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Rybiczka-Tešulov M, Garritsen O, Venø MT, Wieg L, Dijk RV, Rahimi K, Gomes-Duarte A, Wit MD, van de Haar LL, Michels L, van Kronenburg NCH, van der Meer C, Kjems J, Vangoor VR, Pasterkamp RJ. Circular RNAs regulate neuron size and migration of midbrain dopamine neurons during development. Nat Commun 2024; 15:6773. [PMID: 39117691 PMCID: PMC11310423 DOI: 10.1038/s41467-024-51041-1] [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: 05/04/2023] [Accepted: 07/26/2024] [Indexed: 08/10/2024] Open
Abstract
Midbrain dopamine (mDA) neurons play an essential role in cognitive and motor behaviours and are linked to different brain disorders. However, the molecular mechanisms underlying their development, and in particular the role of non-coding RNAs (ncRNAs), remain incompletely understood. Here, we establish the transcriptomic landscape and alternative splicing patterns of circular RNAs (circRNAs) at key developmental timepoints in mouse mDA neurons in vivo using fluorescence-activated cell sorting followed by short- and long-read RNA sequencing. In situ hybridisation shows expression of several circRNAs during early mDA neuron development and post-transcriptional silencing unveils roles for different circRNAs in regulating mDA neuron morphology. Finally, in utero electroporation and time-lapse imaging implicate circRmst, a circRNA with widespread morphological effects, in the migration of developing mDA neurons in vivo. Together, these data for the first time suggest a functional role for circRNAs in developing mDA neurons and characterise poorly defined aspects of mDA neuron development.
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Affiliation(s)
- Mateja Rybiczka-Tešulov
- Department of Translational Neuroscience, UMC Utrecht Brain Center Utrecht, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
- Institute of Medical Genetics, Center for Pathobiochemistry and Genetics, Medical University of Vienna, Vienna, Austria
| | - Oxana Garritsen
- Department of Translational Neuroscience, UMC Utrecht Brain Center Utrecht, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Morten T Venø
- Department of Molecular Biology and Genetics, Interdisciplinary Nanoscience Centre, Aarhus University, Aarhus C, Denmark
- Omiics ApS, Aarhus N, Denmark
| | - Laura Wieg
- Department of Translational Neuroscience, UMC Utrecht Brain Center Utrecht, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Roland van Dijk
- Department of Translational Neuroscience, UMC Utrecht Brain Center Utrecht, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
- VectorY Therapeutics, Matrix Innovation Center VI, Amsterdam, The Netherlands
| | - Karim Rahimi
- Department of Molecular Biology and Genetics, Interdisciplinary Nanoscience Centre, Aarhus University, Aarhus C, Denmark
- Department of Genetics, Blavatnik Institute, Harvard Medical School, MA, Boston, USA
| | - Andreia Gomes-Duarte
- Department of Translational Neuroscience, UMC Utrecht Brain Center Utrecht, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
- VectorY Therapeutics, Matrix Innovation Center VI, Amsterdam, The Netherlands
| | - Marina de Wit
- Department of Translational Neuroscience, UMC Utrecht Brain Center Utrecht, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Lieke L van de Haar
- Department of Translational Neuroscience, UMC Utrecht Brain Center Utrecht, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
- Berlin Institute for Medical Systems Biology, Max Delbrück Center, Berlin, Germany
| | - Lars Michels
- Department of Translational Neuroscience, UMC Utrecht Brain Center Utrecht, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
- VectorY Therapeutics, Matrix Innovation Center VI, Amsterdam, The Netherlands
| | - Nicky C H van Kronenburg
- Department of Translational Neuroscience, UMC Utrecht Brain Center Utrecht, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Christiaan van der Meer
- Department of Translational Neuroscience, UMC Utrecht Brain Center Utrecht, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Jørgen Kjems
- Department of Molecular Biology and Genetics, Interdisciplinary Nanoscience Centre, Aarhus University, Aarhus C, Denmark
| | - Vamshidhar R Vangoor
- Department of Translational Neuroscience, UMC Utrecht Brain Center Utrecht, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - R Jeroen Pasterkamp
- Department of Translational Neuroscience, UMC Utrecht Brain Center Utrecht, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands.
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Thai J, Fuller‐Jackson J, Ivanusic JJ. Using tissue clearing and light sheet fluorescence microscopy for the three-dimensional analysis of sensory and sympathetic nerve endings that innervate bone and dental tissue of mice. J Comp Neurol 2024; 532:e25582. [PMID: 38289188 PMCID: PMC10952626 DOI: 10.1002/cne.25582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 12/05/2023] [Accepted: 12/30/2023] [Indexed: 02/01/2024]
Abstract
Bone and dental tissues are richly innervated by sensory and sympathetic neurons. However, the characterization of the morphology, molecular phenotype, and distribution of nerves that innervate hard tissue has so far mostly been limited to thin histological sections. This approach does not adequately capture dispersed neuronal projections due to the loss of important structural information during three-dimensional (3D) reconstruction. In this study, we modified the immunolabeling-enabled imaging of solvent-cleared organs (iDISCO/iDISCO+) clearing protocol to image high-resolution neuronal structures in whole femurs and mandibles collected from perfused C57Bl/6 mice. Axons and their nerve terminal endings were immunolabeled with antibodies directed against protein gene product 9.5 (pan-neuronal marker), calcitonin gene-related peptide (peptidergic nociceptor marker), or tyrosine hydroxylase (sympathetic neuron marker). Volume imaging was performed using light sheet fluorescence microscopy. We report high-quality immunolabeling of the axons and nerve terminal endings for both sensory and sympathetic neurons that innervate the mouse femur and mandible. Importantly, we are able to follow their projections through full 3D volumes, highlight how extensive their distribution is, and show regional differences in innervation patterns for different parts of each bone (and surrounding tissues). Mapping the distribution of sensory and sympathetic axons, and their nerve terminal endings, in different bony compartments may be important in further elucidating their roles in health and disease.
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Affiliation(s)
- Jenny Thai
- Department of Anatomy and PhysiologyUniversity of MelbourneParkvilleVictoriaAustralia
| | | | - Jason J. Ivanusic
- Department of Anatomy and PhysiologyUniversity of MelbourneParkvilleVictoriaAustralia
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3
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Lin X, Wang W, Yang M, Damseh N, de Sousa MML, Jacob F, Lång A, Kristiansen E, Pannone M, Kissova M, Almaas R, Kuśnierczyk A, Siller R, Shahrour M, Al-Ashhab M, Abu-Libdeh B, Tang W, Slupphaug G, Elpeleg O, Bøe SO, Eide L, Sullivan GJ, Rinholm JE, Song H, Ming GL, van Loon B, Edvardson S, Ye J, Bjørås M. A loss-of-function mutation in human Oxidation Resistance 1 disrupts the spatial-temporal regulation of histone arginine methylation in neurodevelopment. Genome Biol 2023; 24:216. [PMID: 37773136 PMCID: PMC10540402 DOI: 10.1186/s13059-023-03037-1] [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: 05/21/2022] [Accepted: 07/04/2023] [Indexed: 10/01/2023] Open
Abstract
BACKGROUND Oxidation Resistance 1 (OXR1) gene is a highly conserved gene of the TLDc domain-containing family. OXR1 is involved in fundamental biological and cellular processes, including DNA damage response, antioxidant pathways, cell cycle, neuronal protection, and arginine methylation. In 2019, five patients from three families carrying four biallelic loss-of-function variants in OXR1 were reported to be associated with cerebellar atrophy. However, the impact of OXR1 on cellular functions and molecular mechanisms in the human brain is largely unknown. Notably, no human disease models are available to explore the pathological impact of OXR1 deficiency. RESULTS We report a novel loss-of-function mutation in the TLDc domain of the human OXR1 gene, resulting in early-onset epilepsy, developmental delay, cognitive disabilities, and cerebellar atrophy. Patient lymphoblasts show impaired cell survival, proliferation, and hypersensitivity to oxidative stress. These phenotypes are rescued by TLDc domain replacement. We generate patient-derived induced pluripotent stem cells (iPSCs) revealing impaired neural differentiation along with dysregulation of genes essential for neurodevelopment. We identify that OXR1 influences histone arginine methylation by activating protein arginine methyltransferases (PRMTs), suggesting OXR1-dependent mechanisms regulating gene expression during neurodevelopment. We model the function of OXR1 in early human brain development using patient-derived brain organoids revealing that OXR1 contributes to the spatial-temporal regulation of histone arginine methylation in specific brain regions. CONCLUSIONS This study provides new insights into pathological features and molecular underpinnings associated with OXR1 deficiency in patients.
