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Wang F, Mehta P, Bach I. How does the Xist activator Rlim/Rnf12 regulate Xist expression? Biochem Soc Trans 2024; 52:1099-1107. [PMID: 38747697 PMCID: PMC11346418 DOI: 10.1042/bst20230573] [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] [Received: 01/25/2024] [Revised: 05/01/2024] [Accepted: 05/02/2024] [Indexed: 05/23/2024]
Abstract
The long non-coding RNA (lncRNA) Xist is crucially involved in a process called X chromosome inactivation (XCI), the transcriptional silencing of one of the two X chromosomes in female mammals to achieve X dosage compensation between the sexes. Because Xist RNA silences the X chromosome from which it is transcribed, the activation of Xist transcription marks the initiation of the XCI process and thus, mechanisms and players that activate this gene are of central importance to the XCI process. During female mouse embryogenesis, XCI occurs in two steps. At the 2-4 cell stages imprinted XCI (iXCI) silences exclusively the paternally inherited X chromosome (Xp). While extraembryonic cells including trophoblasts keep the Xp silenced, epiblast cells that give rise to the embryo proper reactivate the Xp and undergo random XCI (rXCI) around implantation. Both iXCI and rXCI are dependent on Xist. Rlim, also known as Rnf12, is an X-linked E3 ubiquitin ligase that is involved in the transcriptional activation of Xist. However, while data on the crucial involvement of Rlim during iXCI appear clear, its role in rXCI has been controversial. This review discusses data leading to this disagreement and recent evidence for a regulatory switch of Xist transcription in epiblasts of implanting embryos, partially reconciling the roles of Rlim during Xist activation.
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Affiliation(s)
- Feng Wang
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Chan Medical School, Worcester, MA 01605, U.S.A
| | - Poonam Mehta
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Chan Medical School, Worcester, MA 01605, U.S.A
| | - Ingolf Bach
- Department of Molecular, Cell and Cancer Biology, University of Massachusetts Chan Medical School, Worcester, MA 01605, U.S.A
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Leithy AAE, Bakr YM, Hassan NM, Dardeer KT, Assem M, Wahab AHAA. PTCSC3, XIST, GAS5, UCA1, and HIFAL: Five lncRNAs Emerging as Potential Prognostic Players in Egyptian Adult Acute Myeloid Leukemia (AML) Patients. Cancer Control 2024; 31:10732748241309044. [PMID: 39673539 DOI: 10.1177/10732748241309044] [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] [Indexed: 12/16/2024] Open
Abstract
BACKGROUND AND AIMS So far, long noncoding RNAs (lncRNAs) signatures in acute myeloid leukemia (AML) are poorly understood. The present study aims to explore the prognostic significance of eleven cancer-related lncRNAs in bone marrow (BM) samples from adult Egyptian AML patients. MATERIALS AND METHODS In this study, we analyzed eleven lncRNAs using the qRT-PCR assay in the bone marrow (BM) of 79 de novo AML adult patients before receiving any therapy. RESULTS Five lncRNAs out of 11 were aberrantly expressed, and two lncRNAs influenced significantly the patient's overall survival (OS). LncRNA-XIST was favorable when overexpressed (in univariate and multivariate analysis, P-value = .001). LncRNA-GAS5 adversely affected the OS (only in multivariate analysis P-value = .02). Two other lncRNAs (UCA1 and HIFAL) impacted complete remission induction (CR) significantly in univariate analysis (P-value = .046 for both). Furthermore, lncRNA-UCA1 affected CR significantly in multivariate COX regression analysis (P-value = .004). The 4 previously mentioned lncRNAs were among the 9 downregulated lncRNAs. Instead, the only 2 upregulated lncRNAs (SNHG15, MALAT1) did not significantly influence neither CR induction nor OS. LncRNA-PTCSC3, a fifth lncRNA, emerged as the only one that could predict relapse occurrence in an upfront original BM sample. CONCLUSION Two lncRNAs out of eleven (lncRNA-XIST and GAS5) impacted OS, and two other lncRNAs (UCA1 and HIFAL) affected CR in adult de novo AML patients. LncRNA-PTCSC3 predict relapse, however, further validation is still required.
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Affiliation(s)
- Asmaa A El Leithy
- College of Biotechnology, Misr University for Science and Technology (MUST), Giza, Egypt
| | - Yasser Mabrouk Bakr
- Cancer Biology Department, National Cancer Institute, Cairo University, Cairo, Egypt
| | - Naglaa M Hassan
- Clinical Pathology Department, National Cancer Institute, Cairo University, Cairo, Egypt
| | | | - Magda Assem
- Clinical Pathology Department, National Cancer Institute, Cairo University, Cairo, Egypt
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Zaher K, Basingab F, Alrahimi J, Basahel K, Aldahlawi A. Gender Differences in Response to COVID-19 Infection and Vaccination. Biomedicines 2023; 11:1677. [PMID: 37371774 DOI: 10.3390/biomedicines11061677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2023] [Revised: 06/04/2023] [Accepted: 06/05/2023] [Indexed: 06/29/2023] Open
Abstract
Since COVID-19 first appeared, a number of follow-up events have taken place. In an effort to find a solution to this catastrophe, a great deal of study and analysis has been conducted. Because of the high morbidity and exceptionally large losses, scientists are being pushed to conduct more research and find vaccination and treatments. The virus has a wide range of effects, one of which is how it affects sexual activity in both men and women. The impact of the cardiovascular system and susceptibility to embolism, lung stress, and infection heightens the probability of hospitalization in the intensive care unit for pregnant women who have contracted COVID-19. There is no evidence of infection being passed from mother to child. In the current review, the role of COVID-19 infection and vaccination on male and female sexual activity, hormones, and the menstrual cycle for females, as well as on male sex hormones and sexual activity during infection and after vaccination, are being investigated. There are no reports of the virus being isolated from the semen of an infected patient or recently recovered patients. A recent investigation on the influence of the virus on gender susceptibility to sexual organs and function has been uncovered throughout this study.
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Affiliation(s)
- Kawther Zaher
- Immunology Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21859, Saudi Arabia
- Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah 21859, Saudi Arabia
| | - Fatemah Basingab
- Department of Biological Sciences, Faculty of Sciences, King Abdulaziz University, Jeddah 21859, Saudi Arabia
- Immunology Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21859, Saudi Arabia
| | - Jehan Alrahimi
- Department of Biological Sciences, Faculty of Sciences, King Abdulaziz University, Jeddah 21859, Saudi Arabia
- Immunology Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21859, Saudi Arabia
| | - Kholood Basahel
- Department of Biological Sciences, Faculty of Sciences, King Abdulaziz University, Jeddah 21859, Saudi Arabia
- Immunology Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21859, Saudi Arabia
| | - Alia Aldahlawi
- Department of Biological Sciences, Faculty of Sciences, King Abdulaziz University, Jeddah 21859, Saudi Arabia
- Immunology Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21859, Saudi Arabia
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4
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Richardson V, Engel N, Kulathinal RJ. Comparative developmental genomics of sex-biased gene expression in early embryogenesis across mammals. Biol Sex Differ 2023; 14:30. [PMID: 37208698 DOI: 10.1186/s13293-023-00520-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 05/15/2023] [Indexed: 05/21/2023] Open
Abstract
BACKGROUND Mammalian gonadal sex is determined by the presence or absence of a Y chromosome and the subsequent production of sex hormones contributes to secondary sexual differentiation. However, sex chromosome-linked genes encoding dosage-sensitive transcription and epigenetic factors are expressed well before gonad formation and have the potential to establish sex-biased expression that persists beyond the appearance of gonadal hormones. Here, we apply a comparative bioinformatics analysis on a pair of published single-cell datasets from mouse and human during very early embryogenesis-from two-cell to pre-implantation stages-to characterize sex-specific signals and to assess the degree of conservation among early acting sex-specific genes and pathways. RESULTS Clustering and regression analyses of gene expression across samples reveal that sex initially plays a significant role in overall gene expression patterns at the earliest stages of embryogenesis which potentially may be the byproduct of signals from male and female gametes during fertilization. Although these transcriptional sex effects rapidly diminish, sex-biased genes appear to form sex-specific protein-protein interaction networks across pre-implantation stages in both mammals providing evidence that sex-biased expression of epigenetic enzymes may establish sex-specific patterns that persist beyond pre-implantation. Non-negative matrix factorization (NMF) on male and female transcriptomes generated clusters of genes with similar expression patterns across sex and developmental stages, including post-fertilization, epigenetic, and pre-implantation ontologies conserved between mouse and human. While the fraction of sex-differentially expressed genes (sexDEGs) in early embryonic stages is similar and functional ontologies are conserved, the genes involved are generally different in mouse and human. CONCLUSIONS This comparative study uncovers much earlier than expected sex-specific signals in mouse and human embryos that pre-date hormonal signaling from the gonads. These early signals are diverged with respect to orthologs yet conserved in terms of function with important implications in the use of genetic models for sex-specific disease.
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Affiliation(s)
- Victorya Richardson
- Department of Biology, Temple University, 1900 N. 12th Street, Philadelphia, PA, 19122, USA
| | - Nora Engel
- Department of Cancer Biology, Lewis Katz School of Medicine, Fels Cancer Institute for Personalized Medicine, Temple University, 3400 N. Broad Street, Philadelphia, PA, 19140, USA.
| | - Rob J Kulathinal
- Department of Biology, Temple University, 1900 N. 12th Street, Philadelphia, PA, 19122, USA.
- Institute for Genomics and Evolutionary Medicine, Temple University, Philadelphia, PA, 19122, USA.
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5
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Marcogliese PC, Deal SL, Andrews J, Harnish JM, Bhavana VH, Graves HK, Jangam S, Luo X, Liu N, Bei D, Chao YH, Hull B, Lee PT, Pan H, Bhadane P, Huang MC, Longley CM, Chao HT, Chung HL, Haelterman NA, Kanca O, Manivannan SN, Rossetti LZ, German RJ, Gerard A, Schwaibold EMC, Fehr S, Guerrini R, Vetro A, England E, Murali CN, Barakat TS, van Dooren MF, Wilke M, van Slegtenhorst M, Lesca G, Sabatier I, Chatron N, Brownstein CA, Madden JA, Agrawal PB, Keren B, Courtin T, Perrin L, Brugger M, Roser T, Leiz S, Mau-Them FT, Delanne J, Sukarova-Angelovska E, Trajkova S, Rosenhahn E, Strehlow V, Platzer K, Keller R, Pavinato L, Brusco A, Rosenfeld JA, Marom R, Wangler MF, Yamamoto S. Drosophila functional screening of de novo variants in autism uncovers damaging variants and facilitates discovery of rare neurodevelopmental diseases. Cell Rep 2022; 38:110517. [PMID: 35294868 PMCID: PMC8983390 DOI: 10.1016/j.celrep.2022.110517] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 09/23/2021] [Accepted: 02/18/2022] [Indexed: 12/30/2022] Open
Abstract
Individuals with autism spectrum disorder (ASD) exhibit an increased burden of de novo mutations (DNMs) in a broadening range of genes. While these studies have implicated hundreds of genes in ASD pathogenesis, which DNMs cause functional consequences in vivo remains unclear. We functionally test the effects of ASD missense DNMs using Drosophila through "humanization" rescue and overexpression-based strategies. We examine 79 ASD variants in 74 genes identified in the Simons Simplex Collection and find 38% of them to cause functional alterations. Moreover, we identify GLRA2 as the cause of a spectrum of neurodevelopmental phenotypes beyond ASD in 13 previously undiagnosed subjects. Functional characterization of variants in ASD candidate genes points to conserved neurobiological mechanisms and facilitates gene discovery for rare neurodevelopmental diseases.
