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Sarver DC, Garcia-Diaz J, Saqib M, Riddle RC, Wong GW. Tmem263 deletion disrupts the GH/IGF-1 axis and causes dwarfism and impairs skeletal acquisition. eLife 2024; 12:RP90949. [PMID: 38241182 PMCID: PMC10945605 DOI: 10.7554/elife.90949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2024] Open
Abstract
Genome-wide association studies (GWAS) have identified a large number of candidate genes believed to affect longitudinal bone growth and bone mass. One of these candidate genes, TMEM263, encodes a poorly characterized plasma membrane protein. Single nucleotide polymorphisms in TMEM263 are associated with bone mineral density in humans and mutations are associated with dwarfism in chicken and severe skeletal dysplasia in at least one human fetus. Whether this genotype-phenotype relationship is causal, however, remains unclear. Here, we determine whether and how TMEM263 is required for postnatal growth. Deletion of the Tmem263 gene in mice causes severe postnatal growth failure, proportional dwarfism, and impaired skeletal acquisition. Mice lacking Tmem263 show no differences in body weight within the first 2 weeks of postnatal life. However, by P21 there is a dramatic growth deficit due to a disrupted growth hormone (GH)/insulin-like growth factor 1 (IGF-1) axis, which is critical for longitudinal bone growth. Tmem263-null mice have low circulating IGF-1 levels and pronounced reductions in bone mass and growth plate length. The low serum IGF-1 in Tmem263-null mice is associated with reduced hepatic GH receptor (GHR) expression and GH-induced JAK2/STAT5 signaling. A deficit in GH signaling dramatically alters GH-regulated genes and feminizes the liver transcriptome of Tmem263-null male mice, with their expression profile resembling wild-type female, hypophysectomized male, and Stat5b-null male mice. Collectively, our data validates the causal role for Tmem263 in regulating postnatal growth and raises the possibility that rare mutations or variants of TMEM263 may potentially cause GH insensitivity and impair linear growth.
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Affiliation(s)
- Dylan C Sarver
- Department of Physiology, Johns Hopkins University School of MedicineBaltimoreUnited States
| | - Jean Garcia-Diaz
- Department of Orthopaedic Surgery, Johns Hopkins University School of MedicineBaltimoreUnited States
- Department of Orthopaedics, University of Maryland School of MedicineBaltimoreUnited States
- Cell and Molecular Medicine graduate program, Johns Hopkins University School of MedicineBaltimoreUnited States
| | - Muzna Saqib
- Department of Physiology, Johns Hopkins University School of MedicineBaltimoreUnited States
| | - Ryan C Riddle
- Department of Orthopaedic Surgery, Johns Hopkins University School of MedicineBaltimoreUnited States
- Department of Orthopaedics, University of Maryland School of MedicineBaltimoreUnited States
- Research and Development Service, Baltimore Veterans Administration Medical CenterBaltimoreUnited States
| | - G William Wong
- Department of Physiology, Johns Hopkins University School of MedicineBaltimoreUnited States
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2
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Brie B, Sarmento-Cabral A, Pascual F, Cordoba-Chacon J, Kineman RD, Becu-Villalobos D. Modifications of the GH Axis Reveal Unique Sexually Dimorphic Liver Signatures for Lcn13, Asns, Hamp2, Hao2, and Pgc1a. J Endocr Soc 2024; 8:bvae015. [PMID: 38370444 PMCID: PMC10872697 DOI: 10.1210/jendso/bvae015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Indexed: 02/20/2024] Open
Abstract
Growth hormone (GH) modifies liver gene transcription in a sexually dimorphic manner to meet liver metabolic demands related to sex; thus, GH dysregulation leads to sex-biased hepatic disease. We dissected the steps of the GH regulatory cascade modifying GH-dependent genes involved in metabolism, focusing on the male-predominant genes Lcn13, Asns, and Cyp7b1, and the female-predominant genes Hao2, Pgc1a, Hamp2, Cyp2a4, and Cyp2b9. We explored mRNA expression in 2 settings: (i) intact liver GH receptor (GHR) but altered GH and insulin-like growth factor 1 (IGF1) levels (NeuroDrd2KO, HiGH, aHepIGF1kd, and STAT5bCA mouse lines); and (ii) liver loss of GHR, with or without STAT5b reconstitution (aHepGHRkd, and aHepGHRkd + STAT5bCA). Lcn13 was downregulated in males in most models, while Asns and Cyp7b1 were decreased in males by low GH levels or action, or constant GH levels, but unexpectedly upregulated in both sexes by the loss of liver Igf1 or constitutive Stat5b expression. Hao, Cyp2a4, and Cyp2b9 were generally decreased in female mice with low GH levels or action (NeuroDrd2KO and/or aHepGHRkd mice) and increased in HiGH females, while in contrast, Pgc1a was increased in female NeuroDrd2KO but decreased in STAT5bCA and aHepIGF1kd females. Bioinformatic analysis of RNAseq from aHepGHRkd livers stressed the greater impact of GHR loss on wide gene expression in males and highlighted that GH modifies almost completely different gene signatures in each sex. Concordantly, we show that altering different steps of the GH cascade in the liver modified liver expression of Lcn13, Asns, Cyp7b1, Hao2, Hamp2, Pgc1a, Cyp2a4, and Cyp2b9 in a sex- and gene-specific manner.
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Affiliation(s)
- Belen Brie
- Instituto de Biología y Medicina Experimental (IBYME), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), 1428 Ciudad de Buenos Aires, Argentina
| | - Andre Sarmento-Cabral
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Florencia Pascual
- Instituto de Biología y Medicina Experimental (IBYME), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), 1428 Ciudad de Buenos Aires, Argentina
| | - Jose Cordoba-Chacon
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Illinois at Chicago, Chicago, IL 60612, USA
| | - Rhonda Denise Kineman
- Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Illinois at Chicago, Chicago, IL 60612, USA
- Research and Development Division, Jesse Brown Veterans Affairs Medical Center, Chicago, IL 60612, USA
| | - Damasia Becu-Villalobos
- Instituto de Biología y Medicina Experimental (IBYME), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), 1428 Ciudad de Buenos Aires, Argentina
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3
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Rampersaud A, Connerney J, Waxman DJ. Plasma growth hormone pulses induce male-biased pulsatile chromatin opening and epigenetic regulation in adult mouse liver. eLife 2023; 12:RP91367. [PMID: 38091606 PMCID: PMC10721219 DOI: 10.7554/elife.91367] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2023] Open
Abstract
Sex differences in plasma growth hormone (GH) profiles, pulsatile in males and persistent in females, regulate sex differences in hepatic STAT5 activation linked to sex differences in gene expression and liver disease susceptibility, but little is understood about the fundamental underlying, GH pattern-dependent regulatory mechanisms. Here, DNase-I hypersensitivity site (DHS) analysis of liver chromatin accessibility in a cohort of 18 individual male mice established that the endogenous male rhythm of plasma GH pulse-stimulated liver STAT5 activation induces dynamic, repeated cycles of chromatin opening and closing at several thousand liver DHS and comprises a novel mechanism conferring male bias to liver chromatin accessibility. Strikingly, a single physiological replacement dose of GH given to hypophysectomized male mice restored, within 30 min, liver STAT5 activity and chromatin accessibility at 83% of the dynamic, pituitary hormone-dependent male-biased DHS. Sex-dependent transcription factor binding patterns and chromatin state analysis identified key genomic and epigenetic features distinguishing this dynamic, STAT5-driven mechanism of male-biased chromatin opening from a second GH-dependent mechanism operative at static male-biased DHS, which are constitutively open in male liver. Dynamic but not static male-biased DHS adopt a bivalent-like epigenetic state in female liver, as do static female-biased DHS in male liver, albeit using distinct repressive histone marks in each sex, namely, H3K9me3 at male-biased DHS in female liver and H3K27me3 at female-biased DHS in male liver. Moreover, sex-biased H3K36me3 marks are uniquely enriched at static sex-biased DHS, which may serve to keep these sex-dependent hepatocyte enhancers free of H3K27me3 repressive marks and thus constitutively open. Pulsatile chromatin opening stimulated by endogenous, physiological hormone pulses is thus one of two distinct GH-determined mechanisms for establishing widespread sex differences in hepatic chromatin accessibility and epigenetic regulation, both closely linked to sex-biased gene transcription and the sexual dimorphism of liver function.
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Affiliation(s)
- Andy Rampersaud
- Department of Biology and Bioinformatics Program, Boston UniversityBostonUnited States
| | - Jeannette Connerney
- Department of Biology and Bioinformatics Program, Boston UniversityBostonUnited States
| | - David J Waxman
- Department of Biology and Bioinformatics Program, Boston UniversityBostonUnited States
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4
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Willemin G, Mange F, Praz V, Lorrain S, Cousin P, Roger C, Willis IM, Hernandez N. Contrasting effects of whole-body and hepatocyte-specific deletion of the RNA polymerase III repressor Maf1 in the mouse. Front Mol Biosci 2023; 10:1297800. [PMID: 38143800 PMCID: PMC10746880 DOI: 10.3389/fmolb.2023.1297800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 11/15/2023] [Indexed: 12/26/2023] Open
Abstract
MAF1 is a nutrient-sensitive, TORC1-regulated repressor of RNA polymerase III (Pol III). MAF1 downregulation leads to increased lipogenesis in Drosophila melanogaster, Caenorhabditis elegans, and mice. However, Maf1 -/- mice are lean as increased lipogenesis is counterbalanced by futile pre-tRNA synthesis and degradation, resulting in increased energy expenditure. We compared Chow-fed Maf1 -/- mice with Chow- or High Fat (HF)-fed Maf1 hep-/- mice that lack MAF1 specifically in hepatocytes. Unlike Maf1 -/- mice, Maf1 hep-/- mice become heavier and fattier than control mice with old age and much earlier under a HF diet. Liver ChIPseq, RNAseq and proteomics analyses indicate increased Pol III occupancy at Pol III genes, very few differences in mRNA accumulation, and protein accumulation changes consistent with increased lipogenesis. Futile pre-tRNA synthesis and degradation in the liver, as likely occurs in Maf1 hep-/- mice, thus seems insufficient to counteract increased lipogenesis. Indeed, RNAseq and metabolite profiling indicate that liver phenotypes of Maf1 -/- mice are strongly influenced by systemic inter-organ communication. Among common changes in the three phenotypically distinct cohorts, Angiogenin downregulation is likely linked to increased Pol III occupancy of tRNA genes in the Angiogenin promoter.
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Affiliation(s)
- Gilles Willemin
- Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - François Mange
- Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Viviane Praz
- Lausanne Genomic Technologies Facility, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Séverine Lorrain
- Protein Analysis Facility, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Pascal Cousin
- Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Catherine Roger
- Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Ian M. Willis
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, NY, United States
- Department of Systems and Computational Biology, Albert Einstein College of Medicine, Bronx, NY, United States
| | - Nouria Hernandez
- Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
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5
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Ansarin A, Mahdavi AM, Javadivala Z, Shanehbandi D, Zarredar H, Ansarin K. The cross-talk between leptin and circadian rhythm signaling proteins in physiological processes: a systematic review. Mol Biol Rep 2023; 50:10427-10443. [PMID: 37874505 DOI: 10.1007/s11033-023-08887-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Accepted: 10/04/2023] [Indexed: 10/25/2023]
Abstract
BACKGROUND Today, modern lifestyles and disrupted sleep patterns cause circadian clock rhythm impairments that are associated with altered leptin levels, which subsequently affect a wide range of physiological processes and have significant health burdens on societies. Nevertheless, there has been no systematic review of circadian clock genes and proteins, leptin, and related signaling pathways. METHODS Accordingly, we systematically reviewed circadian clock proteins, leptin, and molecular mechanisms between them by searching Pubmed, Scopus, ProQuest, Web of Sciences, and Google Scholar until September 2022. After considering the inclusion and exclusion criteria, 20 animal studies were selected. The risk of bias was assessed in each study. RESULTS The results clarified the reciprocal interconnected relationship between circadian clock genes and leptin. Circadian clock genes regulate leptin expression and signaling via different mechanisms, such as CLOCK-BMAL1 heterodimers, which increase the expression of PPARs. PPARs induce the expression of C/EBPα, a key factor in upregulating leptin expression. CLOCK-BMAL1 also induces the expression of Per1 and Rev-erb genes. PER1 activates mTORC1 and mTORC1 enhances the expression of C/EBPα. In addition, REV-ERBs activate the leptin signaling pathway. Also, leptin controls the expression of circadian clock genes by triggering the AMPK and ERK/MAPK signaling pathways, which regulate the activity of PPARs. Moreover, the roles of these molecular mechanisms are elucidated in different physiological processes and organs. CONCLUSIONS Crosstalk between circadian clock genes and leptin and their affecting elements should be considered in the selection of new therapeutic targets for related disorders, especially obesity and metabolic impairments.
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Affiliation(s)
- Atefeh Ansarin
- Tuberculosis and Lung Disease Research Center, Tabriz University of Medical Sciences, Pashmineh Research Complex, Daneshgah Street, P.O. Box: 5448151429, Tabriz, Iran
| | - Aida Malek Mahdavi
- Tuberculosis and Lung Disease Research Center, Tabriz University of Medical Sciences, Pashmineh Research Complex, Daneshgah Street, P.O. Box: 5448151429, Tabriz, Iran
- Connective Tissue Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Zeinab Javadivala
- Department of Health Education & Promotion, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Dariush Shanehbandi
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Habib Zarredar
- Tuberculosis and Lung Disease Research Center, Tabriz University of Medical Sciences, Pashmineh Research Complex, Daneshgah Street, P.O. Box: 5448151429, Tabriz, Iran
| | - Khalil Ansarin
- Tuberculosis and Lung Disease Research Center, Tabriz University of Medical Sciences, Pashmineh Research Complex, Daneshgah Street, P.O. Box: 5448151429, Tabriz, Iran.
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6
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Rampersaud A, Connerney J, Waxman DJ. Plasma Growth Hormone Pulses Induce Male-biased Pulsatile Chromatin Opening and Epigenetic Regulation in Adult Mouse Liver. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.21.554153. [PMID: 37662275 PMCID: PMC10473588 DOI: 10.1101/2023.08.21.554153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/05/2023]
Abstract
Sex-differences in plasma growth hormone (GH) profiles, pulsatile in males and persistent in females, regulate sex differences in hepatic STAT5 activation linked to sex differences in gene expression and liver disease susceptibility, but little is understood about the fundamental underlying, GH pattern-dependent regulatory mechanisms. Here, DNase hypersensitivity site (DHS) analysis of liver chromatin accessibility in a cohort of 18 individual male mice established that the endogenous male rhythm of plasma GH pulse-stimulated liver STAT5 activation induces dynamic, repeated cycles of chromatin opening and closing at several thousand liver DHS and comprises a novel mechanism conferring male bias to liver chromatin accessibility. Strikingly, a single physiological replacement dose of GH given to hypophysectomized male mice restored, within 30 min, liver STAT5 activity and chromatin accessibility at 83% of the pituitary hormone-dependent dynamic male-biased DHS. Sex-dependent transcription factor binding patterns and chromatin state analysis identified key genomic and epigenetic features distinguishing this dynamic, STAT5-driven mechanism of male-biased chromatin opening from a second GH-dependent mechanism operative at static male-biased DHS, which are constitutively open in male liver. Dynamic but not static male-biased DHS adopt a bivalent-like epigenetic state in female liver, as do static female-biased DHS in male liver, albeit using distinct repressive histone marks in each sex, namely, H3K27me3 at female-biased DHS in male liver, and H3K9me3 at male-biased DHS in female liver. Moreover, sex-biased H3K36me3 marks are uniquely enriched at static sex-biased DHS, which may serve to keep these sex-dependent hepatocyte enhancers free of H3K27me3 repressive marks and thus constitutively open. Pulsatile chromatin opening stimulated by endogenous, physiological hormone pulses is thus one of two distinct GH-determined mechanisms for establishing widespread sex differences in hepatic chromatin accessibility and epigenetic regulation, both closely linked to sex-biased gene transcription and the sexual dimorphism of liver function.
