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Schilling K. Revisiting the development of cerebellar inhibitory interneurons in the light of single-cell genetic analyses. Histochem Cell Biol 2024; 161:5-27. [PMID: 37940705 PMCID: PMC10794478 DOI: 10.1007/s00418-023-02251-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/12/2023] [Indexed: 11/10/2023]
Abstract
The present review aims to provide a short update of our understanding of the inhibitory interneurons of the cerebellum. While these cells constitute but a minority of all cerebellar neurons, their functional significance is increasingly being recognized. For one, inhibitory interneurons of the cerebellar cortex are now known to constitute a clearly more diverse group than their traditional grouping as stellate, basket, and Golgi cells suggests, and this diversity is now substantiated by single-cell genetic data. The past decade or so has also provided important information about interneurons in cerebellar nuclei. Significantly, developmental studies have revealed that the specification and formation of cerebellar inhibitory interneurons fundamentally differ from, say, the cortical interneurons, and define a mode of diversification critically dependent on spatiotemporally patterned external signals. Last, but not least, in the past years, dysfunction of cerebellar inhibitory interneurons could also be linked with clinically defined deficits. I hope that this review, however fragmentary, may stimulate interest and help focus research towards understanding the cerebellum.
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Affiliation(s)
- Karl Schilling
- Anatomisches Institut - Anatomie und Zellbiologie, Rheinische Friedrich-Wilhelms-Universität Bonn, Nussallee 10, 53115, Bonn, Germany.
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2
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Aceves M, Tucker A, Chen J, Vo K, Moses J, Amar Kumar P, Thomas H, Miranda D, Dampf G, Dietz V, Chang M, Lukose A, Jang J, Nadella S, Gillespie T, Trevino C, Buxton A, Pritchard AL, Green P, McCreedy DA, Dulin JN. Developmental stage of transplanted neural progenitor cells influences anatomical and functional outcomes after spinal cord injury in mice. Commun Biol 2023; 6:544. [PMID: 37208439 PMCID: PMC10199026 DOI: 10.1038/s42003-023-04893-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 05/02/2023] [Indexed: 05/21/2023] Open
Abstract
Neural progenitor cell (NPC) transplantation is a promising therapeutic strategy for replacing lost neurons following spinal cord injury (SCI). However, how graft cellular composition influences regeneration and synaptogenesis of host axon populations, or recovery of motor and sensory functions after SCI, is poorly understood. We transplanted developmentally-restricted spinal cord NPCs, isolated from E11.5-E13.5 mouse embryos, into sites of adult mouse SCI and analyzed graft axon outgrowth, cellular composition, host axon regeneration, and behavior. Earlier-stage grafts exhibited greater axon outgrowth, enrichment for ventral spinal cord interneurons and Group-Z spinal interneurons, and enhanced host 5-HT+ axon regeneration. Later-stage grafts were enriched for late-born dorsal horn interneuronal subtypes and Group-N spinal interneurons, supported more extensive host CGRP+ axon ingrowth, and exacerbated thermal hypersensitivity. Locomotor function was not affected by any type of NPC graft. These findings showcase the role of spinal cord graft cellular composition in determining anatomical and functional outcomes following SCI.
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Affiliation(s)
- Miriam Aceves
- Department of Biology, Texas A&M University, College Station, TX, 77843, USA
- Texas A&M Institute for Neuroscience, Texas A&M University, College Station, TX, 77843, USA
| | - Ashley Tucker
- Department of Biology, Texas A&M University, College Station, TX, 77843, USA
- Texas A&M Institute for Neuroscience, Texas A&M University, College Station, TX, 77843, USA
| | - Joseph Chen
- Department of Biology, Texas A&M University, College Station, TX, 77843, USA
| | - Katie Vo
- Department of Biology, Texas A&M University, College Station, TX, 77843, USA
| | - Joshua Moses
- Department of Biology, Texas A&M University, College Station, TX, 77843, USA
| | | | - Hannah Thomas
- Department of Biology, Texas A&M University, College Station, TX, 77843, USA
| | - Diego Miranda
- Department of Biology, Texas A&M University, College Station, TX, 77843, USA
| | - Gabrielle Dampf
- Department of Biology, Texas A&M University, College Station, TX, 77843, USA
| | - Valerie Dietz
- Department of Biology, Texas A&M University, College Station, TX, 77843, USA
| | - Matthew Chang
- Department of Biology, Texas A&M University, College Station, TX, 77843, USA
| | - Aleena Lukose
- Department of Biology, Texas A&M University, College Station, TX, 77843, USA
| | - Julius Jang
- Department of Biology, Texas A&M University, College Station, TX, 77843, USA
| | - Sneha Nadella
- Department of Biology, Texas A&M University, College Station, TX, 77843, USA
| | - Tucker Gillespie
- Department of Biology, Texas A&M University, College Station, TX, 77843, USA
| | - Christian Trevino
- Department of Biology, Texas A&M University, College Station, TX, 77843, USA
| | - Andrew Buxton
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, 77843, USA
| | - Anna L Pritchard
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, 77843, USA
| | | | - Dylan A McCreedy
- Department of Biology, Texas A&M University, College Station, TX, 77843, USA
- Texas A&M Institute for Neuroscience, Texas A&M University, College Station, TX, 77843, USA
- Department of Biomedical Engineering, Texas A&M University, College Station, TX, 77843, USA
| | - Jennifer N Dulin
- Department of Biology, Texas A&M University, College Station, TX, 77843, USA.
