1
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Frith TJR, Briscoe J, Boezio GLM. From signalling to form: the coordination of neural tube patterning. Curr Top Dev Biol 2023; 159:168-231. [PMID: 38729676 DOI: 10.1016/bs.ctdb.2023.11.004] [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] [Indexed: 05/12/2024]
Abstract
The development of the vertebrate spinal cord involves the formation of the neural tube and the generation of multiple distinct cell types. The process starts during gastrulation, combining axial elongation with specification of neural cells and the formation of the neuroepithelium. Tissue movements produce the neural tube which is then exposed to signals that provide patterning information to neural progenitors. The intracellular response to these signals, via a gene regulatory network, governs the spatial and temporal differentiation of progenitors into specific cell types, facilitating the assembly of functional neuronal circuits. The interplay between the gene regulatory network, cell movement, and tissue mechanics generates the conserved neural tube pattern observed across species. In this review we offer an overview of the molecular and cellular processes governing the formation and patterning of the neural tube, highlighting how the remarkable complexity and precision of vertebrate nervous system arises. We argue that a multidisciplinary and multiscale understanding of the neural tube development, paired with the study of species-specific strategies, will be crucial to tackle the open questions.
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Affiliation(s)
| | - James Briscoe
- The Francis Crick Institute, London, United Kingdom.
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2
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Oldham S, Ball G. A phylogenetically-conserved axis of thalamocortical connectivity in the human brain. Nat Commun 2023; 14:6032. [PMID: 37758726 PMCID: PMC10533558 DOI: 10.1038/s41467-023-41722-8] [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: 05/03/2023] [Accepted: 09/15/2023] [Indexed: 09/29/2023] Open
Abstract
The thalamus enables key sensory, motor, emotive, and cognitive processes via connections to the cortex. These projection patterns are traditionally considered to originate from discrete thalamic nuclei, however recent work showing gradients of molecular and connectivity features in the thalamus suggests the organisation of thalamocortical connections occurs along a continuous dimension. By performing a joint decomposition of densely sampled gene expression and non-invasive diffusion tractography in the adult human thalamus, we define a principal axis of genetic and connectomic variation along a medial-lateral thalamic gradient. Projections along this axis correspond to an anterior-posterior cortical pattern and are aligned with electrophysiological properties of the cortex. The medial-lateral axis demonstrates phylogenetic conservation, reflects transitions in neuronal subtypes, and shows associations with neurodevelopment and common brain disorders. This study provides evidence for a supra-nuclear axis of thalamocortical organisation characterised by a graded transition in molecular properties and anatomical connectivity.
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Affiliation(s)
- Stuart Oldham
- Developmental Imaging, Murdoch Children's Research Institute, Parkville, VIC, Australia.
- The Turner Institute for Brain and Mental Health, School of Psychological Sciences and Monash Biomedical Imaging, Monash University, Clayton, VIC, Australia.
| | - Gareth Ball
- Developmental Imaging, Murdoch Children's Research Institute, Parkville, VIC, Australia
- Department of Paediatrics, University of Melbourne, Parkville, VIC, Australia
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3
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Sarrafha L, Neavin DR, Parfitt GM, Kruglikov IA, Whitney K, Reyes R, Coccia E, Kareva T, Goldman C, Tipon R, Croft G, Crary JF, Powell JE, Blanchard J, Ahfeldt T. Novel human pluripotent stem cell-derived hypothalamus organoids demonstrate cellular diversity. iScience 2023; 26:107525. [PMID: 37646018 PMCID: PMC10460991 DOI: 10.1016/j.isci.2023.107525] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 06/19/2023] [Accepted: 07/31/2023] [Indexed: 09/01/2023] Open
Abstract
The hypothalamus is a region of the brain that plays an important role in regulating body functions and behaviors. There is a growing interest in human pluripotent stem cells (hPSCs) for modeling diseases that affect the hypothalamus. Here, we established an hPSC-derived hypothalamus organoid differentiation protocol to model the cellular diversity of this brain region. Using an hPSC line with a tyrosine hydroxylase (TH)-TdTomato reporter for dopaminergic neurons (DNs) and other TH-expressing cells, we interrogated DN-specific pathways and functions in electrophysiologically active hypothalamus organoids. Single-cell RNA sequencing (scRNA-seq) revealed diverse neuronal and non-neuronal cell types in mature hypothalamus organoids. We identified several molecularly distinct hypothalamic DN subtypes that demonstrated different developmental maturities. Our in vitro 3D hypothalamus differentiation protocol can be used to study the development of this critical brain structure and can be applied to disease modeling to generate novel therapeutic approaches for disorders centered around the hypothalamus.
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Affiliation(s)
- Lily Sarrafha
- Nash Family Department of Neuroscience, Mount Sinai, New York, NY 10029, USA
- Department of Neurology, Mount Sinai, New York, NY 10029, USA
- Department of Cell, Developmental and Regenerative Biology, Mount Sinai, New York, NY 10029, USA
- Ronald M. Loeb Center for Alzheimer’s Disease, Mount Sinai, New York, NY 10029, USA
- Friedman Brain Institute, Mount Sinai, New York, NY 10029, USA
- Black Family Stem Cell Institute, Mount Sinai, New York, NY 10029, USA
| | - Drew R. Neavin
- Garvan-Weizmann Centre for Cellular Genomics, Garvan Institute of Medical Research, Darlinghurst, Sydney, NSW 2010, Australia
| | - Gustavo M. Parfitt
- Nash Family Department of Neuroscience, Mount Sinai, New York, NY 10029, USA
- Ronald M. Loeb Center for Alzheimer’s Disease, Mount Sinai, New York, NY 10029, USA
- Friedman Brain Institute, Mount Sinai, New York, NY 10029, USA
- Black Family Stem Cell Institute, Mount Sinai, New York, NY 10029, USA
| | | | - Kristen Whitney
- Nash Family Department of Neuroscience, Mount Sinai, New York, NY 10029, USA
- Ronald M. Loeb Center for Alzheimer’s Disease, Mount Sinai, New York, NY 10029, USA
- Friedman Brain Institute, Mount Sinai, New York, NY 10029, USA
- Department of Pathology, Molecular, and Cell-Based Medicine, Mount Sinai, New York, NY 10029, USA
| | - Ricardo Reyes
- Nash Family Department of Neuroscience, Mount Sinai, New York, NY 10029, USA
- Department of Neurology, Mount Sinai, New York, NY 10029, USA
- Department of Cell, Developmental and Regenerative Biology, Mount Sinai, New York, NY 10029, USA
- Ronald M. Loeb Center for Alzheimer’s Disease, Mount Sinai, New York, NY 10029, USA
- Friedman Brain Institute, Mount Sinai, New York, NY 10029, USA
- Black Family Stem Cell Institute, Mount Sinai, New York, NY 10029, USA
| | - Elena Coccia
- Nash Family Department of Neuroscience, Mount Sinai, New York, NY 10029, USA
- Department of Neurology, Mount Sinai, New York, NY 10029, USA
- Department of Cell, Developmental and Regenerative Biology, Mount Sinai, New York, NY 10029, USA
- Ronald M. Loeb Center for Alzheimer’s Disease, Mount Sinai, New York, NY 10029, USA
- Friedman Brain Institute, Mount Sinai, New York, NY 10029, USA
- Black Family Stem Cell Institute, Mount Sinai, New York, NY 10029, USA
| | - Tatyana Kareva
- Nash Family Department of Neuroscience, Mount Sinai, New York, NY 10029, USA
- Department of Neurology, Mount Sinai, New York, NY 10029, USA
- Department of Cell, Developmental and Regenerative Biology, Mount Sinai, New York, NY 10029, USA
- Ronald M. Loeb Center for Alzheimer’s Disease, Mount Sinai, New York, NY 10029, USA
- Friedman Brain Institute, Mount Sinai, New York, NY 10029, USA
- Black Family Stem Cell Institute, Mount Sinai, New York, NY 10029, USA
| | - Camille Goldman
- Nash Family Department of Neuroscience, Mount Sinai, New York, NY 10029, USA
- Department of Neurology, Mount Sinai, New York, NY 10029, USA
- Department of Cell, Developmental and Regenerative Biology, Mount Sinai, New York, NY 10029, USA
- Ronald M. Loeb Center for Alzheimer’s Disease, Mount Sinai, New York, NY 10029, USA
- Friedman Brain Institute, Mount Sinai, New York, NY 10029, USA
- Black Family Stem Cell Institute, Mount Sinai, New York, NY 10029, USA
| | - Regine Tipon
- New York Stem Cell Foundation, New York, NY 10019, USA
| | - Gist Croft
- New York Stem Cell Foundation, New York, NY 10019, USA
| | - John F. Crary
- Nash Family Department of Neuroscience, Mount Sinai, New York, NY 10029, USA
- Ronald M. Loeb Center for Alzheimer’s Disease, Mount Sinai, New York, NY 10029, USA
- Friedman Brain Institute, Mount Sinai, New York, NY 10029, USA
- Department of Pathology, Molecular, and Cell-Based Medicine, Mount Sinai, New York, NY 10029, USA
- Windreich Department of Artificial Intelligence and Human Health, Mount Sinai, New York, NY 10029, USA
| | - Joseph E. Powell
- Garvan-Weizmann Centre for Cellular Genomics, Garvan Institute of Medical Research, Darlinghurst, Sydney, NSW 2010, Australia
- UNSW Cellular Genomics Futures Institute, University of New South Wales, Kensington, Sydney, NSW 2052, Australia
| | - Joel Blanchard
- Nash Family Department of Neuroscience, Mount Sinai, New York, NY 10029, USA
- Department of Cell, Developmental and Regenerative Biology, Mount Sinai, New York, NY 10029, USA
- Ronald M. Loeb Center for Alzheimer’s Disease, Mount Sinai, New York, NY 10029, USA
- Friedman Brain Institute, Mount Sinai, New York, NY 10029, USA
- Black Family Stem Cell Institute, Mount Sinai, New York, NY 10029, USA
| | - Tim Ahfeldt
- Nash Family Department of Neuroscience, Mount Sinai, New York, NY 10029, USA
- Department of Neurology, Mount Sinai, New York, NY 10029, USA
- Department of Cell, Developmental and Regenerative Biology, Mount Sinai, New York, NY 10029, USA
- Ronald M. Loeb Center for Alzheimer’s Disease, Mount Sinai, New York, NY 10029, USA
- Friedman Brain Institute, Mount Sinai, New York, NY 10029, USA
- Black Family Stem Cell Institute, Mount Sinai, New York, NY 10029, USA
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4
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Gao J, Lu Y, Luo Y, Duan X, Chen P, Zhang X, Wu X, Qiu M, Shen W. β-Catenin and SOX2 Interaction Regulate Visual Experience-Dependent Cell Homeostasis in the Developing Xenopus Thalamus. Int J Mol Sci 2023; 24:13593. [PMID: 37686400 PMCID: PMC10488257 DOI: 10.3390/ijms241713593] [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: 07/31/2023] [Revised: 08/19/2023] [Accepted: 08/30/2023] [Indexed: 09/10/2023] Open
Abstract
In the vertebrate brain, sensory experience plays a crucial role in shaping thalamocortical connections for visual processing. However, it is still not clear how visual experience influences tissue homeostasis and neurogenesis in the developing thalamus. Here, we reported that the majority of SOX2-positive cells in the thalamus are differentiated neurons that receive visual inputs as early as stage 47 Xenopus. Visual deprivation (VD) for 2 days shifts the neurogenic balance toward proliferation at the expense of differentiation, which is accompanied by a reduction in nuclear-accumulated β-catenin in SOX2-positive neurons. The knockdown of β-catenin decreases the expression of SOX2 and increases the number of progenitor cells. Coimmunoprecipitation studies reveal the evolutionary conservation of strong interactions between β-catenin and SOX2. These findings indicate that β-catenin interacts with SOX2 to maintain homeostatic neurogenesis during thalamus development.
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Affiliation(s)
- Juanmei Gao
- Zhejiang Key Laboratory of Organ Development and Regeneration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China (M.Q.)
- College of Life and Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yufang Lu
- Zhejiang Key Laboratory of Organ Development and Regeneration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China (M.Q.)
| | - Yuhao Luo
- Zhejiang Key Laboratory of Organ Development and Regeneration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China (M.Q.)
| | - Xinyi Duan
- Zhejiang Key Laboratory of Organ Development and Regeneration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China (M.Q.)
| | - Peiyao Chen
- Zhejiang Key Laboratory of Organ Development and Regeneration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China (M.Q.)
| | - Xinyu Zhang
- Zhejiang Key Laboratory of Organ Development and Regeneration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China (M.Q.)
| | - Xiaohua Wu
- Zhejiang Key Laboratory of Organ Development and Regeneration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China (M.Q.)
| | - Mengsheng Qiu
- Zhejiang Key Laboratory of Organ Development and Regeneration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China (M.Q.)
- College of Life and Sciences, Zhejiang University, Hangzhou 310058, China
| | - Wanhua Shen
- Zhejiang Key Laboratory of Organ Development and Regeneration, College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China (M.Q.)