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Affiliation(s)
- Andy Rampersaud
- Department of Biology and Bioinformatics Program, Boston University, Boston, MA 02215 USA
| | - Jeannette Connerney
- Department of Biology and Bioinformatics Program, Boston University, Boston, MA 02215 USA
| | - David J Waxman
- Department of Biology and Bioinformatics Program, Boston University, Boston, MA 02215 USA
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7
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Sarver DC, Garcia-Diaz J, Saqib M, Riddle RC, Wong GW. Tmem263 deletion disrupts the GH/IGF-1 axis and causes dwarfism and impairs skeletal acquisition. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.02.551694. [PMID: 37577461 PMCID: PMC10418210 DOI: 10.1101/2023.08.02.551694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
Genome-wide association studies (GWAS) have identified a large number of candidate genes believed to affect longitudinal bone growth and bone mass. One of these candidate genes, TMEM263, encodes a poorly characterized plasma membrane protein. Single nucleotide polymorphisms in TMEM263 are associated with bone mineral density in humans and mutations are associated with dwarfism in chicken and severe skeletal dysplasia in at least one human fetus. Whether this genotype-phenotype relationship is causal, however, remains unclear. Here, we determine whether and how TMEM263 is required for postnatal growth. Deletion of the Tmem263 gene in mice causes severe postnatal growth failure, proportional dwarfism, and impaired skeletal acquisition. Mice lacking Tmem263 show no differences in body weight within the first two weeks of postnatal life. However, by P21 there is a dramatic growth deficit due to a disrupted GH/IGF-1 axis, which is critical for longitudinal bone growth. Tmem263-null mice have low circulating IGF-1 levels and pronounced reductions in bone mass and growth plate length. The low serum IGF-1 in Tmem263-null mice is associated with reduced hepatic GH receptor (GHR) expression and GH-induced JAK2/STAT5 signaling. A deficit in GH signaling dramatically alters GH-regulated genes and feminizes the liver transcriptome of Tmem263-null male mice, with their expression profile resembling a wild-type female, hypophysectomized male, and Stat5b-null male mice. Collectively, our data validates the causal role for Tmem263 in regulating postnatal growth and raises the possibility that rare mutations or variants of TMEM263 may potentially cause GH insensitivity and impair linear growth.
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Affiliation(s)
- Dylan C Sarver
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Jean Garcia-Diaz
- Department of Orthopaedic Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Cell and Molecular Medicine graduate program, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Muzna Saqib
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Ryan C Riddle
- Department of Orthopaedic Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Research and Development Service, Baltimore Veterans Administration Medical Center, Baltimore, Maryland, USA
| | - G William Wong
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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8
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Xiong L, Liu J, Han SY, Koppitch K, Guo JJ, Rommelfanger M, Miao Z, Gao F, Hallgrimsdottir IB, Pachter L, Kim J, MacLean AL, McMahon AP. Direct androgen receptor control of sexually dimorphic gene expression in the mammalian kidney. Dev Cell 2023; 58:2338-2358.e5. [PMID: 37673062 PMCID: PMC10873092 DOI: 10.1016/j.devcel.2023.08.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 07/20/2023] [Accepted: 08/04/2023] [Indexed: 09/08/2023]
Abstract
Mammalian organs exhibit distinct physiology, disease susceptibility, and injury responses between the sexes. In the mouse kidney, sexually dimorphic gene activity maps predominantly to proximal tubule (PT) segments. Bulk RNA sequencing (RNA-seq) data demonstrated that sex differences were established from 4 and 8 weeks after birth under gonadal control. Hormone injection studies and genetic removal of androgen and estrogen receptors demonstrated androgen receptor (AR)-mediated regulation of gene activity in PT cells as the regulatory mechanism. Interestingly, caloric restriction feminizes the male kidney. Single-nuclear multiomic analysis identified putative cis-regulatory regions and cooperating factors mediating PT responses to AR activity in the mouse kidney. In the human kidney, a limited set of genes showed conserved sex-linked regulation, whereas analysis of the mouse liver underscored organ-specific differences in the regulation of sexually dimorphic gene expression. These findings raise interesting questions on the evolution, physiological significance, disease, and metabolic linkage of sexually dimorphic gene activity.
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Affiliation(s)
- Lingyun Xiong
- Department of Stem Cell Biology and Regenerative Medicine, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90089, USA; Department of Quantitative and Computational Biology, University of Southern California, Los Angeles, CA 90089, USA
| | - Jing Liu
- Department of Stem Cell Biology and Regenerative Medicine, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90089, USA
| | - Seung Yub Han
- Graduate Program in Genomics and Computational Biology, Biomedical Graduate Studies, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Kari Koppitch
- Department of Stem Cell Biology and Regenerative Medicine, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90089, USA
| | - Jin-Jin Guo
- Department of Stem Cell Biology and Regenerative Medicine, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90089, USA
| | - Megan Rommelfanger
- Department of Quantitative and Computational Biology, University of Southern California, Los Angeles, CA 90089, USA
| | - Zhen Miao
- Graduate Program in Genomics and Computational Biology, Biomedical Graduate Studies, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Fan Gao
- Caltech Bioinformatics Resource Center at Beckman Institute, California Institute of Technology, Pasadena, CA 91125, USA
| | - Ingileif B Hallgrimsdottir
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Lior Pachter
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA; Department of Computing and Mathematical Sciences, California Institute of Technology, Pasadena, CA 91125, USA
| | - Junhyong Kim
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Adam L MacLean
- Department of Quantitative and Computational Biology, University of Southern California, Los Angeles, CA 90089, USA
| | - Andrew P McMahon
- Department of Stem Cell Biology and Regenerative Medicine, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90089, USA.
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9
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Duran-Ortiz S, Young JA, List EO, Basu R, Krejsa J, Kearns JK, Berryman DE, Kopchick JJ. GHR disruption in mature adult mice alters xenobiotic metabolism gene expression in the liver. Pituitary 2023; 26:437-450. [PMID: 37353704 DOI: 10.1007/s11102-023-01331-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/01/2023] [Indexed: 06/25/2023]
Abstract
BACKGROUND Lifelong reduction of growth hormone (GH) action extends lifespan and improves healthspan in mice. Moreover, congenital inactivating mutations of GH receptor (GHR) in mice and humans impart resistance to age-associated cancer, diabetes, and cognitive decline. To investigate the consequences of GHR disruption at an adult age, we recently ablated the GHR at 6-months of age in mature adult (6mGHRKO) mice. We found that both, male and female 6mGHRKO mice have reduced oxidative damage, with males 6mGHRKO showing improved insulin sensitivity and cancer resistance. Importantly, 6mGHRKO females have an extended lifespan compared to controls. OBJECTIVE AND METHODS To investigate the possible mechanisms leading to health improvements, we performed RNA sequencing using livers from male and female 6mGHRKO mice and controls. RESULTS We found that disrupting GH action at an adult age reduced the gap in liver gene expression between males and females, making gene expression between sexes more similar. However, there was still a 6-fold increase in the number of differentially expressed genes when comparing male 6mGHRKO mice vs controls than in 6mGHRKO female vs controls, suggesting that GHR ablation affects liver gene expression more in males than in females. Finally, we found that lipid metabolism and xenobiotic metabolism pathways are activated in the liver of 6mGHRKO mice. CONCLUSION The present study shows for the first time the specific hepatic gene expression profile, cellular pathways, biological processes and molecular mechanisms that are driven by ablating GH action at a mature adult age in males and females. Importantly, these results and future studies on xenobiotic metabolism may help explain the lifespan extension seen in 6mGHRKO mice.
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Affiliation(s)
- Silvana Duran-Ortiz
- Edison Biotechnology Institute, Ohio University, Athens, OH, 45701, USA
- Molecular and Cellular Biology Program, Ohio University, Athens, OH, USA
- Department of Biological Sciences, College of Arts and Sciences, Ohio University, Athens, OH, USA
| | - Jonathan A Young
- Edison Biotechnology Institute, Ohio University, Athens, OH, 45701, USA
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - Edward O List
- Edison Biotechnology Institute, Ohio University, Athens, OH, 45701, USA
| | - Reetobrata Basu
- Edison Biotechnology Institute, Ohio University, Athens, OH, 45701, USA
| | - Jackson Krejsa
- Edison Biotechnology Institute, Ohio University, Athens, OH, 45701, USA
| | - John K Kearns
- Edison Biotechnology Institute, Ohio University, Athens, OH, 45701, USA
| | - Darlene E Berryman
- Edison Biotechnology Institute, Ohio University, Athens, OH, 45701, USA
- Molecular and Cellular Biology Program, Ohio University, Athens, OH, USA
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA
| | - John J Kopchick
- Edison Biotechnology Institute, Ohio University, Athens, OH, 45701, USA.
- Molecular and Cellular Biology Program, Ohio University, Athens, OH, USA.
- Department of Biomedical Sciences, Heritage College of Osteopathic Medicine, Ohio University, Athens, OH, USA.
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10
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den Hartigh LJ, May KS, Zhang XS, Chait A, Blaser MJ. Serum amyloid A and metabolic disease: evidence for a critical role in chronic inflammatory conditions. Front Cardiovasc Med 2023; 10:1197432. [PMID: 37396595 PMCID: PMC10311072 DOI: 10.3389/fcvm.2023.1197432] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 05/15/2023] [Indexed: 07/04/2023] Open
Abstract
Serum amyloid A (SAA) subtypes 1-3 are well-described acute phase reactants that are elevated in acute inflammatory conditions such as infection, tissue injury, and trauma, while SAA4 is constitutively expressed. SAA subtypes also have been implicated as playing roles in chronic metabolic diseases including obesity, diabetes, and cardiovascular disease, and possibly in autoimmune diseases such as systemic lupus erythematosis, rheumatoid arthritis, and inflammatory bowel disease. Distinctions between the expression kinetics of SAA in acute inflammatory responses and chronic disease states suggest the potential for differentiating SAA functions. Although circulating SAA levels can rise up to 1,000-fold during an acute inflammatory event, elevations are more modest (∼5-fold) in chronic metabolic conditions. The majority of acute-phase SAA derives from the liver, while in chronic inflammatory conditions SAA also derives from adipose tissue, the intestine, and elsewhere. In this review, roles for SAA subtypes in chronic metabolic disease states are contrasted to current knowledge about acute phase SAA. Investigations show distinct differences between SAA expression and function in human and animal models of metabolic disease, as well as sexual dimorphism of SAA subtype responses.
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Affiliation(s)
- Laura J. den Hartigh
- Department of Medicine, Division of Metabolism, Endocrinology, and Nutrition, University of Washington, Seattle, WA, United States
- Diabetes Institute, University of Washington, Seattle, WA, United States
| | - Karolline S. May
- Department of Medicine, Division of Metabolism, Endocrinology, and Nutrition, University of Washington, Seattle, WA, United States
- Diabetes Institute, University of Washington, Seattle, WA, United States
| | - Xue-Song Zhang
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway, NJ, United States
| | - Alan Chait
- Department of Medicine, Division of Metabolism, Endocrinology, and Nutrition, University of Washington, Seattle, WA, United States
- Diabetes Institute, University of Washington, Seattle, WA, United States
| | - Martin J. Blaser
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway, NJ, United States
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11
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Xiong L, Liu J, Han SY, Koppitch K, Guo JJ, Rommelfanger M, Gao F, Hallgrimsdottir IB, Pachter L, Kim J, MacLean AL, McMahon AP. Direct androgen receptor regulation of sexually dimorphic gene expression in the mammalian kidney. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.06.539585. [PMID: 37205355 PMCID: PMC10187285 DOI: 10.1101/2023.05.06.539585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Mammalian organs exhibit distinct physiology, disease susceptibility and injury responses between the sexes. In the mouse kidney, sexually dimorphic gene activity maps predominantly to proximal tubule (PT) segments. Bulk RNA-seq data demonstrated sex differences were established from 4 and 8 weeks after birth under gonadal control. Hormone injection studies and genetic removal of androgen and estrogen receptors demonstrated androgen receptor (AR) mediated regulation of gene activity in PT cells as the regulatory mechanism. Interestingly, caloric restriction feminizes the male kidney. Single-nuclear multiomic analysis identified putative cis-regulatory regions and cooperating factors mediating PT responses to AR activity in the mouse kidney. In the human kidney, a limited set of genes showed conserved sex-linked regulation while analysis of the mouse liver underscored organ-specific differences in the regulation of sexually dimorphic gene expression. These findings raise interesting questions on the evolution, physiological significance, and disease and metabolic linkage, of sexually dimorphic gene activity.
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Affiliation(s)
- Lingyun Xiong
- Department of Stem Cell Biology and Regenerative Medicine, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90089, USA
- Department of Quantitative and Computational Biology, University of Southern California, Los Angeles, CA 90089, USA
| | - Jing Liu
- Department of Stem Cell Biology and Regenerative Medicine, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90089, USA
| | - Seung Yub Han
- Graduate Program in Genomics and Computational Biology, Biomedical Graduate Studies, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Kari Koppitch
- Department of Stem Cell Biology and Regenerative Medicine, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90089, USA
| | - Jin-Jin Guo
- Department of Stem Cell Biology and Regenerative Medicine, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90089, USA
| | - Megan Rommelfanger
- Department of Quantitative and Computational Biology, University of Southern California, Los Angeles, CA 90089, USA
| | - Fan Gao
- Caltech Bioinformatics Resource Center at Beckman Institute, California Institute of Technology, Pasadena, CA 91125, USA
| | | | - Lior Pachter
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
- Department of Computing and Mathematical Sciences, California Institute of Technology, Pasadena, CA 91125, USA
| | - Junhyong Kim
- Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Adam L. MacLean
- Department of Quantitative and Computational Biology, University of Southern California, Los Angeles, CA 90089, USA
| | - Andrew P. McMahon
- Department of Stem Cell Biology and Regenerative Medicine, Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, Keck School of Medicine of the University of Southern California, Los Angeles, CA 90089, USA
- Lead Contact
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12
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Batdorj E, AlOgayil N, Zhuang QKW, Galvez JH, Bauermeister K, Nagata K, Kimura T, Ward MA, Taketo T, Bourque G, Naumova AK. Genetic variation in the Y chromosome and sex-biased DNA methylation in somatic cells in the mouse. Mamm Genome 2023; 34:44-55. [PMID: 36454369 PMCID: PMC9947081 DOI: 10.1007/s00335-022-09970-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Accepted: 11/22/2022] [Indexed: 12/05/2022]
Abstract
Several lines of evidence suggest that the presence of the Y chromosome influences DNA methylation of autosomal loci. To better understand the impact of the Y chromosome on autosomal DNA methylation patterns and its contribution to sex bias in methylation, we identified Y chromosome dependent differentially methylated regions (yDMRs) using whole-genome bisulfite sequencing methylation data from livers of mice with different combinations of sex-chromosome complement and gonadal sex. Nearly 90% of the autosomal yDMRs mapped to transposable elements (TEs) and most of them had lower methylation in XY compared to XX or XO mice. Follow-up analyses of four reporter autosomal yDMRs showed that Y-dependent methylation levels were consistent across most somatic tissues but varied in strains with different origins of the Y chromosome, suggesting that genetic variation in the Y chromosome influenced methylation levels of autosomal regions. Mice lacking the q-arm of the Y chromosome (B6.NPYq-2) as well as mice with a loss-of-function mutation in Kdm5d showed no differences in methylation levels compared to wild type mice. In conclusion, the Y-linked modifier of TE methylation is likely to reside on the short arm of Y chromosome and further studies are required to identify this gene.
