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Hernandez-Morato I, Koss S, Honzel E, Pitman MJ. Netrin-1 as A neural guidance protein in development and reinnervation of the larynx. Ann Anat 2024; 254:152247. [PMID: 38458575 DOI: 10.1016/j.aanat.2024.152247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 02/01/2024] [Accepted: 03/05/2024] [Indexed: 03/10/2024]
Abstract
Neural guidance proteins participate in motor neuron migration, axonal projection, and muscle fiber innervation during development. One of the guidance proteins that participates in axonal pathfinding is Netrin-1. Despite the well-known role of Netrin-1 in embryogenesis of central nervous tissue, it is still unclear how the expression of this guidance protein contributes to primary innervation of the periphery, as well as reinnervation. This is especially true in the larynx where Netrin-1 is upregulated within the intrinsic laryngeal muscles after nerve injury and where blocking of Netrin-1 alters the pattern of reinnervation of the intrinsic laryngeal muscles. Despite this consistent finding, it is unknown how Netrin-1 expression contributes to guidance of the axons towards the larynx. Improved knowledge of Netrin-1's role in nerve regeneration and reinnervation post-injury in comparison to its role in primary innervation during embryological development, may provide insights in the search for therapeutics to treat nerve injury. This paper reviews the known functions of Netrin-1 during the formation of the central nervous system and during cranial nerve primary innervation. It also describes the role of Netrin-1 in the formation of the larynx and during recurrent laryngeal reinnervation following nerve injury in the adult.
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Affiliation(s)
- Ignacio Hernandez-Morato
- Department of Otolaryngology-Head & Neck Surgery, The Center for Voice and Swallowing, Columbia University College of Physicians and Surgeons, New York, NY, United States; Department of Anatomy and Embryology, School of Medicine, Complutense University of Madrid, Madrid, Madrid, Spain.
| | - Shira Koss
- ENT Associates of Nassau County, Levittown, NY, United States
| | - Emily Honzel
- Department of Otolaryngology-Head & Neck Surgery, The Center for Voice and Swallowing, Columbia University College of Physicians and Surgeons, New York, NY, United States
| | - Michael J Pitman
- Department of Otolaryngology-Head & Neck Surgery, The Center for Voice and Swallowing, Columbia University College of Physicians and Surgeons, New York, NY, United States
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2
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Fritzsch B. Evolution and development of extraocular motor neurons, nerves and muscles in vertebrates. Ann Anat 2024; 253:152225. [PMID: 38346566 DOI: 10.1016/j.aanat.2024.152225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 01/16/2024] [Accepted: 02/05/2024] [Indexed: 02/17/2024]
Abstract
The purpose of this review is to analyze the origin of ocular motor neurons, define the pattern of innervation of nerve fibers that project to the extraocular eye muscles (EOMs), describe congenital disorders that alter the development of ocular motor neurons, and provide an overview of vestibular pathway inputs to ocular motor nuclei. Six eye muscles are innervated by axons of three ocular motor neurons, the oculomotor (CNIII), trochlear (CNIV), and abducens (CNVI) neurons. Ocular motor neurons (CNIII) originate in the midbrain and innervate the ipsilateral orbit, except for the superior rectus and the levator palpebrae, which are contralaterally innervated. Trochlear motor neurons (CNIV) originate at the midbrain-hindbrain junction and innervate the contralateral superior oblique muscle. Abducens motor neurons (CNVI) originate variously in the hindbrain of rhombomeres r4-6 that innervate the posterior (or lateral) rectus muscle and innervate the retractor bulbi. Genes allow a distinction between special somatic (CNIII, IV) and somatic (CNVI) ocular motor neurons. Development of ocular motor neurons and their axonal projections to the EOMs may be derailed by various genetic causes, resulting in the congenital cranial dysinnervation disorders. The ocular motor neurons innervate EOMs while the vestibular nuclei connect with the midbrain-brainstem motor neurons.
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Affiliation(s)
- Bernd Fritzsch
- Department of Neurological Sciences, University of Nebraska Medical Center, NE, USA.
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3
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Isabella AJ, Moens CB. Development and regeneration of the vagus nerve. Semin Cell Dev Biol 2024; 156:219-227. [PMID: 37537116 PMCID: PMC10830892 DOI: 10.1016/j.semcdb.2023.07.008] [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: 10/09/2022] [Revised: 07/13/2023] [Accepted: 07/20/2023] [Indexed: 08/05/2023]
Abstract
The vagus nerve, with its myriad constituent axon branches and innervation targets, has long been a model of anatomical complexity in the nervous system. The branched architecture of the vagus nerve is now appreciated to be highly organized around the topographic and/or molecular identities of the neurons that innervate each target tissue. However, we are only just beginning to understand the developmental mechanisms by which heterogeneous vagus neuron identity is specified, patterned, and used to guide the axons of particular neurons to particular targets. Here, we summarize our current understanding of the complex topographic and molecular organization of the vagus nerve, the developmental basis of neuron specification and patterned axon guidance that supports this organization, and the regenerative mechanisms that promote, or inhibit, the restoration of vagus nerve organization after nerve damage. Finally, we highlight key unanswered questions in these areas and discuss potential strategies to address these questions.
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Affiliation(s)
- Adam J Isabella
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA.
| | - Cecilia B Moens
- Basic Sciences Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA.
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Hani T, Fujita K, Kudo T, Taya Y, Sato K, Soeno Y. Tissue-Targeted Transcriptomics Reveals SEMA3D Control of Hypoglossal Nerve Projection to Mouse Tongue Primordia. Acta Histochem Cytochem 2024; 57:35-46. [PMID: 38463205 PMCID: PMC10918430 DOI: 10.1267/ahc.23-00073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Accepted: 01/16/2024] [Indexed: 03/12/2024] Open
Abstract
The mouse hypoglossal nerve originates in the occipital motor nuclei at embryonic day (E)10.5 and projects a long distance, reaching the vicinity of the tongue primordia, the lateral lingual swellings, at E11.5. However, the details of how the hypoglossal nerve correctly projects to the primordia are poorly understood. To investigate the molecular basis of hypoglossal nerve elongation, we used a novel transcriptomic approach using the ROKU method. The ROKU algorithm identified 3825 genes specific for lateral lingual swellings at E11.5, of which 34 genes were predicted to be involved in axon guidance. Ingenuity Pathway Analysis-assisted enrichment revealed activation of the semaphorin signaling pathway during tongue development, and quantitative PCR showed that the expressions of Sema3d and Nrp1 in this pathway peaked at E11.5. Immunohistochemistry detected NRP1 in the hypoglossal nerve and SEMA3D as tiny granules in the extracellular space beneath the epithelium of the tongue primordia and in lateral and anterior regions of the mandibular arch. Fewer SEMA3D granules were localized around hypoglossal nerve axons and in the space where they elongated. In developing tongue primordia, tissue-specific regulation of SEMA3D might control the route of hypoglossal nerve projection via its repulsive effect on NRP1.
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Affiliation(s)
- Taisuke Hani
- Department of Pathology, The Nippon Dental University, School of Life Dentistry at Tokyo, 1-9-20, Fujimi, Chiyoda-ku, 102-8159 Tokyo, Japan
| | - Kazuya Fujita
- Department of Pathology, The Nippon Dental University, School of Life Dentistry at Tokyo, 1-9-20, Fujimi, Chiyoda-ku, 102-8159 Tokyo, Japan
| | - Tomoo Kudo
- Department of Pathology, The Nippon Dental University, School of Life Dentistry at Tokyo, 1-9-20, Fujimi, Chiyoda-ku, 102-8159 Tokyo, Japan
| | - Yuji Taya
- Department of Pathology, The Nippon Dental University, School of Life Dentistry at Tokyo, 1-9-20, Fujimi, Chiyoda-ku, 102-8159 Tokyo, Japan
| | - Kaori Sato
- Department of Pathology, The Nippon Dental University, School of Life Dentistry at Tokyo, 1-9-20, Fujimi, Chiyoda-ku, 102-8159 Tokyo, Japan
| | - Yuuichi Soeno
- Department of Pathology, The Nippon Dental University, School of Life Dentistry at Tokyo, 1-9-20, Fujimi, Chiyoda-ku, 102-8159 Tokyo, Japan
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5
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Honzel E, Hernandez-Morato I, Joshi A, Pennington-Fitzgerald W, Moayedi Y, Pitman MJ. Temporal Expression of Hox Genes and Phox2b in the Rat Nucleus Ambiguus During Development: Implications on Laryngeal Innervation. Laryngoscope 2023; 133:3462-3471. [PMID: 37350386 PMCID: PMC10907063 DOI: 10.1002/lary.30826] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 06/02/2023] [Accepted: 06/05/2023] [Indexed: 06/24/2023]
Abstract
OBJECTIVES Recurrent laryngeal nerve (RLN) injury results in synkinetic reinnervation and vocal fold paralysis. Investigation of cues expressed in the developing brainstem that influence correct selective targeting of intrinsic laryngeal muscles may elucidate post-injury abnormalities contributing to non-functional reinnervation. Primary targets of interest were Hoxb1 and Hoxb2, members of the Hox family that create overlapping gradients in the developing brain, and their target Phox2b, a transcription factor necessary for cranial nerve branchio- and visceromotoneuron survival. METHODS Rat embryos at developmental days E14, E16, E18, and E20 (4 animals/age) were sectioned for RNA in situ hybridization to detect Hoxb1, Hoxb2, and Phox2b mRNA within the brainstem. Slides were costained with Islet1 antibody for identification of the nucleus ambiguus. Results were confirmed using immunohistochemistry. Sections were imaged on a confocal microscope. RNA and protein expressions were quantified using QuPath. Statistical analyses were performed using R. RESULTS Hoxb1, Hoxb2, and Phox2b expressions varied according to embryologic age. Hoxb1 and Hoxb2 expression peaked at E16, with significant decreases at E18 and E20 (one-way ANOVA p = 0.001 for both). Phox2b expression was highest at E14 and trended downward with increased embryologic age (one-way ANOVA p = 0.005). CONCLUSION Peak expression of Hoxb1 and Hoxb2 is observed at time points when the RLN arrives at the larynx and begins to branch toward individual muscles, positioning these gene products to be involved in cueing laryngeal motoneuron identity and target identification. Higher expression of Phox2b earlier in development suggests a role in laryngeal motoneuron formation. LEVEL OF EVIDENCE NA Laryngoscope, 133:3462-3471, 2023.
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Affiliation(s)
- Emily Honzel
- Department of Otolaryngology-Head & Neck Surgery, Columbia University College of Physicians and Surgeons, New York, New York, U.S.A
| | - Ignacio Hernandez-Morato
- Department of Otolaryngology-Head & Neck Surgery, Columbia University College of Physicians and Surgeons, New York, New York, U.S.A
| | - Abhinav Joshi
- Department of Otolaryngology-Head & Neck Surgery, Columbia University College of Physicians and Surgeons, New York, New York, U.S.A
| | - William Pennington-Fitzgerald
- Department of Otolaryngology-Head & Neck Surgery, Columbia University College of Physicians and Surgeons, New York, New York, U.S.A
| | - Yalda Moayedi
- Department of Otolaryngology-Head & Neck Surgery, Columbia University College of Physicians and Surgeons, New York, New York, U.S.A
- Department of Neurology, Columbia University, New York, New York, U.S.A
| | - Michael J Pitman
- Department of Otolaryngology-Head & Neck Surgery, Columbia University College of Physicians and Surgeons, New York, New York, U.S.A
- Department of Neurology, Columbia University, New York, New York, U.S.A
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6
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Cintrón-Rivera LG, Burns N, Patel R, Plavicki JS. Exposure to the aryl hydrocarbon receptor agonist dioxin disrupts formation of the muscle, nerves, and vasculature in the developing jaw. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 337:122499. [PMID: 37660771 DOI: 10.1016/j.envpol.2023.122499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 08/14/2023] [Accepted: 08/31/2023] [Indexed: 09/05/2023]
Abstract
Human exposure to environmental pollutants can disrupt embryonic development and impact juvenile and adult health outcomes by adversely affecting cell and organ function. Notwithstanding, environmental contamination continues to increase due to industrial development, insufficient regulations, and the mobilization of pollutants as a result of extreme weather events. Dioxins are a class of structurally related persistent organic pollutants that are highly toxic, carcinogenic, and teratogenic. 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is the most potent dioxin compound and has been shown to induce toxic effects in developing organisms by activating the aryl hydrocarbon receptor (AHR), a ligand activated transcription factor targeted by multiple persistent organic pollutants. Contaminant-induced AHR activation results in malformations of the craniofacial cartilages and neurocranium; however, the mechanisms mediating these phenotypes are not well understood. In this study, we utilized the optically transparent zebrafish model to elucidate novel cellular targets and potential transcriptional targets underlying TCDD-induced craniofacial malformations. To this end, we exposed zebrafish embryos at 4 h post fertilization to TCDD and employed a mixed-methods approach utilizing immunohistochemistry staining, transgenic reporter lines, fixed and in vivo confocal imaging, and timelapse microscopy to determine the targets mediating TCDD-induced craniofacial phenotypes. Our data indicate that embryonic TCDD exposure reduced jaw and pharyngeal arch Sox10+ chondrocytes and Tcf21+ pharyngeal mesoderm progenitors. Exposure to TCDD correspondingly led to a reduction in collagen type II deposition in Sox10+ domains. Embryonic TCDD exposure impaired development of tissues derived from or guided by Tcf21+ progenitors, namely: nerves, muscle, and vasculature. Specifically, TCDD exposure disrupted development of the hyoid and mandibular arch muscles, decreased neural innervation of the jaw, resulted in compression of cranial nerves V and VII, and led to jaw vasculature malformations. Collectively, these findings reveal novel structural targets and potential transcriptional targets of TCDD-induced toxicity, showcasing how contaminant exposures lead to congenital craniofacial malformations.