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5
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Kiral FR, Cakir B, Tanaka Y, Kim J, Yang WS, Wehbe F, Kang YJ, Zhong M, Sancer G, Lee SH, Xiang Y, Park IH. Generation of ventralized human thalamic organoids with thalamic reticular nucleus. Cell Stem Cell 2023; 30:677-688.e5. [PMID: 37019105 PMCID: PMC10329908 DOI: 10.1016/j.stem.2023.03.007] [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: 08/03/2022] [Revised: 02/06/2023] [Accepted: 03/09/2023] [Indexed: 04/07/2023]
Abstract
Human brain organoids provide unique platforms for modeling several aspects of human brain development and pathology. However, current brain organoid systems mostly lack the resolution to recapitulate the development of finer brain structures with subregional identity, including functionally distinct nuclei in the thalamus. Here, we report a method for converting human embryonic stem cells (hESCs) into ventral thalamic organoids (vThOs) with transcriptionally diverse nuclei identities. Notably, single-cell RNA sequencing revealed previously unachieved thalamic patterning with a thalamic reticular nucleus (TRN) signature, a GABAergic nucleus located in the ventral thalamus. Using vThOs, we explored the functions of TRN-specific, disease-associated genes patched domain containing 1 (PTCHD1) and receptor tyrosine-protein kinase (ERBB4) during human thalamic development. Perturbations in PTCHD1 or ERBB4 impaired neuronal functions in vThOs, albeit not affecting the overall thalamic lineage development. Together, vThOs present an experimental model for understanding nuclei-specific development and pathology in the thalamus of the human brain.
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Affiliation(s)
- Ferdi Ridvan Kiral
- Department of Genetics, Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06520, USA
| | - Bilal Cakir
- Department of Genetics, Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06520, USA
| | - Yoshiaki Tanaka
- Department of Medicine, Maisonneuve-Rosemont Hospital Research Centre, University of Montreal, Montreal, QC H1T 2M4, Canada
| | - Jonghun Kim
- Department of Genetics, Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06520, USA
| | - Woo Sub Yang
- Department of Genetics, Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06520, USA
| | - Fabien Wehbe
- Department of Medicine, Maisonneuve-Rosemont Hospital Research Centre, University of Montreal, Montreal, QC H1T 2M4, Canada
| | - Young-Jin Kang
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Mei Zhong
- Department of Cell Biology, Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06520, USA
| | - Gizem Sancer
- Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Sang-Hun Lee
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Yangfei Xiang
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China.
| | - In-Hyun Park
- Department of Genetics, Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06520, USA.
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6
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Jabr N, Gonzalez P, Kocot KM, Cameron CB. The embryology, metamorphosis, and muscle development of Schizocardium karankawa sp. nov. (Enteropneusta) from the Gulf of Mexico. EvoDevo 2023; 14:6. [PMID: 37076909 PMCID: PMC10114407 DOI: 10.1186/s13227-023-00212-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 04/11/2023] [Indexed: 04/21/2023] Open
Abstract
Schizocardium karankawa sp. nov. has been collected from subtidal muds of the Laguna Madre, Texas, and the Mississippi coast, Gulf of Mexico. The Texas population is reproductive from early February to mid-April. Gametes are liberated by a small incision in a gonad. Oocyte germinal vesicle breakdown is increased in the presence of sperm, and the highest fertilization success was in the artificial seawater Jamarin U. Manually dechorionated embryos develop normally. Development was asynchronous via a tornaria larva, metamorphosis and maintained to the juvenile worm 6 gill-pore stage. Phalloidin-labeled late-stage tornaria revealed retractor muscles that connect the pericardial sac with the apical tuft anteriorly, the oesophagus ventrally, and muscle cells of the early mesocoels. The muscle development of early juvenile worms began with dorso-lateral trunk muscles, lateral trunk bands, and sphincters around the gill pores and anus. Adult worms are characterized by a stomochord that bifurcates anteriorly into paired vermiform processes, gill bars that extend almost the entire dorsal to ventral branchial region resulting in a narrow ventral hypobranchial ridge, and an elaborate epibranchial organ with six zones of discrete cell types. The trunk has up to three rows of liver sacs, and lateral gonads. The acorn worm evo-devo model species Saccoglossus kowalevskii, Ptychodera flava, and Schizocardium californicum are phylogenetically distant with disparate life histories. S. karnakawa from S. californicum are phylogenetically close, and differences between them that become apparent as adult worms include the number of gill pores and hepatic sacs, and elaborations of the heart-kidney-stomochord complex. An important challenge for evolutionary developmental biology is to form links from phylogenetically distant and large-scale differences to phylogenetically close and small-scale differences. This description of the embryology, development, and adult morphology of S. karankawa permits investigations into how acorn worm development evolves at fine scales.
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Affiliation(s)
- Noura Jabr
- Département de Sciences Biologiques, Université de Montréal, C.P. 6128, Succ. Centre-Ville, Montréal, QC, H3C 3J7, Canada
| | - Paul Gonzalez
- Computational and Statistical Genomics Branch, Division of Intramural Research, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Kevin M Kocot
- Department of Biological Sciences and Alabama Museum of Natural History, University of Alabama, Tuscaloosa, Alabama, 35487, USA
| | - Christopher B Cameron
- Département de Sciences Biologiques, Université de Montréal, C.P. 6128, Succ. Centre-Ville, Montréal, QC, H3C 3J7, Canada.
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7
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Govek KW, Chen S, Sgourdou P, Yao Y, Woodhouse S, Chen T, Fuccillo MV, Epstein DJ, Camara PG. Developmental trajectories of thalamic progenitors revealed by single-cell transcriptome profiling and Shh perturbation. Cell Rep 2022; 41:111768. [PMID: 36476860 PMCID: PMC9880597 DOI: 10.1016/j.celrep.2022.111768] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Revised: 10/06/2022] [Accepted: 11/11/2022] [Indexed: 12/12/2022] Open
Abstract
The thalamus is the principal information hub of the vertebrate brain, with essential roles in sensory and motor information processing, attention, and memory. The complex array of thalamic nuclei develops from a restricted pool of neural progenitors. We apply longitudinal single-cell RNA sequencing and regional abrogation of Sonic hedgehog (Shh) to map the developmental trajectories of thalamic progenitors, intermediate progenitors, and post-mitotic neurons as they coalesce into distinct thalamic nuclei. These data reveal that the complex architecture of the thalamus is established early during embryonic brain development through the coordinated action of four cell differentiation lineages derived from Shh-dependent and -independent progenitors. We systematically characterize the gene expression programs that define these thalamic lineages across time and demonstrate how their disruption upon Shh depletion causes pronounced locomotor impairment resembling infantile Parkinson's disease. These results reveal key principles of thalamic development and provide mechanistic insights into neurodevelopmental disorders resulting from thalamic dysfunction.
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Affiliation(s)
- Kiya W. Govek
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, 3700 Hamilton Walk, Philadelphia, PA 19104, USA,Institute for Biomedical Informatics, Perelman School of Medicine, University of Pennsylvania, 3700 Hamilton Walk, Philadelphia, PA 19104, USA,These authors contributed equally
| | - Sixing Chen
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, 3700 Hamilton Walk, Philadelphia, PA 19104, USA,These authors contributed equally
| | - Paraskevi Sgourdou
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, 3700 Hamilton Walk, Philadelphia, PA 19104, USA
| | - Yao Yao
- Department of Animal and Dairy Science, Regenerative Bioscience Center, University of Georgia, 425 River Road, Athens, GA 30602, USA
| | - Steven Woodhouse
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, 3700 Hamilton Walk, Philadelphia, PA 19104, USA,Institute for Biomedical Informatics, Perelman School of Medicine, University of Pennsylvania, 3700 Hamilton Walk, Philadelphia, PA 19104, USA
| | - Tingfang Chen
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, 3700 Hamilton Walk, Philadelphia, PA 19104, USA
| | - Marc V. Fuccillo
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Douglas J. Epstein
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, 3700 Hamilton Walk, Philadelphia, PA 19104, USA,Correspondence: (D.J.E.), (P.G.C.)
| | - Pablo G. Camara
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, 3700 Hamilton Walk, Philadelphia, PA 19104, USA,Institute for Biomedical Informatics, Perelman School of Medicine, University of Pennsylvania, 3700 Hamilton Walk, Philadelphia, PA 19104, USA,Lead contact,Correspondence: (D.J.E.), (P.G.C.)
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8
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K27M in canonical and noncanonical H3 variants occurs in distinct oligodendroglial cell lineages in brain midline gliomas. Nat Genet 2022; 54:1865-1880. [PMID: 36471070 PMCID: PMC9742294 DOI: 10.1038/s41588-022-01205-w] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 09/16/2022] [Indexed: 12/12/2022]
Abstract
Canonical (H3.1/H3.2) and noncanonical (H3.3) histone 3 K27M-mutant gliomas have unique spatiotemporal distributions, partner alterations and molecular profiles. The contribution of the cell of origin to these differences has been challenging to uncouple from the oncogenic reprogramming induced by the mutation. Here, we perform an integrated analysis of 116 tumors, including single-cell transcriptome and chromatin accessibility, 3D chromatin architecture and epigenomic profiles, and show that K27M-mutant gliomas faithfully maintain chromatin configuration at developmental genes consistent with anatomically distinct oligodendrocyte precursor cells (OPCs). H3.3K27M thalamic gliomas map to prosomere 2-derived lineages. In turn, H3.1K27M ACVR1-mutant pontine gliomas uniformly mirror early ventral NKX6-1+/SHH-dependent brainstem OPCs, whereas H3.3K27M gliomas frequently resemble dorsal PAX3+/BMP-dependent progenitors. Our data suggest a context-specific vulnerability in H3.1K27M-mutant SHH-dependent ventral OPCs, which rely on acquisition of ACVR1 mutations to drive aberrant BMP signaling required for oncogenesis. The unifying action of K27M mutations is to restrict H3K27me3 at PRC2 landing sites, whereas other epigenetic changes are mainly contingent on the cell of origin chromatin state and cycling rate.
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9
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Transcriptional Profile of the Developing Subthalamic Nucleus. eNeuro 2022; 9:9/5/ENEURO.0193-22.2022. [PMID: 36257692 PMCID: PMC9581575 DOI: 10.1523/eneuro.0193-22.2022] [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: 05/12/2022] [Revised: 09/09/2022] [Accepted: 09/14/2022] [Indexed: 12/15/2022] Open
Abstract
The subthalamic nucleus (STN) is a small, excitatory nucleus that regulates the output of basal ganglia motor circuits. The functions of the STN and its role in the pathophysiology of Parkinson's disease are now well established. However, some basic characteristics like the developmental origin and molecular phenotype of neuronal subpopulations are still being debated. The classical model of forebrain development attributed the origin of STN within the diencephalon. Recent studies of gene expression patterns exposed shortcomings of the classical model. To accommodate these findings, the prosomeric model was developed. In this concept, STN develops within the hypothalamic primordium, which is no longer a part of the diencephalic primordium. This concept is further supported by the expression patterns of many transcription factors. It is interesting to note that many transcription factors involved in the development of the STN are also involved in the pathogenesis of neurodevelopmental disorders. Thus, the study of neurodevelopmental disorders could provide us with valuable information on the roles of these transcription factors in the development and maintenance of STN phenotype. In this review, we summarize historical theories about the developmental origin of the STN and interpret the gene expression data within the prosomeric conceptual framework. Finally, we discuss the importance of neurodevelopmental disorders for the development of the STN and its potential role in the pathophysiology of neurodevelopmental disorders.
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10
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Callejas-Marin A, Moreno-Bravo JA, Company V, Madrigal MP, Almagro-García F, Martínez S, Puelles E. Gli2-Mediated Shh Signaling Is Required for Thalamocortical Projection Guidance. Front Neuroanat 2022; 16:830758. [PMID: 35221935 PMCID: PMC8866834 DOI: 10.3389/fnana.2022.830758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 01/13/2022] [Indexed: 11/13/2022] Open
Abstract
The thalamocortical projections are part of the most important higher level processing connections in the vertebrates and follow a highly ordered pathway from their origin in the thalamus to the cerebral cortex. Their functional complexities are not only due to an extremely elaborate axon guidance process but also due to activity-dependent mechanisms. Gli2 is an intermediary transcription factor in the Sonic hedgehog (Shh) pathway. During neural early development, Shh has an important role in dorsoventral patterning, diencephalic anteroposterior patterning, and many later developmental processes, such as axon guidance and cell migration. Using a Gli2 knockout mouse line, we have studied the role of Shh signaling mediated by Gli2 in the development of the thalamocortical projections during embryonic development. In wild-type brains, we have described the normal trajectory of the thalamocortical axons into the context of the prosomeric model. Then, we have compared it with the altered thalamocortical axons course in Gli2 homozygous embryos. The thalamocortical axons followed different trajectories and were misdirected to other territories probably due to alterations in the Robo/Slit signaling mechanism. In conclusion, the alteration of Gli2-mediated Shh signaling produces an erroneous specification of several territories related with the thalamocortical axons. This is translated into a huge modification in the pathfinding signaling mechanisms needed for the correct wiring of the thalamocortical axons.
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Affiliation(s)
- Antuca Callejas-Marin
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas, Universidad Miguel Hernández de Elche, Elche, Spain
- Departamento de Anatomía, Biología Celular y Zoología, Facultad de Ciencias, Universidad de Extremadura, Badajoz, Spain
| | - Juan Antonio Moreno-Bravo
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas, Universidad Miguel Hernández de Elche, Elche, Spain
| | - Verónica Company
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas, Universidad Miguel Hernández de Elche, Elche, Spain
| | - M. Pilar Madrigal
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas, Universidad Miguel Hernández de Elche, Elche, Spain
| | - Francisca Almagro-García
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas, Universidad Miguel Hernández de Elche, Elche, Spain
| | - Salvador Martínez
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas, Universidad Miguel Hernández de Elche, Elche, Spain
| | - Eduardo Puelles
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas, Universidad Miguel Hernández de Elche, Elche, Spain
- *Correspondence: Eduardo Puelles,
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11
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Guy B, Zhang JS, Duncan LH, Johnston RJ. Human neural organoids: Models for developmental neurobiology and disease. Dev Biol 2021; 478:102-121. [PMID: 34181916 PMCID: PMC8364509 DOI: 10.1016/j.ydbio.2021.06.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Revised: 06/08/2021] [Accepted: 06/24/2021] [Indexed: 12/25/2022]
Abstract
Human organoids stand at the forefront of basic and translational research, providing experimentally tractable systems to study human development and disease. These stem cell-derived, in vitro cultures can generate a multitude of tissue and organ types, including distinct brain regions and sensory systems. Neural organoid systems have provided fundamental insights into molecular mechanisms governing cell fate specification and neural circuit assembly and serve as promising tools for drug discovery and understanding disease pathogenesis. In this review, we discuss several human neural organoid systems, how they are generated, advances in 3D imaging and bioengineering, and the impact of organoid studies on our understanding of the human nervous system.