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Affiliation(s)
- Xiaolin Lin
- Department of Microbiology, Oslo University Hospital and University of Oslo, Oslo, Norway
- Department of Biochemistry, Oslo University Hospital and University of Oslo, Oslo, Norway
- Department of Clinical and Molecular Medicine (IKOM), Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway
- Centre for Embryology and Healthy Development, University of Oslo and Oslo University Hospital, 0373, Oslo, Norway
| | - Wei Wang
- Department of Clinical and Molecular Medicine (IKOM), Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway
| | - Mingyi Yang
- Department of Microbiology, Oslo University Hospital and University of Oslo, Oslo, Norway
- Department of Biochemistry, Oslo University Hospital and University of Oslo, Oslo, Norway
- Centre for Embryology and Healthy Development, University of Oslo and Oslo University Hospital, 0373, Oslo, Norway
- Norwegian Centre for Stem Cell Research, Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Nadirah Damseh
- Department of Pediatrics, Makassed Hospital and Al-Quds University, East Jerusalem, Palestine
| | - Mirta Mittelstedt Leal de Sousa
- Department of Clinical and Molecular Medicine (IKOM), Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway
| | - Fadi Jacob
- Department of Neuroscience and Mahoney Institute for Neurosciences, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Anna Lång
- Department of Microbiology, Oslo University Hospital and University of Oslo, Oslo, Norway
- Department of Biochemistry, Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Elise Kristiansen
- Department of Microbiology, Oslo University Hospital and University of Oslo, Oslo, Norway
- Centre for Embryology and Healthy Development, University of Oslo and Oslo University Hospital, 0373, Oslo, Norway
| | - Marco Pannone
- Department of Clinical and Molecular Medicine (IKOM), Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway
| | - Miroslava Kissova
- Department of Clinical and Molecular Medicine (IKOM), Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway
| | - Runar Almaas
- Department of Pediatric Research, Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Anna Kuśnierczyk
- Department of Microbiology, Oslo University Hospital and University of Oslo, Oslo, Norway
- The Proteomics and Metabolomics Core Facility (PROMEC), Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway
| | - Richard Siller
- Norwegian Centre for Stem Cell Research, Oslo University Hospital and University of Oslo, Oslo, Norway
- Department of Molecular Medicine, University of Oslo, Oslo, Norway
| | - Maher Shahrour
- Department of Pediatrics, Makassed Hospital and Al-Quds University, East Jerusalem, Palestine
- Department of Newborn and Developmental Paediatrics, Toronto, ON, Canada
| | - Motee Al-Ashhab
- Department of Pediatrics, Makassed Hospital and Al-Quds University, East Jerusalem, Palestine
| | - Bassam Abu-Libdeh
- Department of Pediatrics, Makassed Hospital and Al-Quds University, East Jerusalem, Palestine
| | - Wannan Tang
- Department of Clinical and Molecular Medicine (IKOM), Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway
| | - Geir Slupphaug
- Department of Microbiology, Oslo University Hospital and University of Oslo, Oslo, Norway
- The Proteomics and Metabolomics Core Facility (PROMEC), Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway
| | - Orly Elpeleg
- Department of Genetics, Hadassah University Hospital, Jerusalem, Israel
| | - Stig Ove Bøe
- Department of Microbiology, Oslo University Hospital and University of Oslo, Oslo, Norway
- Department of Biochemistry, Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Lars Eide
- Department of Biochemistry, Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Gareth J Sullivan
- Norwegian Centre for Stem Cell Research, Oslo University Hospital and University of Oslo, Oslo, Norway
- Department of Molecular Medicine, University of Oslo, Oslo, Norway
- Department of Immunology, Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Johanne Egge Rinholm
- Department of Microbiology, Oslo University Hospital and University of Oslo, Oslo, Norway
- The Proteomics and Metabolomics Core Facility (PROMEC), Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway
| | - Hongjun Song
- Department of Neuroscience and Mahoney Institute for Neurosciences, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Guo-Li Ming
- Department of Neuroscience and Mahoney Institute for Neurosciences, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Barbara van Loon
- Department of Clinical and Molecular Medicine (IKOM), Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway
| | - Simon Edvardson
- Department of Genetics, Hadassah University Hospital, Jerusalem, Israel.
| | - Jing Ye
- Department of Clinical and Molecular Medicine (IKOM), Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway.
| | - Magnar Bjørås
- Department of Microbiology, Oslo University Hospital and University of Oslo, Oslo, Norway.
- Department of Biochemistry, Oslo University Hospital and University of Oslo, Oslo, Norway.
- Department of Clinical and Molecular Medicine (IKOM), Norwegian University of Science and Technology (NTNU), 7491, Trondheim, Norway.
- Centre for Embryology and Healthy Development, University of Oslo and Oslo University Hospital, 0373, Oslo, Norway.
- Norwegian Centre for Stem Cell Research, Oslo University Hospital and University of Oslo, Oslo, Norway.
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Li Y, Zhu M, Chen WX, Luo J, Li X, Cao Y, Zheng M, Ma S, Xiao Z, Zhang Y, Jiang L, Wang X, Tan T, Li X, Gong Q, Xiong X, Wang J, Tang M, Li M, Tang YP. A novel mutation in intron 1 of Wnt1 causes developmental loss of dopaminergic neurons in midbrain and ASD-like behaviors in rats. Mol Psychiatry 2023; 28:3795-3805. [PMID: 37658228 PMCID: PMC10730402 DOI: 10.1038/s41380-023-02223-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 08/02/2023] [Accepted: 08/07/2023] [Indexed: 09/03/2023]
Abstract
Autism spectrum disorder (ASD) is a group of neurodevelopmental disorders with a strong genetic liability. Despite extensive studies, however, the underlying pathogenic mechanism still remains elusive. In the present study, we identified a homozygous mutation in the intron 1 of Wnt1 via large-scale screening of ASD risk/causative genes and verified that this mutation created a new splicing donor site in the intron 1, and consequently, a decrease of WNT1 expression. Interestingly, humanized rat models harboring this mutation exhibited robust ASD-like behaviors including impaired ultrasonic vocalization (USV), decreased social interactions, and restricted and repetitive behaviors. Moreover, in the substantia nigra compacta (SNpc) and the ventral tegmental area (VTA) of mutant rats, dopaminergic (DAergic) neurons were dramatically lost, together with a comparable decrease in striatal DAergic fibers. Furthermore, using single-cell RNA sequencing, we demonstrated that the decreased DAergic neurons in these midbrain areas might attribute to a shift of the boundary of the local pool of progenitor cells from the hypothalamic floor plate to the midbrain floor plate during the early embryonic stage. Moreover, treatments of mutant rats with levodopa could attenuate the impaired USV and social interactions almost completely, but not the restricted and repetitive behaviors. Our results for the first time documented that the developmental loss of DAergic neurons in the midbrain underlies the pathogenesis of ASD, and that the abnormal progenitor cell patterning is a cellular underpinning for this developmental DAergic neuronal loss. Importantly, the effective dopamine therapy suggests a translational significance in the treatment of ASD.
