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Chen CH, Chen Y, Li YN, Zhang H, Huang X, Li YY, Li ZY, Han JX, Wu XY, Liu HJ, Sun T. EGR3 Inhibits Tumor Progression by Inducing Schwann Cell-Like Differentiation. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2400066. [PMID: 38973154 PMCID: PMC11425834 DOI: 10.1002/advs.202400066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 05/31/2024] [Indexed: 07/09/2024]
Abstract
The mechanism and function of the expression of Schwann characteristics by nevus cells in the mature zone of the dermis are unknown. Early growth response 3 (EGR3) induces Schwann cell-like differentiation of melanoma cells by simulating the process of nevus maturation, which leads to a strong phenotypic transformation of the cells, including the formation of long protrusions and a decrease in cell motility, proliferation, and melanin production. Meanwhile, EGR3 regulates the levels of myelin protein zero (MPZ) and collagen type I alpha 1 chain (COL1A1) through SRY-box transcription factor 10 (SOX10)-dependent and independent mechanisms, by binding to non-strictly conserved motifs, respectively. Schwann cell-like differentiation demonstrates significant benefits in both in vivo and clinical studies. Finally, a CD86-P2A-EGR3 recombinant mRNA vaccine is developed which leads to tumor control through forced cell differentiation and enhanced immune infiltration. Together, these data support further development of the recombinant mRNA as a treatment for cancer.
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Affiliation(s)
- Cai-Hong Chen
- Tianjin Nankai University State Key Laboratory of Medicinal Chemical Biology and College of Pharmacy, Tianjin, 300350, China
| | - Yang Chen
- Tianjin Nankai University State Key Laboratory of Medicinal Chemical Biology and College of Pharmacy, Tianjin, 300350, China
| | - Yi-Nan Li
- Tianjin Nankai University State Key Laboratory of Medicinal Chemical Biology and College of Pharmacy, Tianjin, 300350, China
| | - Heng Zhang
- Tianjin Nankai University State Key Laboratory of Medicinal Chemical Biology and College of Pharmacy, Tianjin, 300350, China
- Tianjin International Joint Academy of Biomedicine, Tianjin, 300450, China
| | - Xiu Huang
- Tianjin Nankai University State Key Laboratory of Medicinal Chemical Biology and College of Pharmacy, Tianjin, 300350, China
- Tianjin International Joint Academy of Biomedicine, Tianjin, 300450, China
| | - Ying-Ying Li
- Tianjin Nankai University State Key Laboratory of Medicinal Chemical Biology and College of Pharmacy, Tianjin, 300350, China
| | - Zhi-Yang Li
- Tianjin Nankai University State Key Laboratory of Medicinal Chemical Biology and College of Pharmacy, Tianjin, 300350, China
- Tianjin International Joint Academy of Biomedicine, Tianjin, 300450, China
| | - Jing-Xia Han
- Tianjin Nankai University State Key Laboratory of Medicinal Chemical Biology and College of Pharmacy, Tianjin, 300350, China
- Tianjin International Joint Academy of Biomedicine, Tianjin, 300450, China
| | - Xin-Ying Wu
- Tianjin Nankai University State Key Laboratory of Medicinal Chemical Biology and College of Pharmacy, Tianjin, 300350, China
| | - Hui-Juan Liu
- Tianjin Nankai University State Key Laboratory of Medicinal Chemical Biology and College of Pharmacy, Tianjin, 300350, China
- Tianjin International Joint Academy of Biomedicine, Tianjin, 300450, China
| | - Tao Sun
- Tianjin Nankai University State Key Laboratory of Medicinal Chemical Biology and College of Pharmacy, Tianjin, 300350, China
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McCulloch MK, Mehryab F, Rashnonejad A. Navigating the Landscape of CMT1B: Understanding Genetic Pathways, Disease Models, and Potential Therapeutic Approaches. Int J Mol Sci 2024; 25:9227. [PMID: 39273178 PMCID: PMC11395143 DOI: 10.3390/ijms25179227] [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: 06/16/2024] [Revised: 08/13/2024] [Accepted: 08/19/2024] [Indexed: 09/15/2024] Open
Abstract
Charcot-Marie-Tooth type 1B (CMT1B) is a peripheral neuropathy caused by mutations in the gene encoding myelin protein zero (MPZ), a key component of the myelin sheath in Schwann cells. Mutations in the MPZ gene can lead to protein misfolding, unfolded protein response (UPR), endoplasmic reticulum (ER) stress, or protein mistrafficking. Despite significant progress in understanding the disease mechanisms, there is currently no effective treatment for CMT1B, with therapeutic strategies primarily focused on supportive care. Gene therapy represents a promising therapeutic approach for treating CMT1B. To develop a treatment and better design preclinical studies, an in-depth understanding of the pathophysiological mechanisms and animal models is essential. In this review, we present a comprehensive overview of the disease mechanisms, preclinical models, and recent advancements in therapeutic research for CMT1B, while also addressing the existing challenges in the field. This review aims to deepen the understanding of CMT1B and to encourage further research towards the development of effective treatments for CMT1B patients.
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Affiliation(s)
- Mary Kate McCulloch
- Center for Gene Therapy, The Abigail Wexner Research Institute at Nationwide Children's Hospital, 575 Children's Crossroad, Columbus, OH 43215, USA
- Molecular, Cellular, and Developmental Biology Program, The Ohio State University, Columbus, OH 43210, USA
| | - Fatemeh Mehryab
- Center for Gene Therapy, The Abigail Wexner Research Institute at Nationwide Children's Hospital, 575 Children's Crossroad, Columbus, OH 43215, USA
| | - Afrooz Rashnonejad
- Center for Gene Therapy, The Abigail Wexner Research Institute at Nationwide Children's Hospital, 575 Children's Crossroad, Columbus, OH 43215, USA
- Molecular, Cellular, and Developmental Biology Program, The Ohio State University, Columbus, OH 43210, USA
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Grove M, Kim H, Pang S, Amaya JP, Hu G, Zhou J, Lemay M, Son YJ. TEAD1 is crucial for developmental myelination, Remak bundles, and functional regeneration of peripheral nerves. eLife 2024; 13:e87394. [PMID: 38456457 PMCID: PMC10959528 DOI: 10.7554/elife.87394] [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: 03/15/2023] [Accepted: 03/06/2024] [Indexed: 03/09/2024] Open
Abstract
Previously we showed that the hippo pathway transcriptional effectors, YAP and TAZ, are essential for Schwann cells (SCs) to develop, maintain and regenerate myelin . Although TEAD1 has been implicated as a partner transcription factor, the mechanisms by which it mediates YAP/TAZ regulation of SC myelination are unclear. Here, using conditional and inducible knockout mice, we show that TEAD1 is crucial for SCs to develop and regenerate myelin. It promotes myelination by both positively and negatively regulating SC proliferation, enabling Krox20/Egr2 to upregulate myelin proteins, and upregulating the cholesterol biosynthetic enzymes FDPS and IDI1. We also show stage-dependent redundancy of TEAD1 and that non-myelinating SCs have a unique requirement for TEAD1 to enwrap nociceptive axons in Remak bundles. Our findings establish TEAD1 as a major partner of YAP/TAZ in developmental myelination and functional nerve regeneration and as a novel transcription factor regulating Remak bundle integrity.
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Affiliation(s)
- Matthew Grove
- Department of Neural Sciences, Shriners Hospitals Pediatric Research Center, Lewis Katz School of Medicine, Temple UniversityPhiladelphiaUnited States
| | - Hyukmin Kim
- Department of Neural Sciences, Shriners Hospitals Pediatric Research Center, Lewis Katz School of Medicine, Temple UniversityPhiladelphiaUnited States
| | - Shuhuan Pang
- Department of Neural Sciences, Shriners Hospitals Pediatric Research Center, Lewis Katz School of Medicine, Temple UniversityPhiladelphiaUnited States
| | - Jose Paz Amaya
- Department of Bioengineering, Temple UniversityPhiladelphiaUnited States
| | - Guoqing Hu
- Department of Pharmacology & Toxicology, Medical College of Georgia, Augusta UniversityAugustaUnited States
| | - Jiliang Zhou
- Department of Pharmacology & Toxicology, Medical College of Georgia, Augusta UniversityAugustaUnited States
| | - Michel Lemay
- Department of Bioengineering, Temple UniversityPhiladelphiaUnited States
| | - Young-Jin Son
- Department of Neural Sciences, Shriners Hospitals Pediatric Research Center, Lewis Katz School of Medicine, Temple UniversityPhiladelphiaUnited States
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4
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Grove M, Kim H, Pang S, Amaya JP, Hu G, Zhou J, Lemay M, Son YJ. TEAD1 is crucial for developmental myelination, Remak bundles, and functional regeneration of peripheral nerves. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.02.27.530298. [PMID: 38293102 PMCID: PMC10827063 DOI: 10.1101/2023.02.27.530298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
Previously we showed that the hippo pathway transcriptional effectors, YAP and TAZ, are essential for Schwann cells (SCs) to develop, maintain and regenerate myelin (Grove et al., 2017; Grove, Lee, Zhao, & Son, 2020). Although TEAD1 has been implicated as a partner transcription factor, the mechanisms by which it mediates YAP/TAZ regulation of SC myelination are unclear. Here, using conditional and inducible knockout mice, we show that TEAD1 is crucial for SCs to develop and regenerate myelin. It promotes myelination by both positively and negatively regulating SC proliferation, enabling Krox20/Egr2 to upregulate myelin proteins, and upregulating the cholesterol biosynthetic enzymes FDPS and IDI1. We also show stage-dependent redundancy of TEAD1 and that non-myelinating SCs have a unique requirement for TEAD1 to enwrap nociceptive axons in Remak bundles. Our findings establish TEAD1 as a major partner of YAP/TAZ in developmental myelination and functional nerve regeneration and as a novel transcription factor regulating Remak bundle integrity.
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Itson-Zoske B, Gani U, Mikesell A, Qiu C, Fan F, Stucky C, Hogan Q, Shin SM, Yu H. Selective RNAi-silencing of Schwann cell Piezo1 alleviates mechanical hypersensitization following peripheral nerve injury. RESEARCH SQUARE 2023:rs.3.rs-3405016. [PMID: 37886453 PMCID: PMC10602140 DOI: 10.21203/rs.3.rs-3405016/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2023]
Abstract
We previously reported functional Piezo1 expression in Schwann cells of the peripheral nervous system. This study is designed to further investigate the role of Schwann cell Piezo1 in peripheral nociception. We first developed an adeno-associated viral (AAV) vector that has primary Schwann cell tropism after delivery into the sciatic nerve. This was achieved by packing AAV-GFP transcribed by a hybrid CMV enhancer/chicken β-actin (CBA) promoter using a capsid AAVolig001 to generate AAVolig001-CBA-GFP. Five weeks after intrasciatic injection of AAVolig001-CBA-GFP in naïve rats, GFP expression was detected selectively in the Schwann cells of the sciatic nerve. A short hairpin RNA against rat Piezo1 (PZ1shRNA) was designed that showed efficient physical and functional knockdown of Piezo1 in NG108 neuronal cells. A dual promoter and bidirectional AAV encoding a U6-driven PZ1shRNA and CBA-transcribed GFP was packed with capsid olig001 (AAVolig001-PZ1shRNA), and AAV was injected into unilateral sciatic nerve immediately after induction of common peroneal nerve injury (CPNI). Results showed that the development of mechanical hypersensitivity in the CPNI rats injected with AAVolig001-PZ1shRNA was mitigated, compared to rats subjected with AAVolig001-scramble. Selective in vivo Schwann cell transduction and functional block of Piezo1 channel activity of primary cultured Schwann cells was confirmed. Together, our data demonstrate that 1) AAVolig001 has unique and selective primary tropism to Schwann cells via intrasciatic delivery and 2) Schwann cell Piezo1 contributes to mechanical hypersensitivity following nerve injury.
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Trangle SS, Rosenberg T, Parnas H, Levy G, Bar E, Marco A, Barak B. In individuals with Williams syndrome, dysregulation of methylation in non-coding regions of neuronal and oligodendrocyte DNA is associated with pathology and cortical development. Mol Psychiatry 2023; 28:1112-1127. [PMID: 36577841 DOI: 10.1038/s41380-022-01921-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Revised: 12/03/2022] [Accepted: 12/12/2022] [Indexed: 12/29/2022]
Abstract
Williams syndrome (WS) is a neurodevelopmental disorder caused by a heterozygous micro-deletion in the WS critical region (WSCR) and is characterized by hyper-sociability and neurocognitive abnormalities. Nonetheless, whether and to what extent WSCR deletion leads to epigenetic modifications in the brain and induces pathological outcomes remains largely unknown. By examining DNA methylation in frontal cortex, we revealed genome-wide disruption in the methylome of individuals with WS, as compared to typically developed (TD) controls. Surprisingly, differentially methylated sites were predominantly annotated as introns and intergenic loci and were found to be highly enriched around binding sites for transcription factors that regulate neuronal development, plasticity and cognition. Moreover, by utilizing enhancer-promoter interactome data, we confirmed that most of these loci function as active enhancers in the human brain or as target genes of transcriptional networks associated with myelination, oligodendrocyte (OL) differentiation, cognition and social behavior. Cell type-specific methylation analysis revealed aberrant patterns in the methylation of active enhancers in neurons and OLs, and important neuron-glia interactions that might be impaired in individuals with WS. Finally, comparison of methylation profiles from blood samples of individuals with WS and healthy controls, along with other data collected in this study, identified putative targets of endophenotypes associated with WS, which can be used to define brain-risk loci for WS outside the WSCR locus, as well as for other associated pathologies. In conclusion, our study illuminates the brain methylome landscape of individuals with WS and sheds light on how these aberrations might be involved in social behavior and physiological abnormalities. By extension, these results may lead to better diagnostics and more refined therapeutic targets for WS.