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Affiliation(s)
- Paul C Marcogliese
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital (TCH), Houston, TX 77030, USA
| | - Samantha L Deal
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital (TCH), Houston, TX 77030, USA; Program in Developmental Biology, BCM, Houston, TX 77030, USA
| | - Jonathan Andrews
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital (TCH), Houston, TX 77030, USA
| | - J Michael Harnish
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital (TCH), Houston, TX 77030, USA
| | - V Hemanjani Bhavana
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital (TCH), Houston, TX 77030, USA
| | - Hillary K Graves
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital (TCH), Houston, TX 77030, USA
| | - Sharayu Jangam
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital (TCH), Houston, TX 77030, USA
| | - Xi Luo
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital (TCH), Houston, TX 77030, USA; Department of Pediatrics, Division of Hematology/Oncology, BCM, Houston, TX 77030, USA
| | - Ning Liu
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital (TCH), Houston, TX 77030, USA; Baylor Genetics Laboratories, Houston, TX 77021, USA
| | - Danqing Bei
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital (TCH), Houston, TX 77030, USA
| | - Yu-Hsin Chao
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital (TCH), Houston, TX 77030, USA
| | - Brooke Hull
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital (TCH), Houston, TX 77030, USA
| | - Pei-Tseng Lee
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital (TCH), Houston, TX 77030, USA
| | - Hongling Pan
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital (TCH), Houston, TX 77030, USA
| | - Pradnya Bhadane
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital (TCH), Houston, TX 77030, USA
| | - Mei-Chu Huang
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital (TCH), Houston, TX 77030, USA
| | - Colleen M Longley
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital (TCH), Houston, TX 77030, USA; Program in Developmental Biology, BCM, Houston, TX 77030, USA
| | - Hsiao-Tuan Chao
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital (TCH), Houston, TX 77030, USA; Department of Pediatrics, Division of Neurology and Developmental Neuroscience, BCM, Houston, TX 77030, USA; Department of Neuroscience, BCM, Houston, TX 77030, USA; McNair Medical Institute, The Robert and Janice McNair Foundation, Houston, TX 77030, USA; TCH, Houston, TX 77030, USA; Development, Disease Models & Therapeutics Graduate Program, BCM, Houston, TX 77030, USA
| | - Hyung-Lok Chung
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital (TCH), Houston, TX 77030, USA; Howard Hughes Medical Institute, Houston, TX 77030, USA
| | - Nele A Haelterman
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital (TCH), Houston, TX 77030, USA
| | - Oguz Kanca
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital (TCH), Houston, TX 77030, USA
| | - Sathiya N Manivannan
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital (TCH), Houston, TX 77030, USA
| | - Linda Z Rossetti
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA
| | - Ryan J German
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital (TCH), Houston, TX 77030, USA
| | - Amanda Gerard
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; TCH, Houston, TX 77030, USA
| | | | - Sarah Fehr
- Praxis für Humangenetik Tübingen, Tübingen, Germany
| | - Renzo Guerrini
- Neuroscience Department, Children's Hospital Meyer-University of Florence, Florence, Italy
| | - Annalisa Vetro
- Neuroscience Department, Children's Hospital Meyer-University of Florence, Florence, Italy
| | - Eleina England
- The Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Chaya N Murali
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; TCH, Houston, TX 77030, USA
| | - Tahsin Stefan Barakat
- Department of Clinical Genetics, Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Marieke F van Dooren
- Department of Clinical Genetics, Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Martina Wilke
- Department of Clinical Genetics, Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Marjon van Slegtenhorst
- Department of Clinical Genetics, Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Gaetan Lesca
- Department of Medical Genetics, Lyon University Hospital, Université Claude Bernard Lyon 1, Lyon, France; Institut NeuroMyoGène, CNRS UMR 5310 - INSERM U1217, Université Claude Bernard Lyon 1, Lyon, France
| | - Isabelle Sabatier
- Department of Pediatric Neurology, Lyon University Hospitals, Lyon, France
| | - Nicolas Chatron
- Department of Medical Genetics, Lyon University Hospital, Université Claude Bernard Lyon 1, Lyon, France; Institut NeuroMyoGène, CNRS UMR 5310 - INSERM U1217, Université Claude Bernard Lyon 1, Lyon, France
| | - Catherine A Brownstein
- Division of Genetics and Genomics, Boston Children's Hospital, Boston, MA 02115, USA; The Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Jill A Madden
- Division of Genetics and Genomics, Boston Children's Hospital, Boston, MA 02115, USA; The Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, MA 02115, USA
| | - Pankaj B Agrawal
- Division of Genetics and Genomics, Boston Children's Hospital, Boston, MA 02115, USA; The Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA; Division of Newborn Medicine, Boston Children's Hospital, Boston, MA 02115, USA
| | - Boris Keren
- Genetic Department, Pitié-Salpêtrière Hospital, APHP.Sorbonne Université, Paris 75013, France
| | - Thomas Courtin
- Genetic Department, Pitié-Salpêtrière Hospital, APHP.Sorbonne Université, Paris 75013, France
| | - Laurence Perrin
- Genetic Department, Robert Debré Hospital, APHP.Nord-Université de Paris, Paris 75019, France
| | - Melanie Brugger
- Institute of Human Genetics, Technical University Munich, Munich, Germany
| | - Timo Roser
- Division of Pediatric Neurology, Developmental Medicine and Social Pediatrics, Department of Pediatrics, Dr. von Hauner Children's Hospital, Ludwig-Maximilians-University, Lindwurmstraße 4, 80337 Munich, Germany
| | - Steffen Leiz
- Department of Pediatrics and Adolescent Medicine, Hospital Dritter Orden, Munich, Germany
| | - Frederic Tran Mau-Them
- INSERM U1231, LNC UMR1231 GAD, Burgundy University, 21000 Dijon, France; Laboratoire de Génétique, Innovation en Diagnostic Génomique des Maladies Rares UF6254, Plateau Technique de Biologie, CHU Dijon, 14 Rue Paul Gaffarel, BP 77908, 21079 Dijon, France
| | - Julian Delanne
- INSERM U1231, LNC UMR1231 GAD, Burgundy University, 21000 Dijon, France
| | - Elena Sukarova-Angelovska
- Department of Endocrinology and Genetics, University Clinic for Children's Diseases, Medical Faculty, University Sv. Kiril i Metodij, Skopje, Republic of Macedonia
| | - Slavica Trajkova
- Department of Medical Sciences, University of Torino, Turin, Italy
| | - Erik Rosenhahn
- Institute of Human Genetics, University of Leipzig Medical Center, Leipzig, Germany
| | - Vincent Strehlow
- Institute of Human Genetics, University of Leipzig Medical Center, Leipzig, Germany
| | - Konrad Platzer
- Institute of Human Genetics, University of Leipzig Medical Center, Leipzig, Germany
| | - Roberto Keller
- Adult Autism Center, Mental Health Department, Health Unit ASL Città di Torino, Turin, Italy
| | - Lisa Pavinato
- Department of Medical Sciences, University of Torino, Turin, Italy; Institute of Human Genetics and Center for Molecular Medicine Cologne, University of Cologne, Cologne, Germany
| | - Alfredo Brusco
- Department of Medical Sciences, University of Torino, Turin, Italy; Medical Genetics Unit, Città della Salute e della Scienza, University Hospital, Turin, Italy
| | - Jill A Rosenfeld
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; Baylor Genetics Laboratories, Houston, TX 77021, USA
| | - Ronit Marom
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; TCH, Houston, TX 77030, USA
| | - Michael F Wangler
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital (TCH), Houston, TX 77030, USA; TCH, Houston, TX 77030, USA; Development, Disease Models & Therapeutics Graduate Program, BCM, Houston, TX 77030, USA.
| | - Shinya Yamamoto
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital (TCH), Houston, TX 77030, USA; Program in Developmental Biology, BCM, Houston, TX 77030, USA; Department of Neuroscience, BCM, Houston, TX 77030, USA; Development, Disease Models & Therapeutics Graduate Program, BCM, Houston, TX 77030, USA.
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Futagbi G, Otu PS, Abdul-Rahman M, Aidoo EK, Lo AC, Gyan BA, Afrane YA, Amoah LE. Association of TNF-Alpha, MBL2, NOS2, and G6PD with Malaria Outcomes in People in Southern Ghana. Genet Res (Camb) 2022; 2022:6686406. [PMID: 35291755 PMCID: PMC8901335 DOI: 10.1155/2022/6686406] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 01/11/2022] [Accepted: 02/10/2022] [Indexed: 11/17/2022] Open
Abstract
Background One major issue that has set back the gains of the numerous malaria control interventions that national malaria control programs have implemented is asymptomatic malaria. Certain host genetic factors are known to influence symptomatic malaria; however, not much is known about how host genetics influences the acquisition of asymptomatic malaria. Methods Genomic DNA was extracted from whole blood collected from 60 symptomatic and 149 nonfebrile (asymptomatic, N = 109, and uninfected, N = 40) volunteers aged between 2 and 69 years from a high (Obom) and a low (Asutsuare) malaria transmission setting in Southern Ghana. Restriction fragment length polymorphism (RFLP) was used to determine polymorphisms at the MBL2 54, TNF-α 308, NOS2 954, and G6PD 202/376 gene loci. Results Polymorphisms at the MBL2 54 and TNF-α 308 loci were significantly different amongst the three categories of volunteers in both Asutsuare (p = 0.006) and Obom (p=0.05). In Asutsuare, a low malaria transmission area, the allele G has significantly higher odds (3.15) of supporting asymptomatic malaria as against symptomatic malaria. There were significantly higher odds of TNF-α genotype GA being associated with symptomatic malaria as against asymptomatic malaria in both sites, Obom (p=0.027) and Asutsuare (p=0.027). The allele B of the G6PD gene was more prevalent in symptomatic rather than asymptomatic parasite-infected individuals in both Obom (p=0.001) and Asutsuare (p=0.003). Conclusion Individuals in Southern Ghana carrying the TNF-α 308 GA genotype are more likely to exhibit symptoms of malaria when infected with the malaria parasite as opposed to harboring an asymptomatic infection. Also, the B allele of the G6PD gene is likely to prevent a P. falciparum-infected person from exhibiting symptoms and thereby promote asymptomatic parasite carriage.
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Affiliation(s)
- Godfred Futagbi
- Department of Animal Biology and Conservation Science, College of Basic and Applied Sciences, University of Ghana, Accra, Ghana
| | - Paulina S Otu
- Department of Medical Microbiology, University of Ghana Medical School, University of Ghana, Accra, Ghana
| | - Mubarak Abdul-Rahman
- Department of Pathology, University of Ghana Medical School, University of Ghana, Accra, Ghana
| | - Ebenezer K Aidoo
- Department of Medical Laboratory, Accra Technical University, Accra, Ghana
| | - Aminata C Lo
- Immunology Department, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
- Department of Medical Parasitology, Faculty of Medicine, University Cheikh Anta Diop, Dakar, Senegal
| | - Ben A Gyan
- Immunology Department, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | - Yaw A Afrane
- Department of Medical Microbiology, University of Ghana Medical School, University of Ghana, Accra, Ghana
| | - Linda E Amoah
- Immunology Department, Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
- West Africa Center for Cell Biology of Infectious Pathogens, University of Ghana, Accra, Ghana
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7
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Kawatake-Kuno A, Murai T, Uchida S. The Molecular Basis of Depression: Implications of Sex-Related Differences in Epigenetic Regulation. Front Mol Neurosci 2021; 14:708004. [PMID: 34276306 PMCID: PMC8282210 DOI: 10.3389/fnmol.2021.708004] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 06/14/2021] [Indexed: 12/22/2022] Open
Abstract
Major depressive disorder (MDD) is a leading cause of disability worldwide. Although the etiology and pathophysiology of MDD remain poorly understood, aberrant neuroplasticity mediated by the epigenetic dysregulation of gene expression within the brain, which may occur due to genetic and environmental factors, may increase the risk of this disorder. Evidence has also been reported for sex-related differences in the pathophysiology of MDD, with female patients showing a greater severity of symptoms, higher degree of functional impairment, and more atypical depressive symptoms. Males and females also differ in their responsiveness to antidepressants. These clinical findings suggest that sex-dependent molecular and neural mechanisms may underlie the development of depression and the actions of antidepressant medications. This review discusses recent advances regarding the role of epigenetics in stress and depression. The first section presents a brief introduction of the basic mechanisms of epigenetic regulation, including histone modifications, DNA methylation, and non-coding RNAs. The second section reviews their contributions to neural plasticity, the risk of depression, and resilience against depression, with a particular focus on epigenetic modulators that have causal relationships with stress and depression in both clinical and animal studies. The third section highlights studies exploring sex-dependent epigenetic alterations associated with susceptibility to stress and depression. Finally, we discuss future directions to understand the etiology and pathophysiology of MDD, which would contribute to optimized and personalized therapy.
