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Ramesh R, Manurung Y, Ma KH, Blakely T, Won S, Moreno-Ramos OA, Wyatt E, Awatramani R, Svaren J. JUN Regulation of Injury-Induced Enhancers in Schwann Cells. J Neurosci 2022; 42:6506-6517. [PMID: 35906072 PMCID: PMC9410756 DOI: 10.1523/jneurosci.2533-21.2022] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Revised: 06/22/2022] [Accepted: 07/14/2022] [Indexed: 11/21/2022] Open
Abstract
Schwann cells play a critical role after peripheral nerve injury by clearing myelin debris, forming axon-guiding bands of Büngner, and remyelinating regenerating axons. Schwann cells undergo epigenomic remodeling to differentiate into a repair state that expresses unique genes, some of which are not expressed at other stages of Schwann cell development. We previously identified a set of enhancers that are activated in Schwann cells after nerve injury, and we determined whether these enhancers are preprogrammed into the Schwann cell epigenome as poised enhancers before injury. Poised enhancers share many attributes of active enhancers, such as open chromatin, but are marked by repressive histone H3 lysine 27 (H3K27) trimethylation rather than H3K27 acetylation. We find that most injury-induced enhancers are not marked as poised enhancers before injury indicating that injury-induced enhancers are not preprogrammed in the Schwann cell epigenome. Injury-induced enhancers are enriched with AP-1 binding motifs, and the c-JUN subunit of AP-1 had been shown to be critical to drive the transcriptional response of Schwann cells after injury. Using in vivo chromatin immunoprecipitation sequencing analysis in rat, we find that c-JUN binds to a subset of injury-induced enhancers. To test the role of specific injury-induced enhancers, we focused on c-JUN-binding enhancers upstream of the Sonic hedgehog (Shh) gene, which is only upregulated in repair Schwann cells compared with other stages of Schwann cell development. We used targeted deletions in male/female mice to show that the enhancers are required for robust induction of the Shh gene after injury.SIGNIFICANCE STATEMENT The proregenerative actions of Schwann cells after nerve injury depends on profound reprogramming of the epigenome. The repair state is directed by injury-induced transcription factors, like JUN, which is uniquely required after nerve injury. In this study, we test whether the injury program is preprogrammed into the epigenome as poised enhancers and define which enhancers bind JUN. Finally, we test the roles of these enhancers by performing clustered regularly interspaced short palindromic repeat (CRISPR)-mediated deletion of JUN-bound injury enhancers in the Sonic hedgehog gene. Although many long-range enhancers drive expression of Sonic hedgehog at different developmental stages of specific tissues, these studies identify an entirely new set of enhancers that are required for Sonic hedgehog induction in Schwann cells after injury.
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Affiliation(s)
- Raghu Ramesh
- Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin 53705
- Comparative Biomedical Sciences Graduate Program, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53706
| | - Yanti Manurung
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611
| | - Ki H Ma
- Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin 53705
| | - Todd Blakely
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611
| | - Seongsik Won
- Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin 53705
| | - Oscar Andrés Moreno-Ramos
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611
| | - Eugene Wyatt
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611
| | - Rajeshwar Awatramani
- Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611
| | - John Svaren
- Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin 53705
- Comparative Biomedical Sciences Graduate Program, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin 53706
- Department of Comparative Biosciences, School of Veterinary Medicine University of Wisconsin-Madison, Madison, Wisconsin 53705
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2
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Arthur-Farraj P, Coleman MP. Lessons from Injury: How Nerve Injury Studies Reveal Basic Biological Mechanisms and Therapeutic Opportunities for Peripheral Nerve Diseases. Neurotherapeutics 2021; 18:2200-2221. [PMID: 34595734 PMCID: PMC8804151 DOI: 10.1007/s13311-021-01125-3] [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] [Accepted: 09/07/2021] [Indexed: 12/25/2022] Open
Abstract
Since Waller and Cajal in the nineteenth and early twentieth centuries, laboratory traumatic peripheral nerve injury studies have provided great insight into cellular and molecular mechanisms governing axon degeneration and the responses of Schwann cells, the major glial cell type of peripheral nerves. It is now evident that pathways underlying injury-induced axon degeneration and the Schwann cell injury-specific state, the repair Schwann cell, are relevant to many inherited and acquired disorders of peripheral nerves. This review provides a timely update on the molecular understanding of axon degeneration and formation of the repair Schwann cell. We discuss how nicotinamide mononucleotide adenylyltransferase 2 (NMNAT2) and sterile alpha TIR motif containing protein 1 (SARM1) are required for axon survival and degeneration, respectively, how transcription factor c-JUN is essential for the Schwann cell response to nerve injury and what each tells us about disease mechanisms and potential therapies. Human genetic association with NMNAT2 and SARM1 strongly suggests aberrant activation of programmed axon death in polyneuropathies and motor neuron disorders, respectively, and animal studies suggest wider involvement including in chemotherapy-induced and diabetic neuropathies. In repair Schwann cells, cJUN is aberrantly expressed in a wide variety of human acquired and inherited neuropathies. Animal models suggest it limits axon loss in both genetic and traumatic neuropathies, whereas in contrast, Schwann cell secreted Neuregulin-1 type 1 drives onion bulb pathology in CMT1A. Finally, we discuss opportunities for drug-based and gene therapies to prevent axon loss or manipulate the repair Schwann cell state to treat acquired and inherited neuropathies and neuronopathies.
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Affiliation(s)
- Peter Arthur-Farraj
- Department of Clinical Neurosciences, John Van Geest Centre for Brain Repair, University of Cambridge, Robinson Way, Cambridge, CB2 0PY, UK.
| | - Michael P Coleman
- Department of Clinical Neurosciences, John Van Geest Centre for Brain Repair, University of Cambridge, Robinson Way, Cambridge, CB2 0PY, UK.
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3
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Chang J, Lurie RH, Sharma A, Bashir M, Fung CM, Dettman RW, Dizon MLV. Intrauterine growth restriction followed by oxygen support uniquely interferes with genetic regulators of myelination. eNeuro 2021; 8:ENEURO.0263-20.2021. [PMID: 34099489 PMCID: PMC8266217 DOI: 10.1523/eneuro.0263-20.2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 03/23/2021] [Accepted: 04/23/2021] [Indexed: 12/24/2022] Open
Abstract
Intrauterine growth restriction (IUGR) and oxygen exposure in isolation and combination adversely affect the developing brain, putting infants at risk for neurodevelopmental disability including cerebral palsy. Rodent models of IUGR and postnatal hyperoxia have demonstrated oligodendroglial injury with subsequent white matter injury (WMI) and motor dysfunction. Here we investigate transcriptomic dysregulation in IUGR with and without hyperoxia exposure to account for the abnormal brain structure and function previously documented. We performed RNA sequencing and analysis using a mouse model of IUGR and found that IUGR, hyperoxia, and the combination of IUGR with hyperoxia (IUGR/hyperoxia) produced distinct changes in gene expression. IUGR in isolation demonstrated the fewest differentially expressed genes compared to control. In contrast, we detected several gene alterations in IUGR/hyperoxia; genes involved in myelination were strikingly downregulated. We also identified changes to specific regulators including TCF7L2, BDNF, SOX2, and DGCR8, through Ingenuity Pathway Analysis, that may contribute to impaired myelination in IUGR/hyperoxia. Our findings show that IUGR with hyperoxia induces unique transcriptional changes in the developing brain. These indicate mechanisms for increased risk for WMI in IUGR infants exposed to oxygen and suggest potential therapeutic targets to improve motor outcomes.Significance StatementThis study demonstrates that perinatal exposures of IUGR and/or postnatal hyperoxia result in distinct transcriptomic changes in the developing brain. In particular, we found that genes involved in normal developmental myelination, myelin maintenance, and remyelination were most dysregulated when IUGR was combined with hyperoxia. Understanding how multiple risk factors lead to WMI is the first step in developing future therapeutic interventions. Additionally, because oxygen exposure is often unavoidable after birth, an understanding of gene perturbations in this setting will increase our awareness of the need for tight control of oxygen use to minimize future motor disability.