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Affiliation(s)
- Enkhjin Batdorj
- Department of Human Genetics, McGill University, Montréal, QC, H3A 1C7, Canada
| | - Najla AlOgayil
- Department of Human Genetics, McGill University, Montréal, QC, H3A 1C7, Canada
| | - Qinwei Kim-Wee Zhuang
- Department of Human Genetics, McGill University, Montréal, QC, H3A 1C7, Canada
- Canadian Centre for Computational Genomics, Montréal, QC, H3A 0G1, Canada
| | - Jose Hector Galvez
- Canadian Centre for Computational Genomics, Montréal, QC, H3A 0G1, Canada
| | - Klara Bauermeister
- Department of Human Genetics, McGill University, Montréal, QC, H3A 1C7, Canada
| | - Kei Nagata
- Laboratory of Stem Cell Biology, Department of Biosciences, Kitasato University School of Science, 1-15-1 Kitasato, Minami-Ku, Sagamihara, Kanagawa, 252-0373, Japan
| | - Tohru Kimura
- Laboratory of Stem Cell Biology, Department of Biosciences, Kitasato University School of Science, 1-15-1 Kitasato, Minami-Ku, Sagamihara, Kanagawa, 252-0373, Japan
| | - Monika A Ward
- Institute for Biogenesis Research, John A. Burns School of Medicine, University of Hawaii, 1960 East-West Road, HonoluluHonolulu, HIHI, 96822, USA
| | - Teruko Taketo
- The Research Institute of the McGill University Health Centre, Montréal, QC, H4A 3J1, Canada
- Department of Surgery, McGill University, Montréal, QC, H4A 3J1, Canada
- Department of Obstetrics and Gynecology, McGill University, Montréal, QC, H4A 3J1, Canada
| | - Guillaume Bourque
- Department of Human Genetics, McGill University, Montréal, QC, H3A 1C7, Canada
- Canadian Centre for Computational Genomics, Montréal, QC, H3A 0G1, Canada
| | - Anna K Naumova
- Department of Human Genetics, McGill University, Montréal, QC, H3A 1C7, Canada.
- The Research Institute of the McGill University Health Centre, Montréal, QC, H4A 3J1, Canada.
- Department of Obstetrics and Gynecology, McGill University, Montréal, QC, H4A 3J1, Canada.
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13
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Wiese CB, Agle ZW, Zhang P, Reue K. Chromosomal and gonadal sex drive sex differences in lipids and hepatic gene expression in response to hypercholesterolemia and statin treatment. Biol Sex Differ 2022; 13:63. [PMID: 36333813 PMCID: PMC9636767 DOI: 10.1186/s13293-022-00474-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 10/20/2022] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Biological sex impacts susceptibility and presentation of cardiovascular disease, which remains the leading cause of death for both sexes. To reduce cardiovascular disease risk, statin drugs are commonly prescribed to reduce circulating cholesterol levels through inhibition of cholesterol synthesis. The effectiveness of statin therapy differs between individuals with a sex bias in the frequency of adverse effects. Limited information is available regarding the mechanisms driving sex-specific responses to hypercholesterolemia or statin treatment. METHODS Four Core Genotypes mice (XX and XY mice with ovaries and XX and XY mice with testes) on a hypercholesteremic Apoe-/- background were fed a chow diet without or with simvastatin for 8 weeks. Plasma lipid levels were quantified and hepatic differential gene expression was evaluated with RNA-sequencing to identify the independent effects of gonadal and chromosomal sex. RESULTS In a hypercholesterolemic state, gonadal sex influenced the expression levels of more than 3000 genes, and chromosomal sex impacted expression of nearly 1400 genes, which were distributed across all autosomes as well as the sex chromosomes. Gonadal sex uniquely influenced the expression of ER stress response genes, whereas chromosomal and gonadal sex influenced fatty acid metabolism gene expression in hypercholesterolemic mice. Sex-specific effects on gene regulation in response to statin treatment included a compensatory upregulation of cholesterol biosynthetic gene expression in mice with XY chromosome complement, regardless of presence of ovaries or testes. CONCLUSION Gonadal and chromosomal sex have independent effects on the hepatic transcriptome to influence different cellular pathways in a hypercholesterolemic environment. Furthermore, chromosomal sex in particular impacted the cellular response to statin treatment. An improved understanding of how gonadal and chromosomal sex influence cellular response to disease conditions and in response to drug treatment is critical to optimize disease management for all individuals.
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Affiliation(s)
- Carrie B Wiese
- Department of Human Genetics, David Geffen School of Medicine at UCLA, Los Angeles, USA
| | - Zoey W Agle
- Department of Human Genetics, David Geffen School of Medicine at UCLA, Los Angeles, USA
| | - Peixiang Zhang
- Department of Human Genetics, David Geffen School of Medicine at UCLA, Los Angeles, USA
| | - Karen Reue
- Department of Human Genetics, David Geffen School of Medicine at UCLA, Los Angeles, USA.
- Molecular Biology Institute, University of California, Los Angeles, CA, 90024, USA.
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14
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Nikkanen J, Leong YA, Krause WC, Dermadi D, Maschek JA, Van Ry T, Cox JE, Weiss EJ, Gokcumen O, Chawla A, Ingraham HA. An evolutionary trade-off between host immunity and metabolism drives fatty liver in male mice. Science 2022; 378:290-295. [PMID: 36264814 PMCID: PMC9870047 DOI: 10.1126/science.abn9886] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Adaptations to infectious and dietary pressures shape mammalian physiology and disease risk. How such adaptations affect sex-biased diseases remains insufficiently studied. In this study, we show that sex-dependent hepatic gene programs confer a robust (~300%) survival advantage for male mice during lethal bacterial infection. The transcription factor B cell lymphoma 6 (BCL6), which masculinizes hepatic gene expression at puberty, is essential for this advantage. However, protection by BCL6 protein comes at a cost during conditions of dietary excess, which result in overt fatty liver and glucose intolerance in males. Deleting hepatic BCL6 reverses these phenotypes but markedly lowers male survival during infection, thus establishing a sex-dependent trade-off between host defense and metabolic systems. Our findings offer strong evidence that some current sex-biased diseases are rooted in ancient evolutionary trade-offs between immunity and metabolism.
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Affiliation(s)
- Joni Nikkanen
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, CA 94143, USA.,Cardiovascular Research Institute, University of California San Francisco, San Francisco, CA 94143, USA
| | - Yew Ann Leong
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, CA 94143, USA.,Centre for Inflammatory Diseases, Department of Medicine, School of Clinical Sciences at Monash Health, Monash University, Melbourne, 3800, Australia
| | - William C. Krause
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, CA 94143, USA
| | - Denis Dermadi
- Institute of Immunity, Transplantation, and Infection, Stanford University School of Medicine, Stanford, CA 94305, USA.,Biomedical Informatics Research, Department of Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - J. Alan Maschek
- Department of Biochemistry, University of Utah, Salt Lake City, UT 84112, USA.,Metabolomics Core Research Facility, University of Utah, Salt Lake City, UT 84112, USA
| | - Tyler Van Ry
- Department of Biochemistry, University of Utah, Salt Lake City, UT 84112, USA.,Metabolomics Core Research Facility, University of Utah, Salt Lake City, UT 84112, USA
| | - James E. Cox
- Department of Biochemistry, University of Utah, Salt Lake City, UT 84112, USA.,Metabolomics Core Research Facility, University of Utah, Salt Lake City, UT 84112, USA
| | - Ethan J. Weiss
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, CA 94143, USA
| | - Omer Gokcumen
- Department of Biological Sciences, University at Buffalo, Buffalo, NY 14260, USA
| | - Ajay Chawla
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, CA 94143, USA.,Departments of Physiology and Medicine, University of California San Francisco, San Francisco, CA 94143, USA.,Corresponding author. (A.C.); (H.A.I.)
| | - Holly A. Ingraham
- Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, CA 94143, USA.,Corresponding author. (A.C.); (H.A.I.)
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15
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Goldfarb CN, Karri K, Pyatkov M, Waxman DJ. Interplay Between GH-regulated, Sex-biased Liver Transcriptome and Hepatic Zonation Revealed by Single-Nucleus RNA Sequencing. Endocrinology 2022; 163:6580481. [PMID: 35512247 PMCID: PMC9154260 DOI: 10.1210/endocr/bqac059] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Indexed: 11/19/2022]
Abstract
The zonation of liver metabolic processes is well-characterized; however, little is known about the cell type-specificity and zonation of sexually dimorphic gene expression or its growth hormone (GH)-dependent transcriptional regulators. We address these issues using single-nucleus RNA-sequencing of 32 000 nuclei representing 9 major liver cell types. Nuclei were extracted from livers from adult male and female mice; from males infused with GH continuously, mimicking the female plasma GH pattern; and from mice exposed to TCPOBOP, a xenobiotic agonist ligand of the nuclear receptor CAR that perturbs sex-biased gene expression. Analysis of these rich transcriptomic datasets revealed the following: 1) expression of sex-biased genes and their GH-dependent transcriptional regulators is primarily restricted to hepatocytes and is not a feature of liver nonparenchymal cells; 2) many sex-biased transcripts show sex-dependent zonation within the liver lobule; 3) gene expression is substantially feminized both in periportal and pericentral hepatocytes when male mice are infused with GH continuously; 4) sequencing nuclei increases the sensitivity for detecting thousands of nuclear-enriched long-noncoding RNAs (lncRNAs) and enables determination of their liver cell type-specificity, sex-bias and hepatocyte zonation profiles; 5) the periportal to pericentral hepatocyte cell ratio is significantly higher in male than female liver; and 6) TCPOBOP exposure disrupts both sex-specific gene expression and hepatocyte zonation within the liver lobule. These findings highlight the complex interconnections between hepatic sexual dimorphism and zonation at the single-cell level and reveal how endogenous hormones and foreign chemical exposure can alter these interactions across the liver lobule with large effects both on protein-coding genes and lncRNAs.
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Affiliation(s)
- Christine N Goldfarb
- Department of Biology, Boston University, Boston, Massachusetts 02215, USA
- Biomedical Engineering, Boston University, Boston, Massachusetts 02215, USA
| | - Kritika Karri
- Department of Biology, Boston University, Boston, Massachusetts 02215, USA
- Bioinformatics Program Boston University, Boston, Massachusetts 02215, USA
| | - Maxim Pyatkov
- Department of Biology, Boston University, Boston, Massachusetts 02215, USA
| | - David J Waxman
- Correspondence: David J. Waxman, PhD, Department of Biology, Boston University, 5 Cummington Mall, Boston, MA 02215, USA.
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16
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Hale MD, Robinson CD, Cox CL, Cox RM. Ontogenetic Change in Male Expression of Testosterone-Responsive Genes Contributes to the Emergence of Sex-Biased Gene Expression in Anolis sagrei. Front Physiol 2022; 13:886973. [PMID: 35721538 PMCID: PMC9203151 DOI: 10.3389/fphys.2022.886973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 05/03/2022] [Indexed: 11/13/2022] Open
Abstract
Sex differences in gene expression tend to increase with age across a variety of species, often coincident with the development of sexual dimorphism and maturational changes in hormone levels. However, because most transcriptome-wide characterizations of sexual divergence are framed as comparisons of sex-biased gene expression across ages, it can be difficult to determine the extent to which age-biased gene expression within each sex contributes to the emergence of sex-biased gene expression. Using RNAseq in the liver of the sexually dimorphic brown anole lizard (Anolis sagrei), we found that a pronounced increase in sex-biased gene expression with age was associated with a much greater degree of age-biased gene expression in males than in females. This pattern suggests that developmental changes in males, such as maturational increases in circulating testosterone, contribute disproportionately to the ontogenetic emergence of sex-biased gene expression. To test this hypothesis, we used four different experimental contrasts to independently characterize sets of genes whose expression differed as a function of castration and/or treatment with exogenous testosterone. We found that genes that were significantly male-biased in expression or upregulated as males matured tended to be upregulated by testosterone, whereas genes that were female-biased or downregulated as males matured tended to be downregulated by testosterone. Moreover, the first two principal components describing multivariate gene expression indicated that exogenous testosterone reversed many of the feminizing effects of castration on the liver transcriptome of maturing males. Collectively, our results suggest that developmental changes that occur in males contribute disproportionately to the emergence of sex-biased gene expression in the Anolis liver, and that many of these changes are orchestrated by androgens such as testosterone.
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Affiliation(s)
- Matthew D. Hale
- Department of Biology, University of Virginia, Charlottesville, VA, United States
| | | | - Christian L. Cox
- College of Arts, Sciences, and Education, Florida International University, Miami, FL, United States
| | - Robert M. Cox
- Department of Biology, University of Virginia, Charlottesville, VA, United States
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17
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Genome-wide association study reveals the genetic basis of growth trait in yellow catfish with sexual size dimorphism. Genomics 2022; 114:110380. [PMID: 35533968 DOI: 10.1016/j.ygeno.2022.110380] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 04/20/2022] [Accepted: 05/02/2022] [Indexed: 01/14/2023]
Abstract
Sexual size dimorphism has been widely observed in a large number of animals including fish species. Genome-wide association study (GWAS) is a powerful tool to dissect the genetic basis of complex traits, whereas the sex-differences in the genomics of animal complex traits have been ignored in the GWAS analysis. Yellow catfish (Pelteobagrus fulvidraco) is an important aquaculture fish in China with significant sexual size dimorphism. In this study, GWAS was conducted to identify candidate SNPs and genes related to body length (BL) and body weight (BW) in 125 female yellow catfish from a breeding population. In total, one BL-related SNP and three BW-related SNPs were identified to be significantly associated with the traits. Besides, one of these SNPs (Chr15:19195072) was shared in both the BW and BL traits in female yellow catfish, which was further validated in 185 male individuals and located on the exon of stat5b gene. Transgenic yellow catfish and zebrafish that expressed yellow catfish stat5b showed increased growth rate and reduction of sexual size dimorphism. These results not only reveal the genetic basis of growth trait and sexual size dimorphism in fish species, but also provide useful information for the marker-assisted breeding in yellow catfish.
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18
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Lau-Corona D, Ma H, Vergato C, Sarmento-Cabral A, del Rio-Moreno M, Kineman RD, Waxman DJ. Constitutively Active STAT5b Feminizes Mouse Liver Gene Expression. Endocrinology 2022; 163:bqac046. [PMID: 35396838 PMCID: PMC9070516 DOI: 10.1210/endocr/bqac046] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Indexed: 11/19/2022]
Abstract
STAT5 is an essential transcriptional regulator of the sex-biased actions of GH in the liver. Delivery of constitutively active STAT5 (STAT5CA) to male mouse liver using an engineered adeno-associated virus with high tropism for the liver is shown to induce widespread feminization of the liver, with extensive induction of female-biased genes and repression of male-biased genes, largely mimicking results obtained when male mice are given GH as a continuous infusion. Many of the STAT5CA-responding genes were associated with nearby (< 50 kb) sites of STAT5 binding to liver chromatin, supporting the proposed direct role of persistently active STAT5 in continuous GH-induced liver feminization. The feminizing effects of STAT5CA were dose-dependent; moreover, at higher levels, STAT5CA overexpression resulted in some histopathology, including hepatocyte hyperplasia, and increased karyomegaly and multinuclear hepatocytes. These findings establish that the persistent activation of STAT5 by GH that characterizes female liver is by itself sufficient to account for the sex-dependent expression of a majority of hepatic sex-biased genes. Moreover, histological changes seen when STAT5CA is overexpressed highlight the importance of carefully evaluating such effects before considering STAT5 derivatives for therapeutic use in treating liver disease.
