1
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Teng XY, Hu P, Zhang CM, Zhang QX, Yang G, Zang YY, Liu ZX, Chen G, Shi YS. OPALIN is an LGI1 receptor promoting oligodendrocyte differentiation. Proc Natl Acad Sci U S A 2024; 121:e2403652121. [PMID: 39083419 PMCID: PMC11317624 DOI: 10.1073/pnas.2403652121] [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: 02/23/2024] [Accepted: 07/02/2024] [Indexed: 08/02/2024] Open
Abstract
Leucine-rich glioma-inactivated protein 1 (LGI1), a secretory protein in the brain, plays a critical role in myelination; dysfunction of this protein leads to hypomyelination and white matter abnormalities (WMAs). Here, we hypothesized that LGI1 may regulate myelination through binding to an unidentified receptor on the membrane of oligodendrocytes (OLs). To search for this hypothetic receptor, we analyzed LGI1 binding proteins through LGI1-3 × FLAG affinity chromatography with mouse brain lysates followed by mass spectrometry. An OL-specific membrane protein, the oligodendrocytic myelin paranodal and inner loop protein (OPALIN), was identified. Conditional knockout (cKO) of OPALIN in the OL lineage caused hypomyelination and WMAs, phenocopying LGI1 deficiency in mice. Biochemical analysis revealed the downregulation of Sox10 and Olig2, transcription factors critical for OL differentiation, further confirming the impaired OL maturation in Opalin cKO mice. Moreover, virus-mediated re-expression of OPALIN successfully restored myelination in Opalin cKO mice. In contrast, re-expression of LGI1-unbound OPALIN_K23A/D26A failed to reverse the hypomyelination phenotype. In conclusion, our study demonstrated that OPALIN on the OL membrane serves as an LGI1 receptor, highlighting the importance of the LGI1/OPALIN complex in orchestrating OL differentiation and myelination.
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Affiliation(s)
- Xiao-Yu Teng
- Guangdong Institute of Intelligence Science and Technology, 519031Hengqin, Zhuhai, China
- Ministry of Education Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, 210032Nanjing, China
| | - Ping Hu
- Department of Prenatal Diagnosis, State Key Laboratory of Reproductive Medicine, Women’s Hospital of Nanjing Medical University, Nanjing Women and Children’s Healthcare Hospital, 210004Nanjing, China
| | - Cai-Ming Zhang
- Department of Thoracic Surgery, Integrated Hospital of Traditional Chinese Medicine, Southern Medical University, 510315Guangzhou, China
| | - Qin-Xin Zhang
- Department of Prenatal Diagnosis, State Key Laboratory of Reproductive Medicine, Women’s Hospital of Nanjing Medical University, Nanjing Women and Children’s Healthcare Hospital, 210004Nanjing, China
| | - Guolin Yang
- Ministry of Education Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, 210032Nanjing, China
| | - Yan-Yu Zang
- Ministry of Education Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, 210032Nanjing, China
| | - Zhi-Xiong Liu
- Guangdong Institute of Intelligence Science and Technology, 519031Hengqin, Zhuhai, China
| | - Guiquan Chen
- Ministry of Education Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, 210032Nanjing, China
| | - Yun Stone Shi
- Guangdong Institute of Intelligence Science and Technology, 519031Hengqin, Zhuhai, China
- Ministry of Education Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, 210032Nanjing, China
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2
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Kozar-Gillan N, Velichkova A, Kanatouris G, Eshed-Eisenbach Y, Steel G, Jaegle M, Aunin E, Peles E, Torsney C, Meijer DN. LGI3/2-ADAM23 interactions cluster Kv1 channels in myelinated axons to regulate refractory period. J Cell Biol 2023; 222:e202211031. [PMID: 36828548 PMCID: PMC9997507 DOI: 10.1083/jcb.202211031] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 12/18/2022] [Accepted: 01/17/2023] [Indexed: 02/26/2023] Open
Abstract
Along myelinated axons, Shaker-type potassium channels (Kv1) accumulate at high density in the juxtaparanodal region, directly adjacent to the paranodal axon-glia junctions that flank the nodes of Ranvier. However, the mechanisms that control the clustering of Kv1 channels, as well as their function at this site, are still poorly understood. Here we demonstrate that axonal ADAM23 is essential for both the accumulation and stability of juxtaparanodal Kv1 complexes. The function of ADAM23 is critically dependent on its interaction with its extracellular ligands LGI2 and LGI3. Furthermore, we demonstrate that juxtaparanodal Kv1 complexes affect the refractory period, thus enabling high-frequency burst firing of action potentials. Our findings not only reveal a previously unknown molecular pathway that regulates Kv1 channel clustering, but they also demonstrate that the juxtaparanodal Kv1 channels that are concealed below the myelin sheath, play a significant role in modifying axonal physiology.
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Affiliation(s)
- Nina Kozar-Gillan
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh. UK
| | | | - George Kanatouris
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh. UK
| | - Yael Eshed-Eisenbach
- Department of Molecular Cell Biology and Molecular Neurobiology, Weizmann Institute of Science, Rehovot, Israel
| | - Gavin Steel
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh. UK
| | | | - Eerik Aunin
- Biomedical Sciences, ErasmusMC, Rotterdam, Netherlands
| | - Elior Peles
- Department of Molecular Cell Biology and Molecular Neurobiology, Weizmann Institute of Science, Rehovot, Israel
| | - Carole Torsney
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh. UK
- Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh. UK
| | - Dies N. Meijer
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh. UK
- Muir Maxwell Epilepsy Centre, University of Edinburgh, Edinburgh, UK
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3
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Rodriguez CM, Bechek SC, Jones GL, Nakayama L, Akiyama T, Kim G, Solow-Cordero DE, Strittmatter SM, Gitler AD. Targeting RTN4/NoGo-Receptor reduces levels of ALS protein ataxin-2. Cell Rep 2022; 41:111505. [PMID: 36288715 PMCID: PMC9664481 DOI: 10.1016/j.celrep.2022.111505] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 05/30/2022] [Accepted: 09/22/2022] [Indexed: 01/27/2023] Open
Abstract
Gene-based therapeutic strategies to lower ataxin-2 levels are emerging for the neurodegenerative diseases amyotrophic lateral sclerosis (ALS) and spinocerebellar ataxia type 2 (SCA2). Additional strategies to lower levels of ataxin-2 could be beneficial. Here, we perform a genome-wide arrayed small interfering RNA (siRNA) screen in human cells and identify RTN4R, the gene encoding the RTN4/NoGo-Receptor, as a potent modifier of ataxin-2 levels. RTN4R knockdown, or treatment with a peptide inhibitor, is sufficient to lower ataxin-2 protein levels in mouse and human neurons in vitro, and Rtn4r knockout mice have reduced ataxin-2 levels in vivo. We provide evidence that ataxin-2 shares a role with the RTN4/NoGo-Receptor in limiting axonal regeneration. Reduction of either protein increases axonal regrowth following axotomy. These data define the RTN4/NoGo-Receptor as a novel therapeutic target for ALS and SCA2 and implicate the targeting of ataxin-2 as a potential treatment following nerve injury.
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Affiliation(s)
- Caitlin M Rodriguez
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Sophia C Bechek
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Graham L Jones
- Department of Neurosurgery, Stanford University School of Medicine, Stanford, CA, USA
| | - Lisa Nakayama
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Tetsuya Akiyama
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Garam Kim
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA; Stanford Neurosciences Interdepartmental Program, Stanford University School of Medicine, Stanford, CA, USA
| | - David E Solow-Cordero
- High-Throughput Bioscience Center, Department of Chemical and Systems Biology, Stanford University, Stanford, CA, USA
| | - Stephen M Strittmatter
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven, CT, USA
| | - Aaron D Gitler
- Department of Genetics, Stanford University School of Medicine, Stanford, CA 94305, USA.
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4
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Liang L, Tian Y, Feng L, Wang C, Feng G, Stacey GN, Shyh-Chang N, Wu J, Hu B, Li W, Hao J, Wang L, Wang Y. Single-cell transcriptomics reveals the cell fate transitions of human dopaminergic progenitors derived from hESCs. Stem Cell Res Ther 2022; 13:412. [PMID: 35964138 PMCID: PMC9375405 DOI: 10.1186/s13287-022-03104-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Accepted: 07/31/2022] [Indexed: 11/10/2022] Open
Abstract
Background Midbrain dopaminergic (DA) progenitors derived from human pluripotent stem cells are considered to be a promising treatment for Parkinson’s disease (PD). However, the differentiation process produces undesired cell types, which influence the in vivo evaluation of DA cells. In this paper, we analyze the cell fate choice during differentiation and provide valuable information on cell preparation. Methods Human embryonic stem cells were differentiated into DA progenitors. We applied single-cell RNA sequencing (scRNA-seq) of the differentiation cells at different time points and investigated the gene expression profiles. Based on the differentially expressed genes between DA and non-DA cells, we investigated the impact of LGI1 (DA enriched) overexpression on DA differentiation and the enrichment effect of CD99 (non-DA enriched) sorting. Results Transcriptome analyses revealed the DA differentiation trajectory as well as non-DA populations and three key lineage branch points. Using genetic gain- and loss-of-function approaches, we found that overexpression of LGI1, which is specific to EN1+ early DA progenitors, can promote the generation of TH+ neurons. We also found that choroid plexus epithelial cells and DA progenitors are major components of the final product (day 25), and CD99 was a specific surface marker of choroid plexus epithelial cells. Sorting of CD99− cells eliminated major contaminant cells and improved the purity of DA progenitors. Conclusions Our study provides the single-cell transcriptional landscape of in vitro DA differentiation, which can guide future improvements in DA preparation and quality control for PD cell therapy. Supplementary Information The online version contains supplementary material available at 10.1186/s13287-022-03104-7.
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Affiliation(s)
- Lingmin Liang
- Savaid Medical School, University of Chinese Academy of Sciences, Beijing, 100049, China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, 100101, China.,Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China.,National Stem Cell Resource Center, Chinese Academy of Sciences, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 100864, China
| | - Yao Tian
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, 100101, China.,Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China.,National Stem Cell Resource Center, Chinese Academy of Sciences, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 100864, China
| | - Lin Feng
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, 100101, China.,Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China.,National Stem Cell Resource Center, Chinese Academy of Sciences, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 100864, China
| | - Chaoqun Wang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.,Savaid Medical School, University of Chinese Academy of Sciences, Beijing, 100049, China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, 100101, China.,Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China.,University of Chinese Academy of Sciences, Beijing, 100864, China
| | - Guihai Feng
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, 100101, China.,Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China
| | - Glyn Nigel Stacey
- National Stem Cell Resource Center, Chinese Academy of Sciences, Beijing, 100101, China.,International Stem Cell Banking Initiative, Hertfordshire, UK
| | - Ng Shyh-Chang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, 100101, China.,Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China.,University of Chinese Academy of Sciences, Beijing, 100864, China
| | - Jun Wu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, 100101, China.,Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China.,National Stem Cell Resource Center, Chinese Academy of Sciences, Beijing, 100101, China
| | - Baoyang Hu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.,Savaid Medical School, University of Chinese Academy of Sciences, Beijing, 100049, China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, 100101, China.,Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China.,National Stem Cell Resource Center, Chinese Academy of Sciences, Beijing, 100101, China.,University of Chinese Academy of Sciences, Beijing, 100864, China
| | - Wei Li
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, 100101, China.,Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China.,University of Chinese Academy of Sciences, Beijing, 100864, China
| | - Jie Hao
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China.,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, 100101, China.,Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China.,National Stem Cell Resource Center, Chinese Academy of Sciences, Beijing, 100101, China
| | - Liu Wang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China. .,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, 100101, China. .,Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China. .,National Stem Cell Resource Center, Chinese Academy of Sciences, Beijing, 100101, China. .,University of Chinese Academy of Sciences, Beijing, 100864, China.
| | - Yukai Wang
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China. .,Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, Beijing, 100101, China. .,Beijing Institute for Stem Cell and Regenerative Medicine, Beijing, China. .,National Stem Cell Resource Center, Chinese Academy of Sciences, Beijing, 100101, China.