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Affiliation(s)
- Sari Schokoroy Trangle
- The School of Psychological Sciences, Faculty of Social Sciences, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Tali Rosenberg
- Neuro-Epigenetics Laboratory, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, 7610001, Israel
| | - Hadar Parnas
- Neuro-Epigenetics Laboratory, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, 7610001, Israel
| | - Gilad Levy
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Ela Bar
- The School of Psychological Sciences, Faculty of Social Sciences, Tel Aviv University, Tel Aviv, 6997801, Israel.,The School of Neurobiology, Biochemistry & Biophysics, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Asaf Marco
- Neuro-Epigenetics Laboratory, Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, 7610001, Israel.
| | - Boaz Barak
- The School of Psychological Sciences, Faculty of Social Sciences, Tel Aviv University, Tel Aviv, 6997801, Israel. .,Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, 6997801, Israel.
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Lakhssassi K, Sarto MP, Marín B, Lahoz B, Folch J, Alabart JL, Serrano M, Calvo JH. Exploring differentially expressed genes in hypothalamic, pars tuberalis and pineal gland transcriptomes in different sexual behavior phenotypes in rams using RNA-Seq. J Anim Sci 2023; 101:skac365. [PMID: 36331073 PMCID: PMC9833037 DOI: 10.1093/jas/skac365] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2022] [Accepted: 11/02/2022] [Indexed: 11/06/2022] Open
Abstract
Reproductive seasonality is a limiting factor in sheep production. Sexual behavior is a key element in reproductive efficiency, and this function is regulated by the hypothalamus-pituitary-gonadal (HPG) axis. To understand the mechanisms of sexual behavior, transcriptomic sequencing technology was used to identify differentially expressed genes (DEGs) in the hypothalamus (HT), pars tuberalis (PT) and pineal gland (PG) in Rasa Aragonesa rams with different sexual behavior. Bioinformatics analysis of the 16,401 identified genes by RNA-Seq revealed 103 and 12 DEGs in the HT and the PG, respectively, at a false discovery rate (FDR) of 5% with an absolute value of expression ≥ 1 (log2FC). However, no DEGs were found in the PT. Functional annotation and pathway enrichment analysis showed that DEGs of HT were enriched mainly in neuroactive ligand-receptor interactions and signaling pathways, including notable candidate genes such as MTNR1A, CHRNA2, FSHB, LHB, GNRHR, AVP, PRL, PDYN, CGA, GABRD, and TSHB, which play a crucial role in sexual behavior. The GnRH and cAMP signaling pathways were also highlighted. In addition, gene set enrichment analysis (GSEA) identified potential pathways, dominated mainly by biological process category, that could be responsible for the differences in sexual behavior observed in rams. The intracellular protein transport and pattern specification process were enriched within the PT and the transcription factor binding and protein ubiquitination pathways for the PG. Thus, these pathways together may play an important role in the regulation of the sexual behavior in Rasa Aragonesa rams through the hypothalamic-pituitary-gonadal axis. The validation of 5 DEGs using reverse transcription quantitative polymerase chain reaction (RT-qPCR) showed expression patterns like the found with RNA-Seq. Overall, these results contribute to understanding the genomic basis of sexual behavior in rams. Our study demonstrates that multiple networks and pathways orchestrate sexual behavior in sheep.
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Affiliation(s)
- Kenza Lakhssassi
- Agrifood Research and Technology Centre of Aragon-IA2, 50059 Zaragoza, Spain
- INRA Instituts, 6356 Rabat, Morocco
| | - María Pilar Sarto
- Agrifood Research and Technology Centre of Aragon-IA2, 50059 Zaragoza, Spain
| | - Belén Marín
- Centre for Encephalopathies and Emerging Transmissible Diseases, Faculty of Veterinary Medicine, University of Zaragoza, 50018 Zaragoza, Spain
| | - Belén Lahoz
- Agrifood Research and Technology Centre of Aragon-IA2, 50059 Zaragoza, Spain
| | - José Folch
- Agrifood Research and Technology Centre of Aragon-IA2, 50059 Zaragoza, Spain
| | - José Luis Alabart
- Agrifood Research and Technology Centre of Aragon-IA2, 50059 Zaragoza, Spain
| | - Malena Serrano
- Department of Animal Breeding and Genetics, INIA-CSIC, 28040 Madrid, Spain
| | - Jorge Hugo Calvo
- Agrifood Research and Technology Centre of Aragon-IA2, 50059 Zaragoza, Spain
- ARAID, 50018 Zaragoza, Spain
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8
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Duman M, Jaggi S, Enz LS, Jacob C, Schaeren-Wiemers N. Theophylline Induces Remyelination and Functional Recovery in a Mouse Model of Peripheral Neuropathy. Biomedicines 2022; 10:biomedicines10061418. [PMID: 35740439 PMCID: PMC9219657 DOI: 10.3390/biomedicines10061418] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 06/05/2022] [Accepted: 06/07/2022] [Indexed: 11/16/2022] Open
Abstract
Charcot-Marie-Tooth disease (CMT) is a large group of inherited peripheral neuropathies that are primarily due to demyelination and/or axonal degeneration. CMT type 1A (CMT1A), which is caused by the duplication of the peripheral myelin protein 22 (PMP22) gene, is a demyelinating and the most frequent CMT subtype. Hypermyelination, demyelination, and secondary loss of large-caliber axons are hallmarks of CMT1A, and there is currently no cure and no efficient treatment to alleviate the symptoms of the disease. We previously showed that histone deacetylases 1 and 2 (HDAC1/2) are critical for Schwann cell developmental myelination and remyelination after a sciatic nerve crush lesion. We also demonstrated that a short-term treatment with Theophylline, which is a potent activator of HDAC2, enhances remyelination and functional recovery after a sciatic nerve crush lesion in mice. In the present study, we tested whether Theophylline treatment could also lead to (re)myelination in a PMP22-overexpressing mouse line (C22) modeling CMT1A. Indeed, we show here that a short-term treatment with Theophylline in C22 mice increases the percentage of myelinated large-caliber axons and the expression of the major peripheral myelin protein P0 and induces functional recovery. This pilot study suggests that Theophylline treatment could be beneficial to promote myelination and thereby prevent axonal degeneration and enhance functional recovery in CMT1A patients.
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Affiliation(s)
- Mert Duman
- Department of Biology, University of Fribourg, 1700 Fribourg, Switzerland;
- Faculty of Biology, Institute of Developmental Biology and Neurobiology, Johannes Gutenberg University Mainz, 55128 Mainz, Germany
| | - Stephanie Jaggi
- Department of Biomedicine, University Hospital Basel, 4031 Basel, Switzerland; (S.J.); (L.S.E.); (N.S.-W.)
| | - Lukas Simon Enz
- Department of Biomedicine, University Hospital Basel, 4031 Basel, Switzerland; (S.J.); (L.S.E.); (N.S.-W.)
| | - Claire Jacob
- Department of Biology, University of Fribourg, 1700 Fribourg, Switzerland;
- Faculty of Biology, Institute of Developmental Biology and Neurobiology, Johannes Gutenberg University Mainz, 55128 Mainz, Germany
- Correspondence:
| | - Nicole Schaeren-Wiemers
- Department of Biomedicine, University Hospital Basel, 4031 Basel, Switzerland; (S.J.); (L.S.E.); (N.S.-W.)
- Department of Biomedicine, University of Basel, 4058 Basel, Switzerland
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9
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Della-Flora Nunes G, Wilson ER, Hurley E, He B, O'Malley BW, Poitelon Y, Wrabetz L, Feltri ML. Activation of mTORC1 and c-Jun by Prohibitin1 loss in Schwann cells may link mitochondrial dysfunction to demyelination. eLife 2021; 10:e66278. [PMID: 34519641 PMCID: PMC8478418 DOI: 10.7554/elife.66278] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 09/13/2021] [Indexed: 12/26/2022] Open
Abstract
Schwann cell (SC) mitochondria are quickly emerging as an important regulator of myelin maintenance in the peripheral nervous system (PNS). However, the mechanisms underlying demyelination in the context of mitochondrial dysfunction in the PNS are incompletely understood. We recently showed that conditional ablation of the mitochondrial protein Prohibitin 1 (PHB1) in SCs causes a severe and fast progressing demyelinating peripheral neuropathy in mice, but the mechanism that causes failure of myelin maintenance remained unknown. Here, we report that mTORC1 and c-Jun are continuously activated in the absence of Phb1, likely as part of the SC response to mitochondrial damage. Moreover, we demonstrate that these pathways are involved in the demyelination process, and that inhibition of mTORC1 using rapamycin partially rescues the demyelinating pathology. Therefore, we propose that mTORC1 and c-Jun may play a critical role as executioners of demyelination in the context of perturbations to SC mitochondria.
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Affiliation(s)
- Gustavo Della-Flora Nunes
- Hunter James Kelly Research Institute, University at BuffaloBuffaloUnited States
- Department of Biochemistry, University at BuffaloBuffaloUnited States
| | - Emma R Wilson
- Hunter James Kelly Research Institute, University at BuffaloBuffaloUnited States
- Department of Biochemistry, University at BuffaloBuffaloUnited States
| | - Edward Hurley
- Hunter James Kelly Research Institute, University at BuffaloBuffaloUnited States
| | - Bin He
- Immunobiology & Transplant Science Center and Department of Surgery, Houston Methodist HospitalHoustonUnited States
| | - Bert W O'Malley
- Department of Medicine and Molecular and Cellular Biology, Baylor College of MedicineHoustonUnited States
| | - Yannick Poitelon
- Department of Neuroscience and Experimental Therapeutics, Albany Medical CollegeAlbanyUnited States
| | - Lawrence Wrabetz
- Hunter James Kelly Research Institute, University at BuffaloBuffaloUnited States
- Department of Biochemistry, University at BuffaloBuffaloUnited States
- Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at BuffaloBuffaloUnited States
| | - M Laura Feltri
- Hunter James Kelly Research Institute, University at BuffaloBuffaloUnited States
- Department of Biochemistry, University at BuffaloBuffaloUnited States
- Department of Neurology, Jacobs School of Medicine and Biomedical Sciences, University at BuffaloBuffaloUnited States
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10
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Wrestling and Wrapping: A Perspective on SUMO Proteins in Schwann Cells. Biomolecules 2021; 11:biom11071055. [PMID: 34356679 PMCID: PMC8301837 DOI: 10.3390/biom11071055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 07/12/2021] [Accepted: 07/13/2021] [Indexed: 11/20/2022] Open
Abstract
Schwann cell development and peripheral nerve myelination are finely orchestrated multistep processes; some of the underlying mechanisms are well described and others remain unknown. Many posttranslational modifications (PTMs) like phosphorylation and ubiquitination have been reported to play a role during the normal development of the peripheral nervous system (PNS) and in demyelinating neuropathies. However, a relatively novel PTM, SUMOylation, has not been studied in these contexts. SUMOylation involves the covalent attachment of one or more small ubiquitin-like modifier (SUMO) proteins to a substrate, which affects the function, cellular localization, and further PTMs of the conjugated protein. SUMOylation also regulates other proteins indirectly by facilitating non-covalent protein–protein interaction via SUMO interaction motifs (SIM). This pathway has important consequences on diverse cellular processes, and dysregulation of this pathway has been reported in several diseases including neurological and degenerative conditions. In this article, we revise the scarce literature on SUMOylation in Schwann cells and the PNS, we propose putative substrate proteins, and we speculate on potential mechanisms underlying the possible involvement of this PTM in peripheral myelination and neuropathies.