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Affiliation(s)
- Layra G Cintrón-Rivera
- Department of Pathology and Laboratory Medicine, Brown University, 70 Ship St, Providence, RI, 02903, USA
| | - Nicole Burns
- Department of Pathology and Laboratory Medicine, Brown University, 70 Ship St, Providence, RI, 02903, USA
| | - Ratna Patel
- Department of Pathology and Laboratory Medicine, Brown University, 70 Ship St, Providence, RI, 02903, USA
| | - Jessica S Plavicki
- Department of Pathology and Laboratory Medicine, Brown University, 70 Ship St, Providence, RI, 02903, USA.
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7
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Tenney AP, Di Gioia SA, Webb BD, Chan WM, de Boer E, Garnai SJ, Barry BJ, Ray T, Kosicki M, Robson CD, Zhang Z, Collins TE, Gelber A, Pratt BM, Fujiwara Y, Varshney A, Lek M, Warburton PE, Van Ryzin C, Lehky TJ, Zalewski C, King KA, Brewer CC, Thurm A, Snow J, Facio FM, Narisu N, Bonnycastle LL, Swift A, Chines PS, Bell JL, Mohan S, Whitman MC, Staffieri SE, Elder JE, Demer JL, Torres A, Rachid E, Al-Haddad C, Boustany RM, Mackey DA, Brady AF, Fenollar-Cortés M, Fradin M, Kleefstra T, Padberg GW, Raskin S, Sato MT, Orkin SH, Parker SCJ, Hadlock TA, Vissers LELM, van Bokhoven H, Jabs EW, Collins FS, Pennacchio LA, Manoli I, Engle EC. Noncoding variants alter GATA2 expression in rhombomere 4 motor neurons and cause dominant hereditary congenital facial paresis. Nat Genet 2023; 55:1149-1163. [PMID: 37386251 PMCID: PMC10335940 DOI: 10.1038/s41588-023-01424-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 05/10/2023] [Indexed: 07/01/2023]
Abstract
Hereditary congenital facial paresis type 1 (HCFP1) is an autosomal dominant disorder of absent or limited facial movement that maps to chromosome 3q21-q22 and is hypothesized to result from facial branchial motor neuron (FBMN) maldevelopment. In the present study, we report that HCFP1 results from heterozygous duplications within a neuron-specific GATA2 regulatory region that includes two enhancers and one silencer, and from noncoding single-nucleotide variants (SNVs) within the silencer. Some SNVs impair binding of NR2F1 to the silencer in vitro and in vivo and attenuate in vivo enhancer reporter expression in FBMNs. Gata2 and its effector Gata3 are essential for inner-ear efferent neuron (IEE) but not FBMN development. A humanized HCFP1 mouse model extends Gata2 expression, favors the formation of IEEs over FBMNs and is rescued by conditional loss of Gata3. These findings highlight the importance of temporal gene regulation in development and of noncoding variation in rare mendelian disease.
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Affiliation(s)
- Alan P Tenney
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
| | - Silvio Alessandro Di Gioia
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
- Regeneron Pharmaceuticals, Tarrytown, NY, USA
| | - Bryn D Webb
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Wai-Man Chan
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Elke de Boer
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Sarah J Garnai
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
- Harvard-MIT Health Sciences and Technology, Harvard Medical School, Boston, MA, USA
| | - Brenda J Barry
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Tammy Ray
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Michael Kosicki
- Environmental Genomics & System Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Caroline D Robson
- Department of Radiology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Zhongyang Zhang
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Thomas E Collins
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Alon Gelber
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Brandon M Pratt
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Yuko Fujiwara
- Dana-Farber/Boston Children's Cancer and Blood Disorders Center, Boston, MA, USA
| | - Arushi Varshney
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA
| | - Monkol Lek
- Department of Genetics, Yale University School of Medicine, New Haven, CT, USA
| | - Peter E Warburton
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Center for Advanced Genomics Technology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Carol Van Ryzin
- Metabolic Medicine Branch, National Human Genome Research Institute, NIH, Bethesda, MD, USA
| | - Tanya J Lehky
- EMG Section, National Institute of Neurological Disorders and Stroke, NIH, Bethesda, MD, USA
| | - Christopher Zalewski
- Audiology Unit, Otolaryngology Branch, National Institute on Deafness and Other Communication Disorders, NIH, Bethesda, MD, USA
| | - Kelly A King
- Audiology Unit, Otolaryngology Branch, National Institute on Deafness and Other Communication Disorders, NIH, Bethesda, MD, USA
| | - Carmen C Brewer
- Audiology Unit, Otolaryngology Branch, National Institute on Deafness and Other Communication Disorders, NIH, Bethesda, MD, USA
| | - Audrey Thurm
- Neurodevelopmental and Behavioral Phenotyping Service, National Institute of Mental Health, NIH, Bethesda, MD, USA
| | - Joseph Snow
- Office of the Clinical Director, National Institute of Mental Health, NIH, Bethesda, MD, USA
| | - Flavia M Facio
- Center for Precision Health Research, National Human Genome Research Institute, NIH, Bethesda, MD, USA
- Invitae Corporation, San Francisco, CA, USA
| | - Narisu Narisu
- Center for Precision Health Research, National Human Genome Research Institute, NIH, Bethesda, MD, USA
| | - Lori L Bonnycastle
- Center for Precision Health Research, National Human Genome Research Institute, NIH, Bethesda, MD, USA
| | - Amy Swift
- Center for Precision Health Research, National Human Genome Research Institute, NIH, Bethesda, MD, USA
| | - Peter S Chines
- Center for Precision Health Research, National Human Genome Research Institute, NIH, Bethesda, MD, USA
| | - Jessica L Bell
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Suresh Mohan
- Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA
| | - Mary C Whitman
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Sandra E Staffieri
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, and University of Melbourne, Melbourne, Victoria, Australia
- Department of Ophthalmology, Royal Children's Hospital, Parkville, Victoria, Australia
| | - James E Elder
- Department of Ophthalmology, Royal Children's Hospital, Parkville, Victoria, Australia
| | - Joseph L Demer
- Stein Eye Institute and Departments of Ophthalmology, Neurology, and Bioengineering, University of California, Los Angeles, Los Angeles, CA, USA
| | - Alcy Torres
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
- Department of Pediatrics, Boston Medical Center, Boston University Aram V. Chobanian & Edward Avedisian School of Medicine, Boston, MA, USA
| | - Elza Rachid
- Department of Ophthalmology, American University of Beirut Medical Center, Beirut, Lebanon
| | - Christiane Al-Haddad
- Department of Ophthalmology, American University of Beirut Medical Center, Beirut, Lebanon
| | - Rose-Mary Boustany
- Pediatrics & Adolescent Medicine/Biochemistry & Molecular Genetics, American University of Beirut Medical Center, Beirut, Lebanon
| | - David A Mackey
- Lions Eye Institute, University of Western Australia, Perth, Australia
| | - Angela F Brady
- North West Thames Regional Genetics Service, Northwick Park Hospital, Harrow, UK
| | - María Fenollar-Cortés
- Unidad de Genética Clínica, Instituto de Medicina del Laboratorio. IdISSC, Hospital Clínico San Carlos, Madrid, Spain
| | - Melanie Fradin
- Service de Génétique Clinique, CHU Rennes, Centre Labellisé Anomalies du Développement, Rennes, France
| | - Tjitske Kleefstra
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, the Netherlands
- Center of Excellence for Neuropsychiatry, Vincent van Gogh Institute for Psychiatry, Venray, the Netherlands
| | - George W Padberg
- Department of Neurology, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Salmo Raskin
- Centro de Aconselhamento e Laboratório Genetika, Curitiba, Paraná, Brazil
| | - Mario Teruo Sato
- Department of Ophthalmology & Otorhinolaryngology, Federal University of Paraná, Curitiba, Paraná, Brazil
| | - Stuart H Orkin
- Howard Hughes Medical Institute, Chevy Chase, MD, USA
- Dana-Farber/Boston Children's Cancer and Blood Disorders Center, Boston, MA, USA
| | - Stephen C J Parker
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI, USA
| | - Tessa A Hadlock
- Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA
| | - Lisenka E L M Vissers
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Hans van Bokhoven
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, the Netherlands
- Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Ethylin Wang Jabs
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
- Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Francis S Collins
- Center for Precision Health Research, National Human Genome Research Institute, NIH, Bethesda, MD, USA
| | - Len A Pennacchio
- Environmental Genomics & System Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Irini Manoli
- Metabolic Medicine Branch, National Human Genome Research Institute, NIH, Bethesda, MD, USA
| | - Elizabeth C Engle
- Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA.
- F.M. Kirby Neurobiology Center, Boston Children's Hospital, Boston, MA, USA.
- Howard Hughes Medical Institute, Chevy Chase, MD, USA.
- Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA.
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8
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McArthur KL, Tovar VM, Griffin-Baldwin E, Tovar BD, Astad EK. Early development of respiratory motor circuits in larval zebrafish (Danio rerio). J Comp Neurol 2023; 531:838-852. [PMID: 36881713 PMCID: PMC10081962 DOI: 10.1002/cne.25467] [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: 07/07/2022] [Revised: 11/15/2022] [Accepted: 02/07/2023] [Indexed: 03/09/2023]
Abstract
Rhythm-generating circuits in the vertebrate hindbrain form synaptic connections with cranial and spinal motor neurons, to generate coordinated, patterned respiratory behaviors. Zebrafish provide a uniquely tractable model system to investigate the earliest stages in respiratory motor circuit development in vivo. In larval zebrafish, respiratory behaviors are carried out by muscles innervated by cranial motor neurons-including the facial branchiomotor neurons (FBMNs), which innervate muscles that move the jaw, buccal cavity, and operculum. However, it is unclear when FBMNs first receive functional synaptic input from respiratory pattern-generating neurons, and how the functional output of the respiratory motor circuit changes across larval development. In the current study, we used behavior and calcium imaging to determine how early FBMNs receive functional synaptic inputs from respiratory pattern-generating networks in larval zebrafish. Zebrafish exhibited patterned operculum movements by 3 days postfertilization (dpf), though this behavior became more consistent at 4 and 5 dpf. Also by 3dpf, FBMNs fell into two distinct categories ("rhythmic" and "nonrhythmic"), based on patterns of neural activity. These two neuron categories were arranged differently along the dorsoventral axis, demonstrating that FBMNs have already established dorsoventral topography by 3 dpf. Finally, operculum movements were coordinated with pectoral fin movements at 3 dpf, indicating that the operculum behavioral pattern was driven by synaptic input. Taken together, this evidence suggests that FBMNs begin to receive initial synaptic input from a functional respiratory central pattern generator at or prior to 3 dpf. Future studies will use this model to study mechanisms of normal and abnormal respiratory circuit development.
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Affiliation(s)
| | | | | | - Bria D. Tovar
- Biology Department, Southwestern University, Georgetown, TX 78626
| | - Emma K. Astad
- Biology Department, Southwestern University, Georgetown, TX 78626
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9
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Ghosal R, Borrego-Soto G, Eberhart JK. Embryonic ethanol exposure disrupts craniofacial neuromuscular integration in zebrafish larvae. Front Physiol 2023; 14:1131075. [PMID: 36824468 PMCID: PMC9941677 DOI: 10.3389/fphys.2023.1131075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2022] [Accepted: 01/24/2023] [Indexed: 02/10/2023] Open
Abstract
Forming a vertebrate head involves the meticulous integration of multiple tissue types during development. Prenatal alcohol exposure is known to cause a variety of birth defects, especially to tissues in the vertebrate head. However, a systematic analysis of coordinated defects across tissues in the head is lacking. Here, we delineate the effects of ethanol on individual tissue types and their integration during craniofacial development. We found that exposure to 1% ethanol induced ectopic cranial muscle and nerve defects with only slight effects on skeletal pattern. Ectopic muscles were, however, unaccompanied by ectopic tendons and could be partially rescued by anesthetizing the larvae before muscle fibers appeared. This finding suggests that the ectopic muscles result from fiber detachment and are not due to an underlying muscle patterning defect. Interestingly, immobilization did not rescue the nerve defects, thus ethanol has an independent effect on each tissue even though they are linked in developmental time and space. Time-course experiments demonstrated an increase in nerve defects with ethanol exposure between 48hpf-4dpf. Time-lapse imaging confirmed the absence of nerve pathfinding or misrouting defects until 48hpf. These results indicate that ethanol-induced nerve defects occur at the time of muscle innervation and after musculoskeletal patterning. Further, we investigated the effect of ethanol on the neuromuscular junctions of the craniofacial muscles and found a reduced number of postsynaptic receptors with no significant effect on the presynaptic terminals. Our study shows that craniofacial soft tissues are particularly susceptible to ethanol-induced damage and that these defects appear independent from one another. Thus, the effects of ethanol on the vertebrate head appear highly pleiotropic.