- Texas A&M Institute for Neuroscience, Texas A&M University, College Station, TX, 77843, USA.
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3
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Li JH, Wei TT, Guo L, Cao JH, Feng YK, Guo SN, Liu GH, Ding Y, Chai YR. Curcumin protects thymus against D-galactose-induced senescence in mice. NAUNYN-SCHMIEDEBERG'S ARCHIVES OF PHARMACOLOGY 2021; 394:411-420. [PMID: 32686020 DOI: 10.1007/s00210-020-01945-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2020] [Accepted: 07/08/2020] [Indexed: 12/11/2022]
Abstract
Senescence-related decline of thymus affects immune function in the elderly population and contributes to the prevalence of many relevant diseases like cancer, autoimmune diseases, and other chronic diseases. In this study, we investigated the therapeutic effects of curcumin, an agent that could counter aging, and explored its optimal intake and the alteration of autoimmune regulator (Aire) after curcumin treatment in the D-galactose (D-gal)-induced accelerated aging mice. ICR mice were intraperitoneally injected with D-gal for 8 weeks to establish the accelerated aging model and given curcumin with 50, 100, and 200 mg/kg body weight per day by gavage, respectively, for 6 weeks. It indicated that the D-gal-treated mice developed structural changes in the thymi compared with the control group without D-gal and curcumin treatment. As the supplements of curcumin, it resulted in a restoration of the normal thymic anatomy with an increase of proliferating cells and a reduction of apoptotic cells in the thymi of the D-gal-induced aging model mice. Curcumin administration could also expand the expression level of Aire from mRNA level and protein level. The current study demonstrated that curcumin could ameliorate senescence-related thymus involution via upregulating Aire expression, suggesting that curcumin can rejuvenate senescence-associated alterations of thymus induced by D-gal accumulation.
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Affiliation(s)
- Jie-Han Li
- Department of Histology and Embryology, School of Basic Medical Sciences, Zhengzhou University, No. 100 Ke Xue Road, Zhengzhou, 450001, Henan, China
| | - Ting-Ting Wei
- Department of Histology and Embryology, School of Basic Medical Sciences, Zhengzhou University, No. 100 Ke Xue Road, Zhengzhou, 450001, Henan, China
| | - Li Guo
- Department of Histology and Embryology, School of Basic Medical Sciences, Zhengzhou University, No. 100 Ke Xue Road, Zhengzhou, 450001, Henan, China
| | - Jia-Hui Cao
- Department of Histology and Embryology, School of Basic Medical Sciences, Zhengzhou University, No. 100 Ke Xue Road, Zhengzhou, 450001, Henan, China
| | - Yuan-Kang Feng
- Department of Histology and Embryology, School of Basic Medical Sciences, Zhengzhou University, No. 100 Ke Xue Road, Zhengzhou, 450001, Henan, China
| | - Shu-Ning Guo
- Department of Histology and Embryology, School of Basic Medical Sciences, Zhengzhou University, No. 100 Ke Xue Road, Zhengzhou, 450001, Henan, China
| | - Guo-Hong Liu
- Department of Histology and Embryology, School of Basic Medical Sciences, Zhengzhou University, No. 100 Ke Xue Road, Zhengzhou, 450001, Henan, China
| | - Yi Ding
- Department of Histology and Embryology, School of Basic Medical Sciences, Zhengzhou University, No. 100 Ke Xue Road, Zhengzhou, 450001, Henan, China
| | - Yu-Rong Chai
- Department of Histology and Embryology, School of Basic Medical Sciences, Zhengzhou University, No. 100 Ke Xue Road, Zhengzhou, 450001, Henan, China.
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4
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FoxJ1 regulates spinal cord development and is required for the maintenance of spinal cord stem cell potential. Exp Cell Res 2018; 368:84-100. [DOI: 10.1016/j.yexcr.2018.04.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 04/15/2018] [Indexed: 12/17/2022]
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Lai HC, Seal RP, Johnson JE. Making sense out of spinal cord somatosensory development. Development 2017; 143:3434-3448. [PMID: 27702783 DOI: 10.1242/dev.139592] [Citation(s) in RCA: 121] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The spinal cord integrates and relays somatosensory input, leading to complex motor responses. Research over the past couple of decades has identified transcription factor networks that function during development to define and instruct the generation of diverse neuronal populations within the spinal cord. A number of studies have now started to connect these developmentally defined populations with their roles in somatosensory circuits. Here, we review our current understanding of how neuronal diversity in the dorsal spinal cord is generated and we discuss the logic underlying how these neurons form the basis of somatosensory circuits.