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Affiliation(s)
- Jill Chang
- Children's Hospital of Chicago, Department of Pediatrics, Division of Neonatology, Chicago, Illinois, USA
| | - Robert H Lurie
- Children's Hospital of Chicago, Department of Pediatrics, Division of Neonatology, Chicago, Illinois, USA
| | - Abhineet Sharma
- Children's Hospital of Chicago, Department of Pediatrics, Division of Neonatology, Chicago, Illinois, USA
| | - Mirrah Bashir
- Children's Hospital of Chicago, Department of Pediatrics, Division of Neonatology, Chicago, Illinois, USA
| | - Camille M Fung
- University of Utah, Department of Pediatrics, Salt Lake City, Utah, USA
| | - Robert W Dettman
- Children's Hospital of Chicago, Department of Pediatrics, Division of Neonatology, Chicago, Illinois, USA
| | - Maria L V Dizon
- Children's Hospital of Chicago, Department of Pediatrics, Division of Neonatology, Chicago, Illinois, USA
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4
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Duong P, Ma KH, Ramesh R, Moran JJ, Won S, Svaren J. H3K27 demethylases are dispensable for activation of Polycomb-regulated injury response genes in peripheral nerve. J Biol Chem 2021; 297:100852. [PMID: 34090875 PMCID: PMC8258988 DOI: 10.1016/j.jbc.2021.100852] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 05/26/2021] [Accepted: 06/01/2021] [Indexed: 11/19/2022] Open
Abstract
The induction of nerve injury response genes in Schwann cells depends on both transcriptional and epigenomic reprogramming. The nerve injury response program is regulated by the repressive histone mark H3K27 trimethylation (H3K27me3), deposited by Polycomb repressive complex 2 (PRC2). Loss of PRC2 function leads to early and augmented induction of the injury response gene network in peripheral nerves, suggesting H3K27 demethylases are required for derepression of Polycomb-regulated nerve injury genes. To determine the function of H3K27 demethylases in nerve injury, we generated Schwann cell-specific knockouts of H3K27 demethylase Kdm6b and double knockouts of Kdm6b/Kdm6a (encoding JMJD3 and UTX). We found that H3K27 demethylases are largely dispensable for Schwann cell development and myelination. In testing the function of H3K27 demethylases after injury, we found early induction of some nerve injury genes was diminished compared with control, but most injury genes were largely unaffected at 1 and 7 days post injury. Although it was proposed that H3K27 demethylases are required to activate expression of the cyclin-dependent kinase inhibitor Cdkn2a in response to injury, Schwann cell-specific deletion of H3K27 demethylases affected neither the expression of this gene nor Schwann cell proliferation after nerve injury. To further characterize the regulation of nerve injury response genes, we found that injury genes are associated with repressive histone H2AK119 ubiquitination catalyzed by PRC1, which declines after injury. Overall, our results indicate H3K27 demethylation is not required for induction of injury response genes and that other mechanisms likely are involved in activating Polycomb-repressed injury genes in peripheral nerve.
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Affiliation(s)
- Phu Duong
- Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin, USA; Cellular and Molecular Pathology Graduate Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Ki H Ma
- Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin, USA; Cellular and Molecular Pathology Graduate Program, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Raghu Ramesh
- Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - John J Moran
- Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Seongsik Won
- Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - John Svaren
- Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin, USA; Department of Comparative Biosciences, University of Wisconsin-Madison, Madison, Wisconsin, USA.
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5
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Fornaro M, Marcus D, Rattin J, Goral J. Dynamic Environmental Physical Cues Activate Mechanosensitive Responses in the Repair Schwann Cell Phenotype. Cells 2021; 10:cells10020425. [PMID: 33671410 PMCID: PMC7922665 DOI: 10.3390/cells10020425] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 02/09/2021] [Accepted: 02/11/2021] [Indexed: 01/10/2023] Open
Abstract
Schwann cells plastically change in response to nerve injury to become a newly reconfigured repair phenotype. This cell is equipped to sense and interact with the evolving and unusual physical conditions characterizing the injured nerve environment and activate intracellular adaptive reprogramming as a consequence of external stimuli. Summarizing the literature contributions on this matter, this review is aimed at highlighting the importance of the environmental cues of the regenerating nerve as key factors to induce morphological and functional changes in the Schwann cell population. We identified four different microenvironments characterized by physical cues the Schwann cells sense via interposition of the extracellular matrix. We discussed how the physical cues of the microenvironment initiate changes in Schwann cell behavior, from wrapping the axon to becoming a multifunctional denervated repair cell and back to reestablishing contact with regenerated axons.
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Affiliation(s)
- Michele Fornaro
- Department of Anatomy, College of Graduate Studies (CGS), Midwestern University, Downers Grove, IL 60515, USA;
- Department of Anatomy, Chicago College of Osteopathic Medicine (CCOM), Midwestern University, Downers Grove, IL 60515, USA; (D.M.); (J.R.)
- Correspondence: ; Tel.: +001-630-515-6055
| | - Dominic Marcus
- Department of Anatomy, Chicago College of Osteopathic Medicine (CCOM), Midwestern University, Downers Grove, IL 60515, USA; (D.M.); (J.R.)
| | - Jacob Rattin
- Department of Anatomy, Chicago College of Osteopathic Medicine (CCOM), Midwestern University, Downers Grove, IL 60515, USA; (D.M.); (J.R.)
| | - Joanna Goral
- Department of Anatomy, College of Graduate Studies (CGS), Midwestern University, Downers Grove, IL 60515, USA;
- Department of Anatomy, Chicago College of Osteopathic Medicine (CCOM), Midwestern University, Downers Grove, IL 60515, USA; (D.M.); (J.R.)
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6
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Wagstaff LJ, Gomez-Sanchez JA, Fazal SV, Otto GW, Kilpatrick AM, Michael K, Wong LYN, Ma KH, Turmaine M, Svaren J, Gordon T, Arthur-Farraj P, Velasco-Aviles S, Cabedo H, Benito C, Mirsky R, Jessen KR. Failures of nerve regeneration caused by aging or chronic denervation are rescued by restoring Schwann cell c-Jun. eLife 2021; 10:e62232. [PMID: 33475496 PMCID: PMC7819709 DOI: 10.7554/elife.62232] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 12/21/2020] [Indexed: 02/06/2023] Open
Abstract
After nerve injury, myelin and Remak Schwann cells reprogram to repair cells specialized for regeneration. Normally providing strong regenerative support, these cells fail in aging animals, and during chronic denervation that results from slow axon growth. This impairs axonal regeneration and causes significant clinical problems. In mice, we find that repair cells express reduced c-Jun protein as regenerative support provided by these cells declines during aging and chronic denervation. In both cases, genetically restoring Schwann cell c-Jun levels restores regeneration to control levels. We identify potential gene candidates mediating this effect and implicate Shh in the control of Schwann cell c-Jun levels. This establishes that a common mechanism, reduced c-Jun in Schwann cells, regulates success and failure of nerve repair both during aging and chronic denervation. This provides a molecular framework for addressing important clinical problems, suggesting molecular pathways that can be targeted to promote repair in the PNS.