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5
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Teng X, Hu P, Chen Y, Zang Y, Ye X, Ou J, Chen G, Shi YS. A novel
Lgi1
mutation causes white matter abnormalities and impairs motor coordination in mice. FASEB J 2022; 36:e22212. [DOI: 10.1096/fj.202101652r] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 01/18/2022] [Accepted: 02/03/2022] [Indexed: 12/22/2022]
Affiliation(s)
- Xiao‐Yu Teng
- Minister of Education Key Laboratory of Model Animal for Disease Study Model Animal Research Center, Medical School Nanjing University Nanjing China
| | - Ping Hu
- Department of Prenatal Diagnosis State Key Laboratory of Reproductive Medicine Women's Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital Nanjing China
| | - Yangyang Chen
- Minister of Education Key Laboratory of Model Animal for Disease Study Model Animal Research Center, Medical School Nanjing University Nanjing China
| | - Yanyu Zang
- Minister of Education Key Laboratory of Model Animal for Disease Study Model Animal Research Center, Medical School Nanjing University Nanjing China
| | - Xiaolian Ye
- Minister of Education Key Laboratory of Model Animal for Disease Study Model Animal Research Center, Medical School Nanjing University Nanjing China
| | - Jingmin Ou
- Department of General Surgery Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine Shanghai China
| | - Guiquan Chen
- Minister of Education Key Laboratory of Model Animal for Disease Study Model Animal Research Center, Medical School Nanjing University Nanjing China
| | - Yun Stone Shi
- Minister of Education Key Laboratory of Model Animal for Disease Study Model Animal Research Center, Medical School Nanjing University Nanjing China
- State Key Laboratory of Pharmaceutical Biotechnology Department of Neurology Affiliated Drum Tower Hospital of Nanjing University Medical School Nanjing University Nanjing China
- Institute for Brain Sciences Nanjing University Nanjing China
- Chemistry and Biomedicine Innovation Center Nanjing University Nanjing China
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6
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Baudin P, Cousyn L, Navarro V. The LGI1 protein: molecular structure, physiological functions and disruption-related seizures. Cell Mol Life Sci 2021; 79:16. [PMID: 34967933 PMCID: PMC11072701 DOI: 10.1007/s00018-021-04088-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 12/07/2021] [Accepted: 12/09/2021] [Indexed: 01/16/2023]
Abstract
Leucine-rich, glioma inactivated 1 (LGI1) is a secreted glycoprotein, mainly expressed in the brain, and involved in central nervous system development and physiology. Mutations of LGI1 have been linked to autosomal dominant lateral temporal lobe epilepsy (ADLTE). Recently auto-antibodies against LGI1 have been described as the basis for an autoimmune encephalitis, associated with specific motor and limbic epileptic seizures. It is the second most common cause of autoimmune encephalitis. This review presents details on the molecular structure, expression and physiological functions of LGI1, and examines how their disruption underlies human pathologies. Knock-down of LGI1 in rodents reveals that this protein is necessary for normal brain development. In mature brains, LGI1 is associated with Kv1 channels and AMPA receptors, via domain-specific interaction with membrane anchoring proteins and contributes to regulation of the expression and function of these channels. Loss of function, due to mutations or autoantibodies, of this key protein in the control of neuronal activity is a common feature in the genesis of epileptic seizures in ADLTE and anti-LGI1 autoimmune encephalitis.
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Affiliation(s)
- Paul Baudin
- Sorbonne Université, Paris Brain Institute - Institut du Cerveau, ICM, INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, Paris, France
| | - Louis Cousyn
- Sorbonne Université, Paris Brain Institute - Institut du Cerveau, ICM, INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, Paris, France
- AP-HP, Epilepsy Unit, Pitié-Salpêtrière Hospital, DMU Neurosciences, Paris, France
| | - Vincent Navarro
- Sorbonne Université, Paris Brain Institute - Institut du Cerveau, ICM, INSERM, CNRS, AP-HP, Pitié-Salpêtrière Hospital, Paris, France.
- AP-HP, Epilepsy Unit, Pitié-Salpêtrière Hospital, DMU Neurosciences, Paris, France.
- AP-HP, Center of Reference for Rare Epilepsies, Pitié-Salpêtrière Hospital, 47-83 Boulevard de l'Hôpital, 75013, Paris, France.
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7
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Hu P, Wu D, Zang YY, Wang Y, Zhou YP, Qiao F, Teng XY, Chen J, Li QQ, Sun JH, Liu T, Feng HY, Zhou QG, Shi YS, Xu Z. A novel LGI1 mutation causing autosomal dominant lateral temporal lobe epilepsy confirmed by a precise knock-in mouse model. CNS Neurosci Ther 2021; 28:237-246. [PMID: 34767694 PMCID: PMC8739050 DOI: 10.1111/cns.13761] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 10/20/2021] [Accepted: 10/25/2021] [Indexed: 12/30/2022] Open
Abstract
AIMS This study aimed to explore the pathomechanism of a mutation on the leucine-rich glioma inactivated 1 gene (LGI1) identified in a family having autosomal dominant lateral temporal lobe epilepsy (ADLTE), using a precise knock-in mouse model. METHODS AND RESULTS A novel LGI1 mutation, c.152A>G; p. Asp51Gly, was identified by whole exome sequencing in a Chinese family with ADLTE. The pathomechanism of the mutation was explored by generating Lgi1D51G knock-in mice that precisely phenocopied the epileptic symptoms of human patients. The Lgi1D51G / D51G mice showed spontaneous recurrent generalized seizures and premature death. The Lgi1D51G /+ mice had partial epilepsy, with half of them displaying epileptiform discharges on electroencephalography. They also showed enhanced sensitivity to the convulsant agent pentylenetetrazole. Mechanistically, the secretion of Lgi1 was impaired in the brain of the D51G knock-in mice and the protein level was drastically reduced. Moreover, the antiepileptic drugs, carbamazepine, oxcarbazepine, and sodium valproate, could prolong the survival time of Lgi1D51G / D51G mice, and oxcarbazepine appeared to be the most effective. CONCLUSIONS We identified a novel epilepsy-causing mutation of LGI1 in humans. The Lgi1D51G /+ mouse model, precisely phenocopying epileptic symptoms of human patients, could be a useful tool in future studies on the pathogenesis and potential therapies for epilepsy.
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Affiliation(s)
- Ping Hu
- Department of Prenatal Diagnosis, Women's Hospital of Nanjing Medical University, Nanjing Maternity and Child Health care Hospital, Nanjing, China
| | - Dan Wu
- Minister of Education Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Department of Neurology, Drum Tower Hospital, Medical School, Nanjing University, Nanjing, China.,State Key Laboratory of Pharmaceutical Biotechnology, National Resource for Mutant Mice, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing, China
| | - Yan-Yu Zang
- Minister of Education Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Department of Neurology, Drum Tower Hospital, Medical School, Nanjing University, Nanjing, China.,State Key Laboratory of Pharmaceutical Biotechnology, National Resource for Mutant Mice, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing, China
| | - Yan Wang
- Department of Prenatal Diagnosis, Women's Hospital of Nanjing Medical University, Nanjing Maternity and Child Health care Hospital, Nanjing, China
| | - Ya-Ping Zhou
- School of Pharmacy, Nanjing Medical University, Nanjing, China
| | - Fengchang Qiao
- Department of Prenatal Diagnosis, Women's Hospital of Nanjing Medical University, Nanjing Maternity and Child Health care Hospital, Nanjing, China
| | - Xiao-Yu Teng
- Minister of Education Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Department of Neurology, Drum Tower Hospital, Medical School, Nanjing University, Nanjing, China.,State Key Laboratory of Pharmaceutical Biotechnology, National Resource for Mutant Mice, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing, China
| | - Jiang Chen
- Minister of Education Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Department of Neurology, Drum Tower Hospital, Medical School, Nanjing University, Nanjing, China.,State Key Laboratory of Pharmaceutical Biotechnology, National Resource for Mutant Mice, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing, China
| | - Qing-Qing Li
- Minister of Education Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Department of Neurology, Drum Tower Hospital, Medical School, Nanjing University, Nanjing, China.,State Key Laboratory of Pharmaceutical Biotechnology, National Resource for Mutant Mice, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing, China
| | - Jia-Hui Sun
- Minister of Education Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Department of Neurology, Drum Tower Hospital, Medical School, Nanjing University, Nanjing, China.,State Key Laboratory of Pharmaceutical Biotechnology, National Resource for Mutant Mice, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing, China
| | - TingTing Liu
- Minister of Education Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Department of Neurology, Drum Tower Hospital, Medical School, Nanjing University, Nanjing, China.,State Key Laboratory of Pharmaceutical Biotechnology, National Resource for Mutant Mice, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing, China
| | - Hao-Yang Feng
- Department of Prenatal Diagnosis, Women's Hospital of Nanjing Medical University, Nanjing Maternity and Child Health care Hospital, Nanjing, China
| | - Qi-Gang Zhou
- School of Pharmacy, Nanjing Medical University, Nanjing, China
| | - Yun Stone Shi
- Minister of Education Key Laboratory of Model Animal for Disease Study, Model Animal Research Center, Department of Neurology, Drum Tower Hospital, Medical School, Nanjing University, Nanjing, China.,State Key Laboratory of Pharmaceutical Biotechnology, National Resource for Mutant Mice, Jiangsu Key Laboratory of Molecular Medicine, Medical School, Nanjing University, Nanjing, China.,Chemistry and Biomedicine Innovation Center, Nanjing University, Nanjing, China.,Institute for Brain Sciences, Nanjing University, Nanjing, China
| | - Zhengfeng Xu
- Department of Prenatal Diagnosis, Women's Hospital of Nanjing Medical University, Nanjing Maternity and Child Health care Hospital, Nanjing, China
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8
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Perveen N, Ashraf W, Alqahtani F, Fawad Rasool M, Samad N, Imran I. Temporal Lobe Epilepsy: What do we understand about protein alterations? Chem Biol Drug Des 2021; 98:377-394. [PMID: 34132061 DOI: 10.1111/cbdd.13858] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 03/22/2021] [Accepted: 04/18/2021] [Indexed: 01/19/2023]
Abstract
During neuronal diseases, neuronal proteins get disturbed due to changes in the connections of neurons. As a result, neuronal proteins get disturbed and cause epilepsy. At the genetic level, many mutations may take place in proteins like axon guidance proteins, leucine-rich glioma inactivated 1 protein, microtubular protein, pore-forming, chromatin remodeling, and chemokine proteins which may lead toward temporal lobe epilepsy. These proteins can be targeted in the future for the treatment purpose of epilepsy. Novel avenues can be developed for therapeutic interventions by these new insights.
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Affiliation(s)
- Nadia Perveen
- Department of Pharmacology, Faculty of Pharmacy, Bahauddin Zakariya University, Multan, Pakistan
| | - Waseem Ashraf
- Department of Pharmacology, Faculty of Pharmacy, Bahauddin Zakariya University, Multan, Pakistan
| | - Faleh Alqahtani
- Department of Pharmacology and Toxicology, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
| | - Muhammad Fawad Rasool
- Department of Pharmacy Practice, Faculty of Pharmacy, Bahauddin Zakariya University, Multan, Pakistan
| | - Noreen Samad
- Department of Biochemistry, Faculty of Science, Bahauddin Zakariya University, Multan, Pakistan
| | - Imran Imran
- Department of Pharmacology, Faculty of Pharmacy, Bahauddin Zakariya University, Multan, Pakistan
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9
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LOTUS, an endogenous Nogo receptor antagonist, is involved in synapse and memory formation. Sci Rep 2021; 11:5085. [PMID: 33658590 PMCID: PMC7930056 DOI: 10.1038/s41598-021-84106-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Accepted: 02/12/2021] [Indexed: 11/29/2022] Open
Abstract
The Nogo signal is involved in impairment of memory formation. We previously reported the lateral olfactory tract usher substance (LOTUS) as an endogenous antagonist of the Nogo receptor 1 that mediates the inhibition of axon growth and synapse formation. Moreover, we found that LOTUS plays an essential role in neural circuit formation and nerve regeneration. However, the effects of LOTUS on synapse formation and memory function have not been elucidated. Here, we clearly showed the involvement of LOTUS in synapse formation and memory function. The cultured hippocampal neurons derived from lotus gene knockout (LOTUS-KO) mice exhibited a decrease in synaptic density compared with those from wild-type mice. We also found decrease of dendritic spine formation in the adult hippocampus of LOTUS-KO mice. Finally, we demonstrated that LOTUS deficiency impairs memory formation in the social recognition test and the Morris water maze test, indicating that LOTUS is involved in functions of social and spatial learning and memory. These findings suggest that LOTUS affects synapse formation and memory function.