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11
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Simankova A, Bizen N, Saitoh S, Shibata S, Ohno N, Abe M, Sakimura K, Takebayashi H. Ddx20, DEAD box helicase 20, is essential for the differentiation of oligodendrocyte and maintenance of myelin gene expression. Glia 2021; 69:2559-2574. [PMID: 34231259 DOI: 10.1002/glia.24058] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 06/24/2021] [Accepted: 06/25/2021] [Indexed: 12/17/2022]
Abstract
Oligodendrocytes form myelin sheaths that surround axons, contributing to saltatory conduction and proper central nervous system (CNS) function. Oligodendrocyte progenitor cells (OPCs) are generated during the embryonic stage and differentiate into myelinating oligodendrocytes postnatally. Ddx20 is a multifunctional, DEAD-box helicase involved in multiple cellular processes, including transcription, splicing, microRNA biogenesis, and translation. Although defects in each of these processes result in abnormal oligodendrocyte differentiation and myelination, the involvement of Ddx20 in oligodendrocyte terminal differentiation remains unknown. To address this question, we used Mbp-Cre mice to generate Ddx20 conditional knockout (cKO) mice to allow for the deletion of Ddx20 from mature oligodendrocytes. Mbp-Cre;Ddx20 cKO mice demonstrated small body sizes, behavioral abnormalities, muscle weakness, and short lifespans, with mortality by the age of 2 months old. Histological analyses demonstrated significant reductions in the number of mature oligodendrocytes and drastic reductions in the expression levels of myelin-associated mRNAs, such as Mbp and Plp at postnatal day 42. The number of OPCs did not change. A thin myelin layer was observed for large-diameter axons in Ddx20 cKO mice, based on electron microscopic analysis. A bromodeoxyuridine (BrdU) labeling experiment demonstrated that terminal differentiation was perturbed from ages 2 weeks to 7 weeks in the CNS of Mbp-Cre;Ddx20 cKO mice. The activation of mitogen-activated protein (MAP) kinase, which promotes myelination, was downregulated in the Ddx20 cKO mice based on immunohistochemical detection. These results indicate that Ddx20 is an essential factor for terminal differentiation of oligodendrocytes and maintenance of myelin gene expression.
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Affiliation(s)
- Anna Simankova
- Division of Neurobiology and Anatomy, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan
| | - Norihisa Bizen
- Division of Neurobiology and Anatomy, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan
| | - Sei Saitoh
- Section of Electron Microscopy, Supportive Center for Brain Research, National Institute for Physiological Sciences, Okazaki, Japan.,Department of Biomedical Molecular Sciences (Anatomy II), Fujita Health University School of Medicine, Toyoake, Japan
| | - Shinsuke Shibata
- Division of Microscopic Anatomy, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan
| | - Nobuhiko Ohno
- Department of Anatomy, Division of Histology and Cell Biology, School of Medicine, Jichi Medical University, Shimotsuke, Japan.,Division of Ultrastructural Research, National Institute for Physiological Sciences, Okazaki, Japan
| | - Manabu Abe
- Department of Animal Model Development, Brain Research Institute, Niigata University, Niigata, Japan
| | - Kenji Sakimura
- Department of Animal Model Development, Brain Research Institute, Niigata University, Niigata, Japan
| | - Hirohide Takebayashi
- Division of Neurobiology and Anatomy, Graduate School of Medical and Dental Sciences, Niigata University, Niigata, Japan.,Center for Coordination of Research Facilities, Niigata University, Niigata, Japan
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12
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Llorente IL, Xie Y, Mazzitelli JA, Hatanaka EA, Cinkornpumin J, Miller DR, Lin Y, Lowry WE, Carmichael ST. Patient-derived glial enriched progenitors repair functional deficits due to white matter stroke and vascular dementia in rodents. Sci Transl Med 2021; 13:13/590/eaaz6747. [PMID: 33883275 DOI: 10.1126/scitranslmed.aaz6747] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 10/05/2020] [Accepted: 01/16/2021] [Indexed: 01/24/2023]
Abstract
Subcortical white matter stroke (WMS) accounts for up to 30% of all stroke events. WMS damages primarily astrocytes, axons, oligodendrocytes, and myelin. We hypothesized that a therapeutic intervention targeting astrocytes would be ideally suited for brain repair after WMS. We characterize the cellular properties and in vivo tissue repair activity of glial enriched progenitor (GEP) cells differentiated from human-induced pluripotent stem cells, termed hiPSC-derived GEPs (hiPSC-GEPs). hiPSC-GEPs are derived from hiPSC-neural progenitor cells via an experimental manipulation of hypoxia inducible factor activity by brief treatment with a prolyl hydroxylase inhibitor, deferoxamine. This treatment permanently biases these cells to further differentiate toward an astrocyte fate. hiPSC-GEPs transplanted into the brain in the subacute period after WMS in mice migrated widely, matured into astrocytes with a prorepair phenotype, induced endogenous oligodendrocyte precursor proliferation and remyelination, and promoted axonal sprouting. hiPSC-GEPs enhanced motor and cognitive recovery compared to other hiPSC-differentiated cell types. This approach establishes an hiPSC-derived product with easy scale-up capabilities that might be effective for treating WMS.
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Affiliation(s)
- Irene L Llorente
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Yuan Xie
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL 60637, USA
| | - Jose A Mazzitelli
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Emily A Hatanaka
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA.,Department of Molecular, Cell and Developmental Biology, UCLA, Los Angeles, CA 90095, USA
| | - Jessica Cinkornpumin
- Department of Molecular, Cell and Developmental Biology, UCLA, Los Angeles, CA 90095, USA
| | - David R Miller
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Ying Lin
- Department of Molecular, Cell and Developmental Biology, UCLA, Los Angeles, CA 90095, USA
| | - William E Lowry
- Department of Molecular, Cell and Developmental Biology, UCLA, Los Angeles, CA 90095, USA.
| | - S Thomas Carmichael
- Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA.
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13
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Balakrishnan A, Belfiore L, Chu TH, Fleming T, Midha R, Biernaskie J, Schuurmans C. Insights Into the Role and Potential of Schwann Cells for Peripheral Nerve Repair From Studies of Development and Injury. Front Mol Neurosci 2021; 13:608442. [PMID: 33568974 PMCID: PMC7868393 DOI: 10.3389/fnmol.2020.608442] [Citation(s) in RCA: 61] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Accepted: 12/31/2020] [Indexed: 12/13/2022] Open
Abstract
Peripheral nerve injuries arising from trauma or disease can lead to sensory and motor deficits and neuropathic pain. Despite the purported ability of the peripheral nerve to self-repair, lifelong disability is common. New molecular and cellular insights have begun to reveal why the peripheral nerve has limited repair capacity. The peripheral nerve is primarily comprised of axons and Schwann cells, the supporting glial cells that produce myelin to facilitate the rapid conduction of electrical impulses. Schwann cells are required for successful nerve regeneration; they partially “de-differentiate” in response to injury, re-initiating the expression of developmental genes that support nerve repair. However, Schwann cell dysfunction, which occurs in chronic nerve injury, disease, and aging, limits their capacity to support endogenous repair, worsening patient outcomes. Cell replacement-based therapeutic approaches using exogenous Schwann cells could be curative, but not all Schwann cells have a “repair” phenotype, defined as the ability to promote axonal growth, maintain a proliferative phenotype, and remyelinate axons. Two cell replacement strategies are being championed for peripheral nerve repair: prospective isolation of “repair” Schwann cells for autologous cell transplants, which is hampered by supply challenges, and directed differentiation of pluripotent stem cells or lineage conversion of accessible somatic cells to induced Schwann cells, with the potential of “unlimited” supply. All approaches require a solid understanding of the molecular mechanisms guiding Schwann cell development and the repair phenotype, which we review herein. Together these studies provide essential context for current efforts to design glial cell-based therapies for peripheral nerve regeneration.
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Affiliation(s)
- Anjali Balakrishnan
- Biological Sciences Platform, Sunnybrook Research Institute (SRI), Toronto, ON, Canada.,Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Lauren Belfiore
- Biological Sciences Platform, Sunnybrook Research Institute (SRI), Toronto, ON, Canada.,Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Tak-Ho Chu
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Taylor Fleming
- Biological Sciences Platform, Sunnybrook Research Institute (SRI), Toronto, ON, Canada
| | - Rajiv Midha
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Jeff Biernaskie
- Department of Comparative Biology and Experimental Medicine, Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
| | - Carol Schuurmans
- Biological Sciences Platform, Sunnybrook Research Institute (SRI), Toronto, ON, Canada.,Department of Biochemistry, University of Toronto, Toronto, ON, Canada.,Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
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14
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Combined Use of Chitosan and Olfactory Mucosa Mesenchymal Stem/Stromal Cells to Promote Peripheral Nerve Regeneration In Vivo. Stem Cells Int 2021; 2021:6613029. [PMID: 33488738 PMCID: PMC7801080 DOI: 10.1155/2021/6613029] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 11/27/2020] [Accepted: 12/10/2020] [Indexed: 12/20/2022] Open
Abstract
Peripheral nerve injury remains a clinical challenge with severe physiological and functional consequences. Despite the existence of multiple possible therapeutic approaches, until now, there is no consensus regarding the advantages of each option or the best methodology in promoting nerve regeneration. Regenerative medicine is a promise to overcome this medical limitation, and in this work, chitosan nerve guide conduits and olfactory mucosa mesenchymal stem/stromal cells were applied in different therapeutic combinations to promote regeneration in sciatic nerves after neurotmesis injury. Over 20 weeks, the intervened animals were subjected to a regular functional assessment (determination of motor performance, nociception, and sciatic indexes), and after this period, they were evaluated kinematically and the sciatic nerves and cranial tibial muscles were evaluated stereologically and histomorphometrically, respectively. The results obtained allowed confirming the beneficial effects of using these therapeutic approaches. The use of chitosan NGCs and cells resulted in better motor performance, better sciatic indexes, and lower gait dysfunction after 20 weeks. The use of only NGGs demonstrated better nociceptive recoveries. The stereological evaluation of the sciatic nerve revealed identical values in the different parameters for all therapeutic groups. In the muscle histomorphometric evaluation, the groups treated with NGCs and cells showed results close to those of the group that received traditional sutures, the one with the best final values. The therapeutic combinations studied show promising outcomes and should be the target of new future works to overcome some irregularities found in the results and establish the combination of nerve guidance conduits and olfactory mucosa mesenchymal stem/stromal cells as viable options in the treatment of peripheral nerves after injury.
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15
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Fei Y, Yu H, Huang S, Chen P, Pan L. Expression and prognostic analyses of early growth response proteins (EGRs) in human breast carcinoma based on database analysis. PeerJ 2019; 7:e8183. [PMID: 31844579 PMCID: PMC6907094 DOI: 10.7717/peerj.8183] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 11/10/2019] [Indexed: 12/13/2022] Open
Abstract
Background Early growth response proteins (EGRs), as a transcriptional regulatory family, are involved in the process of cell growth, differentiation, apoptosis, and even carcinogenesis. However, the role of EGRs in tumors, their expression levels, and their prognostic value remain unclear. Methods Using the Oncomine database, Kaplan–Meier Plotter, bcGenExMiner v4.2, cBioPortal, and other tools, the association between the survival data of breast carcinoma (BC) patients and transcriptional levels of four EGRs was investigated. Results According to the Oncomine database, in comparison to normal tissues, the expression level of EGR2/3 mRNA in BC tissues was decreased, but there was no difference in the expression level of EGR4 mRNA. On the basis of the Scarff-Bloom-Richardson (SBR) grading system, the downregulated expression level of EGR1/2/3 and upregulated expression level of EGR4 were correlated with an increased histological differentiation level, with significant differences (p < 0.05). Kaplan–Meier curves suggest that a reduction in EGR2/3 mRNA expression is related to recurrence-free survival (RFS) in BC patients. In addition, the mRNA expression level of EGR1/2/3 was related to metastatic relapse-free survival (MRFS) in BC patients with metastatic recurrence (p < 0.05). Conclusion EGR1/2/3 can be utilized as an important factor for evaluating prognosis and may be relevant to diagnosis. EGR4 may play a role in the occurrence and development of BC. The specific function and mechanism of EGRs in BC deserve further study.
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Affiliation(s)
- Yuchang Fei
- The First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, Zhejiang Province, China
| | - Huan Yu
- Ningbo Yinzhou Second Hospital, Ningbo, Zhejiang Province, China
| | - Shuo Huang
- The Third Clinical Medical Institute of Zhejiang Chinese Medical University, Zhejiang Province, China
| | - Peifeng Chen
- The First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, Zhejiang Province, China
| | - Lei Pan
- The First Affiliated Hospital of Zhejiang Chinese Medical University, Hangzhou, Zhejiang Province, China
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16
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Sock E, Wegner M. Transcriptional control of myelination and remyelination. Glia 2019; 67:2153-2165. [PMID: 31038810 DOI: 10.1002/glia.23636] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Revised: 04/01/2019] [Accepted: 04/11/2019] [Indexed: 12/11/2022]
Abstract
Myelination is an evolutionary recent differentiation program that has been independently acquired in vertebrates by Schwann cells in the peripheral nervous system and oligodendrocytes in the central nervous system. Therefore, it is not surprising that regulating transcription factors differ substantially between both cell types. However, overall principles are similar as transcriptional control in Schwann cells and oligodendrocytes combines lineage determining and stage-specific factors in complex regulatory networks. Myelination does not only occur during development, but also as remyelination in the adult. In line with the different conditions during developmental myelination and remyelination and the distinctive properties of Schwann cells and oligodendrocytes, transcriptional regulation of remyelination exhibits unique features and differs between the two cell types. This review gives an overview of the current state in the field.