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Affiliation(s)
- Brian Guy
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD, 21218, USA
| | - Jingliang Simon Zhang
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD, 21218, USA
| | - Leighton H Duncan
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Robert J Johnston
- Department of Biology, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD, 21218, USA.
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12
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Bakken TE, van Velthoven CTJ, Menon V, Hodge RD, Yao Z, Nguyen TN, Graybuck LT, Horwitz GD, Bertagnolli D, Goldy J, Yanny AM, Garren E, Parry S, Casper T, Shehata SI, Barkan ER, Szafer A, Levi BP, Dee N, Smith KA, Sunkin SM, Bernard A, Phillips J, Hawrylycz MJ, Koch C, Murphy GJ, Lein E, Zeng H, Tasic B. Single-cell and single-nucleus RNA-seq uncovers shared and distinct axes of variation in dorsal LGN neurons in mice, non-human primates, and humans. eLife 2021; 10:e64875. [PMID: 34473054 PMCID: PMC8412930 DOI: 10.7554/elife.64875] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 07/18/2021] [Indexed: 12/11/2022] Open
Abstract
Abundant evidence supports the presence of at least three distinct types of thalamocortical (TC) neurons in the primate dorsal lateral geniculate nucleus (dLGN) of the thalamus, the brain region that conveys visual information from the retina to the primary visual cortex (V1). Different types of TC neurons in mice, humans, and macaques have distinct morphologies, distinct connectivity patterns, and convey different aspects of visual information to the cortex. To investigate the molecular underpinnings of these cell types, and how these relate to differences in dLGN between human, macaque, and mice, we profiled gene expression in single nuclei and cells using RNA-sequencing. These efforts identified four distinct types of TC neurons in the primate dLGN: magnocellular (M) neurons, parvocellular (P) neurons, and two types of koniocellular (K) neurons. Despite extensively documented morphological and physiological differences between M and P neurons, we identified few genes with significant differential expression between transcriptomic cell types corresponding to these two neuronal populations. Likewise, the dominant feature of TC neurons of the adult mouse dLGN is high transcriptomic similarity, with an axis of heterogeneity that aligns with core vs. shell portions of mouse dLGN. Together, these data show that transcriptomic differences between principal cell types in the mature mammalian dLGN are subtle relative to the observed differences in morphology and cortical projection targets. Finally, alignment of transcriptome profiles across species highlights expanded diversity of GABAergic neurons in primate versus mouse dLGN and homologous types of TC neurons in primates that are distinct from TC neurons in mouse.
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Affiliation(s)
| | | | - Vilas Menon
- Allen Institute for Brain ScienceSeattleUnited States
- Department of Neurology, Columbia University Medical CenterNew YorkUnited States
| | | | - Zizhen Yao
- Allen Institute for Brain ScienceSeattleUnited States
| | | | | | - Gregory D Horwitz
- Washington National Primate Research Center and Department of Physiology and Biophysics, University of WashingtonSeattleUnited States
| | | | - Jeff Goldy
- Allen Institute for Brain ScienceSeattleUnited States
| | | | - Emma Garren
- Allen Institute for Brain ScienceSeattleUnited States
| | - Sheana Parry
- Allen Institute for Brain ScienceSeattleUnited States
| | - Tamara Casper
- Allen Institute for Brain ScienceSeattleUnited States
| | | | | | - Aaron Szafer
- Allen Institute for Brain ScienceSeattleUnited States
| | - Boaz P Levi
- Allen Institute for Brain ScienceSeattleUnited States
| | - Nick Dee
- Allen Institute for Brain ScienceSeattleUnited States
| | | | | | - Amy Bernard
- Allen Institute for Brain ScienceSeattleUnited States
| | - John Phillips
- Allen Institute for Brain ScienceSeattleUnited States
| | | | - Christof Koch
- Allen Institute for Brain ScienceSeattleUnited States
| | - Gabe J Murphy
- Allen Institute for Brain ScienceSeattleUnited States
| | - Ed Lein
- Allen Institute for Brain ScienceSeattleUnited States
| | - Hongkui Zeng
- Allen Institute for Brain ScienceSeattleUnited States
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13
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Puelles L, Diaz C, Stühmer T, Ferran JL, Martínez‐de la Torre M, Rubenstein JLR. LacZ-reporter mapping of Dlx5/6 expression and genoarchitectural analysis of the postnatal mouse prethalamus. J Comp Neurol 2021; 529:367-420. [PMID: 32420617 PMCID: PMC7671952 DOI: 10.1002/cne.24952] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 05/10/2020] [Accepted: 05/11/2020] [Indexed: 12/22/2022]
Abstract
We present here a thorough and complete analysis of mouse P0-P140 prethalamic histogenetic subdivisions and corresponding nuclear derivatives, in the context of local tract landmarks. The study used as fundamental material brains from a transgenic mouse line that expresses LacZ under the control of an intragenic enhancer of Dlx5 and Dlx6 (Dlx5/6-LacZ). Subtle shadings of LacZ signal, jointly with pan-DLX immunoreaction, and several other ancillary protein or RNA markers, including Calb2 and Nkx2.2 ISH (for the prethalamic eminence, and derivatives of the rostral zona limitans shell domain, respectively) were mapped across the prethalamus. The resulting model of the prethalamic region postulates tetrapartite rostrocaudal and dorsoventral subdivisions, as well as a tripartite radial stratification, each cell population showing a characteristic molecular profile. Some novel nuclei are proposed, and some instances of potential tangential cell migration were noted.
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Affiliation(s)
- Luis Puelles
- Department of Human Anatomy and Psychobiology and IMIB‐Arrixaca InstituteUniversity of MurciaMurciaSpain
| | - Carmen Diaz
- Department of Medical Sciences, School of Medicine and Institute for Research in Neurological DisabilitiesUniversity of Castilla‐La ManchaAlbaceteSpain
| | - Thorsten Stühmer
- Nina Ireland Laboratory of Developmental Neurobiology, Department of PsychiatryUCSF Medical SchoolSan FranciscoCaliforniaUSA
| | - José L. Ferran
- Department of Human Anatomy and Psychobiology and IMIB‐Arrixaca InstituteUniversity of MurciaMurciaSpain
| | | | - John L. R. Rubenstein
- Nina Ireland Laboratory of Developmental Neurobiology, Department of PsychiatryUCSF Medical SchoolSan FranciscoCaliforniaUSA
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14
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Abstract
Hemichordates, along with echinoderms and chordates, belong to the lineage of bilaterians called the deuterostomes. Their phylogenetic position as an outgroup to chordates provides an opportunity to investigate the evolutionary origins of the chordate body plan and reconstruct ancestral deuterostome characters. The body plans of the hemichordates and chordates are organizationally divergent making anatomical comparisons very challenging. The developmental underpinnings of animal body plans are often more conservative than the body plans they regulate, and offer a novel data set for making comparisons between morphologically divergent body architectures. Here I review the hemichordate developmental data generated over the past 20 years that further test hypotheses of proposed morphological affinities between the two taxa, but also compare the conserved anteroposterior, dorsoventral axial patterning programs and germ layer specification programs. These data provide an opportunity to determine which developmental programs are ancestral deuterostome or bilaterian innovations, and which ones occurred in stem chordates or vertebrates representing developmental novelties of the chordate body plan.
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15
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Yaksi E, Jamali A, Diaz Verdugo C, Jurisch-Yaksi N. Past, present and future of zebrafish in epilepsy research. FEBS J 2021; 288:7243-7255. [PMID: 33394550 DOI: 10.1111/febs.15694] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 12/17/2020] [Accepted: 12/31/2020] [Indexed: 12/17/2022]
Abstract
Animal models contribute greatly to our understanding of brain development and function as well as its dysfunction in neurological diseases. Epilepsy research is a very good example of how animal models can provide us with a mechanistic understanding of the genes, molecules, and pathophysiological processes involved in disease. Over the course of the last two decades, zebrafish came in as a new player in epilepsy research, with an expanding number of laboratories using this animal to understand epilepsy and to discover new strategies for preventing seizures. Yet, zebrafish as a model offers a lot more for epilepsy research. In this viewpoint, we aim to highlight some key contributions of zebrafish to epilepsy research, and we want to emphasize the great untapped potential of this animal model for expanding these contributions. We hope that our suggestions will trigger further discussions between clinicians and researchers with a common goal to understand and cure epilepsy.
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Affiliation(s)
- Emre Yaksi
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
| | - Ahmed Jamali
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway.,Department of Neurology and Clinical Neurophysiology, St Olav University Hospital, Trondheim, Norway
| | - Carmen Diaz Verdugo
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
| | - Nathalie Jurisch-Yaksi
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway.,Department of Neurology and Clinical Neurophysiology, St Olav University Hospital, Trondheim, Norway.,Department of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
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16
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Lin YC, Wu CY, Hu CH, Pai TW, Chen YR, Wang WD. Integrated Hypoxia Signaling and Oxidative Stress in Developmental Neurotoxicity of Benzo[a]Pyrene in Zebrafish Embryos. Antioxidants (Basel) 2020; 9:antiox9080731. [PMID: 32796530 PMCID: PMC7464806 DOI: 10.3390/antiox9080731] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 08/08/2020] [Accepted: 08/09/2020] [Indexed: 12/14/2022] Open
Abstract
Benzo[a]pyrene (B[a]P) is a polycyclic aromatic hydrocarbon formed by the incomplete combustion of organic matter. Environmental B[a]P contamination poses a serious health risk to many organisms because the pollutant may negatively affect many physiological systems. As such, chronic exposure to B[a]P is known to lead to locomotor dysfunction and neurodegeneration in several organisms. In this study, we used the zebrafish model to delineate the acute toxic effects of B[a]P on the developing nervous system. We found that embryonic exposure of B[a]P downregulates shh and isl1, causing morphological hypoplasia in the telencephalon, ventral thalamus, hypothalamus, epiphysis and posterior commissure. Moreover, hypoxia-inducible factors (hif1a and hif2a) are repressed upon embryonic exposure of B[a]P, leading to reduced expression of the Hif-target genes, epo and survivin, which are associated with neural differentiation and maintenance. During normal embryogenesis, low-level oxidative stress regulates neuronal development and function. However, our experiments revealed that embryonic oxidative stress is greatly increased in B[a]P-treated embryos. The expression of catalase was decreased and sod1 expression increased in B[a]P-treated embryos. These transcriptional changes were coincident with increased embryonic levels of H2O2 and malondialdehyde, with the levels in B[a]P-treated fish similar to those in embryos treated with 120-μM H2O2. Together, our data suggest that reduced Hif signaling and increased oxidative stress are involved in B[a]P-induced acute neurotoxicity during embryogenesis.
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Affiliation(s)
- Yi-Chen Lin
- Department of Bioagricultural Sciences, National Chiayi University, Chiayi City 60004, Taiwan;
| | - Chang-Yi Wu
- Department of Biological Sciences, National Sun Yat-sen University, Kaohsiung 80424, Taiwan;
| | - Chin-Hwa Hu
- Department of Bioscience and Biotechnology, National Taiwan Ocean University, Keelung 20224, Taiwan;
| | - Tun-Wen Pai
- Department of Computer Science and Engineering, National Taiwan Ocean University, Keelung 20224, Taiwan;
- Department of Computer Science and Information Engineering, National Taipei University of Technology, Taipei 10608, Taiwan
| | - Yet-Ran Chen
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei 11529, Taiwan;
| | - Wen-Der Wang
- Department of Bioagricultural Sciences, National Chiayi University, Chiayi City 60004, Taiwan;
- Correspondence:
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17
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Morona R, Bandín S, López JM, Moreno N, González A. Amphibian thalamic nuclear organization during larval development and in the adult frog Xenopus laevis: Genoarchitecture and hodological analysis. J Comp Neurol 2020; 528:2361-2403. [PMID: 32162311 DOI: 10.1002/cne.24899] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2020] [Revised: 03/03/2020] [Accepted: 03/04/2020] [Indexed: 12/18/2022]
Abstract
The early patterning of the thalamus during embryonic development defines rostral and caudal progenitor domains, which are conserved from fishes to mammals. However, the subsequent developmental mechanisms that lead to the adult thalamic configuration have only been investigated for mammals and other amniotes. In this study, we have analyzed in the anuran amphibian Xenopus laevis (an anamniote vertebrate), through larval and postmetamorphic development, the progressive regional expression of specific markers for the rostral (GABA, GAD67, Lhx1, and Nkx2.2) and caudal (Gbx2, VGlut2, Lhx2, Lhx9, and Sox2) domains. In addition, the regional distributions at different developmental stages of other markers such as calcium binding proteins and neuropeptides, helped the identification of thalamic nuclei. It was observed that the two embryonic domains were progressively specified and compartmentalized during premetamorphosis, and cell subpopulations characterized by particular gene expression combinations were located in periventricular, intermediate and superficial strata. During prometamorphosis, three dorsoventral tiers formed from the caudal domain and most pronuclei were defined, which were modified into the definitive nuclear configuration through the metamorphic climax. Mixed cell populations originated from the rostral and caudal domains constitute most of the final nuclei and allowed us to propose additional subdivisions in the adult thalamus, whose main afferent and efferent connections were assessed by tracing techniques under in vitro conditions. This study corroborates shared features of early gene expression patterns in the thalamus between Xenopus and mouse, however, the dynamic changes in gene expression observed at later stages in the amphibian support mechanisms different from those of mammals.
