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Hao S, Zhu X, Huang Z, Yang Q, Liu H, Wu Y, Zhan Y, Dong Y, Li C, Wang H, Haasdijk E, Wu Z, Li S, Yan H, Zhu L, Guo S, Wang Z, Ye A, Lin Y, Cui L, Tan X, Liu H, Wang M, Chen J, Zhong Y, Du W, Wang G, Lai T, Cao M, Yang T, Xu Y, Li L, Yu Q, Zhuang Z, Xia Y, Lei Y, An Y, Cheng M, Zhao Y, Han L, Yuan Y, Song X, Song Y, Gu L, Liu C, Lin X, Wang R, Wang Z, Wang Y, Li S, Li H, Song J, Chen M, Zhou W, Yuan N, Sun S, Wang S, Chen Y, Zheng M, Fang J, Zhang R, Zhang S, Chai Q, Liu J, Wei W, He J, Zhou H, Sun Y, Liu Z, Liu C, Yao J, Liang Z, Xu X, Poo M, Li C, De Zeeuw CI, Shen Z, Liu Z, Liu L, Liu S, Sun Y, Liu C. Cross-species single-cell spatial transcriptomic atlases of the cerebellar cortex. Science 2024; 385:eado3927. [PMID: 39325889 DOI: 10.1126/science.ado3927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Accepted: 08/14/2024] [Indexed: 09/28/2024]
Abstract
The molecular and cellular organization of the primate cerebellum remains poorly characterized. We obtained single-cell spatial transcriptomic atlases of macaque, marmoset, and mouse cerebella and identified primate-specific cell subtypes, including Purkinje cells and molecular-layer interneurons, that show different expression of the glutamate ionotropic receptor Delta type subunit 2 (GRID2) gene. Distinct gene expression profiles were found in anterior, posterior, and vestibular regions in all species, whereas region-selective gene expression was predominantly observed in the granular layer of primates and in the Purkinje layer of mice. Gene expression gradients in the cerebellar cortex matched well with functional connectivity gradients revealed with awake functional magnetic resonance imaging, with more lobule-specific differences between primates and mice than between two primate species. These comprehensive atlases and comparative analyses provide the basis for understanding cerebellar evolution and function.
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Affiliation(s)
| | - Xiaojia Zhu
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Key Laboratory of Genetic Evolution & Animal Models, Chinese Academy of Sciences, Shanghai, 200031, China
- Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, 650201, China
| | - Zhi Huang
- BGI Research, Hangzhou 310030, China
- BGI Research, Shenzhen 518083, China
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, China
| | - Qianqian Yang
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Hean Liu
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Yan Wu
- BGI Research, Hangzhou 310030, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yafeng Zhan
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Yu Dong
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
- Lingang Laboratory, Shanghai 200031, China
| | - Chao Li
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
| | - He Wang
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Elize Haasdijk
- Department of Neuroscience, Erasmus MC, 3015 GE Rotterdam, Netherlands
- Netherlands Institute for Neuroscience, Royal Academy of Arts and Sciences, 1105 BA Amsterdam, Netherlands
| | - Zihan Wu
- Tencent AI Lab, Shenzhen 518057, China
| | - Shenglong Li
- BGI Research, Hangzhou 310030, China
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou 510006, China
| | - Haotian Yan
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Lijing Zhu
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
| | | | - Zefang Wang
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Aojun Ye
- University of Chinese Academy of Sciences, Beijing 100049, China
| | | | - Luman Cui
- BGI Research, Shenzhen 518083, China
| | - Xing Tan
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
| | | | - Mingli Wang
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
- Lingang Laboratory, Shanghai 200031, China
| | - Jing Chen
- China National GeneBank, BGI Research, Shenzhen 518120, China
| | - Yanqing Zhong
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Wensi Du
- China National GeneBank, BGI Research, Shenzhen 518120, China
| | - Guangling Wang
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Tingting Lai
- China National GeneBank, BGI Research, Shenzhen 518120, China
| | - Mengdi Cao
- Key Laboratory of Genetic Evolution & Animal Models, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Tao Yang
- China National GeneBank, BGI Research, Shenzhen 518120, China
| | - Yuanfang Xu
- Key Laboratory of Genetic Evolution & Animal Models, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Ling Li
- China National GeneBank, BGI Research, Shenzhen 518120, China
| | - Qian Yu
- Key Laboratory of Genetic Evolution & Animal Models, Chinese Academy of Sciences, Shanghai, 200031, China
| | | | - Ying Xia
- Key Laboratory of Genetic Evolution & Animal Models, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Ying Lei
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Yingjie An
- Key Laboratory of Genetic Evolution & Animal Models, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Mengnan Cheng
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Yun Zhao
- Key Laboratory of Genetic Evolution & Animal Models, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Lei Han
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Yue Yuan
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Xinxiang Song
- Key Laboratory of Genetic Evolution & Animal Models, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Yumo Song
- BGI Research, Shenzhen 518083, China
| | - Liqin Gu
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Chang Liu
- BGI Research, Shenzhen 518083, China
| | | | - Ruiqi Wang
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
| | | | - Yang Wang
- BGI Research, Shenzhen 518083, China
| | - Shenyu Li
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Huanhuan Li
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Jingjing Song
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Mengni Chen
- Key Laboratory of Genetic Evolution & Animal Models, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Wanqiu Zhou
- Key Laboratory of Genetic Evolution & Animal Models, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Nini Yuan
- Key Laboratory of Genetic Evolution & Animal Models, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Suhong Sun
- Key Laboratory of Genetic Evolution & Animal Models, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Shiwen Wang
- Key Laboratory of Genetic Evolution & Animal Models, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Yu Chen
- Key Laboratory of Genetic Evolution & Animal Models, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Mingyuan Zheng
- Key Laboratory of Genetic Evolution & Animal Models, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Jiao Fang
- Key Laboratory of Genetic Evolution & Animal Models, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Ruiyi Zhang
- Key Laboratory of Genetic Evolution & Animal Models, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Shuzhen Zhang
- Key Laboratory of Genetic Evolution & Animal Models, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Qinwen Chai
- Key Laboratory of Genetic Evolution & Animal Models, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Jiabing Liu
- Key Laboratory of Genetic Evolution & Animal Models, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Wu Wei
- Lingang Laboratory, Shanghai 200031, China
| | - Jie He
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Haibo Zhou
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yangang Sun
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhen Liu
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chuanyu Liu
- BGI Research, Hangzhou 310030, China
- BGI Research, Shenzhen 518083, China
- Shanxi Medical University-BGI Collaborative Center for Future Medicine, Shanxi Medical University, Taiyuan 030001, China
| | | | - Zhifeng Liang
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xun Xu
- BGI Research, Hangzhou 310030, China
- Shanxi Medical University-BGI Collaborative Center for Future Medicine, Shanxi Medical University, Taiyuan 030001, China
| | - Muming Poo
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Shanghai Center for Brain Science and Brain-Inspired Technology, Shanghai 201602, China
| | - Chengyu Li
- Lingang Laboratory, Shanghai 200031, China
| | - Chris I De Zeeuw
- Department of Neuroscience, Erasmus MC, 3015 GE Rotterdam, Netherlands
- Netherlands Institute for Neuroscience, Royal Academy of Arts and Sciences, 1105 BA Amsterdam, Netherlands
| | - Zhiming Shen
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Shanghai Center for Brain Science and Brain-Inspired Technology, Shanghai 201602, China
| | - Zhiyong Liu
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Longqi Liu
- BGI Research, Hangzhou 310030, China
- Shanxi Medical University-BGI Collaborative Center for Future Medicine, Shanxi Medical University, Taiyuan 030001, China
| | - Shiping Liu
- BGI Research, Hangzhou 310030, China
- BGI Research, Shenzhen 518083, China
| | - Yidi Sun
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Key Laboratory of Genetic Evolution & Animal Models, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Cirong Liu
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Key Laboratory of Genetic Evolution & Animal Models, Chinese Academy of Sciences, Shanghai, 200031, China
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2
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Ojiro R, Ozawa S, Zou X, Tang Q, Woo GH, Shibutani M. Similar toxicity potential of glyphosate and glyphosate-based herbicide on cerebellar development after maternal exposure in rats. ENVIRONMENTAL TOXICOLOGY 2024; 39:3040-3054. [PMID: 38314887 DOI: 10.1002/tox.24163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 11/10/2023] [Accepted: 01/18/2024] [Indexed: 02/07/2024]
Abstract
Studies on the effects of glyphosate (GlyP) and glyphosate-based herbicides (GBHs) on cerebellar development are extremely limited. This study examined the effects of maternal exposure to GlyP and GBH on rat cerebellar development in male offspring. From day 6 of gestation until day 21 postpartum at weaning, dams were given GlyP at 1.5% or 3.0% in diet or GBH at 1.0% in drinking water (corresponding to 0.36% GlyP). At weaning, GBH exposure was linked to increased numbers of DCX+ migrating granule cells in the cortex and TUNEL+ apoptotic cells in the internal granular layer (IGL), suggesting the disappearance of mismigrated granule cells via apoptosis. GBH also upregulated Nr4a3 and downregulated Cdk5 in the cerebellar vermis, suggesting a causal relation with the impaired granule cell development at this time. GlyP (3.0%) tended to increase in the number of DCX+ migrating granule cells in the IGL and upregulated Nr4a3 at weaning. Both compounds also upregulated genes related to granule cell migration (Astn1, Astn2, Nfia, and/or Nfix) at weaning and in adulthood, which might be an ameliorative response to delayed granule cell migration. Moreover, GBH induced Purkinje cell misalignment at weaning, which could be the result of delayed granule cell migration. In adulthood, GBH was associated with upregulation of the reelin signaling-related genes Reln, Dab1, and Efnb1, suggesting a compensatory response to Purkinje cell misalignment. GlyP induced the same gene expression changes. These results suggest that GBH reversibly disrupts cerebellar development, primarily by targeting granule cell migration and differentiation, whereas GlyP exhibited similar toxic potential as GBH.
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Affiliation(s)
- Ryota Ojiro
- Laboratory of Veterinary Pathology, Division of Animal Life Science, Institute of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan
- Cooperative Division of Veterinary Sciences, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Shunsuke Ozawa
- Laboratory of Veterinary Pathology, Division of Animal Life Science, Institute of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan
- Cooperative Division of Veterinary Sciences, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Xinyu Zou
- Laboratory of Veterinary Pathology, Division of Animal Life Science, Institute of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan
- Cooperative Division of Veterinary Sciences, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Qian Tang
- Laboratory of Veterinary Pathology, Division of Animal Life Science, Institute of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan
- Cooperative Division of Veterinary Sciences, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Gye-Hyeong Woo
- Laboratory of Histopathology, Department of Clinical Laboratory Science, Semyung University, Jecheon-si, Chungbuk, Korea
| | - Makoto Shibutani
- Laboratory of Veterinary Pathology, Division of Animal Life Science, Institute of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan
- Cooperative Division of Veterinary Sciences, Graduate School of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan
- Institute of Global Innovation Research, Tokyo University of Agriculture and Technology, Tokyo, Japan
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3
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Tejwani L, Ravindra NG, Lee C, Cheng Y, Nguyen B, Luttik K, Ni L, Zhang S, Morrison LM, Gionco J, Xiang Y, Yoon J, Ro H, Haidery F, Grijalva RM, Bae E, Kim K, Martuscello RT, Orr HT, Zoghbi HY, McLoughlin HS, Ranum LPW, Shakkottai VG, Faust PL, Wang S, van Dijk D, Lim J. Longitudinal single-cell transcriptional dynamics throughout neurodegeneration in SCA1. Neuron 2024; 112:362-383.e15. [PMID: 38016472 PMCID: PMC10922326 DOI: 10.1016/j.neuron.2023.10.039] [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: 12/15/2022] [Revised: 09/10/2023] [Accepted: 10/27/2023] [Indexed: 11/30/2023]
Abstract
Neurodegeneration is a protracted process involving progressive changes in myriad cell types that ultimately results in the death of vulnerable neuronal populations. To dissect how individual cell types within a heterogeneous tissue contribute to the pathogenesis and progression of a neurodegenerative disorder, we performed longitudinal single-nucleus RNA sequencing of mouse and human spinocerebellar ataxia type 1 (SCA1) cerebellar tissue, establishing continuous dynamic trajectories of each cell population. Importantly, we defined the precise transcriptional changes that precede loss of Purkinje cells and, for the first time, identified robust early transcriptional dysregulation in unipolar brush cells and oligodendroglia. Finally, we applied a deep learning method to predict disease state accurately and identified specific features that enable accurate distinction of wild-type and SCA1 cells. Together, this work reveals new roles for diverse cerebellar cell types in SCA1 and provides a generalizable analysis framework for studying neurodegeneration.