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Affiliation(s)
- Elisabeth Sock
- Institut für Biochemie, Emil-Fischer-Zentrum, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
| | - Michael Wegner
- Institut für Biochemie, Emil-Fischer-Zentrum, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany
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17
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Pantera H, Moran JJ, Hung HA, Pak E, Dutra A, Svaren J. Regulation of the neuropathy-associated Pmp22 gene by a distal super-enhancer. Hum Mol Genet 2019; 27:2830-2839. [PMID: 29771329 DOI: 10.1093/hmg/ddy191] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 05/09/2018] [Indexed: 12/27/2022] Open
Abstract
Peripheral nerve myelination is adversely affected in the most common form of the hereditary peripheral neuropathy called Charcot-Marie-Tooth Disease. This form, classified as CMT1A, is caused by a 1.4 Mb duplication on chromosome 17, which includes the abundantly expressed Schwann cell myelin gene, Peripheral Myelin Protein 22 (PMP22). This is one of the most common copy number variants causing neurological disease. Overexpression of Pmp22 in rodent models recapitulates several aspects of neuropathy, and reduction of Pmp22 in such models results in amelioration of the neuropathy phenotype. Recently we identified a potential super-enhancer approximately 90-130 kb upstream of the Pmp22 transcription start sites. This super-enhancer encompasses a cluster of individual enhancers that have the acetylated histone H3K27 active enhancer mark, and coincides with smaller duplications identified in patients with milder CMT1A-like symptoms, where the PMP22 coding region itself was not part of the duplication. In this study, we have utilized genome editing to create a deletion of this super-enhancer to determine its role in Pmp22 regulation. Our data show a significant decrease in Pmp22 transcript expression using allele-specific internal controls. Moreover, the P2 promoter of the Pmp22 gene, which is used in other cell types, is affected, but we find that the Schwann cell-specific P1 promoter is disproportionately more sensitive to loss of the super-enhancer. These data show for the first time the requirement of these upstream enhancers for full Pmp22 expression.
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Affiliation(s)
- Harrison Pantera
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA.,Molecular and Cellular Pharmacology Graduate Program, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - John J Moran
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Holly A Hung
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Evgenia Pak
- Cytogenetics and Microscopy Core, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Amalia Dutra
- Cytogenetics and Microscopy Core, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, 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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18
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MicroRNAs 93-5p, 106b-5p, 17-5p, and 140-5p target the expression of early growth response protein 2 in Schwann cells. Neuroreport 2019; 30:241-246. [PMID: 30614908 DOI: 10.1097/wnr.0000000000001193] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Early growth response protein 2 (EGR2) is an essential transcription factor for peripheral nerve myelination. Schwann cells (SCs), the peripheral myelin-forming glial cells, express high levels of EGR2 during postnatal myelination. In contrast, SCs exhibit low EGR2 expression during Wallerian degeneration after injury. In this study, we screened 10 potential microRNAs (miRNAs) (20a-5p, 137-5p, 140-5p, 148b-3p, 150-5p, 17-5p, 93-5p, 20b-5p, 106b-5p, and 152-3p) that potentially target EGR2 using miRNA algorithms and identified that miRNAs 106b-5p, 140-5p, 93-5p, and 17-5p target EGR2 in SCs. These miRNAs directly target EGR2 by binding to the 3'-untranslated region to suppress EGR2 mRNA levels. Additionally, the levels of miRNAs 93-5p, 106b-5p, 17-5p, and 140-5p were decreased in the sciatic nerves during postnatal development; however, these miRNAs were increased on day 1 after sciatic nerve injury. Taken together, these findings suggest that the expression of EGR2 during postnatal development and Wallerian degeneration could be regulated by the inverse expression of miRNAs 106b-5p, 140-5p, 93-5p, and 17-5p, which target EGR2.
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19
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Graf SA, Heppt MV, Wessely A, Krebs S, Kammerbauer C, Hornig E, Strieder A, Blum H, Bosserhoff AK, Berking C. The myelin protein PMP2 is regulated by SOX10 and drives melanoma cell invasion. Pigment Cell Melanoma Res 2018; 32:424-434. [PMID: 30506895 DOI: 10.1111/pcmr.12760] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 10/05/2018] [Accepted: 11/20/2018] [Indexed: 12/22/2022]
Abstract
The transcription factor sex determining region Y-box 10 (SOX10) plays a key role in the development of melanocytes and glial cells from neural crest precursors. SOX10 is involved in melanoma initiation, proliferation, invasion, and survival. However, specific mediators which impart its oncogenic properties remain widely unknown. To identify target genes of SOX10, we performed RNA sequencing after ectopic expression of SOX10 in human melanoma cells. Among nine differentially regulated genes, peripheral myelin protein 2 (PMP2) was consistently upregulated in several cell lines. Direct regulation of PMP2 by SOX10 was shown by chromatin immunoprecipitation, electrophoretic mobility shift, and luciferase reporter assays. Moreover, a coregulation of PMP2 by SOX10 and early growth response 2 in melanoma cells was found. Phenotypical investigation demonstrated that PMP2 expression can increase melanoma cell invasion. As PMP2 protein was detected only in a subset of melanoma cell lines, it might contribute to melanoma heterogeneity.
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Affiliation(s)
- Saskia Anna Graf
- Department of Dermatology and Allergy, University Hospital, LMU Munich, Munich, Germany
| | - Markus Vincent Heppt
- Department of Dermatology and Allergy, University Hospital, LMU Munich, Munich, Germany
| | - Anja Wessely
- Department of Dermatology and Allergy, University Hospital, LMU Munich, Munich, Germany
| | - Stefan Krebs
- Gene Center, Ludwig-Maximilian University of Munich, Munich, Germany
| | - Claudia Kammerbauer
- Department of Dermatology and Allergy, University Hospital, LMU Munich, Munich, Germany
| | - Eva Hornig
- Department of Dermatology and Allergy, University Hospital, LMU Munich, Munich, Germany
| | - Annamarie Strieder
- Department of Dermatology and Allergy, University Hospital, LMU Munich, Munich, Germany
| | - Helmut Blum
- Gene Center, Ludwig-Maximilian University of Munich, Munich, Germany
| | - Anja-Katrin Bosserhoff
- Department of Biochemistry and Molecular Medicine, Institute of Biochemistry, Emil Fischer Center, University of Erlangen-Nürnberg, Erlangen, Germany.,Comprehensive Cancer Center (CCC) Erlangen-EMN, Erlangen, Germany
| | - Carola Berking
- Department of Dermatology and Allergy, University Hospital, LMU Munich, Munich, Germany
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20
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Rosenberg LH, Cattin AL, Fontana X, Harford-Wright E, Burden JJ, White IJ, Smith JG, Napoli I, Quereda V, Policarpi C, Freeman J, Ketteler R, Riccio A, Lloyd AC. HDAC3 Regulates the Transition to the Homeostatic Myelinating Schwann Cell State. Cell Rep 2018; 25:2755-2765.e5. [PMID: 30517863 PMCID: PMC6293966 DOI: 10.1016/j.celrep.2018.11.045] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Revised: 10/16/2018] [Accepted: 11/09/2018] [Indexed: 12/29/2022] Open
Abstract
The formation of myelinating Schwann cells (mSCs) involves the remarkable biogenic process, which rapidly generates the myelin sheath. Once formed, the mSC transitions to a stable homeostatic state, with loss of this stability associated with neuropathies. The histone deacetylases histone deacetylase 1 (HDAC1) and HDAC2 are required for the myelination transcriptional program. Here, we show a distinct role for HDAC3, in that, while dispensable for the formation of mSCs, it is essential for the stability of the myelin sheath once formed-with loss resulting in progressive severe neuropathy in adulthood. This is associated with the prior failure to downregulate the biogenic program upon entering the homeostatic state leading to hypertrophy and hypermyelination of the mSCs, progressing to the development of severe myelination defects. Our results highlight distinct roles of HDAC1/2 and HDAC3 in controlling the differentiation and homeostatic states of a cell with broad implications for the understanding of this important cell-state transition.
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Affiliation(s)
- Laura H Rosenberg
- MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK; CRUK Therapeutic Discovery Laboratories, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Anne-Laure Cattin
- MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Xavier Fontana
- MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Elizabeth Harford-Wright
- MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Jemima J Burden
- MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Ian J White
- MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Jacob G Smith
- MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Ilaria Napoli
- MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Victor Quereda
- MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK; The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA
| | - Cristina Policarpi
- MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Jamie Freeman
- MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK; Horizon Discovery, 8100 Cambridge Research Park, Cambridge CB25 9TL, UK
| | - Robin Ketteler
- MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Antonella Riccio
- MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Alison C Lloyd
- MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK; UCL Cancer Institute, University College London, Gower Street, London WC1E 6BT, UK.
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21
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LaVallee J, Grant T, D'Angelo-Early S, Kletsov S, Berry NA, Abt KM, Bloch CP, Muscedere ML, Adams KW. Refining the nuclear localization signal within the Egr transcriptional coregulator NAB2. FEBS Lett 2018; 593:107-118. [PMID: 30411343 DOI: 10.1002/1873-3468.13288] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 10/29/2018] [Accepted: 11/02/2018] [Indexed: 01/09/2023]
Abstract
NAB1 and 2 are coregulators for early growth response (Egr) transcription factors. The NAB1 nuclear localization signal (NLS) was previously described as a bipartite NLS of sequence R(X2 )K(X11 )KRXK. The sequence is conserved in NAB2 as K(X2 )R(X11 )KKXK; however, whether it functions as the NAB2 NLS has not been tested. We show that the KKXK motif in NAB2 is necessary and sufficient to mediate nuclear localization. Mutation of the KKXK motif to AAXA causes cytoplasmic localization of NAB2, while Lys/Arg-to-Ala mutations of the upstream K(X2 )R motif have no effect. Fusion of the KKXK motif to cytoplasmic protein eIF2Bε causes nuclear localization. Altogether, this study refines our knowledge of the NAB2 NLS, demonstrating that KKXK343-346 is necessary and sufficient for nuclear localization.
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Affiliation(s)
- Jacquelyn LaVallee
- Department of Biological Sciences, Bridgewater State University, Bridgewater, MA, USA
| | - Terrain Grant
- Department of Biological Sciences, Bridgewater State University, Bridgewater, MA, USA
| | | | - Sergey Kletsov
- Department of Biological Sciences, Bridgewater State University, Bridgewater, MA, USA
| | - Nicole A Berry
- Department of Biological Sciences, Bridgewater State University, Bridgewater, MA, USA
| | - Kimberly M Abt
- Department of Biological Sciences, Bridgewater State University, Bridgewater, MA, USA
| | - Christopher P Bloch
- Department of Biological Sciences, Bridgewater State University, Bridgewater, MA, USA
| | | | - Kenneth W Adams
- Department of Biological Sciences, Bridgewater State University, Bridgewater, MA, USA
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22
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Zhang D, Wu S, Feng J, Duan Y, Xing D, Gao C. Micropatterned biodegradable polyesters clicked with CQAASIKVAV promote cell alignment, directional migration, and neurite outgrowth. Acta Biomater 2018; 74:143-155. [PMID: 29768188 DOI: 10.1016/j.actbio.2018.05.018] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2018] [Revised: 03/28/2018] [Accepted: 05/11/2018] [Indexed: 12/31/2022]
Abstract
The interplay of microstructures and biological cues is critical to regulate the behaviors of Schwann cells (SCs) in terms of cellular spatial arrangement and directional migration as well as neurite orientation for bridging the proximal and distal stumps of the injured peripheral nervous system. In this study, stripe micropatterns having ridges/grooves of width 20/20 and 20/40 μm were fabricated on the surface of maleimide-functionalized biodegradable poly(ester carbonate) (P(LLA-MTMC)) films by the polydimethylsiloxane mold-pressing method, respectively. The laminin-derived CQAASIKVAV peptides end-capped with an SH group were then grafted by the thiol-ene click reaction under mild conditions to obtain micropatterned and peptide-grafted films. SCs cultured on these films, especially on the 20/40-μm film, displayed faster and aligned adhesion as well as a larger number of elongated cells with a higher length-to-width (L/W) ratio along the stripe direction than those on the flat-pep film. The migration rate of SCs was significantly enhanced in parallel to the stripe direction with a large net displacement. The micropatterned and peptide-grafted films, especially the 20/40-μm film, could promote SC proliferation and nerve growth factor (NGF) secretion in a manner similar to that of the peptide-grafted planar film. Moreover, the neurites of rat pheochromocytoma 12 (PC12) cells sprouted along the ridges with a longer average length on the micropatterned and peptide-grafted films. The synergistic effect of physical patterns and biological cues was evaluated by considering the results of cell adhesion force; immunofluorescence staining of vinculin; fluorescence staining of F-actin and the nucleus; as well as gene expression of neural cadherin (NCAD), neurocan (NCAN), and myelin protein zero (P0). STATEMENT OF SIGNIFICANCE The interplay of microstructures and biological cues is critical to regulate the behaviors of Schwann cells (SCs) and nerve cells, and thereby the regeneration of peripheral nerve system. In this study, the combined micropatterning and CQAASIKVAV grafting endowed the modified P(LLA-MTMC) films with both contact guidance and bioactive chemical cues to enhance cell proliferation, directional alignment and migration, longer net displacement and larger NGF secretion, and stronger neurite outgrowth of SCs and PC12 cells. Hence, the integration of physical micropatterns and bioactive molecules is an effective way to obtain featured biomaterials for the regeneration of nerves and other types of tissues.