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Affiliation(s)
- Laura J Wagstaff
- Department of Cell and Developmental Biology, University College LondonLondonUnited Kingdom
| | - Jose A Gomez-Sanchez
- Instituto de Neurociencias de Alicante, Universidad Miguel Hernández‐CSICSan Juan de AlicanteSpain
| | - Shaline V Fazal
- Department of Cell and Developmental Biology, University College LondonLondonUnited Kingdom
| | - Georg W Otto
- University College London Great Ormond Street Institute of Child HealthLondonUnited Kingdom
| | - Alastair M Kilpatrick
- Centre for Regenerative Medicine, Institute for Regeneration and Repair, University of EdinburghEdinburghUnited Kingdom
| | - Kirolos Michael
- Department of Cell and Developmental Biology, University College LondonLondonUnited Kingdom
| | - Liam YN Wong
- Department of Cell and Developmental Biology, University College LondonLondonUnited Kingdom
| | - Ki H Ma
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin‐MadisonMadisonUnited States
| | - Mark Turmaine
- Department of Cell and Developmental Biology, University College LondonLondonUnited Kingdom
| | - John Svaren
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin‐MadisonMadisonUnited States
| | - Tessa Gordon
- Division of Plastic and Reconstructive Surgery, The Hospital for Sick ChildrenTorontoCanada
| | - Peter Arthur-Farraj
- John Van Geest Centre for Brain repair, Department of Clinical Neurosciences, University of CambridgeCambridgeUnited Kingdom
| | - Sergio Velasco-Aviles
- Instituto de Neurociencias de Alicante, Universidad Miguel Hernández‐CSICSan Juan de AlicanteSpain
- Hospital General Universitario de Alicante, ISABIALAlicanteSpain
| | - Hugo Cabedo
- Instituto de Neurociencias de Alicante, Universidad Miguel Hernández‐CSICSan Juan de AlicanteSpain
- Hospital General Universitario de Alicante, ISABIALAlicanteSpain
| | - Cristina Benito
- Department of Cell and Developmental Biology, University College LondonLondonUnited Kingdom
| | - Rhona Mirsky
- Department of Cell and Developmental Biology, University College LondonLondonUnited Kingdom
| | - Kristjan R Jessen
- Department of Cell and Developmental Biology, University College LondonLondonUnited Kingdom
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7
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Moreau N, Boucher Y. Hedging against Neuropathic Pain: Role of Hedgehog Signaling in Pathological Nerve Healing. Int J Mol Sci 2020; 21:ijms21239115. [PMID: 33266112 PMCID: PMC7731127 DOI: 10.3390/ijms21239115] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 11/28/2020] [Accepted: 11/29/2020] [Indexed: 12/23/2022] Open
Abstract
The peripheral nervous system has important regenerative capacities that regulate and restore peripheral nerve homeostasis. Following peripheral nerve injury, the nerve undergoes a highly regulated degeneration and regeneration process called Wallerian degeneration, where numerous cell populations interact to allow proper nerve healing. Recent studies have evidenced the prominent role of morphogenetic Hedgehog signaling pathway and its main effectors, Sonic Hedgehog (SHH) and Desert Hedgehog (DHH) in the regenerative drive following nerve injury. Furthermore, dysfunctional regeneration and/or dysfunctional Hedgehog signaling participate in the development of chronic neuropathic pain that sometimes accompanies nerve healing in the clinical context. Understanding the implications of this key signaling pathway could provide exciting new perspectives for future research on peripheral nerve healing.
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Affiliation(s)
- Nathan Moreau
- Department of Oral Medicine and Oral Surgery, Bretonneau Hospital (AP-HP), 75018 Paris, France;
- Faculty of Dental Medicine-Montrouge, University of Paris, 92120 Montrouge, France
| | - Yves Boucher
- Department of Dental Medicine, Pitié-Salpêtrière Hospital (AP-HP), 75013 Paris, France
- Faculty of Dental Medicine-Garancière, University of Paris, 75006 Paris, France
- Correspondence:
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8
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Rivera B, Nadaf J, Fahiminiya S, Apellaniz-Ruiz M, Saskin A, Chong AS, Sharma S, Wagener R, Revil T, Condello V, Harra Z, Hamel N, Sabbaghian N, Muchantef K, Thomas C, de Kock L, Hébert-Blouin MN, Bassenden AV, Rabenstein H, Mete O, Paschke R, Pusztaszeri MP, Paulus W, Berghuis A, Ragoussis J, Nikiforov YE, Siebert R, Albrecht S, Turcotte R, Hasselblatt M, Fabian MR, Foulkes WD. DGCR8 microprocessor defect characterizes familial multinodular goiter with schwannomatosis. J Clin Invest 2020; 130:1479-1490. [PMID: 31805011 DOI: 10.1172/jci130206] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 11/26/2019] [Indexed: 12/25/2022] Open
Abstract
BACKGROUNDDICER1 is the only miRNA biogenesis component associated with an inherited tumor syndrome, featuring multinodular goiter (MNG) and rare pediatric-onset lesions. Other susceptibility genes for familial forms of MNG likely exist.METHODSWhole-exome sequencing of a kindred with early-onset MNG and schwannomatosis was followed by investigation of germline pathogenic variants that fully segregated with the disease. Genome-wide analyses were performed on 13 tissue samples from familial and nonfamilial DGCR8-E518K-positive tumors, including MNG, schwannomas, papillary thyroid cancers (PTCs), and Wilms tumors. miRNA profiles of 4 tissue types were compared, and sequencing of miRNA, pre-miRNA, and mRNA was performed in a subset of 9 schwannomas, 4 of which harbor DGCR8-E518K.RESULTSWe identified c.1552G>A;p.E518K in DGCR8, a microprocessor component located in 22q, in the kindred. The variant identified is a somatic hotspot in Wilms tumors and has been identified in 2 PTCs. Copy number loss of chromosome 22q, leading to loss of heterozygosity at the DGCR8 locus, was found in all 13 samples harboring c.1552G>A;p.E518K. miRNA profiling of PTCs, MNG, schwannomas, and Wilms tumors revealed a common profile among E518K hemizygous tumors. In vitro cleavage demonstrated improper processing of pre-miRNA by DGCR8-E518K. MicroRNA and RNA profiling show that this variant disrupts precursor microRNA production, impacting populations of canonical microRNAs and mirtrons.CONCLUSIONWe identified DGCR8 as the cause of an unreported autosomal dominant mendelian tumor susceptibility syndrome: familial multinodular goiter with schwannomatosis.FUNDINGCanadian Institutes of Health Research, Compute Canada, Alex's Lemonade Stand Foundation, the Mia Neri Foundation for Childhood Cancer, Cassa di Sovvenzioni e Risparmio fra il Personale della Banca d'Italia, and the KinderKrebsInitiative Buchholz/Holm-Seppensen.