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Affiliation(s)
- Helen C Lai
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Rebecca P Seal
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15260, USA
| | - Jane E Johnson
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
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6
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Kabayiza KU, Masgutova G, Harris A, Rucchin V, Jacob B, Clotman F. The Onecut Transcription Factors Regulate Differentiation and Distribution of Dorsal Interneurons during Spinal Cord Development. Front Mol Neurosci 2017; 10:157. [PMID: 28603487 PMCID: PMC5445119 DOI: 10.3389/fnmol.2017.00157] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 05/08/2017] [Indexed: 01/09/2023] Open
Abstract
During embryonic development, the dorsal spinal cord generates numerous interneuron populations eventually involved in motor circuits or in sensory networks that integrate and transmit sensory inputs from the periphery. The molecular mechanisms that regulate the specification of these multiple dorsal neuronal populations have been extensively characterized. In contrast, the factors that contribute to their diversification into smaller specialized subsets and those that control the specific distribution of each population in the developing spinal cord remain unknown. Here, we demonstrate that the Onecut transcription factors, namely Hepatocyte Nuclear Factor-6 (HNF-6) (or OC-1), OC-2 and OC-3, regulate the diversification and the distribution of spinal dorsal interneuron (dINs). Onecut proteins are dynamically and differentially distributed in spinal dINs during differentiation and migration. Analyzes of mutant embryos devoid of Onecut factors in the developing spinal cord evidenced a requirement in Onecut proteins for proper production of a specific subset of dI5 interneurons. In addition, the distribution of dI3, dI5 and dI6 interneuron populations was altered. Hence, Onecut transcription factors control genetic programs that contribute to the regulation of spinal dIN diversification and distribution during embryonic development.
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Affiliation(s)
- Karolina U Kabayiza
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural DifferentiationBrussels, Belgium.,Biology Department, School of Science, College of Science and Technology, University of RwandaButare, Rwanda
| | - Gauhar Masgutova
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural DifferentiationBrussels, Belgium
| | - Audrey Harris
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural DifferentiationBrussels, Belgium
| | - Vincent Rucchin
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural DifferentiationBrussels, Belgium
| | - Benvenuto Jacob
- Université catholique de Louvain, Institute of Neuroscience, System and Cognition DivisionBrussels, Belgium
| | - Frédéric Clotman
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural DifferentiationBrussels, Belgium
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7
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Kanduc D, Shoenfeld Y. From HBV to HPV: Designing vaccines for extensive and intensive vaccination campaigns worldwide. Autoimmun Rev 2016; 15:1054-1061. [DOI: 10.1016/j.autrev.2016.07.030] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2016] [Accepted: 07/12/2016] [Indexed: 12/12/2022]
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8
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Zannino DA, Sagerström CG. An emerging role for prdm family genes in dorsoventral patterning of the vertebrate nervous system. Neural Dev 2015; 10:24. [PMID: 26499851 PMCID: PMC4620005 DOI: 10.1186/s13064-015-0052-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Accepted: 10/13/2015] [Indexed: 12/13/2022] Open
Abstract
The embryonic vertebrate neural tube is divided along its dorsoventral (DV) axis into eleven molecularly discrete progenitor domains. Each of these domains gives rise to distinct neuronal cell types; the ventral-most six domains contribute to motor circuits, while the five dorsal domains contribute to sensory circuits. Following the initial neurogenesis step, these domains also generate glial cell types—either astrocytes or oligodendrocytes. This DV pattern is initiated by two morphogens—Sonic Hedgehog released from notochord and floor plate and Bone Morphogenetic Protein produced in the roof plate—that act in concentration gradients to induce expression of genes along the DV axis. Subsequently, these DV-restricted genes cooperate to define progenitor domains and to control neuronal cell fate specification and differentiation in each domain. Many genes involved in this process have been identified, but significant gaps remain in our understanding of the underlying genetic program. Here we review recent work identifying members of the Prdm gene family as novel regulators of DV patterning in the neural tube. Many Prdm proteins regulate transcription by controlling histone modifications (either via intrinsic histone methyltransferase activity, or by recruiting histone modifying enzymes). Prdm genes are expressed in spatially restricted domains along the DV axis of the neural tube and play important roles in the specification of progenitor domains, as well as in the subsequent differentiation of motor neurons and various types of interneurons. Strikingly, Prdm proteins appear to function by binding to, and modulating the activity of, other transcription factors (particularly bHLH proteins). The identity of key transcription factors in DV patterning of the neural tube has been elucidated previously (e.g. the nkx, bHLH and pax families), but it now appears that an additional family is also required and that it acts in a potentially novel manner.
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Affiliation(s)
- Denise A Zannino
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 364 Plantation St./LRB815, Worcester, MA, 01605-2324, USA.
| | - Charles G Sagerström
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 364 Plantation St./LRB815, Worcester, MA, 01605-2324, USA.