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Affiliation(s)
- Leon Tejwani
- Interdepartmental Neuroscience Program, Yale School of Medicine, New Haven, CT 06510, USA; Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA.
| | - Neal G Ravindra
- Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA; Department of Computer Science, Yale University, New Haven, CT 06510, USA
| | - Changwoo Lee
- Interdepartmental Neuroscience Program, Yale School of Medicine, New Haven, CT 06510, USA; Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Yubao Cheng
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA
| | - Billy Nguyen
- University of California, San Francisco School of Medicine, San Francisco, CA 94143, USA
| | - Kimberly Luttik
- Interdepartmental Neuroscience Program, Yale School of Medicine, New Haven, CT 06510, USA; Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | - Luhan Ni
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA
| | - Shupei Zhang
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA
| | - Logan M Morrison
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA; Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI 48109, USA
| | - John Gionco
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center and the New York Presbyterian Hospital, New York, NY 10032, USA
| | - Yangfei Xiang
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA; Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06510, USA
| | | | - Hannah Ro
- Yale College, New Haven, CT 06510, USA
| | | | - Rosalie M Grijalva
- Interdepartmental Neuroscience Program, Yale School of Medicine, New Haven, CT 06510, USA; Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA
| | | | - Kristen Kim
- Interdepartmental Neuroscience Program, Yale School of Medicine, New Haven, CT 06510, USA; Department of Psychiatry, Yale School of Medicine, New Haven, CT 06510, USA
| | - Regina T Martuscello
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center and the New York Presbyterian Hospital, New York, NY 10032, USA
| | - Harry T Orr
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN 55455, USA
| | - Huda Y Zoghbi
- Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX 77030, USA; Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA; Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030, USA
| | - Hayley S McLoughlin
- Department of Neurology, University of Michigan, Ann Arbor, MI 48109-2200, USA
| | - Laura P W Ranum
- Department of Molecular Genetics and Microbiology, Center for Neurogenetics, College of Medicine, Genetics Institute, McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA
| | - Vikram G Shakkottai
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Phyllis L Faust
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center and the New York Presbyterian Hospital, New York, NY 10032, USA
| | - Siyuan Wang
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA; Department of Cell Biology, Yale School of Medicine, New Haven, CT 06510, USA.
| | - David van Dijk
- Cardiovascular Research Center, Section of Cardiovascular Medicine, Department of Internal Medicine, Yale School of Medicine, New Haven, CT 06510, USA; Department of Computer Science, Yale University, New Haven, CT 06510, USA.
| | - Janghoo Lim
- Interdepartmental Neuroscience Program, Yale School of Medicine, New Haven, CT 06510, USA; Department of Neuroscience, Yale School of Medicine, New Haven, CT 06510, USA; Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA; Yale Stem Cell Center, Yale School of Medicine, New Haven, CT 06510, USA; Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale School of Medicine, New Haven, CT 06510, USA; Wu Tsai Institute, Yale School of Medicine, New Haven, CT 06510, USA.
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4
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Hariani HN, Algstam AB, Candler CT, Witteveen IF, Sidhu JK, Balmer TS. A system of feed-forward cerebellar circuits that extend and diversify sensory signaling. eLife 2024; 12:RP88321. [PMID: 38270517 PMCID: PMC10945699 DOI: 10.7554/elife.88321] [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] [Indexed: 01/26/2024] Open
Abstract
Sensory signals are processed by the cerebellum to coordinate movements. Numerous cerebellar functions are thought to require the maintenance of a sensory representation that extends beyond the input signal. Granule cells receive sensory input, but they do not prolong the signal and are thus unlikely to maintain a sensory representation for much longer than the inputs themselves. Unipolar brush cells (UBCs) are excitatory interneurons that project to granule cells and transform sensory input into prolonged increases or decreases in firing, depending on their ON or OFF UBC subtype. Further extension and diversification of the input signal could be produced by UBCs that project to one another, but whether this circuitry exists is unclear. Here we test whether UBCs innervate one another and explore how these small networks of UBCs could transform spiking patterns. We characterized two transgenic mouse lines electrophysiologically and immunohistochemically to confirm that they label ON and OFF UBC subtypes and crossed them together, revealing that ON and OFF UBCs innervate one another. A Brainbow reporter was used to label UBCs of the same ON or OFF subtype with different fluorescent proteins, which showed that UBCs innervate their own subtypes as well. Computational models predict that these feed-forward networks of UBCs extend the length of bursts or pauses and introduce delays-transformations that may be necessary for cerebellar functions from modulation of eye movements to adaptive learning across time scales.
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Affiliation(s)
- Harsh N Hariani
- Interdisciplinary Graduate Program in Neuroscience, Arizona State UniversityTempeUnited States
- School of Life Sciences, Arizona State UniversityTempeUnited States
| | - A Brynn Algstam
- School of Life Sciences, Arizona State UniversityTempeUnited States
- Barrett Honors College, Arizona State UniversityTempeUnited States
| | - Christian T Candler
- Interdisciplinary Graduate Program in Neuroscience, Arizona State UniversityTempeUnited States
- School of Life Sciences, Arizona State UniversityTempeUnited States
| | | | - Jasmeen K Sidhu
- School of Life Sciences, Arizona State UniversityTempeUnited States
| | - Timothy S Balmer
- School of Life Sciences, Arizona State UniversityTempeUnited States
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5
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Hariani HN, Algstam AB, Candler CT, Witteveen IF, Sidhu JK, Balmer TS. A system of feed-forward cerebellar circuits that extend and diversify sensory signaling. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.11.536335. [PMID: 37090638 PMCID: PMC10120650 DOI: 10.1101/2023.04.11.536335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
Abstract
Sensory signals are processed by the cerebellum to coordinate movements. Numerous cerebellar functions are thought to require the maintenance of a sensory representation that extends beyond the input signal. Granule cells receive sensory input, but they do not prolong the signal and are thus unlikely to maintain a sensory representation for much longer than the inputs themselves. Unipolar brush cells (UBCs) are excitatory interneurons that project to granule cells and transform sensory input into prolonged increases or decreases in firing, depending on their ON or OFF UBC subtype. Further extension and diversification of the input signal could be produced by UBCs that project to one another, but whether this circuitry exists is unclear. Here we test whether UBCs innervate one another and explore how these small networks of UBCs could transform spiking patterns. We characterized two transgenic mouse lines electrophysiologically and immunohistochemically to confirm that they label ON and OFF UBC subtypes and crossed them together, revealing that ON and OFF UBCs innervate one another. A Brainbow reporter was used to label UBCs of the same ON or OFF subtype with different fluorescent proteins, which showed that UBCs innervate their own subtypes as well. Computational models predict that these feed-forward networks of UBCs extend the length of bursts or pauses and introduce delays-transformations that may be necessary for cerebellar functions from modulation of eye movements to adaptive learning across time scales.
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Affiliation(s)
- Harsh N. Hariani
- Interdisciplinary Graduate Program in Neuroscience
- School of Life Sciences, Arizona State University, Tempe, AZ, 85287
| | - A. Brynn Algstam
- Barrett Honors College
- School of Life Sciences, Arizona State University, Tempe, AZ, 85287
| | - Christian T. Candler
- Interdisciplinary Graduate Program in Neuroscience
- School of Life Sciences, Arizona State University, Tempe, AZ, 85287
| | | | - Jasmeen K. Sidhu
- School of Life Sciences, Arizona State University, Tempe, AZ, 85287
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6
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Huson V, Newman L, Regehr WG. A Continuum of Response Properties across the Population of Unipolar Brush Cells in the Dorsal Cochlear Nucleus. J Neurosci 2023; 43:6035-6045. [PMID: 37507229 PMCID: PMC10451148 DOI: 10.1523/jneurosci.0873-23.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Revised: 07/14/2023] [Accepted: 07/24/2023] [Indexed: 07/30/2023] Open
Abstract
Unipolar brush cells (UBCs) in the cerebellum and dorsal cochlear nucleus (DCN) perform temporal transformations by converting brief mossy fiber bursts into long-lasting responses. In the cerebellar UBC population, mixing inhibition with graded mGluR1-dependent excitation leads to a continuum of temporal responses. In the DCN, it has been thought that mGluR1 contributes little to mossy fiber responses and that there are distinct excitatory and inhibitory UBC subtypes. Here, we investigate UBC response properties using noninvasive cell-attached recordings in the DCN of mice of either sex. We find a continuum of responses to mossy fiber bursts ranging from 100 ms excitation to initial inhibition followed by several seconds of excitation to inhibition lasting for hundreds of milliseconds. Pharmacological interrogation reveals excitatory responses are primarily mediated by mGluR1 Thus, UBCs in both the DCN and cerebellum rely on mGluR1 and have a continuum of response durations. The continuum of responses in the DCN may allow more flexible and efficient temporal processing than can be achieved with distinct excitatory and inhibitory populations.SIGNIFICANCE STATEMENT UBCs are specialized excitatory interneurons in cerebellar-like structures that greatly prolong the temporal responses of mossy fiber inputs. They are thought to help cancel out self-generated signals. In the DCN, the prevailing view was that there are two distinct ON and OFF subtypes of UBCs. Here, we show that instead the UBC population has a continuum of response properties. Many cells show suppression and excitation consecutively, and the response durations vary considerably. mGluR1s are crucial in generating a continuum of responses. To understand how UBCs contribute to temporal processing, it is essential to consider the continuous variations of UBC responses, which have advantages over just having opposing ON/OFF subtypes of UBCs.
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Affiliation(s)
- Vincent Huson
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts 02115
| | - Leannah Newman
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts 02115
| | - Wade G Regehr
- Department of Neurobiology, Harvard Medical School, Boston, Massachusetts 02115
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7
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Liu D, Wang J, Zhou L, Tian E, Chen J, Kong W, Lu Y, Zhang S. Differential Modulation of Cerebellar Flocculus Unipolar Brush Cells during Vestibular Compensation. Biomedicines 2023; 11:biomedicines11051298. [PMID: 37238967 DOI: 10.3390/biomedicines11051298] [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: 03/01/2023] [Revised: 04/19/2023] [Accepted: 04/25/2023] [Indexed: 05/28/2023] Open
Abstract
Vestibular compensation is a natural behavioral recovery process following unilateral vestibular injury. Understanding the mechanism can considerably enhance vestibular disorder therapy and advance the adult central nervous system functional plasticity study after injury. The cerebellum, particularly the flocculonodular lobe, tightly modulates the vestibular nucleus, the center for vestibular compensation; however, it is still unclear if the flocculus on both sides is involved in vestibular compensation. Here we report that the unipolar brush cells (UBCs) in the flocculus are modulated by unilateral labyrinthectomy (UL). UBCs are excitatory interneurons targeting granule cells to provide feedforward innervation to the Purkinje cells, the primary output neurons in the cerebellum. According to the upregulated or downregulated response to the mossy fiber glutamatergic input, UBC can be classified into ON and OFF forms of UBCs. Furthermore, we discovered that the expression of marker genes of ON and OFF UBCs, mGluR1α and calretinin, was increased and decreased, respectively, only in ipsilateral flocculus 4-8 h after UL. According to further immunostaining studies, the number of ON and OFF UBCs was not altered during UL, demonstrating that the shift in marker gene expression level in the flocculus was not caused by the transformation of cell types between UBCs and non-UBCs. These findings imply the importance of ipsilateral flocculus UBCs in the acute response of UL, and ON and OFF UBCs may be involved in vestibular compensation in opposite directions.