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Affiliation(s)
- Barbara Rivera
- Gerald Bronfman Department of Oncology, McGill University, Montreal, Quebec, Canada.,Lady Davis Institute for Medical Research and.,Segal Cancer Centre, Jewish General Hospital, Montreal, Quebec, Canada
| | - Javad Nadaf
- Lady Davis Institute for Medical Research and.,Segal Cancer Centre, Jewish General Hospital, Montreal, Quebec, Canada
| | - Somayyeh Fahiminiya
- Cancer Research Program, McGill University Health Centre, Montreal, Quebec, Canada
| | - Maria Apellaniz-Ruiz
- Lady Davis Institute for Medical Research and.,Segal Cancer Centre, Jewish General Hospital, Montreal, Quebec, Canada.,Cancer Research Program, McGill University Health Centre, Montreal, Quebec, Canada.,Department of Human Genetics, McGill University, Montreal, Quebec, Canada
| | - Avi Saskin
- Department of Human Genetics, McGill University, Montreal, Quebec, Canada.,Division of Medical Genetics, Department of Medicine, McGill University Health Centre and Jewish General Hospital, Montreal, Quebec, Canada
| | - Anne-Sophie Chong
- Lady Davis Institute for Medical Research and.,Segal Cancer Centre, Jewish General Hospital, Montreal, Quebec, Canada
| | - Sahil Sharma
- Department of Experimental Medicine, McGill University, Montreal, Quebec, Canada
| | - Rabea Wagener
- Institute of Human Genetics, University of Ulm and University of Ulm Medical Center, Ulm, Germany
| | - Timothée Revil
- Department of Human Genetics, McGill University, Montreal, Quebec, Canada.,Génome Québec Innovation Centre, McGill University, Montreal, Quebec, Canada
| | - Vincenzo Condello
- Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | - Zineb Harra
- Lady Davis Institute for Medical Research and.,Segal Cancer Centre, Jewish General Hospital, Montreal, Quebec, Canada
| | - Nancy Hamel
- Cancer Research Program, McGill University Health Centre, Montreal, Quebec, Canada
| | - Nelly Sabbaghian
- Lady Davis Institute for Medical Research and.,Segal Cancer Centre, Jewish General Hospital, Montreal, Quebec, Canada
| | - Karl Muchantef
- Department of Diagnostic Radiology, McGill University, Montreal, Quebec, Canada.,Pediatric Radiology, Montreal Children's Hospital, Montreal, Quebec, Canada
| | - Christian Thomas
- Institute of Neuropathology, University Hospital Muenster, Muenster, Germany
| | - Leanne de Kock
- Lady Davis Institute for Medical Research and.,Segal Cancer Centre, Jewish General Hospital, Montreal, Quebec, Canada.,Department of Human Genetics, McGill University, Montreal, Quebec, Canada
| | | | | | - Hannah Rabenstein
- Institute of Human Genetics, University of Ulm and University of Ulm Medical Center, Ulm, Germany
| | - Ozgur Mete
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada.,Department of Pathology, University Health Network, Toronto, Ontario, Canada
| | - Ralf Paschke
- Department of Medicine.,Department of Oncology.,Department of Pathology.,Biochemistry and Molecular Biology Institute, and.,Arnie Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Marc P Pusztaszeri
- Department of Pathology, Jewish General Hospital, Montreal, Quebec, Canada
| | - Werner Paulus
- Institute of Neuropathology, University Hospital Muenster, Muenster, Germany
| | - Albert Berghuis
- Department of Biochemistry, McGill University, Montreal, Quebec, Canada
| | - Jiannis Ragoussis
- Cancer Research Program, McGill University Health Centre, Montreal, Quebec, Canada.,Génome Québec Innovation Centre, McGill University, Montreal, Quebec, Canada
| | - Yuri E Nikiforov
- Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | - Reiner Siebert
- Institute of Human Genetics, University of Ulm and University of Ulm Medical Center, Ulm, Germany
| | - Steffen Albrecht
- Department of Pathology, Montreal Children's Hospital, McGill University Health Centre, Montreal, Quebec, Canada
| | - Robert Turcotte
- Division of Orthopedic Surgery (Experimental Surgery), McGill University, Montreal, Quebec, Canada.,Department of Surgical Oncology, McGill University Health Centre, Montreal, Quebec, Canada
| | - Martin Hasselblatt
- Institute of Neuropathology, University Hospital Muenster, Muenster, Germany
| | - Marc R Fabian
- Gerald Bronfman Department of Oncology, McGill University, Montreal, Quebec, Canada.,Lady Davis Institute for Medical Research and.,Segal Cancer Centre, Jewish General Hospital, Montreal, Quebec, Canada.,Department of Experimental Medicine, McGill University, Montreal, Quebec, Canada.,Department of Biochemistry, McGill University, Montreal, Quebec, Canada
| | - William D Foulkes
- Gerald Bronfman Department of Oncology, McGill University, Montreal, Quebec, Canada.,Lady Davis Institute for Medical Research and.,Segal Cancer Centre, Jewish General Hospital, Montreal, Quebec, Canada.,Cancer Research Program, McGill University Health Centre, Montreal, Quebec, Canada.,Department of Human Genetics, McGill University, Montreal, Quebec, Canada.,Division of Medical Genetics, Department of Medicine, McGill University Health Centre and Jewish General Hospital, Montreal, Quebec, Canada
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9
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Milichko V, Dyachuk V. Novel Glial Cell Functions: Extensive Potency, Stem Cell-Like Properties, and Participation in Regeneration and Transdifferentiation. Front Cell Dev Biol 2020; 8:809. [PMID: 33015034 PMCID: PMC7461986 DOI: 10.3389/fcell.2020.00809] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Accepted: 07/31/2020] [Indexed: 12/26/2022] Open
Abstract
Glial cells are the most abundant cells in both the peripheral and central nervous systems. During the past decade, a subpopulation of immature peripheral glial cells, namely, embryonic Schwann cell-precursors, have been found to perform important functions related to development. These cells have properties resembling those of the neural crest and, depending on their location in the body, can transform into several different cell types in peripheral tissues, including autonomic neurons. This review describes the multipotent properties of Schwann cell-precursors and their importance, together with innervation, during early development. The heterogeneity of Schwann cells, as revealed using single-cell transcriptomics, raises a question on whether some glial cells in the adult peripheral nervous system retain their stem cell-like properties. We also discuss how a deeper insight into the biology of both embryonic and adult Schwann cells might lead to an effective treatment of the damage of both neural and non-neural tissues, including the damage caused by neurodegenerative diseases. Furthermore, understanding the potential involvement of Schwann cells in the regulation of tumor development may reveal novel targets for cancer treatment.
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Affiliation(s)
- Valentin Milichko
- Department of Nanophotonics and Metamaterials, ITMO University, St. Petersburg, Russia
| | - Vyacheslav Dyachuk
- Department of Nanophotonics and Metamaterials, ITMO University, St. Petersburg, Russia.,National Scientific Center of Marine Biology, Far Eastern Branch, Russian Academy of Sciences, Vladivostok, Russia
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10
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Gacem N, Kavo A, Zerad L, Richard L, Mathis S, Kapur RP, Parisot M, Amiel J, Dufour S, de la Grange P, Pingault V, Vallat JM, Bondurand N. ADAR1 mediated regulation of neural crest derived melanocytes and Schwann cell development. Nat Commun 2020; 11:198. [PMID: 31924792 PMCID: PMC6954203 DOI: 10.1038/s41467-019-14090-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Accepted: 12/09/2019] [Indexed: 01/14/2023] Open
Abstract
The neural crest gives rise to numerous cell types, dysfunction of which contributes to many disorders. Here, we report that adenosine deaminase acting on RNA (ADAR1), responsible for adenosine-to-inosine editing of RNA, is required for regulating the development of two neural crest derivatives: melanocytes and Schwann cells. Neural crest specific conditional deletion of Adar1 in mice leads to global depigmentation and absence of myelin from peripheral nerves, resulting from alterations in melanocyte survival and differentiation of Schwann cells, respectively. Upregulation of interferon stimulated genes precedes these defects, which are associated with the triggering of a signature resembling response to injury in peripheral nerves. Simultaneous extinction of MDA5, a key sensor of unedited RNA, rescues both melanocytes and myelin defects in vitro, suggesting that ADAR1 safeguards neural crest derivatives from aberrant MDA5-mediated interferon production. We thus extend the landscape of ADAR1 function to the fields of neural crest development and disease.
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Affiliation(s)
- Nadjet Gacem
- Laboratory of Embryology and Genetics of Human Malformation, Imagine Institute, INSERM UMR 1163, Universite Paris Descartes-Universite de Paris, Paris, France.,INSERM, U955, Equipe 06, 8, rue du General Sarrail, 94010, Creteil Cedex, France
| | - Anthula Kavo
- INSERM, U955, Equipe 06, 8, rue du General Sarrail, 94010, Creteil Cedex, France.,Faculte de Medecine, Universite Paris Est, 94000, Creteil, France
| | - Lisa Zerad
- Laboratory of Embryology and Genetics of Human Malformation, Imagine Institute, INSERM UMR 1163, Universite Paris Descartes-Universite de Paris, Paris, France
| | - Laurence Richard
- Department of Neurology, Centre de Reference Neuropathies Peripheriques Rares, 2 avenue Martin-Luther-King, 87042, Limoges, France
| | - Stephane Mathis
- Department of Neurology (Nerve-Muscle Unit) and Grand Sud-Ouest National Reference Center for Neuromuscular Disorders, CHU Bordeaux, Pellegrin Hospital, 33076, Bordeaux, France
| | - Raj P Kapur
- Department of Pathology, Seattle Children's Hospital and University of Washington, 4800 Sand Point Way NE, Seattle, WA, 98105, USA
| | - Melanie Parisot
- Genomics Core Facility, Institut Imagine-Structure Federative de Recherche Necker, INSERM U1163 and INSERM US24/CNRS UMS3633, 24 bvd Montparnasse, 75015, Paris, France
| | - Jeanne Amiel
- Laboratory of Embryology and Genetics of Human Malformation, Imagine Institute, INSERM UMR 1163, Universite Paris Descartes-Universite de Paris, Paris, France
| | - Sylvie Dufour
- INSERM, U955, Equipe 06, 8, rue du General Sarrail, 94010, Creteil Cedex, France.,Faculte de Medecine, Universite Paris Est, 94000, Creteil, France
| | | | - Veronique Pingault
- Laboratory of Embryology and Genetics of Human Malformation, Imagine Institute, INSERM UMR 1163, Universite Paris Descartes-Universite de Paris, Paris, France.,Service de Genetique Moleculaire, Hopital Necker-Enfants-Malades, 149 rue de Sevres, 75015, Paris, France
| | - Jean Michel Vallat
- Department of Neurology, Centre de Reference Neuropathies Peripheriques Rares, 2 avenue Martin-Luther-King, 87042, Limoges, France
| | - Nadege Bondurand
- Laboratory of Embryology and Genetics of Human Malformation, Imagine Institute, INSERM UMR 1163, Universite Paris Descartes-Universite de Paris, Paris, France. .,INSERM, U955, Equipe 06, 8, rue du General Sarrail, 94010, Creteil Cedex, France.