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Affiliation(s)
- Ayako Kawatake-Kuno
- SK Project, Medical Innovation Center, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Toshiya Murai
- SK Project, Medical Innovation Center, Kyoto University Graduate School of Medicine, Kyoto, Japan.,Department of Psychiatry, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Shusaku Uchida
- SK Project, Medical Innovation Center, Kyoto University Graduate School of Medicine, Kyoto, Japan
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8
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Agrawal H, Das N, Nathani S, Saha S, Saini S, Kakar SS, Roy P. An Assessment on Impact of COVID-19 Infection in a Gender Specific Manner. Stem Cell Rev Rep 2020; 17:94-112. [PMID: 33029768 PMCID: PMC7541100 DOI: 10.1007/s12015-020-10048-z] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/25/2020] [Indexed: 12/19/2022]
Abstract
Coronavirus disease 2019 (COVID-19) is caused by novel coronavirus Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It was first time reported in December 2019 in Wuhan, China and thereafter quickly spread across the globe. Till September 19, 2020, COVID-19 has spread to 216 countries and territories. Severe infection of SARS-CoV-2 cause extreme increase in inflammatory chemokines and cytokines that may lead to multi-organ damage and respiratory failure. Currently, no specific treatment and authorized vaccines are available for its treatment. Renin angiotensin system holds a promising role in human physiological system specifically in regulation of blood pressure and electrolyte and fluid balance. SARS-CoV-2 interacts with Renin angiotensin system by utilizing angiotensin-converting enzyme 2 (ACE2) as a receptor for its cellular entry. This interaction hampers the protective action of ACE2 in the cells and causes injuries to organs due to persistent angiotensin II (Ang-II) level. Patients with certain comorbidities like hypertension, diabetes, and cardiovascular disease are under the high risk of COVID-19 infection and mortality. Moreover, evidence obtained from several reports also suggests higher susceptibility of male patients for COVID-19 mortality and other acute viral infections compared to females. Analysis of severe acute respiratory syndrome coronavirus (SARS) and Middle East respiratory syndrome coronavirus (MERS) epidemiological data also indicate a gender-based preference in disease consequences. The current review addresses the possible mechanisms responsible for higher COVID-19 mortality among male patients. The major underlying aspects that was looked into includes smoking, genetic factors, and the impact of reproductive hormones on immune systems and inflammatory responses. Detailed investigations of this gender disparity could provide insight into the development of patient tailored therapeutic approach which would be helpful in improving the poor outcomes of COVID-19. Graphical abstract.
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Affiliation(s)
- Himanshu Agrawal
- Molecular Endocrinology Laboratory, Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, 247667, India
| | - Neeladrisingha Das
- Molecular Endocrinology Laboratory, Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, 247667, India
| | - Sandip Nathani
- Molecular Endocrinology Laboratory, Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, 247667, India
| | - Sarama Saha
- Department of Biochemistry, All India Institute of Medical Sciences, Rishikesh, India
| | - Surendra Saini
- Molecular Endocrinology Laboratory, Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, 247667, India
| | - Sham S Kakar
- Department of Physiology, James Graham Brown Cancer Center, University of Louisville, Louisville, KY, 40292, USA
| | - Partha Roy
- Molecular Endocrinology Laboratory, Department of Biotechnology, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, 247667, India.
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9
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Salama EA, Adbeltawab RE, El Tayebi HM. XIST and TSIX: Novel Cancer Immune Biomarkers in PD-L1-Overexpressing Breast Cancer Patients. Front Oncol 2020; 9:1459. [PMID: 31998636 PMCID: PMC6966712 DOI: 10.3389/fonc.2019.01459] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Accepted: 12/05/2019] [Indexed: 12/20/2022] Open
Abstract
Escaping antitumor immunity is a hallmark in cancer progression. Programmed cell death protein 1 (PD-1) is an immune checkpoint receptor responsible for the maintenance of immune tolerance; PD-1 ligand (PD-L1) is overexpressed in tumor cells, simplifying their escape from the immune system through T-cell function suppression. Notwithstanding that cancer antigen (CA)125, carcinoembryonic antigen (CEA), CA15-3, and alpha-fetoprotein (AFP) are among conventional breast cancer diagnostic biomarkers, their lack of sensitivity and specificity resides among their major limitations. Furthermore, human epidermal growth factor receptor (HER)2 and interleukin (IL)-6-demonstrated as breast cancer immune biomarkers-still possess limitations, for instance, technical detection problems and stability problems, which necessitate the discovery of novel, stable non-invasive cancer immune biomarkers. XIST and TSIX are two long non-coding (lnc)RNAs possessing a role in X chromosome inactivation (XCI) as well as in breast cancer (BC). In the present study, they were investigated as stable non-invasive breast cancer immune biomarkers. The study demonstrated that PD-L1 was overexpressed in the different molecular subtypes of breast cancer patients as well as in MDA-MB-231 cells. Furthermore, lncRNAs XIST and TSIX were markedly increased in the tissues, lymph nodes, and different body fluids of breast cancer patients compared to controls. In addition, XIST and TSIX were differentially expressed in subtypes of BC patients, and their levels were correlated to PD-L1 expression level. In conclusion, this correlative study has shed light on the role of both lncRNAs XIST and TSIX as potential non-invasive BC immune biomarkers reflecting the evaded immune system of the patient and overcoming the instability problem of common BC biomarkers.
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Affiliation(s)
- Esraa A. Salama
- Molecular Pharmacology Research Group, Department of Pharmacology and Toxicology, Faculty of Pharmacy and Biotechnology, German University in Cairo, Cairo, Egypt
| | - Reda E. Adbeltawab
- Department of Surgery, Faculty of Medicine, Ain Shams University, Cairo, Egypt
| | - Hend M. El Tayebi
- Molecular Pharmacology Research Group, Department of Pharmacology and Toxicology, Faculty of Pharmacy and Biotechnology, German University in Cairo, Cairo, Egypt
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10
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El Ayachi I, Zou XY, Yan X, Lou Y, Huang GTJ. Expression of Normal or Mutated X-Linked BCOR Transcripts in OFCD iPSCs. J Dent Res 2019; 99:196-203. [PMID: 31775564 DOI: 10.1177/0022034519890323] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Reprogramming diseased cells with mutated genes into induced pluripotent stem cells (iPSCs) can allow studies of disease mechanism and correct the mutation. Oculofaciocardiodental (OFCD) syndrome is a developmental disorder caused by heterozygous mutations in the X-linked BCL-6 corepressor (BCOR) gene. In this present study, we aimed to reprogram stem cells from a tooth apical papilla (SCAP) of a patient with OFCD, termed SCAP-O, into iPSCs. The SCAP-O carry a copy of the BCOR gene having 1 nucleotide deletion in 1 of the alleles, therefore harboring a mixture of cells expressing either normal (SCAP-OBCOR-WT) or mutated (SCAP-OBCOR-mut) BCOR transcripts. We subcloned SCAP-O and separated SCAP-OBCOR-WT and SCAP-OBCOR-mut as verified by sequencing. The selected subclone SCAP-OBCOR-mut expressed only the mutated BCOR transcripts and remained in such condition after multiple passages. We reprogrammed SCAP-O and subclone SCAP-OBCOR-mut into transgene-free iPSCs using an excisable lentiviral vector system (hSTEMCCA-loxP) carrying 4 reprogramming factors in a single cassette, followed by removal of transgenes via Cre-mediated excision. We found that after reprogramming SCAP-O or subclone SCAP-OBCOR-mut into iPSCs, some of the iPSC clones expressed either solely the normal BCOR-WT or BCOR-mut transcripts, while other clones expressed both BCOR-WT and BCOR-mut transcripts. This is our first step toward establishing OFCD study models by generating isogenic control BCOR-WT iPSCs versus BCOR-mut iPSCs.
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Affiliation(s)
- I El Ayachi
- Department of Bioscience Research, College of Dentistry, University of Tennessee Health Science Center, Memphis, TN, USA
| | - X-Y Zou
- Department of Cariology, Endodontology and Operative Dentistry, School and Hospital of Stomatology, Peking University, Beijing, China.,Department of Endodontics, Henry M. Goldman School of Dental Medicine, Boston University, Boston, MA, USA
| | - X Yan
- Department of Endodontics, Henry M. Goldman School of Dental Medicine, Boston University, Boston, MA, USA
| | - Y Lou
- Department of Bioscience Research, College of Dentistry, University of Tennessee Health Science Center, Memphis, TN, USA.,Department of Endodontics, Henry M. Goldman School of Dental Medicine, Boston University, Boston, MA, USA
| | - G T-J Huang
- Department of Bioscience Research, College of Dentistry, University of Tennessee Health Science Center, Memphis, TN, USA.,Department of Endodontics, Henry M. Goldman School of Dental Medicine, Boston University, Boston, MA, USA
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11
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Glandular defects in the mouse uterus with sustained activation of TGF-beta signaling is associated with altered differentiation of endometrial stromal cells and formation of stromal compartment. PLoS One 2018; 13:e0209417. [PMID: 30550590 PMCID: PMC6294433 DOI: 10.1371/journal.pone.0209417] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 12/05/2018] [Indexed: 11/24/2022] Open
Abstract
Uterine gland development, also known as adenogenesis, is a key uterine morphogenic process indispensable for normal uterine function and fertility. Our earlier studies have reported that overactivation of TGFB receptor 1 (TGFBR1) in the mouse uterus using progesterone receptor (Pgr)-Cre recombinase causes female infertility, defective decidualization, and reduced uterine gland formation, a developmental milestone of postnatal uterus. To understand mechanisms that underpin the disrupted uterine gland formation in mice with sustained activation of TGFBR1, we raised the question of whether early postnatal adenogenesis was compromised in these mice. Experiments were designed using mice with constitutive activation of TGFBR1 driven by Pgr-Cre to determine the timing of adenogenic defects and potential mechanisms associated with dysregulation of adenogenic genes, luminal epithelial cell proliferation and endometrial fibrotic changes. Uterine tissues from mice with constitutive activation of TGFBR1 were collected during the critical time window of adenogenesis and analyzed together with age-matched controls. Multiple approaches including immunohistochemistry, immunofluorescence, Trichrome staining, quantitative real-time PCR, western blot, conditional knockout and human endometrial cell culture were utilized. TGFBR1 activation in the mouse uterus suppressed adenogenesis during postnatal uterine development, concomitant with the aberrant differentiation of uterine stromal cells. Analysis of transcript expression of WNT pathway components revealed dysregulation of adenogenesis-associated genes. Notably, the adenogenic defects occurred in spite of the increased proliferation of uterine luminal epithelial cells, accompanied by increased expression of genes associated with fibrotic changes. Moreover, the adenogenic defects were alleviated in mice where TGFBR1 was activated in presumably half of the complement of uterine cells. Our results suggest that altered differentiation of endometrial stromal cells and formation of stromal compartment promote adenogenic defects.
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12
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Carmona S, Lin B, Chou T, Arroyo K, Sun S. LncRNA Jpx induces Xist expression in mice using both trans and cis mechanisms. PLoS Genet 2018; 14:e1007378. [PMID: 29734339 PMCID: PMC5957434 DOI: 10.1371/journal.pgen.1007378] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Revised: 05/17/2018] [Accepted: 04/24/2018] [Indexed: 11/30/2022] Open
Abstract
Mammalian X chromosome dosage compensation balances X-linked gene products between sexes and is coordinated by the long noncoding RNA (lncRNA) Xist. Multiple cis and trans-acting factors modulate Xist expression; however, the primary competence factor responsible for activating Xist remains a subject of dispute. The lncRNA Jpx is a proposed competence factor, yet it remains unknown if Jpx is sufficient to activate Xist expression in mice. Here, we utilize a novel transgenic mouse system to demonstrate a dose-dependent relationship between Jpx copy number and ensuing Jpx and Xist expression. By localizing transcripts of Jpx and Xist using RNA Fluorescence in situ Hybridization (FISH) in mouse embryonic cells, we provide evidence of Jpx acting in both trans and cis to activate Xist. Our data contribute functional and mechanistic insight for lncRNA activity in mice, and argue that Jpx is a competence factor for Xist activation in vivo. Long noncoding RNA (lncRNA) have been identified in all eukaryotes but mechanisms of lncRNA function remain challenging to study in vivo. A classic model of lncRNA function and mechanism is X-Chromosome Inactivation (XCI): an essential process which balances X-linked gene expression between male and female mammals. The “master regulator” of XCI is lncRNA Xist, which is responsible for silencing one of the two X chromosomes in females. Another lncRNA, Jpx, has been proposed to activate Xist gene expression in mouse embryonic stem cells; however, no mouse models exist to address Jpx function in vivo. In this study, we developed a novel transgenic mouse system to demonstrate the regulatory mechanisms of lncRNA Jpx. We observed a dose-dependent relationship between Jpx copy number and Xist expression in transgenic mice, suggesting that Jpx is sufficient to activate Xist expression in vivo. In addition, we analyzed Jpx’s allelic origin and have provided evidence for Jpx inducing Xist transcription using both trans and cis mechanisms. Our work provides a framework for lncRNA functional studies in mice, which will help us understand how lncRNA regulate eukaryotic gene expression.