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Affiliation(s)
- Dana Lau-Corona
- Department of Biology and Bioinformatics Program, Boston University, Boston, MA 02215, USA
| | - Hong Ma
- Department of Biology and Bioinformatics Program, Boston University, Boston, MA 02215, USA
| | - Cameron Vergato
- Department of Biology and Bioinformatics Program, Boston University, Boston, MA 02215, USA
| | - Andre Sarmento-Cabral
- Department of Medicine, Section of Endocrinology, Diabetes, and Metabolism, University of Illinois at Chicago and Research and Development Division, Jesse Brown VA Medical Center, Chicago, IL 60612, USA
| | - Mercedes del Rio-Moreno
- Department of Medicine, Section of Endocrinology, Diabetes, and Metabolism, University of Illinois at Chicago and Research and Development Division, Jesse Brown VA Medical Center, Chicago, IL 60612, USA
| | - Rhonda D Kineman
- Department of Medicine, Section of Endocrinology, Diabetes, and Metabolism, University of Illinois at Chicago and Research and Development Division, Jesse Brown VA Medical Center, Chicago, IL 60612, USA
| | - David J Waxman
- Department of Biology and Bioinformatics Program, Boston University, Boston, MA 02215, USA
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19
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Penn DJ, Zala SM, Luzynski KC. Regulation of Sexually Dimorphic Expression of Major Urinary Proteins. Front Physiol 2022; 13:822073. [PMID: 35431992 PMCID: PMC9008510 DOI: 10.3389/fphys.2022.822073] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 02/21/2022] [Indexed: 11/15/2022] Open
Abstract
Male house mice excrete large amounts of protein in their urinary scent marks, mainly composed of Major Urinary Proteins (MUPs), and these lipocalins function as pheromones and pheromone carriers. Here, we review studies on sexually dimorphic MUP expression in house mice, including the proximate mechanisms controlling MUP gene expression and their adaptive functions. Males excrete 2 to 8 times more urinary protein than females, though there is enormous variation in gene expression across loci in both sexes. MUP expression is dynamically regulated depending upon a variety of factors. Males regulate MUP expression according to social status, whereas females do not, and males regulate expression depending upon health and condition. Male-biased MUP expression is regulated by pituitary secretion of growth hormone (GH), which binds receptors in the liver, activating the JAK2-STAT5 signaling pathway, chromatin accessibility, and MUP gene transcription. Pulsatile male GH secretion is feminized by several factors, including caloric restriction, microbiota depletion, and aging, which helps explain condition-dependent MUP expression. If MUP production has sex-specific fitness optima, then this should generate sexual antagonism over allelic expression (intra-locus sexual conflict) selectively favoring sexually dimorphic expression. MUPs influence the sexual attractiveness of male urinary odor and increased urinary protein excretion is correlated with the reproductive success of males but not females. This finding could explain the selective maintenance of sexually dimorphic MUP expression. Producing MUPs entails energetic costs, but increased excretion may reduce the net energetic costs and predation risks from male scent marking as well as prolong the release of chemical signals. MUPs may also provide physiological benefits, including regulating metabolic rate and toxin removal, which may have sex-specific effects on survival. A phylogenetic analysis on the origins of male-biased MUP gene expression in Mus musculus suggests that this sexual dimorphism evolved by increasing male MUP expression rather than reducing female expression.
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20
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Summers KM, Bush SJ, Wu C, Hume DA. Generation and network analysis of an RNA-seq transcriptional atlas for the rat. NAR Genom Bioinform 2022; 4:lqac017. [PMID: 35265836 PMCID: PMC8900154 DOI: 10.1093/nargab/lqac017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Revised: 01/13/2022] [Accepted: 02/15/2022] [Indexed: 12/19/2022] Open
Abstract
Abstract
The laboratory rat is an important model for biomedical research. To generate a comprehensive rat transcriptomic atlas, we curated and downloaded 7700 rat RNA-seq datasets from public repositories, downsampled them to a common depth and quantified expression. Data from 585 rat tissues and cells, averaged from each BioProject, can be visualized and queried at http://biogps.org/ratatlas. Gene co-expression network (GCN) analysis revealed clusters of transcripts that were tissue or cell type restricted and contained transcription factors implicated in lineage determination. Other clusters were enriched for transcripts associated with biological processes. Many of these clusters overlap with previous data from analysis of other species, while some (e.g. expressed specifically in immune cells, retina/pineal gland, pituitary and germ cells) are unique to these data. GCN analysis on large subsets of the data related specifically to liver, nervous system, kidney, musculoskeletal system and cardiovascular system enabled deconvolution of cell type-specific signatures. The approach is extensible and the dataset can be used as a point of reference from which to analyse the transcriptomes of cell types and tissues that have not yet been sampled. Sets of strictly co-expressed transcripts provide a resource for critical interpretation of single-cell RNA-seq data.
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Affiliation(s)
- Kim M Summers
- Mater Research Institute—University of Queensland, Translational Research Institute, 37 Kent St, Woolloongabba, QLD 4102, Australia
| | - Stephen J Bush
- Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, OX3 9DS, UK
| | - Chunlei Wu
- Department of Integrative and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - David A Hume
- Mater Research Institute—University of Queensland, Translational Research Institute, 37 Kent St, Woolloongabba, QLD 4102, Australia
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21
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Frias-Soler RC, Kelsey NA, Villarín Pildaín L, Wink M, Bairlein F. Transcriptome signature changes in the liver of a migratory passerine. Genomics 2022; 114:110283. [PMID: 35143886 DOI: 10.1016/j.ygeno.2022.110283] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 12/13/2021] [Accepted: 01/31/2022] [Indexed: 12/01/2022]
Abstract
The liver plays a principal role in avian migration. Here, we characterised the liver transcriptome of a long-distance migrant, the Northern Wheatear (Oenanthe oenanthe), sampled at different migratory stages, looking for molecular processes linked with adaptations to migration. The analysis of the differentially expressed genes suggested changes in the periods of the circadian rhythm, variation in the proportion of cells in G1/S cell-cycle stages and the putative polyploidization of this cell population. This may explain the dramatic increment in the liver's metabolic capacities towards migration. Additionally, genes involved in anti-oxidative stress, detoxification and innate immune responses, lipid metabolism, inflammation and angiogenesis were regulated. Lipophagy and lipid catabolism were active at all migratory stages and increased towards the fattening and fat periods, explaining the relevance of lipolysis in controlling steatosis and maintaining liver health. Our study clears the way for future functional studies regarding long-distance avian migration.
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Affiliation(s)
- Roberto Carlos Frias-Soler
- Institute of Avian Research, An der Vogelwarte 21, 26386 Wilhelmshaven, Germany; Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Im Neuenheimer Feld 364, 69120 Heidelberg, Germany.
| | - Natalie A Kelsey
- Institute of Avian Research, An der Vogelwarte 21, 26386 Wilhelmshaven, Germany.
| | - Lilian Villarín Pildaín
- Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Im Neuenheimer Feld 364, 69120 Heidelberg, Germany
| | - Michael Wink
- Institute of Pharmacy and Molecular Biotechnology, Heidelberg University, Im Neuenheimer Feld 364, 69120 Heidelberg, Germany.
| | - Franz Bairlein
- Institute of Avian Research, An der Vogelwarte 21, 26386 Wilhelmshaven, Germany; Max Planck Institute of Animal Behavior, Am Obstberg 1, 78315 Radolfzell, Germany.
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22
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Matthews BJ, Melia T, Waxman DJ. Harnessing natural variation to identify cis regulators of sex-biased gene expression in a multi-strain mouse liver model. PLoS Genet 2021; 17:e1009588. [PMID: 34752452 PMCID: PMC8664386 DOI: 10.1371/journal.pgen.1009588] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 12/10/2021] [Accepted: 10/27/2021] [Indexed: 12/13/2022] Open
Abstract
Sex differences in gene expression are widespread in the liver, where many autosomal factors act in tandem with growth hormone signaling to regulate individual variability of sex differences in liver metabolism and disease. Here, we compare hepatic transcriptomic and epigenetic profiles of mouse strains C57BL/6J and CAST/EiJ, representing two subspecies separated by 0.5-1 million years of evolution, to elucidate the actions of genetic factors regulating liver sex differences. We identify 144 protein coding genes and 78 lncRNAs showing strain-conserved sex bias; many have gene ontologies relevant to liver function, are more highly liver-specific and show greater sex bias, and are more proximally regulated than genes whose sex bias is strain-dependent. The strain-conserved genes include key growth hormone-dependent transcriptional regulators of liver sex bias; however, three other transcription factors, Trim24, Tox, and Zfp809, lose their sex-biased expression in CAST/EiJ mouse liver. To elucidate the observed strain specificities in expression, we characterized the strain-dependence of sex-biased chromatin opening and enhancer marks at cis regulatory elements (CREs) within expression quantitative trait loci (eQTL) regulating liver sex-biased genes. Strikingly, 208 of 286 eQTLs with strain-specific, sex-differential effects on expression were associated with a complete gain, loss, or reversal of the sex differences in expression between strains. Moreover, 166 of the 286 eQTLs were linked to the strain-dependent gain or loss of localized sex-biased CREs. Remarkably, a subset of these CREs apparently lacked strain-specific genetic variants yet showed coordinated, strain-dependent sex-biased epigenetic regulation. Thus, we directly link hundreds of strain-specific genetic variants to the high variability in CRE activity and expression of sex-biased genes and uncover underlying genetically-determined epigenetic states controlling liver sex bias in genetically diverse mouse populations.
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Affiliation(s)
- Bryan J. Matthews
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
| | - Tisha Melia
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
- Bioinformatics Program, Boston University, Boston, Massachusetts, United States of America
| | - David J. Waxman
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
- Bioinformatics Program, Boston University, Boston, Massachusetts, United States of America
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23
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Lefebvre P, Staels B. Hepatic sexual dimorphism - implications for non-alcoholic fatty liver disease. Nat Rev Endocrinol 2021; 17:662-670. [PMID: 34417588 DOI: 10.1038/s41574-021-00538-6] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/06/2021] [Indexed: 12/14/2022]
Abstract
The liver is often thought of as a single functional unit, but both its structural and functional architecture make it highly multivalent and adaptable. In any given physiological situation, the liver can maintain metabolic homeostasis, conduct appropriate inflammatory responses, carry out endobiotic and xenobiotic transformation and synthesis reactions, as well as store and release multiple bioactive molecules. Moreover, the liver is a very resilient organ. This resilience means that chronic liver diseases can go unnoticed for decades, yet culminate in life-threatening clinical complications once the adaptive capacity of the liver is overwhelmed. Non-alcoholic fatty liver disease (NAFLD) predisposes individuals to cirrhosis and increases liver-related and cardiovascular disease-related mortality. This Review discusses the accumulating evidence of sexual dimorphism in NAFLD, which is currently rarely considered in preclinical and clinical studies. Increased awareness of the mechanistic causes of hepatic sexual dimorphism could lead to improved understanding of the biological processes that are dysregulated in NAFLD, to the identification of relevant therapeutic targets and to improved risk stratification of patients with NAFLD undergoing therapeutic intervention.
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Affiliation(s)
- Philippe Lefebvre
- Université Lille, INSERM, CHU Lille, Institut Pasteur de Lille, Lille, France.
| | - Bart Staels
- Université Lille, INSERM, CHU Lille, Institut Pasteur de Lille, Lille, France
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24
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Boutot ME, Whitcomb BW, Abdelouahab N, Baccarelli AA, Boivin A, Caku A, Gillet V, Martinez G, Pasquier JC, Zhu J, Takser L, St-Cyr L, Suvorov A. In Utero Exposure to Persistent Organic Pollutants and Childhood Lipid Levels. Metabolites 2021; 11:657. [PMID: 34677372 PMCID: PMC8540619 DOI: 10.3390/metabo11100657] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 09/21/2021] [Accepted: 09/24/2021] [Indexed: 12/15/2022] Open
Abstract
Animal studies have shown that developmental exposures to polybrominated diphenyl ethers (PBDE) permanently affect blood/liver balance of lipids. No human study has evaluated associations between in utero exposures to persistent organic pollutants (POPs) and later life lipid metabolism. In this pilot, maternal plasma levels of PBDEs (BDE-47, BDE-99, BDE-100, and BDE-153) and polychlorinated biphenyls (PCB-138, PCB-153, and PCB-180) were determined at delivery in participants of GESTation and Environment (GESTE) cohort. Total cholesterol (TCh), triglycerides (TG), low- and high-density lipoproteins (LDL-C and HDL-C), total lipids (TL), and PBDEs were determined in serum of 147 children at ages 6-7. General linear regression was used to estimate the relationship between maternal POPs and child lipid levels with adjustment for potential confounders, and adjustment for childhood POPs. In utero BDE-99 was associated with lower childhood levels of TG (p = 0.003), and non-significantly with HDL-C (p = 0.06) and TL (p = 0.07). Maternal PCB-138 was associated with lower childhood levels of TG (p = 0.04), LDL-C (p = 0.04), and TL (p = 0.02). Our data indicate that in utero exposures to POPs may be associated with long lasting decrease in circulating lipids in children, suggesting increased lipid accumulation in the liver, a mechanism involved in NAFLD development, consistent with previously reported animal data.
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Affiliation(s)
- Maegan E. Boutot
- Department of Biostatistics and Epidemiology, School of Public Health and Health Sciences, University of Massachusetts Amherst, Amherst, MA 01003, USA; (M.E.B.); (B.W.W.)
| | - Brian W. Whitcomb
- Department of Biostatistics and Epidemiology, School of Public Health and Health Sciences, University of Massachusetts Amherst, Amherst, MA 01003, USA; (M.E.B.); (B.W.W.)
| | - Nadia Abdelouahab
- Department of Obstetrics and Gynecology, Faculty of Medicine and Health Sciences, Sherbrooke University, Sherbrooke, QC J1H 5N4, Canada; (N.A.); (J.-C.P.)
| | - Andrea A. Baccarelli
- Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY 10032, USA;
| | - Amélie Boivin
- Department of Pediatrics, Faculty of Medicine and Health Sciences, Sherbrooke University, Sherbrooke, QC J1H 5N4, Canada; (A.B.); (V.G.); (L.S.-C.)
| | - Artuela Caku
- Department of Biochemistry and Functional Genomics, Faculty of Medicine and Health Sciences, Sherbrooke University, Sherbrooke, QC J1H 5N4, Canada;
| | - Virginie Gillet
- Department of Pediatrics, Faculty of Medicine and Health Sciences, Sherbrooke University, Sherbrooke, QC J1H 5N4, Canada; (A.B.); (V.G.); (L.S.-C.)
| | - Guillaume Martinez
- Department of Chemistry, Faculty of Sciences, Sherbrooke, QC J1K 2R1, Canada;
| | - Jean-Charles Pasquier
- Department of Obstetrics and Gynecology, Faculty of Medicine and Health Sciences, Sherbrooke University, Sherbrooke, QC J1H 5N4, Canada; (N.A.); (J.-C.P.)
| | - Jiping Zhu
- Environmental Health Science and Research Bureau, Health Canada, Ottawa, ON K1A 0K9, Canada;
| | - Larissa Takser
- Department of Pediatrics & Department of Psychiatry, Faculty of Medicine and Health Sciences, Sherbrooke University, Sherbrooke, QC J1H 5N4, Canada;
| | - Lindsay St-Cyr
- Department of Pediatrics, Faculty of Medicine and Health Sciences, Sherbrooke University, Sherbrooke, QC J1H 5N4, Canada; (A.B.); (V.G.); (L.S.-C.)
| | - Alexander Suvorov
- Department of Biostatistics and Epidemiology, School of Public Health and Health Sciences, University of Massachusetts Amherst, Amherst, MA 01003, USA; (M.E.B.); (B.W.W.)