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Affiliation(s)
- Ruth Morona
- Department of Cell Biology, Faculty of Biology, University Complutense of Madrid, Madrid, Spain
| | - Sandra Bandín
- Department of Cell Biology, Faculty of Biology, University Complutense of Madrid, Madrid, Spain
| | - Jesús M López
- Department of Cell Biology, Faculty of Biology, University Complutense of Madrid, Madrid, Spain
| | - Nerea Moreno
- Department of Cell Biology, Faculty of Biology, University Complutense of Madrid, Madrid, Spain
| | - Agustín González
- Department of Cell Biology, Faculty of Biology, University Complutense of Madrid, Madrid, Spain
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18
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12-h abstinence-induced functional connectivity density changes and craving in young smokers: a resting-state study. Brain Imaging Behav 2020; 13:953-962. [PMID: 29926324 DOI: 10.1007/s11682-018-9911-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Studying the neural correlates of craving to smoke is of great importance to improve treatment outcomes in smoking addiction. According to previous studies, the critical roles of striatum and frontal brain regions had been revealed in addiction. However, few studies focused on the hub of brain regions in the 12 h abstinence induced craving in young smokers. Thirty-one young male smokers were enrolled in the present study. A within-subject experiment design was carried out to compare functional connectivity density between 12-h smoking abstinence and smoking satiety conditions during resting state in young adult smokers by using functional connectivity density mapping (FCDM). Then, the functional connectivity density changes during smoking abstinence versus satiety were further used to examine correlations with abstinence-induced changes in subjective craving. We found young adult smokers in abstinence state (vs satiety) had higher local functional connectivity density (lFCD) and global functional connectivity density (gFCD) in brain regions including striatal subregions (i.e., bilateral caudate and putamen), frontal regions (i.e., anterior cingulate cortex (ACC) and orbital frontal cortex (OFC)) and bilateral insula. We also found higher lFCD during smoking abstinence (vs satiety) in bilateral thalamus. Additionally, the lFCD changes of the left ACC, bilateral caudate and right OFC were positively correlated with the changes in craving induced by abstinence (i.e., abstinence minus satiety) in young adult smokers. The present findings improve the understanding of the effects of acute smoking abstinence on the hubs of brain gray matter in the abstinence-induces craving and may contribute new insights into the neural mechanism of abstinence-induced craving in young smokers in smoking addiction.
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19
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Itoyama T, Fukui M, Kawaguchi M, Kaneko S, Sugahara F, Murakami Y. FGF- and SHH-based molecular signals regulate barbel and craniofacial development in catfish. ZOOLOGICAL LETTERS 2019; 5:19. [PMID: 31223485 PMCID: PMC6570838 DOI: 10.1186/s40851-019-0135-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Accepted: 05/19/2019] [Indexed: 06/09/2023]
Abstract
BACKGROUND Catfish (Siluriformes) are characterized by unique morphologies, including enlarged jaws with movable barbels and taste buds covering the entire body surface. Evolution of these characteristics was a crucial step in their adaptive radiation to freshwater environments. However, the developmental processes of the catfish craniofacial region and taste buds remain to be elucidated; moreover, little is known about the molecular mechanisms underlying the morphogenesis of these structures. RESULTS In Amur catfish (Silurus asotus), three pairs of barbel primordia are formed by 2 days post-fertilization (dpf). Innervation of the peripheral nerves and formation of muscle precursors are also established during early development. Taste buds from the oral region to the body trunk are formed by 4 dpf. We then isolated catfish cognates Shh (SaShh) and Fgf8 (SaFgf8), which are expressed in maxillary barbel primordium at 1-2 dpf. Further, SHH signal inhibition induces reduction of mandibular barbels with abnormal morphology of skeletal elements, whereas it causes no apparent abnormality in the trigeminal and facial nerve morphology. We also found that mandibular barbel lengths and number of taste buds are reduced by FGF inhibition, as seen in SHH signal inhibition. However, unlike with SHH inhibition, the abnormal morphology of the trigeminal and facial nerves was observed in FGF signal-inhibited embryos. CONCLUSION The developmental processes of Amur catfish are consistent with those reported for other catfish species. Thus, developmental aspects of craniofacial structures and taste buds may be conserved in Siluriformes. Our findings also suggest that SHH signaling plays a crucial role in the formation of barbels and taste buds, without affecting nerve projection, while FGF signaling is required for the development of barbels, taste buds, and branchial nerves. Thus, SHH and FGF signaling plays key roles in the ontogenesis and evolution of some catfish-specific characteristics.
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Affiliation(s)
- Tatsuya Itoyama
- Graduate School of Science and Engineering, Ehime University, 2-5 Bunkyo-cho, Matsuyama, 790-8577 Japan
| | - Makiko Fukui
- Graduate School of Science and Engineering, Ehime University, 2-5 Bunkyo-cho, Matsuyama, 790-8577 Japan
| | - Masahumi Kawaguchi
- Department of Anatomy and Neuroscience, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, 930-0194 Japan
| | - Saki Kaneko
- Graduate School of Science and Engineering, Ehime University, 2-5 Bunkyo-cho, Matsuyama, 790-8577 Japan
| | - Fumiaki Sugahara
- Division of Biology, Hyogo College of Medicine, Nishinomiya, 663-8501 Japan
| | - Yasunori Murakami
- Graduate School of Science and Engineering, Ehime University, 2-5 Bunkyo-cho, Matsuyama, 790-8577 Japan
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20
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Nakagawa Y. Development of the thalamus: From early patterning to regulation of cortical functions. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2019; 8:e345. [PMID: 31034163 DOI: 10.1002/wdev.345] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Revised: 03/28/2019] [Accepted: 04/01/2019] [Indexed: 02/06/2023]
Abstract
The thalamus is a brain structure of the vertebrate diencephalon that plays a central role in regulating diverse functions of the cerebral cortex. In traditional view of vertebrate neuroanatomy, the thalamus includes three regions, dorsal thalamus, ventral thalamus, and epithalamus. Recent molecular embryological studies have redefined the thalamus and the associated axial nomenclature of the diencephalon in the context of forebrain patterning. This new view has provided a useful conceptual framework for studies on molecular mechanisms of patterning, neurogenesis and fate specification in the thalamus as well as the guidance mechanisms for thalamocortical axons. Additionally, the availability of genetic tools in mice has led to important findings on how thalamic development is linked to the development of other brain regions, particularly the cerebral cortex. This article will give an overview of the organization of the embryonic thalamus and how progenitor cells in the thalamus generate neurons that are organized into discrete nuclei. I will then discuss how thalamic development is orchestrated with the development of the cerebral cortex and other brain regions. This article is categorized under: Nervous System Development > Vertebrates: Regional Development Nervous System Development > Vertebrates: General Principles.
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Affiliation(s)
- Yasushi Nakagawa
- Department of Neuroscience, University of Minnesota Medical School, Minneapolis, Minnesota
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21
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Guo Q, Li JYH. Defining developmental diversification of diencephalon neurons through single cell gene expression profiling. Development 2019; 146:dev.174284. [PMID: 30872278 DOI: 10.1242/dev.174284] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2018] [Accepted: 03/07/2019] [Indexed: 12/31/2022]
Abstract
The embryonic diencephalon forms integration centers and relay stations in the forebrain. Anecdotal expression studies suggest that the diencephalon contains multiple developmental compartments and subdivisions. Here, we utilized single cell RNA sequencing to profile transcriptomes of dissociated cells from the diencephalon of E12.5 mouse embryos. We identified the divergence of different progenitors, intermediate progenitors, and emerging neurons. By mapping the identified cell groups to their spatial origins, we characterized the molecular features of cell types and cell states arising from various diencephalic domains. Furthermore, we reconstructed the developmental trajectory of distinct cell lineages, and thereby identified the genetic cascades and gene regulatory networks underlying the progression of the cell cycle, neurogenesis and cellular diversification. The analysis provides new insights into the molecular mechanisms underlying the amplification of intermediate progenitor cells in the thalamus. The single cell-resolved trajectories not only confirm a close relationship between the rostral thalamus and prethalamus, but also uncover an unexpected close relationship between the caudal thalamus, epithalamus and rostral pretectum. Our data provide a useful resource for systematic studies of cell heterogeneity and differentiation kinetics within the diencephalon.
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Affiliation(s)
- Qiuxia Guo
- Department of Genetics and Genome Sciences, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT 06030-6403, USA
| | - James Y H Li
- Department of Genetics and Genome Sciences, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT 06030-6403, USA .,Institute for Systems Genomics, University of Connecticut, 400 Farmington Avenue, Farmington, CT 06030-6403, USA
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22
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Xiang Y, Tanaka Y, Cakir B, Patterson B, Kim KY, Sun P, Kang YJ, Zhong M, Liu X, Patra P, Lee SH, Weissman SM, Park IH. hESC-Derived Thalamic Organoids Form Reciprocal Projections When Fused with Cortical Organoids. Cell Stem Cell 2019; 24:487-497.e7. [PMID: 30799279 DOI: 10.1016/j.stem.2018.12.015] [Citation(s) in RCA: 263] [Impact Index Per Article: 52.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Revised: 10/01/2018] [Accepted: 12/20/2018] [Indexed: 12/22/2022]
Abstract
Human brain organoid techniques have rapidly advanced to facilitate investigating human brain development and diseases. These efforts have largely focused on generating telencephalon due to its direct relevance in a variety of forebrain disorders. Despite its importance as a relay hub between cortex and peripheral tissues, the investigation of three-dimensional (3D) organoid models for the human thalamus has not been explored. Here, we describe a method to differentiate human embryonic stem cells (hESCs) to thalamic organoids (hThOs) that specifically recapitulate the development of thalamus. Single-cell RNA sequencing revealed a formation of distinct thalamic lineages, which diverge from telencephalic fate. Importantly, we developed a 3D system to create the reciprocal projections between thalamus and cortex by fusing the two distinct region-specific organoids representing the developing thalamus or cortex. Our study provides a platform for understanding human thalamic development and modeling circuit organizations and related disorders in the brain.
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Affiliation(s)
- Yangfei Xiang
- Department of Genetics, Yale Stem Cell Center, Yale Child Study Center, Yale School of Medicine, New Haven, CT 06520, USA
| | - Yoshiaki Tanaka
- Department of Genetics, Yale Stem Cell Center, Yale Child Study Center, Yale School of Medicine, New Haven, CT 06520, USA
| | - Bilal Cakir
- Department of Genetics, Yale Stem Cell Center, Yale Child Study Center, Yale School of Medicine, New Haven, CT 06520, USA
| | - Benjamin Patterson
- Department of Genetics, Yale Stem Cell Center, Yale Child Study Center, Yale School of Medicine, New Haven, CT 06520, USA
| | - Kun-Yong Kim
- Department of Genetics, Yale Stem Cell Center, Yale Child Study Center, Yale School of Medicine, New Haven, CT 06520, USA
| | - Pingnan Sun
- Department of Genetics, Yale Stem Cell Center, Yale Child Study Center, Yale School of Medicine, New Haven, CT 06520, USA
| | - Young-Jin Kang
- Department of Neurology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Mei Zhong
- Department of Cell Biology, Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06520, USA
| | - Xinran Liu
- Department of Cell Biology, Center for Cellular and Molecular Imaging, Yale University School of Medicine, New Haven, CT 06511, USA
| | - Prabir Patra
- Department of Genetics, Yale Stem Cell Center, Yale Child Study Center, Yale School of Medicine, New Haven, CT 06520, USA; Department of Biomedical Engineering, University of Bridgeport, Bridgeport, CT 06604, USA
| | - Sang-Hun Lee
- Department of Neurology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Sherman M Weissman
- Department of Genetics, Yale Stem Cell Center, Yale Child Study Center, Yale School of Medicine, New Haven, CT 06520, USA
| | - In-Hyun Park
- Department of Genetics, Yale Stem Cell Center, Yale Child Study Center, Yale School of Medicine, New Haven, CT 06520, USA.
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Radial glia fibers translate Fgf8 morphogenetic signals to generate a thalamic nuclear complex protomap in the mantle layer. Brain Struct Funct 2018; 224:661-679. [PMID: 30470893 PMCID: PMC6420463 DOI: 10.1007/s00429-018-1794-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 11/09/2018] [Indexed: 01/25/2023]
Abstract
Thalamic neurons are distributed between different nuclear groups of the thalamic multinuclear complex; they develop topologically ordered specific projections that convey information on voluntary motor programs and sensory modalities to functional areas in the cerebral cortex. Since thalamic neurons present a homogeneous morphology, their functional specificity is derived from their afferent and efferent connectivity. Adequate development of thalamic afferent and efferent connections depends on guide signals that bind receptors in nuclear neuropils and axonal growth cones, respectively. These are finally regulated by regionalization processes in the thalamic neurons, codifying topological information. In this work, we studied the role of Fgf8 morphogenetic signaling in establishing the molecular thalamic protomap, which was revealed by Igsf21, Pde10a and Btbd3 gene expression in the thalamic mantle layer. Fgf8 signaling activity was evidenced by pERK expression in radial glia cells and fibers, which may represent a scaffold that translates neuroepithelial positional information to the mantle layer. In this work, we describe the fact that Fgf8-hypomorphic mice did not express pERK in radial glia cells and fibers and presented disorganized thalamic regionalization, increasing neuronal death in the ventro-lateral thalamus and strong disruption of thalamocortical projections. In conclusion, Fgf8 encodes the positional information required for thalamic nuclear regionalization and the development of thalamocortical projections.