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Affiliation(s)
- Yongyi Li
- Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China
- Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, China
| | - Mingwei Zhu
- Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, China
| | - Wen-Xiong Chen
- Department of Neurology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, China
| | - Jing Luo
- School of Basic Medicine, Southwest Medical University, Luzhou, Sichuan, 646000, China
| | - Xin Li
- Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, China
- School of Basic Medicine, Southwest Medical University, Luzhou, Sichuan, 646000, China
- Department of Pathology, Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan, 646000, China
| | - Yangyang Cao
- Department of Child Health, Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, 450052, China
| | - Meng Zheng
- Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, China
| | - Shanshan Ma
- Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China
| | - Zhilan Xiao
- Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, China
| | - Yani Zhang
- Department of Neurology, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, China
| | - Linyan Jiang
- Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, China
| | - Xiumin Wang
- Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, China
| | - Ting Tan
- Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, China
| | - Xia Li
- Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, China
| | - Qian Gong
- Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, China
| | - Xiaoli Xiong
- Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, China
| | - Jun Wang
- Department of Child Health, Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, 450052, China
| | - Mingxi Tang
- Department of Pathology, Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan, 646000, China.
| | - Mingtao Li
- Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China.
- Department of Pharmacology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China.
| | - Ya-Ping Tang
- Guangdong Provincial Key Laboratory of Brain Function and Disease, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, 510080, China.
- Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, 510623, China.
- Department of Child Health, Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, 450052, China.
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5
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Gamit N, Dharmarajan A, Sethi G, Warrier S. Want of Wnt in Parkinson's disease: Could sFRP disrupt interplay between Nurr1 and Wnt signaling? Biochem Pharmacol 2023; 212:115566. [PMID: 37088155 DOI: 10.1016/j.bcp.2023.115566] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 04/14/2023] [Accepted: 04/17/2023] [Indexed: 04/25/2023]
Abstract
Nuclear receptor related 1 (Nurr1) is a transcription factor known to regulate the development and maintenance of midbrain dopaminergic (mDA) neurons. Reports have confirmed that defect or obliteration of Nurr1 results in neurodegeneration and motor function impairment leading to Parkinson's disease (PD). Studies have also indicated that Nurr1 regulates the expression of alpha-synuclein (α-SYN) and mutations in Nurr1 cause α-SYN overexpression, thereby increasing the risk of PD. Nurr1 is modulated via various pathways including Wnt signaling pathway which is known to play an important role in neurogenesis and deregulation of it contributes to PD pathogenesis. Both Wnt/β-catenin dependent and independent pathways are implicated in the activation of Nurr1 and subsequent downregulation of α-SYN. This review highlights the interaction between Nurr1 and Wnt signaling pathways in mDA neuronal development. We further hypothesize how modulation of Wnt signaling pathway by its antagonist, secreted frizzled related proteins (sFRPs) could be a potential route to treat PD.
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Affiliation(s)
- Naisarg Gamit
- Division of Cancer Stem Cells and Cardiovascular Regeneration, Manipal Institute of Regenerative Medicine, Manipal Academy of Higher Education (MAHE), Bangalore 560 065, India
| | - Arun Dharmarajan
- Department of Biomedical Sciences, Faculty of Biomedical Sciences, Technology and Research, Sri Ramachandra Institute of Higher Education and Research, Chennai 600 116, India; School of Pharmacy and Biomedical Sciences, Curtin Medical School, Curtin University, Perth, Western Australia 6102, Australia; Curtin Health and Innovation Research Institute, Curtin University, Perth, Western Australia 6102, Australia; School of Human Sciences, Faculty of Life and Physical Sciences, The University of Western Australia, Perth, Western Australia 6009, Australia
| | - Gautam Sethi
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore 117 600, Singapore
| | - Sudha Warrier
- Division of Cancer Stem Cells and Cardiovascular Regeneration, Manipal Institute of Regenerative Medicine, Manipal Academy of Higher Education (MAHE), Bangalore 560 065, India; Cuor Stem Cellutions Pvt Ltd, Manipal Institute of Regenerative Medicine, Manipal Academy of Higher Education (MAHE), Bangalore 560 065, India.
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6
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Abstract
The midbrain dopamine (mDA) system is composed of molecularly and functionally distinct neuron subtypes that mediate specific behaviours and are linked to various brain diseases. Considerable progress has been made in identifying mDA neuron subtypes, and recent work has begun to unveil how these neuronal subtypes develop and organize into functional brain structures. This progress is important for further understanding the disparate physiological functions of mDA neurons and their selective vulnerability in disease, and will ultimately accelerate therapy development. This Review discusses recent advances in our understanding of molecularly defined mDA neuron subtypes and their circuits, ranging from early developmental events, such as neuron migration and axon guidance, to their wiring and function, and future implications for therapeutic strategies.
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7
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Li H, Jiang H, Li H, Li L, Yan Z, Feng J. Generation of human A9 dopaminergic pacemakers from induced pluripotent stem cells. Mol Psychiatry 2022; 27:4407-4418. [PMID: 35610351 PMCID: PMC9684358 DOI: 10.1038/s41380-022-01628-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 05/04/2022] [Accepted: 05/12/2022] [Indexed: 12/14/2022]
Abstract
The degeneration of nigral (A9) dopaminergic (DA) neurons causes motor symptoms in Parkinson's disease (PD). We use small-molecule compounds to direct the differentiation of human induced pluripotent stem cells (iPSCs) to A9 DA neurons that share many important properties with their in vivo counterparts. The method generates a large percentage of TH+ neurons that express appropriate A9 markers, such as GIRK2 and ALDH1A1, but mostly not the A10 marker CALBINDIN. Functionally, they exhibit autonomous pacemaking based on L-type voltage-dependent Ca2+ channels and show autoreceptor-dependent regulation of dopamine release. When transplanted in the striatum of 6-OHDA-lesioned athymic rats, the human A9 DA neurons manifest robust survival and axon outgrowth, and ameliorate motor deficits in the rat PD model. The ability to generate patient-specific A9 DA autonomous pacemakers will significantly improve PD research and facilitate the development of disease-modifying therapies.
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Affiliation(s)
- Hong Li
- Department of Physiology and Biophysics, State University of New York at Buffalo, Buffalo, NY, 14203, USA
| | - Houbo Jiang
- Department of Physiology and Biophysics, State University of New York at Buffalo, Buffalo, NY, 14203, USA
- Veterans Affairs Western New York Healthcare System, Buffalo, NY, 14215, USA
| | - Hanqin Li
- Department of Physiology and Biophysics, State University of New York at Buffalo, Buffalo, NY, 14203, USA
| | - Li Li
- Department of Physiology and Biophysics, State University of New York at Buffalo, Buffalo, NY, 14203, USA
| | - Zhen Yan
- Department of Physiology and Biophysics, State University of New York at Buffalo, Buffalo, NY, 14203, USA
- Veterans Affairs Western New York Healthcare System, Buffalo, NY, 14215, USA
| | - Jian Feng
- Department of Physiology and Biophysics, State University of New York at Buffalo, Buffalo, NY, 14203, USA.
- Veterans Affairs Western New York Healthcare System, Buffalo, NY, 14215, USA.