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11
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Motahari Z, Moody SA, Maynard TM, LaMantia AS. In the line-up: deleted genes associated with DiGeorge/22q11.2 deletion syndrome: are they all suspects? J Neurodev Disord 2019; 11:7. [PMID: 31174463 PMCID: PMC6554986 DOI: 10.1186/s11689-019-9267-z] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Accepted: 04/21/2019] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND 22q11.2 deletion syndrome (22q11DS), a copy number variation (CNV) disorder, occurs in approximately 1:4000 live births due to a heterozygous microdeletion at position 11.2 (proximal) on the q arm of human chromosome 22 (hChr22) (McDonald-McGinn and Sullivan, Medicine 90:1-18, 2011). This disorder was known as DiGeorge syndrome, Velo-cardio-facial syndrome (VCFS) or conotruncal anomaly face syndrome (CTAF) based upon diagnostic cardiovascular, pharyngeal, and craniofacial anomalies (McDonald-McGinn and Sullivan, Medicine 90:1-18, 2011; Burn et al., J Med Genet 30:822-4, 1993) before this phenotypic spectrum was associated with 22q11.2 CNVs. Subsequently, 22q11.2 deletion emerged as a major genomic lesion associated with vulnerability for several clinically defined behavioral deficits common to a number of neurodevelopmental disorders (Fernandez et al., Principles of Developmental Genetics, 2015; Robin and Shprintzen, J Pediatr 147:90-6, 2005; Schneider et al., Am J Psychiatry 171:627-39, 2014). RESULTS The mechanistic relationships between heterozygously deleted 22q11.2 genes and 22q11DS phenotypes are still unknown. We assembled a comprehensive "line-up" of the 36 protein coding loci in the 1.5 Mb minimal critical deleted region on hChr22q11.2, plus 20 protein coding loci in the distal 1.5 Mb that defines the 3 Mb typical 22q11DS deletion. We categorized candidates based upon apparent primary cell biological functions. We analyzed 41 of these genes that encode known proteins to determine whether haploinsufficiency of any single 22q11.2 gene-a one gene to one phenotype correspondence due to heterozygous deletion restricted to that locus-versus complex multigenic interactions can account for single or multiple 22q11DS phenotypes. CONCLUSIONS Our 22q11.2 functional genomic assessment does not support current theories of single gene haploinsufficiency for one or all 22q11DS phenotypes. Shared molecular functions, convergence on fundamental cell biological processes, and related consequences of individual 22q11.2 genes point to a matrix of multigenic interactions due to diminished 22q11.2 gene dosage. These interactions target fundamental cellular mechanisms essential for development, maturation, or homeostasis at subsets of 22q11DS phenotypic sites.
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Affiliation(s)
- Zahra Motahari
- The Institute for Neuroscience, and Department of Anatomy and Cell Biology, The George Washington University School of Medicine and Health Sciences, Washington DC, 20037 USA
| | - Sally Ann Moody
- The Institute for Neuroscience, and Department of Anatomy and Cell Biology, The George Washington University School of Medicine and Health Sciences, Washington DC, 20037 USA
| | - Thomas Michael Maynard
- The Institute for Neuroscience, and Department of Anatomy and Cell Biology, The George Washington University School of Medicine and Health Sciences, Washington DC, 20037 USA
| | - Anthony-Samuel LaMantia
- The Institute for Neuroscience, and Department of Anatomy and Cell Biology, The George Washington University School of Medicine and Health Sciences, Washington DC, 20037 USA
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12
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Guo WT, Wang Y. Dgcr8 knockout approaches to understand microRNA functions in vitro and in vivo. Cell Mol Life Sci 2019; 76:1697-1711. [PMID: 30694346 PMCID: PMC11105204 DOI: 10.1007/s00018-019-03020-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 01/11/2019] [Accepted: 01/17/2019] [Indexed: 01/07/2023]
Abstract
Biologic function of the majority of microRNAs (miRNAs) is still unknown. Uncovering the function of miRNAs is hurdled by redundancy among different miRNAs. The deletion of Dgcr8 leads to the deficiency in producing all canonical miRNAs, therefore, overcoming the redundancy issue. Dgcr8 knockout strategy has been instrumental in understanding the function of miRNAs in a variety of cells in vitro and in vivo. In this review, we will first give a brief introduction about miRNAs, miRNA biogenesis pathway and the role of Dgcr8 in miRNA biogenesis. We will then summarize studies performed with Dgcr8 knockout cell models with a focus on embryonic stem cells. After that, we will summarize results from various in vivo Dgcr8 knockout models. Given significant phenotypic differences in various tissues between Dgcr8 and Dicer knockout, we will also briefly review current progresses on understanding miRNA-independent functions of miRNA biogenesis factors. Finally, we will discuss the potential use of a new strategy to stably express miRNAs in Dgcr8 knockout cells. In future, Dgcr8 knockout approaches coupled with innovations in miRNA rescue strategy may provide further insights into miRNA functions in vitro and in vivo.
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Affiliation(s)
- Wen-Ting Guo
- Central Laboratory, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, No. 1 Shuaifuyuan, Beijing, 100730, People's Republic of China
| | - Yangming Wang
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, Peking University, Beijing, 100871, People's Republic of China.
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13
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Jessen KR, Arthur-Farraj P. Repair Schwann cell update: Adaptive reprogramming, EMT, and stemness in regenerating nerves. Glia 2019; 67:421-437. [PMID: 30632639 DOI: 10.1002/glia.23532] [Citation(s) in RCA: 199] [Impact Index Per Article: 39.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 08/20/2018] [Accepted: 09/05/2018] [Indexed: 12/16/2022]
Abstract
Schwann cells respond to nerve injury by cellular reprogramming that generates cells specialized for promoting regeneration and repair. These repair cells clear redundant myelin, attract macrophages, support survival of damaged neurons, encourage axonal growth, and guide axons back to their targets. There are interesting parallels between this response and that found in other tissues. At the cellular level, many other tissues also react to injury by cellular reprogramming, generating cells specialized to promote tissue homeostasis and repair. And at the molecular level, a common feature possessed by Schwann cells and many other cells is the injury-induced activation of genes associated with epithelial-mesenchymal transitions and stemness, differentiation states that are linked to cellular plasticity and that help injury-induced tissue remodeling. The number of signaling systems regulating Schwann cell plasticity is rapidly increasing. Importantly, this includes mechanisms that are crucial for the generation of functional repair Schwann cells and nerve regeneration, although they have no or a minor role elsewhere in the Schwann cell lineage. This encourages the view that selective tools can be developed to control these particular cells, amplify their repair supportive functions and prevent their deterioration. In this review, we discuss the emerging similarities between the injury response seen in nerves and in other tissues and survey the transcription factors, epigenetic mechanisms, and signaling cascades that control repair Schwann cells, with emphasis on systems that selectively regulate the Schwann cell injury response.
