Lübeck, Germany
- Karolinska Institute, Sweden
- University of Sao Paulo, Brazil
- Queensland University of Technology, Australia
- University Hospital Schleswig-Holstein, Germany
- University of Queensland, Australia
Abstract
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.
Data availability
All experimental data was deposited in the Figshare depository (https://doi.org/10.6084/m9.figshare.20376444.v1). Microarray data was deposited in the Gene Expression Omnibus (GEO) database under access code GSE199998 (https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE199998)
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Rewiring of liver diurnal transcriptome rhythms by triiodothyronine (T3) supplementationGene Expression Omnibus, GSE199998.
Article and author information
Author details
Leonardo VM de Assis
Funding
Deutsche Forschungsgemeinschaft (353-10/1; GRK-1957; CRC-296 LocoTact"")
- Henrik Oster
Deutsche Forschungsgemeinschaft (CRC-296 LocoTact" (TP14).")
- Jens Mittag
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2022, de Assis et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Rewiring of liver diurnal transcriptome rhythms by triiodothyronine (T3) supplementation
eLife 11:e79405.
https://doi.org/10.7554/eLife.79405
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