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Yamagata A, Fukai S. Insights into the mechanisms of epilepsy from structural biology of LGI1-ADAM22. Cell Mol Life Sci 2020; 77:267-274. [PMID: 31432233 PMCID: PMC11104983 DOI: 10.1007/s00018-019-03269-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 08/05/2019] [Accepted: 08/09/2019] [Indexed: 01/05/2023]
Abstract
Epilepsy is one of the most common brain disorders, which can be caused by abnormal synaptic transmissions. Many epilepsy-related mutations have been identified in synaptic ion channels, which are main targets for current antiepileptic drugs. One of the novel potential targets for therapy of epilepsy is a class of non-ion channel-type epilepsy-related proteins. The leucine-rich repeat glioma-inactivated protein 1 (LGI1) is a neuronal secreted protein, and has been extensively studied as a product of a causative gene for autosomal dominant lateral temporal lobe epilepsy (ADLTE; also known as autosomal dominant partial epilepsy with auditory features [ADPEAF]). At least 43 mutations of LGI1 have been found in ADLTE families. Additionally, autoantibodies against LGI1 in limbic encephalitis are associated with amnesia, seizures, and cognitive dysfunction. Although the relationship of LGI1 with synaptic transmission and synaptic disorders has been studied genetically, biochemically, and clinically, the structural mechanism of LGI1 remained largely unknown until recently. In this review, we introduce insights into pathogenic mechanisms of LGI1 from recent structural studies on LGI1 and its receptor, ADAM22. We also discuss the mechanism for pathogenesis of autoantibodies against LGI1, and the potential of chemical correctors as novel drugs for epilepsy, with structural aspects of LGI1-ADAM22.
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Affiliation(s)
- Atsushi Yamagata
- Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, 113-0032, Japan.
- Synchrotron Radiation Research Organization, The University of Tokyo, Tokyo, 113-0032, Japan.
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, 277-8561, Japan.
- Laboratory for Protein Functional and Structural Biology, RIKEN Center for Biosystems Dynamics Research, Yokohama, Kanagawa, 230-0045, Japan.
| | - Shuya Fukai
- Institute for Quantitative Biosciences, The University of Tokyo, Tokyo, 113-0032, Japan.
- Synchrotron Radiation Research Organization, The University of Tokyo, Tokyo, 113-0032, Japan.
- Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo, Chiba, 277-8561, Japan.
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Marin MA, Carmichael ST. Mechanisms of demyelination and remyelination in the young and aged brain following white matter stroke. Neurobiol Dis 2019; 126:5-12. [DOI: 10.1016/j.nbd.2018.07.023] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 07/03/2018] [Accepted: 07/18/2018] [Indexed: 01/01/2023] Open
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The Nogo Receptor Ligand LGI1 Regulates Synapse Number and Synaptic Activity in Hippocampal and Cortical Neurons. eNeuro 2018; 5:eN-NWR-0185-18. [PMID: 30225353 PMCID: PMC6140115 DOI: 10.1523/eneuro.0185-18.2018] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 07/31/2018] [Accepted: 08/14/2018] [Indexed: 12/20/2022] Open
Abstract
Leucine-rich glioma-inactivated protein 1 (LGI1) is a secreted neuronal protein and a Nogo receptor 1 (NgR1) ligand. Mutations in LGI1 in humans causes autosomal dominant lateral temporal lobe epilepsy and homozygous deletion of LGI1 in mice results in severe epileptic seizures that cause early postnatal death. NgR1 plays an important role in the development of CNS synapses and circuitry by limiting plasticity in the adult cortex via the activation of RhoA. These relationships and functions prompted us to examine the effect of LGI1 on synapse formation in vitro and in vivo. We report that application of LGI1 increases synaptic density in neuronal culture and that LGI1 null hippocampus has fewer dendritic mushroom spines than in wild-type (WT) littermates. Further, our electrophysiological investigations demonstrate that LGI1 null hippocampal neurons possess fewer and weaker synapses. RhoA activity is significantly increased in cortical cultures derived from LGI1 null mice and using a reconstituted system; we show directly that LGI1 antagonizes NgR1-tumor necrosis factor receptor orphan Y (TROY) signaling. Our data suggests that LGI1 enhances synapse formation in cortical and hippocampal neurons by reducing NgR1 signaling.
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Xie YJ, Zhou L, Wang Y, Jiang NW, Cao S, Shao CY, Wang XT, Li XY, Shen Y, Zhou L. Leucine-Rich Glioma Inactivated 1 Promotes Oligodendrocyte Differentiation and Myelination via TSC-mTOR Signaling. Front Mol Neurosci 2018; 11:231. [PMID: 30034322 PMCID: PMC6043672 DOI: 10.3389/fnmol.2018.00231] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 06/12/2018] [Indexed: 12/26/2022] Open
Abstract
Leucine-rich glioma inactivated 1 (Lgi1), a putative tumor suppressor, is tightly associated with autosomal dominant lateral temporal lobe epilepsy (ADLTE). It has been shown that Lgi1 regulates the myelination of Schwann cells in the peripheral nervous system (PNS). However, the function and underlying mechanisms for Lgi1 regulation of oligodendrocyte differentiation and myelination in the central nervous system (CNS) remain elusive. In addition, whether Lgi1 is required for myelin maintenance is unknown. Here, we show that Lgi1 is necessary and sufficient for the differentiation of oligodendrocyte precursor cells and is also required for the maintenance of myelinated fibers. The hypomyelination in Lgi1-/- mice attributes to the inhibition of the biosynthesis of lipids and proteins in oligodendrocytes (OLs). Moreover, we found that Lgi1 deficiency leads to a decrease in expression of tuberous sclerosis complex 1 (TSC1) and activates mammalian target of rapamycin signaling. Together, the present work establishes that Lgi1 is a regulator of oligodendrocyte development and myelination in CNS.
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Affiliation(s)
- Ya-Jun Xie
- Key Laboratory of Medical Neurobiology of Ministry of Health, Department of Neurobiology, Zhejiang University School of MedicineHangzhou, China
| | - Lin Zhou
- Key Laboratory of Medical Neurobiology of Ministry of Health, Department of Neurobiology, Zhejiang University School of MedicineHangzhou, China
| | - Yin Wang
- Laboratory of Craniocerebral Diseases of Ningxia Hui Autonomous Region, Ningxia Medical UniversityYinchuan, China
| | - Nan-Wei Jiang
- Ningbo Key Laboratory of Behavioral Neuroscience, Department of Physiology and Pharmacology, Ningbo University School of MedicineNingbo, China
| | - Shenglong Cao
- Department of Neurosurgery, Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou, China
| | - Chong-Yu Shao
- Key Laboratory of Medical Neurobiology of Ministry of Health, Department of Neurobiology, Zhejiang University School of MedicineHangzhou, China
| | - Xin-Tai Wang
- Key Laboratory of Medical Neurobiology of Ministry of Health, Department of Neurobiology, Zhejiang University School of MedicineHangzhou, China
| | - Xiang-Yao Li
- Key Laboratory of Medical Neurobiology of Ministry of Health, Department of Neurobiology, Zhejiang University School of MedicineHangzhou, China
| | - Ying Shen
- Key Laboratory of Medical Neurobiology of Ministry of Health, Department of Neurobiology, Zhejiang University School of MedicineHangzhou, China
| | - Liang Zhou
- Key Laboratory of Medical Neurobiology of Ministry of Health, Department of Neurobiology, Zhejiang University School of MedicineHangzhou, China
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Clinical characteristics and short-term prognosis of LGI1 antibody encephalitis: a retrospective case study. BMC Neurol 2018; 18:96. [PMID: 29980179 PMCID: PMC6035422 DOI: 10.1186/s12883-018-1099-z] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 07/02/2018] [Indexed: 01/17/2023] Open
Abstract
Background Recently, most reports of Leucine-rich glioma-inactivated 1 (LGI1) antibody encephalitis are from Europe and the US, while the short term outcome and clinical characteristics of Chinese patients are rarely reported,we study the clinical manifestations, laboratory results and brain magnetic resonance images (MRI) of eight patients who were recently diagnosed with LGI1 antibody encephalitis in our hospital to improve the awareness and knowledge of this disease. Methods Eight patients (five males and three females; mean age, 63.4) with LGI1 antibody encephalitis who were diagnosed and treated in the Department of Neurology of Shengjing Hospital of China Medical University from September 2016 to June 2017 were recruited for the current study. Their general information, clinical manifestations, treatment regimens, and short-term prognoses were retrospectively analyzed, as were the results from MRI and laboratory findings. Results Overall, patient symptoms included cognitive impairment, which manifested primarily as memory deficits (8/8), seizures (including faciobrachial dystonic seizure, (FBDS)) (8/8), psychiatric and behavioral disorders (7/8), sleep disorders (4/8), and autonomic abnormalities (3/8). Five patients also had abnormal findings on brain MRI, mainly involving the hippocampus, basal ganglia and insula. Hyponatremia occurred in six cases. All patients tested positive for LGI1 antibodies in their serum/cerebrospinal fluid (CSF)and patients were negative for tumors. Symptoms rapidly improved after treatment with immunoglobulin and/or steroid therapy. The patients were followed up for 4–13 months after discharge, and two patients relapsed. Conclusion Primary symptoms of LGI1 antibody encephalitis include memory impairments, seizures, FBDS, and mental and behavioral abnormalities. Increased titers of LGI1 antibodies are also present in the serum/CSF of patients. Patients often have hyponatremia, and MRIs show abnormalities in various brain regions. Finally, immunotherapy shows good efficacy and positive benefits, although patients may relapse in the short-term.
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Zhou L, Zhou L, Su LD, Cao SL, Xie YJ, Wang N, Shao CY, Wang YN, Zhou JH, Cowell JK, Shen Y. Celecoxib Ameliorates Seizure Susceptibility in Autosomal Dominant Lateral Temporal Epilepsy. J Neurosci 2018; 38:3346-3357. [PMID: 29491011 PMCID: PMC5884462 DOI: 10.1523/jneurosci.3245-17.2018] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 01/24/2018] [Accepted: 02/20/2018] [Indexed: 12/11/2022] Open
Abstract
Autosomal dominant lateral temporal epilepsy (ADLTE) is an inherited syndrome caused by mutations in the leucine-rich glioma inactivated 1 (LGI1) gene. It is known that glutamatergic transmission is altered in LGI1 mutant mice, and seizures can be reduced by restoring LGI1 function. Yet, the mechanism underlying ADLTE is unclear. Here, we propose that seizures in male LGI1-/- mice are due to nonsynaptic epileptiform activity in cortical neurons. We examined the intrinsic excitability of pyramidal neurons in the temporal cortex of male LGI1-/- mice and found that the voltage-gated K+ channel Kv1.2 was significantly downregulated. We also found that cytosolic phospholipase A2 (cPLA2)-cyclooxygenase 2 (Cox2) signaling was enhanced in LGI1-/- mice. Interestingly, Cox2 inhibition effectively restored the dysregulated Kv1.2 and reduced the intrinsic excitability of pyramidal neurons. Moreover, in vivo injection of celecoxib, an FDA-approved nonsteroidal anti-inflammatory drug, rescued the defective Kv1.2 (an ∼1.9-fold increase), thereby alleviating the seizure susceptibility and extending the life of LGI1-/- mice by 5 d. In summary, we conclude that LGI1 deficiency dysregulates cPLA2-Cox2 signaling to cause hyperexcitability of cortical pyramidal neurons, and celecoxib is a potential agent to manage human ADLTE.SIGNIFICANCE STATEMENT Haploinsufficiency of the leucine-rich glioma inactivated 1 (LGI1) gene is the major pathogenic basis for ADLTE, an inherited syndrome with no cure to date. Existing studies suggest that altered glutamatergic transmission in the hippocampus causes this disease, but the data are paradoxical. We demonstrate that the loss of LGI1 decreases Kv1.2 expression, enhances intrinsic excitability, and thereby causes epilepsy. Interestingly, for the first time, we show that an FDA-approved drug, celecoxib, rescues the Kv1.2 defect and alleviates seizure susceptibility in LGI1-/- mice, as well as improving their survival. Thus, we suggest that celecoxib is a promising drug for the treatment of ADLTE patients.