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8
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Earley AM, Burbulla LF, Krainc D, Awatramani R. Identification of ASCL1 as a determinant for human iPSC-derived dopaminergic neurons. Sci Rep 2021; 11:22257. [PMID: 34782629 PMCID: PMC8593045 DOI: 10.1038/s41598-021-01366-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Accepted: 10/26/2021] [Indexed: 12/24/2022] Open
Abstract
During cellular specification, transcription factors orchestrate cellular decisions through gene regulation. By hijacking these transcriptional networks, human pluripotent stem cells (hPSCs) can be specialized into neurons with different molecular identities for the purposes of regenerative medicine and disease modeling. However, molecular fine tuning cell types to match their in vivo counterparts remains a challenge. Directing cell fates often result in blended or incomplete neuron identities. A better understanding of hPSC to neuron gene regulation is needed. Here, we used single cell RNA sequencing to resolve some of these graded molecular identities during human neurogenesis from hPSCs. Differentiation platforms were established to model neural induction from stem cells, and we characterized these differentiated cell types by 10x single cell RNA sequencing. Using single cell trajectory and co-expression analyses, we identified a co-regulated transcription factor module expressing achaete-scute family basic helix-loop-helix transcription factor 1 (ASCL1) and neuronal differentiation 1 (NEUROD1). We then tested the function of these transcription factors in neuron subtype differentiation by gene knockout in a novel human system that reports the expression of tyrosine hydroxylase (TH), the rate limiting enzyme in dopamine synthesis. ASCL1 was identified as a necessary transcription factor for regulating dopaminergic neurotransmitter selection.
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Affiliation(s)
- Aaron M Earley
- Ken & Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA
| | - Lena F Burbulla
- Ken & Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA
- German Center for Neurodegenerative Diseases (DZNE), Munich, Germany
- Metabolic Biochemistry, Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians University, Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Dimitri Krainc
- Ken & Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA
| | - Rajeshwar Awatramani
- Ken & Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, 60611, USA.
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9
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Pereira Luppi M, Azcorra M, Caronia-Brown G, Poulin JF, Gaertner Z, Gatica S, Moreno-Ramos OA, Nouri N, Dubois M, Ma YC, Ramakrishnan C, Fenno L, Kim YS, Deisseroth K, Cicchetti F, Dombeck DA, Awatramani R. Sox6 expression distinguishes dorsally and ventrally biased dopamine neurons in the substantia nigra with distinctive properties and embryonic origins. Cell Rep 2021; 37:109975. [PMID: 34758317 PMCID: PMC8607753 DOI: 10.1016/j.celrep.2021.109975] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 09/15/2021] [Accepted: 10/19/2021] [Indexed: 12/12/2022] Open
Abstract
Dopamine (DA) neurons in the ventral tier of the substantia nigra pars compacta (SNc) degenerate prominently in Parkinson's disease, while those in the dorsal tier are relatively spared. Defining the molecular, functional, and developmental characteristics of each SNc tier is crucial to understand their distinct susceptibility. We demonstrate that Sox6 expression distinguishes ventrally and dorsally biased DA neuron populations in the SNc. The Sox6+ population in the ventral SNc includes an Aldh1a1+ subset and is enriched in gene pathways that underpin vulnerability. Sox6+ neurons project to the dorsal striatum and show activity correlated with acceleration. Sox6- neurons project to the medial, ventral, and caudal striatum and respond to rewards. Moreover, we show that this adult division is encoded early in development. Overall, our work demonstrates a dual origin of the SNc that results in DA neuron cohorts with distinct molecular profiles, projections, and functions.
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Affiliation(s)
- Milagros Pereira Luppi
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Maite Azcorra
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA; Department of Neurobiology, Northwestern University, Evanston, IL, USA
| | - Giuliana Caronia-Brown
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Jean-Francois Poulin
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA; Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Zachary Gaertner
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Serafin Gatica
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | | | - Navid Nouri
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Marilyn Dubois
- Department of Psychiatry and Neuroscience, Faculty of Medicine, Université Laval, Québec, QC, Canada
| | - Yongchao C Ma
- Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Charu Ramakrishnan
- Department of Bioengineering, Stanford University School of Medicine, Stanford, CA, USA
| | - Lief Fenno
- Department of Bioengineering, Stanford University School of Medicine, Stanford, CA, USA
| | - Yoon Seok Kim
- Department of Bioengineering, Stanford University School of Medicine, Stanford, CA, USA
| | - Karl Deisseroth
- Department of Bioengineering, Stanford University School of Medicine, Stanford, CA, USA
| | - Francesca Cicchetti
- Department of Psychiatry and Neuroscience, Faculty of Medicine, Université Laval, Québec, QC, Canada
| | - Daniel A Dombeck
- Department of Neurobiology, Northwestern University, Evanston, IL, USA.
| | - Rajeshwar Awatramani
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
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10
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Nouri P, Götz S, Rauser B, Irmler M, Peng C, Trümbach D, Kempny C, Lechermeier CG, Bryniok A, Dlugos A, Euchner E, Beckers J, Brodski C, Klümper C, Wurst W, Prakash N. Dose-Dependent and Subset-Specific Regulation of Midbrain Dopaminergic Neuron Differentiation by LEF1-Mediated WNT1/b-Catenin Signaling. Front Cell Dev Biol 2020; 8:587778. [PMID: 33195246 PMCID: PMC7649324 DOI: 10.3389/fcell.2020.587778] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 09/01/2020] [Indexed: 01/07/2023] Open
Abstract
The mesodiencephalic dopaminergic (mdDA) neurons, including the nigrostriatal subset that preferentially degenerates in Parkinson’s Disease (PD), strongly depend on an accurately balanced Wingless-type MMTV integration site family member 1 (WNT1)/beta-catenin signaling pathway during their development. Loss of this pathway abolishes the generation of these neurons, whereas excessive WNT1/b-catenin signaling prevents their correct differentiation. The identity of the cells responding to this pathway in the developing mammalian ventral midbrain (VM) as well as the precise progression of WNT/b-catenin action in these cells are still unknown. We show that strong WNT/b-catenin signaling inhibits the differentiation of WNT/b-catenin-responding mdDA progenitors into PITX3+ and TH+ mdDA neurons by repressing the Pitx3 gene in mice. This effect is mediated by RSPO2, a WNT/b-catenin agonist, and lymphoid enhancer binding factor 1 (LEF1), an essential nuclear effector of the WNT/b-catenin pathway, via conserved LEF1/T-cell factor binding sites in the Pitx3 promoter. LEF1 expression is restricted to a caudolateral mdDA progenitor subset that preferentially responds to WNT/b-catenin signaling and gives rise to a fraction of all mdDA neurons. Our data indicate that an attenuation of WNT/b-catenin signaling in mdDA progenitors is essential for their correct differentiation into specific mdDA neuron subsets. This is an important consideration for stem cell-based regenerative therapies and in vitro models of neuropsychiatric diseases.
