ARID1A loss in adult hepatocytes activates β-catenin-mediated erythropoietin transcription
Abstract
Erythropoietin (EPO) is a key regulator of erythropoiesis. The embryonic liver is the main site of erythropoietin synthesis, after which the kidney takes over. The adult liver retains the ability to express EPO, and we discovered here new players of this transcription, distinct from the classical hypoxia-inducible factor pathway. In mice genetically-invalidated in hepatocytes for the chromatin remodeler Arid1a, and for Apc, the major silencer of Wnt pathway, chromatin was more accessible and histone marks turned into active ones at the Epo downstream enhancer. Activating β-catenin signaling increased binding of Tcf4/β-catenin complex and upregulated its enhancer function. The loss of Arid1a together with β-catenin signaling, resulted in cell-autonomous EPO transcription in mouse and human hepatocytes. In mice with Apc-Arid1a gene invalidations in single hepatocytes, Epo de novo synthesis led to its secretion, to splenic erythropoiesis and to dramatic erythrocytosis. Thus, we identified new hepatic EPO regulation mechanism stimulating erythropoiesis.
Data availability
Microarrays have been deposited in GEO database (GSE134553) and are publicly available.All data generated or analysed during this study are included in the manuscript and supporting files. Source data excel files have been provided for Figures 1, 2, 3, 4, 5, 7, 8, 1S1,1S3,3S1,5S1,5S2,7S1.
-
Expression data from isolated areas from [Apc-Arid1a]ko-focal liver tissues after FFPE treatmentNCBI Gene Expression Omnibus, GSE134553.
Article and author information
Author details
Funding
Institut National Du Cancer (Epigenetics and Liver Cancer)
- Rozenn Riou
- Angélique Gougelet
- Cécile Godard
- Julien Calderaro
- Sabine Colnot
Ligue Contre le Cancer (Equipe Labellisée)
- Rozenn Riou
- Angélique Gougelet
- Cécile Godard
- Sabine Colnot
Agence Nationale de la Recherche (Labex Who Am I"; Idex "EpilivCan"")
- Rozenn Riou
- Angélique Gougelet
- Cécile Godard
- Sabine Colnot
Institut National Du Cancer (Chromaliv)
- Rozenn Riou
- Angélique Gougelet
- Cécile Godard
- Sabine Colnot
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study was performed in strict accordance with the French government regulations. All of the animals were handled according to approved institutional animal care and use committee (Ethics Committee of Descartes University, Paris). The protocol was approved by the Ethics Committee of Descartes University, Paris (permit number APAFIS#14472). Every effort was made to minimize suffering.
Copyright
© 2020, Riou 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.
Metrics
-
- 1,427
- views
-
- 207
- downloads
-
- 3
- citations
Views, downloads and citations are aggregated across all versions of this paper published by eLife.
Download links
Downloads (link to download the article as PDF)
Open citations (links to open the citations from this article in various online reference manager services)
Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)
Further reading
-
- Chromosomes and Gene Expression
- Neuroscience
Pathogenic variants in subunits of RNA polymerase (Pol) III cause a spectrum of Polr3-related neurodegenerative diseases including 4H leukodystrophy. Disease onset occurs from infancy to early adulthood and is associated with a variable range and severity of neurological and non-neurological features. The molecular basis of Polr3-related disease pathogenesis is unknown. We developed a postnatal whole-body mouse model expressing pathogenic Polr3a mutations to examine the molecular mechanisms by which reduced Pol III transcription results primarily in central nervous system phenotypes. Polr3a mutant mice exhibit behavioral deficits, cerebral pathology and exocrine pancreatic atrophy. Transcriptome and immunohistochemistry analyses of cerebra during disease progression show a reduction in most Pol III transcripts, induction of innate immune and integrated stress responses and cell-type-specific gene expression changes reflecting neuron and oligodendrocyte loss and microglial activation. Earlier in the disease when integrated stress and innate immune responses are minimally induced, mature tRNA sequencing revealed a global reduction in tRNA levels and an altered tRNA profile but no changes in other Pol III transcripts. Thus, changes in the size and/or composition of the tRNA pool have a causal role in disease initiation. Our findings reveal different tissue- and brain region-specific sensitivities to a defect in Pol III transcription.
-
- Biochemistry and Chemical Biology
- Chromosomes and Gene Expression
The mRNA 5'-cap structure removal by the decapping enzyme DCP2 is a critical step in gene regulation. While DCP2 is the catalytic subunit in the decapping complex, its activity is strongly enhanced by multiple factors, particularly DCP1, which is the major activator in yeast. However, the precise role of DCP1 in metazoans has yet to be fully elucidated. Moreover, in humans, the specific biological functions of the two DCP1 paralogs, DCP1a and DCP1b, remain largely unknown. To investigate the role of human DCP1, we generated cell lines that were deficient in DCP1a, DCP1b, or both to evaluate the importance of DCP1 in the decapping machinery. Our results highlight the importance of human DCP1 in decapping process and show that the EVH1 domain of DCP1 enhances the mRNA-binding affinity of DCP2. Transcriptome and metabolome analyses outline the distinct functions of DCP1a and DCP1b in human cells, regulating specific endogenous mRNA targets and biological processes. Overall, our findings provide insights into the molecular mechanism of human DCP1 in mRNA decapping and shed light on the distinct functions of its paralogs.