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Affiliation(s)
- Dan Liu
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Jun Wang
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Liuqing Zhou
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Institute of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - E Tian
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Jingyu Chen
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Weijia Kong
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Institute of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
| | - Yisheng Lu
- Department of Physiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Sulin Zhang
- Department of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
- Institute of Otorhinolaryngology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China
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8
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Guo C, Huson V, Macosko EZ, Regehr WG. Graded heterogeneity of metabotropic signaling underlies a continuum of cell-intrinsic temporal responses in unipolar brush cells. Nat Commun 2021; 12:5491. [PMID: 34620856 PMCID: PMC8497507 DOI: 10.1038/s41467-021-22893-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 04/02/2021] [Indexed: 02/08/2023] Open
Abstract
Many neuron types consist of populations with continuously varying molecular properties. Here, we show a continuum of postsynaptic molecular properties in three types of neurons and assess the functional correlates in cerebellar unipolar brush cells (UBCs). While UBCs are generally thought to form discrete functional subtypes, with mossy fiber (MF) activation increasing firing in ON-UBCs and suppressing firing in OFF-UBCs, recent work also points to a heterogeneity of response profiles. Indeed, we find a continuum of response profiles that reflect the graded and inversely correlated expression of excitatory mGluR1 and inhibitory mGluR2/3 pathways. MFs coactivate mGluR2/3 and mGluR1 in many UBCs, leading to sequential inhibition-excitation because mGluR2/3-currents are faster. Additionally, we show that DAG-kinase controls mGluR1 response duration, and that graded DAG kinase levels correlate with systematic variation of response duration over two orders of magnitude. These results demonstrate that continuous variations in metabotropic signaling can generate a stable cell-autonomous basis for temporal integration and learning over multiple time scales.
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Affiliation(s)
- Chong Guo
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| | - Vincent Huson
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA
| | - Evan Z Macosko
- Broad Institute of Harvard and MIT, Stanley Center for Psychiatric Research, 450 Main St., Cambridge, MA, USA
| | - Wade G Regehr
- Department of Neurobiology, Harvard Medical School, Boston, MA, USA.
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9
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Guo C, Rudolph S, Neuwirth ME, Regehr WG. Purkinje cell outputs selectively inhibit a subset of unipolar brush cells in the input layer of the cerebellar cortex. eLife 2021; 10:e68802. [PMID: 34369877 PMCID: PMC8352585 DOI: 10.7554/elife.68802] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2021] [Accepted: 07/23/2021] [Indexed: 11/13/2022] Open
Abstract
Circuitry of the cerebellar cortex is regionally and functionally specialized. Unipolar brush cells (UBCs), and Purkinje cell (PC) synapses made by axon collaterals in the granular layer, are both enriched in areas that control balance and eye movement. Here, we find a link between these specializations in mice: PCs preferentially inhibit metabotropic glutamate receptor type 1 (mGluR1)-expressing UBCs that respond to mossy fiber (MF) inputs with long lasting increases in firing, but PCs do not inhibit mGluR1-lacking UBCs. PCs inhibit about 29% of mGluR1-expressing UBCs by activating GABAA receptors (GABAARs) and inhibit almost all mGluR1-expressing UBCs by activating GABAB receptors (GABABRs). PC to UBC synapses allow PC output to regulate the input layer of the cerebellar cortex in diverse ways. Based on optogenetic studies and a small number of paired recordings, GABAAR-mediated feedback is fast and unreliable. GABABR-mediated inhibition is slower and is sufficiently large to strongly influence the input-output transformations of mGluR1-expressing UBCs.
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Affiliation(s)
- Chong Guo
- Department of Neurobiology, Harvard Medical SchoolBostonUnited States
| | - Stephanie Rudolph
- Department of Neurobiology, Harvard Medical SchoolBostonUnited States
| | - Morgan E Neuwirth
- Department of Neurobiology, Harvard Medical SchoolBostonUnited States
| | - Wade G Regehr
- Department of Neurobiology, Harvard Medical SchoolBostonUnited States
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10
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Balmer TS, Borges-Merjane C, Trussell LO. Incomplete removal of extracellular glutamate controls synaptic transmission and integration at a cerebellar synapse. eLife 2021; 10:e63819. [PMID: 33616036 PMCID: PMC7935485 DOI: 10.7554/elife.63819] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Accepted: 02/19/2021] [Indexed: 11/27/2022] Open
Abstract
Synapses of glutamatergic mossy fibers (MFs) onto cerebellar unipolar brush cells (UBCs) generate slow excitatory (ON) or inhibitory (OFF) postsynaptic responses dependent on the complement of glutamate receptors expressed on the UBC's large dendritic brush. Using mouse brain slice recording and computational modeling of synaptic transmission, we found that substantial glutamate is maintained in the UBC synaptic cleft, sufficient to modify spontaneous firing in OFF UBCs and tonically desensitize AMPARs of ON UBCs. The source of this ambient glutamate was spontaneous, spike-independent exocytosis from the MF terminal, and its level was dependent on activity of glutamate transporters EAAT1-2. Increasing levels of ambient glutamate shifted the polarity of evoked synaptic responses in ON UBCs and altered the phase of responses to in vivo-like synaptic activity. Unlike classical fast synapses, receptors at the UBC synapse are virtually always exposed to a significant level of glutamate, which varies in a graded manner during transmission.
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Affiliation(s)
- Timothy S Balmer
- Vollum Institute and Oregon Hearing Research Center, Oregon Health & Science UniversityPortlandUnited States
| | - Carolina Borges-Merjane
- Vollum Institute and Oregon Hearing Research Center, Oregon Health & Science UniversityPortlandUnited States
- Neuroscience Graduate Program, Vollum Institute, Oregon Health & Science UniversityPortlandUnited States
| | - Laurence O Trussell
- Vollum Institute and Oregon Hearing Research Center, Oregon Health & Science UniversityPortlandUnited States
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11
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McDonough A, Elsen GE, Daza RM, Bachleda AR, Pizzo D, DelleTorri OM, Hevner RF. Unipolar (Dendritic) Brush Cells Are Morphologically Complex and Require Tbr2 for Differentiation and Migration. Front Neurosci 2021; 14:598548. [PMID: 33488348 PMCID: PMC7820753 DOI: 10.3389/fnins.2020.598548] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 12/04/2020] [Indexed: 01/21/2023] Open
Abstract
Previous studies demonstrated specific expression of transcription factor Tbr2 in unipolar brush cells (UBCs) of the cerebellum during development and adulthood. To further study UBCs and the role of Tbr2 in their development we examined UBC morphology in transgenic mouse lines (reporter and lineage tracer) and also examined the effects of Tbr2 deficiency in Tbr2 (MGI: Eomes) conditional knock-out (cKO) mice. In Tbr2 reporter and lineage tracer cerebellum, UBCs exhibited more complex morphologies than previously reported including multiple dendrites, bifurcating dendrites, and up to four dendritic brushes. We propose that “dendritic brush cells” (DBCs) may be a more apt nomenclature. In Tbr2 cKO cerebellum, mature UBCs were completely absent. Migration of UBC precursors from rhombic lip to cerebellar cortex and other nuclei was impaired in Tbr2 cKO mice. Our results indicate that UBC migration and differentiation are sensitive to Tbr2 deficiency. To investigate whether UBCs develop similarly in humans as in rodents, we studied Tbr2 expression in mid-gestational human cerebellum. Remarkably, Tbr2+ UBC precursors migrate along the same pathways in humans as in rodent cerebellum and disperse to create the same “fountain-like” appearance characteristic of UBCs exiting the rhombic lip.
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Affiliation(s)
- Ashley McDonough
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, United States
| | - Gina E Elsen
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, United States
| | - Ray M Daza
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, United States.,Department of Pathology, University of California, San Diego, CA, United States
| | - Amelia R Bachleda
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, United States
| | - Donald Pizzo
- Department of Pathology, University of California, San Diego, CA, United States
| | - Olivia M DelleTorri
- California Institute for Regenerative Medicine, California State University San Marcos, San Marcos, CA, United States
| | - Robert F Hevner
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, United States.,Department of Pathology, University of California, San Diego, CA, United States.,Department of Neurological Surgery, University of Washington, Seattle, WA, United States
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12
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An L, Tang Y, Wang D, Jia S, Pei Q, Wang Q, Yu Z, Liu JK. Intrinsic and Synaptic Properties Shaping Diverse Behaviors of Neural Dynamics. Front Comput Neurosci 2020; 14:26. [PMID: 32372936 PMCID: PMC7187274 DOI: 10.3389/fncom.2020.00026] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 03/18/2020] [Indexed: 12/19/2022] Open
Abstract
The majority of neurons in the neuronal system of the brain have a complex morphological structure, which diversifies the dynamics of neurons. In the granular layer of the cerebellum, there exists a unique cell type, the unipolar brush cell (UBC), that serves as an important relay cell for transferring information from outside mossy fibers to downstream granule cells. The distinguishing feature of the UBC is that it has a simple morphology, with only one short dendritic brush connected to its soma. Based on experimental evidence showing that UBCs exhibit a variety of dynamic behaviors, here we develop two simple models, one with a few detailed ion channels for simulation and the other one as a two-variable dynamical system for theoretical analysis, to characterize the intrinsic dynamics of UBCs. The reasonable values of the key channel parameters of the models can be determined by analysis of the stability of the resting membrane potential and the rebound firing properties of UBCs. Considered together with a large variety of synaptic dynamics installed on UBCs, we show that the simple-structured UBCs, as relay cells, can extend the range of dynamics and information from input mossy fibers to granule cells with low-frequency resonance and transfer stereotyped inputs to diverse amplitudes and phases of the output for downstream granule cells. These results suggest that neuronal computation, embedded within intrinsic ion channels and the diverse synaptic properties of single neurons without sophisticated morphology, can shape a large variety of dynamic behaviors to enhance the computational ability of local neuronal circuits.
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Affiliation(s)
- Lingling An
- School of Computer Science and Technology, Xidian University, Xi'an, China
| | - Yuanhong Tang
- School of Computer Science and Technology, Xidian University, Xi'an, China
| | - Doudou Wang
- School of Computer Science and Technology, Xidian University, Xi'an, China
| | - Shanshan Jia
- National Engineering Laboratory for Video Technology, Department of Computer Science and Technology, Peking University, Beijing, China
| | - Qingqi Pei
- School of Computer Science and Technology, Xidian University, Xi'an, China
| | - Quan Wang
- School of Computer Science and Technology, Xidian University, Xi'an, China
| | - Zhaofei Yu
- National Engineering Laboratory for Video Technology, Department of Computer Science and Technology, Peking University, Beijing, China
| | - Jian K Liu
- Centre for Systems Neuroscience, Department of Neuroscience, Psychology and Behaviour, University of Leicester, Leicester, United Kingdom
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13
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Kreko-Pierce T, Boiko N, Harbidge DG, Marcus DC, Stockand JD, Pugh JR. Cerebellar Ataxia Caused by Type II Unipolar Brush Cell Dysfunction in the Asic5 Knockout Mouse. Sci Rep 2020; 10:2168. [PMID: 32034189 PMCID: PMC7005805 DOI: 10.1038/s41598-020-58901-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 01/22/2020] [Indexed: 01/02/2023] Open
Abstract
Unipolar brush cells (UBCs) are excitatory granular layer interneurons in the vestibulocerebellum. Here we assessed motor coordination and balance to investigate if deletion of acid-sensing ion channel 5 (Asic5), which is richly expressed in type II UBCs, is sufficient to cause ataxia. The possible cellular mechanism underpinning ataxia in this global Asic5 knockout model was elaborated using brain slice electrophysiology. Asic5 deletion impaired motor performance and decreased intrinsic UBC excitability, reducing spontaneous action potential firing by slowing maximum depolarization rate. Reduced intrinsic excitability in UBCs was partially compensated by suppression of the magnitude and duration of delayed hyperpolarizing K+ currents triggered by glutamate. Glutamate typically stimulates burst firing subsequent to this hyperpolarization in normal type II UBCs. Burst firing frequency was elevated in knockout type II UBCs because it was initiated from a more depolarized potential compared to normal cells. Findings indicate that Asic5 is important for type II UBC activity and that loss of Asic5 contributes to impaired movement, likely, at least in part, due to altered temporal processing of vestibular input.