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Affiliation(s)
- Parivash Nouri
- Laboratory of Applied Genetics and Stem Cell Biology, Department Hamm 2, Hamm-Lippstadt University of Applied Sciences, Hamm, Germany
| | - Sebastian Götz
- Institute of Developmental Genetics, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany
| | - Benedict Rauser
- Institute of Developmental Genetics, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany
| | - Martin Irmler
- Institute of Experimental Genetics, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany
| | - Changgeng Peng
- Institute of Developmental Genetics, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany.,Advanced Institute of Translational Medicine, The First Rehabilitation Hospital of Shanghai, Tongji University School of Medicine, Tongji University, Shanghai, China
| | - Dietrich Trümbach
- Institute of Developmental Genetics, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany
| | - Christian Kempny
- Laboratory of Applied Genetics and Stem Cell Biology, Department Hamm 2, Hamm-Lippstadt University of Applied Sciences, Hamm, Germany
| | - Carina G Lechermeier
- Institute of Developmental Genetics, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany
| | - Agnes Bryniok
- Laboratory of Applied Genetics and Stem Cell Biology, Department Hamm 2, Hamm-Lippstadt University of Applied Sciences, Hamm, Germany
| | - Andrea Dlugos
- Laboratory of Applied Genetics and Stem Cell Biology, Department Hamm 2, Hamm-Lippstadt University of Applied Sciences, Hamm, Germany
| | - Ellen Euchner
- Laboratory of Applied Genetics and Stem Cell Biology, Department Hamm 2, Hamm-Lippstadt University of Applied Sciences, Hamm, Germany
| | - Johannes Beckers
- Institute of Experimental Genetics, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany.,Chair of Experimental Genetics, Technical University of Munich, Munich, Germany.,German Center for Diabetes Research, Neuherberg, Germany
| | - Claude Brodski
- Department of Physiology and Cell Biology, Zlotowski Center for Neuroscience, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beersheba, Israel
| | - Claudia Klümper
- Laboratory of Applied Genetics and Stem Cell Biology, Department Hamm 2, Hamm-Lippstadt University of Applied Sciences, Hamm, Germany
| | - Wolfgang Wurst
- Institute of Developmental Genetics, Helmholtz Zentrum München - German Research Center for Environmental Health, Neuherberg, Germany.,Chair of Developmental Genetics, Helmholtz Zentrum München, Technical University of Munich/Helmholtz Zentrum München, Neuherberg, Germany.,German Center for Neurodegenerative Diseases, Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Nilima Prakash
- Laboratory of Applied Genetics and Stem Cell Biology, Department Hamm 2, Hamm-Lippstadt University of Applied Sciences, Hamm, Germany
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11
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Colucci-D’Amato L, Speranza L, Volpicelli F. Neurotrophic Factor BDNF, Physiological Functions and Therapeutic Potential in Depression, Neurodegeneration and Brain Cancer. Int J Mol Sci 2020; 21:E7777. [PMID: 33096634 PMCID: PMC7589016 DOI: 10.3390/ijms21207777] [Citation(s) in RCA: 382] [Impact Index Per Article: 95.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 10/16/2020] [Accepted: 10/19/2020] [Indexed: 01/10/2023] Open
Abstract
Brain-derived neurotrophic factor (BDNF) is one of the most distributed and extensively studied neurotrophins in the mammalian brain. BDNF signals through the tropomycin receptor kinase B (TrkB) and the low affinity p75 neurotrophin receptor (p75NTR). BDNF plays an important role in proper growth, development, and plasticity of glutamatergic and GABAergic synapses and through modulation of neuronal differentiation, it influences serotonergic and dopaminergic neurotransmission. BDNF acts as paracrine and autocrine factor, on both pre-synaptic and post-synaptic target sites. It is crucial in the transformation of synaptic activity into long-term synaptic memories. BDNF is considered an instructive mediator of functional and structural plasticity in the central nervous system (CNS), influencing dendritic spines and, at least in the hippocampus, the adult neurogenesis. Changes in the rate of adult neurogenesis and in spine density can influence several forms of learning and memory and can contribute to depression-like behaviors. The possible roles of BDNF in neuronal plasticity highlighted in this review focus on the effect of antidepressant therapies on BDNF-mediated plasticity. Moreover, we will review data that illustrate the role of BDNF as a potent protective factor that is able to confer protection against neurodegeneration, in particular in Alzheimer's disease. Finally, we will give evidence of how the involvement of BDNF in the pathogenesis of brain glioblastoma has emerged, thus opening new avenues for the treatment of this deadly cancer.
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Affiliation(s)
- Luca Colucci-D’Amato
- Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, University of Campania “Luigi Vanvitelli”, 81100 Caserta, Italy
- InterUniversity Center for Research in Neurosciences (CIRN), University of Campania "Luigi Vanvitelli", 80131 Naples, Italy
| | - Luisa Speranza
- Department of Neuroscience, Albert Einstein College of Medicine, New York, NY 10461, USA;
| | - Floriana Volpicelli
- Department of Pharmacy, School of Medicine and Surgery, University of Naples Federico II, 80131 Naples, Italy;
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12
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Ásgrímsdóttir ES, Arenas E. Midbrain Dopaminergic Neuron Development at the Single Cell Level: In vivo and in Stem Cells. Front Cell Dev Biol 2020; 8:463. [PMID: 32733875 PMCID: PMC7357704 DOI: 10.3389/fcell.2020.00463] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 05/19/2020] [Indexed: 12/13/2022] Open
Abstract
Parkinson's disease (PD) is a progressive neurodegenerative disorder that predominantly affects dopaminergic (DA) neurons of the substantia nigra. Current treatment options for PD are symptomatic and typically involve the replacement of DA neurotransmission by DA drugs, which relieve the patients of some of their motor symptoms. However, by the time of diagnosis, patients have already lost about 70% of their substantia nigra DA neurons and these drugs offer only temporary relief. Therefore, cell replacement therapy has garnered much interest as a potential treatment option for PD. Early studies using human fetal tissue for transplantation in PD patients provided proof of principle for cell replacement therapy, but they also highlighted the ethical and practical difficulties associated with using human fetal tissue as a cell source. In recent years, advancements in stem cell research have made human pluripotent stem cells (hPSCs) an attractive source of material for cell replacement therapy. Studies on how DA neurons are specified and differentiated in the developing mouse midbrain have allowed us to recapitulate many of the positional and temporal cues needed to generate DA neurons in vitro. However, little is known about the developmental programs that govern human DA neuron development. With the advent of single-cell RNA sequencing (scRNA-seq) and bioinformatics, it has become possible to analyze precious human samples with unprecedented detail and extract valuable high-quality information from large data sets. This technology has allowed the systematic classification of cell types present in the human developing midbrain along with their gene expression patterns. By studying human development in such an unbiased manner, we can begin to elucidate human DA neuron development and determine how much it differs from our knowledge of the rodent brain. Importantly, this molecular description of the function of human cells has become and will increasingly be a reference to define, evaluate, and engineer cell types for PD cell replacement therapy and disease modeling.
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Affiliation(s)
| | - Ernest Arenas
- Division of Molecular Neurobiology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
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13
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Molecular Regulation in Dopaminergic Neuron Development. Cues to Unveil Molecular Pathogenesis and Pharmacological Targets of Neurodegeneration. Int J Mol Sci 2020; 21:ijms21113995. [PMID: 32503161 PMCID: PMC7312927 DOI: 10.3390/ijms21113995] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 05/30/2020] [Accepted: 06/01/2020] [Indexed: 12/13/2022] Open
Abstract
The relatively few dopaminergic neurons in the mammalian brain are mostly located in the midbrain and regulate many important neural functions, including motor integration, cognition, emotive behaviors and reward. Therefore, alteration of their function or degeneration leads to severe neurological and neuropsychiatric diseases. Unraveling the mechanisms of midbrain dopaminergic (mDA) phenotype induction and maturation and elucidating the role of the gene network involved in the development and maintenance of these neurons is of pivotal importance to rescue or substitute these cells in order to restore dopaminergic functions. Recently, in addition to morphogens and transcription factors, microRNAs have been identified as critical players to confer mDA identity. The elucidation of the gene network involved in mDA neuron development and function will be crucial to identify early changes of mDA neurons that occur in pre-symptomatic pathological conditions, such as Parkinson’s disease. In addition, it can help to identify targets for new therapies and for cell reprogramming into mDA neurons. In this essay, we review the cascade of transcriptional and posttranscriptional regulation that confers mDA identity and regulates their functions. Additionally, we highlight certain mechanisms that offer important clues to unveil molecular pathogenesis of mDA neuron dysfunction and potential pharmacological targets for the treatment of mDA neuron dysfunction.