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Affiliation(s)
- Lin Zhou
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Liang Zhou
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou 310058, China
| | | | - Sheng-Long Cao
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou 310058, China
- Department of Neurosurgery, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou 310009, China
| | - Ya-Jun Xie
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Na Wang
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou 310058, China
- School of Medicine, Zhejiang University City College, Hangzhou 310015, China, and
| | - Chong-Yu Shao
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Ya-Nan Wang
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Jia-Huan Zhou
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - John K Cowell
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou 310058, China
- GRU Cancer Center, Augusta University, Augusta, Georgia 30912
| | - Ying Shen
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of Zhejiang Province, Zhejiang University School of Medicine, Hangzhou 310058, China,
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Smedfors G, Olson L, Karlsson TE. A Nogo-Like Signaling Perspective from Birth to Adulthood and in Old Age: Brain Expression Patterns of Ligands, Receptors and Modulators. Front Mol Neurosci 2018. [PMID: 29520216 PMCID: PMC5827527 DOI: 10.3389/fnmol.2018.00042] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
An appropriate strength of Nogo-like signaling is important to maintain synaptic homeostasis in the CNS. Disturbances have been associated with schizophrenia, MS and other diseases. Blocking Nogo-like signaling may improve recovery after spinal cord injury, stroke and traumatic brain injury. To understand the interacting roles of an increasing number of ligands, receptors and modulators engaged in Nogo-like signaling, the transcriptional activity of these genes in the same brain areas from birth to old age in the normal brain is needed. Thus, we have quantitatively mapped the innate expression of 11 important genes engaged in Nogo-like signaling. Using in situ hybridization, we located and measured the amount of mRNA encoding Nogo-A, OMgp, NgR1, NgR2, NgR3, Lingo-1, Troy, Olfactomedin, LgI1, ADAM22, and MAG, in 18 different brain areas at six different ages (P0, 1, 2, 4, 14, and 104 weeks). We show gene- and area-specific activities and how the genes undergo dynamic regulation during postnatal development and become stable during adulthood. Hippocampal areas underwent the largest changes over time. We only found differences between individual cortical areas in Troy and MAG. Subcortical areas presented the largest inter-regional differences; lateral and basolateral amygdala had markedly higher expression than other subcortical areas. The widespread differences and unique expression patterns of the different genes involved in Nogo-like signaling suggest that the functional complexes could look vastly different in different areas.
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Affiliation(s)
| | - Lars Olson
- Department of Neuroscience, Karolinska Institute, Stockholm, Sweden
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Abstract
Research in the last two decades has identified many synaptic organizers in the central nervous system that directly regulate the assembly of pre- and/or postsynaptic molecules, such as synaptic vesicles, active zone proteins, and neurotransmitter receptors. They are classified into secreted factors and cell adhesion molecules, such as neurexins and neuroligins. Certain secreted factors are termed extracellular scaffolding proteins (ESPs) because they are components of the synaptic extracellular matrix and serve as a scaffold at the synaptic cleft. These include Lgi1, Cbln1, neuronal pentraxins, Hevin, thrombospondins, and glypicans. Diffusible secreted factors, such as Wnts, fibroblast growth factors, and semaphorins, tend to act from a distance. In contrast, ESPs remain at the synaptic cleft and often help synaptic adhesion and/or accumulation of postsynaptic receptors. Many fundamental questions remain about when, how, and why various synaptic organizers establish and modify the vast numbers of connections during development and throughout life.
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Affiliation(s)
- Michisuke Yuzaki
- Department of Physiology, Keio University School of Medicine, Tokyo 160-8582, Japan;
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LGI1 tunes intrinsic excitability by regulating the density of axonal Kv1 channels. Proc Natl Acad Sci U S A 2017; 114:7719-7724. [PMID: 28673977 DOI: 10.1073/pnas.1618656114] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Autosomal dominant epilepsy with auditory features results from mutations in leucine-rich glioma-inactivated 1 (LGI1), a soluble glycoprotein secreted by neurons. Animal models of LGI1 depletion display spontaneous seizures, however, the function of LGI1 and the mechanisms by which deficiency leads to epilepsy are unknown. We investigated the effects of pure recombinant LGI1 and genetic depletion on intrinsic excitability, in the absence of synaptic input, in hippocampal CA3 neurons, a classical focus for epileptogenesis. Our data indicate that LGI1 is expressed at the axonal initial segment and regulates action potential firing by setting the density of the axonal Kv1.1 channels that underlie dendrotoxin-sensitive D-type potassium current. LGI1 deficiency incurs a >50% down-regulation of the expression of Kv1.1 and Kv1.2 via a posttranscriptional mechanism, resulting in a reduction in the capacity of axonal D-type current to limit glutamate release, thus contributing to epileptogenesis.
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Wang L, Yu C, Wang J, Leung P, Ma D, Zhao H, Taylor JSH, Chan SO. Nogo-B is the major form of Nogo at the floor plate and likely mediates crossing of commissural axons in the mouse spinal cord. J Comp Neurol 2017; 525:2915-2928. [DOI: 10.1002/cne.24246] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 05/06/2017] [Accepted: 05/13/2017] [Indexed: 11/09/2022]
Affiliation(s)
- Liqing Wang
- Department of Neurology; The Third Affiliated Hospital of Sun Yat-Sen University; Guangzhou Guangdong China
| | - Chao Yu
- Center of Health Examination, The Third Affiliated Hospital of Sun Yat-Sen University; Guangzhou Guangdong China
| | - Jun Wang
- Department of Anatomy and Embryology; School of Basic Medical Sciences, Peking University; Beijing China
| | - Peggy Leung
- School of Biomedical Sciences; The Chinese University of Hong Kong, Shatin, N.T.; Hong Kong China
| | - Ding Ma
- School of Biomedical Sciences; The Chinese University of Hong Kong, Shatin, N.T.; Hong Kong China
| | - Hui Zhao
- School of Biomedical Sciences; The Chinese University of Hong Kong, Shatin, N.T.; Hong Kong China
| | - Jeremy S. H. Taylor
- Department of Physiology; Anatomy and Genetics, University of Oxford; Oxford United Kingdom
| | - Sun-On Chan
- School of Biomedical Sciences; The Chinese University of Hong Kong, Shatin, N.T.; Hong Kong China
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Karlsson TE, Wellfelt K, Olson L. Spatiotemporal and Long Lasting Modulation of 11 Key Nogo Signaling Genes in Response to Strong Neuroexcitation. Front Mol Neurosci 2017; 10:94. [PMID: 28442990 PMCID: PMC5386981 DOI: 10.3389/fnmol.2017.00094] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 03/20/2017] [Indexed: 12/13/2022] Open
Abstract
Inhibition of nerve growth and plasticity in the CNS is to a large part mediated by Nogo-like signaling, now encompassing a plethora of ligands, receptors, co-receptors and modulators. Here we describe the distribution and levels of mRNA encoding 11 key genes involved in Nogo-like signaling (Nogo-A, Oligodendrocyte-Myelin glycoprotein (OMgp), Nogo receptor 1 (NgR1), NgR2, NgR3, Lingo-1, TNF receptor orphan Y (Troy), Olfactomedin, Lateral olfactory tract usher substance (Lotus) and membrane-type matrix metalloproteinase-3 (MT3-MPP)), as well as BDNF and GAPDH. Expression was analyzed in nine different brain areas before, and at eight time points during the first 3 days after a strong neuroexcitatory stimulation, caused by one kainic acid injection. A temporo-spatial pattern of orderly transcriptional regulations emerges that strengthens the role of Nogo-signaling mechanisms for synaptic plasticity in synchrony with transcriptional increases of BDNF mRNA. For most Nogo-type signaling genes, the largest alterations of mRNA levels occur in the dentate gyrus, with marked alterations also in the CA1 region. Changes occurred somewhat later in several areas of the cerebral cortex. The detailed spatio-temporal pattern of mRNA presence and kainic acid-induced transcriptional response is gene-specific. We reveal that several different gene alterations combine to decrease (and later increase) Nogo-like signaling, as expected to allow structural plasticity responses. Other genes are altered in the opposite direction, suggesting that the system prepares in advance in order to rapidly restore balance. However, the fact that Lingo-1 shows a seemingly opposite, plasticity inhibiting response to kainic acid (strong increase of mRNA in the dentate gyrus), may instead suggest a plasticity-enhancing intracellular function of this presumed NgR1 co-receptor.
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Affiliation(s)
| | - Katrin Wellfelt
- Department of Neuroscience, Karolinska InstitutetStockholm, Sweden
| | - Lars Olson
- Department of Neuroscience, Karolinska InstitutetStockholm, Sweden
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Nogo receptor blockade overcomes remyelination failure after white matter stroke and stimulates functional recovery in aged mice. Proc Natl Acad Sci U S A 2016; 113:E8453-E8462. [PMID: 27956620 DOI: 10.1073/pnas.1615322113] [Citation(s) in RCA: 89] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
White matter stroke is a distinct stroke subtype, accounting for up to 25% of stroke and constituting the second leading cause of dementia. The biology of possible tissue repair after white matter stroke has not been determined. In a mouse stroke model, white matter ischemia causes focal damage and adjacent areas of axonal myelin disruption and gliosis. In these areas of only partial damage, local white matter progenitors respond to injury, as oligodendrocyte progenitors (OPCs) proliferate. However, OPCs fail to mature into oligodendrocytes (OLs) even in regions of demyelination with intact axons and instead divert into an astrocytic fate. Local axonal sprouting occurs, producing an increase in unmyelinated fibers in the corpus callosum. The OPC maturation block after white matter stroke is in part mediated via Nogo receptor 1 (NgR1) signaling. In both aged and young adult mice, stroke induces NgR1 ligands and down-regulates NgR1 inhibitors during the peak OPC maturation block. Nogo ligands are also induced adjacent to human white matter stroke in humans. A Nogo signaling blockade with an NgR1 antagonist administered after stroke reduces the OPC astrocytic transformation and improves poststroke oligodendrogenesis in mice. Notably, increased white matter repair in aged mice is translated into significant poststroke motor recovery, even when NgR1 blockade is provided during the chronic time points of injury. These data provide a perspective on the role of NgR1 ligand function in OPC fate in the context of a specific and common type of stroke and show that it is amenable to systemic intervention to promote recovery.
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Thomas RA, Ambalavanan A, Rouleau GA, Barker PA. Identification of genetic variants of LGI1 and RTN4R (NgR1) linked to schizophrenia that are defective in NgR1-LGI1 signaling. Mol Genet Genomic Med 2016; 4:447-56. [PMID: 27468420 PMCID: PMC4947863 DOI: 10.1002/mgg3.215] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 02/17/2016] [Accepted: 02/19/2016] [Indexed: 12/29/2022] Open
Abstract
Background The protein NgR1 is encoded by RTN4R, a gene linked to schizophrenia. We previously reported NgR1 as receptor for the epilepsy‐linked protein LGI1. NgR1 regulates synapse number and synaptic plasticity, whereas LGI1 antagonizes NgR1 signaling and promotes synapse formation. Impairments in synapse formation are common in neurological disease and we hypothesized that an LGI1–NgR1 signaling pathway may contribute to the development of schizophrenia. Methods We screened two unrelated schizophrenic populations for variants in RTN4R and LGI1 using whole exome sequencing and Sanger sequencing. We tested the ability of LGI1 to bind rare coding variants of NgR1 using a cell surface binding assays and the signaling ability of NgR1 using COS7 cell‐spreading assays. Results We observed a previously reported rare coding variant in RTN4R (c.1195C>T, pR399W). We report the first LGI1 mutations to be identified in individuals with schizophrenia. Three different LGI1 mutations were found, two missense mutations (c.205G>A, p.V69I) and (c.313G>A, V105M), and an intronic variant (g.897T>C) that likely leads to a protein truncation. We found NgR1R119W and NgR1277C have a reduced ability to bind LGI1 in a cell surface binding assay. COS7 cell‐spreading assays reveal that NgR1 mutants are impaired in their ability to mediate RhoA activation. Conclusion Variants in NgR1 and LGI1 may be associated with schizophrenia and variants in NgR1 found in schizophrenic patients have impaired LGI1–NgR1 signaling. Impaired LGI1–NgR1 signaling may contribute to disease progression.