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Affiliation(s)
- Sarah Carmona
- Department of Developmental and Cell Biology, Ayala School of Biological Sciences, University of California, Irvine, Irvine, CA, United States of America
| | - Benjamin Lin
- Department of Developmental and Cell Biology, Ayala School of Biological Sciences, University of California, Irvine, Irvine, CA, United States of America
| | - Tristan Chou
- Department of Developmental and Cell Biology, Ayala School of Biological Sciences, University of California, Irvine, Irvine, CA, United States of America
| | - Katti Arroyo
- Department of Developmental and Cell Biology, Ayala School of Biological Sciences, University of California, Irvine, Irvine, CA, United States of America
| | - Sha Sun
- Department of Developmental and Cell Biology, Ayala School of Biological Sciences, University of California, Irvine, Irvine, CA, United States of America
- * E-mail:
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13
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De Paepe B, Lefever S, Mestdagh P. How long noncoding RNAs enforce their will on mitochondrial activity: regulation of mitochondrial respiration, reactive oxygen species production, apoptosis, and metabolic reprogramming in cancer. Curr Genet 2017; 64:163-172. [PMID: 28879612 DOI: 10.1007/s00294-017-0744-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 08/17/2017] [Accepted: 08/31/2017] [Indexed: 12/13/2022]
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14
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Atlasi Y, Stunnenberg HG. The interplay of epigenetic marks during stem cell differentiation and development. Nat Rev Genet 2017; 18:643-658. [PMID: 28804139 DOI: 10.1038/nrg.2017.57] [Citation(s) in RCA: 336] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Chromatin, the template for epigenetic regulation, is a highly dynamic entity that is constantly reshaped during early development and differentiation. Epigenetic modification of chromatin provides the necessary plasticity for cells to respond to environmental and positional cues, and enables the maintenance of acquired information without changing the DNA sequence. The mechanisms involve, among others, chemical modifications of chromatin, changes in chromatin constituents and reconfiguration of chromatin interactions and 3D structure. New advances in genome-wide technologies have paved the way towards an integrative view of epigenome dynamics during cell state transitions, and recent findings in embryonic stem cells highlight how the interplay between different epigenetic layers reshapes the transcriptional landscape.
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Affiliation(s)
- Yaser Atlasi
- Department of Molecular Biology, Faculty of Science, Radboud University, 6525 GA Nijmegen, The Netherlands
| | - Hendrik G Stunnenberg
- Department of Molecular Biology, Faculty of Science, Radboud University, 6525 GA Nijmegen, The Netherlands
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15
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Frattini S, Capra E, Lazzari B, McKay SD, Coizet B, Talenti A, Groppetti D, Riccaboni P, Pecile A, Chessa S, Castiglioni B, Williams JL, Pagnacco G, Stella A, Crepaldi P. Genome-wide analysis of DNA methylation in hypothalamus and ovary of Capra hircus. BMC Genomics 2017. [PMID: 28645321 PMCID: PMC5481934 DOI: 10.1186/s12864-017-3866-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND DNA methylation is a frequently studied epigenetic modification due to its role in regulating gene expression and hence in biological processes and in determining phenotypic plasticity in organisms. Rudimentary DNA methylation patterns for some livestock species are publically available: among these, goat methylome deserves to be further explored. RESULTS Genome-wide DNA methylation maps of the hypothalamus and ovary from Saanen goats were generated using Methyl-CpG binding domain protein sequencing (MBD-seq). Analysis of DNA methylation patterns indicate that the majority of methylation peaks found within genes are located gene body regions, for both organs. Analysis of the distribution of methylated sites per chromosome showed that chromosome X had the lowest number of methylation peaks. The X chromosome has one of the highest percentages of methylated CpG islands in both organs, and approximately 50% of the CpG islands in the goat epigenome are methylated in hypothalamus and ovary. Organ-specific Differentially Methylated Genes (DMGs) were correlated with the expression levels. CONCLUSIONS The comparison between transcriptome and methylome in hypothalamus and ovary showed that a higher level of methylation is not accompanied by a higher gene suppression. The genome-wide DNA methylation map for two goat organs produced here is a valuable starting point for studying the involvement of epigenetic modifications in regulating goat reproduction performance.
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Affiliation(s)
- Stefano Frattini
- Department of Veterinary Science, University of Milan, Milan, Italy
| | - Emanuele Capra
- Institute of Agricultural Biology and Biotechnology, National Research Council UOS of Lodi, Lodi, Italy
| | - Barbara Lazzari
- Institute of Agricultural Biology and Biotechnology, National Research Council UOS of Lodi, Lodi, Italy.,PTP Science Park, Lodi, Italy
| | - Stephanie D McKay
- Department of Animal & Veterinary Sciences, University of Vermont, Burlington, VT, USA
| | - Beatrice Coizet
- Department of Veterinary Science, University of Milan, Milan, Italy
| | - Andrea Talenti
- Department of Veterinary Science, University of Milan, Milan, Italy
| | - Debora Groppetti
- Department of Veterinary Science, University of Milan, Milan, Italy
| | - Pietro Riccaboni
- Department of Veterinary Science, University of Milan, Milan, Italy
| | | | - Stefania Chessa
- Institute of Agricultural Biology and Biotechnology, National Research Council UOS of Lodi, Lodi, Italy
| | - Bianca Castiglioni
- Institute of Agricultural Biology and Biotechnology, National Research Council UOS of Lodi, Lodi, Italy
| | - John L Williams
- The Davies Research Centre, School of Animal and Veterinary Sciences, University of Adelaide, Roseworthy, 5371, Australia
| | - Giulio Pagnacco
- Department of Veterinary Science, University of Milan, Milan, Italy
| | - Alessandra Stella
- Institute of Agricultural Biology and Biotechnology, National Research Council UOS of Lodi, Lodi, Italy.,PTP Science Park, Lodi, Italy
| | - Paola Crepaldi
- Department of Veterinary Science, University of Milan, Milan, Italy.
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16
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Postlmayr A, Wutz A. Insights into the Establishment of Chromatin States in Pluripotent Cells from Studies of X Inactivation. J Mol Biol 2017; 429:1521-1531. [PMID: 28315662 DOI: 10.1016/j.jmb.2017.03.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 03/07/2017] [Accepted: 03/10/2017] [Indexed: 11/20/2022]
Abstract
Animal development entails the sequential and coordinated specialization of cells. During cell differentiation, transcription factors, cell signaling pathways, and chromatin-associated protein complexes cooperate in regulating the expression of a large number of genes. Here, we review the present understanding of the establishment of chromatin states by focusing on X chromosome inactivation (XCI) as a model for facultative heterochromatin formation in female embryonic cells. The inactive X chromosome is large enough to be investigated by biochemical and microscopy techniques. In addition, the ability to compare the inactivated chromatin to the active X in male cells enables us to differentiate events specific to gene silencing during XCI from gene regulatory effects from changing pathways in the same cell. Findings in XCI are useful as blueprints for investigation of the action of epigenetic pathways in differentiation and lineage commitment. We summarize recent studies that have identified factors that are critical for chromosome-wide gene repression in XCI, and we discuss their implications for epigenetic regulation in pluripotent cells of the early embryo.
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Affiliation(s)
- Andreas Postlmayr
- Institute of Molecular Health Sciences, Swiss Federal Institute of Technology Zurich, Otto-Stern-Weg 7, 8093 Zurich, Switzerland; Life Science Zurich Graduate School, Molecular Life Sciences Program, University of Zurich, 8049 Zurich, Switzerland
| | - Anton Wutz
- Institute of Molecular Health Sciences, Swiss Federal Institute of Technology Zurich, Otto-Stern-Weg 7, 8093 Zurich, Switzerland.
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17
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Lau AC, Zhu KP, Brouhard EA, Davis MB, Csankovszki G. An H4K16 histone acetyltransferase mediates decondensation of the X chromosome in C. elegans males. Epigenetics Chromatin 2016; 9:44. [PMID: 27777629 PMCID: PMC5070013 DOI: 10.1186/s13072-016-0097-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 10/05/2016] [Indexed: 02/08/2023] Open
Abstract
Background In C. elegans, in order to equalize gene expression between the sexes and balance X and autosomal expression, two steps are believed to be required. First, an unknown mechanism is hypothesized to upregulate the X chromosome in both sexes. This mechanism balances the X to autosomal expression in males, but creates X overexpression in hermaphrodites. Therefore, to restore the balance, hermaphrodites downregulate gene expression twofold on both X chromosomes. While many studies have focused on X chromosome downregulation, the mechanism of X upregulation is not known. Results To gain more insight into X upregulation, we studied the effects of chromatin condensation and histone acetylation on gene expression levels in male C. elegans. We have found that the H4K16 histone acetyltransferase MYS-1/Tip60 mediates dramatic decondensation of the male X chromosome as measured by FISH. However, RNA-seq analysis revealed that MYS-1 contributes only slightly to upregulation of gene expression on the X chromosome. These results suggest that the level of chromosome decondensation does not necessarily correlate with the degree of gene expression change in vivo. Furthermore, the X chromosome is more sensitive to MYS-1-mediated decondensation than the autosomes, despite similar levels of H4K16ac on all chromosomes, as measured by ChIP-seq. H4K16ac levels weakly correlate with gene expression levels on both the X and the autosomes, but highly expressed genes on the X chromosome do not contain exceptionally high levels of H4K16ac. Conclusion These results indicate that H4K16ac and chromosome decondensation influence regulation of the male X chromosome; however, they do not fully account for the high levels of gene expression observed on the X chromosomes. Electronic supplementary material The online version of this article (doi:10.1186/s13072-016-0097-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Alyssa C Lau
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, 830 N. University Ave., Ann Arbor, MI 48109-1048 USA ; Genome Technologies, The Jackson Laboratory for Genomic Medicine, Farmington, CT 06032 USA
| | - Kevin P Zhu
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, 830 N. University Ave., Ann Arbor, MI 48109-1048 USA
| | - Elizabeth A Brouhard
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, 830 N. University Ave., Ann Arbor, MI 48109-1048 USA
| | - Michael B Davis
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, 830 N. University Ave., Ann Arbor, MI 48109-1048 USA
| | - Györgyi Csankovszki
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, 830 N. University Ave., Ann Arbor, MI 48109-1048 USA
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18
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Li C, Hong T, Webb CH, Karner H, Sun S, Nie Q. A self-enhanced transport mechanism through long noncoding RNAs for X chromosome inactivation. Sci Rep 2016; 6:31517. [PMID: 27527711 PMCID: PMC4985753 DOI: 10.1038/srep31517] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2016] [Accepted: 07/21/2016] [Indexed: 11/09/2022] Open
Abstract
X-chromosome inactivation (XCI) is the mammalian dosage compensation strategy for balancing sex chromosome content between females and males. While works exist on initiation of symmetric breaking, the underlying allelic choice mechanisms and dynamic regulation responsible for the asymmetric fate determination of XCI remain elusive. Here we combine mathematical modeling and experimental data to examine the mechanism of XCI fate decision by analyzing the signaling regulatory circuit associated with long noncoding RNAs (lncRNAs) involved in XCI. We describe three plausible gene network models that incorporate features of lncRNAs in their localized actions and rapid transcriptional turnovers. In particular, we show experimentally that Jpx (a lncRNA) is transcribed biallelically, escapes XCI, and is asymmetrically dispersed between two X's. Subjecting Jpx to our test of model predictions against previous experimental observations, we identify that a self-enhanced transport feedback mechanism is critical to XCI fate decision. In addition, the analysis indicates that an ultrasensitive response of Jpx signal on CTCF is important in this mechanism. Overall, our combined modeling and experimental data suggest that the self-enhanced transport regulation based on allele-specific nature of lncRNAs and their temporal dynamics provides a robust and novel mechanism for bi-directional fate decisions in critical developmental processes.
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Affiliation(s)
- Chunhe Li
- Department of Mathematics, University of California, Irvine, Irvine, CA 92697, USA
- Center for Complex Biological Systems, University of California, Irvine, Irvine, CA 92697, USA
| | - Tian Hong
- Department of Mathematics, University of California, Irvine, Irvine, CA 92697, USA
- Center for Complex Biological Systems, University of California, Irvine, Irvine, CA 92697, USA
| | - Chiu-Ho Webb
- Department of Developmental and Cell Biology, University of California, Irvine, Irvine, CA 92697, USA
| | - Heather Karner
- Department of Developmental and Cell Biology, University of California, Irvine, Irvine, CA 92697, USA
| | - Sha Sun
- Center for Complex Biological Systems, University of California, Irvine, Irvine, CA 92697, USA
- Department of Developmental and Cell Biology, University of California, Irvine, Irvine, CA 92697, USA
| | - Qing Nie
- Department of Mathematics, University of California, Irvine, Irvine, CA 92697, USA
- Center for Complex Biological Systems, University of California, Irvine, Irvine, CA 92697, USA
- Department of Developmental and Cell Biology, University of California, Irvine, Irvine, CA 92697, USA
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19
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Forde N, Maillo V, O'Gaora P, Simintiras CA, Sturmey RG, Ealy AD, Spencer TE, Gutierrez-Adan A, Rizos D, Lonergan P. Sexually Dimorphic Gene Expression in Bovine Conceptuses at the Initiation of Implantation. Biol Reprod 2016; 95:92. [PMID: 27488033 PMCID: PMC5333939 DOI: 10.1095/biolreprod.116.139857] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Accepted: 07/29/2016] [Indexed: 01/06/2023] Open
Abstract
In cattle, maternal recognition of pregnancy occurs on Day 16 via secretion of interferon tau (IFNT) by the conceptus. The endometrium can distinguish between embryos with different developmental competencies. In eutherian mammals, X-chromosome inactivation (XCI) is required to ensure an equal transcriptional level of most X-linked genes for both male and female embryos in adult tissues, but this process is markedly different in cattle than mice. We examined how sexual dimorphism affected conceptus transcript abundance and amino acid composition as well as the endometrial transcriptome during the peri-implantation period of pregnancy. Of the 5132 genes that were differentially expressed on Day 19 in male compared to female conceptuses, 2.7% were located on the X chromosome. Concentrations of specific amino acids were higher in the uterine luminal fluid of male compared to female conceptuses, while female conceptuses had higher transcript abundance of specific amino acid transporters (SLC6A19 and SLC1A35). Of note, the endometrial transcriptome was not different in cattle gestating a male or a female conceptus. These data support the hypothesis that, far from being a blastocyst-specific phenomenon, XCI is incomplete before and during implantation in cattle. Despite differences in transcript abundance and amino acid utilization in male versus female conceptuses, the sex of the conceptus itself does not elicit a different transcriptomic response in the endometrium.