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Affiliation(s)
- Tabita Kreko-Pierce
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, 78299, USA
| | - Nina Boiko
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, 78299, USA
| | - Donald G Harbidge
- Department of Anatomy and Physiology, Kansas State University, Manhattan, KS, 66506, USA
| | - Daniel C Marcus
- Department of Anatomy and Physiology, Kansas State University, Manhattan, KS, 66506, USA
| | - James D Stockand
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, 78299, USA.
| | - Jason R Pugh
- Department of Cellular and Integrative Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, 78299, USA
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14
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Balmer TS, Trussell LO. Selective targeting of unipolar brush cell subtypes by cerebellar mossy fibers. eLife 2019; 8:44964. [PMID: 30994458 PMCID: PMC6469928 DOI: 10.7554/elife.44964] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 03/12/2019] [Indexed: 01/26/2023] Open
Abstract
In vestibular cerebellum, primary afferents carry signals from single vestibular end organs, whereas secondary afferents from vestibular nucleus carry integrated signals. Selective targeting of distinct mossy fibers determines how the cerebellum processes vestibular signals. We focused on vestibular projections to ON and OFF classes of unipolar brush cells (UBCs), which transform single mossy fiber signals into long-lasting excitation or inhibition respectively, and impact the activity of ensembles of granule cells. To determine whether these contacts are indeed selective, connectivity was traced back from UBC to specific ganglion cell, hair cell and vestibular organ subtypes in mice. We show that a specialized subset of primary afferents contacts ON UBCs, but not OFF UBCs, while secondary afferents contact both subtypes. Striking anatomical differences were observed between primary and secondary afferents, their synapses, and the UBCs they contact. Thus, each class of UBC functions to transform specific signals through distinct anatomical pathways. While out jogging, you have no trouble keeping your eyes fixed on objects in the distance even though your head and eyes are moving with every step. Humans owe this stability of the visual world partly to a region of the brain called the vestibular cerebellum. From its position underneath the rest of the brain, the vestibular cerebellum detects head motion and then triggers compensatory movements to stabilize the head, body and eyes. The vestibular cerebellum receives sensory input from the body via direct and indirect routes. The direct input comes from five structures within the inner ear, each of which detects movement of the head in one particular direction. The indirect input travels to the cerebellum via the brainstem, which connects the brain with the spinal cord. The indirect input contains information on head movements in multiple directions combined with input from other senses such as vision. By studying the mouse brain, Balmer and Trussell have now mapped the direct and indirect circuits that carry sensory information to the vestibular cerebellum. Both types of input activate cells within the vestibular cerebellum called unipolar brush cells (UBCs). There are two types of UBCs: ON and OFF. Direct sensory input from the inner ear activates only ON UBCs. These cells respond to the arrival of sensory input by increasing their activity. Indirect input from the brainstem activates both ON UBCs and OFF UBCs. The latter respond to the input by decreasing their activity. The vestibular cerebellum thus processes direct and indirect inputs via segregated pathways containing different types of UBCs. The next step in understanding how the cerebellum maintains a stable visual world is to identify the circuitry beyond the UBCs. Understanding these circuits will ultimately provide insights into balance disorders, such as vertigo.
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Affiliation(s)
- Timothy S Balmer
- Vollum Institute and Oregon Hearing Research Center, Oregon Health and Science University, Portland, United States
| | - Laurence O Trussell
- Vollum Institute and Oregon Hearing Research Center, Oregon Health and Science University, Portland, United States
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15
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Leto K, Arancillo M, Becker EBE, Buffo A, Chiang C, Ding B, Dobyns WB, Dusart I, Haldipur P, Hatten ME, Hoshino M, Joyner AL, Kano M, Kilpatrick DL, Koibuchi N, Marino S, Martinez S, Millen KJ, Millner TO, Miyata T, Parmigiani E, Schilling K, Sekerková G, Sillitoe RV, Sotelo C, Uesaka N, Wefers A, Wingate RJT, Hawkes R. Consensus Paper: Cerebellar Development. CEREBELLUM (LONDON, ENGLAND) 2016; 15:789-828. [PMID: 26439486 PMCID: PMC4846577 DOI: 10.1007/s12311-015-0724-2] [Citation(s) in RCA: 256] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The development of the mammalian cerebellum is orchestrated by both cell-autonomous programs and inductive environmental influences. Here, we describe the main processes of cerebellar ontogenesis, highlighting the neurogenic strategies used by developing progenitors, the genetic programs involved in cell fate specification, the progressive changes of structural organization, and some of the better-known abnormalities associated with developmental disorders of the cerebellum.
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Affiliation(s)
- Ketty Leto
- Department of Neuroscience Rita Levi Montalcini, University of Turin, via Cherasco 15, 10026, Turin, Italy.
- Neuroscience Institute Cavalieri-Ottolenghi, University of Turin, Regione Gonzole 10, 10043, Orbassano, Torino, Italy.
| | - Marife Arancillo
- Departments of Pathology & Immunology and Neuroscience, Baylor College of Medicine, Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA
| | - Esther B E Becker
- Medical Research Council Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, OX1 3PT, UK
| | - Annalisa Buffo
- Department of Neuroscience Rita Levi Montalcini, University of Turin, via Cherasco 15, 10026, Turin, Italy
- Neuroscience Institute Cavalieri-Ottolenghi, University of Turin, Regione Gonzole 10, 10043, Orbassano, Torino, Italy
| | - Chin Chiang
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, 4114 MRB III, Nashville, TN, 37232, USA
| | - Baojin Ding
- Department of Microbiology and Physiological Systems and Program in Neuroscience, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA, 01605-2324, USA
| | - William B Dobyns
- Seattle Children's Research Institute, Center for Integrative Brain Research, Seattle, WA, USA
- Department of Pediatrics, Genetics Division, University of Washington, Seattle, WA, USA
| | - Isabelle Dusart
- Sorbonne Universités, Université Pierre et Marie Curie Univ Paris 06, Institut de Biologie Paris Seine, France, 75005, Paris, France
- Centre National de la Recherche Scientifique, CNRS, UMR8246, INSERM U1130, Neuroscience Paris Seine, France, 75005, Paris, France
| | - Parthiv Haldipur
- Seattle Children's Research Institute, Center for Integrative Brain Research, Seattle, WA, USA
| | - Mary E Hatten
- Laboratory of Developmental Neurobiology, The Rockefeller University, New York, NY, 10065, USA
| | - Mikio Hoshino
- Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo, 187-8502, Japan
| | - Alexandra L Joyner
- Developmental Biology Program, Sloan Kettering Institute, New York, NY, 10065, USA
| | - Masanobu Kano
- Department of Neurophysiology, Graduate School of Medicine, The University of Tokyo, Tokyo, 113-0033, Japan
| | - Daniel L Kilpatrick
- Department of Microbiology and Physiological Systems and Program in Neuroscience, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA, 01605-2324, USA
| | - Noriyuki Koibuchi
- Department of Integrative Physiology, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma, 371-8511, Japan
| | - Silvia Marino
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, 4 Newark Street, London, E1 2AT, UK
| | - Salvador Martinez
- Department Human Anatomy, IMIB-Arrixaca, University of Murcia, Murcia, Spain
| | - Kathleen J Millen
- Seattle Children's Research Institute, Center for Integrative Brain Research, Seattle, WA, USA
| | - Thomas O Millner
- Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, 4 Newark Street, London, E1 2AT, UK
| | - Takaki Miyata
- Department of Anatomy and Cell Biology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Elena Parmigiani
- Department of Neuroscience Rita Levi Montalcini, University of Turin, via Cherasco 15, 10026, Turin, Italy
- Neuroscience Institute Cavalieri-Ottolenghi, University of Turin, Regione Gonzole 10, 10043, Orbassano, Torino, Italy
| | - Karl Schilling
- Anatomie und Zellbiologie, Anatomisches Institut, Rheinische Friedrich-Wilhelms-Universität, Bonn, Germany
| | - Gabriella Sekerková
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - Roy V Sillitoe
- Departments of Pathology & Immunology and Neuroscience, Baylor College of Medicine, Jan and Dan Duncan Neurological Research Institute of Texas Children's Hospital, 1250 Moursund Street, Suite 1325, Houston, TX, 77030, USA
| | - Constantino Sotelo
- Institut de la Vision, UPMC Université de Paris 06, Paris, 75012, France
| | - Naofumi Uesaka
- Department of Neurophysiology, Graduate School of Medicine, The University of Tokyo, Tokyo, 113-0033, Japan
| | - Annika Wefers
- Center for Neuropathology, Ludwig-Maximilians-University, Munich, Germany
| | - Richard J T Wingate
- MRC Centre for Developmental Neurobiology, King's College London, London, UK
| | - Richard Hawkes
- Department of Cell Biology & Anatomy and Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, T2N 4NI, AB, Canada
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16
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Zampini V, Liu JK, Diana MA, Maldonado PP, Brunel N, Dieudonné S. Mechanisms and functional roles of glutamatergic synapse diversity in a cerebellar circuit. eLife 2016; 5. [PMID: 27642013 PMCID: PMC5074806 DOI: 10.7554/elife.15872] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 09/17/2016] [Indexed: 02/04/2023] Open
Abstract
Synaptic currents display a large degree of heterogeneity of their temporal characteristics, but the functional role of such heterogeneities remains unknown. We investigated in rat cerebellar slices synaptic currents in Unipolar Brush Cells (UBCs), which generate intrinsic mossy fibers relaying vestibular inputs to the cerebellar cortex. We show that UBCs respond to sinusoidal modulations of their sensory input with heterogeneous amplitudes and phase shifts. Experiments and modeling indicate that this variability results both from the kinetics of synaptic glutamate transients and from the diversity of postsynaptic receptors. While phase inversion is produced by an mGluR2-activated outward conductance in OFF-UBCs, the phase delay of ON UBCs is caused by a late rebound current resulting from AMPAR recovery from desensitization. Granular layer network modeling indicates that phase dispersion of UBC responses generates diverse phase coding in the granule cell population, allowing climbing-fiber-driven Purkinje cell learning at arbitrary phases of the vestibular input. DOI:http://dx.doi.org/10.7554/eLife.15872.001 Whether walking, riding a bicycle or simply standing still, we continually adjust our posture in small ways to prevent ourselves from falling. Our sense of balance depends on a set of structures inside the inner ear called the vestibular system. These structures detect movements of the head and relay this information to the brain in the form of electrical signals. A brain area called the vestibulo-cerebellum then combines these signals with sensory input from the eyes and muscles, before sending out further signals to trigger any adjustments necessary for balance. One of the main cell types within the vestibulo-cerebellum is the unipolar brush cell (or UBC for short). UBCs pass on signals to another type of neuron called Purkinje cells, which support the learning of motor skills such as adjusting posture. Zampini, Liu et al. set out to test the idea that UBCs transform inputs from the vestibular system into a format that makes it easier for cerebellar Purkinje cells to drive this kind of learning. First, recordings from slices of rodent brain revealed that UBCs respond in highly variable ways to vestibular input, with both the size and timing of responses varying between cells. This is because vestibular signals trigger the release of a chemical messenger called glutamate onto UBCs, but UBCs possess a variety of different types of glutamate receptors. Vestibular input therefore activates distinct signaling cascades from one UBC to the next. According to a computer model, this variability in UBC responses ensures that a subset of UBCs will always be active at any point during vestibular input. This in turn means that Purkinje cells can fire at any stage of a movement, which boosts the learning of motor skills. The next steps will be to test this hypothesis using mutant mice that lack specific receptor subtypes in UBCs or UBCs completely. A further challenge for the future will be to build a computer model of the vestibulo-cerebellar system that includes all of its component cell types. DOI:http://dx.doi.org/10.7554/eLife.15872.002
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Affiliation(s)
- Valeria Zampini
- Institut de Biologie de l'ENS, Ecole Normale Supérieure, Paris, France.,Inserm, U1024, Paris, France.,CNRS, UMR 8197, Paris, France
| | - Jian K Liu
- Neurosciences Federation, Université Paris Descartes, Paris, France.,Department of Ophthalmology, University Medical Center Goettingen, Goettingen, Germany.,Bernstein Center for Computational Neuroscience, Göttingen, Germany
| | - Marco A Diana
- Institut de Biologie de l'ENS, Ecole Normale Supérieure, Paris, France.,Inserm, U1024, Paris, France.,CNRS, UMR 8197, Paris, France
| | - Paloma P Maldonado
- Institut de Biologie de l'ENS, Ecole Normale Supérieure, Paris, France.,Inserm, U1024, Paris, France.,CNRS, UMR 8197, Paris, France
| | - Nicolas Brunel
- Neurosciences Federation, Université Paris Descartes, Paris, France.,Department of Statistics and Neurobiology, University of Chicago, Chicago, United States
| | - Stéphane Dieudonné
- Institut de Biologie de l'ENS, Ecole Normale Supérieure, Paris, France.,Inserm, U1024, Paris, France.,CNRS, UMR 8197, Paris, France
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Hensbroek RA, Ruigrok TJH, van Beugen BJ, Maruta J, Simpson JI. Visuo-vestibular information processing by unipolar brush cells in the rabbit flocculus. THE CEREBELLUM 2016; 14:578-83. [PMID: 26280650 PMCID: PMC4612327 DOI: 10.1007/s12311-015-0710-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The unipolar brush cell (UBC) is a glutamatergic granular layer interneuron that is predominantly located in the vestibulocerebellum and parts of the vermis. In rat and rabbit, we previously found using juxtacellular labeling combined with spontaneous activity recording that cells with highly regular spontaneous activity belong to the UBC category. Making use of this signature, we recorded from floccular UBCs in both anesthetized and awake rabbits while delivering visuo-vestibular stimulation by using sigmoidal rotation of the whole animal. In the anesthetized rabbit, the activity of the presumed UBC units displayed a wide variety of modulation profiles that could be related to aspects of head velocity or acceleration. These modulation profiles could also be found in the awake rabbit where, in addition, they could also carry an eye position signal. Furthermore, units in the awake rabbit could demonstrate rather long response latencies of up to 0.5 s. We suggest that the UBCs recorded in this study mostly belong to the type I UBC category (calretinin-positive) and that they can play diverse roles in floccular visuo-vestibular information processing, such as transformation of velocity-related signals to acceleration-related signals.