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Affiliation(s)
- Kristjan R Jessen
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Peter Arthur-Farraj
- John Van Geest Centre for Brain Repair, Department of Clinical Neurosciences, University of Cambridge, Cambridge, United Kingdom
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14
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Jessen KR, Mirsky R. The Success and Failure of the Schwann Cell Response to Nerve Injury. Front Cell Neurosci 2019; 13:33. [PMID: 30804758 PMCID: PMC6378273 DOI: 10.3389/fncel.2019.00033] [Citation(s) in RCA: 259] [Impact Index Per Article: 51.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Accepted: 01/22/2019] [Indexed: 01/06/2023] Open
Abstract
The remarkable plasticity of Schwann cells allows them to adopt the Remak (non-myelin) and myelin phenotypes, which are specialized to meet the needs of small and large diameter axons, and differ markedly from each other. It also enables Schwann cells initially to mount a strikingly adaptive response to nerve injury and to promote regeneration by converting to a repair-promoting phenotype. These repair cells activate a sequence of supportive functions that engineer myelin clearance, prevent neuronal death, and help axon growth and guidance. Eventually, this response runs out of steam, however, because in the long run the phenotype of repair cells is unstable and their survival is compromised. The re-programming of Remak and myelin cells to repair cells, together with the injury-induced switch of peripheral neurons to a growth mode, gives peripheral nerves their strong regenerative potential. But it remains a challenge to harness this potential and devise effective treatments that maintain the initial repair capacity of peripheral nerves for the extended periods typically required for nerve repair in humans.
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Affiliation(s)
- Kristjan R Jessen
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Rhona Mirsky
- Department of Cell and Developmental Biology, University College London, London, United Kingdom
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15
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Gökbuget D, Pereira JA, Opitz L, Christe D, Kessler T, Marchais A, Suter U. The miRNA biogenesis pathway prevents inappropriate expression of injury response genes in developing and adult Schwann cells. Glia 2018; 66:2632-2644. [PMID: 30295958 PMCID: PMC6585637 DOI: 10.1002/glia.23516] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 07/18/2018] [Accepted: 07/18/2018] [Indexed: 12/24/2022]
Abstract
Proper function of the nervous system depends on myelination. In peripheral nerves, Schwann cells (SCs) myelinate axons and the miRNA biogenesis pathway is required for developmental myelination and myelin maintenance. However, regulatory roles of this pathway at different stages of myelination are only partially understood. We addressed the requirement of the core miRNA biogenesis pathway components Dgcr8, Drosha, and Dicer in developing and adult SCs using mouse mutants with a comparative genetics and transcriptomics approach. We found that the microprocessor components Dgcr8 and Drosha are crucial for axonal radial sorting and to establish correct SC numbers upon myelination. Transcriptome analyses revealed a requirement of the microprocessor to prevent aberrantly increased expression of injury-response genes. Those genes are predicted targets of abundant miRNAs in sciatic nerves (SNs) during developmental myelination. In agreement, Dgcr8 and Dicer are required for proper maintenance of the myelinated SC state, where abundant miRNAs in adult SNs are predicted to target injury-response genes. We conclude that the miRNA biogenesis pathway in SCs is crucial for preventing inappropriate activity of injury-response genes in developing and adult SCs.
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Affiliation(s)
- Deniz Gökbuget
- ETH Zurich, Department of BiologyInstitute of Molecular Health SciencesZurichSwitzerland
| | - Jorge A. Pereira
- ETH Zurich, Department of BiologyInstitute of Molecular Health SciencesZurichSwitzerland
| | - Lennart Opitz
- ETH Zurich/University of ZurichFunctional Genomics Center ZurichZurichSwitzerland
| | - Dominik Christe
- ETH Zurich, Department of BiologyInstitute of Molecular Health SciencesZurichSwitzerland
| | - Tobias Kessler
- ETH Zurich, Department of BiologyInstitute of Molecular Health SciencesZurichSwitzerland
| | - Antonin Marchais
- ETH Zurich, Department of BiologyInstitute of Agricultural SciencesZurichSwitzerland
| | - Ueli Suter
- ETH Zurich, Department of BiologyInstitute of Molecular Health SciencesZurichSwitzerland
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16
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Ma KH, Duong P, Moran JJ, Junaidi N, Svaren J. Polycomb repression regulates Schwann cell proliferation and axon regeneration after nerve injury. Glia 2018; 66:2487-2502. [PMID: 30306639 PMCID: PMC6289291 DOI: 10.1002/glia.23500] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 07/02/2018] [Accepted: 07/03/2018] [Indexed: 01/01/2023]
Abstract
The transition of differentiated Schwann cells to support of nerve repair after injury is accompanied by remodeling of the Schwann cell epigenome. The EED-containing polycomb repressive complex 2 (PRC2) catalyzes histone H3K27 methylation and represses key nerve repair genes such as Shh, Gdnf, and Bdnf, and their activation is accompanied by loss of H3K27 methylation. Analysis of nerve injury in mice with a Schwann cell-specific loss of EED showed the reversal of polycomb repression is required and a rate limiting step in the increased transcription of Neuregulin 1 (type I), which is required for efficient remyelination. However, mouse nerves with EED-deficient Schwann cells display slow axonal regeneration with significantly low expression of axon guidance genes, including Sema4f and Cntf. Finally, EED loss causes impaired Schwann cell proliferation after injury with significant induction of the Cdkn2a cell cycle inhibitor gene. Interestingly, PRC2 subunits and CDKN2A are commonly co-mutated in the transition from benign neurofibromas to malignant peripheral nerve sheath tumors (MPNST's). RNA-seq analysis of EED-deficient mice identified PRC2-regulated molecular pathways that may contribute to the transition to malignancy in neurofibromatosis.
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Affiliation(s)
- Ki H. Ma
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Phu Duong
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
- Cellular and Molecular Pathology Graduate Program, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - John J. Moran
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Nabil Junaidi
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - John Svaren
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
- Department of Comparative Biosciences, University of Wisconsin-Madison, Madison, WI 53705, USA
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17
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Weiner AMJ. MicroRNAs and the neural crest: From induction to differentiation. Mech Dev 2018; 154:98-106. [PMID: 29859253 DOI: 10.1016/j.mod.2018.05.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 05/18/2018] [Accepted: 05/28/2018] [Indexed: 01/06/2023]
Abstract
MicroRNAs are small noncoding RNAs that can control gene expression by base pairing to partially complementary mRNAs. Regulation by microRNAs plays essential roles in diverse biological processes such as neural crest formation during embryonic development. The neural crest is a multipotent cell population that develops from the dorsal neural fold of vertebrate embryos in order to migrate extensively and differentiate into a variety of tissues. Gene regulatory networks that coordinate neural crest cell specification and differentiation have been considerably studied so far. Although it is known that microRNAs play important roles in neural crest development, posttranscriptional regulation by microRNAs has not been deeply characterized yet. This review is focused on the microRNAs identified so far in order to regulate gene expression of neural crest cells during vertebrate development.
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Affiliation(s)
- Andrea M J Weiner
- Instituto de Biología Molecular y Celular de Rosario (IBR), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario (UNR), Ocampo y Esmeralda, S2000EZP Rosario, Argentina.
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18
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Lin HP, Oksuz I, Svaren J, Awatramani R. Egr2-dependent microRNA-138 is dispensable for peripheral nerve myelination. Sci Rep 2018; 8:3817. [PMID: 29491350 PMCID: PMC5830491 DOI: 10.1038/s41598-018-22010-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 02/14/2018] [Indexed: 12/27/2022] Open
Abstract
Recent studies have elucidated the crucial role for microRNAs in peripheral nerve myelination by ablating components of the microRNA synthesis machinery. Few studies have focused on the role of individual microRNAs. To fill this gap, we focused this study on miR-138, which was shown to be drastically reduced in Dicer1 and Dgcr8 knockout mice with hypomyelinating phenotypes and to potentially target the negative regulators of Schwann cell differentiation. Here, we show that of two miR-138 encoding loci, mir-138-1 is the predominant locus transcribed in Schwann cells. mir-138-1 is transcriptionally upregulated during myelination and downregulated upon nerve injury. EGR2 is required for mir-138-1 transcription during development, and both SOX10 and EGR2 bind to an active enhancer near the mir-138-1 locus. Based on expression analyses, we hypothesized that miR-138 facilitates the transition between undifferentiated Schwann cells and myelinating Schwann cells. However, in conditional knockouts, we could not detect significant changes in Schwann cell proliferation, cell cycle exit, or myelination. Overall, our results demonstrate that miR-138 is an Egr2-dependent microRNA but is dispensable for Schwann cell myelination.