- Department of Environmental Health Sciences, School of Public Health and Health Sciences, University of Massachusetts Amherst, Amherst, MA 01003, USA
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25
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Saitou M, Resendez S, Pradhan AJ, Wu F, Lie NC, Hall NJ, Zhu Q, Reinholdt L, Satta Y, Speidel L, Nakagome S, Hanchard NA, Churchill G, Lee C, Atilla-Gokcumen GE, Mu X, Gokcumen O. Sex-specific phenotypic effects and evolutionary history of an ancient polymorphic deletion of the human growth hormone receptor. SCIENCE ADVANCES 2021; 7:eabi4476. [PMID: 34559564 PMCID: PMC8462886 DOI: 10.1126/sciadv.abi4476] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 08/04/2021] [Indexed: 06/13/2023]
Abstract
The common deletion of the third exon of the growth hormone receptor gene (GHRd3) in humans is associated with birth weight, growth after birth, and time of puberty. However, its evolutionary history and the molecular mechanisms through which it affects phenotypes remain unresolved. We present evidence that this deletion was nearly fixed in the ancestral population of anatomically modern humans and Neanderthals but underwent a recent adaptive reduction in frequency in East Asia. We documented that GHRd3 is associated with protection from severe malnutrition. Using a novel mouse model, we found that, under calorie restriction, Ghrd3 leads to the female-like gene expression in male livers and the disappearance of sexual dimorphism in weight. The sex- and diet-dependent effects of GHRd3 in our mouse model are consistent with a model in which the allele frequency of GHRd3 varies throughout human evolution as a response to fluctuations in resource availability.
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Affiliation(s)
- Marie Saitou
- Department of Biological Sciences, University at Buffalo, Buffalo, NY, USA
| | - Skyler Resendez
- Department of Biological Sciences, University at Buffalo, Buffalo, NY, USA
| | | | - Fuguo Wu
- Department of Ophthalmology, Ross Eye Institute, Jacobs School of Medicine and Biological Sciences, University at Buffalo, Buffalo, NY, USA
| | - Natasha C. Lie
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Nancy J. Hall
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Qihui Zhu
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA
| | | | - Yoko Satta
- Department of Evolutionary Studies of Biosystems, SOKENDAI (Graduate University for Advanced Studies), Kanagawa Prefecture, Japan
| | - Leo Speidel
- University College London, Genetics Institute, London, UK
- The Francis Crick Institute, London, UK
| | | | - Neil A. Hanchard
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | | | - Charles Lee
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA
- Precision Medicine Center, The First Affiliated Hospital of Xi’an Jiaotong University, Shaanxi, People’s Republic of China
| | | | - Xiuqian Mu
- Department of Ophthalmology, Ross Eye Institute, Jacobs School of Medicine and Biological Sciences, University at Buffalo, Buffalo, NY, USA
| | - Omer Gokcumen
- Department of Biological Sciences, University at Buffalo, Buffalo, NY, USA
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26
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Della Torre S. Beyond the X Factor: Relevance of Sex Hormones in NAFLD Pathophysiology. Cells 2021; 10:2502. [PMID: 34572151 PMCID: PMC8470830 DOI: 10.3390/cells10092502] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 09/12/2021] [Accepted: 09/14/2021] [Indexed: 12/12/2022] Open
Abstract
Non-alcoholic fatty liver disease (NAFLD) is a major health issue worldwide, being frequently associated with obesity, unbalanced dietary regimens, and reduced physical activity. Despite their greater adiposity and reduced physical activity, women show a lower risk of developing NAFLD in comparison to men, likely a consequence of a sex-specific regulation of liver metabolism. In the liver, sex differences in the uptake, synthesis, oxidation, deposition, and mobilization of lipids, as well as in the regulation of inflammation, are associated with differences in NAFLD prevalence and progression between men and women. Given the major role of sex hormones in driving hepatic sexual dimorphism, this review will focus on the role of sex hormones and their signaling in the regulation of hepatic metabolism and in the molecular mechanisms triggering NAFLD development and progression.
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Affiliation(s)
- Sara Della Torre
- Department of Pharmaceutical Sciences, University of Milan, Via Balzaretti 9, 20133 Milan, Italy
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27
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Sex-dependent dynamics of metabolism in primary mouse hepatocytes. Arch Toxicol 2021; 95:3001-3013. [PMID: 34241659 PMCID: PMC8380230 DOI: 10.1007/s00204-021-03118-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 07/01/2021] [Indexed: 11/12/2022]
Abstract
The liver is one of the most sexually dimorphic organs. The hepatic metabolic pathways that are subject to sexual dimorphism include xenobiotic, amino acid and lipid metabolism. Non-alcoholic fatty liver disease and hepatocellular carcinoma are among diseases with sex-dependent prevalence, progression and outcome. Although male and female livers differ in their abilities to metabolize foreign compounds, including drugs, sex-dependent treatment and pharmacological dynamics are rarely applied in all relevant cases. Therefore, it is important to consider hepatic sexual dimorphism when developing new treatment strategies and to understand the underlying mechanisms in model systems. We isolated primary hepatocytes from male and female C57BL6/N mice and examined the sex-dependent transcriptome, proteome and extracellular metabolome parameters in the course of culturing them for 96 h. The sex-specific gene expression of the general xenobiotic pathway altered and the female-specific expression of Cyp2b13 and Cyp2b9 was significantly reduced during culture. Sex-dependent differences of several signaling pathways increased, including genes related to serotonin and melatonin degradation. Furthermore, the ratios of male and female gene expression were inversed for other pathways, such as amino acid degradation, beta-oxidation, androgen signaling and hepatic steatosis. Because the primary hepatocytes were cultivated without the influence of known regulators of sexual dimorphism, these results suggest currently unknown modulatory mechanisms of sexual dimorphism in vitro. The large sex-dependent differences in the regulation and dynamics of drug metabolism observed during cultivation can have an immense influence on the evaluation of pharmacodynamic processes when conducting initial preclinical trials to investigate potential new drugs.
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28
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AlOgayil N, Bauermeister K, Galvez JH, Venkatesh VS, Zhuang QKW, Chang ML, Davey RA, Zajac JD, Ida K, Kamiya A, Taketo T, Bourque G, Naumova AK. Distinct roles of androgen receptor, estrogen receptor alpha, and BCL6 in the establishment of sex-biased DNA methylation in mouse liver. Sci Rep 2021; 11:13766. [PMID: 34215813 PMCID: PMC8253761 DOI: 10.1038/s41598-021-93216-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Accepted: 06/22/2021] [Indexed: 12/13/2022] Open
Abstract
Sexual dimorphism in gene regulation, including DNA methylation, is the main driver of sexual dimorphism in phenotypes. However, the questions of how and when sex shapes DNA methylation remain unresolved. Recently, using mice with different combinations of genetic and phenotypic sex, we identified sex-associated differentially methylated regions (sDMRs) that depended on the sex phenotype. Focusing on a panel of validated sex-phenotype dependent male- and female-biased sDMRs, we tested the developmental dynamics of sex bias in liver methylation and the impacts of mutations in the androgen receptor, estrogen receptor alpha, or the transcriptional repressor Bcl6 gene. True hermaphrodites that carry both unilateral ovaries and contralateral testes were also tested. Our data show that sex bias in methylation either coincides with or follows sex bias in the expression of sDMR-proximal genes, suggesting that sex bias in gene expression may be required for demethylation at certain sDMRs. Global ablation of AR, ESR1, or a liver-specific loss of BCL6, all alter sDMR methylation, whereas presence of both an ovary and a testis delays the establishment of male-type methylation levels in hermaphrodites. Moreover, the Bcl6-LKO shows dissociation between expression and methylation, suggesting a distinct role of BCL6 in demethylation of intragenic sDMRs.
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Affiliation(s)
- Najla AlOgayil
- Department of Human Genetics, McGill University, Montréal, QC, Canada
| | | | | | - Varun S Venkatesh
- Department of Medicine, Austin Health, The University of Melbourne, Heidelberg, VIC, 3084, Australia
| | | | - Matthew L Chang
- Department of Biochemistry, McGill University, Montréal, QC, Canada
| | - Rachel A Davey
- Department of Medicine, Austin Health, The University of Melbourne, Heidelberg, VIC, 3084, Australia
| | - Jeffrey D Zajac
- Department of Medicine, Austin Health, The University of Melbourne, Heidelberg, VIC, 3084, Australia
| | - Kinuyo Ida
- Department of Molecular Life Sciences, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, 259-1193, Japan
| | - Akihide Kamiya
- Department of Molecular Life Sciences, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, 259-1193, Japan
| | - Teruko Taketo
- The Research Institute of the McGill University Health Centre, Montreal, QC, H4A 1J3, Canada.,Department of Surgery, McGill University, Montreal, QC, Canada.,Department of Obstetrics and Gynecology, McGill University, Montreal, QC, Canada
| | - Guillaume Bourque
- Department of Human Genetics, McGill University, Montréal, QC, Canada.,Canadian Centre for Computational Genomics, Montréal, QC, Canada
| | - Anna K Naumova
- Department of Human Genetics, McGill University, Montréal, QC, Canada. .,The Research Institute of the McGill University Health Centre, Montreal, QC, H4A 1J3, Canada. .,Department of Obstetrics and Gynecology, McGill University, Montreal, QC, Canada.
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29
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Sidhom S, Schneider A, Fang Y, McFadden S, Darcy J, Sathiaseelan R, Palmer AK, Steyn FJ, Grillari J, Kopchick JJ, Bartke A, Siddiqi S, Masternak MM, Stout MB. 17α-Estradiol Modulates IGF1 and Hepatic Gene Expression in a Sex-Specific Manner. J Gerontol A Biol Sci Med Sci 2021; 76:778-785. [PMID: 32857104 PMCID: PMC8087270 DOI: 10.1093/gerona/glaa215] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Indexed: 12/13/2022] Open
Abstract
Aging is the greatest risk factor for most chronic diseases. The somatotropic axis is one of the most conserved biological pathways that regulates aging across species. 17α-Estradiol (17α-E2), a diastereomer of 17β-estradiol (17β-E2), was recently found to elicit health benefits, including improved insulin sensitivity and extend longevity exclusively in male mice. Given that 17β-E2 is known to modulate somatotropic signaling in females through actions in the pituitary and liver, we hypothesized that 17α-E2 may be modulating the somatotropic axis in males, thereby contributing to health benefits. Herein, we demonstrate that 17α-E2 increases hepatic insulin-like growth factor 1 (IGF1) production in male mice without inducing any changes in pulsatile growth hormone (GH) secretion. Using growth hormone receptor knockout (GHRKO) mice, we subsequently determined that the induction of hepatic IGF1 by 17α-E2 is dependent upon GH signaling in male mice, and that 17α-E2 elicits no effects on IGF1 production in female mice. We also determined that 17α-E2 failed to feminize the hepatic transcriptional profile in normal (N) male mice, as evidenced by a clear divergence between the sexes, regardless of treatment. Conversely, significant overlap in transcriptional profiles was observed between sexes in GHRKO mice, and this was unaffected by 17α-E2 treatment. Based on these findings, we propose that 17α-E2 acts as a pleiotropic pathway modulator in male mice by uncoupling IGF1 production from insulin sensitivity. In summary, 17α-E2 treatment upregulates IGF1 production in wild-type (and N) male mice in what appears to be a GH-dependent fashion, while no effects in female IGF1 production are observed following 17α-E2 treatment.
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Affiliation(s)
- Silvana Sidhom
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando
| | - Augusto Schneider
- Faculdade de Nutrição, Universidade Federal de Pelotas, Rio Grande do Sul, Brazil
| | - Yimin Fang
- Department of Physiology, Southern Illinois University School of Medicine, Springfield
| | - Samuel McFadden
- Department of Physiology, Southern Illinois University School of Medicine, Springfield
| | - Justin Darcy
- Department of Physiology, Southern Illinois University School of Medicine, Springfield
| | - Roshini Sathiaseelan
- Department of Nutritional Sciences, University of Oklahoma Health Sciences Center
| | - Allyson K Palmer
- Robert and Arlene Kogod Center on Aging, Mayo Clinic, Rochester, Minnesota
| | - Frederik J Steyn
- University of Queensland Centre for Clinical Research, Faculty of Medicine, Brisbane, Australia
| | - Johannes Grillari
- Department of Biotechnology, BOKU – University of Natural Resources and Life Sciences, Vienna, Austria
| | - John J Kopchick
- Edison Biotechnology Institute & Heritage College of Osteopathic Medicine, Ohio University, Athens
| | - Andrzej Bartke
- Department of Physiology, Southern Illinois University School of Medicine, Springfield
| | - Shadab Siddiqi
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando
| | - Michal M Masternak
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, Orlando
| | - Michael B Stout
- Department of Nutritional Sciences, University of Oklahoma Health Sciences Center
- Oklahoma Center for Geroscience, University of Oklahoma Health Sciences Center
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30
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Le Magueresse-Battistoni B. Endocrine disrupting chemicals and metabolic disorders in the liver: What if we also looked at the female side? CHEMOSPHERE 2021; 268:129212. [PMID: 33359838 DOI: 10.1016/j.chemosphere.2020.129212] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 12/01/2020] [Accepted: 12/02/2020] [Indexed: 05/07/2023]
Abstract
Endocrine disrupting chemicals (EDCs) are linked to the worldwide epidemic incidence of metabolic disorders and fatty liver diseases, which affects quality of life and represents a high economic cost to society. Energy homeostasis exhibits strong sexual dimorphic traits, and metabolic organs respond to EDCs depending on sex, such as the liver, which orchestrates both drug elimination and glucose and lipid metabolism. In addition, fatty liver diseases show a strong sexual bias, which in part could also originate from sex differences observed in gut microbiota. The aim of this review is to highlight significant differences in endocrine and metabolic aspects of the liver, between males and females throughout development and into adulthood. It is also to illustrate how the male and female liver differently cope with exposure to various EDCs such as bisphenols, phthalates and persistent organic chemicals in order to draw attention to the need to include both sexes in experimental studies. Interesting data come from analyses of the composition and diversity of the gut microbiota in males exposed to the mentioned EDCs showing significant correlations with hepatic lipid accumulation and metabolic disorders but information on females is lacking or incomplete. As industrialization increases, the list of anthropogenic chemicals to which humans will be exposed will also likely increase. In addition to strengthening existing regulations, encouraging populations to protect themselves and promoting the substitution of harmful chemicals with safe products, innovative strategies based on sex differences in the gut microbiota and in the gut-liver axis could be optimistic outlook.