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Affiliation(s)
- Rhalena A Thomas
- Department of Neurology and Neurosurgery Montreal Neurological Institute McGill University 3801 University Montreal Quebec H3A 2B4 Canada
| | - Amirthagowri Ambalavanan
- Department of Human Genetics McGill University 1205 Dr Penfield Avenue Montreal Quebec H3A 1B1 Canada
| | - Guy A Rouleau
- Department of Neurology and NeurosurgeryMontreal Neurological InstituteMcGill University3801 UniversityMontrealQuebecH3A 2B4Canada; Department of Human GeneticsMcGill University1205 Dr Penfield AvenueMontrealQuebecH3A 1B1Canada
| | - Philip A Barker
- Department of Neurology and NeurosurgeryMontreal Neurological InstituteMcGill University3801 UniversityMontrealQuebecH3A 2B4Canada; Department of BiologyUniversity of British ColumbiaKelownaBC. V1V 1V7Canada
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LGI1 acts presynaptically to regulate excitatory synaptic transmission during early postnatal development. Sci Rep 2016; 6:21769. [PMID: 26878798 PMCID: PMC4754946 DOI: 10.1038/srep21769] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 02/01/2016] [Indexed: 12/30/2022] Open
Abstract
The secreted leucine-rich glioma inactivated 1 (LGI1) protein is an important actor for human seizures of both genetic and autoimmune etiology: mutations in LGI1 cause inherited temporal lobe epilepsy, while LGI1 is involved in antibody-mediated encephalitis. Remarkably, Lgi1-deficient (Lgi1(-/-)) mice recapitulate the epileptic disorder and display early-onset spontaneous seizures. To understand how Lgi1-deficiency leads to seizures during postnatal development, we here investigated the early functional and structural defects occurring before seizure onset in Lgi1(-/-) mice. We found an increased excitatory synaptic transmission in hippocampal slices from Lgi1(-/-) mice. No structural alteration in the morphology of pyramidal cell dendrites and synapses was observed at this stage, indicating that Lgi1-deficiency is unlikely to trigger early developmental abnormalities. Consistent with the presynaptic subcellular localization of the protein, Lgi1-deficiency caused presynaptic defects, with no alteration in postsynaptic AMPA receptor activity in Lgi1-/- pyramidal cells before seizure onset. Presynaptic dysfunction led to increased synaptic glutamate levels, which were associated with hyperexcitable neuronal networks. Altogether, these data show that Lgi1 acts presynaptically as a negative modulator of excitatory synaptic transmission during early postnatal development. We therefore here reveal that increased presynaptic glutamate release is a key early event resulting from Lgi1-deficiency, which likely contributes to epileptogenesis.
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Boillot M, Baulac S. Genetic models of focal epilepsies. J Neurosci Methods 2016; 260:132-43. [DOI: 10.1016/j.jneumeth.2015.06.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Revised: 06/03/2015] [Accepted: 06/04/2015] [Indexed: 01/06/2023]
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Eckharter C, Junker N, Winter L, Fischer I, Fogli B, Kistner S, Pfaller K, Zheng B, Wiche G, Klimaschewski L, Schweigreiter R. Schwann Cell Expressed Nogo-B Modulates Axonal Branching of Adult Sensory Neurons Through the Nogo-B Receptor NgBR. Front Cell Neurosci 2015; 9:454. [PMID: 26635533 PMCID: PMC4655273 DOI: 10.3389/fncel.2015.00454] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Accepted: 11/05/2015] [Indexed: 11/13/2022] Open
Abstract
In contrast to the central nervous system (CNS) nerve fibers do regenerate in the peripheral nervous system (PNS) although in a clinically unsatisfying manner. A major problem is excessive sprouting of regenerating axons which results in aberrant reinnervation of target tissue and impaired functional recovery. In the CNS, the reticulon protein Nogo-A has been identified as a prominent oligodendrocyte expressed inhibitor of long-distance growth of regenerating axons. We show here that the related isoform Nogo-B is abundantly expressed in Schwann cells in the PNS. Other than Nogo-A in oligodendrocytes, Nogo-B does not localize to the myelin sheath but is detected in the ER and the plasma membrane of Schwann cells. Adult sensory neurons that are cultured on nogo-a/b deficient Schwann cells form significantly fewer axonal branches vs. those on wildtype Schwann cells, while their maximal axonal extension is unaffected. We demonstrate that this effect of Nogo-B on neuronal morphology is restricted to undifferentiated Schwann cells and is mediated by direct physical contact between these two cell types. Moreover, we show that blocking the Nogo-B specific receptor NgBR, which we find expressed on sensory neurons and to interact with Schwann cell expressed Nogo-B, produces the same branching phenotype as observed after deletion of Nogo-B. These data provide evidence for a novel function of the nogo gene that is implemented by the Nogo-B isoform. The remarkably specific effects of Nogo-B/NgBR on axonal branching, while leaving axonal extension unaffected, are of potential clinical relevance in the context of excessive axonal sprouting after peripheral nerve injury.
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Affiliation(s)
- Christoph Eckharter
- Division of Neurobiochemistry, Biocenter, Innsbruck Medical University Innsbruck, Austria
| | - Nina Junker
- Division of Neurobiochemistry, Biocenter, Innsbruck Medical University Innsbruck, Austria
| | - Lilli Winter
- Max F. Perutz Laboratories, Department of Biochemistry and Cell Biology, University of Vienna Vienna, Austria
| | - Irmgard Fischer
- Max F. Perutz Laboratories, Department of Biochemistry and Cell Biology, University of Vienna Vienna, Austria
| | - Barbara Fogli
- Department of Anatomy, Histology and Embryology, Division of Neuroanatomy, Innsbruck Medical University Innsbruck, Austria
| | - Steffen Kistner
- Division of Neurobiochemistry, Biocenter, Innsbruck Medical University Innsbruck, Austria
| | - Kristian Pfaller
- Department of Anatomy, Histology and Embryology, Division of Histology and Embryology, Innsbruck Medical University Innsbruck, Austria
| | - Binhai Zheng
- Department of Neurosciences and Biomedical Sciences Graduate Program, School of Medicine, University of California, San Diego La Jolla, CA, USA
| | - Gerhard Wiche
- Max F. Perutz Laboratories, Department of Biochemistry and Cell Biology, University of Vienna Vienna, Austria
| | - Lars Klimaschewski
- Department of Anatomy, Histology and Embryology, Division of Neuroanatomy, Innsbruck Medical University Innsbruck, Austria
| | - Rüdiger Schweigreiter
- Division of Neurobiochemistry, Biocenter, Innsbruck Medical University Innsbruck, Austria
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26
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Stephany CÉ, Frantz MG, McGee AW. Multiple Roles for Nogo Receptor 1 in Visual System Plasticity. Neuroscientist 2015; 22:653-666. [PMID: 26552866 DOI: 10.1177/1073858415614564] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
During the developmental critical period for visual plasticity, discordant vision alters the responsiveness of neurons in visual cortex. The subsequent closure of the critical period not only consolidates neural function but also limits recovery of acuity from preceding abnormal visual experience. Despite species-specific differences in circuitry of the visual system, these characteristics are conserved. The nogo-66 receptor 1 (ngr1) is one of only a small number of genes identified thus far that is essential to closing the critical period. Mice lacking a functional ngr1 gene retain developmental visual plasticity as adults and their visual acuity spontaneously improves after prolonged visual deprivation. Experiments employing conditional mouse genetics have revealed that ngr1 restricts plasticity within distinct circuits for ocular dominance and visual acuity. However, the mechanisms by which NgR1 limits plasticity have not been elucidated, in part because the subcellular localization and signal transduction of the protein are only partially understood. Here we explore potential mechanisms for NgR1 function in relation to manipulations that reactivate visual plasticity in adults and propose lines of investigation to address relevant gaps in knowledge.
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Affiliation(s)
- Céleste-Élise Stephany
- Developmental Neuroscience Program, Saban Research Institute, Children's Hospital Los Angeles, Department of Pediatrics, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Michael G Frantz
- Developmental Neuroscience Program, Saban Research Institute, Children's Hospital Los Angeles, Department of Pediatrics, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
| | - Aaron W McGee
- Developmental Neuroscience Program, Saban Research Institute, Children's Hospital Los Angeles, Department of Pediatrics, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA
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27
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Correale J, Farez MF. The Role of Astrocytes in Multiple Sclerosis Progression. Front Neurol 2015; 6:180. [PMID: 26347709 PMCID: PMC4539519 DOI: 10.3389/fneur.2015.00180] [Citation(s) in RCA: 175] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2015] [Accepted: 08/03/2015] [Indexed: 01/03/2023] Open
Abstract
Multiple sclerosis (MS) is an inflammatory disorder causing central nervous system (CNS) demyelination and axonal injury. Although its etiology remains elusive, several lines of evidence support the concept that autoimmunity plays a major role in disease pathogenesis. The course of MS is highly variable; nevertheless, the majority of patients initially present a relapsing–remitting clinical course. After 10–15 years of disease, this pattern becomes progressive in up to 50% of untreated patients, during which time clinical symptoms slowly cause constant deterioration over a period of many years. In about 15% of MS patients, however, disease progression is relentless from disease onset. Published evidence supports the concept that progressive MS reflects a poorly understood mechanism of insidious axonal degeneration and neuronal loss. Recently, the type of microglial cell and of astrocyte activation and proliferation observed has suggested contribution of resident CNS cells may play a critical role in disease progression. Astrocytes could contribute to this process through several mechanisms: (a) as part of the innate immune system, (b) as a source of cytotoxic factors, (c) inhibiting remyelination and axonal regeneration by forming a glial scar, and (d) contributing to axonal mitochondrial dysfunction. Furthermore, regulatory mechanisms mediated by astrocytes can be affected by aging. Notably, astrocytes might also limit the detrimental effects of pro-inflammatory factors, while providing support and protection for oligodendrocytes and neurons. Because of the dichotomy observed in astrocytic effects, the design of therapeutic strategies targeting astrocytes becomes a challenging endeavor. Better knowledge of molecular and functional properties of astrocytes, therefore, should promote understanding of their specific role in MS pathophysiology, and consequently lead to development of novel and more successful therapeutic approaches.
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Affiliation(s)
- Jorge Correale
- Department of Neurology, Institute for Neurological Research Dr. Raúl Carrea, FLENI , Buenos Aires , Argentina
| | - Mauricio F Farez
- Department of Neurology, Institute for Neurological Research Dr. Raúl Carrea, FLENI , Buenos Aires , Argentina
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28
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Sui YP, Zhang XX, Lu JL, Sui F. New Insights into the Roles of Nogo-A in CNS Biology and Diseases. Neurochem Res 2015; 40:1767-85. [PMID: 26266872 DOI: 10.1007/s11064-015-1671-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Revised: 07/15/2015] [Accepted: 07/17/2015] [Indexed: 12/22/2022]
Abstract
Nogos have become a hot topic for its well-known number Nogo-A's big role in clinical matters. It has been recognized that the expression of Nogo-A and the receptor NgR1 inhibit the neuron's growth after CNS injuries or the onset of the MS. The piling evidence supports the notion that the Nogo-A is also involved in the synaptic plasticity, which was shown to negatively regulate the strength of synaptic transmission. The occurrence of significant schizophrenia-like behavioral phenotypes in Nogo-A KO rats also added strong proof to this conclusion. This review mainly focuses on the structure of Nogo-A and its corresponding receptor-NgR1, its intra- and extra-cellular signaling, together with its major physiological functions such as regulation of migration and distribution and its related diseases like stroke, AD, ALS and so on.
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Affiliation(s)
- Yun-Peng Sui
- Institute of Chinese Material Medica, China Academy of Chinese Medical Sciences, Beijing, 100700, China
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29
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The LGI1-ADAM22 protein complex directs synapse maturation through regulation of PSD-95 function. Proc Natl Acad Sci U S A 2015; 112:E4129-37. [PMID: 26178195 DOI: 10.1073/pnas.1511910112] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Synapse development is coordinated by a number of transmembrane and secreted proteins that come together to form synaptic organizing complexes. Whereas a variety of synaptogenic proteins have been characterized, much less is understood about the molecular networks that support the maintenance and functional maturation of nascent synapses. Here, we demonstrate that leucine-rich, glioma-inactivated protein 1 (LGI1), a secreted protein previously shown to modulate synaptic AMPA receptors, is a paracrine signal released from pre- and postsynaptic neurons that acts specifically through a disintegrin and metalloproteinase protein 22 (ADAM22) to set postsynaptic strength. We go on to describe a novel role for ADAM22 in maintaining excitatory synapses through PSD-95/Dlg1/zo-1 (PDZ) domain interactions. Finally, we show that in the absence of LGI1, the mature synapse scaffolding protein PSD-95, but not the immature synapse scaffolding protein SAP102, is unable to modulate synaptic transmission. These results indicate that LGI1 and ADAM22 form an essential synaptic organizing complex that coordinates the maturation of excitatory synapses by regulating the functional incorporation of PSD-95.