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Affiliation(s)
- Robert A Hensbroek
- Department of Neuroscience & Physiology, New York University Medical School, New York, NY, 10016, USA
| | - Tom J H Ruigrok
- Department of Neuroscience, Erasmus MC Rotterdam, 3000 CA, Rotterdam, Netherlands.
| | | | - Jun Maruta
- Brain Trauma Foundation, 1 Broadway, New York, NY, 10004, USA
| | - John I Simpson
- Department of Neuroscience & Physiology, New York University Medical School, New York, NY, 10016, USA
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18
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Commentary on "E. Mugnaini and A. Floris, the unipolar brush cell: a neglected neuron of the mammalian cerebellar cortex. J Comp Neurol, 339:174-180, 1994". THE CEREBELLUM 2016; 14:484-6. [PMID: 25822473 DOI: 10.1007/s12311-015-0660-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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19
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α-Synuclein expression in the mouse cerebellum is restricted to VGluT1 excitatory terminals and is enriched in unipolar brush cells. THE CEREBELLUM 2016; 14:516-27. [PMID: 25917213 DOI: 10.1007/s12311-015-0673-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
α-Synuclein has a crucial role in synaptic vesicle release and synaptic membrane recycling. Although its general expression pattern has been described in the cerebellum, the precise cerebellar structures where α-synuclein is localized are poorly understood. To address this question, we used α-synuclein immunohistochemistry in adult mice cerebellar sections. We found that α-synuclein labels glutamatergic but not glycinergic and GABAergic synaptic terminals in the molecular and granule cell layers. α-Synuclein was preferentially expressed in parallel and mossy fiber synaptic terminals that also express vesicular glutamate transporter 1 (VGluT1), while it was not detected in VGluT2-positive climbing fibers. α-Synuclein was particularly enriched in lobules IX and X, a region known to contain a high density of unipolar brush cells (UBCs). To elucidate whether the α-synuclein-positive mossy fibers belong to UBCs, we double-labeled cerebellar sections with antibodies to α-synuclein and UBC-type-specific markers (calretinin for type I and metabotropic glutamate receptor 1α (mGluR1α) for type II UBCs) and took advantage of organotypic cerebellar cultures (in which all mossy fibers are UBC axons) and moonwalker mice (in which almost all UBCs are ablated) and found that both type I and type II UBCs express α-synuclein. In moonwalker mutant cerebella, the α-synuclein/VGluT1 immunolabeling showed a dramatic decrease in the vestibulocerebellum that correlated with the absence of UBC. α-Synuclein appears to be an excellent marker for intrinsic mossy fibers of the VGluT1 subset in conjunction with UBCs of both subtypes.
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20
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Editorial on the honorary cerebellum issue for the retirement of Enrico Mugnaini. THE CEREBELLUM 2016; 14:487-90. [PMID: 26450590 DOI: 10.1007/s12311-015-0729-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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21
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Takayasu Y, Shino M, Nikkuni O, Yoshida Y, Furuya N, Chikamatsu K. Oxygen-glucose deprivation increases firing of unipolar brush cells and enhances spontaneous EPSCs in Purkinje cells in the vestibulo-cerebellum. Neurosci Res 2015; 106:1-11. [PMID: 26535811 DOI: 10.1016/j.neures.2015.10.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Revised: 09/26/2015] [Accepted: 10/23/2015] [Indexed: 11/19/2022]
Abstract
Unipolar brush cells (UBCs) are excitatory interneurons in the granular layer of the cerebellar cortex, which are predominantly distributed in the vestibulo-cerebellar region. The unique firing properties and synaptic connections of UBCs may underlie lobular heterogeneity of excitability in the granular layer and the susceptibility to ischemia-induced excitotoxicity. In this study, we investigated the effects of oxygen-glucose deprivation (OGD) on the firing properties of UBCs and granule cells and spontaneous excitatory postsynaptic currents (sEPSCs) of Purkinje cells using whole-cell recordings. Short-term OGD induced increases in spontaneous firing of UBCs by causing membrane depolarization via the activation of NMDA receptors. UBC firing indirectly affected Purkinje cells by altering parallel fiber inputs of a subset granule cells, resulting in a marked increase in sEPSCs in Purkinje cells in vestibulo-cerebellar lobules IX-X, but not in lobules IV-VI, which have fewer UBCs. Similarly, the frequency and amplitude of sEPSCs in Purkinje cells were significantly greater in lobules IX-X than in IV-VI, even in control conditions. These results reveal that UBCs play key roles in regulating local excitability in the granular layer, resulting in lobular heterogeneity in the susceptibility to ischemic insult in the cerebellum.
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Affiliation(s)
- Yukihiro Takayasu
- Department of Otolaryngology-Head and Neck Surgery, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan.
| | - Masato Shino
- Department of Otolaryngology-Head and Neck Surgery, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan
| | - Osamu Nikkuni
- Department of Otolaryngology-Head and Neck Surgery, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan
| | - Yukari Yoshida
- Gunma University Heavy Ion Medical Center, Maebashi, Gunma 371-8511, Japan
| | - Nobuhiko Furuya
- Department of Otolaryngology-Head and Neck Surgery, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan
| | - Kazuaki Chikamatsu
- Department of Otolaryngology-Head and Neck Surgery, Gunma University Graduate School of Medicine, Maebashi, Gunma 371-8511, Japan
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22
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Borges-Merjane C, Trussell LO. ON and OFF unipolar brush cells transform multisensory inputs to the auditory system. Neuron 2015; 85:1029-42. [PMID: 25741727 DOI: 10.1016/j.neuron.2015.02.009] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 12/27/2014] [Accepted: 01/22/2015] [Indexed: 12/15/2022]
Abstract
Unipolar brush cells (UBCs) of the dorsal cochlear nucleus (DCN) and vestibular cerebellar cortex receive glutamatergic mossy fiber input on an elaborate brush-like dendrite. Two subtypes of UBC have been established based on immunohistochemical markers and physiological profiles, but the relation of these subtypes to the response to mossy fiber input is not clear. We examined the synaptic physiology of auditory UBCs in mouse brain slices, identifying two response profiles, and correlated each with a specific UBC subtype. One subtype had a striking biphasic excitatory response mediated by AMPAR and mGluR1α. The second was mGluR1α negative and was dominated by a strongly inhibitory outward K(+) current. These two subtypes upregulated or downregulated spontaneous firing, respectively. By analogy to the retina, we propose that UBCs comprise ON and OFF cells with respect to their response to glutamatergic input and may therefore provide distinct parallel processing of multisensory input to their targets.
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Affiliation(s)
- Carolina Borges-Merjane
- Neuroscience Graduate Program, Vollum Institute, Oregon Health and Science University, Portland, OR 97239, USA; Vollum Institute and Oregon Hearing Research Center, Oregon Health and Science University, Portland, OR 97239, USA
| | - Laurence O Trussell
- Vollum Institute and Oregon Hearing Research Center, Oregon Health and Science University, Portland, OR 97239, USA.
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23
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Redefining the cerebellar cortex as an assembly of non-uniform Purkinje cell microcircuits. Nat Rev Neurosci 2015; 16:79-93. [PMID: 25601779 DOI: 10.1038/nrn3886] [Citation(s) in RCA: 192] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The adult mammalian cerebellar cortex is generally assumed to have a uniform cytoarchitecture. Differences in cerebellar function are thought to arise primarily through distinct patterns of input and output connectivity rather than as a result of variations in cortical microcircuitry. However, evidence from anatomical, physiological and genetic studies is increasingly challenging this orthodoxy, and there are now various lines of evidence indicating that the cerebellar cortex is not uniform. Here, we develop the hypothesis that regional differences in properties of cerebellar cortical microcircuits lead to important differences in information processing.
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Baizer JS, Wong KM, Paolone NA, Weinstock N, Salvi RJ, Manohar S, Witelson SF, Baker JF, Sherwood CC, Hof PR. Laminar and neurochemical organization of the dorsal cochlear nucleus of the human, monkey, cat, and rodents. Anat Rec (Hoboken) 2014; 297:1865-84. [PMID: 25132345 DOI: 10.1002/ar.23000] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2013] [Accepted: 06/09/2014] [Indexed: 01/02/2023]
Abstract
The dorsal cochlear nucleus (DCN) is a brainstem structure that receives input from the auditory nerve. Many studies in a diversity of species have shown that the DCN has a laminar organization and identifiable neuron types with predictable synaptic relations to each other. In contrast, studies on the human DCN have found a less distinct laminar organization and fewer cell types, although there has been disagreement among studies in how to characterize laminar organization and which of the cell types identified in other animals are also present in humans. We have reexamined DCN organization in the human using immunohistochemistry to analyze the expression of several proteins that have been useful in delineating the neurochemical organization of other brainstem structures in humans: nonphosphorylated neurofilament protein (NPNFP), nitric oxide synthase (nNOS), and three calcium-binding proteins. The results for humans suggest a laminar organization with only two layers, and the presence of large projection neurons that are enriched in NPNFP. We did not observe evidence in humans of the inhibitory interneurons that have been described in the cat and rodent DCN. To compare humans and other animals directly we used immunohistochemistry to examine the DCN in the macaque monkey, the cat, and three rodents. We found similarities between macaque monkey and human in the expression of NPNFP and nNOS, and unexpected differences among species in the patterns of expression of the calcium-binding proteins.
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Affiliation(s)
- Joan S Baizer
- Department of Physiology and Biophysics, University at Buffalo, Buffalo, New York
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25
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Boiko N, Kucher V, Wang B, Stockand JD. Restrictive expression of acid-sensing ion channel 5 (asic5) in unipolar brush cells of the vestibulocerebellum. PLoS One 2014; 9:e91326. [PMID: 24663811 PMCID: PMC3963869 DOI: 10.1371/journal.pone.0091326] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Accepted: 02/07/2014] [Indexed: 12/23/2022] Open
Abstract
Acid-sensing ion channels (Asic) are ligand-gated ion channels in the Degenerin/Epithelial Na+ channel (Deg/ENaC) family. Asic proteins are richly expressed in mammalian neurons. Mammals express five Asic genes: Asic1-5. The gene product of Asic5 is an orphan member of the family about which little is known. To investigate Asic5 expression, we created an Asic5 reporter mouse. We find that Asic5 is chiefly expressed in the brain in the cerebellum, specifically in the ventral uvula and nodulus of the vestibulocerebellum. Here, Asic5 is restrictively expressed in a subset of interneurons in the granular layer. The locale, distinctive shape and immunohistochemical properties of these Asic5-expressing interneurons identify them as unipolar brush cells (UBC). Asic5 is richly expressed in a subset of UBCs that also express the metabotropic glutamate receptor 1α (mGluR1α) but not those that express calretinin. Results from single cell RT-PCR and electrophysiological examination of these cells are consistent with this identity. Such observations are consistent with Asic5 playing a key role in the physiology of UBCs and in the function of the vestibulocerebellum.