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23
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DHTKD1 Deficiency Causes Charcot-Marie-Tooth Disease in Mice. Mol Cell Biol 2018; 38:MCB.00085-18. [PMID: 29661920 DOI: 10.1128/mcb.00085-18] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 04/08/2018] [Indexed: 01/20/2023] Open
Abstract
DHTKD1, a part of 2-ketoadipic acid dehydrogenase complex, is involved in lysine and tryptophan catabolism. Mutations in DHTKD1 block the metabolic pathway and cause 2-aminoadipic and 2-oxoadipic aciduria (AMOXAD), an autosomal recessive inborn metabolic disorder. In addition, a nonsense mutation in DHTKD1 that we identified previously causes Charcot-Marie-Tooth disease (CMT) type 2Q, one of the most common inherited neurological disorders affecting the peripheral nerves in the musculature. However, the comprehensive molecular mechanism underlying CMT2Q remains elusive. Here, we show that Dhtkd1-/- mice mimic the major aspects of CMT2 phenotypes, characterized by progressive weakness and atrophy in the distal parts of limbs with motor and sensory dysfunctions, which are accompanied with decreased nerve conduction velocity. Moreover, DHTKD1 deficiency causes severe metabolic abnormalities and dramatically increased levels of 2-ketoadipic acid (2-KAA) and 2-aminoadipic acid (2-AAA) in urine. Further studies revealed that both 2-KAA and 2-AAA could stimulate insulin biosynthesis and secretion. Subsequently, elevated insulin regulates myelin protein zero (Mpz) transcription in Schwann cells via upregulating the expression of early growth response 2 (Egr2), leading to myelin structure damage and axonal degeneration. Finally, 2-AAA-fed mice do reproduce phenotypes similar to CMT2Q phenotypes. In conclusion, we have demonstrated that loss of DHTKD1 causes CMT2Q-like phenotypes through dysregulation of Mpz mRNA and protein zero (P0) which are closely associated with elevated DHTKD1 substrate and insulin levels. These findings further indicate an important role of metabolic disorders in addition to mitochondrial insufficiency in the pathogenesis of peripheral neuropathies.
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Evaluation of Epigallocatechin-3-gallate Modified Collagen Membrane and Concerns on Schwann Cells. BIOMED RESEARCH INTERNATIONAL 2017; 2017:9641801. [PMID: 28894753 PMCID: PMC5574217 DOI: 10.1155/2017/9641801] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 06/05/2017] [Accepted: 07/05/2017] [Indexed: 02/05/2023]
Abstract
Collagen is an essential component of the extracellular matrix (ECM) and is a suitable material for nerve repair during tissue remodeling for fracture repair. Epigallocatechin-3-gallate (EGCG), an extract of green tea, shows various biological activities that are beneficial to nerve repair. Here, we developed modified collagen containing different concentrations of EGCG (0.0064%, 0.064%, and 0.64%, resp.) to induce Schwann cell proliferation and differentiation. Cell Counting Kit-8 test, live/dead assay, and SEM showed that collagen cross-linked by EGCG induced Schwann cell proliferation. Real-time polymerase chain reaction, enzyme-linked immunosorbent assay, and Western blotting revealed that EGCG-modified collagen induced Schwann cell differentiation and downregulated reactive oxygen species (ROS) levels by downregulating the MAPK P38 signaling pathway. Our results indicate that collagen cross-linked with an appropriate concentration of EGCG induces the proliferation and differentiation of Schwann cells. The EGCG-modified collagen membrane may be applicable for nerve repair and guided tissue regeneration applications.
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Adams KW, Kletsov S, Lamm RJ, Elman JS, Mullenbrock S, Cooper GM. Role for Egr1 in the Transcriptional Program Associated with Neuronal Differentiation of PC12 Cells. PLoS One 2017; 12:e0170076. [PMID: 28076410 PMCID: PMC5226839 DOI: 10.1371/journal.pone.0170076] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 12/28/2016] [Indexed: 11/17/2022] Open
Abstract
PC12 cells are a well-established model to study how differences in signal transduction duration can elicit distinct cell behaviors. Epidermal growth factor (EGF) activates transient ERK signaling in PC12 cells that lasts 30–60 min, which in turn promotes proliferation; nerve growth factor (NGF) activates more sustained ERK signaling that lasts 4–6 h, which in turns induces neuronal differentiation. Data presented here extend a previous study by Mullenbrock et al. (2011) that demonstrated that sustained ERK signaling in response to NGF induces preferential expression of a 69-member gene set compared to transient ERK signaling in response to EGF and that the transcription factors AP-1 and CREB play a major role in the preferential expression of several genes within the set. Here, we examined whether the Egr family of transcription factors also contributes to the preferential expression of the gene set in response to NGF. Our data demonstrate that NGF causes transient induction of all Egr family member transcripts, but a corresponding induction of protein was detected for only Egr1 and 2. Chromatin immunoprecipitation experiments provided clearest evidence that, after induction, Egr1 binds 12 of the 69 genes that are preferentially expressed during sustained ERK signaling. In addition, Egr1 expression and binding upstream of its target genes were both sustained in response to NGF versus EGF within the same timeframe that its targets are preferentially expressed. These data thus provide evidence that Egr1 contributes to the transcriptional program activated by sustained ERK signaling in response to NGF, specifically by contributing to the preferential expression of its target genes identified here.
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Affiliation(s)
- Kenneth W Adams
- Department of Biological Sciences, Bridgewater State University, Bridgewater, Massachusetts, United States of America
| | - Sergey Kletsov
- Department of Biological Sciences, Bridgewater State University, Bridgewater, Massachusetts, United States of America
| | - Ryan J Lamm
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
| | - Jessica S Elman
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
| | - Steven Mullenbrock
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
| | - Geoffrey M Cooper
- Department of Biology, Boston University, Boston, Massachusetts, United States of America
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Gopinath C, Law WD, Rodríguez-Molina JF, Prasad AB, Song L, Crawford GE, Mullikin JC, Svaren J, Antonellis A. Stringent comparative sequence analysis reveals SOX10 as a putative inhibitor of glial cell differentiation. BMC Genomics 2016; 17:887. [PMID: 27821050 PMCID: PMC5100263 DOI: 10.1186/s12864-016-3167-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 10/18/2016] [Indexed: 01/22/2023] Open
Abstract
Background The transcription factor SOX10 is essential for all stages of Schwann cell development including myelination. SOX10 cooperates with other transcription factors to activate the expression of key myelin genes in Schwann cells and is therefore a context-dependent, pro-myelination transcription factor. As such, the identification of genes regulated by SOX10 will provide insight into Schwann cell biology and related diseases. While genome-wide studies have successfully revealed SOX10 target genes, these efforts mainly focused on myelinating stages of Schwann cell development. We propose that less-biased approaches will reveal novel functions of SOX10 outside of myelination. Results We developed a stringent, computational-based screen for genome-wide identification of SOX10 response elements. Experimental validation of a pilot set of predicted binding sites in multiple systems revealed that SOX10 directly regulates a previously unreported alternative promoter at SOX6, which encodes a transcription factor that inhibits glial cell differentiation. We further explored the utility of our computational approach by combining it with DNase-seq analysis in cultured Schwann cells and previously published SOX10 ChIP-seq data from rat sciatic nerve. Remarkably, this analysis enriched for genomic segments that map to loci involved in the negative regulation of gliogenesis including SOX5, SOX6, NOTCH1, HMGA2, HES1, MYCN, ID4, and ID2. Functional studies in Schwann cells revealed that: (1) all eight loci are expressed prior to myelination and down-regulated subsequent to myelination; (2) seven of the eight loci harbor validated SOX10 binding sites; and (3) seven of the eight loci are down-regulated upon repressing SOX10 function. Conclusions Our computational strategy revealed a putative novel function for SOX10 in Schwann cells, which suggests a model where SOX10 activates the expression of genes that inhibit myelination during non-myelinating stages of Schwann cell development. Importantly, the computational and functional datasets we present here will be valuable for the study of transcriptional regulation, SOX protein function, and glial cell biology. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-3167-3) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Chetna Gopinath
- Cellular and Molecular Biology Program, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - William D Law
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI, 48109, USA
| | - José F Rodríguez-Molina
- Cellular and Molecular Pathology Program, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Arjun B Prasad
- Genome Technology Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Lingyun Song
- Center for Genomic and Computational Biology, Duke University Medical Center, Durham, NC, 27708, USA
| | - Gregory E Crawford
- Center for Genomic and Computational Biology, Duke University Medical Center, Durham, NC, 27708, USA.,Department of Pediatrics, Duke University Medical Center, Durham, NC, 27708, USA
| | - James C Mullikin
- Genome Technology Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - John Svaren
- Waisman Center, University of Wisconsin-Madison, Madison, WI, 53706, USA.,Department of Comparative Biosciences, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Anthony Antonellis
- Cellular and Molecular Biology Program, University of Michigan Medical School, Ann Arbor, MI, 48109, USA. .,Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI, 48109, USA. .,Department of Neurology, University of Michigan Medical School, Ann Arbor, MI, 48109, USA.
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Optimal myelin elongation relies on YAP activation by axonal growth and inhibition by Crb3/Hippo pathway. Nat Commun 2016; 7:12186. [PMID: 27435623 PMCID: PMC4961766 DOI: 10.1038/ncomms12186] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 06/09/2016] [Indexed: 01/24/2023] Open
Abstract
Fast nerve conduction relies on successive myelin segments that electrically isolate axons. Segment geometry—diameter and length—is critical for the optimization of nerve conduction and the molecular mechanisms allowing this optimized geometry are partially known. We show here that peripheral myelin elongation is dynamically regulated by stimulation of YAP (Yes-associated protein) transcription cofactor activity during axonal elongation and limited by inhibition of YAP activity via the Hippo pathway. YAP promotes myelin and non-myelin genes transcription while the polarity protein Crb3, localized at the tips of the myelin sheath, activates the Hippo pathway to temper YAP activity, therefore allowing for optimal myelin growth. Dystrophic Dy2j/2j mice mimicking human peripheral neuropathy with reduced internodal lengths have decreased nuclear YAP which, when corrected, leads to longer internodes. These data show a novel mechanism controlling myelin growth and nerve conduction, and provide a molecular ground for disease with short myelin segments. Molecular mechanisms regulating optimal myelin geometry are only partially understood. Here authors show that peripheral myelin growth is orchestrated by the Crb3/Hippo/YAP pathway, and that defects in YAP activation may underlie peripheral neuropathies caused by shorter myelin.
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28
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Lopez-Anido C, Sun G, Koenning M, Srinivasan R, Hung HA, Emery B, Keles S, Svaren J. Differential Sox10 genomic occupancy in myelinating glia. Glia 2015; 63:1897-1914. [PMID: 25974668 PMCID: PMC4644515 DOI: 10.1002/glia.22855] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 04/22/2015] [Indexed: 11/11/2022]
Abstract
Myelin is formed by specialized myelinating glia: oligodendrocytes and Schwann cells in the central and peripheral nervous systems, respectively. While there are distinct developmental aspects and regulatory pathways in these two cell types, myelination in both systems requires the transcriptional activator Sox10. Sox10 interacts with cell type-specific transcription factors at some loci to induce myelin gene expression, but it is largely unknown how Sox10 transcriptional networks globally compare between oligodendrocytes and Schwann cells. We used in vivo ChIP-Seq analysis of spinal cord and peripheral nerve (sciatic nerve) to identify unique and shared Sox10 binding sites and assess their correlation with active enhancers and transcriptional profiles in oligodendrocytes and Schwann cells. Sox10 binding sites overlap with active enhancers and critical cell type-specific regulators of myelination, such as Olig2 and Myrf in oligodendrocytes, and Egr2/Krox20 in Schwann cells. Sox10 sites also associate with genes critical for myelination in both oligodendrocytes and Schwann cells and are found within super-enhancers previously defined in brain. In Schwann cells, Sox10 sites contain binding motifs of putative partners in the Sp/Klf, Tead, and nuclear receptor protein families. Specifically, siRNA analysis of nuclear receptors Nr2f1 and Nr2f2 revealed downregulation of myelin genes Mbp and Ndrg1 in primary Schwann cells. Our analysis highlights different mechanisms that establish cell type-specific genomic occupancy of Sox10, which reflects the unique characteristics of oligodendrocyte and Schwann cell differentiation. GLIA 2015;63:1897-1914.