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Affiliation(s)
- Niamh Forde
- School of Agriculture and Food Science, University College Dublin, Belfield, Dublin, Ireland
| | | | - Peadar O'Gaora
- School of Biomolecular and Biomedical Sciences, University College Dublin, Belfield, Dublin, Ireland
| | - Constantine A Simintiras
- Center for Cardiovascular and Metabolic Research, Hull York Medical School, University of Hull, Hull, United Kingdom
| | - Roger G Sturmey
- Center for Cardiovascular and Metabolic Research, Hull York Medical School, University of Hull, Hull, United Kingdom
| | - Alan D Ealy
- Department of Animal and Poultry Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia
| | - Thomas E Spencer
- Division of Animal Sciences, University of Missouri, Columbia, Missouri
| | | | | | - Patrick Lonergan
- School of Agriculture and Food Science, University College Dublin, Belfield, Dublin, Ireland
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20
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Amoah LE, Opong A, Ayanful-Torgby R, Abankwa J, Acquah FK. Prevalence of G6PD deficiency and Plasmodium falciparum parasites in asymptomatic school children living in southern Ghana. Malar J 2016; 15:388. [PMID: 27456336 PMCID: PMC4960760 DOI: 10.1186/s12936-016-1440-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 07/12/2016] [Indexed: 01/03/2023] Open
Abstract
Background Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-linked genetic disorder that results in impaired enzyme activity. Although G6PD deficiency is globally distributed it is more prevalent in malaria-endemic countries. Several mutations have been identified in the G6PD gene, which alter enzyme activity. The G6PD genotype predominantly found in sub-Saharan Africa is the G6PDB (G6PD376A) with (G6PD376G) and G6PDA- (G6PD376G/202A, G6PD376G/542T, G6PD376G/680T and G6PD376G/968C) occurring at lower frequencies. Aim The aim of this study was to identify the prevalence of G6PD deficiency and asymptomatic Plasmodium falciparum carriage in children living in southern Ghana and determine whether G6PD deficiency influences asymptomatic carriage of P. falciparum parasites. Methods Blood samples were obtained once a month from 170 healthy Ghanaian school children aged between 5 and 12 years from Basic schools in two communities Obom and Abura with similar rainfall patterns and malaria peak seasons. G6PD enzyme activity was assessed using the qualitative G6PD RDT kit (AccessBIO). G6PD genotyping and asymptomatic parasite carriage was determined by PCR followed by restriction fragment length polymorphism (RFLP) of DNA extracted from dried blood spots. Results The only sub-Saharan G6PD A- allele detected was the A376G/G202A found in 12.4 % (21/170), of the children and distributed as 4.1 % (7/170) A-, 1.8 % (3/170) A-/A- homozygous deficient males and females and 6.5 % (11/170) A/A- and B/A- heterozygous deficient females. Phenotypically, 10.6 % (15/142) of the children were G6PD deficient. The asymptomatic carriage of P. falciparum by PCR was 50, 29.4, 38.2 and 38.8 % over the months of February through May 2015, respectively, and 28.8, 22.4, 25.9 and 5.9 % by microscopy during the same periods. Conclusions G6PD deficiency was significantly associated with a lowered risk of PCR-estimated asymptomatic P. falciparum carriage in children during the off peak malaria season in Southern Ghana. Electronic supplementary material The online version of this article (doi:10.1186/s12936-016-1440-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Linda Eva Amoah
- Immunology Department, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Accra, Ghana.
| | - Akua Opong
- Immunology Department, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Accra, Ghana
| | - Ruth Ayanful-Torgby
- Immunology Department, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Accra, Ghana.,Ghana Health Service, Ministry of Health, Accra, Ghana
| | - Joana Abankwa
- Immunology Department, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Accra, Ghana
| | - Festus K Acquah
- Immunology Department, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Accra, Ghana
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21
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Prudhomme J, Morey C. Epigenesis and plasticity of mouse trophoblast stem cells. Cell Mol Life Sci 2016; 73:757-74. [PMID: 26542801 PMCID: PMC11108370 DOI: 10.1007/s00018-015-2086-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Accepted: 10/27/2015] [Indexed: 12/28/2022]
Abstract
The critical role of the placenta in supporting a healthy pregnancy is mostly ensured by the extraembryonic trophoblast lineage that acts as the interface between the maternal and the foetal compartments. The diverse trophoblast cell subtypes that form the placenta originate from a single layer of stem cells that emerge from the embryo when the earliest cell fate decisions are occurring. Recent studies show that these trophoblast stem cells exhibit extensive plasticity as they are capable of differentiating down multiple pathways and are easily converted into embryonic stem cells in vitro. In this review, we discuss current knowledge of the mechanisms and control of the epigenesis of mouse trophoblast stem cells through a comparison with the corresponding mechanisms in pluripotent embryonic stem cells. To illustrate some of the more striking manifestations of the epigenetic plasticity of mouse trophoblast stem cells, we discuss them within the context of two paradigms of epigenetic regulation of gene expression: the imprinted gene expression of specific loci and the process of X-chromosome inactivation.
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Affiliation(s)
- Julie Prudhomme
- Laboratoire de Génétique Moléculaire Murine, Institut Pasteur, 75015, Paris, France
| | - Céline Morey
- CNRS, UMR7216 Epigenetics and Cell Fate, 75013, Paris, France.
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22
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Marks H, Kerstens HHD, Barakat TS, Splinter E, Dirks RAM, van Mierlo G, Joshi O, Wang SY, Babak T, Albers CA, Kalkan T, Smith A, Jouneau A, de Laat W, Gribnau J, Stunnenberg HG. Dynamics of gene silencing during X inactivation using allele-specific RNA-seq. Genome Biol 2015; 16:149. [PMID: 26235224 PMCID: PMC4546214 DOI: 10.1186/s13059-015-0698-x] [Citation(s) in RCA: 97] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Accepted: 06/18/2015] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND During early embryonic development, one of the two X chromosomes in mammalian female cells is inactivated to compensate for a potential imbalance in transcript levels with male cells, which contain a single X chromosome. Here, we use mouse female embryonic stem cells (ESCs) with non-random X chromosome inactivation (XCI) and polymorphic X chromosomes to study the dynamics of gene silencing over the inactive X chromosome by high-resolution allele-specific RNA-seq. RESULTS Induction of XCI by differentiation of female ESCs shows that genes proximal to the X-inactivation center are silenced earlier than distal genes, while lowly expressed genes show faster XCI dynamics than highly expressed genes. The active X chromosome shows a minor but significant increase in gene activity during differentiation, resulting in complete dosage compensation in differentiated cell types. Genes escaping XCI show little or no silencing during early propagation of XCI. Allele-specific RNA-seq of neural progenitor cells generated from the female ESCs identifies three regions distal to the X-inactivation center that escape XCI. These regions, which stably escape during propagation and maintenance of XCI, coincide with topologically associating domains (TADs) as present in the female ESCs. Also, the previously characterized gene clusters escaping XCI in human fibroblasts correlate with TADs. CONCLUSIONS The gene silencing observed during XCI provides further insight in the establishment of the repressive complex formed by the inactive X chromosome. The association of escape regions with TADs, in mouse and human, suggests that TADs are the primary targets during propagation of XCI over the X chromosome.
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Affiliation(s)
- Hendrik Marks
- Radboud University, Faculty of Science, Department of Molecular Biology, Radboud Institute for Molecular Life Sciences (RIMLS), 6500HB, Nijmegen, The Netherlands.
| | - Hindrik H D Kerstens
- Radboud University, Faculty of Science, Department of Molecular Biology, Radboud Institute for Molecular Life Sciences (RIMLS), 6500HB, Nijmegen, The Netherlands.
| | - Tahsin Stefan Barakat
- Department of Reproduction and Development, Erasmus MC, University Medical Center, Rotterdam, The Netherlands.
| | - Erik Splinter
- Hubrecht Institute, University Medical Center Utrecht, Uppsalalaan 8, 3584CT, Utrecht, The Netherlands.
| | - René A M Dirks
- Radboud University, Faculty of Science, Department of Molecular Biology, Radboud Institute for Molecular Life Sciences (RIMLS), 6500HB, Nijmegen, The Netherlands.
| | - Guido van Mierlo
- Radboud University, Faculty of Science, Department of Molecular Biology, Radboud Institute for Molecular Life Sciences (RIMLS), 6500HB, Nijmegen, The Netherlands.
| | - Onkar Joshi
- Radboud University, Faculty of Science, Department of Molecular Biology, Radboud Institute for Molecular Life Sciences (RIMLS), 6500HB, Nijmegen, The Netherlands.
| | - Shuang-Yin Wang
- Radboud University, Faculty of Science, Department of Molecular Biology, Radboud Institute for Molecular Life Sciences (RIMLS), 6500HB, Nijmegen, The Netherlands.
| | - Tomas Babak
- Biology Department, Queen's University, Kingston, ON, Canada.
| | - Cornelis A Albers
- Radboud University, Faculty of Science, Department of Molecular Developmental Biology, Radboud Institute for Molecular Life Sciences (RIMLS), 6500HB, Nijmegen, The Netherlands.
| | - Tüzer Kalkan
- Wellcome Trust-Medical Research Council Stem Cell Institute, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QR, UK.
| | - Austin Smith
- Wellcome Trust-Medical Research Council Stem Cell Institute, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QR, UK.
| | - Alice Jouneau
- INRA, UMR1198 Biologie du Développement et Reproduction, F-78350, Jouy-en-Josas, France.
| | - Wouter de Laat
- Hubrecht Institute, University Medical Center Utrecht, Uppsalalaan 8, 3584CT, Utrecht, The Netherlands.
| | - Joost Gribnau
- Department of Reproduction and Development, Erasmus MC, University Medical Center, Rotterdam, The Netherlands.
| | - Hendrik G Stunnenberg
- Radboud University, Faculty of Science, Department of Molecular Biology, Radboud Institute for Molecular Life Sciences (RIMLS), 6500HB, Nijmegen, The Netherlands.
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23
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Gayen S, Maclary E, Buttigieg E, Hinten M, Kalantry S. A Primary Role for the Tsix lncRNA in Maintaining Random X-Chromosome Inactivation. Cell Rep 2015; 11:1251-65. [PMID: 25981039 DOI: 10.1016/j.celrep.2015.04.039] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 03/27/2015] [Accepted: 04/18/2015] [Indexed: 11/30/2022] Open
Abstract
Differentiating pluripotent epiblast cells in eutherians undergo random X-inactivation, which equalizes X-linked gene expression between the sexes by silencing one of the two X-chromosomes in females. Tsix RNA is believed to orchestrate the initiation of X-inactivation, influencing the choice of which X remains active by preventing expression of the antisense Xist RNA, which is required to silence the inactive-X. Here we profile X-chromosome activity in Tsix-mutant (X(ΔTsix)) mouse embryonic epiblasts, epiblast stem cells, and embryonic stem cells. Unexpectedly, we find that Xist is stably repressed on the X(ΔTsix) in both sexes in undifferentiated epiblast cells in vivo and in vitro, resulting in stochastic X-inactivation in females despite Tsix-heterozygosity. Tsix is instead required to silence Xist on the active-X as epiblast cells differentiate in both males and females. Thus, Tsix is not required at the onset of random X-inactivation; instead, it protects the active-X from ectopic silencing once X-inactivation has commenced.
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Affiliation(s)
- Srimonta Gayen
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI 48105, USA
| | - Emily Maclary
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI 48105, USA
| | - Emily Buttigieg
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI 48105, USA
| | - Michael Hinten
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI 48105, USA
| | - Sundeep Kalantry
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI 48105, USA.