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31
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Schoeller EL, Tonsfeldt KJ, Sinkovich M, Shi R, Mellon PL. Growth Hormone Pulses and Liver Gene Expression Are Differentially Regulated by the Circadian Clock Gene Bmal1. Endocrinology 2021; 162:6128829. [PMID: 33539533 PMCID: PMC7901660 DOI: 10.1210/endocr/bqab023] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Indexed: 12/16/2022]
Abstract
In this study, we found that loss of the circadian clock gene Bmal1 causes disruptions throughout the growth hormone (GH) axis, from hepatic gene expression to production of urinary pheromones and pheromone-dependent behavior. First, we show that Bmal1 knockout (KO) males elicit reduced aggressive responses from wild-type (WT) males and secrete lower levels of major urinary proteins (MUPs); however, we also found that a liver-specific KO of Bmal1 (liver-Bmal1-KO) produces a similar reduction in MUP secretion without a defect in aggressive behavior, indicating that the decrease in elicited aggression arises from another factor. We then shifted our investigation to determine the cause of MUP dysregulation in Bmal1 KO animals. Because the pulse pattern of GH drives sexually dimorphic expression of hepatic genes including MUPs, we examined GH pulsatility. We found that Bmal1 KO males have a female-like pattern of GH release, whereas liver-Bmal1-KO mice are not significantly different from either WT or Bmal1 KO. Since differential patterns of GH release regulate the transcription of many sexually dimorphic genes in the liver, we then examined hepatic gene transcription in Bmal1 KO and liver-Bmal1-KO mice. We found that while some female-predominant genes increase in the Bmal1 KO, there was no decrease in male-predominant genes, and little change in the liver-Bmal1-KO. We also found disrupted serum insulin growth factor 1 (IGF-1) and liver Igf1 messenger RNA in the Bmal1 KO mice, which may underlie the disrupted GH release. Overall, our findings differentiate between GH-pulse-driven and circadian-driven effects on hepatic genes, and the functional consequences of altered GH pulsatility.
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Affiliation(s)
- Erica L Schoeller
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Center for Reproductive Science and Medicine, University of California, San Diego, La Jolla, California, USA
| | - Karen J Tonsfeldt
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Center for Reproductive Science and Medicine, University of California, San Diego, La Jolla, California, USA
| | - McKenna Sinkovich
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Center for Reproductive Science and Medicine, University of California, San Diego, La Jolla, California, USA
| | - Rujing Shi
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Center for Reproductive Science and Medicine, University of California, San Diego, La Jolla, California, USA
| | - Pamela L Mellon
- Department of Obstetrics, Gynecology, and Reproductive Sciences, Center for Reproductive Science and Medicine, University of California, San Diego, La Jolla, California, USA
- Correspondence: Pamela L. Mellon, PhD, Department of Obstetrics, Gynecology, and Reproductive Sciences, Center for Reproductive Science and Medicine, University of California, San Diego, 9500 Gilman Dr, La Jolla, CA 92093-0674, USA. )
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Goldfarb CN, Waxman DJ. Global analysis of expression, maturation and subcellular localization of mouse liver transcriptome identifies novel sex-biased and TCPOBOP-responsive long non-coding RNAs. BMC Genomics 2021; 22:212. [PMID: 33761883 PMCID: PMC7992343 DOI: 10.1186/s12864-021-07478-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 02/24/2021] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND While nuclear transcription and RNA processing and localization are well established for protein coding genes (PCGs), these processes are poorly understood for long non-coding (lnc)RNAs. Here, we characterize global patterns of transcript expression, maturation and localization for mouse liver RNA, including more than 15,000 lncRNAs. PolyA-selected liver RNA was isolated and sequenced from four subcellular fractions (chromatin, nucleoplasm, total nucleus, and cytoplasm), and from the chromatin-bound fraction without polyA selection. RESULTS Transcript processing, determined from normalized intronic to exonic sequence read density ratios, progressively increased for PCG transcripts in going from the chromatin-bound fraction to the nucleoplasm and then on to the cytoplasm. Transcript maturation was similar for lncRNAs in the chromatin fraction, but was significantly lower in the nucleoplasm and cytoplasm. LncRNA transcripts were 11-fold more likely to be significantly enriched in the nucleus than cytoplasm, and 100-fold more likely to be significantly chromatin-bound than nucleoplasmic. Sequencing chromatin-bound RNA greatly increased the sensitivity for detecting lowly expressed lncRNAs and enabled us to discover and localize hundreds of novel regulated liver lncRNAs, including lncRNAs showing sex-biased expression or responsiveness to TCPOBOP a xenobiotic agonist ligand of constitutive androstane receptor (Nr1i3). CONCLUSIONS Integration of our findings with prior studies and lncRNA annotations identified candidate regulatory lncRNAs for a variety of hepatic functions based on gene co-localization within topologically associating domains or transcription divergent or antisense to PCGs associated with pathways linked to hepatic physiology and disease.
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Affiliation(s)
- Christine N Goldfarb
- Department of Biology and Bioinformatics Program, Boston University, 5 Cummington Mall, Boston, MA, 02215, USA
| | - David J Waxman
- Department of Biology and Bioinformatics Program, Boston University, 5 Cummington Mall, Boston, MA, 02215, USA.
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STAT5 Regulation of Sex-Dependent Hepatic CpG Methylation at Distal Regulatory Elements Mapping to Sex-Biased Genes. Mol Cell Biol 2021; 41:MCB.00166-20. [PMID: 33199496 DOI: 10.1128/mcb.00166-20] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 11/05/2020] [Indexed: 12/19/2022] Open
Abstract
Growth hormone-activated STAT5b is an essential regulator of sex-differential gene expression in mouse liver; however, its impact on hepatic gene expression and epigenetic responses is poorly understood. Here, we found a substantial, albeit incomplete loss of liver sex bias in hepatocyte-specific STAT5a/STAT5b (collectively, STAT5)-deficient mouse liver. In male liver, many male-biased genes were downregulated in direct association with the loss of STAT5 binding; many female-biased genes, which show low STAT5 binding, were derepressed, indicating an indirect mechanism for repression by STAT5. Extensive changes in CpG methylation were seen in STAT5-deficient liver, where sex differences were abolished at 88% of ∼1,500 sex-differentially methylated regions, largely due to increased DNA methylation upon STAT5 loss. STAT5-dependent CpG hypomethylation was rarely found at proximal promoters of STAT5-dependent genes. Rather, STAT5 primarily regulated the methylation of distal enhancers, where STAT5 deficiency induced widespread hypermethylation at genomic regions enriched for accessible chromatin, enhancer histone marks (histone H3 lysine 4 monomethylation [H3K4me1] and histone H3 lysine 27 acetylation [H3K27ac]), STAT5 binding, and DNA motifs for STAT5 and other transcription factors implicated in liver sex differences. Thus, the sex-dependent binding of STAT5 to liver chromatin is closely linked to the sex-dependent demethylation of distal regulatory elements linked to STAT5-dependent genes important for liver sex bias.
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Le Magueresse-Battistoni B. Adipose Tissue and Endocrine-Disrupting Chemicals: Does Sex Matter? INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17249403. [PMID: 33333918 PMCID: PMC7765367 DOI: 10.3390/ijerph17249403] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 12/10/2020] [Accepted: 12/14/2020] [Indexed: 12/21/2022]
Abstract
Obesity and metabolic-related diseases, among which diabetes, are prominent public health challenges of the 21st century. It is now well acknowledged that pollutants are a part of the equation, especially endocrine-disrupting chemicals (EDCs) that interfere with the hormonal aspect. The aim of the review is to focus on adipose tissue, a central regulator of energy balance and metabolic homeostasis, and to highlight the significant differences in the endocrine and metabolic aspects of adipose tissue between males and females which likely underlie the differences of the response to exposure to EDCs between the sexes. Moreover, the study also presents an overview of several mechanisms of action by which pollutants could cause adipose tissue dysfunction. Indeed, a better understanding of the mechanism by which environmental chemicals target adipose tissue and cause metabolic disturbances, and how these mechanisms interact and sex specificities are essential for developing mitigating and sex-specific strategies against metabolic diseases of chemical origin. In particular, considering that a scenario without pollutant exposure is not a realistic option in our current societies, attenuating the deleterious effects of exposure to pollutants by acting on the gut-adipose tissue axis may constitute a new direction of research.
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Affiliation(s)
- Brigitte Le Magueresse-Battistoni
- Univ-Lyon, CarMeN Laboratory, INSERM U1060, INRAé U1397, Université Claude Bernard Lyon1, F-69310 Pierre-Bénite, France; ; Tel.: +33-(0)-426235919; Fax: +33-(0)-426235916
- CarMeN Laboratory, INSERM U1060, Hopital Lyon-Sud, Bâtiment CENS ELI-2D, 165 Chemin du Grand Revoyet, 69310 Pierre-Bénite, France
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Melia T, Waxman DJ. Genetic factors contributing to extensive variability of sex-specific hepatic gene expression in Diversity Outbred mice. PLoS One 2020; 15:e0242665. [PMID: 33264334 PMCID: PMC7710091 DOI: 10.1371/journal.pone.0242665] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Accepted: 11/09/2020] [Indexed: 12/12/2022] Open
Abstract
Sex-specific transcription characterizes hundreds of genes in mouse liver, many implicated in sex-differential drug and lipid metabolism and disease susceptibility. While the regulation of liver sex differences by growth hormone-activated STAT5 is well established, little is known about autosomal genetic factors regulating the sex-specific liver transcriptome. Here we show, using genotyping and expression data from a large population of Diversity Outbred mice, that genetic factors work in tandem with growth hormone to control the individual variability of hundreds of sex-biased genes, including many long non-coding RNA genes. Significant associations between single nucleotide polymorphisms and sex-specific gene expression were identified as expression quantitative trait loci (eQTLs), many of which showed strong sex-dependent associations. Remarkably, autosomal genetic modifiers of sex-specific genes were found to account for more than 200 instances of gain or loss of sex-specificity across eight Diversity Outbred mouse founder strains. Sex-biased STAT5 binding sites and open chromatin regions with strain-specific variants were significantly enriched at eQTL regions regulating correspondingly sex-specific genes, supporting the proposed functional regulatory nature of the eQTL regions identified. Binding of the male-biased, growth hormone-regulated repressor BCL6 was most highly enriched at trans-eQTL regions controlling female-specific genes. Co-regulated gene clusters defined by overlapping eQTLs included sets of highly correlated genes from different chromosomes, further supporting trans-eQTL action. These findings elucidate how an unexpectedly large number of autosomal factors work in tandem with growth hormone signaling pathways to regulate the individual variability associated with sex differences in liver metabolism and disease.
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Affiliation(s)
- Tisha Melia
- Department of Biology and Bioinformatics Program, Boston University, Boston, Massachusetts, United States of America
| | - David J. Waxman
- Department of Biology and Bioinformatics Program, Boston University, Boston, Massachusetts, United States of America
- * E-mail:
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Xia W, Wang Y, Zhang Y, Ge X, Lv P, Cheng J, Wei J. Endoplasmic reticulum stress induces growth retardation by inhibiting growth hormone IGF-I axis. Growth Horm IGF Res 2020; 55:101341. [PMID: 32890915 DOI: 10.1016/j.ghir.2020.101341] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Revised: 08/10/2020] [Accepted: 08/11/2020] [Indexed: 12/25/2022]
Abstract
OBJECTIVE Insulin-like growth factor 1 (IGFI) is one of several growth factors which is induced by growth hormone (GH), which activates the Janus kinase 2 (JAK2)-signal transducer and activator of transcription 5 (STAT5) pathway, and plays crucial roles in normal human growth, metabolism, and systemic energy homeostasis. However, little is known about the negative regulation of IGF-I production under different physiological or pathological conditions. Herein, we explore whether activation of endoplasmic reticulum (ER) stress regulates IGF-I production and normal body growth. MATERIALS AND METHODS C57BL/6 J mice were challenged with tunicamycin (Tm) to induce ER stress activation. 24 h after stimulation, hepatic mRNA expression was analyzed by RNA-Seq and validated by qPCR. Enzyme-linked immunosorbent assay (ELISA) was performed 24 h after Tm stimulation. Body growth was determined 16 days after Tm stimulation. Animals were then sacrificed and liver tissues were collected for further analysis. RESULTS Mice challenged with Tm displayed a retardation of growth. Molecularly, we found that ER stress inhibited phosphorylation of STAT5. IGF-I transcription and circulating IGF-I were also dramatically decreased under ER stress activation. Moreover, our results demonstrate that IGF-I administration ameliorates Tm-induced growth retardation. CONCLUSIONS ER stress induces growth retardation. ER stress inhibits hepatic GH-JAK2 signaling activation and its downstream target gene expression. These results warrant further research to explore the crosstalk between ER stress and growth hormone signaling in improving body growth.
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Affiliation(s)
- Wanjun Xia
- Department of MRI, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China.
| | - Yajun Wang
- Department of Pediatrics, The First Affiliated Hospital of Harbin Medical University, Heilongjiang 150001, China
| | - Yong Zhang
- Department of MRI, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Xin Ge
- Department of Breast Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Pengwei Lv
- Department of Breast Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China
| | - Jingliang Cheng
- Department of MRI, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China.
| | - Juncheng Wei
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA.
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Buchmann GK, Schürmann C, Warwick T, Schulz MH, Spaeth M, Müller OJ, Schröder K, Jo H, Weissmann N, Brandes RP. Deletion of NoxO1 limits atherosclerosis development in female mice. Redox Biol 2020; 37:101713. [PMID: 32949971 PMCID: PMC7502371 DOI: 10.1016/j.redox.2020.101713] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Revised: 08/28/2020] [Accepted: 08/29/2020] [Indexed: 01/22/2023] Open
Abstract
OBJECTIVE Oxidative stress is a risk factor for atherosclerosis. NADPH oxidases of the Nox family produce ROS but their contribution to atherosclerosis development is less clear. Nox2 promotes and Nox4 rather limits atherosclerosis. Although Nox1 with its cytosolic co-factors are largely expressed in epithelial cells, a role for Nox1 for atherosclerosis development was suggested. To further define the role of this homologue, the role of its essential cytosolic cofactor, NoxO1, was determined for atherosclerosis development with the aid of knockout mice. METHODS AND RESULTS Wildtype (WT) and NoxO1 knockout mice were treated with high fat diet and adeno-associated virus (AAV) overexpressing pro-protein convertase subtilisin/kexin type 9 (PCSK9) to induce hepatic low-density lipoprotein (LDL) receptor loss. As a result, massive hypercholesterolemia was induced and spontaneous atherosclerosis developed within three month. Deletion of NoxO1 reduced atherosclerosis formation in brachiocephalic artery and aortic arch in female but not male NoxO1-/- mice as compared to WT littermates. This was associated with a reduced pro-inflammatory cytokine signature in the plasma of female but not male NoxO1-/- mice. MACE-RNAseq of the vessel did not reveal this signature and the expression of the Nox1/NoxO1 system was low to not detectable. CONCLUSIONS The scaffolding protein NoxO1 plays some role in atherosclerosis development in female mice probably by attenuating the global inflammatory burden.
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Affiliation(s)
- Giulia K Buchmann
- Institute for Cardiovascular Physiology, Goethe-University, Theodor-Stern Kai 7, 60590, Frankfurt Am Main, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Rhein Main, Theodor-Stern Kai 7, 60590, Frankfurt Am Main, Germany
| | - Christoph Schürmann
- Institute for Cardiovascular Physiology, Goethe-University, Theodor-Stern Kai 7, 60590, Frankfurt Am Main, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Rhein Main, Theodor-Stern Kai 7, 60590, Frankfurt Am Main, Germany
| | - Tim Warwick
- Institute for Cardiovascular Physiology, Goethe-University, Theodor-Stern Kai 7, 60590, Frankfurt Am Main, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Rhein Main, Theodor-Stern Kai 7, 60590, Frankfurt Am Main, Germany
| | - Marcel H Schulz
- German Center for Cardiovascular Research (DZHK), Partner Site Rhein Main, Theodor-Stern Kai 7, 60590, Frankfurt Am Main, Germany; Institute for Cardiovascular Regeneration, Goethe-University, Theodor-Stern Kai 7, 60590, Frankfurt Am Main, Germany
| | - Manuela Spaeth
- Institute for Cardiovascular Physiology, Goethe-University, Theodor-Stern Kai 7, 60590, Frankfurt Am Main, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Rhein Main, Theodor-Stern Kai 7, 60590, Frankfurt Am Main, Germany
| | - Oliver J Müller
- Department of Internal Medicine III, University of Kiel, Arnold-Heller-Straße 3, 24105, Kiel, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Hamburg/Kiel/Lübeck, Arnold-Heller-Straße 3, 24105, Kiel, Germany
| | - Katrin Schröder
- Institute for Cardiovascular Physiology, Goethe-University, Theodor-Stern Kai 7, 60590, Frankfurt Am Main, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Rhein Main, Theodor-Stern Kai 7, 60590, Frankfurt Am Main, Germany
| | - Hanjoong Jo
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, 313 Ferst Dr NW, Atlanta, GA, 30332, USA
| | - Norbert Weissmann
- Excellence Cluster Cardio-Pulmonary Institute (CPI), Universities of Giessen and Marburg Lung Center (UGMLC), Member of the German Center for Lung Research (DZL), Ludwigstraße 23, 35390, Gießen, Germany
| | - Ralf P Brandes
- Institute for Cardiovascular Physiology, Goethe-University, Theodor-Stern Kai 7, 60590, Frankfurt Am Main, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Rhein Main, Theodor-Stern Kai 7, 60590, Frankfurt Am Main, Germany.