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Abstract
The formation of the nervous system is a multistep process that yields a mature brain. Failure in any of the steps of this process may cause brain malfunction. In the early stages of embryonic development, neural progenitors quickly proliferate and then, at a specific moment, differentiate into neurons or glia. Once they become postmitotic neurons, they migrate to their final destinations and begin to extend their axons to connect with other neurons, sometimes located in quite distant regions, to establish different neural circuits. During the last decade, it has become evident that Zic genes, in addition to playing important roles in early development (e.g., gastrulation and neural tube closure), are involved in different processes of late brain development, such as neuronal migration, axon guidance, and refinement of axon terminals. ZIC proteins are therefore essential for the proper wiring and connectivity of the brain. In this chapter, we review our current knowledge of the role of Zic genes in the late stages of neural circuit formation.
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Roberson S, Halpern ME. Development and connectivity of the habenular nuclei. Semin Cell Dev Biol 2017; 78:107-115. [PMID: 29107475 PMCID: PMC5920772 DOI: 10.1016/j.semcdb.2017.10.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Accepted: 10/09/2017] [Indexed: 10/17/2022]
Abstract
Accumulating evidence has reinforced that the habenular region of the vertebrate dorsal forebrain is an essential integrating center, and a region strongly implicated in neurological disorders and addiction. Despite the important and diverse neuromodulatory roles the habenular nuclei play, their development has been understudied. The emphasis of this review is on the dorsal habenular nuclei of zebrafish, homologous to the medial nuclei of mammals, as recent work has revealed new information about the signaling pathways that regulate their formation. Additionally, the zebrafish dorsal habenulae have become a valuable model for probing how left-right differences are established in a vertebrate brain. Sonic hedgehog, fibroblast growth factors and Wingless-INT proteins are all involved in the generation of progenitor cells and ultimately, along with Notch signaling, influence habenular neurogenesis and left-right asymmetry. Intriguingly, a genetic network has emerged that leads to the differentiation of dorsal habenular neurons and, through localized chemokine signaling, directs the posterior outgrowth of their newly emerging axons towards their postsynaptic target, the midbrain interpeduncular nucleus.
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Affiliation(s)
- Sara Roberson
- Carnegie Institution for Science, Department of Embryology, 3520 San Martin Drive Baltimore, MD 21218, USA; Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA
| | - Marnie E Halpern
- Carnegie Institution for Science, Department of Embryology, 3520 San Martin Drive Baltimore, MD 21218, USA; Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA.
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Ontogenetic establishment of order-specific nuclear organization in the mammalian thalamus. Nat Neurosci 2017; 20:516-528. [PMID: 28250409 PMCID: PMC5374008 DOI: 10.1038/nn.4519] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2016] [Accepted: 01/25/2017] [Indexed: 12/11/2022]
Abstract
The thalamus connects the cortex with other brain regions and supports sensory perception, movement, and cognitive function via numerous distinct nuclei. However, the mechanisms underlying the development and organization of diverse thalamic nuclei remain largely unknown. Here we report an intricate ontogenetic logic of mouse thalamic structures. Individual radial glial progenitors in the developing thalamus actively divide and produce a cohort of neuronal progeny that shows striking spatial configuration and nuclear occupation related to functionality. Whereas the anterior clonal cluster displays relatively more tangential dispersion and contributes predominantly to nuclei with cognitive functions, the medial ventral posterior clonal cluster forms prominent radial arrays and contributes mostly to nuclei with sensory- or motor-related activities. Moreover, the first-order and higher-order sensory and motor nuclei across different modalities are largely segregated clonally. Notably, sonic hedgehog signaling activity influences clonal spatial distribution. Our study reveals lineage relationship to be a critical regulator of nonlaminated thalamus development and organization.
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Diencephalic Size Is Restricted by a Novel Interplay Between GCN5 Acetyltransferase Activity and Retinoic Acid Signaling. J Neurosci 2017; 37:2565-2579. [PMID: 28154153 DOI: 10.1523/jneurosci.2121-16.2017] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 01/24/2017] [Accepted: 01/25/2017] [Indexed: 01/20/2023] Open
Abstract
Diencephalic defects underlie an array of neurological diseases. Previous studies have suggested that retinoic acid (RA) signaling is involved in diencephalic development at late stages of embryonic development, but its roles and mechanisms of action during early neural development are still unclear. Here we demonstrate that mice lacking enzymatic activity of the acetyltransferase GCN5 ((Gcn5hat/hat )), which were previously characterized with respect to their exencephalic phenotype, exhibit significant diencephalic expansion, decreased diencephalic RA signaling, and increased diencephalic WNT and SHH signaling. Using a variety of molecular biology techniques in both cultured neuroepithelial cells treated with a GCN5 inhibitor and forebrain tissue from (Gcn5hat/hat ) embryos, we demonstrate that GCN5, RARα/γ, and the poorly characterized protein TACC1 form a complex in the nucleus that binds specific retinoic acid response elements in the absence of RA. Furthermore, RA triggers GCN5-mediated acetylation of TACC1, which results in dissociation of TACC1 from retinoic acid response elements and leads to transcriptional activation of RA target genes. Intriguingly, RA signaling defects caused by in vitro inhibition of GCN5 can be rescued through RA-dependent mechanisms that require RARβ. Last, we demonstrate that the diencephalic expansion and transcriptional defects seen in (Gcn5hat/hat ) mutants can be rescued with gestational RA supplementation, supporting a direct link between GCN5, TACC1, and RA signaling in the developing diencephalon. Together, our studies identify a novel, nonhistone substrate for GCN5 whose modification regulates a previously undescribed, tissue-specific mechanism of RA signaling that is required to restrict diencephalic size during early forebrain development.SIGNIFICANCE STATEMENT Changes in diencephalic size and shape, as well as SNPs associated with retinoic acid (RA) signaling-associated genes, have been linked to neuropsychiatric disorders. However, the mechanisms that regulate diencephalic morphogenesis and the involvement of RA signaling in this process are poorly understood. Here we demonstrate a novel role of the acetyltransferase GCN5 in a previously undescribed mechanism of RA signaling in the developing forebrain that is required to maintain the appropriate size of the diencephalon. Together, our experiments identify a novel nonhistone substrate of GCN5, highlight an essential role for both GCN5 and RA signaling in early diencephalic development, and elucidate a novel molecular regulatory mechanism for RA signaling that is specific to the developing forebrain.
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28
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Sena E, Feistel K, Durand BC. An Evolutionarily Conserved Network Mediates Development of the zona limitans intrathalamica, a Sonic Hedgehog-Secreting Caudal Forebrain Signaling Center. J Dev Biol 2016; 4:jdb4040031. [PMID: 29615594 PMCID: PMC5831802 DOI: 10.3390/jdb4040031] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2016] [Revised: 09/29/2016] [Accepted: 10/13/2016] [Indexed: 12/16/2022] Open
Abstract
Recent studies revealed new insights into the development of a unique caudal forebrain-signaling center: the zona limitans intrathalamica (zli). The zli is the last brain signaling center to form and the first forebrain compartment to be established. It is the only part of the dorsal neural tube expressing the morphogen Sonic Hedgehog (Shh) whose activity participates in the survival, growth and patterning of neuronal progenitor subpopulations within the thalamic complex. Here, we review the gene regulatory network of transcription factors and cis-regulatory elements that underlies formation of a shh-expressing delimitated domain in the anterior brain. We discuss evidence that this network predates the origin of chordates. We highlight the contribution of Shh, Wnt and Notch signaling to zli development and discuss implications for the fact that the morphogen Shh relies on primary cilia for signal transduction. The network that underlies zli development also contributes to thalamus induction, and to its patterning once the zli has been set up. We present an overview of the brain malformations possibly associated with developmental defects in this gene regulatory network (GRN).
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Affiliation(s)
- Elena Sena
- Institut Curie, Université Paris Sud, INSERM U1021, CNRS UMR3347, Centre Universitaire, Bâtiment 110, F-91405 Orsay Cedex, France.
| | - Kerstin Feistel
- Institute of Zoology, University of Hohenheim, Garbenstr. 30, 70593 Stuttgart, Germany.
| | - Béatrice C Durand
- Institut Curie, Université Paris Sud, INSERM U1021, CNRS UMR3347, Centre Universitaire, Bâtiment 110, F-91405 Orsay Cedex, France.
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29
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Zhang Y, Alvarez-Bolado G. Differential developmental strategies by Sonic hedgehog in thalamus and hypothalamus. J Chem Neuroanat 2016; 75:20-7. [DOI: 10.1016/j.jchemneu.2015.11.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 11/25/2015] [Indexed: 12/11/2022]
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30
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Nagalski A, Puelles L, Dabrowski M, Wegierski T, Kuznicki J, Wisniewska MB. Molecular anatomy of the thalamic complex and the underlying transcription factors. Brain Struct Funct 2016; 221:2493-510. [PMID: 25963709 PMCID: PMC4884203 DOI: 10.1007/s00429-015-1052-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Accepted: 04/27/2015] [Indexed: 01/19/2023]
Abstract
Thalamocortical loops have been implicated in the control of higher-order cognitive functions, but advances in our understanding of the molecular underpinnings of neocortical organization have not been accompanied by similar analyses in the thalamus. Using expression-based correlation maps and the manual mapping of mouse and human datasets available in the Allen Brain Atlas, we identified a few individual regions and several sets of molecularly related nuclei that partially overlap with the classic grouping that is based on topographical localization and thalamocortical connections. These new molecular divisions of the adult thalamic complex are defined by the combinatorial expression of Tcf7l2, Lef1, Gbx2, Prox1, Pou4f1, Esrrg, and Six3 transcription factor genes. Further in silico and experimental analyses provided the evidence that TCF7L2 might be a pan-thalamic specifier. These results provide substantial insights into the "molecular logic" that underlies organization of the thalamic complex.
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Affiliation(s)
- Andrzej Nagalski
- Laboratory of Neurodegeneration, International Institute of Molecular and Cell Biology, Warsaw, 02-109, Poland
- Laboratory of Molecular Neurobiology, Centre of New Technologies, University of Warsaw, Warsaw, 00-927, Poland
| | - Luis Puelles
- Department of Human Anatomy, University of Murcia and IMIB, Murcia, 30071, Spain
| | - Michal Dabrowski
- Laboratory of Bioinformatics, Center of Neurobiology, Nencki Institute of Experimental Biology, Warsaw, 02-093, Poland
| | - Tomasz Wegierski
- Laboratory of Neurodegeneration, International Institute of Molecular and Cell Biology, Warsaw, 02-109, Poland
| | - Jacek Kuznicki
- Laboratory of Neurodegeneration, International Institute of Molecular and Cell Biology, Warsaw, 02-109, Poland
| | - Marta B Wisniewska
- Laboratory of Neurodegeneration, International Institute of Molecular and Cell Biology, Warsaw, 02-109, Poland.
- Laboratory of Molecular Neurobiology, Centre of New Technologies, University of Warsaw, Warsaw, 00-927, Poland.
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31
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Feng J, Xian Q, Guan T, Hu J, Wang M, Huang Y, So KF, Evans SM, Chai G, Goffinet AM, Qu Y, Zhou L. Celsr3 and Fzd3 Organize a Pioneer Neuron Scaffold to Steer Growing Thalamocortical Axons. Cereb Cortex 2016; 26:3323-34. [PMID: 27170656 PMCID: PMC4898681 DOI: 10.1093/cercor/bhw132] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Celsr3 and Fzd3 regulate the development of reciprocal thalamocortical projections independently of their expression in cortical or thalamic neurons. To understand this cell non autonomous mechanism further, we tested whether Celsr3 and Fzd3 could act via Isl1-positive guidepost cells. Isl1-positive cells appear in the forebrain at embryonic day (E) 9.5-E10.5 and, from E12.5, they form 2 contingents in ventral telencephalon and prethalamus. In control mice, corticothalamic axons run in the ventral telencephalic corridor in close contact with Isl1-positive cells. When Celsr3 or Fzd3 is inactivated in Isl1-expressing cells, corticofugal fibers stall and loop in the ventral telencephalic corridor of high Isl1 expression, and thalamic axons fail to cross the diencephalon–telencephalon junction (DTJ). At E12.5, before thalamic and cortical axons emerge, pioneer projections from Isl1-positive cells cross the DTJ from both sides in control but not mutant embryos. These early projections appear to act like a bridge to guide later growing thalamic axons through the DTJ. Our data suggest that Celsr3 and Fzd3 orchestrate the formation of a scaffold of pioneer neurons and their axons. This scaffold extends from prethalamus to ventral telencephalon and subcortex, and steers reciprocal corticothalamic fibers.