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24
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Barakat TS, Ghazvini M, de Hoon B, Li T, Eussen B, Douben H, van der Linden R, van der Stap N, Boter M, Laven JS, Galjaard RJ, Grootegoed JA, de Klein A, Gribnau J. Stable X chromosome reactivation in female human induced pluripotent stem cells. Stem Cell Reports 2015; 4:199-208. [PMID: 25640760 PMCID: PMC4325229 DOI: 10.1016/j.stemcr.2014.12.012] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Revised: 12/22/2014] [Accepted: 12/27/2014] [Indexed: 01/01/2023] Open
Abstract
In placental mammals, balanced expression of X-linked genes is accomplished by X chromosome inactivation (XCI) in female cells. In humans, random XCI is initiated early during embryonic development. To investigate whether reprogramming of female human fibroblasts into induced pluripotent stem cells (iPSCs) leads to reactivation of the inactive X chromosome (Xi), we have generated iPSC lines from fibroblasts heterozygous for large X-chromosomal deletions. These fibroblasts show completely skewed XCI of the mutated X chromosome, enabling monitoring of X chromosome reactivation (XCR) and XCI using allele-specific single-cell expression analysis. This approach revealed that XCR is robust under standard culture conditions, but does not prevent reinitiation of XCI, resulting in a mixed population of cells with either two active X chromosomes (Xas) or one Xa and one Xi. This mixed population of XaXa and XaXi cells is stabilized in naive human stem cell medium, allowing expansion of clones with two Xas. Robust X chromosome reactivation in human iPSCs with large X-chromosomal deletions Female human iPSCs with two active X chromosomes Expansion of human iPSCs with two active X chromosomes in naive human stem cell medium
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Affiliation(s)
- Tahsin Stefan Barakat
- Department of Developmental Biology, Erasmus MC, University Medical Center, 3015 CE Rotterdam, the Netherlands
| | - Mehrnaz Ghazvini
- Department of Developmental Biology, Erasmus MC, University Medical Center, 3015 CE Rotterdam, the Netherlands; Erasmus Stem Cell and Regenerative Medicine Institute, Erasmus MC, University Medical Center, 3015 CE Rotterdam, the Netherlands
| | - Bas de Hoon
- Department of Developmental Biology, Erasmus MC, University Medical Center, 3015 CE Rotterdam, the Netherlands; Department of Obstetrics and Gynecology, Erasmus MC, University Medical Center, 3015 CE Rotterdam, the Netherlands
| | - Tracy Li
- Department of Developmental Biology, Erasmus MC, University Medical Center, 3015 CE Rotterdam, the Netherlands; Erasmus Stem Cell and Regenerative Medicine Institute, Erasmus MC, University Medical Center, 3015 CE Rotterdam, the Netherlands
| | - Bert Eussen
- Department of Clinical Genetics, Erasmus MC, University Medical Center, 3015 CE Rotterdam, the Netherlands
| | - Hannie Douben
- Department of Clinical Genetics, Erasmus MC, University Medical Center, 3015 CE Rotterdam, the Netherlands
| | - Reinier van der Linden
- Erasmus Stem Cell and Regenerative Medicine Institute, Erasmus MC, University Medical Center, 3015 CE Rotterdam, the Netherlands
| | - Nathalie van der Stap
- Department of Developmental Biology, Erasmus MC, University Medical Center, 3015 CE Rotterdam, the Netherlands; Erasmus Stem Cell and Regenerative Medicine Institute, Erasmus MC, University Medical Center, 3015 CE Rotterdam, the Netherlands
| | - Marjan Boter
- Department of Clinical Genetics, Erasmus MC, University Medical Center, 3015 CE Rotterdam, the Netherlands
| | - Joop S Laven
- Department of Obstetrics and Gynecology, Erasmus MC, University Medical Center, 3015 CE Rotterdam, the Netherlands
| | - Robert-Jan Galjaard
- Department of Clinical Genetics, Erasmus MC, University Medical Center, 3015 CE Rotterdam, the Netherlands
| | - J Anton Grootegoed
- Department of Developmental Biology, Erasmus MC, University Medical Center, 3015 CE Rotterdam, the Netherlands
| | - Annelies de Klein
- Department of Clinical Genetics, Erasmus MC, University Medical Center, 3015 CE Rotterdam, the Netherlands
| | - Joost Gribnau
- Department of Developmental Biology, Erasmus MC, University Medical Center, 3015 CE Rotterdam, the Netherlands.
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25
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Lau AC, Csankovszki G. Condensin-mediated chromosome organization and gene regulation. Front Genet 2015; 5:473. [PMID: 25628648 PMCID: PMC4292777 DOI: 10.3389/fgene.2014.00473] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Accepted: 12/19/2014] [Indexed: 11/13/2022] Open
Abstract
In many organisms sexual fate is determined by a chromosome-based method which entails a difference in sex chromosome-linked gene dosage. Consequently, a gene regulatory mechanism called dosage compensation equalizes X-linked gene expression between the sexes. Dosage compensation initiates as cells transition from pluripotency to differentiation. In Caenorhabditis elegans, dosage compensation is achieved by the dosage compensation complex (DCC) binding to both X chromosomes in hermaphrodites to downregulate gene expression by twofold. The DCC contains a subcomplex (condensin I(DC)) similar to the evolutionarily conserved condensin complexes which play a fundamental role in chromosome dynamics during mitosis. Therefore, mechanisms related to mitotic chromosome condensation are hypothesized to mediate dosage compensation. Consistent with this hypothesis, monomethylation of histone H4 lysine 20 is increased, whereas acetylation of histone H4 lysine 16 is decreased, both on mitotic chromosomes and on interphase dosage compensated X chromosomes in worms. These observations suggest that interphase dosage compensated X chromosomes maintain some characteristics associated with condensed mitotic chromosome. This chromosome state is stably propagated from one cell generation to the next. In this review we will speculate on how the biochemical activities of condensin can achieve both mitotic chromosome compaction and gene repression.
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Affiliation(s)
- Alyssa C Lau
- Department of Molecular, Cellular and Developmental Biology, University of Michigan Ann Arbor, MI, USA
| | - Györgyi Csankovszki
- Department of Molecular, Cellular and Developmental Biology, University of Michigan Ann Arbor, MI, USA
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26
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Barakat TS, Gribnau J. Generation of knockout alleles by RFLP based BAC targeting of polymorphic embryonic stem cells. Methods Mol Biol 2015; 1227:143-80. [PMID: 25239745 DOI: 10.1007/978-1-4939-1652-8_7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The isolation of germ line competent mouse Embryonic Stem (ES) cells and the ability to modify the genome by homologous recombination has revolutionized life science research. Since its initial discovery, several approaches have been introduced to increase the efficiency of homologous recombination, including the use of isogenic DNA for the generation of targeting constructs, and the use of Bacterial Artificial Chromosomes (BACs). BACs have the advantage of combining long stretches of homologous DNA, thereby increasing targeting efficiencies, with the possibilities delivered by BAC recombineering approaches, which provide the researcher with almost unlimited possibilities to efficiently edit the genome in a controlled fashion. Despite these advantages of BAC targeting approaches, a widespread use has been hampered, mainly because of the difficulties in identifying BAC-targeted knockout alleles by conventional methods like Southern Blotting. Recently, we introduced a novel BAC targeting strategy, in which Restriction Fragment Length Polymorphisms (RFLPs) are targeted in polymorphic mouse ES cells, enabling an efficient and easy PCR-based readout to identify properly targeted alleles. Here we provide a detailed protocol for the generation of targeting constructs, targeting of ES cells, and convenient PCR-based analysis of targeted clones, which enable the user to generate knockout ES cells of almost every gene in the mouse genome within a 2-month period.
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Affiliation(s)
- Tahsin Stefan Barakat
- Department of Reproduction and Development, Erasmus MC, University Medical Center, Room Ee 09-71, PO Box 2040, 3000 CA, Rotterdam, The Netherlands,
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27
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Lau AC, Nabeshima K, Csankovszki G. The C. elegans dosage compensation complex mediates interphase X chromosome compaction. Epigenetics Chromatin 2014; 7:31. [PMID: 25400696 PMCID: PMC4232692 DOI: 10.1186/1756-8935-7-31] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Accepted: 10/06/2014] [Indexed: 12/04/2022] Open
Abstract
Background Dosage compensation is a specialized gene regulatory mechanism which equalizes X-linked gene expression between sexes. In Caenorhabditis elegans, dosage compensation is achieved by the activity of the dosage compensation complex (DCC). The DCC localizes to both X chromosomes in hermaphrodites to downregulate gene expression by half. The DCC contains a subcomplex (condensin IDC) similar to the evolutionarily conserved condensin complexes which play fundamental roles in chromosome dynamics during mitosis and meiosis. Therefore, mechanisms related to mitotic chromosome condensation have been long hypothesized to mediate dosage compensation. However experimental evidence was lacking. Results Using 3D FISH microscopy to measure the volumes of X and chromosome I territories and to measure distances between individual loci, we show that hermaphrodite worms deficient in DCC proteins have enlarged interphase X chromosomes when compared to wild type. By contrast, chromosome I is unaffected. Interestingly, hermaphrodite worms depleted of condensin I or II show no phenotype. Therefore X chromosome compaction is specific to condensin IDC. In addition, we show that SET-1, SET-4, and SIR-2.1, histone modifiers whose activity is regulated by the DCC, need to be present for the compaction of the X chromosome territory. Conclusion These results support the idea that condensin IDC, and the histone modifications regulated by the DCC, mediate interphase X chromosome compaction. Our results link condensin-mediated chromosome compaction, an activity connected to mitotic chromosome condensation, to chromosome-wide repression of gene expression in interphase. Electronic supplementary material The online version of this article (doi:10.1186/1756-8935-7-31) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Alyssa C Lau
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109 Michigan
| | - Kentaro Nabeshima
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109 Michigan
| | - Györgyi Csankovszki
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI 48109 Michigan
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Cancer-like epigenetic derangements of human pluripotent stem cells and their impact on applications in regeneration and repair. Curr Opin Genet Dev 2014; 28:43-9. [PMID: 25461449 DOI: 10.1016/j.gde.2014.09.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Revised: 09/12/2014] [Accepted: 09/14/2014] [Indexed: 01/27/2023]
Abstract
A growing body of work has raised concern that many human pluripotent stem cell (hPSC) lines possess tumorigenic potential following differentiation to clinically relevant lineages. In this review, we highlight recent work characterizing the spectrum of cancer-like epigenetic derangements in human embryonic stem cells (hESC) and human induced pluripotent stem cells (hiPSC) that are associated with reprogramming errors or prolonged culture that may contribute to such tumorigenicity. These aberrations include cancer-like promoter DNA hypermethylation and histone marks associated with pluripotency, as well as aberrant X-chromosome regulation. We also feature recent work that suggests optimized high-fidelity reprogramming derivation methods can minimize cancer-associated epigenetic aberrations in hPSC, and thus ultimately improve the ultimate clinical utility of hiPSC in regenerative medicine.
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29
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Minkovsky A, Sahakyan A, Rankin-Gee E, Bonora G, Patel S, Plath K. The Mbd1-Atf7ip-Setdb1 pathway contributes to the maintenance of X chromosome inactivation. Epigenetics Chromatin 2014; 7:12. [PMID: 25028596 PMCID: PMC4099106 DOI: 10.1186/1756-8935-7-12] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2014] [Accepted: 06/05/2014] [Indexed: 01/08/2023] Open
Abstract
Background X chromosome inactivation (XCI) is a developmental program of heterochromatin formation that initiates during early female mammalian embryonic development and is maintained through a lifetime of cell divisions in somatic cells. Despite identification of the crucial long non-coding RNA Xist and involvement of specific chromatin modifiers in the establishment and maintenance of the heterochromatin of the inactive X chromosome (Xi), interference with known pathways only partially reactivates the Xi once silencing has been established. Here, we studied ATF7IP (MCAF1), a protein previously characterized to coordinate DNA methylation and histone H3K9 methylation through interactions with the methyl-DNA binding protein MBD1 and the histone H3K9 methyltransferase SETDB1, as a candidate maintenance factor of the Xi. Results We found that siRNA-mediated knockdown of Atf7ip in mouse embryonic fibroblasts (MEFs) induces the activation of silenced reporter genes on the Xi in a low number of cells. Additional inhibition of two pathways known to contribute to Xi maintenance, DNA methylation and Xist RNA coating of the X chromosome, strongly increased the number of cells expressing Xi-linked genes upon Atf7ip knockdown. Despite its functional importance in Xi maintenance, ATF7IP does not accumulate on the Xi in MEFs or differentiating mouse embryonic stem cells. However, we found that depletion of two known repressive biochemical interactors of ATF7IP, MBD1 and SETDB1, but not of other unrelated H3K9 methyltransferases, also induces the activation of an Xi-linked reporter in MEFs. Conclusions Together, these data indicate that Atf7ip acts in a synergistic fashion with DNA methylation and Xist RNA to maintain the silent state of the Xi in somatic cells, and that Mbd1 and Setdb1, similar to Atf7ip, play a functional role in Xi silencing. We therefore propose that ATF7IP links DNA methylation on the Xi to SETDB1-mediated H3K9 trimethylation via its interaction with MBD1, and that this function is a crucial feature of the stable silencing of the Xi in female mammalian cells.