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Della Torre S. Non-alcoholic Fatty Liver Disease as a Canonical Example of Metabolic Inflammatory-Based Liver Disease Showing a Sex-Specific Prevalence: Relevance of Estrogen Signaling. Front Endocrinol (Lausanne) 2020; 11:572490. [PMID: 33071979 PMCID: PMC7531579 DOI: 10.3389/fendo.2020.572490] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2020] [Accepted: 08/20/2020] [Indexed: 12/11/2022] Open
Abstract
There is extensive evidence supporting the interplay between metabolism and immune response, that have evolved in close relationship, sharing regulatory molecules and signaling systems, to support biological functions. Nowadays, the disruption of this interaction in the context of obesity and overnutrition underlies the increasing incidence of many inflammatory-based metabolic diseases, even in a sex-specific fashion. During evolution, the interplay between metabolism and reproduction has reached a degree of complexity particularly high in female mammals, likely to ensure reproduction only under favorable conditions. Several factors may account for differences in the incidence and progression of inflammatory-based metabolic diseases between females and males, thus contributing to age-related disease development and difference in life expectancy between the two sexes. Among these factors, estrogens, acting mainly through Estrogen Receptors (ERs), have been reported to regulate several metabolic pathways and inflammatory processes particularly in the liver, the metabolic organ showing the highest degree of sexual dimorphism. This review aims to investigate on the interaction between metabolism and inflammation in the liver, focusing on the relevance of estrogen signaling in counteracting the development and progression of non-alcoholic fatty liver disease (NAFLD), a canonical example of metabolic inflammatory-based liver disease showing a sex-specific prevalence. Understanding the role of estrogens/ERs in the regulation of hepatic metabolism and inflammation may provide the basis for the development of sex-specific therapeutic strategies for the management of such an inflammatory-based metabolic disease and its cardio-metabolic consequences.
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Affiliation(s)
- Sara Della Torre
- Department of Pharmaceutical Sciences, University of Milan, Milan, Italy
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39
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Matthews BJ, Waxman DJ. Impact of 3D genome organization, guided by cohesin and CTCF looping, on sex-biased chromatin interactions and gene expression in mouse liver. Epigenetics Chromatin 2020; 13:30. [PMID: 32680543 PMCID: PMC7368777 DOI: 10.1186/s13072-020-00350-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 07/03/2020] [Indexed: 12/13/2022] Open
Abstract
Several thousand sex-differential distal enhancers have been identified in mouse liver; however, their links to sex-biased genes and the impact of any sex-differences in nuclear organization and chromatin interactions are unknown. To address these issues, we first characterized 1847 mouse liver genomic regions showing significant sex differential occupancy by cohesin and CTCF, two key 3D nuclear organizing factors. These sex-differential binding sites were primarily distal to sex-biased genes but rarely generated sex-differential TAD (topologically associating domain) or intra-TAD loop anchors, and were sometimes found in TADs without sex-biased genes. A substantial subset of sex-biased cohesin-non-CTCF binding sites, but not sex-biased cohesin-and-CTCF binding sites, overlapped sex-biased enhancers. Cohesin depletion reduced the expression of male-biased genes with distal, but not proximal, sex-biased enhancers by >10-fold, implicating cohesin in long-range enhancer interactions regulating sex-biased genes. Using circularized chromosome conformation capture-based sequencing (4C-seq), we showed that sex differences in distal sex-biased enhancer-promoter interactions are common. Intra-TAD loops with sex-independent cohesin-and-CTCF anchors conferred sex specificity to chromatin interactions indirectly, by insulating sex-biased enhancer-promoter contacts and by bringing sex-biased genes into closer proximity to sex-biased enhancers. Furthermore, sex-differential chromatin interactions involving sex-biased gene promoters, enhancers, and lncRNAs were associated with sex-biased binding of cohesin and/or CTCF. These studies elucidate how 3D genome organization impacts sex-biased gene expression in a non-reproductive tissue through both direct and indirect effects of cohesin and CTCF looping on distal enhancer interactions with sex-differentially expressed genes.
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Affiliation(s)
- Bryan J Matthews
- Department of Biology and Bioinformatics Program, Boston University, 5 Cummington Mall, Boston, MA, 02215, USA
| | - David J Waxman
- Department of Biology and Bioinformatics Program, Boston University, 5 Cummington Mall, Boston, MA, 02215, USA.
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40
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Lau-Corona D, Bae WK, Hennighausen L, Waxman DJ. Sex-biased genetic programs in liver metabolism and liver fibrosis are controlled by EZH1 and EZH2. PLoS Genet 2020; 16:e1008796. [PMID: 32428001 PMCID: PMC7263639 DOI: 10.1371/journal.pgen.1008796] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 06/01/2020] [Accepted: 04/24/2020] [Indexed: 12/15/2022] Open
Abstract
Sex differences in the incidence and progression of many liver diseases, including liver fibrosis and hepatocellular carcinoma, are associated with sex-biased hepatic expression of hundreds of genes. This sexual dimorphism is largely determined by the sex-specific pattern of pituitary growth hormone secretion, which controls a transcriptional regulatory network operative in the context of sex-biased and growth hormone-regulated chromatin states. Histone H3K27-trimethylation yields a major sex-biased repressive chromatin mark deposited at many strongly female-biased genes in male mouse liver, but not at male-biased genes in female liver, and is catalyzed by polycomb repressive complex-2 through its homologous catalytic subunits, Ezh1 and Ezh2. Here, we used Ezh1-knockout mice with a hepatocyte-specific knockout of Ezh2 to investigate the sex bias of liver H3K27-trimethylation and its functional role in regulating sex-differences in the liver. Combined hepatic Ezh1/Ezh2 deficiency led to a significant loss of sex-biased gene expression, particularly in male liver, where many female-biased genes were increased in expression while male-biased genes showed decreased expression. The associated loss of H3K27me3 marks, and increases in the active enhancer marks H3K27ac and H3K4me1, were also more pronounced in male liver. Further, Ezh1/Ezh2 deficiency in male liver, and to a lesser extent in female liver, led to up regulation of many genes linked to liver fibrosis and liver cancer, which may contribute to the observed liver pathologies and the increased sensitivity of these mice to hepatotoxin exposure. Thus, Ezh1/Ezh2-catalyzed H3K27-trimethyation regulates sex-dependent genetic programs in liver metabolism and liver fibrosis through its sex-dependent effects on the epigenome, and may thereby determine the sex-bias in liver disease susceptibility. Sex-differences in the expression of genes in liver have a direct impact on liver diseases whose incidence and severity is sex-biased, and is controlled by hormones that regulate chemical alterations to histone proteins used to package chromosomal DNA. However, a direct demonstration of the functional importance of such sex differences in histone protein modifications has been elusive. Here, we address this question using a mouse model deficient in two enzymes, Ezh1/Ezh2, which generate the histone repressive mark H3K27me3. Remarkably, although H3K27me3 marks are formed by Ezh1/Ezh2 throughout the genome, loss of liver Ezh1/Ezh2 preferentially disrupts the control of sex-biased genes, with expression increasing in male mouse liver for many female-biased genes and decreasing for many male-biased genes. Sex-biased H3K27me3 repressive marks were abolished, and there was a gain of active histone marks at gene enhancers. We also found increased expression of many genes associated with liver fibrosis and hepatocellular carcinoma, which may help explain the increased sensitivity of Ezh1/Ezh2-deficient livers to hepatotoxic chemicals whose exposure may lead to sex differences in liver disease incidence and susceptibility. Thus, our findings highlight the potential role of sex differences in histone modifications catalyzed by Ezh1/Ezh2 in widespread sex differences in liver diseases.
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Affiliation(s)
- Dana Lau-Corona
- Department of Biology and Bioinformatics Program, Boston University, Boston, Massachusetts, United States of America
| | - Woo Kyun Bae
- Laboratory of Genetics and Physiology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
- Department of Internal Medicine, Chonnam National University Medical School, Gwangju, Korea
| | - Lothar Hennighausen
- Laboratory of Genetics and Physiology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - David J. Waxman
- Department of Biology and Bioinformatics Program, Boston University, Boston, Massachusetts, United States of America
- * E-mail:
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Abstract
Growth hormone (GH) plays a pivotal role in many physiological processes in humans, and in other mammalian and non-mammalian vertebrate species, through actions on somatic growth, tissue development and repair, and intermediary metabolism. This review will focus on mechanisms of GH actions on gene expression, primarily from the perspective of the genes that encode proteins stimulated by GH to regulate somatic growth, especially insulin-like growth factor 1 (IGF-I), but also others that are induced or repressed by GH. Topics to be discussed will include a brief overview of GH-mediated signal transduction pathways and how these cascades alter the functions of responsive transcription factors, with a specific focus on STAT5B, a key member of the signal transducers and activators of transcription family, characterization of essential GH-regulated genes, and elucidation of mechanisms of their regulation from biochemical, genetic, and genomic perspectives.
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Affiliation(s)
- Peter Rotwein
- Department of Molecular and Translational Medicine, Paul L. Foster School of Medicine, Texas Tech Health University Health Sciences Center, El Paso, TX, 79905, USA.
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Summers KM, Bush SJ, Wu C, Su AI, Muriuki C, Clark EL, Finlayson HA, Eory L, Waddell LA, Talbot R, Archibald AL, Hume DA. Functional Annotation of the Transcriptome of the Pig, Sus scrofa, Based Upon Network Analysis of an RNAseq Transcriptional Atlas. Front Genet 2020; 10:1355. [PMID: 32117413 PMCID: PMC7034361 DOI: 10.3389/fgene.2019.01355] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 12/11/2019] [Indexed: 12/15/2022] Open
Abstract
The domestic pig (Sus scrofa) is both an economically important livestock species and a model for biomedical research. Two highly contiguous pig reference genomes have recently been released. To support functional annotation of the pig genomes and comparative analysis with large human transcriptomic data sets, we aimed to create a pig gene expression atlas. To achieve this objective, we extended a previous approach developed for the chicken. We downloaded RNAseq data sets from public repositories, down-sampled to a common depth, and quantified expression against a reference transcriptome using the mRNA quantitation tool, Kallisto. We then used the network analysis tool Graphia to identify clusters of transcripts that were coexpressed across the merged data set. Consistent with the principle of guilt-by-association, we identified coexpression clusters that were highly tissue or cell-type restricted and contained transcription factors that have previously been implicated in lineage determination. Other clusters were enriched for transcripts associated with biological processes, such as the cell cycle and oxidative phosphorylation. The same approach was used to identify coexpression clusters within RNAseq data from multiple individual liver and brain samples, highlighting cell type, process, and region-specific gene expression. Evidence of conserved expression can add confidence to assignment of orthology between pig and human genes. Many transcripts currently identified as novel genes with ENSSSCG or LOC IDs were found to be coexpressed with annotated neighbouring transcripts in the same orientation, indicating they may be products of the same transcriptional unit. The meta-analytic approach to utilising public RNAseq data is extendable to include new data sets and new species and provides a framework to support the Functional Annotation of Animals Genomes (FAANG) initiative.
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Affiliation(s)
- Kim M. Summers
- Mater Research Institute-University of Queensland, Translational Research Institute, Woolloongabba, QLD, Australia
| | - Stephen J. Bush
- Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
| | - Chunlei Wu
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, United States
| | - Andrew I. Su
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, United States
| | - Charity Muriuki
- The Roslin Institute, University of Edinburgh, Midlothian, United Kingdom
| | - Emily L. Clark
- The Roslin Institute, University of Edinburgh, Midlothian, United Kingdom
| | | | - Lel Eory
- The Roslin Institute, University of Edinburgh, Midlothian, United Kingdom
| | - Lindsey A. Waddell
- The Roslin Institute, University of Edinburgh, Midlothian, United Kingdom
| | - Richard Talbot
- The Roslin Institute, University of Edinburgh, Midlothian, United Kingdom
| | - Alan L. Archibald
- The Roslin Institute, University of Edinburgh, Midlothian, United Kingdom
| | - David A. Hume
- Mater Research Institute-University of Queensland, Translational Research Institute, Woolloongabba, QLD, Australia
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Pillman KA, Scheer KG, Hackett-Jones E, Saunders K, Bert AG, Toubia J, Whitfield HJ, Sapkota S, Sourdin L, Pham H, Le TD, Cursons J, Davis MJ, Gregory PA, Goodall GJ, Bracken CP. Extensive transcriptional responses are co-ordinated by microRNAs as revealed by Exon-Intron Split Analysis (EISA). Nucleic Acids Res 2019; 47:8606-8619. [PMID: 31372646 PMCID: PMC6895270 DOI: 10.1093/nar/gkz664] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 07/16/2019] [Accepted: 07/30/2019] [Indexed: 12/29/2022] Open
Abstract
Epithelial-mesenchymal transition (EMT) has been a subject of intense scrutiny as it facilitates metastasis and alters drug sensitivity. Although EMT-regulatory roles for numerous miRNAs and transcription factors are known, their functions can be difficult to disentangle, in part due to the difficulty in identifying direct miRNA targets from complex datasets and in deciding how to incorporate 'indirect' miRNA effects that may, or may not, represent biologically relevant information. To better understand how miRNAs exert effects throughout the transcriptome during EMT, we employed Exon-Intron Split Analysis (EISA), a bioinformatic technique that separates transcriptional and post-transcriptional effects through the separate analysis of RNA-Seq reads mapping to exons and introns. We find that in response to the manipulation of miRNAs, a major effect on gene expression is transcriptional. We also find extensive co-ordination of transcriptional and post-transcriptional regulatory mechanisms during both EMT and mesenchymal to epithelial transition (MET) in response to TGF-β or miR-200c respectively. The prominent transcriptional influence of miRNAs was also observed in other datasets where miRNA levels were perturbed. This work cautions against a narrow approach that is limited to the analysis of direct targets, and demonstrates the utility of EISA to examine complex regulatory networks involving both transcriptional and post-transcriptional mechanisms.