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Affiliation(s)
- Jia Feng
- Guangdong-Hongkong-Macau Institute of CNS Regeneration, Ministry of Education CNS Regeneration Collaborative Joint Laboratory Guangdong key Laboratory of Brain Function and Diseases, Jinan University, Guangzhou 510632, PR China
| | - Quanxiang Xian
- Guangdong-Hongkong-Macau Institute of CNS Regeneration, Ministry of Education CNS Regeneration Collaborative Joint Laboratory Guangdong key Laboratory of Brain Function and Diseases, Jinan University, Guangzhou 510632, PR China
| | - Tingting Guan
- Guangdong-Hongkong-Macau Institute of CNS Regeneration, Ministry of Education CNS Regeneration Collaborative Joint Laboratory Guangdong key Laboratory of Brain Function and Diseases, Jinan University, Guangzhou 510632, PR China
| | - Jing Hu
- Guangdong-Hongkong-Macau Institute of CNS Regeneration, Ministry of Education CNS Regeneration Collaborative Joint Laboratory Guangdong key Laboratory of Brain Function and Diseases, Jinan University, Guangzhou 510632, PR China
| | - Meizhi Wang
- Guangdong-Hongkong-Macau Institute of CNS Regeneration, Ministry of Education CNS Regeneration Collaborative Joint Laboratory Guangdong key Laboratory of Brain Function and Diseases, Jinan University, Guangzhou 510632, PR China
| | - Yuhua Huang
- Guangdong-Hongkong-Macau Institute of CNS Regeneration, Ministry of Education CNS Regeneration Collaborative Joint Laboratory Guangdong key Laboratory of Brain Function and Diseases, Jinan University, Guangzhou 510632, PR China
| | - Kwok-Fai So
- Guangdong-Hongkong-Macau Institute of CNS Regeneration, Ministry of Education CNS Regeneration Collaborative Joint Laboratory Guangdong key Laboratory of Brain Function and Diseases, Jinan University, Guangzhou 510632, PR China Department of Anatomy, The University of Hong Kong Pokfulam, Hong Kong SAR, PR China
| | - Sylvia M Evans
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, CA 92093, USA
| | - Guoliang Chai
- Institute of Neuroscience, Université catholique de Louvain, Brussels B1200, Belgium
| | - Andre M Goffinet
- Institute of Neuroscience, Université catholique de Louvain, Brussels B1200, Belgium
| | - Yibo Qu
- Guangdong-Hongkong-Macau Institute of CNS Regeneration, Ministry of Education CNS Regeneration Collaborative Joint Laboratory Guangdong key Laboratory of Brain Function and Diseases, Jinan University, Guangzhou 510632, PR China Co-innovation Center of Neuroregeneration, Jiangsu, China
| | - Libing Zhou
- Guangdong-Hongkong-Macau Institute of CNS Regeneration, Ministry of Education CNS Regeneration Collaborative Joint Laboratory Guangdong key Laboratory of Brain Function and Diseases, Jinan University, Guangzhou 510632, PR China Co-innovation Center of Neuroregeneration, Jiangsu, China
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32
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Yao Y, Minor PJ, Zhao YT, Jeong Y, Pani AM, King AN, Symmons O, Gan L, Cardoso WV, Spitz F, Lowe CJ, Epstein DJ. Cis-regulatory architecture of a brain signaling center predates the origin of chordates. Nat Genet 2016; 48:575-80. [PMID: 27064252 PMCID: PMC4848136 DOI: 10.1038/ng.3542] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Accepted: 03/11/2016] [Indexed: 12/13/2022]
Abstract
Genomic approaches have predicted hundreds of thousands of tissue-specific cis-regulatory sequences, but the determinants critical to their function and evolutionary history are mostly unknown. Here we systematically decode a set of brain enhancers active in the zona limitans intrathalamica (zli), a signaling center essential for vertebrate forebrain development via the secreted morphogen Sonic hedgehog (Shh). We apply a de novo motif analysis tool to identify six position-independent sequence motifs together with their cognate transcription factors that are essential for zli enhancer activity and Shh expression in the mouse embryo. Using knowledge of this regulatory lexicon, we discover new Shh zli enhancers in mice and a functionally equivalent element in hemichordates, indicating an ancient origin of the Shh zli regulatory network that predates the chordate phylum. These findings support a strategy for delineating functionally conserved enhancers in the absence of overt sequence homologies and over extensive evolutionary distances.
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Affiliation(s)
- Yao Yao
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, 415 Curie Blvd, Clinical Research Building 470, Philadelphia, PA 19104, USA
| | - Paul J. Minor
- Hopkins Marine Station, Department of Biology, Stanford University, 120 Oceanview Blvd. Pacific Grove, CA 93950, USA
| | - Ying-Tao Zhao
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, 415 Curie Blvd, Clinical Research Building 470, Philadelphia, PA 19104, USA
| | - Yongsu Jeong
- Department of Genetic Engineering, College of Life Sciences and Graduate School of Biotechnology, Kyung Hee University, Yongin-si 446-701, Republic of Korea
| | - Ariel M. Pani
- Hopkins Marine Station, Department of Biology, Stanford University, 120 Oceanview Blvd. Pacific Grove, CA 93950, USA
| | - Anna N. King
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, 415 Curie Blvd, Clinical Research Building 470, Philadelphia, PA 19104, USA
| | - Orsolya Symmons
- Developmental Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Lin Gan
- Department of Ophthalmology, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Wellington V. Cardoso
- Columbia Center for Human Development, Department of Medicine, Pulmonary Allergy Critical Care, Columbia University Medical Center, New York, NY 10032, USA
| | - François Spitz
- Developmental Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Christopher J. Lowe
- Hopkins Marine Station, Department of Biology, Stanford University, 120 Oceanview Blvd. Pacific Grove, CA 93950, USA
| | - Douglas J. Epstein
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, 415 Curie Blvd, Clinical Research Building 470, Philadelphia, PA 19104, USA
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33
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Chen H, Uddin LQ, Zhang Y, Duan X, Chen H. Atypical effective connectivity of thalamo-cortical circuits in autism spectrum disorder. Autism Res 2016; 9:1183-1190. [PMID: 27868393 DOI: 10.1002/aur.1614] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Revised: 12/24/2015] [Accepted: 01/20/2016] [Indexed: 12/12/2022]
Abstract
Autism spectrum disorder (ASD) is a neurodevelopment disorder characterized by atypical connectivity within and across multiple brain systems. We aimed to explore information transmission from the sensory periphery to information processing centers of the brain across thalamo-cortical circuits in ASD. A large multicenter dataset from the autism brain imaging data exchange was utilized. A thalamus template derived from the Automatic Anatomic Labeling atlas was subdivided into six subregions corresponding to six cortical regions using a "winner-takes-all" strategy. Granger causality analysis (GCA) was then applied to calculate effective connectivity from subregions of the thalamus to the corresponding cortical regions. Results demonstrate reduced effective connectivity from the thalamus to left prefrontal cortex (P = 0.023), right posterior parietal cortex (P = 0.03), and bilateral temporal cortex (left: P = 0.014; right: P = 0.015) in ASD compared with healthy control (HC) participants. The GCA values of the thalamus-bilateral temporal cortex connections were significantly negatively correlated with communication scores as assessed by the autism diagnostic observation schedule in the ASD group (left: P = 0.037; right: P = 0.007). Age-related analyses showed that the strengths of the thalamus-bilateral temporal cortex connections were significantly positively correlated with age in the HC group (left: P = 0.013; right: P = 0.016), but not in the ASD group (left: P = 0.506; right: P = 0.219). These results demonstrate impaired thalamo-cortical information transmission in ASD and suggest that atypical development of thalamus-temporal cortex connections may relate to communication deficits in the disorder. Autism Res 2016, 9: 1183-1190. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.
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Affiliation(s)
- Heng Chen
- Key Laboratory for NeuroInformation of Ministry of Education, School of Life Science and Technology, and Center for Information in BioMedicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Lucina Q Uddin
- Department of Psychology, University of Miami, Coral Gables, FL, USA
| | - Youxue Zhang
- Key Laboratory for NeuroInformation of Ministry of Education, School of Life Science and Technology, and Center for Information in BioMedicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Xujun Duan
- Key Laboratory for NeuroInformation of Ministry of Education, School of Life Science and Technology, and Center for Information in BioMedicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Huafu Chen
- Key Laboratory for NeuroInformation of Ministry of Education, School of Life Science and Technology, and Center for Information in BioMedicine, University of Electronic Science and Technology of China, Chengdu, China
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Abstract
The neuroendocrine hypothalamus is composed of the tuberal and anterodorsal hypothalamus, together with the median eminence/neurohypophysis. It centrally governs wide-ranging physiological processes, including homeostasis of energy balance, circadian rhythms and stress responses, as well as growth and reproductive behaviours. Homeostasis is maintained by integrating sensory inputs and effecting responses via autonomic, endocrine and behavioural outputs, over diverse time-scales and throughout the lifecourse of an individual. Here, we summarize studies that begin to reveal how different territories and cell types within the neuroendocrine hypothalamus are assembled in an integrated manner to enable function, thus supporting the organism's ability to survive and thrive. We discuss how signaling pathways and transcription factors dictate the appearance and regionalization of the hypothalamic primordium, the maintenance of progenitor cells, and their specification and differentiation into neurons. We comment on recent studies that harness such programmes for the directed differentiation of human ES/iPS cells. We summarize how developmental plasticity is maintained even into adulthood and how integration between the hypothalamus and peripheral body is established in the median eminence and neurohypophysis. Analysis of model organisms, including mouse, chick and zebrafish, provides a picture of how complex, yet elegantly coordinated, developmental programmes build glial and neuronal cells around the third ventricle of the brain. Such conserved processes enable the hypothalamus to mediate its function as a central integrating and response-control mediator for the homeostatic processes that are critical to life. Early indications suggest that deregulation of these events may underlie multifaceted pathological conditions and dysfunctional physiology in humans, such as obesity.
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Affiliation(s)
- Sarah Burbridge
- Bateson Centre and Department of Biomedical Science, University of Sheffield, Sheffield, United Kingdom
| | - Iain Stewart
- Bateson Centre and Department of Biomedical Science, University of Sheffield, Sheffield, United Kingdom
| | - Marysia Placzek
- Bateson Centre and Department of Biomedical Science, University of Sheffield, Sheffield, United Kingdom
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35
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Durand BC. Stem cell-like Xenopus Embryonic Explants to Study Early Neural Developmental Features In Vitro and In Vivo. J Vis Exp 2016:e53474. [PMID: 26863402 DOI: 10.3791/53474] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Understanding the genetic programs underlying neural development is an important goal of developmental and stem cell biology. In the amphibian blastula, cells from the roof of the blastocoel are pluripotent. These cells can be isolated, and programmed to generate various tissues through manipulation of genes expression or induction by morphogens. In this manuscript protocols are described for the use of Xenopus laevis blastocoel roof explants as an assay system to investigate key in vivo and in vitro features of early neural development. These protocols allow the investigation of fate acquisition, cell migration behaviors, and cell autonomous and non-autonomous properties. The blastocoel roof explants can be cultured in a serum-free defined medium and grafted into host embryos. This transplantation into an embryo allows the investigation of the long-term lineage commitment, the inductive properties, and the behavior of transplanted cells in vivo. These assays can be exploited to investigate molecular mechanisms, cellular processes and gene regulatory networks underlying neural development. In the context of regenerative medicine, these assays provide a means to generate neural-derived cell types in vitro that could be used in drug screening.
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Affiliation(s)
- Beatrice C Durand
- Institut Curie; UMR 3387, CNRS; PSL Research University; Université Paris-Sud;
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36
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Clegg JM, Li Z, Molinek M, Caballero IM, Manuel MN, Price DJ. Pax6 is required intrinsically by thalamic progenitors for the normal molecular patterning of thalamic neurons but not the growth and guidance of their axons. Neural Dev 2015; 10:26. [PMID: 26520399 PMCID: PMC4628245 DOI: 10.1186/s13064-015-0053-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Accepted: 10/23/2015] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND In mouse embryos, the Pax6 transcription factor is expressed in the progenitors of thalamic neurons but not in thalamic neurons themselves. Its null-mutation causes early mis-patterning of thalamic progenitors. It is known that thalamic neurons generated by Pax6 (-/-) progenitors do not develop their normal connections with the cortex, but it is not clear why. We investigated the extent to which defects intrinsic to the thalamus are responsible. RESULTS We first confirmed that, in constitutive Pax6 (-/-) mutants, the axons of thalamic neurons fail to enter the telencephalon and, instead, many of them take an abnormal path to the hypothalamus, whose expression of Slits would normally repel them. We found that thalamic neurons show reduced expression of the Slit receptor Robo2 in Pax6 (-/-) mutants, which might enhance the ability of their axons to enter the hypothalamus. Remarkably, however, in chimeras comprising a mixture of Pax6 (-/-) and Pax6 (+/+) cells, Pax6 (-/-) thalamic neurons are able to generate axons that exit the diencephalon, take normal trajectories through the telencephalon and avoid the hypothalamus. This occurs despite abnormalities in their molecular patterning (they express Nkx2.2, unlike normal thalamic neurons) and their reduced expression of Robo2. In conditional mutants, acute deletion of Pax6 from the forebrain at the time when thalamic axons are starting to grow does not prevent the development of the thalamocortical tract, suggesting that earlier extra-thalamic patterning and /or morphological defects are the main cause of thalamocortical tract failure in Pax6 (-/-) constitutive mutants. CONCLUSIONS Our results indicate that Pax6 is required by thalamic progenitors for the normal molecular patterning of the thalamic neurons that they generate but thalamic neurons do not need normal Pax6-dependent patterning to become competent to grow axons that can be guided appropriately.
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Affiliation(s)
- James M Clegg
- Centre for Integrative Physiology, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK.
| | - Ziwen Li
- Centre for Integrative Physiology, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK.
| | - Michael Molinek
- Centre for Integrative Physiology, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK.
| | - Isabel Martín Caballero
- Centre for Integrative Physiology, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK.
- Current address: Laboratory of Molecular Neurobiology, Karolinska Institute, 17177, Scheeles Väg 1, Sweden.
| | - Martine N Manuel
- Centre for Integrative Physiology, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK.
| | - David J Price
- Centre for Integrative Physiology, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK.