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Affiliation(s)
- Hsin-Pin Lin
- Department of Neurology and Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA
| | - Idil Oksuz
- Department of Neurology and Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA
| | - John Svaren
- Waisman Center and Department of Comparative Biosciences, University of Wisconsin-Madison, Madison, WI, 53705, USA
| | - Rajeshwar Awatramani
- Department of Neurology and Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA.
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19
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Abstract
The journey of Schwann cells from their origin in the neural crest to their ensheathment and myelination of peripheral nerves is a remarkable one. Their apparent static function in enabling saltatory conduction of mature nerve is not only vital for long-term health of peripheral nerve but also belies an innate capacity of terminally differentiated Schwann cells to radically alter their differentiation status in the face of nerve injury. The transition from migrating neural crest cells to nerve ensheathment, and then myelination of large diameter axons has been characterized extensively and several of the transcriptional networks have been identified. However, transcription factors must also modify chromatin structure during Schwann cell maturation and this review will focus on chromatin modification machinery that is involved in promoting the transition to, and maintenance of, myelinating Schwann cells. In addition, Schwann cells are known to play important regenerative roles after peripheral nerve injury, and information on epigenomic reprogramming of the Schwann cell genome has emerged. Characterization of epigenomic requirements for myelin maintenance and Schwann cell responses to injury will be vital in understanding how the various Schwann cell functions can be optimized to maintain and repair peripheral nerve function.
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Affiliation(s)
- Ki H Ma
- 1 Waisman Center, University of Wisconsin-Madison, Madison, WI, USA
| | - John Svaren
- 1 Waisman Center, University of Wisconsin-Madison, Madison, WI, USA.,2 Department of Comparative Biosciences, University of Wisconsin-Madison, Madison, WI, USA
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20
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Wang XW, Hao J, Guo WT, Liao LQ, Huang SY, Guo X, Bao X, Esteban MA, Wang Y. A DGCR8-Independent Stable MicroRNA Expression Strategy Reveals Important Functions of miR-290 and miR-183-182 Families in Mouse Embryonic Stem Cells. Stem Cell Reports 2017; 9:1618-1629. [PMID: 28988987 PMCID: PMC5830984 DOI: 10.1016/j.stemcr.2017.08.027] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 08/30/2017] [Accepted: 08/31/2017] [Indexed: 12/21/2022] Open
Abstract
Dgcr8 knockout cells provide a great means to understand the function of microRNAs (miRNAs) in vitro and in vivo. Current strategies to study miRNA function in Dgcr8 knockout cells depend on transient transfection of chemically synthesized miRNA mimics, which is costly and not suitable for long-term study and genetic selection of miRNA function. Here, we developed a cost-effective DGCR8-independent stable miRNA expression (DISME) strategy based on a short hairpin RNA vector that can be precisely processed by DICER. Using DISME, we found that miR-294 promoted the formation of meso-endoderm lineages during embryonic stem cell differentiation. Furthermore, DISME allowed for a pooled screen of miRNA function and identified an miR-183-182 cluster of miRNAs promoting self-renewal and pluripotency in mouse embryonic stem cells. Altogether, our study demonstrates that DISME is a robust and cost-effective strategy that allows for long-term study and genetic selection of miRNA function in a Dgcr8 knockout background.
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Affiliation(s)
- Xi-Wen Wang
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, Peking University, Beijing 100871, China
| | - Jing Hao
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, Peking University, Beijing 100871, China
| | - Wen-Ting Guo
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, Peking University, Beijing 100871, China
| | - Le-Qi Liao
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, Peking University, Beijing 100871, China
| | - Si-Yue Huang
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, Peking University, Beijing 100871, China
| | - Xiangpeng Guo
- Laboratory of RNA, Chromatin, and Human Disease, Key Laboratory of Regenerative Biology and Guangdong Provincial Key Laboratory of Stem Cells and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China
| | - Xichen Bao
- Laboratory of RNA, Chromatin, and Human Disease, Key Laboratory of Regenerative Biology and Guangdong Provincial Key Laboratory of Stem Cells and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China
| | - Miguel A Esteban
- Laboratory of RNA, Chromatin, and Human Disease, Key Laboratory of Regenerative Biology and Guangdong Provincial Key Laboratory of Stem Cells and Regenerative Medicine, Guangzhou Institutes of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, China
| | - Yangming Wang
- Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, Peking University, Beijing 100871, China.
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21
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Comparison of DNA Methylation in Schwann Cells before and after Peripheral Nerve Injury in Rats. BIOMED RESEARCH INTERNATIONAL 2017; 2017:5393268. [PMID: 28459064 PMCID: PMC5385226 DOI: 10.1155/2017/5393268] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 02/23/2017] [Accepted: 03/08/2017] [Indexed: 01/13/2023]
Abstract
This study aims to find the difference of genomewide DNA methylation in Schwann cells (SCs) before and after peripheral nerve system (PNS) injury by Methylated DNA Immunoprecipitation Sequencing (MeDIP-Seq) and seek meaningful differentially methylated genes related to repairment of injured PNS. SCs harvested from sciatic nerve were named as activated Schwann cells (ASCs), and the ones harvested from brachial plexus were named as normal Schwann cells (NSCs). Genomic DNA of ASCs and NSCs were isolated and MeDIP-Seq was conducted. Differentially methylated genes and regions were discovered and analyzed by bioinformatic methods. MeDIP-Seq analysis showed methylation differences were identified between ASCs and NSCs. The distribution of differentially methylated regions (DMRs) peaks in different components of genome was mainly located in distal intergenic regions. GO and KEGG analysis of these methylated genes were also conducted. The expression patterns of hypermethylated genes (Dgcr8, Zeb2, Dixdc1, Sox2, and Shh) and hypomethylated genes (Gpr126, Birc2) detected by qRT-PCR were opposite to the MeDIP analysis data with significance (p < 0.05), which proved MeDIP analysis data were real and believable. Our data serve as a basis for understanding the injury-induced epigenetic changes in SCs and the foundation for further studies on repair of PNS injury.
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22
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Ma KH, Hung HA, Svaren J. Epigenomic Regulation of Schwann Cell Reprogramming in Peripheral Nerve Injury. J Neurosci 2016; 36:9135-47. [PMID: 27581455 PMCID: PMC5005723 DOI: 10.1523/jneurosci.1370-16.2016] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Revised: 07/08/2016] [Accepted: 07/15/2016] [Indexed: 12/16/2022] Open
Abstract
UNLABELLED The rapid and dynamic transcriptional changes of Schwann cells in response to injury are critical to peripheral nerve repair, yet the epigenomic reprograming that leads to the induction of injury-activated genes has not been characterized. Polycomb Repressive Complex 2 (PRC2) catalyzes the trimethylation of lysine 27 of histone H3 (H3K27me3), which produces a transcriptionally repressive chromatin environment. We find that many promoters and/or gene bodies of injury-activated genes of mature rat nerves are occupied with H3K27me3. In contrast, the majority of distal enhancers that gain H3K27 acetylation after injury are not repressed by H3K27 methylation before injury, which is normally observed in developmentally poised enhancers. Injury induces demethylation of H3K27 in many genes, such as Sonic hedgehog (Shh), which is silenced throughout Schwann cell development before injury. In addition, experiments using a Schwann cell-specific mouse knock-out of the Eed subunit of PRC2 indicate that demethylation is a rate-limiting step in the activation of such genes. We also show that some transcription start sites of H3K27me3-repressed injury genes of uninjured nerves are bound with a mark of active promoters H3K4me3, for example, Shh and Gdnf, and the reduction of H3K27me3 results in increased trimethylation of H3K4. Our findings identify reversal of polycomb repression as a key step in gene activation after injury. SIGNIFICANCE STATEMENT Peripheral nerve regeneration after injury is dependent upon implementation of a novel genetic program in Schwann cells that supports axonal survival and regeneration. Identifying means to enhance Schwann cell reprogramming after nerve injury could be used to foster effective remyelination in the treatment of demyelinating disorders and in identifying pathways involved in regenerative process of myelination. Although recent progress has identified transcriptional determinants of successful reprogramming of the Schwann cell transcriptome after nerve injury, our results have highlighted a novel epigenomic pathway in which reversal of the Polycomb pathway of repressive histone methylation is required for activation of a significant number of injury-induced genes.