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Affiliation(s)
| | | | - Johann K. Eberhart
- Department of Molecular Biosciences, College of Natural Sciences and Waggoner Center for Alcohol and Addiction Research, University of Texas at Austin, Austin, TX, United States
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10
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Luderman LN, Michaels MT, Levic DS, Knapik EW. Zebrafish Erc1b mediates motor innervation and organization of craniofacial muscles in control of jaw movement. Dev Dyn 2023; 252:104-123. [PMID: 35708710 DOI: 10.1002/dvdy.511] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 05/31/2022] [Accepted: 06/03/2022] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND Movement of the lower jaw, a common behavior observed among vertebrates, is required for eating and processing food. This movement is controlled by signals sent from the trigeminal motor nerve through neuromuscular junctions (NMJs) to the masticatory muscles. Dysfunctional jaw movements contribute to craniomandibular disorders, yet the pathophysiology of these disorders is not well understood, as limited studies have been conducted on the molecular mechanisms of jaw movement. RESULTS Using erc1b/kimm533 genetic loss of function mutant, we evaluated lower jaw muscle organization and innervation by the cranial motor nerves in developing zebrafish. Using time-lapse confocal imaging of the erc1b mutant in a transgenic fluorescent reporter line, we found delayed trigeminal nerve growth and disrupted nerve branching architecture during muscle innervation. By automated 3D image analysis of NMJ distribution, we identified an increased number of small, disorganized NMJ clusters in erc1b mutant larvae compared to WT siblings. Using genetic replacement experiments, we determined the Rab GTPase binding domain of Erc1b is required for cranial motor nerve branching, but not NMJ organization or muscle attachment. CONCLUSIONS We identified Erc1b/ERC1 as a novel component of a genetic pathway contributing to muscle organization, trigeminal nerve outgrowth, and NMJ spatial distribution during development that is required for jaw movement.
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Affiliation(s)
- Lauryn N Luderman
- Division of Genetic Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, USA
- Department of Cell Biology, Duke University Medical Center, Durham, North Carolina, USA
| | - Mackenzie T Michaels
- Division of Genetic Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Daniel S Levic
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, USA
- Department of Cell Biology, Duke University Medical Center, Durham, North Carolina, USA
- Neuroscience Graduate Program, Vanderbilt Brain Institute, Vanderbilt University, Nashville, Tennessee, USA
| | - Ela W Knapik
- Division of Genetic Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, USA
- Department of Cell Biology, Duke University Medical Center, Durham, North Carolina, USA
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11
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Hummel D, Becks A, Men H, Bryda EC, Glasco DM, Chandrasekhar A. Celsr1 suppresses Wnt5a-mediated chemoattraction to prevent incorrect rostral migration of facial branchiomotor neurons. Development 2022; 149:282111. [PMID: 36325991 PMCID: PMC9845735 DOI: 10.1242/dev.200553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 10/20/2022] [Indexed: 11/06/2022]
Abstract
In the developing hindbrain, facial branchiomotor (FBM) neurons migrate caudally from rhombomere 4 (r4) to r6 to establish the circuit that drives jaw movements. Although the mechanisms regulating initiation of FBM neuron migration are well defined, those regulating directionality are not. In mutants lacking the Wnt/planar cell polarity (PCP) component Celsr1, many FBM neurons inappropriately migrate rostrally into r3. We hypothesized that Celsr1 normally blocks inappropriate rostral migration of FBM neurons by suppressing chemoattraction towards Wnt5a in r3 and successfully tested this model. First, FBM neurons in Celsr1; Wnt5a double mutant embryos never migrated rostrally, indicating that inappropriate rostral migration in Celsr1 mutants results from Wnt5a-mediated chemoattraction, which is suppressed in wild-type embryos. Second, FBM neurons migrated rostrally toward Wnt5a-coated beads placed in r3 of wild-type hindbrain explants, suggesting that excess Wnt5a chemoattractant can overcome endogenous Celsr1-mediated suppression. Third, rostral migration of FBM neurons was greatly enhanced in Celsr1 mutants overexpressing Wnt5a in r3. These results reveal a novel role for a Wnt/PCP component in regulating neuronal migration through suppression of chemoattraction.
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Affiliation(s)
- Devynn Hummel
- Division of Biological Sciences and Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Alexandria Becks
- Division of Biological Sciences and Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Hongsheng Men
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MO 65211, USA
| | - Elizabeth C. Bryda
- Department of Veterinary Pathobiology, University of Missouri, Columbia, MO 65211, USA
| | - Derrick M. Glasco
- Department of Biology, Bob Jones University, Greenville, SC 29614, USA
| | - Anand Chandrasekhar
- Division of Biological Sciences and Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA,Author for correspondence ()
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12
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Iyer NR, Shin J, Cuskey S, Tian Y, Nicol NR, Doersch TE, Seipel F, McCalla SG, Roy S, Ashton RS. Modular derivation of diverse, regionally discrete human posterior CNS neurons enables discovery of transcriptomic patterns. SCIENCE ADVANCES 2022; 8:eabn7430. [PMID: 36179024 PMCID: PMC9524835 DOI: 10.1126/sciadv.abn7430] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 08/16/2022] [Indexed: 06/02/2023]
Abstract
Our inability to derive the neuronal diversity that comprises the posterior central nervous system (pCNS) using human pluripotent stem cells (hPSCs) poses an impediment to understanding human neurodevelopment and disease in the hindbrain and spinal cord. Here, we establish a modular, monolayer differentiation paradigm that recapitulates both rostrocaudal (R/C) and dorsoventral (D/V) patterning, enabling derivation of diverse pCNS neurons with discrete regional specificity. First, neuromesodermal progenitors (NMPs) with discrete HOX profiles are converted to pCNS progenitors (pCNSPs). Then, by tuning D/V signaling, pCNSPs are directed to locomotor or somatosensory neurons. Expansive single-cell RNA-sequencing (scRNA-seq) analysis coupled with a novel computational pipeline allowed us to detect hundreds of transcriptional markers within region-specific phenotypes, enabling discovery of gene expression patterns across R/C and D/V developmental axes. These findings highlight the potential of these resources to advance a mechanistic understanding of pCNS development, enhance in vitro models, and inform therapeutic strategies.
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Affiliation(s)
- Nisha R. Iyer
- Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI, USA
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, USA
| | - Junha Shin
- Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI, USA
| | - Stephanie Cuskey
- Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI, USA
| | - Yucheng Tian
- Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI, USA
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, USA
| | - Noah R. Nicol
- Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI, USA
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, USA
| | - Tessa E. Doersch
- Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI, USA
| | - Frank Seipel
- Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI, USA
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, USA
| | - Sunnie Grace McCalla
- Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI, USA
- Department of Biostatistics and Medical Informatics, University of Wisconsin-Madison, Madison, WI, USA
| | - Sushmita Roy
- Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI, USA
- Department of Biostatistics and Medical Informatics, University of Wisconsin-Madison, Madison, WI, USA
| | - Randolph S. Ashton
- Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI, USA
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI, USA
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13
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Caplan IF, Hernandez-Morato I, Pitman MJ. Temporal expression of Laminin-111 in the developing rat larynx. Neurosci Lett 2022; 781:136658. [PMID: 35483501 PMCID: PMC9194551 DOI: 10.1016/j.neulet.2022.136658] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 04/08/2022] [Accepted: 04/22/2022] [Indexed: 12/31/2022]
Abstract
Laminin-111 is a basement membrane protein that participates in motor innervation and reinnervation. During axonal pathfinding, laminin-111 interacts with netrin-1 (NTN1) and changes its attractant growth cone properties into repulsion. While previous models of recurrent laryngeal nerve (RLN) transection show increased Laminin-111 and NTN1 production after injury, developmental expression in the larynx has not been defined. This study investigates the expression of laminin-111 in laryngeal muscles during primary laryngeal innervation of Sprague Dawley rats. Adult larynges and embryos were sectioned for immunohistochemistry with βIII-Tubulin, laminin subunit α-1 (LAMA1), NTN1, and α-bungarotoxin. Sections were processed for single-molecule inexpensive RNA fluorescence in situ hybridization analysis of LAMA1 mRNA. LAMA1 expression increased in all intrinsic laryngeal muscles, except the medial thyroarytenoid (MTA), at E20.5. At E20.5 there was increased expression in the lateral thyroarytenoid (LTA) and posterior cricoarytenoid (PCA) compared to the MTA. NTN1 upregulation was limited to the LTA and lateral cricoarytenoid (LCA) at E16.5 without any increase in the MTA or PCA. LAMA1 and NTN1 expression did not strictly follow expected patterns relative to the known timing of innervation and does not appear to be acting similarly to its role following RLN injury. These differences between developmental and post-injury innervation provide targets for investigations of therapeutics after nerve injury.
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Affiliation(s)
- Ian F. Caplan
- Columbia University Irving Medical Center/New York Presbyterian, Department of Otolaryngology Head & Neck Surgery, New York, NY, USA
| | - Ignacio Hernandez-Morato
- Columbia University Irving Medical Center/New York Presbyterian, Department of Otolaryngology Head & Neck Surgery, New York, NY, USA,Corresponding author at: Columbia University Irving Medical Center, Otolaryngology-Head and Neck Surgery, 180 Fort Washington Avenue, Rm 860 8th Floor. Harkness Pavilion, New York, NY 10032, USA. (I. Hernandez-Morato)
| | - Michael J. Pitman
- Columbia University Irving Medical Center/New York Presbyterian, Department of Otolaryngology Head & Neck Surgery, New York, NY, USA,Columbia University Irving Medical Center/New York Presbyterian, The Center for Voice and Swallowing, Department of Otolaryngology Head & Neck Surgery, New York, NY, USA
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14
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Moazeny M, Salari A, Hojati Z, Esmaeili F. Comparative analysis of protein-protein interaction networks in neural differentiation mechanisms. Differentiation 2022; 126:1-9. [DOI: 10.1016/j.diff.2022.05.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 05/05/2022] [Accepted: 05/11/2022] [Indexed: 11/03/2022]
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15
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To Stick or Not to Stick: Adhesions in Orofacial Clefts. BIOLOGY 2022; 11:biology11020153. [PMID: 35205020 PMCID: PMC8869391 DOI: 10.3390/biology11020153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Revised: 01/11/2022] [Accepted: 01/12/2022] [Indexed: 11/17/2022]
Abstract
Morphogenesis requires a tight coordination between mechanical forces and biochemical signals to inform individual cellular behavior. For these developmental processes to happen correctly the organism requires precise spatial and temporal coordination of the adhesion, migration, growth, differentiation, and apoptosis of cells originating from the three key embryonic layers, namely the ectoderm, mesoderm, and endoderm. The cytoskeleton and its remodeling are essential to organize and amplify many of the signaling pathways required for proper morphogenesis. In particular, the interaction of the cell junctions with the cytoskeleton functions to amplify the behavior of individual cells into collective events that are critical for development. In this review we summarize the key morphogenic events that occur during the formation of the face and the palate, as well as the protein complexes required for cell-to-cell adhesions. We then integrate the current knowledge into a comprehensive review of how mutations in cell-to-cell adhesion genes lead to abnormal craniofacial development, with a particular focus on cleft lip with or without cleft palate.