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14
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Poulin JF, Gaertner Z, Moreno-Ramos OA, Awatramani R. Classification of Midbrain Dopamine Neurons Using Single-Cell Gene Expression Profiling Approaches. Trends Neurosci 2020; 43:155-169. [PMID: 32101709 PMCID: PMC7285906 DOI: 10.1016/j.tins.2020.01.004] [Citation(s) in RCA: 126] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 12/13/2019] [Accepted: 01/11/2020] [Indexed: 01/31/2023]
Abstract
Dysfunctional dopamine (DA) signaling has been associated with a broad spectrum of neuropsychiatric disorders, prompting investigations into how midbrain DA neuron heterogeneity may underpin this variety of behavioral symptoms. Emerging literature indeed points to functional heterogeneity even within anatomically defined DA clusters. Recognizing the need for a systematic classification scheme, several groups have used single-cell profiling to catalog DA neurons based on their gene expression profiles. We aim here not only to synthesize points of congruence but also to highlight key differences between the molecular classification schemes derived from these studies. In doing so, we hope to provide a common framework that will facilitate investigations into the functions of DA neuron subtypes in the healthy and diseased brain.
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Affiliation(s)
- Jean-Francois Poulin
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Zachary Gaertner
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | | | - Rajeshwar Awatramani
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
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15
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Thai J, Kyloh M, Travis L, Spencer NJ, Ivanusic JJ. Identifying spinal afferent (sensory) nerve endings that innervate the marrow cavity and periosteum using anterograde tracing. J Comp Neurol 2020; 528:1903-1916. [PMID: 31970770 DOI: 10.1002/cne.24862] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 01/16/2020] [Accepted: 01/16/2020] [Indexed: 01/04/2023]
Abstract
While sensory and sympathetic neurons are known to innervate bone, previous studies have found it difficult to unequivocally identify and characterize only those that are of sensory origin. In this study, we have utilized an in vivo anterograde tracing technique to selectively label spinal afferent (sensory) nerve endings that innervate the periosteum and marrow cavity of murine long bones. Unilateral injections of dextran-biotin (anterograde tracer; 20% in saline, 50-100 nl) were made into L3-L5 dorsal root ganglia. After a 10-day recovery period to allow sufficient time for selective anterograde transport of the tracer to nerve terminal endings in bone, the periosteum (whole-mount) and underlying bone were collected, processed to reveal anterograde labeling, and immuno-labeled with antibodies directed against protein gene product (pan-neuronal marker; PGP9.5), tyrosine hydroxylase (sympathetic neuron marker; TH), calcitonin gene-related protein (peptidergic nociceptor marker; CGRP), and/or neurofilament 200 (myelinated axon marker; NF200). Anterograde-labeled nerve endings were dispersed throughout the periosteum and marrow cavity and could be identified in close apposition to blood vessels and at sites distant from them. The periosteum and the marrow cavity were each innervated by myelinated (NF200+) sensory neurons, and unmyelinated (NF200-) sensory neurons that were either peptidergic (CGRP+) or nonpeptidergic (CGRP-). Spinal afferent nerve endings did not express TH, and lacked the cylindrical morphology around blood vessels characteristic of sympathetic innervation. This approach to selective labeling of sensory nerve terminal endings will help to better identify how different sub-populations of sensory neurons, and their peripheral nerve terminal endings, interact with bone.
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Affiliation(s)
- Jenny Thai
- Department of Anatomy and Neuroscience, University of Melbourne, Parkville, Victoria, Australia
| | - Melinda Kyloh
- College of Medicine and Public Health and Centre for Neuroscience, Flinders University, Adelaide, South Australia, Australia
| | - Lee Travis
- College of Medicine and Public Health and Centre for Neuroscience, Flinders University, Adelaide, South Australia, Australia
| | - Nick J Spencer
- College of Medicine and Public Health and Centre for Neuroscience, Flinders University, Adelaide, South Australia, Australia
| | - Jason J Ivanusic
- Department of Anatomy and Neuroscience, University of Melbourne, Parkville, Victoria, Australia
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16
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A population of nonneuronal GFRα3-expressing cells in the bone marrow resembles nonmyelinating Schwann cells. Cell Tissue Res 2019; 378:441-456. [DOI: 10.1007/s00441-019-03068-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 07/01/2019] [Indexed: 12/17/2022]
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17
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Brown S, Zervas M. Temporal Expression of Wnt1 Defines the Competency State and Terminal Identity of Progenitors in the Developing Cochlear Nucleus and Inferior Colliculus. Front Neuroanat 2017; 11:67. [PMID: 28878630 PMCID: PMC5572273 DOI: 10.3389/fnana.2017.00067] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2017] [Accepted: 07/19/2017] [Indexed: 11/25/2022] Open
Abstract
The auditory system contains a diverse array of interconnected anatomical structures that mediate the perception of sound. The cochlear nucleus of the hindbrain serves as the initial site of convergence for auditory stimuli, while the inferior colliculus of the midbrain serves as an integration and relay station for all ascending auditory information. We used Genetic Inducible Fate Mapping (GIFM) to determine how the timing of Wnt1 expression is related to the competency states of auditory neuron progenitors. We demonstrate that the Wnt1 lineage defines progenitor pools of auditory neurons in the developing midbrain and hindbrain. The timing of Wnt1 expression specifies unique cell types during embryogenesis and follows a mixed model encompassing a brief epoch of de novo expression followed by rapid and progressive lineage restriction to shape the inferior colliculus. In contrast, Wnt1 fate mapping of the embryonic hindbrain revealed de novo induction of Wnt1 in auditory hindbrain progenitors, which is related to the development of biochemically distinct neurons in the cochlear nucleus. Thus, we uncovered two modes of lineage allocation that explain the relationship between the timing of Wnt1 expression and the development of the cochlear nucleus and the inferior colliculus. Finally, our analysis of Wnt1sw/sw mutant mice demonstrated a functional requirement of Wnt1 for the development of auditory midbrain and hindbrain neurons. Collectively, our study provides a deeper understanding of Wnt1 lineage allocation and function in mammalian brain development.
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Affiliation(s)
- Stephen Brown
- Department of Molecular Biology, Cell Biology and Biochemistry, Division of Biology and Medicine, Brown University, ProvidenceRI, United States
| | - Mark Zervas
- Department of Molecular Biology, Cell Biology and Biochemistry, Division of Biology and Medicine, Brown University, ProvidenceRI, United States.,Department of Neuroscience, Division of Biology and Medicine, Brown University, ProvidenceRI, United States.,Department of Neuroscience, Amgen, CambridgeMA, United States
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18
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Studying Mesodiencephalic Dopaminergic Neuron Development In Vivo to Improve Stem Cell Therapy in Parkinson's Disease. J Neurosci 2016; 36:1794-6. [PMID: 26865605 DOI: 10.1523/jneurosci.4285-15.2016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
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19
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Bodea GO, Blaess S. Establishing diversity in the dopaminergic system. FEBS Lett 2015; 589:3773-85. [PMID: 26431946 DOI: 10.1016/j.febslet.2015.09.016] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2015] [Revised: 09/13/2015] [Accepted: 09/16/2015] [Indexed: 11/19/2022]
Abstract
Midbrain dopaminergic neurons (MbDNs) modulate cognitive processes, regulate voluntary movement, and encode reward prediction errors and aversive stimuli. While the degeneration of MbDNs underlies the motor defects in Parkinson's disease, imbalances in dopamine levels are associated with neuropsychiatric disorders such as depression, schizophrenia and substance abuse. In recent years, progress has been made in understanding how MbDNs, which constitute a relatively small neuronal population in the brain, can contribute to such diverse functions and dysfunctions. In particular, important insights have been gained regarding the distinct molecular, neurochemical and network properties of MbDNs. How this diversity of MbDNs is established during brain development is only starting to be unraveled. In this review, we summarize the current knowledge on the diversity in MbDN progenitors and differentiated MbDNs in the developing rodent brain. We discuss the signaling pathways, transcription factors and transmembrane receptors that contribute to setting up these diverse MbDN subpopulations. A better insight into the processes that establish diversity in MbDNs will ultimately improve the understanding of the architecture and function of the dopaminergic system in the adult brain.