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9
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Huang L, Hu F, Feng L, Luo XJ, Liang G, Zeng XY, Yi JL, Gan L. Bhlhb5 is required for the subtype development of retinal amacrine and bipolar cells in mice. Dev Dyn 2013; 243:279-89. [PMID: 24123365 DOI: 10.1002/dvdy.24067] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Revised: 09/19/2013] [Accepted: 09/20/2013] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND BHLHB5, an OLIG-related basic helix-loop-helix transcription factor, is required for the development of a subset of gamma-amino butyric acid-releasing (GABAergic) amacrine cells and OFF-cone bipolar (CB) cells in mouse retinas. In order to determine BHLHB5's functional mechanism in retinogenesis, we used the Cre-loxP recombination system to genetically trace the lineage of BHLHB5+ cells in normal and Bhlhb5-null retinas. The Bhlhb5-Cre knock-in allele was used to activate the constitutive expression of a GFP reporter in the Bhlhb5-expressing cells, and the cell fates of Bhlhb5-lineage cells were identified by using specific cell markers and were compared between normal and Bhlhb5-null retinas. RESULTS In addition to GABAergic amacrine and OFF-CB cells, Bhlhb5 lineage cells give rise to ganglion, glycinergic amacrine, rod bipolar, ON-bipolar, and rod photoreceptor cells during normal retinal development. Targeted deletion of Bhlhb5 resulted in the loss of GABAergic amacrine, glycinergic amacrine, dopaminergic amacrine, and Type 2 OFF-CB cells. Furthermore, in the absence of BHLHB5, a portion of Bhlhb5 lineage cells switch their fate and differentiate into cholinergic amacrine cells. CONCLUSIONS Our data reveal a broad expression pattern of Bhlhb5 throughout retinogenesis and demonstrate the cell-autonomous as well as non-cell-autonomous role of Bhlhb5 in the specification of amacrine and bipolar subtypes.
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Affiliation(s)
- Liang Huang
- Medical College of Nanchang University, Nanchang, Jiangxi, China; Jiangxi Provincial People's Hospital, Nanchang, Jiangxi, China; First Affiliated Hospital, Gannan Medical University, Ganzhou, Jiangxi, China; Flaum Eye Institute and Department of Ophthalmology, University of Rochester, Rochester, New York
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10
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Francius C, Harris A, Rucchin V, Hendricks TJ, Stam FJ, Barber M, Kurek D, Grosveld FG, Pierani A, Goulding M, Clotman F. Identification of multiple subsets of ventral interneurons and differential distribution along the rostrocaudal axis of the developing spinal cord. PLoS One 2013; 8:e70325. [PMID: 23967072 PMCID: PMC3744532 DOI: 10.1371/journal.pone.0070325] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Accepted: 06/17/2013] [Indexed: 01/06/2023] Open
Abstract
The spinal cord contains neuronal circuits termed Central Pattern Generators (CPGs) that coordinate rhythmic motor activities. CPG circuits consist of motor neurons and multiple interneuron cell types, many of which are derived from four distinct cardinal classes of ventral interneurons, called V0, V1, V2 and V3. While significant progress has been made on elucidating the molecular and genetic mechanisms that control ventral interneuron differentiation, little is known about their distribution along the antero-posterior axis of the spinal cord and their diversification. Here, we report that V0, V1 and V2 interneurons exhibit distinct organizational patterns at brachial, thoracic and lumbar levels of the developing spinal cord. In addition, we demonstrate that each cardinal class of ventral interneurons can be subdivided into several subsets according to the combinatorial expression of different sets of transcription factors, and that these subsets are differentially distributed along the rostrocaudal axis of the spinal cord. This comprehensive molecular profiling of ventral interneurons provides an important resource for investigating neuronal diversification in the developing spinal cord and for understanding the contribution of specific interneuron subsets on CPG circuits and motor control.