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16
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Hirsch D, Kohl A, Wang Y, Sela-Donenfeld D. Axonal Projection Patterns of the Dorsal Interneuron Populations in the Embryonic Hindbrain. Front Neuroanat 2022; 15:793161. [PMID: 35002640 PMCID: PMC8738170 DOI: 10.3389/fnana.2021.793161] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 11/29/2021] [Indexed: 12/12/2022] Open
Abstract
Unraveling the inner workings of neural circuits entails understanding the cellular origin and axonal pathfinding of various neuronal groups during development. In the embryonic hindbrain, different subtypes of dorsal interneurons (dINs) evolve along the dorsal-ventral (DV) axis of rhombomeres and are imperative for the assembly of central brainstem circuits. dINs are divided into two classes, class A and class B, each containing four neuronal subgroups (dA1-4 and dB1-4) that are born in well-defined DV positions. While all interneurons belonging to class A express the transcription factor Olig3 and become excitatory, all class B interneurons express the transcription factor Lbx1 but are diverse in their excitatory or inhibitory fate. Moreover, within every class, each interneuron subtype displays its own specification genes and axonal projection patterns which are required to govern the stage-by-stage assembly of their connectivity toward their target sites. Remarkably, despite the similar genetic landmark of each dINs subgroup along the anterior-posterior (AP) axis of the hindbrain, genetic fate maps of some dA/dB neuronal subtypes uncovered their contribution to different nuclei centers in relation to their rhombomeric origin. Thus, DV and AP positional information has to be orchestrated in each dA/dB subpopulation to form distinct neuronal circuits in the hindbrain. Over the span of several decades, different axonal routes have been well-documented to dynamically emerge and grow throughout the hindbrain DV and AP positions. Yet, the genetic link between these distinct axonal bundles and their neuronal origin is not fully clear. In this study, we reviewed the available data regarding the association between the specification of early-born dorsal interneuron subpopulations in the hindbrain and their axonal circuitry development and fate, as well as the present existing knowledge on molecular effectors underlying the process of axonal growth.
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Affiliation(s)
- Dana Hirsch
- Koret School of Veterinary Medicine, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel.,Department of Veterinary Resources, Weizmann Institute of Science, Rehovot, Israel
| | - Ayelet Kohl
- Koret School of Veterinary Medicine, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Yuan Wang
- Department of Biomedical Sciences, Program in Neuroscience, College of Medicine, Florida State University, Tallahassee, FL, United States
| | - Dalit Sela-Donenfeld
- Koret School of Veterinary Medicine, The Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot, Israel
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17
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Kamitakahara AK, Ali Marandi Ghoddousi R, Lanjewar AL, Magalong VM, Wu HH, Levitt P. MET Receptor Tyrosine Kinase Regulates Lifespan Ultrasonic Vocalization and Vagal Motor Neuron Development. Front Neurosci 2021; 15:768577. [PMID: 34803597 PMCID: PMC8600253 DOI: 10.3389/fnins.2021.768577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 10/14/2021] [Indexed: 11/25/2022] Open
Abstract
The intrinsic muscles of the larynx are innervated by the vagal motor nucleus ambiguus (nAmb), which provides direct motor control over vocal production in humans and rodents. Here, we demonstrate in mice using the Phox2b Cre line, that conditional embryonic deletion of the gene encoding the MET receptor tyrosine kinase (MET) in the developing brainstem (cKO) results in highly penetrant, severe deficits in ultrasonic vocalization in early postnatal life. Major deficits and abnormal vocalization patterns persist into adulthood in more than 70% of mice, with the remaining recovering the ability to vocalize, reflecting heterogeneity in circuit restitution. We show that underlying the functional deficits, conditional deletion of Met results in a loss of approximately one-third of MET+ nAmb motor neurons, which begins as early as embryonic day 14.5. The loss of motor neurons is specific to the nAmb, as other brainstem motor and sensory nuclei are unaffected. In the recurrent laryngeal nerve, through which nAmb motor neurons project to innervate the larynx, there is a one-third loss of axons in cKO mice. Together, the data reveal a novel, heterogenous MET-dependence, for which MET differentially affects survival of a subset of nAmb motor neurons necessary for lifespan ultrasonic vocal capacity.
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Affiliation(s)
- Anna K. Kamitakahara
- Program in Developmental Neuroscience and Neurogenetics, Children’s Hospital Los Angeles, The Saban Research Institute, Los Angeles, CA, United States
- Department of Pediatrics, Keck School of Medicine of University of Southern California, Los Angeles, CA, United States
| | - Ramin Ali Marandi Ghoddousi
- Program in Developmental Neuroscience and Neurogenetics, Children’s Hospital Los Angeles, The Saban Research Institute, Los Angeles, CA, United States
- Department of Pediatrics, Keck School of Medicine of University of Southern California, Los Angeles, CA, United States
- Neuroscience Graduate Program, University of Southern California, Los Angeles, CA, United States
| | - Alexandra L. Lanjewar
- Program in Developmental Neuroscience and Neurogenetics, Children’s Hospital Los Angeles, The Saban Research Institute, Los Angeles, CA, United States
- Department of Pediatrics, Keck School of Medicine of University of Southern California, Los Angeles, CA, United States
- Neuroscience Graduate Program, University of Southern California, Los Angeles, CA, United States
| | - Valerie M. Magalong
- Program in Developmental Neuroscience and Neurogenetics, Children’s Hospital Los Angeles, The Saban Research Institute, Los Angeles, CA, United States
- Department of Pediatrics, Keck School of Medicine of University of Southern California, Los Angeles, CA, United States
| | - Hsiao-Huei Wu
- Department of Pediatrics, Keck School of Medicine of University of Southern California, Los Angeles, CA, United States
| | - Pat Levitt
- Program in Developmental Neuroscience and Neurogenetics, Children’s Hospital Los Angeles, The Saban Research Institute, Los Angeles, CA, United States
- Department of Pediatrics, Keck School of Medicine of University of Southern California, Los Angeles, CA, United States
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18
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Motahari Z, Maynard TM, Popratiloff A, Moody SA, LaMantia AS. Aberrant early growth of individual trigeminal sensory and motor axons in a series of mouse genetic models of 22q11.2 deletion syndrome. Hum Mol Genet 2021; 29:3081-3093. [PMID: 32901287 PMCID: PMC7645708 DOI: 10.1093/hmg/ddaa199] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 07/29/2020] [Accepted: 09/01/2020] [Indexed: 02/06/2023] Open
Abstract
We identified divergent modes of initial axon growth that prefigure disrupted differentiation of the trigeminal nerve (CN V), a cranial nerve essential for suckling, feeding and swallowing (S/F/S), a key innate behavior compromised in multiple genetic developmental disorders including DiGeorge/22q11.2 Deletion Syndrome (22q11.2 DS). We combined rapid in vivo labeling of single CN V axons in LgDel+/− mouse embryos, a genomically accurate 22q11.2DS model, and 3D imaging to identify and quantify phenotypes that could not be resolved using existing methods. We assessed these phenotypes in three 22q11.2-related genotypes to determine whether individual CN V motor and sensory axons wander, branch and sprout aberrantly in register with altered anterior–posterior hindbrain patterning and gross morphological disruption of CN V seen in LgDel+/−. In the additional 22q11.2-related genotypes: Tbx1+/−, Ranbp1−/−, Ranbp1+/− and LgDel+/−:Raldh2+/−; axon phenotypes are seen when hindbrain patterning and CN V gross morphology is altered, but not when it is normal or restored toward WT. This disordered growth of CN V sensory and motor axons, whose appropriate targeting is critical for optimal S/F/S, may be an early, critical determinant of imprecise innervation leading to inefficient oropharyngeal function associated with 22q11.2 deletion from birth onward.
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Affiliation(s)
- Zahra Motahari
- Institute for Neuroscience, Washington, DC 20037, USA.,Department of Anatomy and Cell Biology, The George Washington University School of Medicine and Health Sciences, Washington, DC 20037, USA
| | - Thomas M Maynard
- The Fralin Biomedical Research Institute at Virginia Tech-Carilion School of Medicine, Roanoke, VA 24016, USA
| | - Anastas Popratiloff
- Institute for Neuroscience, Washington, DC 20037, USA.,Department of Anatomy and Cell Biology, The George Washington University School of Medicine and Health Sciences, Washington, DC 20037, USA
| | - Sally A Moody
- Institute for Neuroscience, Washington, DC 20037, USA.,Department of Anatomy and Cell Biology, The George Washington University School of Medicine and Health Sciences, Washington, DC 20037, USA
| | - Anthony-S LaMantia
- The Fralin Biomedical Research Institute at Virginia Tech-Carilion School of Medicine, Roanoke, VA 24016, USA.,Department of Biological Sciences, Virginia Tech, Blacksburg, VA 24060, USA
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19
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Asante E, Hummel D, Gurung S, Kassim YM, Al-Shakarji N, Palaniappan K, Sittaramane V, Chandrasekhar A. Defective Neuronal Positioning Correlates With Aberrant Motor Circuit Function in Zebrafish. Front Neural Circuits 2021; 15:690475. [PMID: 34248505 PMCID: PMC8265374 DOI: 10.3389/fncir.2021.690475] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 06/01/2021] [Indexed: 11/18/2022] Open
Abstract
Precise positioning of neurons resulting from cell division and migration during development is critical for normal brain function. Disruption of neuronal migration can cause a myriad of neurological disorders. To investigate the functional consequences of defective neuronal positioning on circuit function, we studied a zebrafish frizzled3a (fzd3a) loss-of-function mutant off-limits (olt) where the facial branchiomotor (FBM) neurons fail to migrate out of their birthplace. A jaw movement assay, which measures the opening of the zebrafish jaw (gape), showed that the frequency of gape events, but not their amplitude, was decreased in olt mutants. Consistent with this, a larval feeding assay revealed decreased food intake in olt mutants, indicating that the FBM circuit in mutants generates defective functional outputs. We tested various mechanisms that could generate defective functional outputs in mutants. While fzd3a is ubiquitously expressed in neural and non-neural tissues, jaw cartilage and muscle developed normally in olt mutants, and muscle function also appeared to be unaffected. Although FBM neurons were mispositioned in olt mutants, axon pathfinding to jaw muscles was unaffected. Moreover, neuromuscular junctions established by FBM neurons on jaw muscles were similar between wildtype siblings and olt mutants. Interestingly, motor axons innervating the interhyoideus jaw muscle were frequently defasciculated in olt mutants. Furthermore, GCaMP imaging revealed that mutant FBM neurons were less active than their wildtype counterparts. These data show that aberrant positioning of FBM neurons in olt mutants is correlated with subtle defects in fasciculation and neuronal activity, potentially generating defective functional outputs.
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Affiliation(s)
- Emilia Asante
- Division of Biological Sciences and Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
| | - Devynn Hummel
- Division of Biological Sciences and Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
| | - Suman Gurung
- Division of Biological Sciences and Bond Life Sciences Center, University of Missouri, Columbia, MO, United States.,Department of Pathology and Cell Biology, USF Health Heart Institute, University of South Florida, Tampa, Florida, FL, United States
| | - Yasmin M Kassim
- Computational Imaging and VisAnalysis (CIVA) Lab, Department of Electrical Engineering and Computer Science, University of Missouri, Columbia, MO, United States
| | - Noor Al-Shakarji
- Computational Imaging and VisAnalysis (CIVA) Lab, Department of Electrical Engineering and Computer Science, University of Missouri, Columbia, MO, United States
| | - Kannappan Palaniappan
- Computational Imaging and VisAnalysis (CIVA) Lab, Department of Electrical Engineering and Computer Science, University of Missouri, Columbia, MO, United States
| | - Vinoth Sittaramane
- Department of Biology, Georgia Southern University, Statesboro, GA, United States
| | - Anand Chandrasekhar
- Division of Biological Sciences and Bond Life Sciences Center, University of Missouri, Columbia, MO, United States
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20
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Jahan I, Kersigo J, Elliott KL, Fritzsch B. Smoothened overexpression causes trochlear motoneurons to reroute and innervate ipsilateral eyes. Cell Tissue Res 2021; 384:59-72. [PMID: 33409653 DOI: 10.1007/s00441-020-03352-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 11/16/2020] [Indexed: 12/22/2022]
Abstract
The trochlear projection is unique among the cranial nerves in that it exits the midbrain dorsally to innervate the contralateral superior oblique muscle in all vertebrates. Trochlear as well as oculomotor motoneurons uniquely depend upon Phox2a and Wnt1, both of which are downstream of Lmx1b, though why trochlear motoneurons display such unusual projections is not fully known. We used Pax2-cre to drive expression of ectopically activated Smoothened (SmoM2) dorsally in the midbrain and anterior hindbrain. We documented the expansion of oculomotor and trochlear motoneurons using Phox2a as a specific marker at E9.5. We show that the initial expansion follows a demise of these neurons by E14.5. Furthermore, SmoM2 expression leads to a ventral exit and ipsilateral projection of trochlear motoneurons. We compare that data with Unc5c mutants that shows a variable ipsilateral number of trochlear fibers that exit dorsal. Our data suggest that Shh signaling is involved in trochlear motoneuron projections and that the deflected trochlear projections after SmoM2 expression is likely due to the dorsal expression of Gli1, which impedes the normal dorsal trajectory of these neurons.
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Affiliation(s)
- Israt Jahan
- Department of Biology, University of Iowa, Iowa City, IA, 52242, USA
| | - Jennifer Kersigo
- Department of Biology, University of Iowa, Iowa City, IA, 52242, USA
| | - Karen L Elliott
- Department of Biology, University of Iowa, Iowa City, IA, 52242, USA
| | - Bernd Fritzsch
- Department of Biology, University of Iowa, Iowa City, IA, 52242, USA. .,Department of Otolaryngology, University of Iowa, Iowa City, IA, 52242, USA.