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Affiliation(s)
- Gabriela O Bodea
- Mater Research Institute - University of Queensland, Translational Research Institute, Woolloongabba, QLD 4102, Australia; Queensland Brain Institute, University of Queensland, Brisbane, QLD 4072, Australia
| | - Sandra Blaess
- Institute of Reconstructive Neurobiology, Life and Brain Center, University of Bonn, Bonn, Germany.
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20
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Abstract
ABSTRACT
Midbrain dopaminergic (mDA) neuron development has been an intense area of research during recent years. This is due in part to a growing interest in regenerative medicine and the hope that treatment for diseases affecting mDA neurons, such as Parkinson's disease (PD), might be facilitated by a better understanding of how these neurons are specified, differentiated and maintained in vivo. This knowledge might help to instruct efforts to generate mDA neurons in vitro, which holds promise not only for cell replacement therapy, but also for disease modeling and drug discovery. In this Primer, we will focus on recent developments in understanding the molecular mechanisms that regulate the development of mDA neurons in vivo, and how they have been used to generate human mDA neurons in vitro from pluripotent stem cells or from somatic cells via direct reprogramming. Current challenges and future avenues in the development of a regenerative medicine for PD will be identified and discussed.
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Affiliation(s)
- Ernest Arenas
- Laboratory of Molecular Neurobiology, Dept. Medical Biochemistry and Biophysics, Center of Developmental Biology for Regenerative Medicine, Karolinska Institutet, Stockholm 171 77, Sweden
| | - Mark Denham
- Laboratory of Molecular Neurobiology, Dept. Medical Biochemistry and Biophysics, Center of Developmental Biology for Regenerative Medicine, Karolinska Institutet, Stockholm 171 77, Sweden
- Danish Research Institute of Translational Neuroscience, Nordic EMBL Partnership for Molecular Medicine, Aarhus University, Aarhus 8000, Denmark
| | - J. Carlos Villaescusa
- Laboratory of Molecular Neurobiology, Dept. Medical Biochemistry and Biophysics, Center of Developmental Biology for Regenerative Medicine, Karolinska Institutet, Stockholm 171 77, Sweden
- Institute of Experimental Biology, Faculty of Science, Masaryk University, Brno 61137, Czech Republic
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21
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Interaction between Oc-1 and Lmx1a promotes ventral midbrain dopamine neural stem cells differentiation into dopamine neurons. Brain Res 2015; 1608:40-50. [PMID: 25747864 DOI: 10.1016/j.brainres.2015.02.046] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2014] [Revised: 02/23/2015] [Accepted: 02/24/2015] [Indexed: 12/20/2022]
Abstract
Recent studies have shown that Onecut (Oc) transcription factors may be involved in the early development of midbrain dopaminergic neurons (mdDA). The expression profile of Oc factors matches that of Lmx1a, an important intrinsic transcription factor in the development of mDA neuron. Moreover, the Wnt1-Lmx1a pathway controls the mdDA differentiation. However, their expression dynamics and molecular mechanisms remain to be determined. To address these issues, we hypothesize that cross-talk between Oc-1 and Lmx1a regulates the mdDA specification and differentiation through the canonical Wnt-β-catenin pathway. We found that Oc-1 and Lmx1a displayed a very similar expression profile from embryonic to adult ventral midbrain (VM) tissues. Oc-1 regulated the proliferation and differentiation of ventral midbrain neural stem cells (vmNSCs). Downregulation of Oc-1 decreased both transcript and protein level of Lmx1a. Oc-1 interacted with lmx1a in vmNSCs in vitro and in VM tissues in vivo. Knockdown of Lmx1a reduced the expression of Oc-1 and Wnt1 in vmNSCs. Inhibiting Wnt1 signaling in vmNSCs provoked similar responses. Our data suggested that Oc-1 interacts with Lmx1a to promote vmNSCs differentiation into dopamine neuron through Wnt1-Lmx1a pathway.
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22
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Mesman S, von Oerthel L, Smidt MP. Mesodiencephalic dopaminergic neuronal differentiation does not involve GLI2A-mediated SHH-signaling and is under the direct influence of canonical WNT signaling. PLoS One 2014; 9:e97926. [PMID: 24865218 PMCID: PMC4035267 DOI: 10.1371/journal.pone.0097926] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Accepted: 04/27/2014] [Indexed: 12/19/2022] Open
Abstract
Sonic Hedgehog (SHH) and WNT proteins are key regulators in many developmental processes, like embryonic patterning and brain development. In the brain, SHH is expressed in a gradient starting in the floor plate (FP) progressing ventrally in the midbrain, where it is thought to be involved in the development and specification of mesodiencephalic dopaminergic (mdDA) neurons. GLI2A-mediated SHH-signaling induces the expression of Gli1, which is inhibited when cells start expressing SHH themselves. To determine whether mdDA neurons receive GLI2A-mediated SHH-signaling during differentiation, we used a BAC-transgenic mouse model expressing eGFP under the control of the Gli1 promoter. This mouse-model allowed for mapping of GLI2A-mediated SHH-signaling temporal and spatial in the mouse midbrain. Since mdDA neurons are born from E10.5, peaking at E11.0–E12.0, we examined Gli1-eGFP embryos at E11.5, E12.5, and E13.5, indicating whether Gli1 was induced before or during mdDA development and differentiation. Our data indicate that GLI2A-mediated SHH-signaling is not involved in mdDA neuronal differentiation. However, it appears to be involved in the differentiation of neurons which make up a subset of the red nucleus (RN). In order to detect whether mdDA neuronal differentiation may be under the control of canonical WNT-signaling, we used a transgenic mouse-line expressing LacZ under the influence of stable β-catenin. Here, we show that TH+ neurons of the midbrain receive canonical WNT-signaling during differentiation. Therefore, we suggest that early SHH-signaling is indirectly involved in mdDA development through early patterning of the midbrain area, whereas canonical WNT-signaling is directly involved in the differentiation of the mdDA neuronal population.
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Affiliation(s)
- Simone Mesman
- Swammerdam Institute for Life Sciences, CNS, FNWI University of Amsterdam, Amsterdam, The Netherlands
| | - Lars von Oerthel
- Swammerdam Institute for Life Sciences, CNS, FNWI University of Amsterdam, Amsterdam, The Netherlands
| | - Marten P. Smidt
- Swammerdam Institute for Life Sciences, CNS, FNWI University of Amsterdam, Amsterdam, The Netherlands
- * E-mail:
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23
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Bodea GO, Spille JH, Abe P, Andersson AS, Acker-Palmer A, Stumm R, Kubitscheck U, Blaess S. Reelin and CXCL12 regulate distinct migratory behaviors during the development of the dopaminergic system. Development 2014; 141:661-73. [PMID: 24449842 DOI: 10.1242/dev.099937] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The proper functioning of the dopaminergic system requires the coordinated formation of projections extending from dopaminergic neurons in the substantia nigra (SN), ventral tegmental area (VTA) and retrorubral field to a wide array of forebrain targets including the striatum, nucleus accumbens and prefrontal cortex. The mechanisms controlling the assembly of these distinct dopaminergic cell clusters are not well understood. Here, we have investigated in detail the migratory behavior of dopaminergic neurons giving rise to either the SN or the medial VTA using genetic inducible fate mapping, ultramicroscopy, time-lapse imaging, slice culture and analysis of mouse mutants. We demonstrate that neurons destined for the SN migrate first radially and then tangentially, whereas neurons destined for the medial VTA undergo primarily radial migration. We show that tangentially migrating dopaminergic neurons express the components of the reelin signaling pathway, whereas dopaminergic neurons in their initial, radial migration phase express CXC chemokine receptor 4 (CXCR4), the receptor for the chemokine CXC motif ligand 12 (CXCL12). Perturbation of reelin signaling interferes with the speed and orientation of tangentially, but not radially, migrating dopaminergic neurons and results in severe defects in the formation of the SN. By contrast, CXCR4/CXCL12 signaling modulates the initial migration of dopaminergic neurons. With this study, we provide the first molecular and functional characterization of the distinct migratory pathways taken by dopaminergic neurons destined for SN and VTA, and uncover mechanisms that regulate different migratory behaviors of dopaminergic neurons.