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Affiliation(s)
- Nina Boiko
- Department of Physiology, University of Texas Health Science Center, San Antonio, Texas, United States of America
| | - Volodymyr Kucher
- Department of Physiology, University of Texas Health Science Center, San Antonio, Texas, United States of America
| | - Bin Wang
- Department of Physiology, University of Texas Health Science Center, San Antonio, Texas, United States of America
| | - James D. Stockand
- Department of Physiology, University of Texas Health Science Center, San Antonio, Texas, United States of America
- * E-mail:
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26
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Early onset of ataxia in moonwalker mice is accompanied by complete ablation of type II unipolar brush cells and Purkinje cell dysfunction. J Neurosci 2014; 33:19689-94. [PMID: 24336732 DOI: 10.1523/jneurosci.2294-13.2013] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Transient receptor potential "canonical" cation channels (TRPC) are involved in many cellular activities, including neuronal synaptic transmission. These channels couple lipid metabolism, calcium homeostasis, and electrophysiological properties as they are calcium permeable and activated through the phospholipase C pathway and by diacylglycerol. The TRPC3 subunit is abundantly expressed in Purkinje cells (PCs), where it mediates slow metabotropic glutamate receptor-mediated synaptic responses. Recently, it has been shown that heterozygous moonwalker mice, which are a model of cerebellar ataxia, carry a dominant gain-of-function mutation (T635A) in the TRPC3 gene. This mutation leads to PC loss and dysmorphism, which have been suggested to cause the ataxia. However, the ataxic phenotype is present from a very early stage (before weaning), whereas PC loss does not appear until several months of age. Here we show that another class of cerebellar neurons, the type II unipolar brush cells (UBCs), express functional TRPC3 channels; intriguingly, these cells are ablated in moonwalker mice by 1 month of age. Additionally, we show that in moonwalker mice, intrinsic excitability of PCs is altered as early as 3 weeks after birth. We suggest that this altered excitability and the TRPC3-mediated loss of type II UBCs may both contribute to the ataxic phenotype of these mice and that different calcium handling in PCs and type II UBCs may account for the dramatic differences in sensitivity to the moonwalker mutation between these cell types.
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Affiliation(s)
| | - Richard Hawkes
- Department of Cell Biology and Anatomy, Genes and Development Research Group and Hotchkiss Brain Institute, Faculty of Medicine, University of Calgary
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Kim JA, Sekerková G, Mugnaini E, Martina M. Electrophysiological, morphological, and topological properties of two histochemically distinct subpopulations of cerebellar unipolar brush cells. THE CEREBELLUM 2013; 11:1012-25. [PMID: 22528965 DOI: 10.1007/s12311-012-0380-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Unipolar brush cells (UBCs) are excitatory cerebellar granular layer interneurons whose brush-like dendrites receive one-to-one mossy fiber inputs. Subclasses of UBCs differ primarily by expressing metabotropic glutamate receptor (mGluR) 1α or calretinin. We used GENSAT Tg(Grp-EGFP) BAC transgenic mice, which selectively express enhanced green fluorescent protein (EGFP) in mGluR1α-positive UBCs to compare the functional properties of the two subclasses. Compared to EGFP-negative UBCs, which include the calretinin-positive cells, EGFP-positive UBCs had smaller somata (area 48 vs 63 μm(2)), lower specific membrane resistance (6.4 vs. 13.7 KΩ cm(2)), were less prone to intrinsic firing, and showed more irregular firing (in cell-attached ~49 % were firing vs. ~88 %, and the CV was 0.53 vs. 0.32 for EGFP-negative cells). Some of these differences are attributable to higher density of background K(+) currents in EGFP-positive cells (at -120 mV, the barium-sensitive current was 94 vs. 37 pA in EGFP-negative cells); Ih, on the contrary, was more abundantly expressed in EGFP-negative cells (at -140 mV, it was -122 vs. -54 pA in EGFP-positive neurons); furthermore, while group II mGluR modulation of the background potassium current in EGFP-negative UBCs was maintained after intracellular dialysis, mGluR modulation in EGFP-positive UBCs was lost in whole-cell recordings. Finally, cell-attached firing was reversibly abolished by the GABA(B) activation in EGFP-positive, but not in EGFP-negative UBCs. Immunohistochemistry showed that EGFP-negative UBCs express GIRK2 at high density, while mGluR1α UBCs are GIRK2 negative, suggesting that GIRK2 mediates the mGluR-sensitive current in EGFP-negative UBCs. These data suggest that the two subclasses perform different functions in the cerebellar microcircuits.
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Affiliation(s)
- Jin-Ah Kim
- Department of Physiology, Northwestern University, Feinberg School of Medicine, 303 E. Chicago Avenue, Chicago, IL, 60611, USA
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29
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Sekerková G, Watanabe M, Martina M, Mugnaini E. Differential distribution of phospholipase C beta isoforms and diaglycerol kinase-beta in rodents cerebella corroborates the division of unipolar brush cells into two major subtypes. Brain Struct Funct 2013; 219:719-49. [PMID: 23503970 DOI: 10.1007/s00429-013-0531-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Accepted: 02/19/2013] [Indexed: 11/26/2022]
Abstract
Sublineage diversification of specific neural cell classes occurs in complex as well as simply organized regions of the central and peripheral nervous systems; the significance of the phenomenon, however, remains insufficiently understood. The unipolar brush cells (UBCs) are glutamatergic cerebellar interneurons that occur at high density in vestibulocerebellum. As they are classified into subsets that differ in chemical phenotypes, intrinsic properties, and lobular distribution, they represent a valuable neuronal model to study subclass diversification. In this study, we show that cerebellar UBCs of adult rats and mice form two subclasses-type I and type II UBCs-defined by somatodendritic expression of calretinin (CR), mGluR1α, phospholipases PLCβ1 and PLCβ4, and diacylglycerol kinase-beta (DGKβ). We demonstrate that PLCβ1 is associated only with the CR(+) type I UBCs, while PLCβ4 and DGKβ are exclusively present in mGluR1α(+) type II UBCs. Notably, all PLCβ4(+) UBCs, representing about 2/3 of entire UBC population, also express mGluR1α. Furthermore, our data show that the sum of CR(+) type I UBCs and mGluR1α(+) type II UBCs accounts for the entire UBC class identified with Tbr2 immunolabeling. The two UBC subtypes also show a very different albeit somehow overlapping topographical distribution as illustrated by detailed cerebellar maps in this study. Our data not only complement and extend the previous knowledge on the diversity and subclass specificity of the chemical phenotypes within the UBC population, but also provide a new angle to the understanding of the signaling networks in type I and type II UBCs.
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Affiliation(s)
- Gabriella Sekerková
- Department of Cellular and Molecular Biology, Feinberg School of Medicine, Northwestern University, 5-465 Searle bldg. 320 E. Superior str, Chicago, IL, 60611, USA,
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Consalez GG, Hawkes R. The compartmental restriction of cerebellar interneurons. Front Neural Circuits 2013; 6:123. [PMID: 23346049 PMCID: PMC3551280 DOI: 10.3389/fncir.2012.00123] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Accepted: 12/26/2012] [Indexed: 11/13/2022] Open
Abstract
The Purkinje cells (PC's) of the cerebellar cortex are subdivided into multiple different molecular phenotypes that form an elaborate array of parasagittal stripes. This array serves as a scaffold around which afferent topography is organized. The ways in which cerebellar interneurons may be restricted by this scaffolding are less well-understood. This review begins with a brief survey of cerebellar topography. Next, it reviews the development of stripes in the cerebellum with a particular emphasis on the embryological origins of cerebellar interneurons. These data serve as a foundation to discuss the hypothesis that cerebellar compartment boundaries also restrict cerebellar interneurons, both excitatory [granule cells, unipolar brush cells (UBCs)] and inhibitory (e.g., Golgi cells, basket cells). Finally, it is proposed that the same PC scaffold that restricts afferent terminal fields to stripes may also act to organize cerebellar interneurons.
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Affiliation(s)
- G Giacomo Consalez
- Division of Neuroscience, San Raffaele Scientific Institute Milan, Italy
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31
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Conserved cellular distribution of the glutamate receptors GluA2/3, mGlu1a and mGlu2/3 in isolated cultures of rat cerebellum. J Chem Neuroanat 2012; 45:26-35. [DOI: 10.1016/j.jchemneu.2012.07.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Revised: 06/15/2012] [Accepted: 07/01/2012] [Indexed: 01/23/2023]
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32
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Toledano A, Alvarez MI, Monleón E, Toledano-Díaz A, Badiola JJ, Monzón M. Changes induced by natural scrapie in the calretinin-immunopositive cells and fibres of the sheep cerebellar cortex. THE CEREBELLUM 2012; 11:593-604. [PMID: 22116659 DOI: 10.1007/s12311-011-0335-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Calretinin (CR)-immunopositive cells and fibres in the cerebellar cortex (vermal archicerebellum and neocerebellum) of scrapie-affected, ARQ/ARQ, Rasa Aragonesa breed sheep were studied in comparison with healthy, young and aged, ARQ/ARQ, Rasa Aragonesa animals and with Manchega breed sheep. The scrapie-affected sheep showed signs of both cellular involution and hypertrophic/hyperimmunoreactive responses in all neuronal subtypes; the distribution of the neuronal subtypes in the archi- and neocerebellum, however, did not change compared with controls. The results suggest that the different CR expression and/or CR content of cerebellar cortical neurons in scrapie-affected sheep are more related to their specific functions than any neuroprotective response. The reduction in the cell density of some CR-immunopositive neuronal subsets (i.e. unipolar brush cells) is contradictory to the supposed neuroprotective role of the calcium binding protein CR. However, the hyperimmunoreactivity of many CR-immunopositive neuronal subsets (e.g. the Purkinje cells) suggests the involvement of an over-expression of CR (transitory or restricted to selected neurons) as an adaptative mechanism to fight against the neurodegeneration caused by this prion disease. The changes in the number of immunopositive cells and the hypertrophic/hyperimmunoreactive response seen in scrapie-affected and aged sheep suggests that some different and some similar mechanisms are at work in this disease and aging.
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Gilbert EA, Lim YH, Vickaryous MK, Armstrong CL. Heterochronic protein expression patterns in the developing embryonic chick cerebellum. Anat Rec (Hoboken) 2012; 295:1669-82. [PMID: 22865685 DOI: 10.1002/ar.22544] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2012] [Revised: 06/12/2012] [Accepted: 07/11/2012] [Indexed: 12/18/2022]
Abstract
The advantages of the embryonic chick as a model for studying neural development range from the relatively low cost of fertilized eggs to the rapid rate of development. We investigated in ovo cerebellar development in the chick, which has a nearly identical embryonic period as the mouse (19-22 days). We focused on three antigens: Calbindin (CB), Zebrin II (ZII), and Calretinin (CR), and our results demonstrate asynchronous expression patterns during cerebellar development. Presumptive CB+ Purkinje cells are first observed at embryonic day (E)10 in clusters in posterior cerebellum. At E12, corresponding with global expression of CB across the cerebellum, Purkinje cells began to express ZII. By E14-E16, Purkinje cells disperse into a monolayer and develop a pattern of alternating immunopositive and immunonegative ZII stripes. CR is initially expressed by clusters of presumptive Purkinje cells in the nodular zone at E8. However, this expression is transient and at later stages, CR is largely confined to the granule and molecular layers. Before hatch (E18-E20), Purkinje cells adopt a morphologically mature phenotype with complex dendritic arborizations. Comparing this data to that seen in mice, we found that the sequence of Purkinje cell formation, protein expression, and development is similar in both species, but these events consistently begin ∼5-7 days earlier in the precocial chick cerebellum, suggesting an important role for heterochrony in neurodevelopment.