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21
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Liu W, Fu W, Sun M, Han K, Hu R, Liu D, Wang J. Straightforward neuron micropatterning and neuronal network construction on cell-repellent polydimethylsiloxane using microfluidics-guided functionalized Pluronic modification. Analyst 2021; 146:454-462. [PMID: 33491017 DOI: 10.1039/d0an02139c] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Neuronal cell microengineering involving micropatterning and polydimethylsiloxane (PDMS) microfluidics enables promising advances in microscale neuron control. However, a facile methodology for the precise and effective manipulation of neurons on a cell-repellent PDMS substrate remains challenging. Herein, a simple and straightforward strategy for neuronal cell patterning and neuronal network construction on PDMS based on microfluidics-assisted modification of functionalized Pluronic is described. The cell patterning process simply involves a one-step microfluidic modification and routine in vitro culture. It is demonstrated that multiple types of neuronal cell arrangements with various spatial profiles can be conveniently produced using this patterning tool. The precise control of neuronal cells with high patterning fidelity up to single cell resolution, as well as high adhesion and differentiation, is achieved too. Furthermore, neuronal network construction using the respective cell population and single cell patterning prove to be applicable. This achievement provides a convenient and feasible methodology for engineering neuronal cells on PDMS substrates, which will be useful for applications in many neuron-related microscale analytical research fields, including cell engineering, neurobiology, neuropharmacology, and neuronal sensing.
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Affiliation(s)
- Wenming Liu
- Departments of Biomedical Engineering and Pathology, School of Basic Medical Science, Central South University, Changsha, Hunan 410013, China.
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22
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Andersen J, Revah O, Miura Y, Thom N, Amin ND, Kelley KW, Singh M, Chen X, Thete MV, Walczak EM, Vogel H, Fan HC, Paşca SP. Generation of Functional Human 3D Cortico-Motor Assembloids. Cell 2020; 183:1913-1929.e26. [PMID: 33333020 DOI: 10.1016/j.cell.2020.11.017] [Citation(s) in RCA: 227] [Impact Index Per Article: 56.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 05/27/2020] [Accepted: 11/04/2020] [Indexed: 12/21/2022]
Abstract
Neurons in the cerebral cortex connect through descending pathways to hindbrain and spinal cord to activate muscle and generate movement. Although components of this pathway have been previously generated and studied in vitro, the assembly of this multi-synaptic circuit has not yet been achieved with human cells. Here, we derive organoids resembling the cerebral cortex or the hindbrain/spinal cord and assemble them with human skeletal muscle spheroids to generate 3D cortico-motor assembloids. Using rabies tracing, calcium imaging, and patch-clamp recordings, we show that corticofugal neurons project and connect with spinal spheroids, while spinal-derived motor neurons connect with muscle. Glutamate uncaging or optogenetic stimulation of cortical spheroids triggers robust contraction of 3D muscle, and assembloids are morphologically and functionally intact for up to 10 weeks post-fusion. Together, this system highlights the remarkable self-assembly capacity of 3D cultures to form functional circuits that could be used to understand development and disease.
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Affiliation(s)
- Jimena Andersen
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA; Stanford Brain Organogenesis Program, Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA 94305, USA
| | - Omer Revah
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA; Stanford Brain Organogenesis Program, Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA 94305, USA
| | - Yuki Miura
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA; Stanford Brain Organogenesis Program, Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA 94305, USA
| | - Nicholas Thom
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA
| | - Neal D Amin
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA; Stanford Brain Organogenesis Program, Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA 94305, USA
| | - Kevin W Kelley
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA; Stanford Brain Organogenesis Program, Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA 94305, USA
| | - Mandeep Singh
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA; Stanford Brain Organogenesis Program, Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA 94305, USA
| | - Xiaoyu Chen
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA; Stanford Brain Organogenesis Program, Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA 94305, USA
| | - Mayuri Vijay Thete
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA
| | | | - Hannes Vogel
- Departments of Pathology and Pediatrics, Stanford University, Stanford, CA 94305, USA
| | - H Christina Fan
- BD Biosciences, 4040 Campbell Ave Suite 110, Menlo Park, CA 94025, USA
| | - Sergiu P Paşca
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA; Stanford Brain Organogenesis Program, Wu Tsai Neurosciences Institute, Stanford University, Stanford, CA 94305, USA.
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23
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Pimentel HDC, Macêdo-Lima M, Viola GG, Melleu FF, Dos Santos TS, Franco HS, da Silva RDS, Lino-de-Oliveira C, Marino-Neto J, Dos Santos JR, Marchioro M. Telencephalic distributions of doublecortin and glial fibrillary acidic protein suggest novel migratory pathways in adult lizards. J Chem Neuroanat 2020; 112:101901. [PMID: 33271217 DOI: 10.1016/j.jchemneu.2020.101901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 11/26/2020] [Accepted: 11/26/2020] [Indexed: 11/30/2022]
Abstract
Adult neurogenesis has been reported in all major vertebrate taxa. However, neurogenic rates and the number of neurogenic foci vary greatly, and are higher in ancestral taxa. Our study aimed to evaluate the distribution of doublecortin (DCX) and glial fibrillary acidic protein (GFAP) in telencephalic areas of the adult tropical lizard Tropidurus hispidus. We describe evidence for four main neurogenic foci, which coincide anatomically with the ventricular sulci described by the literature. Based on neuronal morphology, we infer four migratory patterns/pathways. In the cortex, patterns of GFAP and DCX staining support radial migrations from ventricular zones into cortical areas and dorsoventricular ridge. Cells radiating from the sulcus septomedialis (SM) seemed to migrate to the medial cortex and dorsal cortex. From the sulcus lateralis (SL), they seemed to be bound for the lateral cortex, central amygdala and nucleus sphericus. We describe a DCX-positive stream originating in the caudal sulcus ventralis and seemingly bound for the olfactory bulb, resembling a rostral migratory stream. We provide evidence for a previously undescribed tangential dorso-septo-caudal migratory stream, with neuroblasts supported by DCX-positive fibers. Finally, we provide evidence for a commissural migration stream seemingly bound for the contralateral nucleus sphericus. Therefore, in addition to two previously known migratory streams, this study provides anatomical evidence in support for two novel migratory routes in amniotes.
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Affiliation(s)
- Hugo de C Pimentel
- Laboratory of Neurophysiology, Department of Physiology, Federal University of Sergipe, São Cristovão, SE, Brazil
| | - Matheus Macêdo-Lima
- Center for Neuroendocrine Studies, University of Massachusetts Amherst, Amherst, MA, USA
| | - Giordano G Viola
- Laboratory of Neurophysiology, Department of Physiology, Federal University of Sergipe, São Cristovão, SE, Brazil
| | - Fernando F Melleu
- Department of Physiological Sciences, Federal University of Santa Catarina, SC, Brazil
| | - Tiago S Dos Santos
- Department of Physiological Sciences, Federal University of Santa Catarina, SC, Brazil
| | - Heitor S Franco
- Laboratory of Behavioral and Evolutionary Neurobiology, Department of Biosciences, Federal University of Sergipe, Itabaiana, SE, Brazil
| | - Rodolfo Dos S da Silva
- Laboratory of Behavioral and Evolutionary Neurobiology, Department of Biosciences, Federal University of Sergipe, Itabaiana, SE, Brazil
| | | | - José Marino-Neto
- Department of Physiological Sciences, Federal University of Santa Catarina, SC, Brazil
| | - José R Dos Santos
- Laboratory of Behavioral and Evolutionary Neurobiology, Department of Biosciences, Federal University of Sergipe, Itabaiana, SE, Brazil.
| | - Murilo Marchioro
- Laboratory of Neurophysiology, Department of Physiology, Federal University of Sergipe, São Cristovão, SE, Brazil.
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24
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Pujades C. The multiple functions of hindbrain boundary cells: Tinkering boundaries? Semin Cell Dev Biol 2020; 107:179-189. [DOI: 10.1016/j.semcdb.2020.05.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 04/29/2020] [Accepted: 05/02/2020] [Indexed: 02/01/2023]
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25
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Vermeiren S, Bellefroid EJ, Desiderio S. Vertebrate Sensory Ganglia: Common and Divergent Features of the Transcriptional Programs Generating Their Functional Specialization. Front Cell Dev Biol 2020; 8:587699. [PMID: 33195244 PMCID: PMC7649826 DOI: 10.3389/fcell.2020.587699] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 09/08/2020] [Indexed: 12/13/2022] Open
Abstract
Sensory fibers of the peripheral nervous system carry sensation from specific sense structures or use different tissues and organs as receptive fields, and convey this information to the central nervous system. In the head of vertebrates, each cranial sensory ganglia and associated nerves perform specific functions. Sensory ganglia are composed of different types of specialized neurons in which two broad categories can be distinguished, somatosensory neurons relaying all sensations that are felt and visceral sensory neurons sensing the internal milieu and controlling body homeostasis. While in the trunk somatosensory neurons composing the dorsal root ganglia are derived exclusively from neural crest cells, somato- and visceral sensory neurons of cranial sensory ganglia have a dual origin, with contributions from both neural crest and placodes. As most studies on sensory neurogenesis have focused on dorsal root ganglia, our understanding of the molecular mechanisms underlying the embryonic development of the different cranial sensory ganglia remains today rudimentary. However, using single-cell RNA sequencing, recent studies have made significant advances in the characterization of the neuronal diversity of most sensory ganglia. Here we summarize the general anatomy, function and neuronal diversity of cranial sensory ganglia. We then provide an overview of our current knowledge of the transcriptional networks controlling neurogenesis and neuronal diversification in the developing sensory system, focusing on cranial sensory ganglia, highlighting specific aspects of their development and comparing it to that of trunk sensory ganglia.
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Affiliation(s)
- Simon Vermeiren
- ULB Neuroscience Institute, Université Libre de Bruxelles, Gosselies, Belgium
| | - Eric J Bellefroid
- ULB Neuroscience Institute, Université Libre de Bruxelles, Gosselies, Belgium
| | - Simon Desiderio
- Institute for Neurosciences of Montpellier, INSERM U1051, University of Montpellier, Montpellier, France
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26
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Abstract
Neuronal circuits that regulate movement are distributed throughout the nervous system. The brainstem is an important interface between upper motor centers involved in action planning and circuits in the spinal cord ultimately leading to execution of body movements. Here we focus on recent work using genetic and viral entry points to reveal the identity of functionally dedicated and frequently spatially intermingled brainstem populations essential for action diversification, a general principle conserved throughout evolution. Brainstem circuits with distinct organization and function control skilled forelimb behavior, orofacial movements, and locomotion. They convey regulatory parameters to motor output structures and collaborate in the construction of complex natural motor behaviors. Functionally tuned brainstem neurons for different actions serve as important integrators of synaptic inputs from upstream centers, including the basal ganglia and cortex, to regulate and modulate behavioral function in different contexts.
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Affiliation(s)
- Ludwig Ruder
- Biozentrum, Department of Cell Biology, University of Basel, 4056 Basel, Switzerland; .,Friedrich Miescher Institute for Biomedical Research, 4058 Basel, Switzerland
| | - Silvia Arber
- Biozentrum, Department of Cell Biology, University of Basel, 4056 Basel, Switzerland; .,Friedrich Miescher Institute for Biomedical Research, 4058 Basel, Switzerland
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27
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Brown S, Yuan Y, Belyk M. Evolution of the speech-ready brain: The voice/jaw connection in the human motor cortex. J Comp Neurol 2020; 529:1018-1028. [PMID: 32720701 DOI: 10.1002/cne.24997] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Revised: 07/07/2020] [Accepted: 07/19/2020] [Indexed: 12/18/2022]
Abstract
A prominent model of the origins of speech, known as the "frame/content" theory, posits that oscillatory lowering and raising of the jaw provided an evolutionary scaffold for the development of syllable structure in speech. Because such oscillations are nonvocal in most nonhuman primates, the evolution of speech required the addition of vocalization onto this scaffold in order to turn such jaw oscillations into vocalized syllables. In the present functional MRI study, we demonstrate overlapping somatotopic representations between the larynx and the jaw muscles in the human primary motor cortex. This proximity between the larynx and jaw in the brain might support the coupling between vocalization and jaw oscillations to generate syllable structure. This model suggests that humans inherited voluntary control of jaw oscillations from ancestral species, but added voluntary control of vocalization onto this via the evolution of a new brain area that came to be situated near the jaw region in the human motor cortex.