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Wnt1 signal determines the patterning of the diencephalic dorso-ventral axis. Brain Struct Funct 2015; 221:3693-708. [PMID: 26452989 DOI: 10.1007/s00429-015-1126-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 09/30/2015] [Indexed: 12/31/2022]
Abstract
The diencephalon is a complex brain area that derives from the caudal region of the prosencephalon. This structure is divided into four longitudinal neuroepithelial zones: roof, alar, basal and floor plates, which constitute its dorso-ventral (DV) columnar domains. Morphogenetic differences between alar and basal plates in the prosencephalon and mesencephalon contribute to the characteristic expansion of alar plate derivatives in the brain and the formation of the cephalic flexure. Although differential histogenesis among DV regions seems to be relevant in understanding structural and functional complexity of the brain, most of our knowledge about DV regionalization comes from the spinal cord development. Therefore, it seems of interest to study the molecular mechanisms that govern DV patterning in the diencephalon, the brain region where strong differences in size and complexity between alar and basal derivatives are evident in all vertebrates. Different morphogenetic signals, which induce specific progenitors fate to the neighboring epithelium, are involved in the spinal cord DV patterning. To study if Wnt1, one of these signaling molecules, has a role for the establishment of the diencephalic longitudinal domains, we carried out gain- and loss-of-function experiments, using mice and chick embryos. Our results demonstrated functional differences in the molecular mechanisms downstream of Wnt1 function in the diencephalon, in relation to the spinal cord. We further demonstrated that Bmp4 signal induces Wnt1 expression in the diencephalon, unraveling a new molecular regulatory code downstream of primary dorsalizing signals to control ventral regionalization in the diencephalon.
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Mallika C, Guo Q, Li JYH. Gbx2 is essential for maintaining thalamic neuron identity and repressing habenular characters in the developing thalamus. Dev Biol 2015; 407:26-39. [PMID: 26297811 DOI: 10.1016/j.ydbio.2015.08.010] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Revised: 08/10/2015] [Accepted: 08/12/2015] [Indexed: 12/30/2022]
Abstract
The thalamus and habenula, two important nodes of the forebrain circuitry, are derived from a single developmental compartment, called prosomere 2, in the diencephalon. Habenular and thalamic neurons display distinct molecular identity, neurochemistry, and connectivity. Furthermore, their progenitors exhibit distinctive neurogenic patterns with a marked delay in the onset of neurogenesis in the thalamus. However, the progenitors in prosomere 2 express many common developmental regulators and the mechanism underlying the specification and differentiation of these two populations of neurons remains unknown. Gbx2, coding for a homeodomain transcription factor, is initially expressed in thalamic neuronal precursors that have just exited the cell cycle, and its expression is maintained in many mature thalamic neurons in adults. Deletion of Gbx2 severely disrupts histogenesis of the thalamus and abolishes thalamocortical projections in mice. Here, by using genome-wide transcriptional profiling, we show that Gbx2 promotes thalamic but inhibits habenular molecular characters. Remarkably, although Gbx2 is expressed in postmitotic neuronal precursors, deletion of Gbx2 changes gene expression and cell proliferation in dividing progenitors in the developing thalamus. These defects are partially rescued by the mosaic presence of wild-type cells, demonstrating a cell non-autonomous role of Gbx2 in regulating the development of thalamic progenitors. Our results suggest that Gbx2 is essential for the acquisition of the thalamic neuronal identity by repressing habenular identity through a feedback signaling from postmitotic neurons to progenitors.
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Affiliation(s)
- Chatterjee Mallika
- Department of Genetics and Genome Sciences, University of Connecticut School of Medicine, 400 Farmington Avenue, Farmington, CT 06030-6403, United States
| | - Qiuxia Guo
- Department of Genetics and Genome Sciences, University of Connecticut School of Medicine, 400 Farmington Avenue, Farmington, CT 06030-6403, United States
| | - James Y H Li
- Department of Genetics and Genome Sciences, University of Connecticut School of Medicine, 400 Farmington Avenue, Farmington, CT 06030-6403, United States.
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Heide M, Zhang Y, Zhou X, Zhao T, Miquelajáuregui A, Varela-Echavarría A, Alvarez-Bolado G. Lhx5 controls mamillary differentiation in the developing hypothalamus of the mouse. Front Neuroanat 2015; 9:113. [PMID: 26321924 PMCID: PMC4536661 DOI: 10.3389/fnana.2015.00113] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 07/30/2015] [Indexed: 12/30/2022] Open
Abstract
Acquisition of specific neuronal identity by individual brain nuclei is a key step in brain development. However, how the mechanisms that confer neuronal identity are integrated with upstream regional specification networks is still mysterious. Expression of Sonic hedgehog (Shh), is required for hypothalamic specification and is later downregulated by Tbx3 to allow for the differentiation of the tubero-mamillary region. In this region, the mamillary body (MBO), is a large neuronal aggregate essential for memory formation. To clarify how MBO identity is acquired after regional specification, we investigated Lhx5, a transcription factor with restricted MBO expression. We first generated a hypomorph allele of Lhx5—in homozygotes, the MBO disappears after initial specification. Intriguingly, in these mutants, Tbx3 was downregulated and the Shh expression domain abnormally extended. Microarray analysis and chromatin immunoprecipitation indicated that Lhx5 appears to be involved in Shh downregulation through Tbx3 and activates several MBO-specific regulator and effector genes. Finally, by tracing the caudal hypothalamic cell lineage we show that, in the Lhx5 mutant, at least some MBO cells are present but lack characteristic marker expression. Our work shows how the Lhx5 locus contributes to integrate regional specification pathways with downstream acquisition of neuronal identity in the MBO.
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Affiliation(s)
- Michael Heide
- Institute of Anatomy and Cell Biology, University of Heidelberg Heidelberg, Germany
| | - Yuanfeng Zhang
- Institute of Anatomy and Cell Biology, University of Heidelberg Heidelberg, Germany
| | - Xunlei Zhou
- Institute of Anatomy and Cell Biology, University of Heidelberg Heidelberg, Germany
| | - Tianyu Zhao
- Key Laboratory of Oral Disease and Biomedical Sciences, Stomatological Hospital, Chongqing Medical University Chongqing, China
| | - Amaya Miquelajáuregui
- Departamento de Neurobiología del Desarrollo y Neurofisiología, Instituto de Neurobiología, Universidad Nacional Autónoma de México Querétaro, Mexico
| | - Alfredo Varela-Echavarría
- Departamento de Neurobiología del Desarrollo y Neurofisiología, Instituto de Neurobiología, Universidad Nacional Autónoma de México Querétaro, Mexico
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Bandín S, Morona R, González A. Prepatterning and patterning of the thalamus along embryonic development of Xenopus laevis. Front Neuroanat 2015; 9:107. [PMID: 26321920 PMCID: PMC4530589 DOI: 10.3389/fnana.2015.00107] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 07/24/2015] [Indexed: 01/18/2023] Open
Abstract
Previous developmental studies of the thalamus (alar part of the diencephalic prosomere p2) have defined the molecular basis for the acquisition of the thalamic competence (preparttening), the subsequent formation of the secondary organizer in the zona limitans intrathalamica, and the early specification of two anteroposterior domains (rostral and caudal progenitor domains) in response to inducing activities and that are shared in birds and mammals. In the present study we have analyzed the embryonic development of the thalamus in the anuran Xenopus laevis to determine conserved or specific features in the amphibian diencephalon. From early embryonic stages to the beginning of the larval period, the expression patterns of 22 markers were analyzed by means of combined In situ hybridization (ISH) and immunohistochemical techniques. The early genoarchitecture observed in the diencephalon allowed us to discern the boundaries of the thalamus with the prethalamus, pretectum, and epithalamus. Common molecular features were observed in the thalamic prepatterning among vertebrates in which Wnt3a, Fez, Pax6 and Xiro1 expression were of particular importance in Xenopus. The formation of the zona limitans intrathalamica was observed, as in other vertebrates, by the progressive expression of Shh. The largely conserved expressions of Nkx2.2 in the rostral thalamic domain vs. Gbx2 and Ngn2 (among others) in the caudal domain strongly suggest the role of Shh as morphogen in the amphibian thalamus. All these data showed that the molecular characteristics observed during preparttening and patterning in the thalamus of the anuran Xenopus (anamniote) share many features with those described during thalamic development in amniotes (common patterns in tetrapods) but also with zebrafish, strengthening the idea of a basic organization of this diencephalic region across vertebrates.
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Affiliation(s)
- Sandra Bandín
- Faculty of Biology, Department of Cell Biology, University Complutense Madrid, Spain
| | - Ruth Morona
- Faculty of Biology, Department of Cell Biology, University Complutense Madrid, Spain
| | - Agustín González
- Faculty of Biology, Department of Cell Biology, University Complutense Madrid, Spain
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Klarić T, Lardelli M, Key B, Koblar S, Lewis M. Activity-dependent expression of neuronal PAS domain-containing protein 4 (npas4a) in the developing zebrafish brain. Front Neuroanat 2014; 8:148. [PMID: 25538572 PMCID: PMC4255624 DOI: 10.3389/fnana.2014.00148] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Accepted: 11/18/2014] [Indexed: 11/26/2022] Open
Abstract
In rodents, the Npas4 gene has recently been identified as being an important regulator of synaptic plasticity and memory. Homologs of Npas4 have been found in invertebrate species though their functions appear to be too divergent for them to be studied as a proxy for the mammalian proteins. The aim of this study, therefore, was to ascertain the suitability of the zebrafish as a model organism for investigating the function of Npas4 genes. We show here that the expression and regulation of the zebrafish Npas4 homolog, npas4a, is remarkably similar to that of the rodent Npas4 genes. As in mammals, expression of the zebrafish npas4a gene is restricted to the brain where it is up-regulated in response to neuronal activity. Furthermore, we also show that knockdown of npas4a during embryonic development results in a number of forebrain-specific defects including increased apoptosis and misexpression of the forebrain marker genes dlx1a and shha. Our work demonstrates that the zebrafish is a suitable model organism for investigating the role of the npas4a gene and one that is likely to provide valuable insights into the function of the mammalian homologs. Furthermore, our findings highlight a potential role for npas4a in forebrain development.
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Affiliation(s)
- Thomas Klarić
- School of Molecular and Biomedical Sciences, The University of Adelaide Adelaide, SA, Australia
| | - Michael Lardelli
- School of Molecular and Biomedical Sciences, The University of Adelaide Adelaide, SA, Australia
| | - Brian Key
- School of Biomedical Sciences, The University of Queensland Brisbane, QLD, Australia
| | - Simon Koblar
- School of Medicine, The University of Adelaide Adelaide, SA, Australia
| | - Martin Lewis
- School of Molecular and Biomedical Sciences, The University of Adelaide Adelaide, SA, Australia
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Leivada E, Boeckx C. Schizophrenia and cortical blindness: protective effects and implications for language. Front Hum Neurosci 2014; 8:940. [PMID: 25506321 PMCID: PMC4246684 DOI: 10.3389/fnhum.2014.00940] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Accepted: 11/04/2014] [Indexed: 01/20/2023] Open
Abstract
The repeatedly noted absence of case-reports of individuals with schizophrenia and congenital/early developed blindness has led several authors to argue that the latter can confer protective effects against the former. In this work, we present a number of relevant case-reports from different syndromes that show comorbidity of congenital and early blindness with schizophrenia. On the basis of these reports, we argue that a distinction between different types of blindness in terms of the origin of the visual deficit, cortical or peripheral, is crucial for understanding the observed patterns of comorbidity. We discuss the genetic underpinnings and the brain structures involved in schizophrenia and blindness, with insights from language processing, laying emphasis on the three structures that particularly stand out: the occipital cortex, the lateral geniculate nucleus (LGN), and the pulvinar. Last, we build on previous literature on the nature of the protective effects in order to offer novel insights into the nature of the protection mechanism from the perspective of the brain structures involved in each type of blindness.
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Affiliation(s)
- Evelina Leivada
- Department of Linguistics, Universitat de BarcelonaBarcelona, Spain
| | - Cedric Boeckx
- Department of Linguistics, Universitat de BarcelonaBarcelona, Spain
- Catalan Institute for Advanced Studies and Research (ICREA)Barcelona, Spain
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Boeckx C, Benítez-Burraco A. Globularity and language-readiness: generating new predictions by expanding the set of genes of interest. Front Psychol 2014; 5:1324. [PMID: 25505436 PMCID: PMC4243498 DOI: 10.3389/fpsyg.2014.01324] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Accepted: 10/31/2014] [Indexed: 12/30/2022] Open
Abstract
This study builds on the hypothesis put forth in Boeckx and Benítez-Burraco (2014), according to which the developmental changes expressed at the levels of brain morphology and neural connectivity that resulted in a more globular braincase in our species were crucial to understand the origins of our language-ready brain. Specifically, this paper explores the links between two well-known 'language-related' genes like FOXP2 and ROBO1 implicated in vocal learning and the initial set of genes of interest put forth in Boeckx and Benítez-Burraco (2014), with RUNX2 as focal point. Relying on the existing literature, we uncover potential molecular links that could be of interest to future experimental inquiries into the biological foundations of language and the testing of our initial hypothesis. Our discussion could also be relevant for clinical linguistics and for the interpretation of results from paleogenomics.