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Affiliation(s)
- Camila Lopez-Anido
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
- Comparative Biomedical Sciences Graduate Program, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Guannan Sun
- Department of Biostatistics & Medical Informatics, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Matthias Koenning
- Department of Anatomy and Neuroscience and the Centre for Neuroscience Research, University of Melbourne, Melbourne, Australia
| | - Rajini Srinivasan
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Holly A. Hung
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA
- Cellular and Molecular Pathology Graduate Program, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Ben Emery
- Department of Anatomy and Neuroscience and the Centre for Neuroscience Research, University of Melbourne, Melbourne, Australia
| | - Sunduz Keles
- Cellular and Molecular Pathology Graduate Program, 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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29
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Stolt CC, Wegner M. Schwann cells and their transcriptional network: Evolution of key regulators of peripheral myelination. Brain Res 2015; 1641:101-110. [PMID: 26423937 DOI: 10.1016/j.brainres.2015.09.025] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Revised: 09/18/2015] [Accepted: 09/20/2015] [Indexed: 11/29/2022]
Abstract
As derivatives of the neural crest, Schwann cells represent a vertebrate invention. Their development and differentiation is under control of a newly constructed, vertebrate-specific regulatory network that contains Sox10, Oct6 and Krox20 as cornerstones and central regulators of peripheral myelination. In this review, we discuss the function and relationship of these transcription factors among each other and in the context of their regulatory network, and present ideas of how neofunctionalization may have helped to recruit them to their novel task in Schwann cells. This article is part of a Special Issue entitled SI: Myelin Evolution.
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Affiliation(s)
- C Claus Stolt
- Institut für Biochemie, Emil-Fischer-Zentrum, Friedrich-Alexander-Universität Erlangen-Nürnberg, D-91054 Erlangen, Germany
| | - Michael Wegner
- Institut für Biochemie, Emil-Fischer-Zentrum, Friedrich-Alexander-Universität Erlangen-Nürnberg, D-91054 Erlangen, Germany.
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30
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Patzig J, Kusch K, Fledrich R, Eichel MA, Lüders KA, Möbius W, Sereda MW, Nave KA, Martini R, Werner HB. Proteolipid protein modulates preservation of peripheral axons and premature death when myelin protein zero is lacking. Glia 2015; 64:155-74. [PMID: 26393339 DOI: 10.1002/glia.22922] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 09/04/2015] [Indexed: 12/23/2022]
Abstract
Protein zero (P0) is the major structural component of peripheral myelin. Lack of this adhesion protein from Schwann cells causes a severe dysmyelinating neuropathy with secondary axonal degeneration in humans with the neuropathy Dejerine-Sottas syndrome (DSS) and in the corresponding mouse model (P0(null)-mice). In the mammalian CNS, the tetraspan-membrane protein PLP is the major structural myelin constituent and required for the long-term preservation of myelinated axons, which fails in hereditary spastic paraplegia (SPG type-2) and the relevant mouse model (Plp(null)-mice). The Plp-gene is also expressed in Schwann cells but PLP is of very low abundance in normal peripheral myelin; its function has thus remained enigmatic. Here we show that the abundance of PLP but not of other tetraspan myelin proteins is strongly increased in compact peripheral myelin of P0(null)-mice. To determine the functional relevance of PLP expression in the absence of P0, we generated P0(null)*Plp(null)-double-mutant mice. Compared with either single-mutant, P0(null)*Plp(null)-mice display impaired nerve conduction, reduced motor functions, and premature death. At the morphological level, axonal segments were frequently non-myelinated but in a one-to-one relationship with a hypertrophic Schwann cell. Importantly, axonal numbers were reduced in the vital phrenic nerve of P0(null)*Plp(null)-mice. In the absence of P0, thus, PLP also contributes to myelination by Schwann cells and to the preservation of peripheral axons. These data provide a link between the Schwann cell-dependent support of peripheral axons and the oligodendrocyte-dependent support of central axons.
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Affiliation(s)
- Julia Patzig
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Kathrin Kusch
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Robert Fledrich
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Maria A Eichel
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Katja A Lüders
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Wiebke Möbius
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany.,Center for Nanoscale Microscopy and Molecular Physiology of the Brain, Göttingen, Germany
| | - Michael W Sereda
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany.,Department of Clinical Neurophysiology, University Medical Center, Göttingen, Germany
| | - Klaus-Armin Nave
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Rudolf Martini
- Department of Neurology, Developmental Neurobiology, University Hospital, Würzburg, Germany
| | - Hauke B Werner
- Department of Neurogenetics, Max Planck Institute of Experimental Medicine, Göttingen, Germany
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31
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Lin HP, Oksuz I, Hurley E, Wrabetz L, Awatramani R. Microprocessor complex subunit DiGeorge syndrome critical region gene 8 (Dgcr8) is required for schwann cell myelination and myelin maintenance. J Biol Chem 2015; 290:24294-307. [PMID: 26272614 DOI: 10.1074/jbc.m115.636407] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Indexed: 01/25/2023] Open
Abstract
We investigated the role of a key component of the Microprocessor complex, DGCR8, in the regulation of myelin formation and maintenance. We found that conditionally ablating Dgcr8 in Schwann cells (SCs) during development results in an arrest of SC differentiation. Dgcr8 conditional knock-out (cKO) SCs fail to form 1:1 relationships with axons or, having achieved this, fail to form myelin sheaths. The expression of genes normally found in immature SCs, such as sex-determining region Y-box 2 (Sox2), is increased in Dgcr8 cKO SCs, whereas the expression of myelin-related genes, including the master regulatory transcription factor early growth response 2 (Egr2), is decreased. Additionally, expression of a novel gene expression program involving sonic hedgehog (Shh), activated de novo in injured nerves, is elevated in Dgcr8 cKOs but not in Egr2 null mice, a model of SC differentiation arrest, suggesting that the injury-related gene expression program in Dgcr8 cKOs cannot be attributed to differentiation arrest. Inducible ablation of Dgcr8 in adult SCs results in gene expression changes similar to those found in cKOs, including an increase in the expression of Sox2 and Shh. Analyses of these nerves mainly reveal normal myelin thickness and axon size distribution but some dedifferentiated SCs and increased macrophage infiltration. Together our data suggest that Dgcr8 is responsible for modulation of gene expression programs underlying myelin formation and maintenance as well as suppression of an injury-related gene expression program.
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Affiliation(s)
- Hsin-Pin Lin
- From the Department of Neurology and Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611 and
| | - Idil Oksuz
- From the Department of Neurology and Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611 and
| | - Edward Hurley
- Hunter James Kelly Research Institute, University at Buffalo, State University of New York, Buffalo, New York 14203
| | - Lawrence Wrabetz
- Hunter James Kelly Research Institute, University at Buffalo, State University of New York, Buffalo, New York 14203
| | - Rajeshwar Awatramani
- From the Department of Neurology and Center for Genetic Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611 and
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32
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Chen Z, Yue SX, Zhou G, Greenfield EM, Murakami S. ERK1 and ERK2 regulate chondrocyte terminal differentiation during endochondral bone formation. J Bone Miner Res 2015; 30:765-74. [PMID: 25401279 PMCID: PMC4487783 DOI: 10.1002/jbmr.2409] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Revised: 11/06/2014] [Accepted: 11/12/2014] [Indexed: 12/29/2022]
Abstract
Chondrocytes in the epiphyseal cartilage undergo terminal differentiation prior to their removal through apoptosis. To examine the role of ERK1 and ERK2 in chondrocyte terminal differentiation, we generated Osterix (Osx)-Cre; ERK1(-/-) ; ERK2(flox/flox) mice (conditional knockout Osx [cKOosx]), in which ERK1 and ERK2 were deleted in hypertrophic chondrocytes. These cKOosx mice were grossly normal in size at birth, but by 3 weeks of age exhibited shorter long bones. Histological analysis in these mice revealed that the zone of hypertrophic chondrocytes in the growth plate was markedly expanded. In situ hybridization and quantitative real-time PCR analyses demonstrated that Matrix metalloproteinase-13 (Mmp13) and Osteopontin expression was significantly decreased, indicating impaired chondrocyte terminal differentiation. Moreover, Egr1 and Egr2, transcription factors whose expression is restricted to the last layers of hypertrophic chondrocytes in wild-type mice, were also strongly downregulated in these cKOosx mice. In transient transfection experiments in the RCS rat chondrosarcoma cell line, the expression of Egr1, Egr2, or a constitutively active mutant of MEK1 increased the activity of an Osteopontin promoter, whereas the MEK1-induced activation of the Osteopontin promoter was inhibited by the coexpression of Nab2, an Egr1 and Egr2 co-repressor. These results suggest that MEK1-ERK signaling activates the Osteopontin promoter in part through Egr1 and Egr2. Finally, our histological analysis of cKOosx mice demonstrated enchondroma-like lesions in the bone marrow that are reminiscent of human metachondromatosis, a skeletal disorder caused by mutations in PTPN11. Our observations suggest that the development of enchondromas in metachondromatosis may be caused by reduced extracellular signal-regulated kinase/mitogen-activated protein kinase (ERK MAPK) signaling.
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Affiliation(s)
- Zhijun Chen
- Department of Orthopaedics, Case Western Reserve University, Cleveland, Ohio 44106
| | - Susan X. Yue
- Department of Orthopaedics, Case Western Reserve University, Cleveland, Ohio 44106
| | - Guang Zhou
- Department of Orthopaedics, Case Western Reserve University, Cleveland, Ohio 44106
- Department of Genetics and Genomic Sciences, Case Western Reserve University, Cleveland, Ohio 44106
| | - Edward M. Greenfield
- Department of Orthopaedics, Case Western Reserve University, Cleveland, Ohio 44106
- Division of General Medical Sciences, National Center for Regenerative Medicine, Case Western Reserve University, Cleveland, Ohio 44106
| | - Shunichi Murakami
- Department of Orthopaedics, Case Western Reserve University, Cleveland, Ohio 44106
- Department of Genetics and Genomic Sciences, Case Western Reserve University, Cleveland, Ohio 44106
- Division of General Medical Sciences, National Center for Regenerative Medicine, Case Western Reserve University, Cleveland, Ohio 44106
- Murakami Geka Iin, Kawasaki, 210-0834 Japan
- Corresponding author: Shunichi Murakami, 11100 Euclid Avenue, Hanna House 6th floor, Cleveland, Ohio 44106, phone: 216-368-3965, fax: 216-368-1332,
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Hung HA, Sun G, Keles S, Svaren J. Dynamic regulation of Schwann cell enhancers after peripheral nerve injury. J Biol Chem 2015; 290:6937-50. [PMID: 25614629 PMCID: PMC4358118 DOI: 10.1074/jbc.m114.622878] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Revised: 12/31/2014] [Indexed: 12/20/2022] Open
Abstract
Myelination of the peripheral nervous system is required for axonal function and long term stability. After peripheral nerve injury, Schwann cells transition from axon myelination to a demyelinated state that supports neuronal survival and ultimately remyelination of axons. Reprogramming of gene expression patterns during development and injury responses is shaped by the actions of distal regulatory elements that integrate the actions of multiple transcription factors. We used ChIP-seq to measure changes in histone H3K27 acetylation, a mark of active enhancers, to identify enhancers in myelinating rat peripheral nerve and their dynamics after demyelinating nerve injury. Analysis of injury-induced enhancers identified enriched motifs for c-Jun, a transcription factor required for Schwann cells to support nerve regeneration. We identify a c-Jun-bound enhancer in the gene for Runx2, a transcription factor induced after nerve injury, and we show that Runx2 is required for activation of other induced genes. In contrast, enhancers that lose H3K27ac after nerve injury are enriched for binding sites of the Sox10 and early growth response 2 (Egr2/Krox20) transcription factors, which are critical determinants of Schwann cell differentiation. Egr2 expression is lost after nerve injury, and many Egr2-binding sites lose H3K27ac after nerve injury. However, the majority of Egr2-bound enhancers retain H3K27ac, indicating that other transcription factors maintain active enhancer status after nerve injury. The global epigenomic changes in H3K27ac deposition pinpoint dynamic changes in enhancers that mediate the effects of transcription factors that control Schwann cell myelination and peripheral nervous system responses to nerve injury.