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Affiliation(s)
- Steven Brown
- Department of Psychology, Neuroscience & Behaviour, McMaster University, Hamilton, Ontario, Canada
| | - Ye Yuan
- Department of Psychology, Neuroscience & Behaviour, McMaster University, Hamilton, Ontario, Canada
| | - Michel Belyk
- Department of Speech Hearing and Phonetic Sciences, University College London, London, UK
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28
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Protocadherin-Mediated Cell Repulsion Controls the Central Topography and Efferent Projections of the Abducens Nucleus. Cell Rep 2020; 24:1562-1572. [PMID: 30089266 DOI: 10.1016/j.celrep.2018.07.024] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 05/31/2018] [Accepted: 07/06/2018] [Indexed: 11/21/2022] Open
Abstract
Cranial motor nuclei in the brainstem innervate diverse types of head and neck muscles. Failure in establishing these neuromuscular connections causes congenital cranial dysinnervation disorders (CCDDs) characterized by abnormal craniofacial movements. However, mechanisms that link cranial motor nuclei to target muscles are poorly understood at the molecular level. Here, we report that protocadherin-mediated repulsion mediates neuromuscular connection in the ocular motor system in zebrafish. We identify pools of abducens motor neurons that are topographically arranged according to soma size and convergently innervate a single muscle. Disruptions of Duane retraction syndrome-associated transcription factors reveal that these neurons require Mafba/MAFB, but not Sall4/SALL4, for differentiation. Furthermore, genetic perturbations of Pcdh17/protocadherin-17 result in defective axon growth and soma clumping, thereby abolishing neuromuscular connectivity. Our results suggest that protocadherin-mediated repulsion forms the central topography and efferent projection pattern of the abducens nucleus following Mafba-dependent specification and imply potential involvement of protocadherins in CCDD etiology.
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29
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Li L, Pu Q, Hintze M, Wang Y, Eckhardt M, Gieselmann V, Tiemann I, Qi X, Cai D, Wang J, Huang R. BDNF and NGF signals originating from sensory ganglia promote cranial motor axon growth. Exp Brain Res 2019; 238:111-119. [PMID: 31802149 DOI: 10.1007/s00221-019-05694-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 11/15/2019] [Indexed: 11/29/2022]
Abstract
After exiting the hindbrain, branchial motor axons reach their targets in association with sensory ganglia. The trigeminal ganglion has been shown to promote motor axon growth from rhombomeres 2/3 and 4/5, but it is unknown whether this effect is ganglion specific and through which signals it is mediated. Here, we addressed these questions by co-cultures of ventral rhombomere 8 explants with cranial and spinal sensory ganglia in a collagen gel matrix. Our results show that all cranial sensory ganglia and even a trunk dorsal root ganglion can promote motor axon growth and that ganglia isolated from older embryos had a stronger effect on the axonal growth than younger ones. We found that brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) are necessary and sufficient for this effect. Altogether, our results demonstrate that the promoting effect of sensory ganglia on cranial motor axon growth is stage dependent, but not ganglion specific and is mediated by BDNF and NGF signals.
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Affiliation(s)
- Lianlian Li
- Department of Neuroanatomy, Institute of Anatomy, University of Bonn, Nussallee 10, 53115, Bonn, Germany.,Institute of Zoology, School of Life Science, Lanzhou University, Lanzhou, China.,Institute of Basic Medicine, Shandong Academy of Medical Sciences, Jinan, China
| | - Qin Pu
- Department of Neuroanatomy, Institute of Anatomy, University of Bonn, Nussallee 10, 53115, Bonn, Germany
| | - Maik Hintze
- Department of Neuroanatomy, Institute of Anatomy, University of Bonn, Nussallee 10, 53115, Bonn, Germany
| | - Yong Wang
- Institute of Biochemistry and Molecular Biology, University of Bonn, Bonn, Germany
| | - Matthias Eckhardt
- Institute of Biochemistry and Molecular Biology, University of Bonn, Bonn, Germany
| | - Volkmar Gieselmann
- Institute of Biochemistry and Molecular Biology, University of Bonn, Bonn, Germany
| | - Inga Tiemann
- Institute of Animal Science, University of Bonn, Bonn, Germany
| | - Xufeng Qi
- Key Laboratory of Regenerative Medicine, Ministry of Education, Jinan University, Guangzhou, China
| | - Dongqing Cai
- Key Laboratory of Regenerative Medicine, Ministry of Education, Jinan University, Guangzhou, China
| | - Jianlin Wang
- Institute of Zoology, School of Life Science, Lanzhou University, Lanzhou, China
| | - Ruijin Huang
- Department of Neuroanatomy, Institute of Anatomy, University of Bonn, Nussallee 10, 53115, Bonn, Germany. .,Department of Molecular Embryology, Institute of Anatomy and Cell Biology, University of Freiburg, Freiburg im Breisgau, Germany.
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30
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Wealing JC, Cholanian M, Flanigan EG, Levine RB, Fregosi RF. Diverse physiological properties of hypoglossal motoneurons innervating intrinsic and extrinsic tongue muscles. J Neurophysiol 2019; 122:2054-2060. [PMID: 31533009 PMCID: PMC6879950 DOI: 10.1152/jn.00478.2019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 09/05/2019] [Accepted: 09/13/2019] [Indexed: 12/16/2022] Open
Abstract
The mammalian tongue contains eight muscles that collaborate to ensure that suckling, swallowing, and other critical functions are robust and reliable. Seven of the eight tongue muscles are innervated by hypoglossal motoneurons (XIIMNs). A somatotopic organization of the XII motor nucleus, defined in part by the mechanical action of a neuron's target muscle, has been described, but whether or not XIIMNs within a compartment are functionally specialized is unsettled. We hypothesize that developing XIIMNs are assigned unique functional properties that reflect the challenges that their target muscle faces upon the transition from in utero to terrestrial life. To address this, we studied XIIMNs that innervate intrinsic and extrinsic tongue muscles, because intrinsic muscles play a more prominent role in suckling than the extrinsic muscles. We injected dextran-rhodamine into the intrinsic longitudinal muscles (IL) and the extrinsic genioglossus, and physiologically characterized the labeled XIIMNs. Consistent with earlier work, IL XIIMNs (n = 150) were located more dorsally within the nucleus, and GG XIIMNs (n = 55) more ventrally. Whole cell recordings showed that resting membrane potential was, on average, 9 mV more depolarized in IL than in GG XIIMNs (P = 0.0019), and the firing threshold in response to current injection was lower in IL (-31 ± 23 pA) than in GG XIIMNs (225 ± 39 pA; P < 0.0001). We also found that the appearance of net outward currents in GG XIIMNs occurred at more hyperpolarized membrane potentials than IL XIIMNs, consistent with lower excitability in GG XIIMNs. These observations document muscle-specific functional specializations among XIIMNs.NEW & NOTEWORTHY The hypoglossal motor nucleus contains motoneurons responsible for innervating one of seven different muscles with notably different biomechanics and patterns of use. Whether or not motoneurons innervating the different muscles also have unique functional properties (e.g., spiking behavior, synaptic physiology) is poorly understood. In this work we show that neonatal hypoglossal motoneurons innervating muscles that shape the tongue (intrinsic longitudinal muscles) have different electrical properties than those innervating the genioglossus, which controls tongue position.
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Affiliation(s)
- J. C. Wealing
- Department of Physiology, The University of Arizona, Tucson, Arizona
| | - M. Cholanian
- Department of Physiology, The University of Arizona, Tucson, Arizona
| | - E. G. Flanigan
- Department of Physiology, The University of Arizona, Tucson, Arizona
| | - R. B. Levine
- Department of Physiology, The University of Arizona, Tucson, Arizona
- Department of Neuroscience, The University of Arizona, Tucson, Arizona
| | - R. F. Fregosi
- Department of Physiology, The University of Arizona, Tucson, Arizona
- Department of Neuroscience, The University of Arizona, Tucson, Arizona
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31
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Ashikawa Y, Shiromizu T, Miura K, Adachi Y, Matsui T, Bessho Y, Tanaka T, Nishimura Y. C3orf70 Is Involved in Neural and Neurobehavioral Development. Pharmaceuticals (Basel) 2019; 12:ph12040156. [PMID: 31623237 PMCID: PMC6958487 DOI: 10.3390/ph12040156] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 10/15/2019] [Indexed: 12/29/2022] Open
Abstract
Neurogenesis is the process by which undifferentiated progenitor cells develop into mature and functional neurons. Defects in neurogenesis are associated with neurodevelopmental and neuropsychiatric disorders; therefore, elucidating the molecular mechanisms underlying neurogenesis can advance our understanding of the pathophysiology of these disorders and facilitate the discovery of novel therapeutic targets. In this study, we performed a comparative transcriptomic analysis to identify common targets of the proneural transcription factors Neurog1/2 and Ascl1 during neurogenesis of human and mouse stem cells. We successfully identified C3orf70 as a novel common target gene of Neurog1/2 and Ascl1 during neurogenesis. Using in situ hybridization, we demonstrated that c3orf70a and c3orf70b, two orthologs of C3orf70, were expressed in the midbrain and hindbrain of zebrafish larvae. We generated c3orf70 knockout zebrafish using CRISPR/Cas9 technology and demonstrated that loss of c3orf70 resulted in significantly decreased expression of the mature neuron markers elavl3 and eno2. We also found that expression of irx3b, a zebrafish ortholog of IRX3 and a midbrain/hindbrain marker, was significantly reduced in c3orf70 knockout zebrafish. Finally, we demonstrated that neurobehaviors related to circadian rhythm and altered light–dark conditions were significantly impaired in c3orf70 knockout zebrafish. These results suggest that C3orf70 is involved in neural and neurobehavioral development and that defects in C3orf70 may be associated with midbrain/hindbrain-related neurodevelopmental and neuropsychiatric disorders.
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Affiliation(s)
- Yoshifumi Ashikawa
- Department of Integrative Pharmacology, Mie University Graduate School of Medicine, Tsu, Mie 514-8507, Japan; (Y.A.); (T.S.); (K.M.); (Y.A.)
| | - Takashi Shiromizu
- Department of Integrative Pharmacology, Mie University Graduate School of Medicine, Tsu, Mie 514-8507, Japan; (Y.A.); (T.S.); (K.M.); (Y.A.)
| | - Koki Miura
- Department of Integrative Pharmacology, Mie University Graduate School of Medicine, Tsu, Mie 514-8507, Japan; (Y.A.); (T.S.); (K.M.); (Y.A.)
| | - Yuka Adachi
- Department of Integrative Pharmacology, Mie University Graduate School of Medicine, Tsu, Mie 514-8507, Japan; (Y.A.); (T.S.); (K.M.); (Y.A.)
| | - Takaaki Matsui
- Gene Regulation Research, Graduate School of Biological Sciences, Nara Institute of Science and Technology, Takayama, Nara 630-0192, Japan; (T.M.); (Y.B.)
| | - Yasumasa Bessho
- Gene Regulation Research, Graduate School of Biological Sciences, Nara Institute of Science and Technology, Takayama, Nara 630-0192, Japan; (T.M.); (Y.B.)
| | - Toshio Tanaka
- Department of Systems Pharmacology, Mie University Graduate School of Medicine, Tsu, Mie 514-8507, Japan;
| | - Yuhei Nishimura
- Department of Integrative Pharmacology, Mie University Graduate School of Medicine, Tsu, Mie 514-8507, Japan; (Y.A.); (T.S.); (K.M.); (Y.A.)
- Correspondence:
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32
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Haładaj R, Wysiadecki G, Tubbs RS. Intramuscular innervation of the lateral rectus muscle evaluated using sihler's staining technique: Potential application to strabismus surgery. Clin Anat 2019; 33:585-591. [PMID: 31429984 DOI: 10.1002/ca.23452] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2019] [Revised: 08/15/2019] [Accepted: 08/15/2019] [Indexed: 12/20/2022]
Abstract
The latest research suggests that the abducens nerve may be divided into subbranches that reach functionally distinct zones of the lateral rectus muscle. The goal of the study was to examine this muscle's innervation, including the detailed distribution of the intramuscular subbranches of the abducens nerve. Twenty-five lateral rectus muscle specimens were harvested (with the orbital segment of the abducens nerve), fixed in 10% formalin solution, and stained with Sihler's whole mount nerve staining technique. Subbranches running to the lateral rectus divided into two main groups: superior and inferior. Both groups of subbranches are distributed in a fan-shaped manner, show a characteristic "tree-like" branching pattern and form terminal plexus near the proximal half of the lateral rectus muscle. However, some smaller subbranches run as far as the muscle's insertion, and recurrent subbranches also reach its origin. With respect to their course to the muscle's origin or insertion, the smallest subbranches running within the muscle may be associated with innervation of the tendon. In the majority of cases (88%), superior and inferior subbranches of the abducens nerve overlapped in the central one-third of the lateral rectus muscle's width so that any clearly distinct anatomical segments of the muscle could be observed based on Sihler's technique. In the remaining 12% of specimens, superior and inferior groups of subbranches innervated two distinct compartments of the lateral rectus muscle with no overlapping. Dense, fan-shaped distribution of abducens nerve intramuscular subbranches can be observed within the lateral rectus muscle. Clin. Anat. 33:585-591, 2020. © 2019 Wiley Periodicals, Inc.