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Affiliation(s)
- E A Gilbert
- Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, 50 Stone Road, Guelph, Ontario, Canada
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NMDA receptors with incomplete Mg²⁺ block enable low-frequency transmission through the cerebellar cortex. J Neurosci 2012; 32:6878-93. [PMID: 22593057 DOI: 10.1523/jneurosci.5736-11.2012] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The cerebellar cortex coordinates movements and maintains balance by modifying motor commands as a function of sensory-motor context, which is encoded by mossy fiber (MF) activity. MFs exhibit a wide range of activity, from brief precisely timed high-frequency bursts, which encode discrete variables such as whisker stimulation, to low-frequency sustained rate-coded modulation, which encodes continuous variables such as head velocity. While high-frequency MF inputs have been shown to activate granule cells (GCs) effectively, much less is known about sustained low-frequency signaling through the GC layer, which is impeded by a hyperpolarized resting potential and strong GABA(A)-mediated tonic inhibition of GCs. Here we have exploited the intrinsic MF network of unipolar brush cells to activate GCs with sustained low-frequency asynchronous MF inputs in rat cerebellar slices. We find that low-frequency MF input modulates the intrinsic firing of Purkinje cells, and that this signal transmission through the GC layer requires synaptic activation of Mg²⁺-block-resistant NMDA receptors (NMDARs) that are likely to contain the GluN2C subunit. Slow NMDAR conductances sum temporally to contribute approximately half the MF-GC synaptic charge at hyperpolarized potentials. Simulations of synaptic integration in GCs show that the NMDAR and slow spillover-activated AMPA receptor (AMPAR) components depolarize GCs to a similar extent. Moreover, their combined depolarizing effect enables the fast quantal AMPAR component to trigger action potentials at low MF input frequencies. Our results suggest that the weak Mg²⁺ block of GluN2C-containing NMDARs enables transmission of low-frequency MF signals through the input layer of the cerebellar cortex.
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Mixed inhibitory synaptic balance correlates with glutamatergic synaptic phenotype in cerebellar unipolar brush cells. J Neurosci 2012; 32:4632-44. [PMID: 22457509 DOI: 10.1523/jneurosci.5122-11.2012] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Inhibitory synapses display a great diversity through varying combinations of presynaptic GABA and glycine release and postsynaptic expression of GABA and glycine receptor subtypes. We hypothesized that increased flexibility offered by this dual transmitter system might serve to tune the inhibitory phenotype to the properties of afferent excitatory synaptic inputs in individual cells. Vestibulocerebellar unipolar brush cells (UBC) receive a single glutamatergic synapse from a mossy fiber (MF), which makes them an ideal model to study excitatory-inhibitory interactions. We examined the functional phenotypes of mixed inhibitory synapses formed by Golgi interneurons onto UBCs in rat slices. We show that glycinergic IPSCs are present in all cells. An additional GABAergic component of large amplitude is only detected in a subpopulation of UBCs. This GABAergic phenotype is strictly anti-correlated with the expression of type II, but not type I, metabotropic glutamate receptors (mGluRs) at the MF synapse. Immunohistochemical stainings and agonist applications show that global UBC expression of glycine and GABA(A) receptors matches the pharmacological profile of IPSCs. Paired recordings of Golgi cells and UBCs confirm the postsynaptic origin of the inhibitory phenotype, including the slow kinetics of glycinergic components. These results strongly suggest the presence of a functional coregulation of excitatory and inhibitory phenotypes at the single-cell level. We propose that slow glycinergic IPSCs may provide an inhibitory tone, setting the gain of the MF to UBC relay, whereas large and fast GABAergic IPSCs may in addition control spike timing in mGluRII-negative UBCs.
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Leto K, Rolando C, Rossi F. The genesis of cerebellar GABAergic neurons: fate potential and specification mechanisms. Front Neuroanat 2012; 6:6. [PMID: 22363268 PMCID: PMC3282257 DOI: 10.3389/fnana.2012.00006] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Accepted: 02/03/2012] [Indexed: 11/15/2022] Open
Abstract
All cerebellar neurons derive from progenitors that proliferate in two germinal neuroepithelia: the ventricular zone (VZ) generates GABAergic neurons, whereas the rhombic lip is the origin of glutamatergic types. Among VZ-derivatives, GABAergic projection neurons, and interneurons are generated according to distinct strategies. Projection neurons (Purkinje cells and nucleo-olivary neurons) are produced at the onset of cerebellar neurogenesis by discrete progenitor pools located in distinct VZ microdomains. These cells are specified within the VZ and acquire mature phenotypes according to cell-autonomous developmental programs. On the other hand, the different categories of inhibitory interneurons derive from a single population of Pax-2-positive precursors that delaminate into the prospective white matter (PWM), where they continue to divide up to postnatal development. Heterotopic/heterochronic transplantation experiments indicate that interneuron progenitors maintain full developmental potentialities up to the end of cerebellar development and acquire mature phenotypes under the influence of environmental cues present in the PWM. Furthermore, the final fate choice occurs in postmitotic cells, rather than dividing progenitors. Extracerebellar cells grafted to the prospective cerebellar white matter are not responsive to local neurogenic cues and fail to adopt clear cerebellar identities. Conversely, cerebellar cells grafted to extracerebellar regions retain typical phenotypes of cerebellar GABAergic interneurons, but acquire type-specific traits under the influence of local cues. These findings indicate that interneuron progenitors are multipotent and sensitive to spatio-temporally patterned environmental signals that regulate the genesis of different categories of interneurons, in precise quantities and at defined times and places.
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Affiliation(s)
- Ketty Leto
- Department of Neuroscience, Neuroscience Institute of Turin, University of Turin Turin, Italy
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Expression of doublecortin, a neuronal migration protein, in unipolar brush cells of the vestibulocerebellum and dorsal cochlear nucleus of the adult rat. Neuroscience 2011; 202:169-83. [PMID: 22198017 DOI: 10.1016/j.neuroscience.2011.12.013] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Revised: 12/11/2011] [Accepted: 12/12/2011] [Indexed: 11/22/2022]
Abstract
Doublecortin (DCX) is a microtubule-associated protein that is critical for neuronal migration and the development of the cerebral cortex. In the adult, it is expressed in newborn neurons in the subventricular and subgranular zones, but not in the mature neurons of the cerebral cortex. By contrast, neurogenesis and neuronal migration of cells in the cerebellum continue into early postnatal life; migration of one class of cerebellar interneuron, unipolar brush cells (UBCs), may continue into adulthood. To explore the possibility of continued neuronal migration in the adult cerebellum, closely spaced sections through the brainstem and cerebellum of adult (3-16 months old) Sprague-Dawley rats were immunolabeled for DCX. Neurons immunoreactive (ir) to DCX were present in the granular cell layer of the vestibulocerebellum, most densely in the transition zone (tz), the region between the flocculus (FL) and ventral paraflocculus (PFL), as well as in the dorsal cochlear nucleus (DCN). These DCX-ir cells had the morphological appearance of UBCs with oval somata and a single dendrite ending in a brush. There were many examples of colocalization of DCX with Eps8 or calretinin, UBC markers. We also identified DCX-ir elements along the fourth ventricle and its lateral recess that had labeled somata but lacked the dendritic structure characteristic of UBCs. Labeled UBCs were seen in nearby white matter. These results suggest that there may be continued neurogenesis and/or migration of UBCs in the adult. Another possibility is that UBCs maintain DCX expression even after migration and maturation, reflecting a role of DCX in adult neuronal plasticity in addition to a developmental role in migration.
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Secretogranin II and its Derivative Peptide, Manserin, are Differentially Localized in Purkinje Cells and Unipolar Brush Cells in the Rat Cerebellum. Int J Pept Res Ther 2011. [DOI: 10.1007/s10989-011-9257-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Baizer JS, Sherwood CC, Hof PR, Witelson SF, Sultan F. Neurochemical and Structural Organization of the Principal Nucleus of the Inferior Olive in the Human. Anat Rec (Hoboken) 2011; 294:1198-216. [DOI: 10.1002/ar.21400] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2011] [Revised: 03/28/2011] [Accepted: 03/28/2011] [Indexed: 02/06/2023]
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Chung SH, Marzban H, Aldinger K, Dixit R, Millen K, Schuurmans C, Hawkes R. Zac1 plays a key role in the development of specific neuronal subsets in the mouse cerebellum. Neural Dev 2011. [PMID: 21592321 DOI: 10.1186/1749‐8104‐6‐25] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023] Open
Abstract
BACKGROUND The cerebellum is composed of a diverse array of neuronal subtypes. Here we have used a candidate approach to identify Zac1, a tumor suppressor gene encoding a zinc finger transcription factor, as a new player in the transcriptional network required for the development of a specific subset of cerebellar nuclei and a population of Golgi cells in the cerebellar cortex. RESULTS We found that Zac1 has a complex expression profile in the developing cerebellum, including in two proliferating progenitor populations; the cerebellar ventricular zone and the external granular layer overlying posterior cerebellar lobules IX and X. Zac1 is also expressed in some postmitotic cerebellar neurons, including a subset of GABAergic interneurons in the medial cerebellar nuclei. Notably, GABAergic interneurons in the cerebellar nuclei are derived from the cerebellar ventricular zone, where Zac1 is also expressed, consistent with a lineage relationship between these two Zac1+ populations. Zac1 is also expressed in a small subset of cells in the posterior vermis, including some neurogranin-immunoreactive (NG+) Golgi cells, which, based on short-term birthdating, are derived from the EGL, where Zac1 is also expressed. However, Zac1+ cells and NG+ Golgi cells in the cerebellar cortex also display unique properties, as they are generated within different, albeit overlapping, time windows. Finally, consistent with the expression profile of Zac1, two conspicuous abnormalities were found in the cerebellum of Zac1 null mice: the medial cerebellar nuclei, and not the others, were significantly reduced in size; and the number of Golgi cells in cerebellar lobule IX was reduced by approximately 60% compared to wild-type littermates. CONCLUSIONS The data presented here indicate that the tumor suppressor gene Zac1 is expressed in a complex fashion in the developing cerebellum, including in two dividing progenitor populations and in specific subsets of postmitotic neurons, including Golgi cells and GABAergic neurons in the medial nuclei, which require Zac1 for their differentiation. We thus conclude that Zac1 is a critical regulator of normal cerebellar development, adding a new transcriptional regulator to the growing list of factors involved in generating neuronal diversity in the developing cerebellum.
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Affiliation(s)
- Seung-Hyuk Chung
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, Faculty of Medicine, University of Calgary, Calgary, Alberta T2N 4N1, Canada.
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Chung SH, Marzban H, Aldinger K, Dixit R, Millen K, Schuurmans C, Hawkes R. Zac1 plays a key role in the development of specific neuronal subsets in the mouse cerebellum. Neural Dev 2011; 6:25. [PMID: 21592321 PMCID: PMC3113315 DOI: 10.1186/1749-8104-6-25] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2011] [Accepted: 05/18/2011] [Indexed: 11/20/2022] Open
Abstract
Background The cerebellum is composed of a diverse array of neuronal subtypes. Here we have used a candidate approach to identify Zac1, a tumor suppressor gene encoding a zinc finger transcription factor, as a new player in the transcriptional network required for the development of a specific subset of cerebellar nuclei and a population of Golgi cells in the cerebellar cortex. Results We found that Zac1 has a complex expression profile in the developing cerebellum, including in two proliferating progenitor populations; the cerebellar ventricular zone and the external granular layer overlying posterior cerebellar lobules IX and X. Zac1 is also expressed in some postmitotic cerebellar neurons, including a subset of GABAergic interneurons in the medial cerebellar nuclei. Notably, GABAergic interneurons in the cerebellar nuclei are derived from the cerebellar ventricular zone, where Zac1 is also expressed, consistent with a lineage relationship between these two Zac1+ populations. Zac1 is also expressed in a small subset of cells in the posterior vermis, including some neurogranin-immunoreactive (NG+) Golgi cells, which, based on short-term birthdating, are derived from the EGL, where Zac1 is also expressed. However, Zac1+ cells and NG+ Golgi cells in the cerebellar cortex also display unique properties, as they are generated within different, albeit overlapping, time windows. Finally, consistent with the expression profile of Zac1, two conspicuous abnormalities were found in the cerebellum of Zac1 null mice: the medial cerebellar nuclei, and not the others, were significantly reduced in size; and the number of Golgi cells in cerebellar lobule IX was reduced by approximately 60% compared to wild-type littermates. Conclusions The data presented here indicate that the tumor suppressor gene Zac1 is expressed in a complex fashion in the developing cerebellum, including in two dividing progenitor populations and in specific subsets of postmitotic neurons, including Golgi cells and GABAergic neurons in the medial nuclei, which require Zac1 for their differentiation. We thus conclude that Zac1 is a critical regulator of normal cerebellar development, adding a new transcriptional regulator to the growing list of factors involved in generating neuronal diversity in the developing cerebellum.