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Affiliation(s)
- Ki H Ma
- Waisman Center, Cellular and Molecular Pathology Graduate Program, and
| | - Holly A Hung
- Waisman Center, Cellular and Molecular Pathology Graduate Program, and
| | - John Svaren
- Waisman Center, Department of Comparative Biosciences, University of Wisconsin, Madison, Wisconsin 53705
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Luoni A, Riva MA. MicroRNAs and psychiatric disorders: From aetiology to treatment. Pharmacol Ther 2016; 167:13-27. [PMID: 27452338 DOI: 10.1016/j.pharmthera.2016.07.006] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 07/14/2016] [Indexed: 01/09/2023]
Abstract
The emergence of psychiatric disorders relies on the interaction between genetic vulnerability and environmental adversities. Several studies have demonstrated a crucial role for epigenetics (e.g. DNA methylation, post-translational histone modifications and microRNA-mediated post-transcriptional regulation) in the translation of environmental cues into adult behavioural outcome, which can prove to be harmful thus increasing the risk to develop psychopathology. Within this frame, non-coding RNAs, especially microRNAs, came to light as pivotal regulators of many biological processes occurring in the Central Nervous System, both during the neuronal development as well as in the regulation of adult function, including learning, memory and neuronal plasticity. On these basis, in recent years it has been hypothesised a central role for microRNA modulation and expression regulation in many brain disorders, including neurodegenerative disorders and mental illnesses. Indeed, the aim of the present review is to present the most recent state of the art regarding microRNA involvement in psychiatric disorders. We will first describe the mechanisms that regulate microRNA biogenesis and we will report evidences of microRNA dysregulation in peripheral body fluids, in postmortem brain tissues from patients suffering from psychopathology as well as in animal models. Last, we will discuss the potential to consider microRNAs as putative target for pharmacological intervention, using common psychotropic drugs or more specific tools, with the aim to normalize functions that are disrupted in different psychiatric conditions.
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Affiliation(s)
- Alessia Luoni
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Via Balzaretti 9, 20133 Milan, Italy
| | - Marco Andrea Riva
- Department of Pharmacological and Biomolecular Sciences, Università degli Studi di Milano, Via Balzaretti 9, 20133 Milan, Italy.
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Caronia-Brown G, Anderegg A, Awatramani R. Expression and functional analysis of the Wnt/beta-catenin induced mir-135a-2 locus in embryonic forebrain development. Neural Dev 2016; 11:9. [PMID: 27048518 PMCID: PMC4822265 DOI: 10.1186/s13064-016-0065-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 04/01/2016] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Brain size and patterning are dependent on dosage-sensitive morphogen signaling pathways - yet how these pathways are calibrated remains enigmatic. Recent studies point to a new role for microRNAs in tempering the spatio-temporal range of morphogen functions during development. Here, we investigated the role of miR-135a, derived from the mir-135a-2 locus, in embryonic forebrain development. METHOD 1. We characterized the expression of miR-135a, and its host gene Rmst, by in situ hybridization (ish). 2. We conditionally ablated, or activated, beta-catenin in the dorsal forebrain to determine if this pathway was necessary and/or sufficient for Rmst/miR-135a expression. 3. We performed bioinformatics analysis to unveil the most predicted pathways targeted by miR-135a. 4. We performed gain and loss of function experiments on mir-135a-2 and analyzed by ish the expression of key markers of cortical hem, choroid plexus, neocortex and hippocampus. RESULTS 1. miR-135a, embedded in the host long non-coding transcript Rmst, is robustly expressed, and functional, in the medial wall of the embryonic dorsal forebrain, a Wnt and TGFβ/BMP-rich domain. 2. Canonical Wnt/beta-catenin signaling is critical for the expression of Rmst and miR-135a, and the cortical hem determinant Lmx1a. 3. Bioinformatics analyses reveal that the Wnt and TGFβ/BMP cascades are among the top predicted pathways targeted by miR-135a. 4. Analysis of mir-135a-2 null embryos showed that dorsal forebrain development appeared normal. In contrast, modest mir-135a-2 overexpression, in the early dorsal forebrain, resulted in a phenotype resembling that of mutants with Wnt and TGFβ/BMP deficits - a smaller cortical hem and hippocampus primordium associated with a shorter neocortex as well as a less convoluted choroid plexus. Interestingly, late overexpression of mir-135a-2 revealed no change. CONCLUSIONS All together, our data suggests the existence of a Wnt/miR-135a auto-regulatory loop, which could serve to limit the extent, the duration and/or intensity of the Wnt and, possibly, the TGFβ/BMP pathways.
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Affiliation(s)
- Giuliana Caronia-Brown
- Department of Neurology and Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, 7-113 Lurie Bldg., 303 E. Superior Street, Chicago, IL, 60611, USA.
| | - Angela Anderegg
- Department of Neurology and Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, 7-113 Lurie Bldg., 303 E. Superior Street, Chicago, IL, 60611, USA
| | - Rajeshwar Awatramani
- Department of Neurology and Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, 7-113 Lurie Bldg., 303 E. Superior Street, Chicago, IL, 60611, USA
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Jessen KR, Mirsky R. The repair Schwann cell and its function in regenerating nerves. J Physiol 2016; 594:3521-31. [PMID: 26864683 PMCID: PMC4929314 DOI: 10.1113/jp270874] [Citation(s) in RCA: 711] [Impact Index Per Article: 88.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 11/28/2015] [Indexed: 01/05/2023] Open
Abstract
Nerve injury triggers the conversion of myelin and non‐myelin (Remak) Schwann cells to a cell phenotype specialized to promote repair. Distal to damage, these repair Schwann cells provide the necessary signals and spatial cues for the survival of injured neurons, axonal regeneration and target reinnervation. The conversion to repair Schwann cells involves de‐differentiation together with alternative differentiation, or activation, a combination that is typical of cell type conversions often referred to as (direct or lineage) reprogramming. Thus, injury‐induced Schwann cell reprogramming involves down‐regulation of myelin genes combined with activation of a set of repair‐supportive features, including up‐regulation of trophic factors, elevation of cytokines as part of the innate immune response, myelin clearance by activation of myelin autophagy in Schwann cells and macrophage recruitment, and the formation of regeneration tracks, Bungner's bands, for directing axons to their targets. This repair programme is controlled transcriptionally by mechanisms involving the transcription factor c‐Jun, which is rapidly up‐regulated in Schwann cells after injury. In the absence of c‐Jun, damage results in the formation of a dysfunctional repair cell, neuronal death and failure of functional recovery. c‐Jun, although not required for Schwann cell development, is therefore central to the reprogramming of myelin and non‐myelin (Remak) Schwann cells to repair cells after injury. In future, the signalling that specifies this cell requires further analysis so that pharmacological tools that boost and maintain the repair Schwann cell phenotype can be developed.
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Affiliation(s)
- K R Jessen
- Department of Cell and Developmental Biology, University College London, Gower Street, London, WC1E 6BT, UK
| | - R Mirsky
- Department of Cell and Developmental Biology, University College London, Gower Street, London, WC1E 6BT, UK
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Affiliation(s)
- Ki H Ma
- Waisman Center, University of Wisconsin-Madison, Madison, WI, USA; Cellular and Molecular Pathology Graduate Program, University of Wisconsin-Madison, Madison, WI, USA
| | - John Svaren
- Waisman Center, University of Wisconsin-Madison, Madison, WI, USA; Cellular and Molecular Pathology Graduate Program, University of Wisconsin-Madison, Madison, WI, USA; Department of Comparative Biosciences, University of Wisconsin-Madison, Madison, WI, USA
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