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Affiliation(s)
- Robert Haładaj
- Department of Normal and Clinical Anatomy, Interfaculty Chair of Anatomy and Histology, Medical University of Lodz, Łódź, Poland
| | - Grzegorz Wysiadecki
- Department of Normal and Clinical Anatomy, Interfaculty Chair of Anatomy and Histology, Medical University of Lodz, Łódź, Poland
| | - R Shane Tubbs
- Department of Neurosurgery, Seattle Science Foundation, Seattle, Washington
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33
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Abstract
Topographic maps are a basic organizational feature of nervous systems, and their construction involves both spatial and temporal cues. A recent study reports a novel mechanism of topographic map formation which relies on the timing of axon initiation.
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Affiliation(s)
- Kristen P D'Elia
- Neuroscience Institute, Department of Neuroscience and Physiology, NYU School of Medicine, New York, NY 10016, USA
| | - Jeremy S Dasen
- Neuroscience Institute, Department of Neuroscience and Physiology, NYU School of Medicine, New York, NY 10016, USA.
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Martinez-Chavez E, Scheerer C, Wizenmann A, Blaess S. The zinc-finger transcription factor GLI3 is a regulator of precerebellar neuronal migration. Development 2018; 145:dev.166033. [PMID: 30470704 DOI: 10.1242/dev.166033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 11/15/2018] [Indexed: 01/24/2023]
Abstract
Hindbrain precerebellar neurons arise from progenitor pools at the dorsal edge of the embryonic hindbrain: the caudal rhombic lip. These neurons follow distinct migratory routes to establish nuclei that provide climbing or mossy fiber inputs to the cerebellum. Gli3, a zinc-finger transcription factor in the Sonic hedgehog signaling pathway, is an important regulator of dorsal brain development. We demonstrate that in Gli3-null mutant mice, disrupted neuronal migratory streams lead to a disorganization of precerebellar nuclei. Precerebellar progenitors are properly established in Gli3-null embryos and, using conditional gene inactivation, we provide evidence that Gli3 does not play a cell-autonomous role in migrating precerebellar neurons. Thus, GLI3 likely regulates the development of other hindbrain structures, such as non-precerebellar nuclei or cranial ganglia and their respective projections, which may in turn influence precerebellar migration. Although the organization of non-precerebellar hindbrain nuclei appears to be largely unaffected in absence of Gli3, trigeminal ganglia and their central descending tracts are disrupted. We show that rostrally migrating precerebellar neurons are normally in close contact with these tracts, but are detached in Gli3-null embryos.
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Affiliation(s)
- Erick Martinez-Chavez
- Institute of Reconstructive Neurobiology, University of Bonn Medical Center, 53127 Bonn, Germany
| | - Claudia Scheerer
- Institute of Reconstructive Neurobiology, University of Bonn Medical Center, 53127 Bonn, Germany
| | - Andrea Wizenmann
- Institute of Clinical Anatomy and Cell Analysis, Department of Anatomy, University of Tübingen, 72074 Tübingen, Germany
| | - Sandra Blaess
- Institute of Reconstructive Neurobiology, University of Bonn Medical Center, 53127 Bonn, Germany
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Frank MM, Goodrich LV. Talking back: Development of the olivocochlear efferent system. WILEY INTERDISCIPLINARY REVIEWS. DEVELOPMENTAL BIOLOGY 2018; 7:e324. [PMID: 29944783 PMCID: PMC6185769 DOI: 10.1002/wdev.324] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Revised: 04/27/2018] [Accepted: 05/17/2018] [Indexed: 02/02/2023]
Abstract
Developing sensory systems must coordinate the growth of neural circuitry spanning from receptors in the peripheral nervous system (PNS) to multilayered networks within the central nervous system (CNS). This breadth presents particular challenges, as nascent processes must navigate across the CNS-PNS boundary and coalesce into a tightly intermingled wiring pattern, thereby enabling reliable integration from the PNS to the CNS and back. In the auditory system, feedforward spiral ganglion neurons (SGNs) from the periphery collect sound information via tonotopically organized connections in the cochlea and transmit this information to the brainstem for processing via the VIII cranial nerve. In turn, feedback olivocochlear neurons (OCNs) housed in the auditory brainstem send projections into the periphery, also through the VIII nerve. OCNs are motor neuron-like efferent cells that influence auditory processing within the cochlea and protect against noise damage in adult animals. These aligned feedforward and feedback systems develop in parallel, with SGN central axons reaching the developing auditory brainstem around the same time that the OCN axons extend out toward the developing inner ear. Recent findings have begun to unravel the genetic and molecular mechanisms that guide OCN development, from their origins in a generic pool of motor neuron precursors to their specialized roles as modulators of cochlear activity. One recurrent theme is the importance of efferent-afferent interactions, as afferent SGNs guide OCNs to their final locations within the sensory epithelium, and efferent OCNs shape the activity of the developing auditory system. This article is categorized under: Nervous System Development > Vertebrates: Regional Development.
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Guidance of motor axons: where do we stand? CURRENT OPINION IN PHYSIOLOGY 2018. [DOI: 10.1016/j.cophys.2018.06.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Díaz C, Puelles L. Segmental Analysis of the Vestibular Nerve and the Efferents of the Vestibular Complex. Anat Rec (Hoboken) 2018; 302:472-484. [DOI: 10.1002/ar.23828] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Carmen Díaz
- Department of Medical Sciences, School of Medicine/Institute for Research in Neurological Disabilities; University of Castilla-La Mancha; Albacete 02006 Spain
| | - Luis Puelles
- Department of Human Anatomy and Psychobiology and IMIB-Arrixaca Institute, School of Medicine; University of Murcia; Murcia E30071 Spain
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De Santis R, Garone MG, Pagani F, de Turris V, Di Angelantonio S, Rosa A. Direct conversion of human pluripotent stem cells into cranial motor neurons using a piggyBac vector. Stem Cell Res 2018; 29:189-196. [DOI: 10.1016/j.scr.2018.04.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Revised: 03/23/2018] [Accepted: 04/24/2018] [Indexed: 12/11/2022] Open
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Molecular specification of facial branchial motor neurons in vertebrates. Dev Biol 2018; 436:5-13. [PMID: 29391164 DOI: 10.1016/j.ydbio.2018.01.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 01/27/2018] [Accepted: 01/28/2018] [Indexed: 02/02/2023]
Abstract
Orofacial muscles are critical for life-sustaining behaviors, such as feeding and breathing. Centuries of work by neuroanatomists and surgeons resulted in the mapping of bulbar motor neurons in the brainstem and the course of the cranial nerves that carry their axons. Despite the sophisticated understanding of the anatomy of the region, the molecular mechanisms that dictate the development and maturation of facial motor neurons remain poorly understood. This fundamental problem has been recently revisited by physiologists with novel techniques of studying the rhythmic contraction of orofacial muscles in relationship to breathing. The molecular understanding of facial motor neuron development will not only lead to the comprehension of the neural basis of facial expression but may also unlock new avenues to generate stem cell-derived replacements. This review summarizes the current understanding of molecular programs involved in facial motor neuron generation, migration, and maturation, including neural circuit assembly.
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Abstract
The mouse embryo forebrain is the most commonly employed system for studying mammalian neurogenesis during development. However, the highly folded forebrain neuroepithelium is not amenable to wholemount analysis to examine organ-wide neurogenesis patterns. Moreover, defining the mechanisms of forebrain neurogenesis is not necessarily predictive of neurogenesis in other parts of the brain; for example, due to the presence of forebrain-specific progenitor subtypes. The mouse hindbrain provides an alternative model for studying embryonic neurogenesis that is amenable to wholemount analysis, as well as tissue sections to observe the spatiotemporal distribution and behavior of neural progenitors. Moreover, it is easily dissected for other downstream applications, such as cell isolation or molecular biology analysis. As the mouse hindbrain can be readily analyzed in the vast number of cell lineage reporter and mutant mouse strains that have become available, it offers a powerful model for studying the cellular and molecular mechanisms of developmental neurogenesis in a mammalian organism. Here, we present a simple and quick method to use the mouse embryo hindbrain for analyzing mammalian neural progenitor cell (NPC) behavior in wholemount preparations and tissue sections.
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Haładaj R, Wysiadecki G, Polguj M, Topol M. Bilateral muscular slips between superior and inferior rectus muscles: case report with discussion on classification of accessory rectus muscles within the orbit. Surg Radiol Anat 2018; 40:855-862. [PMID: 29368252 PMCID: PMC5996005 DOI: 10.1007/s00276-018-1976-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 01/13/2018] [Indexed: 01/19/2023]
Abstract
Accessory rectus muscles have rarely been reported as muscular ‘bands’ or ‘slips’ originating from the common tendinous ring (annulus of Zinn) and inserting in atypical location. This group of muscles is innervated by the inferior branch of the oculomotor nerve, lies on lateral side of the optic nerve and inserts in rectus muscles. Since there are only few descriptions of such unusual findings in the medical literature, the anatomical data on accessory rectus muscles is limited. Furthermore, existing reports vary in terms of studied objects (cadavers or living subjects), medical history (absence or presence of ocular movement disorders or eye movement abnormalities) and details of anatomical description. This report complements earlier publications and provides complete anatomical description of the accessory rectus muscle observed bilaterally during the dissection of a 68-year-old male cadaver with no eye movement abnormalities reported in the medical history. The accessory rectus muscle was divided into two ‘slips’ or ‘heads’—superior and inferior—running in the sagittal plane (laterally to the optic nerve and the main trunk of the ophthalmic artery) and attached to the superior and inferior rectus muscles. Noticeable thickening of both superior and inferior rectus muscles at the insertion point of the accessory muscle heads was observed only in the sagittal plane. On both sides, the inferior head of the accessory rectus muscle was innervated by one of sub-branches derived from the inferior branch of the oculomotor nerve. No sub-branches to the superior head were macroscopically observed during the dissection. The classification, embryological background and clinical relevance of this variation have been discussed.
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Affiliation(s)
- Robert Haładaj
- Department of Normal and Clinical Anatomy, Interfaculty Chair of Anatomy and Histology, Medical University of Lodz, ul. Narutowicza 60, 90-136, Łódź, Poland
| | - Grzegorz Wysiadecki
- Department of Normal and Clinical Anatomy, Interfaculty Chair of Anatomy and Histology, Medical University of Lodz, ul. Narutowicza 60, 90-136, Łódź, Poland.
| | - Michał Polguj
- Department of Angiology, Interfaculty Chair of Anatomy and Histology, Medical University of Lodz, Łódź, Poland
| | - Mirosław Topol
- Department of Normal and Clinical Anatomy, Interfaculty Chair of Anatomy and Histology, Medical University of Lodz, ul. Narutowicza 60, 90-136, Łódź, Poland
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Kim M, Bjorke B, Mastick GS. Motor neuron migration and positioning mechanisms: New roles for guidance cues. Semin Cell Dev Biol 2017; 85:78-83. [PMID: 29141180 DOI: 10.1016/j.semcdb.2017.11.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Accepted: 11/10/2017] [Indexed: 11/24/2022]
Abstract
Motor neurons differentiate from progenitor cells and cluster as motor nuclei, settling next to the floor plate in the brain stem and spinal cord. Although precise positioning of motor neurons is critical for their functional input and output, the molecular mechanisms that guide motor neurons to their proper positions remain poorly understood. Here, we review recent evidence of motor neuron positioning mechanisms, highlighting situations in which motor neuron cell bodies can migrate, and experiments that show that their migration is regulated by axon guidance cues. The view that emerges is that motor neurons are actively trapped or restricted in static positions, as the cells balance a push in the dorsal direction by repulsive Slit/Robo cues and a pull in the ventral direction by attractive Netrin-1/DCC cues. These new functions of guidance cues are necessary fine-tuning to set up patterns of motor neurons at their proper positions in the neural tube during embryogenesis.
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Affiliation(s)
- Minkyung Kim
- Department of Biology, University of Nevada, Reno, NV 89557, USA.
| | - Brielle Bjorke
- Neuroscience Program, Carleton College, Northfield, MN 55057, USA
| | - Grant S Mastick
- Department of Biology, University of Nevada, Reno, NV 89557, USA
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Montague K, Lowe AS, Uzquiano A, Knüfer A, Astick M, Price SR, Guthrie S. The assembly of developing motor neurons depends on an interplay between spontaneous activity, type II cadherins and gap junctions. Development 2017; 144:830-836. [PMID: 28246212 DOI: 10.1242/dev.144063] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Accepted: 01/10/2017] [Indexed: 01/12/2023]
Abstract
A core structural and functional motif of the vertebrate central nervous system is discrete clusters of neurons or 'nuclei'. Yet the developmental mechanisms underlying this fundamental mode of organisation are largely unknown. We have previously shown that the assembly of motor neurons into nuclei depends on cadherin-mediated adhesion. Here, we demonstrate that the emergence of mature topography among motor nuclei involves a novel interplay between spontaneous activity, cadherin expression and gap junction communication. We report that nuclei display spontaneous calcium transients, and that changes in the activity patterns coincide with the course of nucleogenesis. We also find that these activity patterns are disrupted by manipulating cadherin or gap junction expression. Furthermore, inhibition of activity disrupts nucleogenesis, suggesting that activity feeds back to maintain integrity among motor neurons within a nucleus. Our study suggests that a network of interactions between cadherins, gap junctions and spontaneous activity governs neuron assembly, presaging circuit formation.