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30
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Pakozdy A, Patzl M, Zimmermann L, Jokinen TS, Glantschnigg U, Kelemen A, Hasegawa D. LGI Proteins and Epilepsy in Human and Animals. J Vet Intern Med 2015; 29:997-1005. [PMID: 26032921 PMCID: PMC4895363 DOI: 10.1111/jvim.12610] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2014] [Revised: 03/23/2015] [Accepted: 04/11/2015] [Indexed: 12/16/2022] Open
Abstract
Leucine‐rich glioma‐inactivated (LGI) protein was first thought to have a suppressor effect in the formation of some cancers. Developments in physiology and medicine made it possible to characterize the function of the LGI protein family and its crucial role in different conditions more precisely. These proteins play an important role in synaptic transmission, and dysfunction may cause hyperexcitability. Genetic mutation of LGI1was confirmed to be the cause of autosomal dominant lateral temporal lobe epilepsy in humans. The LGI2 mutation was identified in benign familial juvenile epilepsy in Lagotto Romagnolo (LR) dogs. Cats with familial spontaneous temporal lobe epilepsy have been reported, and the etiology might be associated with LGI protein family dysfunction. In addition, an autoimmune reaction against LGI1 was detected in humans and cats with limbic encephalitis. These advances prompted a review of LGI protein function and its role in different seizure disorders.
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Affiliation(s)
- A Pakozdy
- University Clinic of Small Animals, University of Veterinary Medicine, Vienna, Austria
| | - M Patzl
- Institute of Immunology, University of Veterinary Medicine, Vienna, Austria
| | - L Zimmermann
- Unit of Physiology and Biophysics, University of Veterinary Medicine, Vienna, Austria
| | - T S Jokinen
- Department of Equine and Small Animal Medicine, University of Helsinki, Helsinki, Finland
| | - U Glantschnigg
- University Clinic of Small Animals, University of Veterinary Medicine, Vienna, Austria
| | - A Kelemen
- Epilepsy Center, National Institute of Clinical Neurosciences, Budapest, Hungary
| | - D Hasegawa
- Department of Clinical Veterinary Medicine, Nippon Veterinary and Life Science University, Musashinoshi, Tokyo, Japan
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31
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Huijbers MG, Querol LA, Niks EH, Plomp JJ, van der Maarel SM, Graus F, Dalmau J, Illa I, Verschuuren JJ. The expanding field of IgG4-mediated neurological autoimmune disorders. Eur J Neurol 2015; 22:1151-61. [PMID: 26032110 DOI: 10.1111/ene.12758] [Citation(s) in RCA: 122] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Accepted: 04/27/2015] [Indexed: 12/13/2022]
Abstract
At least 13 different disease entities affecting the central nervous system, peripheral nervous system and connective tissue of the skin or kidneys are associated with immunoglobulin G4 (IgG4) immune reactivity. IgG4 has always been considered a benign, non-inflammatory subclass of IgG, in contrast to the well-known complement-activating pro-inflammatory IgG1 subclass. A comprehensive review of these IgG4 autoimmune disorders reveals striking similarities in epitope binding and human leukocyte antigen (HLA) associations. Mechanical interference of extracellular ligand-receptor interactions by the associated IgG4 antibodies seems to be the common/converging disease mechanism in these disorders.
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Affiliation(s)
- M G Huijbers
- Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands.,Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - L A Querol
- Department of Neurology, Hospital Santa Creu I Sant Pau, Barcelona, Spain
| | - E H Niks
- Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands
| | - J J Plomp
- Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands
| | - S M van der Maarel
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - F Graus
- Department of Neurology, Hospital Santa Creu I Sant Pau, Barcelona, Spain
| | - J Dalmau
- Department of Neurology, Hospital Santa Creu I Sant Pau, Barcelona, Spain
| | - I Illa
- Department of Neurology, Hospital Santa Creu I Sant Pau, Barcelona, Spain
| | - J J Verschuuren
- Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands
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32
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Xu YQ, Sun ZQ, Wang YT, Xiao F, Chen MW. Function of Nogo-A/Nogo-A receptor in Alzheimer's disease. CNS Neurosci Ther 2015; 21:479-85. [PMID: 25732725 DOI: 10.1111/cns.12387] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 01/01/2015] [Accepted: 01/02/2015] [Indexed: 12/11/2022] Open
Abstract
Nogo-A is a protein inhibiting axonal regeneration, which is considered a major obstacle to nerve regeneration after injury in mammals. Rapid progress has been achieved in new physiopathological function of Nogo-A in Alzheimer's disease in the past decade. Recent research shows that through binding to Nogo-A receptor, Nogo-A plays an important role in Alzheimer's disease (AD) pathogenesis. Particularly, Nogo-A/Nogo-A receptors modulate the generation of amyloid β-protein (Aβ), which is thought to be a major cause of AD. This review describes the recent development of Nogo-A, Nogo-A receptor, and downstream signaling involved in AD and pharmacological basis of therapeutic drugs. We concluded the Nogo-A/Nogo-A receptor provide new insight into potential mechanisms and promising therapy strategies in AD.
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Affiliation(s)
- Ying-Qi Xu
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, China
| | - Zhong-Qing Sun
- Department of Pharmacology, School of Medicine, Jinan University, Guangzhou, China
| | - Yi-Tao Wang
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, China
| | - Fei Xiao
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, China.,Department of Pharmacology, School of Medicine, Jinan University, Guangzhou, China
| | - Mei-Wan Chen
- State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau, China
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Xie YJ, Zhou L, Jiang N, Zhang N, Zou N, Zhou L, Wang Y, Cowell JK, Shen Y. Essential roles of leucine-rich glioma inactivated 1 in the development of embryonic and postnatal cerebellum. Sci Rep 2015; 5:7827. [PMID: 25591666 PMCID: PMC4296302 DOI: 10.1038/srep07827] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2014] [Accepted: 12/12/2014] [Indexed: 11/24/2022] Open
Abstract
Leucine-rich glioma inactivated 1 (LGI1) is a secreted protein that interacts with ADAM transmembrane proteins, and its mutations are linked to human epilepsy. The function of LGI1 in CNS development remains undefined. Here, we report novel functions of LGI1 in the generation of cerebellar granule precursors (CGPs) and differentiation of radial glial cells (RGCs) in the cerebellum. A reduction in external granule layer thickness and defects in foliation were seen in embryonic and new-born LGI1 knockout (KO) mice. BrdU staining showed an inhibited proliferation of CGPs in KO embryos, which might be explained by the reduced Sonic hedgehog in embryos. In addition, the differentiation of RGCs into Bergmann glias was suppressed in KO mice. Enhanced Jagged1-Notch1 signaling in KO mice via reduced β-secretase proteolysis suggests that altered phenotype of RGCs is due to abnormal Notch1 signaling. Together, our results demonstrate that LGI1 is an essential player in the cerebellar development.
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Affiliation(s)
- Ya-Jun Xie
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of the Ministry of Health, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Liang Zhou
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of the Ministry of Health, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Nanwei Jiang
- Zhejiang Provincial Key Laboratory of Pathophysiology, Department of Physiology and Pharmacology, Ningbo University School of Medicine, Ningbo, China
| | - Nan Zhang
- Ningxia Key Laboratory of Cerebrocranial Diseases, Ningxia Medical University, Yinchuan, China
| | - Na Zou
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of the Ministry of Health, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Lin Zhou
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of the Ministry of Health, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
| | - Yin Wang
- Ningxia Key Laboratory of Cerebrocranial Diseases, Ningxia Medical University, Yinchuan, China
| | - John K Cowell
- Georgia Regents University, Cancer Center, Augusta, GA, USA
| | - Ying Shen
- Department of Neurobiology, Key Laboratory of Medical Neurobiology of the Ministry of Health, Zhejiang Province Key Laboratory of Neurobiology, Zhejiang University School of Medicine, Hangzhou, China
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Su LD, Xie YJ, Zhou L, Shen Y, Hu YH. LGI1 is involved in the development of mouse brain. THE CEREBELLUM 2014; 14:12-4. [PMID: 25471260 DOI: 10.1007/s12311-014-0628-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Mutations in leucine-rich glioma inactivated 1 (LGI1) are linked to human autosomal dominant lateral temporal lobe epilepsy. It has been shown that LGI1 prevents the inactivation of voltage-gated potassium channels, mediates postnatal maturation of glutamatergic synapses, and regulates excitatory neurotransmission. However, other functions of LGI1 in the central nervous system have not been elucidated. We found that LGI1 is involved in the development of the cerebellum and cortex. The thickness of external granule layer was reduced, and foliation was affected in the cerebellum of LGI1 knockout mice. Double staining with Pax6 and BrdU showed a significant inhibition of proliferation of granule cell precursors of knockout embryos. The differentiation of radial glia cells was also suppressed in knockout mice, as shown by increased radial glial cells and decreased Bergmann glias in the areas of the cerebellum and cortex. Thus, our data demonstrate that LGI1 may be an essential player in the development of the brain.
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Affiliation(s)
- Li-Da Su
- Neuroscience Care Unit, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, People's Republic of China
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35
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Boillot M, Huneau C, Marsan E, Lehongre K, Navarro V, Ishida S, Dufresnois B, Ozkaynak E, Garrigue J, Miles R, Martin B, Leguern E, Anderson MP, Baulac S. Glutamatergic neuron-targeted loss of LGI1 epilepsy gene results in seizures. ACTA ACUST UNITED AC 2014; 137:2984-96. [PMID: 25234641 DOI: 10.1093/brain/awu259] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Leucin-rich, glioma inactivated 1 (LGI1) is a secreted protein linked to human seizures of both genetic and autoimmune aetiology. Mutations in the LGI1 gene are responsible for autosomal dominant temporal lobe epilepsy with auditory features, whereas LGI1 autoantibodies are involved in limbic encephalitis, an acquired epileptic disorder associated with cognitive impairment. We and others previously reported that Lgi1-deficient mice have early-onset spontaneous seizures leading to premature death at 2-3 weeks of age. Yet, where and when Lgi1 deficiency causes epilepsy remains unknown. To address these questions, we generated Lgi1 conditional knockout (cKO) mice using a set of universal Cre-driver mouse lines. Selective deletion of Lgi1 was achieved in glutamatergic pyramidal neurons during embryonic (Emx1-Lgi1cKO) or late postnatal (CaMKIIα-Lgi1cKO) developmental stages, or in gamma amino butyric acidergic (GABAergic) parvalbumin interneurons (PV-Lgi1cKO). Emx1-Lgi1cKO mice displayed early-onset and lethal seizures, whereas CaMKIIα-Lgi1cKO mice presented late-onset occasional seizures associated with variable reduced lifespan. In contrast, neither spontaneous seizures nor increased seizure susceptibility to convulsant were observed when Lgi1 was deleted in parvalbumin interneurons. Together, these data showed that LGI1 depletion restricted to pyramidal cells is sufficient to generate seizures, whereas seizure thresholds were unchanged after depletion in gamma amino butyric acidergic parvalbumin interneurons. We suggest that LGI1 secreted from excitatory neurons, but not parvalbumin inhibitory neurons, makes a major contribution to the pathogenesis of LGI1-related epilepsies. Our data further indicate that LGI1 is required from embryogenesis to adulthood to achieve proper circuit functioning.