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Affiliation(s)
- Cedric Boeckx
- Catalan Institute for Advanced Studies and Research (ICREA)Barcelona, Spain
- Department of Linguistics, Universitat de BarcelonaBarcelona, Spain
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Juraver-Geslin HA, Gómez-Skarmeta JL, Durand BC. The conserved barH-like homeobox-2 gene barhl2 acts downstream of orthodentricle-2 and together with iroquois-3 in establishment of the caudal forebrain signaling center induced by Sonic Hedgehog. Dev Biol 2014; 396:107-20. [PMID: 25281935 DOI: 10.1016/j.ydbio.2014.09.027] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 08/13/2014] [Accepted: 09/23/2014] [Indexed: 01/01/2023]
Abstract
In this study, we investigated the gene regulatory network that governs formation of the Zona limitans intrathalamica (ZLI), a signaling center that secretes Sonic Hedgehog (Shh) to control the growth and regionalization of the caudal forebrain. Using loss- and gain-of-function, explants and grafting experiments in amphibians, we demonstrate that barhl2 acts downstream of otx2 and together with the iroquois (irx)-3 gene in establishment of the ZLI compartment initiated by Shh influence. We find that the presumptive (pre)-ZLI domain expresses barhl2, otx2 and irx3, whereas the thalamus territory caudally bordering the pre-ZLI expresses barhl2, otx2 and irx1/2 and early on irx3. We demonstrate that Barhl2 activity is required for determination of the ZLI and thalamus fates and that within the p2 alar plate the ratio of Irx3 to Irx1/2 contributes to ZLI specification and size determination. We show that when continuously exposed to Shh, neuroepithelial cells coexpressing barhl2, otx2 and irx3 acquire two characteristics of the ZLI compartment-the competence to express shh and the ability to segregate from anterior neural plate cells. In contrast, neuroepithelial cells expressing barhl2, otx2 and irx1/2, are not competent to express shh. Noteworthy in explants, under Shh influence, ZLI-like cells segregate from thalamic-like cells. Our study establishes that Barhl2 activity plays a key role in p2 alar plate patterning, specifically ZLI formation, and provides new insights on establishment of the signaling center of the caudal forebrain.
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Affiliation(s)
- Hugo A Juraver-Geslin
- Ecole Normale Supérieure, Institut de Biologie de l'ENS, IBENS, S1.7 46 rue d'Ulm 75005, Paris F-75005, France; INSERM, U1024, Paris F-75005, France; CNRS, UMR 8197, Paris F-75005, France; S1.7 46 rue d'Ulm, 75005 Paris, France
| | - José Luis Gómez-Skarmeta
- Centro Andaluz de Biología del Desarrollo-CSIC/Universidad Pablo de Olavide, Carretera de Utrera, Km1, 41013 Sevilla, Spain
| | - Béatrice C Durand
- Ecole Normale Supérieure, Institut de Biologie de l'ENS, IBENS, S1.7 46 rue d'Ulm 75005, Paris F-75005, France; INSERM, U1024, Paris F-75005, France; CNRS, UMR 8197, Paris F-75005, France; S1.7 46 rue d'Ulm, 75005 Paris, France.
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45
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Caballero IM, Manuel MN, Molinek M, Quintana-Urzainqui I, Mi D, Shimogori T, Price DJ. Cell-autonomous repression of Shh by transcription factor Pax6 regulates diencephalic patterning by controlling the central diencephalic organizer. Cell Rep 2014; 8:1405-18. [PMID: 25176648 PMCID: PMC4241467 DOI: 10.1016/j.celrep.2014.07.051] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Revised: 06/24/2014] [Accepted: 07/27/2014] [Indexed: 11/17/2022] Open
Abstract
During development, region-specific patterns of regulatory gene expression are controlled by signaling centers that release morphogens providing positional information to surrounding cells. Regulation of signaling centers themselves is therefore critical. The size and the influence of a Shh-producing forebrain organizer, the zona limitans intrathalamica (ZLI), are limited by Pax6. By studying mouse chimeras, we find that Pax6 acts cell autonomously to block Shh expression in cells around the ZLI. Immunoprecipitation and luciferase assays indicate that Pax6 can bind the Shh promoter and repress its function. An analysis of chimeras suggests that many of the regional gene expression pattern defects that occur in Pax6−/− diencephalic cells result from a non-cell-autonomous position-dependent defect of local intercellular signaling. Blocking Shh signaling in Pax6−/− mutants reverses major diencephalic patterning defects. We conclude that Pax6’s cell-autonomous repression of Shh expression around the ZLI is critical for many aspects of normal diencephalic patterning. Pax6 limits the effects of a forebrain organizer, the zona limitans intrathalamica Pax6 blocks diencephalic Shh expression cell autonomously Absence of Pax6 causes non-cell-autonomous diencephalic patterning defects Blocking Shh signaling in Pax6−/− mutants reverses diencephalic patterning defects
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Affiliation(s)
| | - Martine N Manuel
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh EH8 9XD, UK
| | - Michael Molinek
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh EH8 9XD, UK
| | | | - Da Mi
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh EH8 9XD, UK
| | | | - David J Price
- Centre for Integrative Physiology, University of Edinburgh, Edinburgh EH8 9XD, UK.
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Genetic evidence that Celsr3 and Celsr2, together with Fzd3, regulate forebrain wiring in a Vangl-independent manner. Proc Natl Acad Sci U S A 2014; 111:E2996-3004. [PMID: 25002511 DOI: 10.1073/pnas.1402105111] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Celsr3 and Fzd3, members of "core planar cell polarity" (PCP) genes, were shown previously to control forebrain axon guidance and wiring by acting in axons and/or guidepost cells. Here, we show that Celsr2 acts redundantly with Celsr3, and that their combined mutation mimics that of Fzd3. The phenotypes generated upon inactivation of Fzd3 in different forebrain compartments are similar to those in conditional Celsr2-3 mutants, indicating that Fzd3 and Celsr2-3 act in the same population of cells. Inactivation of Celsr2-3 or Fzd3 in thalamus does not affect forebrain wiring, and joint inactivation in cortex and thalamus adds little to cortical inactivation alone in terms of thalamocortical projections. On the other hand, joint inactivation perturbs strongly the formation of the barrel field, which is unaffected upon single cortical or thalamic inactivation, indicating a role for interactions between thalamic axons and cortical neurons in cortical arealization. Unexpectedly, forebrain wiring is normal in mice defective in Vangl1 and Vangl2, showing that, contrary to epithelial PCP, axon guidance can be Vangl independent in some contexts. Our results suggest that Celsr2-3 and Fzd3 regulate axonal navigation in the forebrain by using mechanisms different from classical epithelial PCP, and require interacting partners other than Vangl1-2 that remain to be identified.
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47
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Eckler MJ, Chen B. Fez family transcription factors: controlling neurogenesis and cell fate in the developing mammalian nervous system. Bioessays 2014; 36:788-97. [PMID: 24913420 DOI: 10.1002/bies.201400039] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Fezf1 and Fezf2 are highly conserved transcription factors that were first identified by their specific expression in the anterior neuroepithelium of Xenopus and zebrafish embryos. These proteins share an N-terminal domain with homology to the canonical engrailed repressor motif and a C-terminal DNA binding domain containing six C2H2 zinc-finger repeats. Over a decade of study indicates that the Fez proteins play critical roles during nervous system development in species as diverse as fruit flies and mice. Herein we discuss recent progress in understanding the functions of Fezf1 and Fezf2 in neurogenesis and cell fate specification during mammalian nervous system development. Going forward we believe that efforts should focus on understanding how expression of these factors is precisely regulated, and on identifying target DNA sequences and interacting partners. Such knowledge may reveal the mechanisms by which Fezf1 and Fezf2 accomplish both independent and redundant functions across diverse tissue and cell types.
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Affiliation(s)
- Matthew J Eckler
- Department of Molecular, Cell and Developmental Biology, University of California, Santa Cruz, CA, USA
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48
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Golding B, Pouchelon G, Bellone C, Murthy S, Di Nardo AA, Govindan S, Ogawa M, Shimogori T, Lüscher C, Dayer A, Jabaudon D. Retinal input directs the recruitment of inhibitory interneurons into thalamic visual circuits. Neuron 2014; 81:1057-1069. [PMID: 24607228 DOI: 10.1016/j.neuron.2014.01.032] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/13/2014] [Indexed: 10/25/2022]
Abstract
Inhibitory interneurons (INs) critically control the excitability and plasticity of neuronal networks, but whether activity can direct INs into specific circuits during development is unknown. Here, we report that in the dorsal lateral geniculate nucleus (dLGN), which relays retinal input to the cortex, circuit activity is required for the migration, molecular differentiation, and functional integration of INs. We first characterize the prenatal origin and molecular identity of dLGN INs, revealing their recruitment from an Otx2(+) neuronal pool located in the adjacent ventral LGN. Using time-lapse and electrophysiological recordings, together with genetic and pharmacological perturbation of retinal waves, we show that retinal activity directs the navigation and circuit incorporation of dLGN INs during the first postnatal week, thereby regulating the inhibition of thalamocortical circuits. These findings identify an input-dependent mechanism regulating IN migration and circuit inhibition, which may account for the progressive recruitment of INs into expanding excitatory circuits during evolution.
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Affiliation(s)
- Bruno Golding
- Department of Basic Neurosciences, University of Geneva, 1 Rue Michel Servet, 1211 Geneva, Switzerland
| | - Gabrielle Pouchelon
- Department of Basic Neurosciences, University of Geneva, 1 Rue Michel Servet, 1211 Geneva, Switzerland
| | - Camilla Bellone
- Department of Basic Neurosciences, University of Geneva, 1 Rue Michel Servet, 1211 Geneva, Switzerland
| | - Sahana Murthy
- Department of Basic Neurosciences, University of Geneva, 1 Rue Michel Servet, 1211 Geneva, Switzerland
| | - Ariel A Di Nardo
- Center for Interdisciplinary Research in Biology, UMR CNRS 7241/INSERM U1050, Collège de France, 11 Place Marcelin Berthelot, 75005 Paris, France
| | - Subashika Govindan
- Department of Basic Neurosciences, University of Geneva, 1 Rue Michel Servet, 1211 Geneva, Switzerland
| | - Masahuro Ogawa
- Riken Brain Science Institute, 2-1 Hirosawa Wako City, Saitama 351-0198, Japan
| | - Tomomi Shimogori
- Riken Brain Science Institute, 2-1 Hirosawa Wako City, Saitama 351-0198, Japan
| | - Christian Lüscher
- Department of Basic Neurosciences, University of Geneva, 1 Rue Michel Servet, 1211 Geneva, Switzerland; Department of Neurology, Geneva University Hospital, 4 Rue Gabrielle-Perret-Gentil, 1205 Geneva, Switzerland
| | - Alexandre Dayer
- Department of Basic Neurosciences, University of Geneva, 1 Rue Michel Servet, 1211 Geneva, Switzerland; Department of Psychiatry, Geneva University Hospital, 4 Rue Gabrielle-Perret-Gentil, 1205 Geneva, Switzerland
| | - Denis Jabaudon
- Department of Basic Neurosciences, University of Geneva, 1 Rue Michel Servet, 1211 Geneva, Switzerland; Department of Neurology, Geneva University Hospital, 4 Rue Gabrielle-Perret-Gentil, 1205 Geneva, Switzerland.
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Boeckx C, Benítez-Burraco A. The shape of the human language-ready brain. Front Psychol 2014; 5:282. [PMID: 24772099 PMCID: PMC3983487 DOI: 10.3389/fpsyg.2014.00282] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Accepted: 03/17/2014] [Indexed: 12/14/2022] Open
Abstract
Our core hypothesis is that the emergence of our species-specific language-ready brain ought to be understood in light of the developmental changes expressed at the levels of brain morphology and neural connectivity that occurred in our species after the split from Neanderthals–Denisovans and that gave us a more globular braincase configuration. In addition to changes at the cortical level, we hypothesize that the anatomical shift that led to globularity also entailed significant changes at the subcortical level. We claim that the functional consequences of such changes must also be taken into account to gain a fuller understanding of our linguistic capacity. Here we focus on the thalamus, which we argue is central to language and human cognition, as it modulates fronto-parietal activity. With this new neurobiological perspective in place, we examine its possible molecular basis. We construct a candidate gene set whose members are involved in the development and connectivity of the thalamus, in the evolution of the human head, and are known to give rise to language-associated cognitive disorders. We submit that the new gene candidate set opens up new windows into our understanding of the genetic basis of our linguistic capacity. Thus, our hypothesis aims at generating new testing grounds concerning core aspects of language ontogeny and phylogeny.
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Affiliation(s)
- Cedric Boeckx
- Catalan Institute for Advanced Studies and Research (ICREA) Barcelona, Spain ; Department of Linguistics, Universitat de Barcelona Barcelona, Spain
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Achim K, Salminen M, Partanen J. Mechanisms regulating GABAergic neuron development. Cell Mol Life Sci 2014; 71:1395-415. [PMID: 24196748 PMCID: PMC11113277 DOI: 10.1007/s00018-013-1501-3] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Revised: 10/10/2013] [Accepted: 10/14/2013] [Indexed: 12/17/2022]
Abstract
Neurons using gamma-aminobutyric acid (GABA) as their neurotransmitter are the main inhibitory neurons in the mature central nervous system (CNS) and show great variation in their form and function. GABAergic neurons are produced in all of the main domains of the CNS, where they develop from discrete regions of the neuroepithelium. Here, we review the gene expression and regulatory mechanisms controlling the main steps of GABAergic neuron development: early patterning of the proliferative neuroepithelium, production of postmitotic neural precursors, establishment of their identity and migration. By comparing the molecular regulation of these events across CNS, we broadly identify three regions utilizing distinct molecular toolkits for GABAergic fate determination: telencephalon-anterior diencephalon (DLX2 type), posterior diencephalon-midbrain (GATA2 type) and hindbrain-spinal cord (PTF1A and TAL1 types). Similarities and differences in the molecular regulatory mechanisms reveal the core determinants of a GABAergic neuron as well as provide insights into generation of the vast diversity of these neurons.
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Affiliation(s)
- Kaia Achim
- EMBL Heidelberg, Meyerhofstr. 1, 69117 Heidelberg, Germany
| | - Marjo Salminen
- Department of Veterinary Biosciences, University of Helsinki, Agnes Sjobergin katu 2, PO Box 66, 00014 Helsinki, Finland
| | - Juha Partanen
- Department of Biosciences, University of Helsinki, Viikinkaari 5, PO Box 56, 00014 Helsinki, Finland
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