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Affiliation(s)
- Alissa Minkovsky
- David Geffen School of Medicine, Department of Biological Chemistry, Jonsson Comprehensive Cancer Center, Molecular Biology Institute, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los Angeles, CA 90095, USA
| | - Anna Sahakyan
- David Geffen School of Medicine, Department of Biological Chemistry, Jonsson Comprehensive Cancer Center, Molecular Biology Institute, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los Angeles, CA 90095, USA
| | - Elyse Rankin-Gee
- David Geffen School of Medicine, Department of Biological Chemistry, Jonsson Comprehensive Cancer Center, Molecular Biology Institute, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los Angeles, CA 90095, USA
| | - Giancarlo Bonora
- David Geffen School of Medicine, Department of Biological Chemistry, Jonsson Comprehensive Cancer Center, Molecular Biology Institute, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los Angeles, CA 90095, USA
| | - Sanjeet Patel
- David Geffen School of Medicine, Department of Biological Chemistry, Jonsson Comprehensive Cancer Center, Molecular Biology Institute, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los Angeles, CA 90095, USA
| | - Kathrin Plath
- David Geffen School of Medicine, Department of Biological Chemistry, Jonsson Comprehensive Cancer Center, Molecular Biology Institute, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los Angeles, CA 90095, USA
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30
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Barakat TS, Gribnau J. Combined DNA-RNA fluorescent in situ hybridization (FISH) to study X chromosome inactivation in differentiated female mouse embryonic stem cells. J Vis Exp 2014. [PMID: 24961515 DOI: 10.3791/51628] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Fluorescent in situ hybridization (FISH) is a molecular technique which enables the detection of nucleic acids in cells. DNA FISH is often used in cytogenetics and cancer diagnostics, and can detect aberrations of the genome, which often has important clinical implications. RNA FISH can be used to detect RNA molecules in cells and has provided important insights in regulation of gene expression. Combining DNA and RNA FISH within the same cell is technically challenging, as conditions suitable for DNA FISH might be too harsh for fragile, single stranded RNA molecules. We here present an easily applicable protocol which enables the combined, simultaneous detection of Xist RNA and DNA encoded by the X chromosomes. This combined DNA-RNA FISH protocol can likely be applied to other systems where both RNA and DNA need to be detected.
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Affiliation(s)
| | - Joost Gribnau
- Department of Reproduction and Development, Erasmus MC - University Medical Center
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31
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Esworthy RS, Kim BW, Chow J, Shen B, Doroshow JH, Chu FF. Nox1 causes ileocolitis in mice deficient in glutathione peroxidase-1 and -2. Free Radic Biol Med 2014; 68:315-25. [PMID: 24374371 PMCID: PMC3943970 DOI: 10.1016/j.freeradbiomed.2013.12.018] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Revised: 12/14/2013] [Accepted: 12/17/2013] [Indexed: 02/06/2023]
Abstract
We previously reported that mice deficient in two Se-dependent glutathione peroxidases, GPx1 and GPx2, have spontaneous ileocolitis. Disease severity depends on mouse genetic background. Whereas C57BL/6J (B6) GPx1/2-double-knockout (DKO) mice have moderate ileitis and mild colitis, 129S1Svlm/J (129) DKO mice have severe ileocolitis. Because GPx's are antioxidant enzymes, we hypothesized that elevated reactive oxygen species trigger inflammation in these DKO mice. To test whether NADPH oxidase 1 (Nox1) contributes to colitis, we generated B6 triple-KO (TKO) mice to study their phenotype. Because the Nox1 gene is X-linked, we analyzed the effects of Nox1 on male B6 TKO mice and female B6 DKO mice with the Nox1(+/-) (het-TKO) genotype. We found that the male TKO and female het-TKO mice are virtually disease-free when monitored from 8 through 50 days of age. Male TKO and female het-TKO mice have nearly no signs of disease (e.g., lethargy and perianal alopecia) that are often exhibited in the DKO mice; further, the slower growth rate of DKO mice is almost completely eliminated in male TKO and female het-TKO mice. Male TKO and female het-TKO mice no longer have the shortened small intestine present in the DKO mice. Finally, the pathological characteristics of the DKO ileum, including the high level of crypt apoptosis (analyzed by apoptotic figures, TUNEL, and cleaved caspase-3 immunohistochemical staining), high numbers of Ki-67-positive crypt epithelium cells, and elevated levels of monocytes expressing myeloperoxidase, are all significantly decreased in male TKO mice. The attenuated ileal and colonic pathology is also evident in female het-DKO mice. Furthermore, the male DKO ileum has eightfold higher TNF cytokine levels than TKO ileum. Nox1 mRNA is highly elevated in both B6 and 129 DKO ileum compared to wild-type mouse ileum. Taking these results together, we propose that ileocolitis in the DKO mice is caused by Nox1, which is induced by TNF. The milder disease in female het-TKO intestine is probably due to random or imprinted X-chromosome inactivation, which produces mosaic Nox1 expression.
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Affiliation(s)
- Robert S Esworthy
- Department of Radiation Biology and Beckman Research Institute, City of Hope, Duarte, CA 91010, USA
| | - Byung-Wook Kim
- Irell & Manella Graduate School of Biological Sciences, Beckman Research Institute, City of Hope, Duarte, CA 91010, USA
| | - Joni Chow
- Department of Radiation Biology and Beckman Research Institute, City of Hope, Duarte, CA 91010, USA
| | - Binghui Shen
- Department of Radiation Biology and Beckman Research Institute, City of Hope, Duarte, CA 91010, USA
| | | | - Fong-Fong Chu
- Department of Radiation Biology and Beckman Research Institute, City of Hope, Duarte, CA 91010, USA.
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32
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Lan L, Nakajima S, Wei L, Sun L, Hsieh CL, Sobol RW, Bruchez M, Van Houten B, Yasui A, Levine AS. Novel method for site-specific induction of oxidative DNA damage reveals differences in recruitment of repair proteins to heterochromatin and euchromatin. Nucleic Acids Res 2013; 42:2330-45. [PMID: 24293652 PMCID: PMC3936713 DOI: 10.1093/nar/gkt1233] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Reactive oxygen species (ROS)-induced DNA damage is repaired by the base excision repair pathway. However, the effect of chromatin structure on BER protein recruitment to DNA damage sites in living cells is poorly understood. To address this problem, we developed a method to specifically produce ROS-induced DNA damage by fusing KillerRed (KR), a light-stimulated ROS-inducer, to a tet-repressor (tetR-KR) or a transcription activator (TA-KR). TetR-KR or TA-KR, bound to a TRE cassette (∼90 kb) integrated at a defined genomic locus in U2OS cells, was used to induce ROS damage in hetero- or euchromatin, respectively. We found that DNA glycosylases were efficiently recruited to DNA damage in heterochromatin, as well as in euchromatin. PARP1 was recruited to DNA damage within condensed chromatin more efficiently than in active chromatin. In contrast, recruitment of FEN1 was highly enriched at sites of DNA damage within active chromatin in a PCNA- and transcription activation-dependent manner. These results indicate that oxidative DNA damage is differentially processed within hetero or euchromatin.
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Affiliation(s)
- Li Lan
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA, University of Pittsburgh Cancer Institute, University of Pittsburgh School of Medicine, 5117 Centre Avenue, Pittsburgh, PA 15213, USA, School of Medicine, Tsinghua University, No.1 Tsinghua Yuan, Haidian District, Beijing 100084, People's Republic of China, Department of Pharmacology & Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA, Department of Human Genetics, University of Pittsburgh Graduate School of Public Health, Pittsburgh, PA 15213, USA, Department of Chemistry and Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA and Division of Dynamic Proteome, Institute of Development, Aging, and Cancer, Tohoku University, Seiryomachi 4-1, Sendai 980-8575, Japan
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33
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Payer B, Rosenberg M, Yamaji M, Yabuta Y, Koyanagi-Aoi M, Hayashi K, Yamanaka S, Saitou M, Lee JT. Tsix RNA and the germline factor, PRDM14, link X reactivation and stem cell reprogramming. Mol Cell 2013; 52:805-18. [PMID: 24268575 DOI: 10.1016/j.molcel.2013.10.023] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Revised: 09/05/2013] [Accepted: 10/16/2013] [Indexed: 10/26/2022]
Abstract
Transitions between pluripotent and differentiated states are marked by dramatic epigenetic changes. Cellular differentiation is tightly linked to X chromosome inactivation (XCI), whereas reprogramming to induced pluripotent stem cells (iPSCs) is associated with X chromosome reactivation (XCR). XCR reverses the silent state of the inactive X, occurring in mouse blastocysts and germ cells. In spite of its importance, little is known about underlying mechanisms. Here, we examine the role of the long noncoding Tsix RNA and the germline factor, PRDM14. In blastocysts, XCR is perturbed by mutation of either Tsix or Prdm14. In iPSCs, XCR is disrupted only by PRDM14 deficiency, which also affects iPSC derivation and maintenance. We show that Tsix and PRDM14 directly link XCR to pluripotency: first, PRDM14 represses Rnf12 by recruiting polycomb repressive complex 2; second, Tsix enables PRDM14 to bind Xist. Thus, our study provides functional and mechanistic links between cellular and X chromosome reprogramming.
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Affiliation(s)
- Bernhard Payer
- Howard Hughes Medical Institute, Boston, MA 02114, USA; Department of Genetics, Harvard Medical School, Boston, MA 02114, USA; Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Michael Rosenberg
- Howard Hughes Medical Institute, Boston, MA 02114, USA; Department of Genetics, Harvard Medical School, Boston, MA 02114, USA; Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Masashi Yamaji
- Department of Anatomy and Cell Biology, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan; JST, ERATO, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Yukihiro Yabuta
- Department of Anatomy and Cell Biology, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan; JST, ERATO, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Michiyo Koyanagi-Aoi
- Center for iPS Cell Research and Application, Kyoto University, 53 Kawahara-cho, Shogoin Yoshida, Sakyo-ku, Kyoto 606-8507, Japan
| | - Katsuhiko Hayashi
- Department of Anatomy and Cell Biology, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan; Center for iPS Cell Research and Application, Kyoto University, 53 Kawahara-cho, Shogoin Yoshida, Sakyo-ku, Kyoto 606-8507, Japan; JST, PRESTO, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Shinya Yamanaka
- Center for iPS Cell Research and Application, Kyoto University, 53 Kawahara-cho, Shogoin Yoshida, Sakyo-ku, Kyoto 606-8507, Japan; Gladstone Institute of Cardiovascular Disease, San Francisco, CA 94158, USA
| | - Mitinori Saitou
- Department of Anatomy and Cell Biology, Graduate School of Medicine, Kyoto University, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan; JST, ERATO, Yoshida-Konoe-cho, Sakyo-ku, Kyoto 606-8501, Japan; Center for iPS Cell Research and Application, Kyoto University, 53 Kawahara-cho, Shogoin Yoshida, Sakyo-ku, Kyoto 606-8507, Japan; Institute for Integrated Cell-Material Sciences, Kyoto University, Yoshida-Ushinomiya-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Jeannie T Lee
- Howard Hughes Medical Institute, Boston, MA 02114, USA; Department of Genetics, Harvard Medical School, Boston, MA 02114, USA; Department of Molecular Biology, Massachusetts General Hospital, Boston, MA 02114, USA.
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34
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Custer LM, Snyder MJ, Flegel K, Csankovszki G. The onset of C. elegans dosage compensation is linked to the loss of developmental plasticity. Dev Biol 2013; 385:279-90. [PMID: 24252776 DOI: 10.1016/j.ydbio.2013.11.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Revised: 09/17/2013] [Accepted: 11/03/2013] [Indexed: 12/29/2022]
Abstract
Dosage compensation (DC) equalizes X-linked gene expression between sexes. In Caenorhabditis elegans, the dosage compensation complex (DCC) localizes to both X chromosomes in hermaphrodites and downregulates gene expression 2-fold. The DCC first localizes to hermaphrodite X chromosomes at the 30-cell stage, coincident with a developmental transition from plasticity to differentiation. To test whether DC onset is linked to loss of developmental plasticity, we established a timeline for the accumulation of DC-mediated chromatin features on X (depletion of histone H4 lysine 16 acetylation (H4K16ac) and enrichment of H4K20 monomethylation (H4K20me1)) in both wild type and developmentally delayed embryos. Surprisingly, we found that H4K16ac is depleted from the X even before the 30-cell stage in a DCC-independent manner. This depletion requires the activities of MES-2, MES-3, and MES-6 (a complex similar to the Polycomb Repressive Complex 2), and MES-4. By contrast, H4K20me1 becomes enriched on X chromosomes several cell cycles after DCC localization to the X, suggesting that it is a late mark in DC. MES-2 also promotes differentiation, and mes-2 mutant embryos exhibit prolonged developmental plasticity. Consistent with the hypothesis that the onset of DC is linked to differentiation, DCC localization and H4K20me1 accumulation on the X chromosomes are delayed in mes mutant hermaphrodite embryos. Furthermore, the onset of hermaphrodite-specific transcription of sdc-2 (which triggers DC) is delayed in mes-2 mutants. We propose that as embryonic blastomeres lose their developmental plasticity, hermaphrodite X chromosomes transition from a MES protein-regulated state to DCC-mediated repression.