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Affiliation(s)
- Morgane Boillot
- 1 INSERM, U 1127, F-75013, Paris, France 2 CNRS, UMR 7225, F-75013, Paris, France 3 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, ICM, F-75013 Paris, France 4 Institut du Cerveau et de la Moelle épinière (ICM), F-75013, Paris, France
| | - Clément Huneau
- 5 Université de Rennes 1, LTSI, F-35000, Rennes, France 6 INSERM, U1099, F-35000, Rennes, France
| | - Elise Marsan
- 1 INSERM, U 1127, F-75013, Paris, France 2 CNRS, UMR 7225, F-75013, Paris, France 3 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, ICM, F-75013 Paris, France 4 Institut du Cerveau et de la Moelle épinière (ICM), F-75013, Paris, France
| | - Katia Lehongre
- 1 INSERM, U 1127, F-75013, Paris, France 2 CNRS, UMR 7225, F-75013, Paris, France 3 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, ICM, F-75013 Paris, France 4 Institut du Cerveau et de la Moelle épinière (ICM), F-75013, Paris, France
| | - Vincent Navarro
- 1 INSERM, U 1127, F-75013, Paris, France 2 CNRS, UMR 7225, F-75013, Paris, France 3 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, ICM, F-75013 Paris, France 4 Institut du Cerveau et de la Moelle épinière (ICM), F-75013, Paris, France 7 AP-HP, Hôpital de la Pitié-Salpêtrière, Epilepsy Unit, F-75013, Paris, France
| | - Saeko Ishida
- 1 INSERM, U 1127, F-75013, Paris, France 2 CNRS, UMR 7225, F-75013, Paris, France 3 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, ICM, F-75013 Paris, France 4 Institut du Cerveau et de la Moelle épinière (ICM), F-75013, Paris, France
| | - Béatrice Dufresnois
- 1 INSERM, U 1127, F-75013, Paris, France 2 CNRS, UMR 7225, F-75013, Paris, France 3 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, ICM, F-75013 Paris, France 4 Institut du Cerveau et de la Moelle épinière (ICM), F-75013, Paris, France
| | - Ekim Ozkaynak
- 8 Departments of Neurology and Pathology, Beth Israel Deaconess Medical Centre and Harvard Medical School, Boston, Massachusetts 02215, USA
| | - Jérôme Garrigue
- 1 INSERM, U 1127, F-75013, Paris, France 2 CNRS, UMR 7225, F-75013, Paris, France 3 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, ICM, F-75013 Paris, France 4 Institut du Cerveau et de la Moelle épinière (ICM), F-75013, Paris, France
| | - Richard Miles
- 1 INSERM, U 1127, F-75013, Paris, France 2 CNRS, UMR 7225, F-75013, Paris, France 3 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, ICM, F-75013 Paris, France 4 Institut du Cerveau et de la Moelle épinière (ICM), F-75013, Paris, France
| | - Benoit Martin
- 5 Université de Rennes 1, LTSI, F-35000, Rennes, France 6 INSERM, U1099, F-35000, Rennes, France
| | - Eric Leguern
- 1 INSERM, U 1127, F-75013, Paris, France 2 CNRS, UMR 7225, F-75013, Paris, France 3 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, ICM, F-75013 Paris, France 4 Institut du Cerveau et de la Moelle épinière (ICM), F-75013, Paris, France 9 AP-HP, Hôpital de la Pitié-Salpêtrière, Département de Génétique et de Cytogénétique, F-75013, Paris, France
| | - Matthew P Anderson
- 8 Departments of Neurology and Pathology, Beth Israel Deaconess Medical Centre and Harvard Medical School, Boston, Massachusetts 02215, USA
| | - Stéphanie Baulac
- 1 INSERM, U 1127, F-75013, Paris, France 2 CNRS, UMR 7225, F-75013, Paris, France 3 Sorbonne Universités, UPMC Univ Paris 06, UMR S 1127, ICM, F-75013 Paris, France 4 Institut du Cerveau et de la Moelle épinière (ICM), F-75013, Paris, France
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Olivetti PR, Maheshwari A, Noebels JL. Neonatal estradiol stimulation prevents epilepsy in Arx model of X-linked infantile spasms syndrome. Sci Transl Med 2014; 6:220ra12. [PMID: 24452264 DOI: 10.1126/scitranslmed.3007231] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Infantile spasms are a catastrophic form of pediatric epilepsy with inadequate treatment. In patients, mutation of ARX, a transcription factor selectively expressed in neuronal precursors and adult inhibitory interneurons, impairs cell migration and causes a major inherited subtype of the disease X-linked infantile spasms syndrome. Using an animal model, the Arx((GCG)10+7) mouse, we determined that brief estradiol (E2) administration during early postnatal development prevented spasms in infancy and seizures in adult mutants. E2 was ineffective when delivered after puberty or 30 days after birth. Early E2 treatment altered mRNA levels of three downstream targets of Arx (Shox2, Ebf3, and Lgi1) and restored depleted interneuron populations without increasing GABAergic synaptic density. Postnatal E2 treatment may induce lasting transcriptional changes that lead to enduring disease modification and could potentially serve as a therapy for inherited interneuronopathies.
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Affiliation(s)
- Pedro R Olivetti
- Blue Bird Circle Developmental Neurogenetics Laboratory, Department of Neurology, Baylor College of Medicine, Houston, TX 77030, USA
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Kumari A, Thakur MK. Age-dependent decline of nogo-a protein in the mouse cerebrum. Cell Mol Neurobiol 2014; 34:1131-41. [PMID: 25078756 DOI: 10.1007/s10571-014-0088-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Accepted: 07/12/2014] [Indexed: 12/19/2022]
Abstract
Nogo-A, a myelin-associated neurite growth inhibitory protein, is implicated in synaptic plasticity. It binds to its receptor namely the Nogo-66 receptor1 (NgR1) and regulates filamentous (F) actin dynamics via small GTPases of the Rho family, RhoA kinase (ROCK), LimK and cofilin. These proteins are associated with the structural plasticity, one of the components of synaptic plasticity, which is known to decline with normal aging. So, the level of Nogo-A and its receptor NgR1 are likely to vary during normal brain aging. However, it is not clearly understood how the levels of Nogo-A and its receptor NgR1 change in the cerebrum during aging. Several studies show an age- and gender-dependent decline in synaptic plasticity. Therefore, the present study was planned to analyze the relative changes in the mRNA and protein levels of Nogo-A and NgR1 in both male and female mice cerebrum during normal aging. Western blot analysis has shown decrease in Nogo-A protein level during aging in both male and female mice cerebrum. This was further confirmed by immunofluorescence analysis. RT-PCR analysis of Nogo-A mRNA showed no significant difference in the above-mentioned groups. This was also supported by in situ hybridization. NgR1 protein and its mRNA expression levels showed no significant alteration with aging in the cerebrum of both male and female mice. Taken together, we speculate that the downregulation of Nogo-A protein might have a role in the altered synaptic plasticity during aging.
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Affiliation(s)
- Anita Kumari
- Biochemistry and Molecular Biology Laboratory, Department of Zoology, Banaras Hindu University, Varanasi, 221005, India
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Wick HC, Drabkin H, Ngu H, Sackman M, Fournier C, Haggett J, Blake JA, Bianchi DW, Slonim DK. DFLAT: functional annotation for human development. BMC Bioinformatics 2014; 15:45. [PMID: 24507166 PMCID: PMC3928322 DOI: 10.1186/1471-2105-15-45] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Accepted: 01/28/2014] [Indexed: 11/25/2022] Open
Abstract
Background Recent increases in genomic studies of the developing human fetus and neonate have led to a need for widespread characterization of the functional roles of genes at different developmental stages. The Gene Ontology (GO), a valuable and widely-used resource for characterizing gene function, offers perhaps the most suitable functional annotation system for this purpose. However, due in part to the difficulty of studying molecular genetic effects in humans, even the current collection of comprehensive GO annotations for human genes and gene products often lacks adequate developmental context for scientists wishing to study gene function in the human fetus. Description The Developmental FunctionaL Annotation at Tufts (DFLAT) project aims to improve the quality of analyses of fetal gene expression and regulation by curating human fetal gene functions using both manual and semi-automated GO procedures. Eligible annotations are then contributed to the GO database and included in GO releases of human data. DFLAT has produced a considerable body of functional annotation that we demonstrate provides valuable information about developmental genomics. A collection of gene sets (genes implicated in the same function or biological process), made by combining existing GO annotations with the 13,344 new DFLAT annotations, is available for use in novel analyses. Gene set analyses of expression in several data sets, including amniotic fluid RNA from fetuses with trisomies 21 and 18, umbilical cord blood, and blood from newborns with bronchopulmonary dysplasia, were conducted both with and without the DFLAT annotation. Conclusions Functional analysis of expression data using the DFLAT annotation increases the number of implicated gene sets, reflecting the DFLAT’s improved representation of current knowledge. Blinded literature review supports the validity of newly significant findings obtained with the DFLAT annotations. Newly implicated significant gene sets also suggest specific hypotheses for future research. Overall, the DFLAT project contributes new functional annotation and gene sets likely to enhance our ability to interpret genomic studies of human fetal and neonatal development.
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Affiliation(s)
- Heather C Wick
- Department of Computer Science, Tufts University, 155 College Ave, Medford, MA 02155, USA.
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39
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Baulac S. Genetics advances in autosomal dominant focal epilepsies. PROGRESS IN BRAIN RESEARCH 2014; 213:123-39. [DOI: 10.1016/b978-0-444-63326-2.00007-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Pitkänen A, Ndode-Ekane XE, Łukasiuk K, Wilczynski GM, Dityatev A, Walker MC, Chabrol E, Dedeurwaerdere S, Vazquez N, Powell EM. Neural ECM and epilepsy. PROGRESS IN BRAIN RESEARCH 2014; 214:229-62. [DOI: 10.1016/b978-0-444-63486-3.00011-6] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Abstract
Mutations in the LGI1 gene predispose to autosomal dominant lateral temporal lobe epilepsy, a rare hereditary form with incomplete penetrance and associated with acoustic auras. LGI1 is not a structural component of an ion channel like most epilepsy-related genes, but is a secreted protein. Mutant null mice exhibit early-onset seizures, and electrophysiological analysis shows abnormal synaptic transmission. LGI1 binds to ADAM23 on the presynaptic membrane and ADAM22 on the postsynaptic membrane, further implicating it in regulating the strength of synaptic transmission. Patients with limbic encephalitis show autoantibodies against LGI1 and develop seizures, supporting a role for LGI1 in synapse transmission in the post developmental brain. LGI1, however, also seems to be involved in aspects of neurite development and dendritic pruning, suggesting an additional role in corticogenesis. LGI1 is also involved in cell movement and suppression of dendritic outgrowth in in vitro systems, possibly involving actin cytoskeleton dynamics. Expression patterns in embryonic development correspond to areas of neuronal migration. Loss of LGI1 expression also impacts on myelination of the central and peripheral nervous systems. In zebrafish embryos, knockdown of lgi1a leads to a seizure-like behavior and abnormal brain development, providing a system to study its role in early embryogenesis. Despite being implicated in a role in both synapse transmission and neuronal development, how LGI1 predisposes to epilepsy is still largely unknown. It appears, however, that LGI1 may function differently in a cell context-specific manner, implying a complex involvement in brain development and function that remains to be defined.
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Affiliation(s)
- John K Cowell
- Georgia Regents University Cancer Center, Augusta, GA, USA.
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Ohkawa T, Fukata Y, Yamasaki M, Miyazaki T, Yokoi N, Takashima H, Watanabe M, Watanabe O, Fukata M. Autoantibodies to epilepsy-related LGI1 in limbic encephalitis neutralize LGI1-ADAM22 interaction and reduce synaptic AMPA receptors. J Neurosci 2013; 33:18161-74. [PMID: 24227725 PMCID: PMC3828467 DOI: 10.1523/jneurosci.3506-13.2013] [Citation(s) in RCA: 228] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Revised: 09/23/2013] [Accepted: 10/09/2013] [Indexed: 01/12/2023] Open
Abstract
More than 30 mutations in LGI1, a secreted neuronal protein, have been reported with autosomal dominant lateral temporal lobe epilepsy (ADLTE). Although LGI1 haploinsufficiency is thought to cause ADLTE, the underlying molecular mechanism that results in abnormal brain excitability remains mysterious. Here, we focused on a mode of action of LGI1 autoantibodies associated with limbic encephalitis (LE), which is one of acquired epileptic disorders characterized by subacute onset of amnesia and seizures. We comprehensively screened human sera from patients with immune-mediated neurological disorders for LGI1 autoantibodies, which also uncovered novel autoantibodies against six cell surface antigens including DCC, DPP10, and ADAM23. Our developed ELISA arrays revealed a specific role for LGI1 antibodies in LE and concomitant involvement of multiple antibodies, including LGI1 antibodies in neuromyotonia, a peripheral nerve disorder. LGI1 antibodies associated with LE specifically inhibited the ligand-receptor interaction between LGI1 and ADAM22/23 by targeting the EPTP repeat domain of LGI1 and reversibly reduced synaptic AMPA receptor clusters in rat hippocampal neurons. Furthermore, we found that disruption of LGI1-ADAM22 interaction by soluble extracellular domain of ADAM22 was sufficient to reduce synaptic AMPA receptors in rat hippocampal neurons and that levels of AMPA receptor were greatly reduced in the hippocampal dentate gyrus in the epileptic LGI1 knock-out mouse. Therefore, either genetic or acquired loss of the LGI1-ADAM22 interaction reduces the AMPA receptor function, causing epileptic disorders. These results suggest that by finely regulating the synaptic AMPA receptors, the LGI1-ADAM22 interaction maintains physiological brain excitability throughout life.