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Affiliation(s)
- Cédric Francius
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural Differentiation, Brussels, Belgium
| | - Audrey Harris
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural Differentiation, Brussels, Belgium
| | - Vincent Rucchin
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural Differentiation, Brussels, Belgium
| | - Timothy J. Hendricks
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, California, United States of America
| | - Floor J. Stam
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, California, United States of America
| | - Melissa Barber
- CNRS UMR 7592, Institut Jacques Monod, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Dorota Kurek
- Erasmus MC Stem Cell Institute, Department of Cell Biology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Frank G. Grosveld
- Erasmus MC Stem Cell Institute, Department of Cell Biology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Alessandra Pierani
- CNRS UMR 7592, Institut Jacques Monod, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Martyn Goulding
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, California, United States of America
| | - Frédéric Clotman
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural Differentiation, Brussels, Belgium
- * E-mail:
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11
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Dual-mode operation of neuronal networks involved in left–right alternation. Nature 2013; 500:85-8. [DOI: 10.1038/nature12286] [Citation(s) in RCA: 238] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Accepted: 05/13/2013] [Indexed: 01/04/2023]
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12
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Oyallon J, Apitz H, Miguel-Aliaga I, Timofeev K, Ferreira L, Salecker I. Regulation of locomotion and motoneuron trajectory selection and targeting by the Drosophila homolog of Olig family transcription factors. Dev Biol 2012; 369:261-76. [PMID: 22796650 PMCID: PMC3464432 DOI: 10.1016/j.ydbio.2012.06.027] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2012] [Revised: 06/28/2012] [Accepted: 06/29/2012] [Indexed: 01/12/2023]
Abstract
During the development of locomotion circuits it is essential that motoneurons with distinct subtype identities select the correct trajectories and target muscles. In vertebrates, the generation of motoneurons and myelinating glia depends on Olig2, one of the five Olig family bHLH transcription factors. We investigated the so far unknown function of the single Drosophila homolog Oli. Combining behavioral and genetic approaches, we demonstrate that oli is not required for gliogenesis, but plays pivotal roles in regulating larval and adult locomotion, and axon pathfinding and targeting of embryonic motoneurons. In the embryonic nervous system, Oli is primarily expressed in postmitotic progeny, and in particular, in distinct ventral motoneuron subtypes. oli mediates axonal trajectory selection of these motoneurons within the ventral nerve cord and targeting to specific muscles. Genetic interaction assays suggest that oli acts as part of a conserved transcription factor ensemble including Lim3, Islet and Hb9. Moreover, oli is expressed in postembryonic leg-innervating motoneuron lineages and required in glutamatergic neurons for walking. Finally, over-expression of vertebrate Olig2 partially rescues the walking defects of oli-deficient flies. Thus, our findings reveal a remarkably conserved role of Drosophila Oli and vertebrate family members in regulating motoneuron development, while the steps that require their function differ in detail.
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Affiliation(s)
- Justine Oyallon
- Division of Molecular Neurobiology, MRC National Institute for Medical Research, London, UK
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13
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Zeilhofer HU, Wildner H, Yévenes GE. Fast synaptic inhibition in spinal sensory processing and pain control. Physiol Rev 2012; 92:193-235. [PMID: 22298656 DOI: 10.1152/physrev.00043.2010] [Citation(s) in RCA: 262] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The two amino acids GABA and glycine mediate fast inhibitory neurotransmission in different CNS areas and serve pivotal roles in the spinal sensory processing. Under healthy conditions, they limit the excitability of spinal terminals of primary sensory nerve fibers and of intrinsic dorsal horn neurons through pre- and postsynaptic mechanisms, and thereby facilitate the spatial and temporal discrimination of sensory stimuli. Removal of fast inhibition not only reduces the fidelity of normal sensory processing but also provokes symptoms very much reminiscent of pathological and chronic pain syndromes. This review summarizes our knowledge of the molecular bases of spinal inhibitory neurotransmission and its organization in dorsal horn sensory circuits. Particular emphasis is placed on the role and mechanisms of spinal inhibitory malfunction in inflammatory and neuropathic chronic pain syndromes.
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14
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Waite MR, Skaggs K, Kaviany P, Skidmore JM, Causeret F, Martin JF, Martin DM. Distinct populations of GABAergic neurons in mouse rhombomere 1 express but do not require the homeodomain transcription factor PITX2. Mol Cell Neurosci 2012; 49:32-43. [PMID: 21925604 PMCID: PMC3244529 DOI: 10.1016/j.mcn.2011.08.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2011] [Revised: 08/04/2011] [Accepted: 08/30/2011] [Indexed: 11/20/2022] Open
Abstract
Hindbrain rhombomere 1 (r1) is located caudal to the isthmus, a critical organizer region, and rostral to rhombomere 2 in the developing mouse brain. Dorsal r1 gives rise to the cerebellum, locus coeruleus, and several brainstem nuclei, whereas cells from ventral r1 contribute to the trochlear and trigeminal nuclei as well as serotonergic and GABAergic neurons of the dorsal raphe. Recent studies have identified several molecular events controlling dorsal r1 development. In contrast, very little is known about ventral r1 gene expression and the genetic mechanisms regulating its formation. Neurons with distinct neurotransmitter phenotypes have been identified in ventral r1 including GABAergic, serotonergic, and cholinergic neurons. Here we show that PITX2 marks a distinct population of GABAergic neurons in mouse embryonic ventral r1. This population appears to retain its GABAergic identity even in the absence of PITX2. We provide a comprehensive map of markers that places these PITX2-positive GABAergic neurons in a region of r1 that intersects and is potentially in communication with the dorsal raphe.
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Affiliation(s)
- Mindy R Waite
- Program in Cell and Molecular Biology, 2966 Taubman Medical Library, University of Michigan, Ann Arbor, MI 48109-0619, USA.
| | - Kaia Skaggs
- Department of Neurology, 3520A MSRB I, University of Michigan, Ann Arbor, MI, 48019-5652, USA.
| | - Parisa Kaviany
- Department of Pediatrics, 3520A MSRB I, University of Michigan, Ann Arbor, MI, 48019-5652, USA.
| | - Jennifer M Skidmore
- Department of Pediatrics, 3520A MSRB I, University of Michigan, Ann Arbor, MI, 48019-5652, USA.
| | - Frédéric Causeret
- Institut Jacques Monod, Université Paris Diderot, CNRS UMR 7592, Sorbonne Paris Cité, Paris, France.
| | - James F Martin
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Cardiomyocyte Renewal Lab Texas Heart Institute, Houston Texas, 77030, USA.
| | - Donna M Martin
- Program in Cell and Molecular Biology, 2966 Taubman Medical Library, University of Michigan, Ann Arbor, MI 48109-0619, USA; Department of Pediatrics, 3520A MSRB I, University of Michigan, Ann Arbor, MI, 48019-5652, USA; Department of Human Genetics, 3520A MSRB I, University of Michigan, Ann Arbor, MI, 48019-5652, USA.