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Affiliation(s)
- Karli Montague
- Wolfson Centre for Age-related Diseases, King's College London, Guy's Hospital Campus, London SE1 1UL, UK
| | - Andrew S Lowe
- Department of Developmental Neurobiology, King's College London, Guy's Hospital Campus, London SE1 1UL, UK
| | - Ana Uzquiano
- École de Neuroscience-Paris Île-de-France, ENP-DIM, 15 Rue de L'École de Médécine, Paris 75006, France
| | - Athene Knüfer
- Department of Developmental Neurobiology, King's College London, Guy's Hospital Campus, London SE1 1UL, UK
| | - Marc Astick
- Institut de Recherche Interdisciplinaire en Biologie Humaine et Moléculaire, Université de Bruxelles, Route de Lennik 808, Bruxelles B1070, Belgium
| | - Stephen R Price
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Sarah Guthrie
- Department of Developmental Neurobiology, King's College London, Guy's Hospital Campus, London SE1 1UL, UK
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Allen JR, Bhattacharyya KD, Asante E, Almadi B, Schafer K, Davis J, Cox J, Voigt M, Viator JA, Chandrasekhar A. Role of branchiomotor neurons in controlling food intake of zebrafish larvae. J Neurogenet 2017; 31:128-137. [PMID: 28812416 PMCID: PMC5942883 DOI: 10.1080/01677063.2017.1358270] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 07/18/2017] [Indexed: 10/19/2022]
Abstract
The physical act of eating or feeding involves the coordinated action of several organs like eyes and jaws, and associated neural networks. Moreover, the activity of the neural networks controlling jaw movements (branchiomotor circuits) is regulated by the visual, olfactory, gustatory and hypothalamic systems, which are largely well characterized at the physiological level. By contrast, the behavioral output of the branchiomotor circuits and the functional consequences of disruption of these circuits by abnormal neural development are poorly understood. To begin to address these questions, we sought to evaluate the feeding ability of zebrafish larvae, a direct output of the branchiomotor circuits, and developed a qualitative assay for measuring food intake in zebrafish larvae at 7 days post-fertilization. We validated the assay by examining the effects of ablating the branchiomotor neurons. Metronidazole-mediated ablation of nitroreductase-expressing branchiomotor neurons resulted in a predictable reduction in food intake without significantly affecting swimming ability, indicating that the assay is robust. Laser-mediated ablation of trigeminal motor neurons resulted in a significant decrease in food intake, indicating that the assay is sensitive. Importantly, in larvae of a genetic mutant with severe loss of branchiomotor neurons, food intake was abolished. These studies establish a foundation for dissecting the neural circuits driving a motor behavior essential for survival.
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Affiliation(s)
- James R. Allen
- Division of Biological Sciences, and Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Kiran D. Bhattacharyya
- Department of Biological Engineering, and Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Emilia Asante
- Division of Biological Sciences, and Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Badr Almadi
- Division of Biological Sciences, and Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Kyle Schafer
- Division of Biological Sciences, and Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Jeremy Davis
- Division of Biological Sciences, and Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Jane Cox
- Department of Pharmacology and Physiology, St. Louis University School of Medicine, St. Louis, MO 63104, USA
| | - Mark Voigt
- Department of Pharmacology and Physiology, St. Louis University School of Medicine, St. Louis, MO 63104, USA
| | - John A. Viator
- Department of Biological Engineering, and Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
- Biomedical Engineering Program, Duquesne University, Pittsburgh, PA 15282, USA
| | - Anand Chandrasekhar
- Division of Biological Sciences, and Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
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45
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Seven pass Cadherins CELSR1-3. Semin Cell Dev Biol 2017; 69:102-110. [PMID: 28716607 DOI: 10.1016/j.semcdb.2017.07.014] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Revised: 07/12/2017] [Accepted: 07/13/2017] [Indexed: 11/20/2022]
Abstract
Cadherin EGF LAG seven-pass G-type receptors 1, 2 and 3 (CELSR1-3) form a family of three atypical cadherins with multiple functions in epithelia and in the nervous system. During the past decade, evidence has accumulated for a key role of CELSR1 in epithelial planar cell polarity (PCP), and for CELSR2 and CELSR3 in ciliogenesis and neural development, especially neuron migration and axon guidance in the central, peripheral and enteric nervous systems. Phenotypes in mutant mice indicate that CELSR proteins work in concert with FZD3 and FZD6, but several questions remain. Apart from PCP signaling pathways implicating CELSR1 that begin to be unraveled, little is known about other signals generated by CELSR2 and CELSR3. A crucial question concerns the putative ligands that trigger signaling, in particular what is the role of WNT factors. Another critical issue is the identification of novel intracellular pathways and effectors that relay and transmit signals in receptive cells? Answers to those questions should further our understanding of the role of those important molecules not only in development but also in regeneration and disease.
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Espinosa-Medina I, Saha O, Boismoreau F, Chettouh Z, Rossi F, Richardson WD, Brunet JF. The sacral autonomic outflow is sympathetic. Science 2017; 354:893-897. [PMID: 27856909 DOI: 10.1126/science.aah5454] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Accepted: 10/14/2016] [Indexed: 12/16/2022]
Abstract
A kinship between cranial and pelvic visceral nerves of vertebrates has been accepted for a century. Accordingly, sacral preganglionic neurons are considered parasympathetic, as are their targets in the pelvic ganglia that prominently control rectal, bladder, and genital functions. Here, we uncover 15 phenotypic and ontogenetic features that distinguish pre- and postganglionic neurons of the cranial parasympathetic outflow from those of the thoracolumbar sympathetic outflow in mice. By every single one, the sacral outflow is indistinguishable from the thoracolumbar outflow. Thus, the parasympathetic nervous system receives input from cranial nerves exclusively and the sympathetic nervous system from spinal nerves, thoracic to sacral inclusively. This simplified, bipartite architecture offers a new framework to understand pelvic neurophysiology as well as development and evolution of the autonomic nervous system.
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Affiliation(s)
- I Espinosa-Medina
- Institut de Biologie de l'École Normale Supérieure (IBENS), INSERM, CNRS, École Normale Supérieure, Paris Sciences et Lettres Research University, Paris, 75005 France
| | - O Saha
- Institut de Biologie de l'École Normale Supérieure (IBENS), INSERM, CNRS, École Normale Supérieure, Paris Sciences et Lettres Research University, Paris, 75005 France
| | - F Boismoreau
- Institut de Biologie de l'École Normale Supérieure (IBENS), INSERM, CNRS, École Normale Supérieure, Paris Sciences et Lettres Research University, Paris, 75005 France
| | - Z Chettouh
- Institut de Biologie de l'École Normale Supérieure (IBENS), INSERM, CNRS, École Normale Supérieure, Paris Sciences et Lettres Research University, Paris, 75005 France
| | - F Rossi
- Institut de Biologie de l'École Normale Supérieure (IBENS), INSERM, CNRS, École Normale Supérieure, Paris Sciences et Lettres Research University, Paris, 75005 France
| | - W D Richardson
- Wolfson Institute for Biomedical Research, University College London, London, UK
| | - J-F Brunet
- Institut de Biologie de l'École Normale Supérieure (IBENS), INSERM, CNRS, École Normale Supérieure, Paris Sciences et Lettres Research University, Paris, 75005 France.
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Oliveira MAP, Balling R, Smidt MP, Fleming RMT. Embryonic development of selectively vulnerable neurons in Parkinson's disease. NPJ Parkinsons Dis 2017; 3:21. [PMID: 28685157 PMCID: PMC5484687 DOI: 10.1038/s41531-017-0022-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 05/24/2017] [Accepted: 06/01/2017] [Indexed: 02/07/2023] Open
Abstract
A specific set of brainstem nuclei are susceptible to degeneration in Parkinson's disease. We hypothesise that neuronal vulnerability reflects shared phenotypic characteristics that confer selective vulnerability to degeneration. Neuronal phenotypic specification is mainly the cumulative result of a transcriptional regulatory program that is active during the development. By manual curation of the developmental biology literature, we comprehensively reconstructed an anatomically resolved cellular developmental lineage for the adult neurons in five brainstem regions that are selectively vulnerable to degeneration in prodromal or early Parkinson's disease. We synthesised the literature on transcription factors that are required to be active, or required to be inactive, in the development of each of these five brainstem regions, and at least two differentially vulnerable nuclei within each region. Certain transcription factors, e.g., Ascl1 and Lmx1b, seem to be required for specification of many brainstem regions that are susceptible to degeneration in early Parkinson's disease. Some transcription factors can even distinguish between differentially vulnerable nuclei within the same brain region, e.g., Pitx3 is required for specification of the substantia nigra pars compacta, but not the ventral tegmental area. We do not suggest that Parkinson's disease is a developmental disorder. In contrast, we consider identification of shared developmental trajectories as part of a broader effort to identify the molecular mechanisms that underlie the phenotypic features that are shared by selectively vulnerable neurons. Systematic in vivo assessment of fate determining transcription factors should be completed for all neuronal populations vulnerable to degeneration in early Parkinson's disease.
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Affiliation(s)
- Miguel A. P. Oliveira
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, 6 Avenue du Swing, Belvaux, L-4362 Luxembourg
| | - Rudi Balling
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, 6 Avenue du Swing, Belvaux, L-4362 Luxembourg
| | - Marten P. Smidt
- Department of Molecular Neuroscience, Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, Sciencepark 904, 1098 XH Amsterdam, The Netherlands
| | - Ronan M. T. Fleming
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, 6 Avenue du Swing, Belvaux, L-4362 Luxembourg
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48
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The origins of the vocal brain in humans. Neurosci Biobehav Rev 2017; 77:177-193. [DOI: 10.1016/j.neubiorev.2017.03.014] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 02/15/2017] [Accepted: 03/22/2017] [Indexed: 01/13/2023]
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49
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Chilton JK, Guthrie S. Axons get ahead: Insights into axon guidance and congenital cranial dysinnervation disorders. Dev Neurobiol 2017; 77:861-875. [DOI: 10.1002/dneu.22477] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 12/07/2016] [Accepted: 12/07/2016] [Indexed: 11/12/2022]
Affiliation(s)
- John K. Chilton
- Wellcome Wolfson Centre for Medical Research; University of Exeter Medical School, Wellcome-Wolfson Centre for Medical Research; Exeter EX2 5DW United Kingdom
| | - Sarah Guthrie
- School of Life Sciences; University of Sussex; Falmer Brighton, BN1 9QG
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50
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Hawley ZCE, Campos-Melo D, Droppelmann CA, Strong MJ. MotomiRs: miRNAs in Motor Neuron Function and Disease. Front Mol Neurosci 2017; 10:127. [PMID: 28522960 PMCID: PMC5415563 DOI: 10.3389/fnmol.2017.00127] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2017] [Accepted: 04/18/2017] [Indexed: 12/12/2022] Open
Abstract
MiRNAs are key regulators of the mammalian transcriptome that have been increasingly linked to degenerative diseases of the motor neurons. Although many of the miRNAs currently incriminated as participants in the pathogenesis of these diseases are also important to the normal development and function of motor neurons, at present there is no knowledge of the complete miRNA profile of motor neurons. In this review, we examine the current understanding with respect to miRNAs that are specifically required for motor neuron development, function and viability, and provide evidence that these should be considered as a functional network of miRNAs which we have collectively termed MotomiRs. We will also summarize those MotomiRs currently known to be associated with both amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy (SMA), and discuss their potential use as biomarkers.
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Affiliation(s)
- Zachary C E Hawley
- Molecular Medicine Group, Robarts Research Institute, Schulich School of Medicine and Dentistry, Western UniversityLondon, ON, Canada
| | - Danae Campos-Melo
- Molecular Medicine Group, Robarts Research Institute, Schulich School of Medicine and Dentistry, Western UniversityLondon, ON, Canada
| | - Cristian A Droppelmann
- Molecular Medicine Group, Robarts Research Institute, Schulich School of Medicine and Dentistry, Western UniversityLondon, ON, Canada
| | - Michael J Strong
- Molecular Medicine Group, Robarts Research Institute, Schulich School of Medicine and Dentistry, Western UniversityLondon, ON, Canada.,Department of Pathology, Schulich School of Medicine and Dentistry, Western UniversityLondon, ON, Canada.,Department of Clinical Neurological Sciences, Schulich School of Medicine and Dentistry, Western UniversityLondon, ON, Canada
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