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Affiliation(s)
- Toshika Ohkawa
- Division of Membrane Physiology, Department of Cell Physiology, National Institute for Physiological Sciences (NIPS), Okazaki 444-8787, Japan
- Department of Physiological Sciences, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Okazaki 444-8787, Japan
| | - Yuko Fukata
- Division of Membrane Physiology, Department of Cell Physiology, National Institute for Physiological Sciences (NIPS), Okazaki 444-8787, Japan
- Department of Physiological Sciences, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Okazaki 444-8787, Japan
| | - Miwako Yamasaki
- Department of Anatomy, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
| | - Taisuke Miyazaki
- Department of Anatomy, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
| | - Norihiko Yokoi
- Division of Membrane Physiology, Department of Cell Physiology, National Institute for Physiological Sciences (NIPS), Okazaki 444-8787, Japan
- Department of Physiological Sciences, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Okazaki 444-8787, Japan
| | - Hiroshi Takashima
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Science, Kagoshima 890-8544, Japan; and
| | - Masahiko Watanabe
- Department of Anatomy, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
- Japan Science and Technology Agency, Core Research for Evolutional Science and Technology, Chiyoda-ku, Tokyo 102-0075, Japan
| | - Osamu Watanabe
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Science, Kagoshima 890-8544, Japan; and
| | - Masaki Fukata
- Division of Membrane Physiology, Department of Cell Physiology, National Institute for Physiological Sciences (NIPS), Okazaki 444-8787, Japan
- Department of Physiological Sciences, School of Life Science, The Graduate University for Advanced Studies (SOKENDAI), Okazaki 444-8787, Japan
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Seira O, Del Río JA. Glycogen synthase kinase 3 beta (GSK3β) at the tip of neuronal development and regeneration. Mol Neurobiol 2013; 49:931-44. [PMID: 24158777 DOI: 10.1007/s12035-013-8571-y] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Accepted: 10/10/2013] [Indexed: 12/31/2022]
Abstract
Gaining a basic understanding of the inhibitory molecules and the intracellular signaling involved in axon development and repulsion after neural lesions is of clear biomedical interest. In recent years, numerous studies have described new molecules and intracellular mechanisms that impair axonal outgrowth after injury. In this scenario, the role of glycogen synthase kinase 3 beta (GSK3β) in the axonal responses that occur after central nervous system (CNS) lesions began to be elucidated. GSK3β function in the nervous tissue is associated with neural development, neuron polarization, and, more recently, neurodegeneration. In fact, GSK3β has been considered as a putative therapeutic target for promoting functional recovery in injured or degenerative CNS. In this review, we summarize current understanding of the role of GSK3β during neuronal development and regeneration. In particular, we discuss GSK3β activity levels and their possible impact on cytoskeleton dynamics during both processes.
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Affiliation(s)
- Oscar Seira
- Molecular and Cellular Neurobiotechnology, Institute of Bioengineering of Catalonia (IBEC), University of Barcelona, Baldiri Reixac 15-21, 08028, Barcelona, Spain,
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Hacker DL, Kiseljak D, Rajendra Y, Thurnheer S, Baldi L, Wurm FM. Polyethyleneimine-based transient gene expression processes for suspension-adapted HEK-293E and CHO-DG44 cells. Protein Expr Purif 2013; 92:67-76. [PMID: 24021764 PMCID: PMC7129890 DOI: 10.1016/j.pep.2013.09.001] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Revised: 08/30/2013] [Accepted: 09/02/2013] [Indexed: 12/30/2022]
Abstract
A brief overview of principles of TGE using mammalian cells. Description of TGE processes for HEK293 and CHO cells. Description of orbitally shaken bioreactors for suspension cell cultivation. Description of polyethylenime-based transfection processes.
Transient gene expression (TGE) from mammalian cells is an increasingly important tool for the rapid production of recombinant proteins for research applications in biochemistry, structural biology, and biomedicine. Here we review methods for the transfection of human embryo kidney (HEK-293) and Chinese hamster ovary (CHO) cells in suspension culture using the cationic polymer polyethylenimine (PEI) for gene delivery.
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Affiliation(s)
- David L Hacker
- Protein Expression Core Facility, EPFL, CH-1015 Lausanne, Switzerland; Laboratory of Cellular Biotechnology, EPFL, CH-1015 Lausanne, Switzerland.
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Abstract
The development and function of the vertebrate nervous system depend on specific interactions between different cell types. Two examples of such interactions are synaptic transmission and myelination. LGI1-4 (leucine-rich glioma inactivated proteins) play important roles in these processes. They are secreted proteins consisting of an LRR (leucine-rich repeat) domain and a so-called epilepsy-associated or EPTP (epitempin) domain. Both domains are thought to function in protein–protein interactions. The first LGI gene to be identified, LGI1, was found at a chromosomal translocation breakpoint in a glioma cell line. It was subsequently found mutated in ADLTE (autosomal dominant lateral temporal (lobe) epilepsy) also referred to as ADPEAF (autosomal dominant partial epilepsy with auditory features). LGI1 protein appears to act at synapses and antibodies against LGI1 may cause the autoimmune disorder limbic encephalitis. A similar function in synaptic remodelling has been suggested for LGI2, which is mutated in canine Benign Familial Juvenile Epilepsy. LGI4 is required for proliferation of glia in the peripheral nervous system and binds to a neuronal receptor, ADAM22, to foster ensheathment and myelination of axons by Schwann cells. Thus, LGI proteins play crucial roles in nervous system development and function and their study is highly important, both to understand their biological functions and for their therapeutic potential. Here, we review our current knowledge about this important family of proteins, and the progress made towards understanding their functions.
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Mironova YA, Giger RJ. Where no synapses go: gatekeepers of circuit remodeling and synaptic strength. Trends Neurosci 2013; 36:363-73. [PMID: 23642707 DOI: 10.1016/j.tins.2013.04.003] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Revised: 04/01/2013] [Accepted: 04/01/2013] [Indexed: 02/07/2023]
Abstract
Growth inhibitory molecules in the adult mammalian central nervous system (CNS) have been implicated in the blocking of axonal sprouting and regeneration following injury. Prominent CNS regeneration inhibitors include Nogo-A, oligodendrocyte myelin glycoprotein (OMgp), and chondroitin sulfate proteoglycans (CSPGs), and a key question concerns their physiological role in the naïve CNS. Emerging evidence suggests novel functions in dendrites and at synapses of glutamatergic neurons. CNS regeneration inhibitors target the neuronal actin cytoskeleton to regulate dendritic spine maturation, long-term synapse stability, and Hebbian forms of synaptic plasticity. This is accomplished in part by antagonizing plasticity-promoting signaling pathways activated by neurotrophic factors. Altered function of CNS regeneration inhibitors is associated with mental illness and loss of long-lasting memory, suggesting unexpected and novel physiological roles for these molecules in brain health.
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Affiliation(s)
- Yevgeniya A Mironova
- Department of Cell and Developmental Biology, University of Michigan School of Medicine, 3065 BSRB, 109 Zina Pitcher Place, Ann Arbor, MI 48109-2200, USA
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Kempf A, Schwab ME. Nogo-A Represses Anatomical and Synaptic Plasticity in the Central Nervous System. Physiology (Bethesda) 2013; 28:151-63. [DOI: 10.1152/physiol.00052.2012] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Nogo-A was initially discovered as a myelin-associated growth inhibitory protein limiting axonal regeneration after central nervous system (CNS) injury. This review summarizes current knowledge on how myelin and neuronal Nogo-A and its receptors exert physiological functions ranging from the regulation of growth suppression to synaptic plasticity in the developing and adult intact CNS.
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Affiliation(s)
- Anissa Kempf
- Brain Research Institute, University of Zurich, and Department of Health Sciences and Technology, Swiss Federal Institute of Technology (ETH) Zurich, Zurich, Switzerland
| | - Martin E. Schwab
- Brain Research Institute, University of Zurich, and Department of Health Sciences and Technology, Swiss Federal Institute of Technology (ETH) Zurich, Zurich, Switzerland
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48
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Akbik FV, Bhagat SM, Patel PR, Cafferty WBJ, Strittmatter SM. Anatomical plasticity of adult brain is titrated by Nogo Receptor 1. Neuron 2013; 77:859-66. [PMID: 23473316 DOI: 10.1016/j.neuron.2012.12.027] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/11/2012] [Indexed: 11/29/2022]
Abstract
Experience rearranges anatomical connectivity in the brain, but such plasticity is suppressed in adulthood. We examined the turnover of dendritic spines and axonal varicosities in the somatosensory cortex of mice lacking Nogo Receptor 1 (NgR1). Through adolescence, the anatomy and plasticity of ngr1 null mice are indistinguishable from control, but suppression of turnover after age 26 days fails to occur in ngr1-/- mice. Adolescent anatomical plasticity can be restored to 1-year-old mice by conditional deletion of ngr1. Suppression of anatomical dynamics by NgR1 is cell autonomous and is phenocopied by deletion of Nogo-A ligand. Whisker removal deprives the somatosensory cortex of experience-dependent input and reduces dendritic spine turnover in adult ngr1-/- mice to control levels, while an acutely enriched environment increases dendritic spine dynamics in control mice to the level of ngr1-/- mice in a standard environment. Thus, NgR1 determines the low set point for synaptic turnover in adult cerebral cortex.
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Affiliation(s)
- Feras V Akbik
- Cellular Neuroscience, Neurodegeneration and Repair Program, Departments of Neurology and Neurobiology, Yale University School of Medicine, New Haven, CT 06536, USA
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VanGuilder Starkey HD, Bixler GV, Sonntag WE, Freeman WM. Expression of NgR1-antagonizing proteins decreases with aging and cognitive decline in rat hippocampus. Cell Mol Neurobiol 2013; 33:483-8. [PMID: 23525710 DOI: 10.1007/s10571-013-9929-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Accepted: 03/14/2013] [Indexed: 01/26/2023]
Abstract
The myelin-associated inhibitor/Nogo-66 receptor 1 (NgR1) pathway directly functions in negative modulation of structural and electrophysiological synaptic plasticity. A previous study has established an important role of NgR1 pathway signaling in cognitive function, and we have demonstrated that multiple components of this pathway, including ligands, NgR1 co-receptors, and RhoA, are upregulated at the protein level specifically in cognitively impaired, but not age-matched cognitively intact aged rats. Recent studies have identified two novel endogenous NgR1 antagonists, LOTUS and LGI1, and an alternative co-receptor, ADAM22, which act to suppress NgR1 pathway signaling. To determine whether these endogenous NgR1-inhibiting proteins may play a compensatory role in age-related cognitive impairment by counteracting overexpression of NgR1 agonists and co-receptors, we quantified the expression of LOTUS, LGI1, and ADAM22 in hippocampal CA1, CA3 and DG subregions dissected from mature adult and aged rats cognitively phenotyped for spatial learning and memory by Morris water maze testing. We have found that endogenous inhibitors of NgR1 pathway action decrease significantly with aging and cognitive decline and that lower expression levels correlate with declining cognitive ability, particularly in CA1 and CA3. These data suggest that decreased expression of NgR1-antagonizing proteins may exert a combinatorial effect with increased NgR1 signaling pathway components to result in abnormally strong suppression of synaptic plasticity in age-related cognitive impairment.
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Affiliation(s)
- Heather D VanGuilder Starkey
- Department of Pharmacology, Penn State University College of Medicine, 500 University Drive, R130, Hershey, PA 17033, USA
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Abstract
Over the past decade, there has been substantial interest in the role of the integral myelin protein, Nogo-A, from fundamental neurobiological to clinical perspectives. It is now a well-known inhibitor of neurite outgrowth through its cognate receptor, Nogo receptor 1 (NgR1). Nogo-A can only signal through NgR1 upon heteromeric collaboration with p75(NTR), TROY, and LINGO-1 to induce axonal retraction. Both Nogo-A and NgR1 are expressed in multiple sclerosis (MS) lesions, suggesting that Nogo signaling may play a pivotal role in disease progression. There are several approaches targeting Nogo signaling in animal models of MS, and these therapeutic effects are currently in debate. One of the points of contention arises from the localization of the aforementioned signaling molecules, considering that MS and its animal models of disease are governed by inflammatory infiltration of the central nervous system. Furthermore, an impressive list of ligands for NgR1 continues to be compiled, possibly leading to disparities in the results obtained from the various animal models. In this review, we systematically dissect the complexities of Nogo signaling, which may be relevant in the future directions of neuroprotective therapies for MS.
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Affiliation(s)
- Jae Young Lee
- Monash Immunology and Stem Cell Laboratories, Monash University, Clayton, Victoria, Australia
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