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Affiliation(s)
- Laura M Custer
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, 830 N. University Ave., Ann Arbor, MI 48109-1048, USA
| | - Martha J Snyder
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, 830 N. University Ave., Ann Arbor, MI 48109-1048, USA
| | - Kerry Flegel
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, 830 N. University Ave., Ann Arbor, MI 48109-1048, USA
| | - Györgyi Csankovszki
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, 830 N. University Ave., Ann Arbor, MI 48109-1048, USA.
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35
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Mao J, Zhang Q, Ye X, Liu K, Liu L. Efficient induction of pluripotent stem cells from granulosa cells by Oct4 and Sox2. Stem Cells Dev 2013; 23:779-89. [PMID: 24083387 DOI: 10.1089/scd.2013.0325] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Various types of somatic cells can be reprogrammed to induced pluripotent stem (iPS) cells. Somatic stem cells exhibit enhanced reprogramming efficiency by fewer factors, in contrast to fully differentiated cells. Nuclear LaminA is highly expressed in differentiated cells, and stem cells are characterized by the absence of LaminA. Granulosa cells (GCs) and cumulus cells in the ovarian follicles effectively and firstly generated cloned mice by somatic cell nuclear transfer, and these cells lack LaminA expression. We tested the hypothesis that GCs could be effectively used to generate iPS cells with fewer factors. We show that iPS cells are generated from GCs at high efficiency even with only two factors, Oct4 and Sox2, like the iPS cells generated using four Yamanaka factors. These iPS cells show pluripotency in vitro and in vivo, as evidenced by high expression of pluripotency-associated genes, Oct4, Nanog, and SSEA-1, differentiation into three embryonic germ layers by embryoid body formation and teratoma tests, as well as high efficient generation of chimeras. Moreover, the exogenous genes are effectively silenced in these iPS cells. These data provide additional evidence in supporting the notion that reduced expression of LaminA and stem cells can improve the reprogramming efficiency to pluripotency.
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Affiliation(s)
- Jian Mao
- State Key Laboratory of Medicinal Chemical Biology, Department of Cell Biology and Genetics, College of Life Sciences, Nankai University , Tianjin, China
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36
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Biechele S, Adissu HA, Cox BJ, Rossant J. Zygotic Porcn paternal allele deletion in mice to model human focal dermal hypoplasia. PLoS One 2013; 8:e79139. [PMID: 24223895 PMCID: PMC3815152 DOI: 10.1371/journal.pone.0079139] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Accepted: 09/18/2013] [Indexed: 11/19/2022] Open
Abstract
In mouse and humans, the X-chromosomal Porcupine homolog (Porcn) gene is required for the acylation and secretion of all 19 Wnt ligands, thus representing a bottleneck in the secretion of Wnt ligands. In humans, mutations in PORCN cause the X-linked dominant syndrome Focal Dermal Hypoplasia (FDH, OMIM#305600). This disorder is characterized by ecto-mesodermal dysplasias and shows a highly variable phenotype, potentially due to individual X chromosome inactivation patterns. To improve the understanding of human FDH, we have established a mouse model by generation of Porcn heterozygous animals carrying a zygotic deletion of the paternal allele. We show that heterozygous female fetuses display variable defects that do not significantly affect survival in the uterus, but lead to perinatal lethality in more than 95% of females. Rare survivors develop to adulthood and display variable skeletal and skin defects, representing an adult zygotic mouse model for human FDH. Although not frequently reported in humans, we also observed bronchopneumonia, rhinitis, and otitis media in these animals, suggesting a potential link between Porcn function and the normal development of ciliated cells in these tissues.
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Affiliation(s)
- Steffen Biechele
- Program in Developmental and Stem Cell Biology, Hospital for Sick Children Research Institute, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Hibret A. Adissu
- Physiology & Experimental Medicine, the Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Laboratory Medicine and Pathobiology, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Brian J. Cox
- Program in Developmental and Stem Cell Biology, Hospital for Sick Children Research Institute, Toronto, Ontario, Canada
| | - Janet Rossant
- Program in Developmental and Stem Cell Biology, Hospital for Sick Children Research Institute, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- * E-mail:
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37
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Jäger N, Schlesner M, Jones DTW, Raffel S, Mallm JP, Junge KM, Weichenhan D, Bauer T, Ishaque N, Kool M, Northcott PA, Korshunov A, Drews RM, Koster J, Versteeg R, Richter J, Hummel M, Mack SC, Taylor MD, Witt H, Swartman B, Schulte-Bockholt D, Sultan M, Yaspo ML, Lehrach H, Hutter B, Brors B, Wolf S, Plass C, Siebert R, Trumpp A, Rippe K, Lehmann I, Lichter P, Pfister SM, Eils R. Hypermutation of the inactive X chromosome is a frequent event in cancer. Cell 2013; 155:567-81. [PMID: 24139898 PMCID: PMC3898475 DOI: 10.1016/j.cell.2013.09.042] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2013] [Revised: 08/02/2013] [Accepted: 09/20/2013] [Indexed: 11/26/2022]
Abstract
Mutation is a fundamental process in tumorigenesis. However, the degree to which the rate of somatic mutation varies across the human genome and the mechanistic basis underlying this variation remain to be fully elucidated. Here, we performed a cross-cancer comparison of 402 whole genomes comprising a diverse set of childhood and adult tumors, including both solid and hematopoietic malignancies. Surprisingly, we found that the inactive X chromosome of many female cancer genomes accumulates on average twice and up to four times as many somatic mutations per megabase, as compared to the individual autosomes. Whole-genome sequencing of clonally expanded hematopoietic stem/progenitor cells (HSPCs) from healthy individuals and a premalignant myelodysplastic syndrome (MDS) sample revealed no X chromosome hypermutation. Our data suggest that hypermutation of the inactive X chromosome is an early and frequent feature of tumorigenesis resulting from DNA replication stress in aberrantly proliferating cells. X chromosome has up to 4× more mutations than the autosomes in female cancer genomes Hypermutations only affect the inactive X chromosome X hypermutation involves somatic point mutations and indels, but not germline mutations No X hypermutation is found in clonal expansions of normal or premalignant cells
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Affiliation(s)
- Natalie Jäger
- Division of Theoretical Bioinformatics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany
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38
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Cao F, Fukuda A, Watanabe H, Kono T. The transcriptomic architecture of mouse Sertoli cell clone embryos reveals temporal–spatial-specific reprogramming. Reproduction 2013; 145:277-88. [PMID: 23580949 PMCID: PMC3607486 DOI: 10.1530/rep-12-0435] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Somatic cell nuclear transfer, a technique used to generate clone embryos by transferring the nucleus of a somatic cell into an enucleated oocyte, is an excellent approach to study the reprogramming of the nuclei of differentiated cells. Here, we conducted a transcriptomic study by performing microarray analysis on single Sertoli cell nuclear transfer (SeCNT) embryos throughout preimplantation development. The extensive data collected from the oocyte to the blastocyst stage helped to identify specific genes that were incorrectly reprogrammed at each stage, thereby providing a novel perspective for understanding reprogramming progression in SeCNT embryos.This attempt provided an opportunity to discuss the possibility that ectopic gene expression could be involved in the developmental failure of SeCNT embryos. Network analysis at each stage suggested that in total, 127 networks were involved in developmental and functional disorders in SeCNT embryos. Furthermore, chromosome mapping using our time-lapse expression data highlighted temporal–spatial changes of the abnormal expression, showing the characteristic distribution of the genes on each chromosome.Thus, the present study revealed that the preimplantation development of SeCNT embryos appears normal; however, the progression of incorrect reprogramming is concealed throughout development.
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Affiliation(s)
- Feng Cao
- Department of Bioscience, Tokyo University of Agriculture, Setagaya-ku, Tokyo 156-8502, Japan
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39
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Biechele S, Cockburn K, Lanner F, Cox BJ, Rossant J. Porcn-dependent Wnt signaling is not required prior to mouse gastrulation. Development 2013; 140:2961-71. [PMID: 23760955 DOI: 10.1242/dev.094458] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
In mice and humans the X-chromosomal porcupine homolog (Porcn) gene is required for the acylation and secretion of all 19 Wnt ligands and thus represents a bottleneck for all Wnt signaling. We have generated a mouse line carrying a floxed allele for Porcn and used zygotic, oocyte-specific and visceral endoderm-specific deletions to investigate embryonic and extra-embryonic requirements for Wnt ligand secretion. We show that there is no requirement for Porcn-dependent secretion of Wnt ligands during preimplantation development of the mouse embryo. Porcn-dependent Wnts are first required for the initiation of gastrulation, where Porcn function is required in the epiblast but not the visceral endoderm. Heterozygous female embryos, which are mutant in both trophoblast and visceral endoderm due to imprinted X chromosome inactivation, complete gastrulation but display chorio-allantoic fusion defects similar to Wnt7b mutants. Our studies highlight the importance of Wnt3 and Wnt7b for embryonic and placental development but suggest that endogenous Porcn-dependent Wnt secretion does not play an essential role in either implantation or blastocyst lineage specification.
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Affiliation(s)
- Steffen Biechele
- Program in Developmental and Stem Cell Biology, Hospital for Sick Children Research Institute, Toronto, ON M5G 1X8, Canada
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40
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Regulation of Mammalian Gene Dosage by Long Noncoding RNAs. Biomolecules 2013; 3:124-42. [PMID: 24970160 PMCID: PMC4030888 DOI: 10.3390/biom3010124] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Revised: 01/23/2013] [Accepted: 01/25/2013] [Indexed: 12/14/2022] Open
Abstract
Recent transcriptome studies suggest that long noncoding RNAs (lncRNAs) are key components of the mammalian genome, and their study has become a new frontier in biomedical research. In fact, lncRNAs in the mammalian genome were identified and studied at particular epigenetic loci, including imprinted loci and X-chromosome inactivation center, at least two decades ago—long before development of high throughput sequencing technology. Since then, researchers have found that lncRNAs play essential roles in various biological processes, mostly during development. Since much of our understanding of lncRNAs originates from our knowledge of these well-established lncRNAs, in this review we will focus on lncRNAs from the X-chromosome inactivation center and the Dlk1-Dio3 imprinted cluster as examples of lncRNA mechanisms functioning in the epigenetic regulation of mammalian genes.
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Oikawa M, Matoba S, Inoue K, Kamimura S, Hirose M, Ogonuki N, Shiura H, Sugimoto M, Abe K, Ishino F, Ogura A. RNAi-mediated knockdown of Xist does not rescue the impaired development of female cloned mouse embryos. J Reprod Dev 2013; 59:231-7. [PMID: 23363561 PMCID: PMC3934135 DOI: 10.1262/jrd.2012-195] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
In mice, one of the major epigenetic errors associated with somatic cell nuclear
transfer (SCNT) is ectopic expression of Xist during the preimplantation
period in both sexes. We found that this aberrant Xist expression could
be impeded by deletion of Xist from the putative active X chromosome in
donor cells. In male clones, it was also found that prior injection of
Xist-specific siRNA could significantly improve the postimplantation
development of cloned embryos as a result of a significant repression of
Xist at the morula stage. In this study, we examined whether the same
knockdown strategy could work as well in female SCNT-derived embryos. Embryos were
reconstructed with cumulus cell nuclei and injected with Xist-specific
siRNA at 6–7 h after oocyte activation. RNA FISH analysis revealed that siRNA treatment
successfully repressed Xist RNA at the morula stage, as shown by the
significant decrease in the number of cloud-type Xist signals in the
blastomere nuclei. However, blastomeres with different sizes (from “pinpoint” to “cloud”)
and numbers of Xist RNA signals remained within single embryos. After
implantation, the dysregulated Xist expression was normalized
autonomously, as in male clones, to a state of monoallelic expression in both embryonic
and extraembryonic tissues. However, at term there was no significant improvement in the
survival of the siRNA-injected cloned embryos. Thus, siRNA injection was largely effective
in repressing the Xist overexpression in female cloned embryos but failed
to rescue them, probably because of an inability to mimic consistent monoallelic
Xist expression in these embryos. This could only be achieved in female
embryos by applying a gene knockout strategy rather than an siRNA approach.
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Affiliation(s)
- Mami Oikawa
- RIKEN BioResource Center, Ibaraki 305-0074, Japan
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42
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Guibert S, Weber M. Functions of DNA Methylation and Hydroxymethylation in Mammalian Development. Curr Top Dev Biol 2013; 104:47-83. [DOI: 10.1016/b978-0-12-416027-9.00002-4] [Citation(s) in RCA: 125] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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