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Affiliation(s)
- Katherine A Pillman
- Centre for Cancer Biology, an alliance of SA Pathology and University of South Australia, Adelaide, SA, Australia.,ACRF Cancer Genomics Facility, Centre for Cancer Biology, SA Pathology, Adelaide, Australia
| | - Kaitlin G Scheer
- Centre for Cancer Biology, an alliance of SA Pathology and University of South Australia, Adelaide, SA, Australia
| | - Emily Hackett-Jones
- Centre for Cancer Biology, an alliance of SA Pathology and University of South Australia, Adelaide, SA, Australia
| | - Klay Saunders
- Centre for Cancer Biology, an alliance of SA Pathology and University of South Australia, Adelaide, SA, Australia
| | - Andrew G Bert
- Centre for Cancer Biology, an alliance of SA Pathology and University of South Australia, Adelaide, SA, Australia
| | - John Toubia
- Centre for Cancer Biology, an alliance of SA Pathology and University of South Australia, Adelaide, SA, Australia.,ACRF Cancer Genomics Facility, Centre for Cancer Biology, SA Pathology, Adelaide, Australia
| | - Holly J Whitfield
- Bioinformatics Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
| | - Sunil Sapkota
- Centre for Cancer Biology, an alliance of SA Pathology and University of South Australia, Adelaide, SA, Australia
| | - Laura Sourdin
- Centre for Cancer Biology, an alliance of SA Pathology and University of South Australia, Adelaide, SA, Australia
| | - Hoang Pham
- School of Information Technology and Mathematical Sciences, University of South Australia, Mawson Lakes, SA, Australia
| | - Thuc D Le
- School of Information Technology and Mathematical Sciences, University of South Australia, Mawson Lakes, SA, Australia
| | - Joseph Cursons
- School of Information Technology and Mathematical Sciences, University of South Australia, Mawson Lakes, SA, Australia.,Department of Medical Biology, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, Victoria, Australia
| | - Melissa J Davis
- School of Information Technology and Mathematical Sciences, University of South Australia, Mawson Lakes, SA, Australia.,Department of Medical Biology, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, Victoria, Australia.,Department of Biochemistry, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, Victoria, Australia
| | - Philip A Gregory
- Centre for Cancer Biology, an alliance of SA Pathology and University of South Australia, Adelaide, SA, Australia.,School of Medicine, Discipline of Medicine, University of Adelaide, SA, Australia
| | - Gregory J Goodall
- Centre for Cancer Biology, an alliance of SA Pathology and University of South Australia, Adelaide, SA, Australia.,School of Medicine, Discipline of Medicine, University of Adelaide, SA, Australia
| | - Cameron P Bracken
- Centre for Cancer Biology, an alliance of SA Pathology and University of South Australia, Adelaide, SA, Australia.,School of Medicine, Discipline of Medicine, University of Adelaide, SA, Australia
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44
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Huang L, Huang Z, Chen C. Rhythmic growth hormone secretion in physiological and pathological conditions: Lessons from rodent studies. Mol Cell Endocrinol 2019; 498:110575. [PMID: 31499134 DOI: 10.1016/j.mce.2019.110575] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 09/04/2019] [Accepted: 09/04/2019] [Indexed: 02/01/2023]
Abstract
Evolutionally conserved in all mammalians, the release of GH occurs in a rhythmic pattern, characterized by several dominant surges (pulsatile GH) with tonic low inter-pulse levels (tonic GH). Such pulsatile secretion pattern is essential for many physiological actions of GH on different tissues with defined gender dimorphism. Rhythmic release of pulsatile GH is tightly controlled by hypothalamic neurons as well as peripheral metabolic factors. Changes of GH pattern occur within a range of sophisticated physiological and pathological settings and significantly contribute to growth, ageing, survival and disease predispositions. Precise analysis of GH secretion pattern is vitally important for a comprehensive understanding of the function of GH and the components that regulate GH secretion pattern.
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Affiliation(s)
- Lili Huang
- School of Biomedical Sciences, University of Queensland, St Lucia, Brisbane, Australia
| | - Zhengxiang Huang
- School of Biomedical Sciences, University of Queensland, St Lucia, Brisbane, Australia
| | - Chen Chen
- School of Biomedical Sciences, University of Queensland, St Lucia, Brisbane, Australia.
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45
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Bacigalupo ML, Piazza VG, Cicconi NS, Carabias P, Bartke A, Fang Y, Sotelo AI, Rabinovich GA, Troncoso MF, Miquet JG. Growth hormone upregulates the pro-tumorigenic galectin 1 in mouse liver. Endocr Connect 2019; 8:1108-1117. [PMID: 31272083 PMCID: PMC6652241 DOI: 10.1530/ec-19-0292] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 07/04/2019] [Indexed: 12/24/2022]
Abstract
Transgenic mice overexpressing growth hormone (GH) spontaneously develop liver tumors, including hepatocellular carcinoma (HCC), within a year. The preneoplastic liver pathology in these mice recapitulates that observed in humans at high risk of developing hepatic cancer. Although increased expression of galectin 1 (GAL1) in liver tissue is associated with HCC aggressiveness, a link between this glycan-binding protein and hormone-related tumor development has not yet been explored. In this study, we investigated GAL1 expression during liver tumor progression in mice continuously exposed to high levels of GH. GAL1 expression was determined by Western blotting, RT-qPCR and immunohistochemistry in the liver of transgenic mice overexpressing GH. Animals of representative ages at different stages of liver pathology were studied. GAL1 expression was upregulated in the liver of GH-transgenic mice. This effect was observed at early ages, when animals displayed no signs of liver disease or minimal histopathological alterations and was also detected in young adults with preneoplastic liver pathology. Remarkably, GAL1 upregulation was sustained during aging and its expression was particularly enhanced in liver tumors. GH also induced hepatic GAL1 expression in mice that were treated with this hormone for a short period. Moreover, GH triggered a rapid increment in GAL1 protein expression in human HCC cells, denoting a direct effect of the hormone on hepatocytes. Therefore, our results indicate that GH upregulates GAL1 expression in mouse liver, which may have critical implications in tumorigenesis. These findings suggest that this lectin could be implicated in hormone-driven liver carcinogenesis.
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Affiliation(s)
- María L Bacigalupo
- Departamento de Química Biológica, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Química y Fisicoquímica Biológicas, Buenos Aires, Argentina
| | - Verónica G Piazza
- Departamento de Química Biológica, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Química y Fisicoquímica Biológicas, Buenos Aires, Argentina
| | - Nadia S Cicconi
- Departamento de Química Biológica, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Química y Fisicoquímica Biológicas, Buenos Aires, Argentina
| | - Pablo Carabias
- Departamento de Química Biológica, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Química y Fisicoquímica Biológicas, Buenos Aires, Argentina
| | - Andrzej Bartke
- Department of Internal Medicine, Geriatrics Research, Southern Illinois University School of Medicine, Springfield, Illinois, USA
| | - Yimin Fang
- Department of Internal Medicine, Geriatrics Research, Southern Illinois University School of Medicine, Springfield, Illinois, USA
| | - Ana I Sotelo
- Departamento de Química Biológica, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Química y Fisicoquímica Biológicas, Buenos Aires, Argentina
| | - Gabriel A Rabinovich
- Laboratorio de Inmunopatología, Instituto de Biología y Medicina Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas, and Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - María F Troncoso
- Departamento de Química Biológica, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Química y Fisicoquímica Biológicas, Buenos Aires, Argentina
- Correspondence should be addressed to M F Troncoso or J G Miquet: or
| | - Johanna G Miquet
- Departamento de Química Biológica, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Instituto de Química y Fisicoquímica Biológicas, Buenos Aires, Argentina
- Correspondence should be addressed to M F Troncoso or J G Miquet: or
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46
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Dias C, Elzein S, Sladek R, Goodyer CG. Sex-specific effects of a microsatellite polymorphism on human growth hormone receptor gene expression. Mol Cell Endocrinol 2019; 492:110442. [PMID: 31063794 DOI: 10.1016/j.mce.2019.05.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 05/02/2019] [Accepted: 05/03/2019] [Indexed: 01/05/2023]
Abstract
Growth hormone (GH) binds to its specific receptor (GHR) at the surface of target cells activating multiple signaling pathways implicated in growth and metabolism. Dysregulation of GHRs leads to pathophysiological states that most commonly affect stature. We previously showed the association of a polymorphic (n = 15-37) GT microsatellite in the human GHR gene promoter with short stature in a sex-specific manner. In the present study we evaluated the functional relevance of this polymorphism in regulating GHR expression. Using luciferase reporter assays, we found that the GT repeat had a significant cis regulatory effect in response to HIF1α and a potential repressor role following C/EBPβ stimulation. Using a digital PCR application to measure allelic imbalance (AI), we showed a high prevalence of AI (∼76%) at the GHR locus in lymphoblastoid cell lines (LCLs), with a significantly higher degree of imbalance in LCLs derived from males. Examination of expression of GHR as well as other members of the GH-IGF1 axis in the LCLs revealed significant associations of GHR, IGF1 and BCL2 expression with GT genotype in a sex-specific manner. Our results suggest that this GT microsatellite exerts both cis and trans effects in a sex-specific context, revealing a new mechanism by which GHR gene expression is regulated.
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Affiliation(s)
- Christel Dias
- Division of Experimental Medicine, McGill University, Montreal, Quebec, H4A 3J1, Canada
| | - Samar Elzein
- Division of Experimental Medicine, McGill University, Montreal, Quebec, H4A 3J1, Canada
| | - Robert Sladek
- Division of Experimental Medicine and Department of Human Genetics, McGill University, Montreal, Quebec, H4A 3J1, Canada
| | - Cynthia Gates Goodyer
- Division of Experimental Medicine and Department of Pediatrics, McGill University, Montreal, Quebec, H4A 3J1, Canada.
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47
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Lodato NJ, Rampersaud A, Waxman DJ. Impact of CAR Agonist Ligand TCPOBOP on Mouse Liver Chromatin Accessibility. Toxicol Sci 2019; 164:115-128. [PMID: 29617930 DOI: 10.1093/toxsci/kfy070] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Activation of the nuclear receptor and transcription factor CAR (Nr1i3) by its specific agonist ligand TCPOBOP (1, 4-bis[2-(3, 5-dichloropyridyloxy)]benzene) dysregulates hundreds of genes in mouse liver and is linked to male-biased hepatocarcinogenesis. To elucidate the genomic organization of CAR-induced gene responses, we investigated the distribution of TCPOBOP-responsive RefSeq coding and long noncoding RNA (lncRNA) genes across the megabase-scale topologically associating domains (TADs) that segment the genome, and which provide a structural framework that functionally constrains enhancer-promoter interactions. We show that a subset of TCPOBOP-responsive genes cluster within TADs, and that TCPOBOP-induced genes and TCPOBOP-repressed genes are often found in different TADs. Further, using DNase-seq and DNase hypersensitivity site (DHS) analysis, we identified several thousand genomic regions (ΔDHS) where short-term exposure to TCPOBOP induces localized changes (increases or decreases) in mouse liver chromatin accessibility, many of which cluster in TADs together with TCPOBOP-responsive genes. Sites of chromatin opening were highly enriched nearby genes induced by TCPOBOP and chromatin closing was highly enriched nearby genes repressed by TCPOBOP, consistent with TCPOBOP-responsive ΔDHS serving as enhancers and promoters that positively regulate CAR-responsive genes. Gene expression changes lagged behind chromatin opening or closing for a subset of TCPOBOP-responsive ΔDHS. ΔDHS that were specifically responsive to TCPOBOP in male liver were significantly enriched for genomic regions with a basal male bias in chromatin accessibility; however, the male-biased response of hepatocellular carcinoma-related genes to TCPOBOP was not associated with a correspondingly male-biased ΔDHS response. These studies elucidate the genome-wide organization of CAR-responsive genes and of the thousands of associated genomic sites where TCPOBOP exposure induces both rapid and persistent changes in chromatin accessibility.
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Affiliation(s)
- Nicholas J Lodato
- Department of Biology and Bioinformatics Program, Boston University, Boston, Massachusetts 02215
| | - Andy Rampersaud
- Department of Biology and Bioinformatics Program, Boston University, Boston, Massachusetts 02215
| | - David J Waxman
- Department of Biology and Bioinformatics Program, Boston University, Boston, Massachusetts 02215
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48
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Melia T, Waxman DJ. Sex-Biased lncRNAs Inversely Correlate With Sex-Opposite Gene Coexpression Networks in Diversity Outbred Mouse Liver. Endocrinology 2019; 160:989-1007. [PMID: 30840070 PMCID: PMC6449536 DOI: 10.1210/en.2018-00949] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 02/27/2019] [Indexed: 01/05/2023]
Abstract
Sex differences in liver gene expression are determined by pituitary growth hormone secretion patterns, which regulate sex-dependent liver transcription factors and establish sex-specific chromatin states. Hypophysectomy (hypox) identifies two major classes of liver sex-biased genes, defined by their sex-dependent positive or negative responses to pituitary hormone ablation. However, the mechanisms that underlie each hypox-response class are unknown. We sought to discover candidate, regulatory, long noncoding RNAs (lncRNAs) controlling responsiveness to hypox. We characterized gene structures and expression patterns for 15,558 mouse liver-expressed lncRNAs, including many sex-specific lncRNAs regulated during postnatal development or subject to circadian regulation. Using the high natural allelic variance of Diversity Outbred (DO) mice, we discovered tightly coexpressed clusters of sex-specific protein-coding genes (gene modules) in male and female DO liver. Remarkably, many gene modules were strongly enriched for sex-specific genes within a single hypox-response class, indicating that the genetic heterogeneity of DO mice encompasses responsiveness to hypox. Moreover, several distant gene modules were enriched for gene subsets of the same hypox-response class, highlighting the complex regulation of hypox-responsiveness. Finally, we identified eight sex-specific lncRNAs with strong negative regulatory potential, as indicated by their strong negative correlation of expression across DO mouse livers with that of protein-coding gene modules enriched for genes of the opposite sex bias and inverse hypox-response class. These findings reveal an important role for genetic factors in regulating responsiveness to hypox, and present testable hypotheses for the roles of sex-biased liver lncRNAs in controlling the sex-bias of liver gene expression.
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Affiliation(s)
- Tisha Melia
- Department of Biology and Bioinformatics Program, Boston University, Boston, Massachusetts
| | - David J Waxman
- Department of Biology and Bioinformatics Program, Boston University, Boston, Massachusetts
- Correspondence: David J. Waxman, PhD, Department of Biology, Boston University, 5 Cummington Mall, Boston, Massachusetts 02215. E-mail:
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49
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Brain Control of Sexually Dimorphic Liver Function and Disease: The Endocrine Connection. Cell Mol Neurobiol 2019; 39:169-180. [DOI: 10.1007/s10571-019-00652-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 01/10/2019] [Indexed: 12/27/2022]
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50
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Dosage compensation and DNA methylation landscape of the X chromosome in mouse liver. Sci Rep 2018; 8:10138. [PMID: 29973619 PMCID: PMC6031675 DOI: 10.1038/s41598-018-28356-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 06/18/2018] [Indexed: 01/01/2023] Open
Abstract
DNA methylation plays a key role in X-chromosome inactivation (XCI), a process that achieves dosage compensation for X-encoded gene products between mammalian female and male cells. However, differential sex chromosome dosage complicates genome-wide epigenomic assessments, and the X chromosome is frequently excluded from female-to-male comparative analyses. Using the X chromosome in the sexually dimorphic mouse liver as a model, we provide a general framework for comparing base-resolution DNA methylation patterns across samples that have different chromosome numbers and ask at a systematic level if predictions by historical analyses of X-linked DNA methylation hold true at a base-resolution chromosome-wide level. We demonstrate that sex-specific methylation patterns on the X chromosome largely reflect the effects of XCI. While our observations concur with longstanding observations of XCI at promoter-proximal CpG islands, we provide evidence that sex-specific DNA methylation differences are not limited to CpG island boundaries. Moreover, these data support a model in which maintenance of CpG islands in the inactive state does not require complete regional methylation. Further, we validate an intragenic non-CpG methylation signature in genes escaping XCI in mouse liver. Our analyses provide insight into underlying methylation patterns that should be considered when assessing sex differences in genome-wide methylation analyses.
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