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Affiliation(s)
- Gabriela Oana Bodea
- Institute of Reconstructive Neurobiology, Life and Brain Center, University of Bonn, Sigmund-Freud-Strasse 25, 53127 Bonn, Germany
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24
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Arenas E. Wnt signaling in midbrain dopaminergic neuron development and regenerative medicine for Parkinson's disease. J Mol Cell Biol 2014; 6:42-53. [DOI: 10.1093/jmcb/mju001] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
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25
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Wurst W, Prakash N. Wnt1-regulated genetic networks in midbrain dopaminergic neuron development. J Mol Cell Biol 2013; 6:34-41. [DOI: 10.1093/jmcb/mjt046] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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26
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Yang J, Brown A, Ellisor D, Paul E, Hagan N, Zervas M. Dynamic temporal requirement of Wnt1 in midbrain dopamine neuron development. Development 2013; 140:1342-52. [PMID: 23444360 DOI: 10.1242/dev.080630] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Wnt1-expressing progenitors generate midbrain dopamine (MbDA) and cerebellum (Cb) neurons in distinct temporal windows and from spatially discrete progenitor domains. It has been shown that Wnt1 and Lmx1a participate in a cross-regulatory loop that is utilized during MbDA neuron development. However, Wnt1 expression dynamically changes over time and precedes that of Lmx1a. The spatial and temporal requirements of Wnt1 in development and specifically its requirement for MbDA neurons remain to be determined. To address these issues, we generated a conditional Wnt1 allele and temporally deleted Wnt1 coupled with genetic lineage analysis. Using this approach, we show that patterning of the midbrain (Mb) and Cb by Wnt1 occurs between the one-somite and the six- to eight-somite stages and is solely dependent on Wnt1 function in the Mb, but not in the Cb. Interestingly, an En1-derived domain persists after the early deletion of Wnt1 and mutant cells express OTX2. However, the En1-derived Wnt1-mutant domain does not contain LMX1a-expressing progenitors, and MbDA neurons are depleted. Thus, we demonstrate an early requirement of Wnt1 for all MbDA neurons. Subsequently, we deleted Wnt1 in the ventral Mb and show a continued late requirement for Wnt1 in MbDA neuron development, but not in LMX1a-expressing progenitors. Specifically, Wnt1 deletion disrupts the birthdating of MbDA neurons and causes a depletion of MbDA neurons positioned medially and a concomitant expansion of MbDA neurons positioned laterally during embryogenesis. Collectively, our analyses resolve the spatial and temporal function of Wnt1 in Mb and Cb patterning and in MbDA neuron development in vivo.
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Affiliation(s)
- Jasmine Yang
- Department of Molecular Biology, Cell Biology and Biochemistry, Division of Biology and Medicine, Brown University, 70 Ship Street, Providence, RI 02903, USA
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27
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Ellisor D, Rieser C, Voelcker B, Machan JT, Zervas M. Genetic dissection of midbrain dopamine neuron development in vivo. Dev Biol 2012; 372:249-62. [PMID: 23041116 DOI: 10.1016/j.ydbio.2012.09.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Revised: 09/10/2012] [Accepted: 09/23/2012] [Indexed: 11/27/2022]
Abstract
Midbrain dopamine (MbDA) neurons are partitioned into medial and lateral cohorts that control complex functions. However, the genetic underpinnings of MbDA neuron heterogeneity are unclear. While it is known that Wnt1-expressing progenitors contribute to MbDA neurons, the role of Wnt1 in MbDA neuron development in vivo is unresolved. We show that mice with a spontaneous point mutation in Wnt1 have a unique phenotype characterized by the loss of medial MbDA neurons concomitant with a severe depletion of Wnt1-expressing progenitors and diminished LMX1a-expressing progenitors. Wnt1 mutant embryos also have alterations in a hierarchical gene regulatory loop suggesting multiple gene involvement in the Wnt1 mutant MbDA neuron phenotype. To investigate this possibility, we conditionally deleted Gbx2, Fgf8, and En1/2 after their early role in patterning and asked whether these genetic manipulations phenocopied the depletion of MbDA neurons in Wnt1 mutants. The conditional deletion of Gbx2 did not result in re-positioning or distribution of MbDA neurons. The temporal deletion of Fgf8 did not result in the loss of either LMX1a-expressing progenitors nor the initial population of differentiated MbDA neurons, but did result in a complete loss of MbDA neurons at later stages. The temporal deletion and species specific manipulation of En1/2 demonstrated a continued and species specific role of Engrailed genes in MbDA neuron development. Notably, our conditional deletion experiments revealed phenotypes dissimilar to Wnt1 mutants indicating the unique role of Wnt1 in MbDA neuron development. By placing Wnt1, Fgf8, and En1/2 in the context of their temporal requirement for MbDA neuron development, we further deciphered the developmental program underpinning MbDA neuron progenitors.
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Affiliation(s)
- Debra Ellisor
- Department of Molecular Biology, Cell Biology and Biochemistry, Division of Biology and Medicine, Brown University, 70 Ship St., Providence, RI 02903, USA
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28
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Hagan N, Zervas M. Wnt1 expression temporally allocates upper rhombic lip progenitors and defines their terminal cell fate in the cerebellum. Mol Cell Neurosci 2012; 49:217-29. [PMID: 22173107 PMCID: PMC3351839 DOI: 10.1016/j.mcn.2011.11.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Revised: 10/30/2011] [Accepted: 11/28/2011] [Indexed: 01/07/2023] Open
Abstract
The cerebellum (Cb) controls movement related physiology using a diverse array of morphologically and biochemically distinct neurons. During development, the Cb is derived from rhombomere 1 (r1), an embryonic compartment patterned by a signaling center referred to as the isthmus organizer. The secreted glycoprotein WNT1 is expressed in the midbrain primordia (mesencephalon, mes) and at the posterior limit of the mes. WNT1 plays a pivotal role in maintaining the isthmus organizer and mutations in Wnt1 produce severe Cb defects that are generally attributed to aberrant organizer activity. Interestingly, Wnt1 is also expressed at the most posterior limit of dorsal r1, in a region known as the upper rhombic lip (URL). However, the distribution and molecular identity of Wnt1 expressing progenitors have not been carefully described in r1. We used Wnt1-Venus transgenic mice to generate a molecular map of Wnt1 expressing progenitors in relation to other well characterized Cb biomarkers such as MATH1 (ATOH1), LMX1a and OTX2. Our analysis validated Wnt1 expression in the URL and revealed molecularly-defined developmental zones in r1. We then used genetic inducible fate mapping (GIFM) to link transient Wnt1 expression in r1 to terminal cell fates in the mature Cb. Wnt1 expressing progenitors primarily contributed to neurons in deep cerebellar nuclei, granule cells, and unipolar brush cells in distinct but overlapping temporal windows and sparsely contributed to inhibitory neurons and Bergmann glia. We further demonstrate that the Wnt1 lineage does not follow a competency model of progressive lineage restriction to generate the Cb or the functionally related precerebellar system. Instead, progenitors initiate Wnt1 expression de novo to give rise to each Cb cell type and precerebellar nuclei. We also used GIFM to determine how the temporal control of Wnt1 expression is related to molecular identity and cell migration in Cb development. Our findings provide new insight into how lineage and timing establish cell diversity within the Cb system.
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Affiliation(s)
- Nellwyn Hagan
- Department of Neuroscience, Division of Biology and Medicine, Brown University, Providence, RI 02903, USA
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