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15
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Skaggs K, Martin DM, Novitch BG. Regulation of spinal interneuron development by the Olig-related protein Bhlhb5 and Notch signaling. Development 2011; 138:3199-211. [PMID: 21750031 DOI: 10.1242/dev.057281] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The neural circuits that control motor activities depend on the spatially and temporally ordered generation of distinct classes of spinal interneurons. Despite the importance of these interneurons, the mechanisms underlying their genesis are poorly understood. Here, we demonstrate that the Olig-related transcription factor Bhlhb5 (recently renamed Bhlhe22) plays two central roles in this process. Our findings suggest that Bhlhb5 repressor activity acts downstream of retinoid signaling and homeodomain proteins to promote the formation of dI6, V1 and V2 interneuron progenitors and their differentiated progeny. In addition, Bhlhb5 is required to organize the spatially restricted expression of the Notch ligands and Fringe proteins that both elicit the formation of the interneuron populations that arise adjacent to Bhlhb5(+) cells and influence the global pattern of neuronal differentiation. Through these actions, Bhlhb5 helps transform the spatial information established by morphogen signaling into local cell-cell interactions associated with Notch signaling that control the progression of neurogenesis and extend neuronal diversity within the developing spinal cord.
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Affiliation(s)
- Kaia Skaggs
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
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Harrison MRM, Georgiou AS, Spaink HP, Cunliffe VT. The epigenetic regulator Histone Deacetylase 1 promotes transcription of a core neurogenic programme in zebrafish embryos. BMC Genomics 2011; 12:24. [PMID: 21226904 PMCID: PMC3032698 DOI: 10.1186/1471-2164-12-24] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2010] [Accepted: 01/12/2011] [Indexed: 12/29/2022] Open
Abstract
Background The epigenetic regulator Histone Deacetylase 1 (Hdac1) is required for specification and patterning of neurones and myelinating glia during development of the vertebrate central nervous system (CNS). This co-ordinating function for Hdac1 is evolutionarily conserved in zebrafish and mouse, but the mechanism of action of Hdac1 in the developing CNS is not well-understood. Results A genome-wide comparative analysis of the transcriptomes of Hdac1-deficient and wild-type zebrafish embryos was performed, which identified an extensive programme of gene expression that is regulated by Hdac1 in the developing embryo. Using time-resolved expression profiling of embryos, we then identified a small subset of 54 genes within the Hdac1-regulated transcriptome that specifically exhibit robust and sustained Hdac1-dependent expression from early neurogenesis onwards. 18 of these 54 stringently Hdac1-regulated genes encode DNA-binding transcription factors that are implicated in promoting neuronal specification and CNS patterning, including the proneural bHLH proteins Ascl1a and Ascl1b, as well as Neurod4 and Neurod. Relatively few genes are strongly repressed by Hdac1 but expression of the Notch target gene her6 is attenuated by Hdac1 in specific sub-regions of the developing CNS, from early stages of neurogenesis onwards. Selected members of the stringently Hdac1-regulated group of genes were tested for Hdac1 binding to their promoter-proximal cis-regulatory elements. Surprisingly, we found that Hdac1 is specifically and stably associated with DNA sequences within the promoter region of ascl1b during neurogenesis, and that this Hdac1-ascl1b interaction is abolished in hdac1 mutant embryos. Conclusions We conclude that Hdac1 regulates histone acetylation and methylation in the developing zebrafish embryo and promotes the sustained, co-ordinate transcription of a small set of transcription factor genes that control expansion and diversification of cell fates within the developing CNS. Our in vivo chromatin immunoprecipitation results also suggest a specific function for Hdac1 in directly regulating transcription of a key member of this group of genes, ascl1b, from the beginning of neurogenesis onwards. Taken together, our observations indicate a novel role for Hdac1 as a positive regulator of gene transcription during development of the vertebrate CNS, in addition to its more well-established function in transcriptional repression.