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Affiliation(s)
- Holly A Hung
- From the Waisman Center, Cellular and Molecular Pathology Graduate Program, and
| | - Guannan Sun
- Departments of Biostatistics and Medical Informatics and
| | - Sunduz Keles
- Departments of Biostatistics and Medical Informatics and
| | - John Svaren
- From the Waisman Center, Comparative Biosciences, University of Wisconsin-Madison, Madison, Wisconsin 53705
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34
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Jacob C. Transcriptional control of neural crest specification into peripheral glia. Glia 2015; 63:1883-1896. [PMID: 25752517 DOI: 10.1002/glia.22816] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 01/29/2015] [Accepted: 02/20/2015] [Indexed: 12/20/2022]
Abstract
The neural crest is a transient migratory multipotent cell population that originates from the neural plate border and is formed at the end of gastrulation and during neurulation in vertebrate embryos. These cells give rise to many different cell types of the body such as chondrocytes, smooth muscle cells, endocrine cells, melanocytes, and cells of the peripheral nervous system including different subtypes of neurons and peripheral glia. Acquisition of lineage-specific markers occurs before or during migration and/or at final destination. What are the mechanisms that direct specification of neural crest cells into a specific lineage and how do neural crest cells decide on a specific migration route? Those are fascinating and complex questions that have existed for decades and are still in the research focus of developmental biologists. This review discusses transcriptional events and regulations occurring in neural crest cells and derived lineages, which control specification of peripheral glia, namely Schwann cell precursors that interact with peripheral axons and further differentiate into myelinating or nonmyelinating Schwann cells, satellite cells that remain tightly associated with neuronal cell bodies in sensory and autonomous ganglia, and olfactory ensheathing cells that wrap olfactory axons, both at the periphery in the olfactory mucosa and in the central nervous system in the olfactory bulb. Markers of the different peripheral glia lineages including intermediate multipotent cells such as boundary cap cells, as well as the functions of these specific markers, are also reviewed. Enteric ganglia, another type of peripheral glia, will not be discussed in this review. GLIA 2015;63:1883-1896.
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Affiliation(s)
- Claire Jacob
- Department of Biology, University of Fribourg, Fribourg, Switzerland
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Svaren J. MicroRNA and transcriptional crosstalk in myelinating glia. Neurochem Int 2014; 77:50-7. [PMID: 24979526 PMCID: PMC4177339 DOI: 10.1016/j.neuint.2014.06.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Revised: 06/10/2014] [Accepted: 06/17/2014] [Indexed: 12/21/2022]
Abstract
Several recent studies have addressed the important role of microRNA in regulation of differentiation of myelinating glia. While Schwann cells and oligodendrocytes in the peripheral and central nervous systems, respectively, exhibit significant morphological and regulatory differences, some aspects of transcriptional and microRNA regulation are shared between these two cell types. This review focuses on the intersection of microRNAs with transcriptional regulation in Schwann cell and oligodendrocyte differentiation. In particular, several microRNAs have been shown to modulate expression of critical transcription factors, and in turn, the regulation of microRNA expression is enmeshed within transcriptional networks that coordinate both coding gene and noncoding RNA profiles of myelinating cells. These hubs of regulation control both myelin gene expression as well as the cell cycle transitions of Schwann cells and oligodendrocytes as they terminally differentiate. In addition, some studies have begin to highlight the combinatorial effects of different microRNAs that establish the narrow range of gene regulation required for efficient and stable myelin formation. Overall, the integration of microRNA and transcriptional aspects will help elucidate mechanistic control of the myelination process.
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Affiliation(s)
- John Svaren
- Department of Comparative Biosciences and Waisman Center, University of Wisconsin-Madison, 1500 Highland Ave., Madison, WI 53705, USA.
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Mitew S, Hay C, Peckham H, Xiao J, Koenning M, Emery B. Mechanisms regulating the development of oligodendrocytes and central nervous system myelin. Neuroscience 2014; 276:29-47. [DOI: 10.1016/j.neuroscience.2013.11.029] [Citation(s) in RCA: 154] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2013] [Revised: 11/13/2013] [Accepted: 11/14/2013] [Indexed: 12/29/2022]
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Uggenti C, De Stefano ME, Costantino M, Loreti S, Pisano A, Avallone B, Talora C, Magnaghi V, Tata AM. M2 muscarinic receptor activation regulates Schwann cell differentiation and myelin organization. Dev Neurobiol 2014; 74:676-91. [PMID: 24403178 DOI: 10.1002/dneu.22161] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Revised: 12/14/2013] [Accepted: 12/15/2013] [Indexed: 01/01/2023]
Abstract
Glial cells express acetylcholine receptors. In particular, rat Schwann cells express different muscarinic receptor subtypes, the most abundant of which is the M2 subtype. M2 receptor activation causes a reversible arrest of the cell cycle. This negative effect on Schwann cell proliferation suggests that these cells may possibly progress into a differentiating program. In this study we analyzed the in vitro modulation, by the M2 agonist arecaidine, of transcription factors and specific signaling pathways involved in Schwann cell differentiation. The arecaidine-induced M2 receptor activation significantly upregulates transcription factors involved in the promyelinating phase (e.g., Sox10 and Krox20) and downregulates proteins involved in the maintenance of the undifferentiated state (e.g., c-jun, Notch-1, and Jagged-1). Furthermore, arecaidine stimulation significantly increases the expression of myelin proteins, which is accompanied by evident changes in cell morphology, as indicated by electron microscopy analysis, and by substantial cellular re-distribution of actin and cell adhesion molecules. Moreover, ultrastructural and morphometric analyses on sciatic nerves of M2/M4 knockout mice show numerous degenerating axons and clear alterations in myelin organization compared with wild-type mice. Therefore, our data demonstrate that acetylcholine mediates axon-glia cross talk, favoring Schwann cell progression into a differentiated myelinating phenotype and contributing to compact myelin organization.
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Affiliation(s)
- Carolina Uggenti
- Dipartmento di Biologia e Biotecnologie "Charles Darwin,", "Sapienza" Università di Roma, Roma, Italy; Centro di ricerca in Neurobiologia "Daniel Bovet,", "Sapienza" Università di Roma, Roma, Italy
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SMN-dependent intrinsic defects in Schwann cells in mouse models of spinal muscular atrophy. Hum Mol Genet 2013; 23:2235-50. [DOI: 10.1093/hmg/ddt612] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
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Affiliation(s)
- Ben Emery
- Department of Anatomy and Neuroscience and Florey Institute of Neuroscience and Mental Health, University of Melbourne, Melbourne, Australia
- * E-mail:
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SWI/SNF enzymes promote SOX10- mediated activation of myelin gene expression. PLoS One 2013; 8:e69037. [PMID: 23874858 PMCID: PMC3712992 DOI: 10.1371/journal.pone.0069037] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Accepted: 06/04/2013] [Indexed: 12/21/2022] Open
Abstract
SOX10 is a Sry-related high mobility (HMG)-box transcriptional regulator that promotes differentiation of neural crest precursors into Schwann cells, oligodendrocytes, and melanocytes. Myelin, formed by Schwann cells in the peripheral nervous system, is essential for propagation of nerve impulses. SWI/SNF complexes are ATP dependent chromatin remodeling enzymes that are critical for cellular differentiation. It was recently demonstrated that the BRG1 subunit of SWI/SNF complexes activates SOX10 expression and also interacts with SOX10 to activate expression of OCT6 and KROX20, two transcriptional regulators of Schwann cell differentiation. To determine the requirement for SWI/SNF enzymes in the regulation of genes that encode components of myelin, which are downstream of these transcriptional regulators, we introduced SOX10 into fibroblasts that inducibly express dominant negative versions of the SWI/SNF ATPases, BRM or BRG1. Dominant negative BRM and BRG1 have mutations in the ATP binding site and inhibit gene activation events that require SWI/SNF function. Ectopic expression of SOX10 in cells derived from NIH 3T3 fibroblasts led to the activation of the endogenous Schwann cell specific gene, myelin protein zero (MPZ) and the gene that encodes myelin basic protein (MBP). Thus, SOX10 reprogrammed these cells into myelin gene expressing cells. Ectopic expression of KROX20 was not sufficient for activation of these myelin genes. However, KROX20 together with SOX10 synergistically activated MPZ and MBP expression. Dominant negative BRM and BRG1 abrogated SOX10 mediated activation of MPZ and MBP and synergistic activation of these genes by SOX10 and KROX20. SOX10 was required to recruit BRG1 to the MPZ locus. Similarly, in immortalized Schwann cells, BRG1 recruitment to SOX10 binding sites at the MPZ locus was dependent on SOX10 and expression of dominant negative BRG1 inhibited expression of MPZ and MBP in these cells. Thus, SWI/SNF enzymes cooperate with SOX10 to directly activate genes that encode components of peripheral myelin.
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Pingault V, Bodereau V, Baral V, Marcos S, Watanabe Y, Chaoui A, Fouveaut C, Leroy C, Vérier-Mine O, Francannet C, Dupin-Deguine D, Archambeaud F, Kurtz FJ, Young J, Bertherat J, Marlin S, Goossens M, Hardelin JP, Dodé C, Bondurand N. Loss-of-function mutations in SOX10 cause Kallmann syndrome with deafness. Am J Hum Genet 2013; 92:707-24. [PMID: 23643381 DOI: 10.1016/j.ajhg.2013.03.024] [Citation(s) in RCA: 140] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Revised: 02/25/2013] [Accepted: 03/29/2013] [Indexed: 12/11/2022] Open
Abstract
Transcription factor SOX10 plays a role in the maintenance of progenitor cell multipotency, lineage specification, and cell differentiation and is a major actor in the development of the neural crest. It has been implicated in Waardenburg syndrome (WS), a rare disorder characterized by the association between pigmentation abnormalities and deafness, but SOX10 mutations cause a variable phenotype that spreads over the initial limits of the syndrome definition. On the basis of recent findings of olfactory-bulb agenesis in WS individuals, we suspected SOX10 was also involved in Kallmann syndrome (KS). KS is defined by the association between anosmia and hypogonadotropic hypogonadism due to incomplete migration of neuroendocrine gonadotropin-releasing hormone (GnRH) cells along the olfactory, vomeronasal, and terminal nerves. Mutations in any of the nine genes identified to date account for only 30% of the KS cases. KS can be either isolated or associated with a variety of other symptoms, including deafness. This study reports SOX10 loss-of-function mutations in approximately one-third of KS individuals with deafness, indicating a substantial involvement in this clinical condition. Study of SOX10-null mutant mice revealed a developmental role of SOX10 in a subpopulation of glial cells called olfactory ensheathing cells. These mice indeed showed an almost complete absence of these cells along the olfactory nerve pathway, as well as defasciculation and misrouting of the nerve fibers, impaired migration of GnRH cells, and disorganization of the olfactory nerve layer of the olfactory bulbs.
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Affiliation(s)
- Veronique Pingault
- Equipe 11, Institut National de la Santé et de la Recherche Médicale Unité 955, 94000 Créteil, France.
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Kayam G, Kohl A, Magen Z, Peretz Y, Weisinger K, Bar A, Novikov O, Brodski C, Sela-Donenfeld D. A novel role for Pax6 in the segmental organization of the hindbrain. Development 2013; 140:2190-202. [PMID: 23578930 DOI: 10.1242/dev.089136] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Complex patterns and networks of genes coordinate rhombomeric identities, hindbrain segmentation and neuronal differentiation and are responsible for later brainstem functions. Pax6 is a highly conserved transcription factor crucial for neuronal development, yet little is known regarding its early roles during hindbrain segmentation. We show that Pax6 expression is highly dynamic in rhombomeres, suggesting an early function in the hindbrain. Utilization of multiple gain- and loss-of-function approaches in chick and mice revealed that loss of Pax6 disrupts the sharp expression borders of Krox20, Kreisler, Hoxa2, Hoxb1 and EphA and leads to their expansion into adjacent territories, whereas excess Pax6 reduces these expression domains. A mutual negative cross-talk between Pax6 and Krox20 allows these genes to be co-expressed in the hindbrain through regulation of the Krox20-repressor gene Nab1 by Pax6. Rhombomere boundaries are also distorted upon Pax6 manipulations, suggesting a mechanism by which Pax6 acts to set hindbrain segmentation. Finally, FGF signaling acts upstream of the Pax6-Krox20 network to regulate Pax6 segmental expression. This study unravels a novel role for Pax6 in the segmental organization of the early hindbrain and provides new evidence for its significance in regional organization along the central nervous system.
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Affiliation(s)
- Galya Kayam
- Koret School of Veterinary Medicine, The Hebrew University of Jerusalem, The Robert H. Smith Faculty of Agriculture, Food and Environment, 76100 Rehovot, Israel
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Li J, Parker B, Martyn C, Natarajan C, Guo J. The PMP22 gene and its related diseases. Mol Neurobiol 2012; 47:673-98. [PMID: 23224996 DOI: 10.1007/s12035-012-8370-x] [Citation(s) in RCA: 169] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2012] [Accepted: 10/22/2012] [Indexed: 10/27/2022]
Abstract
Peripheral myelin protein-22 (PMP22) is primarily expressed in the compact myelin of the peripheral nervous system. Levels of PMP22 have to be tightly regulated since alterations of PMP22 levels by mutations of the PMP22 gene are responsible for >50 % of all patients with inherited peripheral neuropathies, including Charcot-Marie-Tooth type-1A (CMT1A) with trisomy of PMP22, hereditary neuropathy with liability to pressure palsies (HNPP) with heterozygous deletion of PMP22, and CMT1E with point mutations of PMP22. While overexpression and point-mutations of the PMP22 gene may produce gain-of-function phenotypes, deletion of PMP22 results in a loss-of-function phenotype that reveals the normal physiological functions of the PMP22 protein. In this article, we will review the basic genetics, biochemistry and molecular structure of PMP22, followed by discussion of the current understanding of pathogenic mechanisms involving in the inherited neuropathies with mutations in PMP22 gene.