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Affiliation(s)
- Seung-Hyuk Chung
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, Faculty of Medicine, University of Calgary, Calgary, Alberta T2N 4N1, Canada.
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Mugnaini E, Sekerková G, Martina M. The unipolar brush cell: a remarkable neuron finally receiving deserved attention. BRAIN RESEARCH REVIEWS 2011; 66:220-45. [PMID: 20937306 PMCID: PMC3030675 DOI: 10.1016/j.brainresrev.2010.10.001] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2010] [Revised: 10/05/2010] [Accepted: 10/05/2010] [Indexed: 12/17/2022]
Abstract
Unipolar brush cells (UBC) are small, glutamatergic neurons residing in the granular layer of the cerebellar cortex and the granule cell domain of the cochlear nuclear complex. Recent studies indicate that this neuronal class consists of three or more subsets characterized by distinct chemical phenotypes, as well as by intrinsic properties that may shape their synaptic responses and firing patterns. Yet, all UBCs have a unique morphology, as both the dendritic brush and the large endings of the axonal branches participate in the formation of glomeruli. Although UBCs and granule cells may share the same excitatory and inhibitory inputs, the two cell types are distinctively differentiated. Typically, whereas the granule cell has 4-5 dendrites that are innervated by different mossy fibers, and an axon that divides only once to form parallel fibers after ascending to the molecular layer, the UBC has but one short dendrite whose brush engages in synaptic contact with a single mossy fiber terminal, and an axon that branches locally in the granular layer; branches of UBC axons form a non-canonical, cortex-intrinsic category of mossy fibers synapsing with granule cells and other UBCs. This is thought to generate a feed-forward amplification of single mossy fiber afferent signals that would reach the overlying Purkinje cells via ascending granule cell axons and their parallel fibers. In sharp contrast to other classes of cerebellar neurons, UBCs are not distributed homogeneously across cerebellar lobules, and subsets of UBCs also show different, albeit overlapping, distributions. UBCs are conspicuously rare in the expansive lateral cerebellar areas targeted by the cortico-ponto-cerebellar pathway, while they are a constant component of the vermis and the flocculonodular lobe. The presence of UBCs in cerebellar regions involved in the sensorimotor processes that regulate body, head and eye position, as well as in regions of the cochlear nucleus that process sensorimotor information suggests a key role in these critical functions; it also invites further efforts to clarify the cellular biology of the UBCs and their specific functions in the neuronal microcircuits in which they are embedded. High density of UBCs in specific regions of the cerebellar cortex is a feature largely conserved across mammals and suggests an involvement of these neurons in fundamental aspects of the input/output organization as well as in clinical manifestation of focal cerebellar disease.
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Affiliation(s)
- Enrico Mugnaini
- Department of Cellular and Molecular Biology, The Feinberg School of Medicine of Northwestern University, Chicago, IL, USA.
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Sotelo C. Camillo Golgi and Santiago Ramon y Cajal: The anatomical organization of the cortex of the cerebellum. Can the neuron doctrine still support our actual knowledge on the cerebellar structural arrangement? ACTA ACUST UNITED AC 2011; 66:16-34. [DOI: 10.1016/j.brainresrev.2010.05.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2010] [Accepted: 05/19/2010] [Indexed: 10/19/2022]
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Ethanol and Vestibular Stimulation Reveal Simple and Complex Aspects of Cerebellar Heterogeneity. THE CEREBELLUM 2010; 10:475-83. [DOI: 10.1007/s12311-010-0238-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Chung SH, Kim CT, Jeong YG, Lee NS. TBR2-immunopsitive unipolar brush cells are associated with ectopic zebrin II-immunoreactive Purkinje cell clusters in the cerebellum of scrambler mice. Anat Cell Biol 2010; 43:72-7. [PMID: 21190007 PMCID: PMC2998775 DOI: 10.5115/acb.2010.43.1.72] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2010] [Revised: 03/02/2010] [Accepted: 03/03/2010] [Indexed: 11/27/2022] Open
Abstract
Unipolar brush cells (UBCs) are excitatory interneurons with their somata located in the granular layer. Recently, T-brain factor 2 (Tbr2) was shown to be expressed in a subset of UBCs in mouse cerebellum. Scrambler mice exhibit severe cerebellum abnormalities, including the failure of embryonic Purkinje cell dispersal and a complete absence of foliation due to a mutation in the disabled-1 adaptor protein. Since most UBC markers are expressed postnatally, it has proven difficult to identify the relationship between developing Purkinje cell clusters and migrating UBCs. Because scrambler mice closely mimic normal embryonic day 18 cerebellum, we examined whether Tbr2-positive UBCs are associated with Purkinje cell cluster markers such as zebrin II, which is the most studied compartmentation marker in the cerebellum. We investigated the distribution of Tbr2-positive UBCs in this mutant by using anti-Tbr2 immunocytochemistry. The data revealed that Tbr2 immunoreactivity was exclusively present in the nucleus of UBCs in scrambler cerebellum. Based on expression data, a Tbr2-positive UBC map was constructed. In addition, Tbr2-positive UBCs are found associated with ectopic zebrin II-immunoreactive Purkinje cell clusters in scrambler cerebellum. These data suggest that UBCs use Purkinje cell compartmentation to migrate into their final position through interactions with the embryonic array of specific Purkinje cell subtypes.
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Affiliation(s)
- Seung-Hyuk Chung
- Department of Cell Biology and Human Anatomy, School of Medicine, University of California, Davis, Sacramento, California 95817, USA
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Dougherty JD, Schmidt EF, Nakajima M, Heintz N. Analytical approaches to RNA profiling data for the identification of genes enriched in specific cells. Nucleic Acids Res 2010; 38:4218-30. [PMID: 20308160 PMCID: PMC2910036 DOI: 10.1093/nar/gkq130] [Citation(s) in RCA: 217] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
We have recently developed a novel method for the affinity purification of the complete suite of translating mRNA from genetically labeled cell populations. This method permits comprehensive quantitative comparisons of the genes employed by each specific cell type. We provide a detailed description of tools for analysis of data generated with this and related methodologies. An essential question that arises from these data is how to identify those genes that are enriched in each cell type relative to all others. Genes relatively specifically employed by a cell type may contribute to the unique functions of that cell, and thus may become useful targets for development of pharmacological tools for cell-specific manipulations. We describe here a novel statistic, the specificity index, which can be used for comparative quantitative analysis to identify genes enriched in specific cell populations across a large number of profiles. This measure correctly predicts in situ hybridization patterns for many cell types. We apply this measure to a large survey of CNS cell-specific microarray data to identify those genes that are significantly enriched in each population Data and algorithms are available online (www.bactrap.org).
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Affiliation(s)
| | | | | | - Nathaniel Heintz
- *To whom correspondence should be addressed. Tel: 212-327-7955; Fax:212-327-7878;
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Armstrong CL, Chung SH, Armstrong JN, Hochgeschwender U, Jeong YG, Hawkes R. A novel somatostatin-immunoreactive mossy fiber pathway associated with HSP25-immunoreactive purkinje cell stripes in the mouse cerebellum. J Comp Neurol 2009; 517:524-38. [PMID: 19795496 DOI: 10.1002/cne.22167] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Somatostatin 28 immunoreactivity (Sst28-ir) identifies a specific subset of mossy fiber terminals in the adult mouse cerebellum. By using double-labeling immunohistochemistry, we determined that Sst28-ir is associated with presynaptic mossy fiber terminal rosettes, and not Purkinje cells, Golgi cells, or unipolar brush cells. Sst28-ir mossy fibers are restricted to the central zone (lobules VI/VII) and nodular zone (lobules IX, X) of the vermis, and the paraflocculus and flocculus. Within each transverse zone the mossy fiber terminal fields form a reproducible array of parasagittal stripes. The boundaries of Sst28-ir stripes align with a specific array of Purkinje cell stripes revealed by using immunocytochemistry for the small heat shock protein HSP25. In the cerebellum of the homozygous weaver mouse, in which a subpopulation of HSP25-ir Purkinje cells are located ectopically, the corresponding Sst28-ir mossy fiber projection is also ectopic, suggesting a role for a specific Purkinje cell subset in afferent pattern formation. Likewise, in the scrambler mutant mouse, Sst28-ir mossy fibers show a very close association with HSP25-ir Purkinje cell clusters. HSP25 itself does not appear to be critical for normal patterning, however: in the KJR mouse, which does not express cerebellar HSP25, Sst28 expression appears to be normal. Likewise, the Purkinje cell patterning antigens zebrin II and HSP25 are expressed normally in both Sst- and Sst-receptor knockout mice, suggesting that somatostatinergic transmission is not necessary for Purkinje cell stripe formation.
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Affiliation(s)
- C L Armstrong
- Department of Biomedical Science, Ontario Veterinary College, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
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Chung SH, Sillitoe R, Croci L, Badaloni A, Consalez G, Hawkes R. Purkinje cell phenotype restricts the distribution of unipolar brush cells. Neuroscience 2009; 164:1496-508. [DOI: 10.1016/j.neuroscience.2009.09.080] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2009] [Revised: 09/18/2009] [Accepted: 09/28/2009] [Indexed: 10/20/2022]
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Phospholipase Cbeta4 expression identifies a novel subset of unipolar brush cells in the adult mouse cerebellum. THE CEREBELLUM 2009; 8:267-76. [PMID: 19165551 DOI: 10.1007/s12311-009-0092-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Unipolar brush cells (UBCs) are glutamatergic cerebellar interneurons of the granular layer. Previous studies have shown that there are two distinct subsets of UBCs present in the mice cerebellar cortex: calcium-binding protein calretinin (CR) positive and metabotropic glutamate receptor (mGluR)1alpha positive. In this study, we identify phospholipase C (PLC) beta4 as an antigenic marker of a novel subset of UBCs. Double immunolabeling reveals that none of the CR+ subset expresses PLCbeta4. In contrast, most members of the mGluR1alpha subset also express PLCbeta4. In addition, 65% of the PLCbeta4+ subset does not express mGluR1alpha. Thus, there are three distinct UBC subsets in the mouse cerebellum: CR+/PLCbeta4-/mGluR1alpha-, PLCbeta4+/mGluR1alpha-/CR-, and mGluR1alpha+/PLCbeta4+/CR-. Each has a different topographical distribution, both between lobules and mediolaterally within the vermis. The development of PLCbeta4 expression in UBCs is exclusively postnatal--first seen only at P12 and mature at about 3 weeks. A distinct subset of PLCbeta4+ UBCs is also present in primary cerebellar cultures.
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The functional equivalence of ascending and parallel fiber inputs in cerebellar computation. J Neurosci 2009; 29:8462-73. [PMID: 19571137 DOI: 10.1523/jneurosci.5718-08.2009] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
At the center of the computational cerebellar circuitry are Purkinje cells, which integrate synaptic inputs from >150,000 granule cell inputs. Traditional theories of cerebellar function assume that all granule cell inputs are comparable. However, it has recently been suggested that the two anatomically distinct granule cell inputs, ascending and parallel fiber, have different functional roles. By systematically examining the efficacy of patches of granule cells with photostimulation, we found no differences in the efficacy of the two inputs in driving the activity of, or in producing postsynaptic currents in, Purkinje cells in cerebellar slices in vitro. We also found that the activity of Purkinje cells was significantly increased upon stimulation of lateral granule cells in vivo. Moreover, when we estimated parallel fiber and ascending apparent unitary EPSC amplitudes using photostimulation in cerebellar slices in vitro, we found them to be indistinguishable. These results are inconsistent with differential functional roles for these two inputs. Instead, our data support theories of cerebellar computation that consider granule cell inputs to be functionally comparable.
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