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Affiliation(s)
- Michael R M Harrison
- MRC Centre for Developmental and Biomedical Genetics, Department of Biomedical Science, University of Sheffield, Western Bank, Sheffield S10 2TN, United Kingdom
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Abstract
A subset of preBötzinger Complex (preBötC) neurokinin 1 receptor (NK1R) and somatostatin peptide (SST)-expressing neurons are necessary for breathing in adult rats, in vivo. Their developmental origins and relationship to other preBötC glutamatergic neurons are unknown. Here we show, in mice, that the "core" of preBötC SST(+)/NK1R(+)/SST 2a receptor(+) (SST2aR) neurons, are derived from Dbx1-expressing progenitors. We also show that Dbx1-derived neurons heterogeneously coexpress NK1R and SST2aR within and beyond the borders of preBötC. More striking, we find that nearly all non-catecholaminergic glutamatergic neurons of the ventrolateral medulla (VLM) are also Dbx1 derived. PreBötC SST(+) neurons are born between E9.5 and E11.5 in the same proportion as non-SST-expressing neurons. Additionally, preBötC Dbx1 neurons are respiratory modulated and show an early inspiratory phase of firing in rhythmically active slice preparations. Loss of Dbx1 eliminates all glutamatergic neurons from the respiratory VLM including preBötC NK1R(+)/SST(+) neurons. Dbx1 mutant mice do not express any spontaneous respiratory behaviors in vivo. Moreover, they do not generate rhythmic inspiratory activity in isolated en bloc preparations even after acidic or serotonergic stimulation. These data indicate that preBötC core neurons represent a subset of a larger, more heterogeneous population of VLM Dbx1-derived neurons. These data indicate that Dbx1-derived neurons are essential for the expression and, we hypothesize, are responsible for the generation of respiratory behavior both in vitro and in vivo.
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Ramos C, Rocha S, Gaspar C, Henrique D. Two Notch ligands, Dll1 and Jag1, are differently restricted in their range of action to control neurogenesis in the mammalian spinal cord. PLoS One 2010; 5:e15515. [PMID: 21124801 PMCID: PMC2991363 DOI: 10.1371/journal.pone.0015515] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2010] [Accepted: 10/10/2010] [Indexed: 02/07/2023] Open
Abstract
Background Notch signalling regulates neuronal differentiation in the vertebrate nervous system. In addition to a widespread function in maintaining neural progenitors, Notch signalling has also been involved in specific neuronal fate decisions. These functions are likely mediated by distinct Notch ligands, which show restricted expression patterns in the developing nervous system. Two ligands, in particular, are expressed in non-overlapping complementary domains of the embryonic spinal cord, with Jag1 being restricted to the V1 and dI6 progenitor domains, while Dll1 is expressed in the remaining domains. However, the specific contribution of different ligands to regulate neurogenesis in vertebrate embryos is still poorly understood. Methodology/Principal Findings In this work, we investigated the role of Jag1 and Dll1 during spinal cord neurogenesis, using conditional knockout mice where the two genes are deleted in the neuroepithelium, singly or in combination. Our analysis showed that Jag1 deletion leads to a modest increase in V1 interneurons, while dI6 neurogenesis was unaltered. This mild Jag1 phenotype contrasts with the strong neurogenic phenotype detected in Dll1 mutants and led us to hypothesize that neighbouring Dll1-expressing cells signal to V1 and dI6 progenitors and restore neurogenesis in the absence of Jag1. Analysis of double Dll1;Jag1 mutant embryos revealed a stronger increase in V1-derived interneurons and overproduction of dI6 interneurons. In the presence of a functional Dll1 allele, V1 neurogenesis is restored to the levels detected in single Jag1 mutants, while dI6 neurogenesis returns to normal, thereby confirming that Dll1-mediated signalling compensates for Jag1 deletion in V1 and dI6 domains. Conclusions/Significance Our results reveal that Dll1 and Jag1 are functionally equivalent in controlling the rate of neurogenesis within their expression domains. However, Jag1 can only activate Notch signalling within the V1 and dI6 domains, whereas Dll1 can signal to neural progenitors both inside and outside its domains of expression.
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Affiliation(s)
- Catarina Ramos
- Faculdade de Medicina de Lisboa, Instituto de Medicina Molecular, Lisboa, Portugal
| | - Susana Rocha
- Faculdade de Medicina de Lisboa, Instituto de Medicina Molecular, Lisboa, Portugal
| | - Claudia Gaspar
- Faculdade de Medicina de Lisboa, Instituto de Medicina Molecular, Lisboa, Portugal
| | - Domingos Henrique
- Faculdade de Medicina de Lisboa, Instituto de Medicina Molecular, Lisboa, Portugal
- * E-mail:
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Ross SE, Mardinly AR, McCord AE, Zurawski J, Cohen S, Jung C, Hu L, Mok SI, Shah A, Savner E, Tolias C, Corfas R, Chen S, Inquimbert P, Xu Y, McInnes RR, Rice FL, Corfas G, Ma Q, Woolf CJ, Greenberg ME. Loss of inhibitory interneurons in the dorsal spinal cord and elevated itch in Bhlhb5 mutant mice. Neuron 2010; 65:886-98. [PMID: 20346763 PMCID: PMC2856621 DOI: 10.1016/j.neuron.2010.02.025] [Citation(s) in RCA: 322] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/19/2010] [Indexed: 12/21/2022]
Abstract
Itch is the least well understood of all the somatic senses, and the neural circuits that underlie this sensation are poorly defined. Here we show that the atonal-related transcription factor Bhlhb5 is transiently expressed in the dorsal horn of the developing spinal cord and appears to play a role in the formation and regulation of pruritic (itch) circuits. Mice lacking Bhlhb5 develop self-inflicted skin lesions and show significantly enhanced scratching responses to pruritic agents. Through genetic fate-mapping and conditional ablation, we provide evidence that the pruritic phenotype in Bhlhb5 mutants is due to selective loss of a subset of inhibitory interneurons in the dorsal horn. Our findings suggest that Bhlhb5 is required for the survival of a specific population of inhibitory interneurons that regulate pruritus, and provide evidence that the loss of inhibitory synaptic input results in abnormal itch.