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Affiliation(s)
- Jun Li
- VA Tennessee Valley Healthcare System, 1310 24th Avenue South, Nashville, TN 37212, USA.
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Srinivasan R, Sun G, Keles S, Jones EA, Jang SW, Krueger C, Moran JJ, Svaren J. Genome-wide analysis of EGR2/SOX10 binding in myelinating peripheral nerve. Nucleic Acids Res 2012; 40:6449-60. [PMID: 22492709 PMCID: PMC3413122 DOI: 10.1093/nar/gks313] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Revised: 03/25/2012] [Accepted: 03/26/2012] [Indexed: 11/17/2022] Open
Abstract
Myelin is essential for the rapidity of saltatory nerve conduction, and also provides trophic support for axons to prevent axonal degeneration. Two critical determinants of myelination are SOX10 and EGR2/KROX20. SOX10 is required for specification of Schwann cells from neural crest, and is required at every stage of Schwann cell development. Egr2/Krox20 expression is activated by axonal signals in myelinating Schwann cells, and is required for cell cycle arrest and myelin formation. To elucidate the integrated function of these two transcription factors during peripheral nerve myelination, we performed in vivo ChIP-Seq analysis of myelinating peripheral nerve. Integration of these binding data with loss-of-function array data identified a range of genes regulated by these factors. In addition, although SOX10 itself regulates Egr2/Krox20 expression, leading to coordinate activation of several major myelin genes by the two factors, there is a large subset of genes that are activated independent of EGR2. Finally, the results identify a set of SOX10-dependent genes that are expressed in early Schwann cell development, but become subsequently repressed by EGR2/KROX20.
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Affiliation(s)
- Rajini Srinivasan
- Waisman Center, Department of Statistics, Department of Biostatistics and Medical Informatics, Program in Cellular and Molecular Biology and, Department of Comparative Biosciences, University of Wisconsin, Madison, WI, USA
| | - Guannan Sun
- Waisman Center, Department of Statistics, Department of Biostatistics and Medical Informatics, Program in Cellular and Molecular Biology and, Department of Comparative Biosciences, University of Wisconsin, Madison, WI, USA
| | - Sunduz Keles
- Waisman Center, Department of Statistics, Department of Biostatistics and Medical Informatics, Program in Cellular and Molecular Biology and, Department of Comparative Biosciences, University of Wisconsin, Madison, WI, USA
| | - Erin A. Jones
- Waisman Center, Department of Statistics, Department of Biostatistics and Medical Informatics, Program in Cellular and Molecular Biology and, Department of Comparative Biosciences, University of Wisconsin, Madison, WI, USA
| | - Sung-Wook Jang
- Waisman Center, Department of Statistics, Department of Biostatistics and Medical Informatics, Program in Cellular and Molecular Biology and, Department of Comparative Biosciences, University of Wisconsin, Madison, WI, USA
| | - Courtney Krueger
- Waisman Center, Department of Statistics, Department of Biostatistics and Medical Informatics, Program in Cellular and Molecular Biology and, Department of Comparative Biosciences, University of Wisconsin, Madison, WI, USA
| | - John J. Moran
- Waisman Center, Department of Statistics, Department of Biostatistics and Medical Informatics, Program in Cellular and Molecular Biology and, Department of Comparative Biosciences, University of Wisconsin, Madison, WI, USA
| | - John Svaren
- Waisman Center, Department of Statistics, Department of Biostatistics and Medical Informatics, Program in Cellular and Molecular Biology and, Department of Comparative Biosciences, University of Wisconsin, Madison, WI, USA
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45
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Hossain S, de la Cruz-Morcillo MA, Sanchez-Prieto R, Almazan G. Mitogen-activated protein kinase p38 regulates krox-20 to direct schwann cell differentiation and peripheral myelination. Glia 2012; 60:1130-44. [DOI: 10.1002/glia.22340] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Accepted: 03/16/2012] [Indexed: 12/24/2022]
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46
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Jones EA, Brewer MH, Srinivasan R, Krueger C, Sun G, Charney KN, Keles S, Antonellis A, Svaren J. Distal enhancers upstream of the Charcot-Marie-Tooth type 1A disease gene PMP22. Hum Mol Genet 2012; 21:1581-91. [PMID: 22180461 PMCID: PMC3298281 DOI: 10.1093/hmg/ddr595] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2011] [Accepted: 12/12/2011] [Indexed: 11/14/2022] Open
Abstract
Myelin insulates axons in the peripheral nervous system to allow rapid propagation of action potentials, and proper myelination requires the precise regulation of genes encoding myelin proteins, including PMP22. The correct gene dosage of PMP22 is critical; a duplication of PMP22 is the most common cause of the peripheral neuropathy Charcot-Marie-Tooth Disease (CMT) (classified as type 1A), while a deletion of PMP22 leads to another peripheral neuropathy, hereditary neuropathy with liability to pressure palsies. Recently, duplications upstream of PMP22, but not containing the gene itself, were reported in patients with CMT1A like symptoms, suggesting that this region contains regulators of PMP22. Using chromatin immunoprecipitation analysis of two transcription factors known to upregulate PMP22-EGR2 and SOX10-we found several enhancers in this upstream region that contain open chromatin and direct reporter gene expression in tissue culture and in vivo in zebrafish. These studies provide a novel means to identify critical regulatory elements in genes that are required for myelination, and elucidate the functional significance of non-coding genomic rearrangements.
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Affiliation(s)
- Erin A. Jones
- Program in Cellular and Molecular Biology
- Waisman Center
| | | | | | | | - Guannan Sun
- Department of Statistics
- Department of Biostatistics and Medical Informatics and
| | | | - Sunduz Keles
- Department of Statistics
- Department of Biostatistics and Medical Informatics and
| | - Anthony Antonellis
- Department of Human Genetics
- Department of Neurology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - John Svaren
- Waisman Center
- Department of Comparative Biosciences, Waisman Center, University of Wisconsin, Madison, WI 53705, USA
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Hodonsky CJ, Kleinbrink EL, Charney KN, Prasad M, Bessling SL, Jones EA, Srinivasan R, Svaren J, McCallion AS, Antonellis A. SOX10 regulates expression of the SH3-domain kinase binding protein 1 (Sh3kbp1) locus in Schwann cells via an alternative promoter. Mol Cell Neurosci 2011; 49:85-96. [PMID: 22037207 DOI: 10.1016/j.mcn.2011.10.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Revised: 10/07/2011] [Accepted: 10/11/2011] [Indexed: 12/31/2022] Open
Abstract
The transcription factor SOX10 has essential roles in neural crest-derived cell populations, including myelinating Schwann cells-specialized glial cells responsible for ensheathing axons in the peripheral nervous system. Importantly, SOX10 directly regulates the expression of genes essential for proper myelin function. To date, only a handful of SOX10 target loci have been characterized in Schwann cells. Addressing this lack of knowledge will provide a better understanding of Schwann cell biology and candidate loci for relevant diseases such as demyelinating peripheral neuropathies. We have identified a highly-conserved SOX10 binding site within an alternative promoter at the SH3-domain kinase binding protein 1 (Sh3kbp1) locus. The genomic segment identified at Sh3kbp1 binds to SOX10 and displays strong promoter activity in Schwann cells in vitro and in vivo. Mutation of the SOX10 binding site ablates promoter activity, and ectopic expression of SOX10 in SOX10-negative cells promotes the expression of endogenous Sh3kbp1. Combined, these data reveal Sh3kbp1 as a novel target of SOX10 and raise important questions regarding the function of SH3KBP1 isoforms in Schwann cells.
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Affiliation(s)
- Chani J Hodonsky
- Department of Human Genetics, University of Michigan Medical School, Ann Arbor, MI, USA
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48
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Jacob C, Christen CN, Pereira JA, Somandin C, Baggiolini A, Lötscher P, Ozçelik M, Tricaud N, Meijer D, Yamaguchi T, Matthias P, Suter U. HDAC1 and HDAC2 control the transcriptional program of myelination and the survival of Schwann cells. Nat Neurosci 2011; 14:429-36. [PMID: 21423190 DOI: 10.1038/nn.2762] [Citation(s) in RCA: 126] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2010] [Accepted: 01/24/2011] [Indexed: 12/15/2022]
Abstract
Histone deacetylases (HDACs) are major epigenetic regulators. We show that HDAC1 and HDAC2 functions are critical for myelination of the peripheral nervous system. Using mouse genetics, we have ablated Hdac1 and Hdac2 specifically in Schwann cells, resulting in massive Schwann cell loss and virtual absence of myelin in mutant sciatic nerves. Expression of Sox10 and Krox20, the main transcriptional regulators of Schwann cell myelination, was greatly reduced. We demonstrate that in Schwann cells, HDAC1 and HDAC2 exert specific primary functions: HDAC2 activates the transcriptional program of myelination in synergy with Sox10, whereas HDAC1 controls Schwann cell survival by regulating the levels of active β-catenin.
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Affiliation(s)
- Claire Jacob
- Institute of Cell Biology, Department of Biology, ETH Zurich, Zurich, Switzerland.
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49
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Jones EA, Lopez-Anido C, Srinivasan R, Krueger C, Chang LW, Nagarajan R, Svaren J. Regulation of the PMP22 gene through an intronic enhancer. J Neurosci 2011; 31:4242-50. [PMID: 21411665 PMCID: PMC3100536 DOI: 10.1523/jneurosci.5893-10.2011] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2010] [Revised: 01/17/2011] [Accepted: 01/21/2011] [Indexed: 11/21/2022] Open
Abstract
Successful myelination of the peripheral nervous system depends upon induction of major protein components of myelin, such as peripheral myelin protein 22 (PMP22). Myelin stability is also sensitive to levels of PMP22, as a 1.4 Mb duplication on human chromosome 17, resulting in three copies of PMP22, is the most common cause of the peripheral neuropathy Charcot-Marie-Tooth disease. The transcription factor Egr2/Krox20 is required for induction of high level expression of Pmp22 in Schwann cells but its activation elements have not yet been determined. Using chromatin immunoprecipitation analysis of the rat Pmp22 locus, we found a major peak of Egr2 binding within the large intron of the Pmp22 gene. Analysis of a 250 bp region within the largest intron showed that it is strongly activated by Egr2 expression in reporter assays. Moreover, this region contains conserved binding sites not only for Egr2 but also for Sox10, which is also required for Schwann cell development. Our analysis shows that Sox10 is required for optimal activity of the intronic site as well as PMP22 expression. Finally, mouse transgenic analysis revealed tissue-specific expression of this intronic sequence in peripheral nerve. Overall, these data show that Egr2 and Sox10 activity are directly involved in mediating the developmental induction of Pmp22 expression.
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Affiliation(s)
| | | | - Rajini Srinivasan
- Waisman Center, University of Wisconsin, Madison, Wisconsin 53705, and
| | - Courtney Krueger
- Waisman Center, University of Wisconsin, Madison, Wisconsin 53705, and
| | - Li-Wei Chang
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, Missouri 63110
| | - Rakesh Nagarajan
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, Missouri 63110
| | - John Svaren
- Department of Comparative Biosciences, and
- Waisman Center, University of Wisconsin, Madison, Wisconsin 53705, and
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50
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Arthur-Farraj P, Wanek K, Hantke J, Davis CM, Jayakar A, Parkinson DB, Mirsky R, Jessen KR. Mouse schwann cells need both NRG1 and cyclic AMP to myelinate. Glia 2011; 59:720-33. [PMID: 21322058 DOI: 10.1002/glia.21144] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2010] [Accepted: 12/20/2010] [Indexed: 12/13/2022]
Abstract
Genetically modified mice have been a major source of information about the molecular control of Schwann-cell myelin formation, and the role of β-neuregulin 1 (NRG1) in this process in vivo. In vitro, on the other hand, Schwann cells from rats have been used in most analyses of the signaling pathways involved in myelination. To correlate more effectively in vivo and in vitro data, we used purified cultures of mouse Schwann cells in addition to rat Schwann cells to examine two important myelin-related signals, cyclic adenosine monophosphate (cAMP), and NRG1 and to determine whether they interact to control myelin differentiation. We find that in mouse Schwann cells, neither cAMP nor NRG1, when used separately, induced markers of myelin differentiation. When combined, however, they induced strong protein expression of the myelin markers, Krox-20 and P(0) . Importantly, the level of cAMP signaling was crucial in switching NRG1 from a proliferative signal to a myelin differentiation signal. Also in cultured rat Schwann cells, NRG1 promoted cAMP-induced Krox-20 and P(0) expression. Finally, we found that cAMP/NRG1-induced Schwann-cell differentiation required the activity of the cAMP response element binding family of transcription factors in both mouse and rat cells. These observations reconcile observations in vivo and on neuron-Schwann-cell cultures with studies on purified Schwann cells. They demonstrate unambiguously the promyelin effects of NRG1 in purified cells, and they show that the cAMP pathway determines whether NRG1 drives proliferation or induces myelin differentiation.
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Affiliation(s)
- Peter Arthur-Farraj
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, United Kingdom
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