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Affiliation(s)
- Sarah E. Ross
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, Massachusetts 02115, USA
| | - Alan R. Mardinly
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, Massachusetts 02115, USA
| | - Alejandra E. McCord
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, Massachusetts 02115, USA
| | - Jonathan Zurawski
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, Massachusetts 02115, USA
| | - Sonia Cohen
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, Massachusetts 02115, USA
| | - Cynthia Jung
- Programs in Developmental Biology, and Genetics and the Department of Molecular Genetics, The Research Institute, Hospital for Sick Children, 555 University Ave., Toronto, Ontario, M5G 1X8, Canada
| | - Linda Hu
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, Massachusetts 02115, USA
| | - Stephanie I. Mok
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, Massachusetts 02115, USA
| | - Anar Shah
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, Massachusetts 02115, USA
| | - Erin Savner
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, Massachusetts 02115, USA
| | - Christos Tolias
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, Massachusetts 02115, USA
| | - Roman Corfas
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, Massachusetts 02115, USA
| | - Suzhen Chen
- F. M. Kirby Neurobiology Center, Children's Hospital, and Departments of Neurology and Neurobiology, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Perrine Inquimbert
- F. M. Kirby Neurobiology Center, Children's Hospital, and Departments of Neurology and Neurobiology, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Yi Xu
- Dana-Farber Cancer Institute and Department of Neurobiology, Harvard Medical School, 1 Jimmy Fund Way, Boston, MA 02115, USA
| | - Roderick R. McInnes
- Programs in Developmental Biology, and Genetics and the Department of Molecular Genetics, The Research Institute, Hospital for Sick Children, 555 University Ave., Toronto, Ontario, M5G 1X8, Canada
- Department of Pediatrics and the Institute of Medical Science, University of Toronto, Toronto, Ontario, Canada
| | - Frank L. Rice
- Center for Neuropharmacology and Neuroscience, Albany Medical College, Albany, NY, 12208 and Integrated Tissue Dynamics LL, Renssalaer, NY 12144, USA
| | - Gabriel Corfas
- F. M. Kirby Neurobiology Center, Children's Hospital, and Departments of Neurology and Neurobiology, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Qiufu Ma
- Dana-Farber Cancer Institute and Department of Neurobiology, Harvard Medical School, 1 Jimmy Fund Way, Boston, MA 02115, USA
| | - Clifford J. Woolf
- F. M. Kirby Neurobiology Center, Children's Hospital, and Departments of Neurology and Neurobiology, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA
| | - Michael E. Greenberg
- Department of Neurobiology, Harvard Medical School, 220 Longwood Avenue, Boston, Massachusetts 02115, USA
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Bröhl D, Strehle M, Wende H, Hori K, Bormuth I, Nave KA, Müller T, Birchmeier C. A transcriptional network coordinately determines transmitter and peptidergic fate in the dorsal spinal cord. Dev Biol 2008; 322:381-93. [PMID: 18721803 DOI: 10.1016/j.ydbio.2008.08.002] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2008] [Revised: 06/21/2008] [Accepted: 08/01/2008] [Indexed: 01/19/2023]
Abstract
Dorsal horn neurons express many different neuropeptides that modulate sensory perception like the sensation of pain. Inhibitory neurons of the dorsal horn derive from postmitotic neurons that express Pax2, Lbx1 and Lhx1/5, and diversify during maturation. In particular, fractions of maturing inhibitory neurons express various neuropeptides. We demonstrate here that a coordinate molecular mechanism determines inhibitory and peptidergic fate in the developing dorsal horn. A bHLH factor complex that contains Ptf1a acts as upstream regulator and initiates the expression of several downstream transcription factors in the future inhibitory neurons, of which Pax2 is known to determine the neurotransmitter phenotype. We demonstrate here that dynorphin, galanin, NPY, nociceptin and enkephalin expression depends on Ptf1a, indicating that these neuropeptides are expressed in inhibitory neurons. Furthermore, we show that Neurod1/2/6 and Lhx1/5, which act downstream of Ptf1a, control distinct aspects of peptidergic differentiation. In particular, the Neurod1/2/6 factors are essential for dynorphin and galanin expression, whereas the Lhx1/5 factors are essential for NPY expression. We conclude that a transcriptional network operates in maturing dorsal horn neurons that coordinately determines transmitter and peptidergic fate.
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Affiliation(s)
- Dominique Bröhl
- Department of Neuroscience, Max-Delbrück-Centrum for Molecular Medicine, Berlin, Germany
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