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Asemi-Rad A, Ghiyamihoor F, Consalez GG, Marzban H. Ablation of Projection Glutamatergic Neurons in the Lateral Cerebellar Nuclei Alters Motor Coordination in Vglut2-Cre+ Mice. CEREBELLUM (LONDON, ENGLAND) 2024; 23:1313-1320. [PMID: 37289359 DOI: 10.1007/s12311-023-01575-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 06/01/2023] [Indexed: 06/09/2023]
Abstract
Cerebellar nuclei (CN) constitute the sole cerebellar output to the rest of the central nervous system and play a central role in cerebellar circuits. Accumulating evidence from both human genetics and animal studies point to a crucial role for CN connectivity in neurological diseases, including several types of ataxia. However, because of the compact and restricted topography and close functional connection between the CN and the cerebellar cortex, identifying cerebellar deficits exclusively linked to CN is challenging. In this study, we have experimentally ablated large projection glutamatergic neurons of the lateral CN and evaluated the impact of this selective manipulation on motor coordination in mice. To this end, through stereotaxic surgery, we injected the lateral CN of Vglut2-Cre+ mice with an adeno-associated virus (AAV) encoding a Cre-dependent diphtheria toxin receptor (DTR), followed by an intraperitoneal injection of diphtheria toxin (DT) to ablate the glutamatergic neurons of the lateral nucleus. Double immunostaining of cerebellar sections with anti-SMI32 and -GFP antibodies revealed GFP expression and provided evidence of SMI32+ neuron degeneration at the site of AAV injection in the lateral nucleus of Vglut2-Cre+ mice. No changes were observed in Vglut2-Cre negative mice. Analysis of motor coordination by rotarod test indicated that the latency to fall was significantly different before and after AAV/DT injection in the Vglut2-Cre+ group. Elapsed time and number of steps in the beam walking test were significantly higher in AAV/DT injected Vglut2-Cre+ AAV/DT mice compared to controls. We demonstrate for the first time that partial degeneration of glutamatergic neurons in the lateral CN is sufficient to induce an ataxic phenotype.
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Affiliation(s)
- Azam Asemi-Rad
- Department of Human Anatomy and Cell Science, Max Rady College of Medicine, Rady Faculty of Health science, University of Manitoba, Winnipeg, MB, Canada
- The Children's Hospital Research Institute of Manitoba (CHRIM), Rady Faculty of Health science, University of Manitoba, Winnipeg, MB, Canada
| | - Farshid Ghiyamihoor
- Department of Human Anatomy and Cell Science, Max Rady College of Medicine, Rady Faculty of Health science, University of Manitoba, Winnipeg, MB, Canada
- The Children's Hospital Research Institute of Manitoba (CHRIM), Rady Faculty of Health science, University of Manitoba, Winnipeg, MB, Canada
| | - G Giacomo Consalez
- Division of Neuroscience, Vita-Salute San Raffaele University, Milan, Italy
| | - Hassan Marzban
- Department of Human Anatomy and Cell Science, Max Rady College of Medicine, Rady Faculty of Health science, University of Manitoba, Winnipeg, MB, Canada.
- The Children's Hospital Research Institute of Manitoba (CHRIM), Rady Faculty of Health science, University of Manitoba, Winnipeg, MB, Canada.
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2
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Damuth DL, Cunningham DD, Silva EM. Sox21 homeologs autoregulate expression levels to control progression through neurogenesis. Genesis 2024; 62:e23612. [PMID: 39054872 DOI: 10.1002/dvg.23612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 05/29/2024] [Accepted: 06/10/2024] [Indexed: 07/27/2024]
Abstract
The SRY HMG box transcription factor Sox21 plays multiple critical roles in neurogenesis, with its function dependent on concentration and developmental stage. In the allotetraploid Xenopus laevis, there are two homeologs of sox21, namely sox21.S and sox21.L. Previous studies focused on Sox21.S, but its amino acid sequence is divergent, lacking conserved poly-A stretches and bearing more similarity with ancestral homologs. In contrast, Sox21.L shares higher sequence similarity with mouse and chick Sox21. To determine if Sox21.S and Sox21.L have distinct functions, we conducted gain and loss-of-function studies in Xenopus embryos. Our studies revealed that Sox21.S and Sox21.L are functionally redundant, but Sox21.L is more effective at driving changes than Sox21.S. These results also support our earlier findings in ectodermal explants, demonstrating that Sox21 function is dose-dependent. While Sox21 is necessary for primary neuron formation, high levels prevent their formation. Strikingly, these proteins autoregulate, with high levels of Sox21.L reducing sox21.S and sox21.L mRNA levels, and decreased Sox21.S promoting increased expression of sox21.L. Our findings shed light on the intricate concentration-dependent roles of Sox21 homeologs in Xenopus neurogenesis.
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Affiliation(s)
- Dillon L Damuth
- Department of Biology, Georgetown University, Washington, DC, USA
| | | | - Elena M Silva
- Department of Biology, Georgetown University, Washington, DC, USA
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3
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Lee AS, Arefin TM, Gubanova A, Stephen DN, Liu Y, Lao Z, Krishnamurthy A, De Marco García NV, Heck DH, Zhang J, Rajadhyaksha AM, Joyner AL. Cerebellar output neurons impair non-motor behaviors by altering development of extracerebellar connectivity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.08.602496. [PMID: 39026865 PMCID: PMC11257463 DOI: 10.1101/2024.07.08.602496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/20/2024]
Abstract
The capacity of the brain to compensate for insults during development depends on the type of cell loss, whereas the consequences of genetic mutations in the same neurons are difficult to predict. We reveal powerful compensation from outside the cerebellum when the excitatory cerebellar output neurons are ablated embryonically and demonstrate that the minimum requirement for these neurons is for motor coordination and not learning and social behaviors. In contrast, loss of the homeobox transcription factors Engrailed1/2 (EN1/2) in the cerebellar excitatory lineage leads to additional deficits in adult learning and spatial working memory, despite half of the excitatory output neurons being intact. Diffusion MRI indicates increased thalamo-cortico-striatal connectivity in En1/2 mutants, showing that the remaining excitatory neurons lacking En1/2 exert adverse effects on extracerebellar circuits regulating motor learning and select non-motor behaviors. Thus, an absence of cerebellar output neurons is less disruptive than having cerebellar genetic mutations.
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Affiliation(s)
- Andrew S. Lee
- Developmental Biology Program, Sloan Kettering Institute, New York 10065, NY, USA
- Neuroscience Program, Weill Cornell Graduate School of Medical Sciences, New York 10021, NY, USA
| | - Tanzil M. Arefin
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University Grossman School of Medicine, New York 10016, NY, USA
- Present Address: Center for Neurotechnology in Mental Health Research, Department of Biomedical Engineering, The Pennsylvania State University, University Park, PA 16801, USA
| | - Alina Gubanova
- Developmental Biology Program, Sloan Kettering Institute, New York 10065, NY, USA
| | - Daniel N. Stephen
- Developmental Biology Program, Sloan Kettering Institute, New York 10065, NY, USA
| | - Yu Liu
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN 55812, USA
- Center for Cerebellar Network Structure and Function in Health and Disease, University of Minnesota, Duluth, MN 55812, USA
| | - Zhimin Lao
- Developmental Biology Program, Sloan Kettering Institute, New York 10065, NY, USA
| | - Anjana Krishnamurthy
- Developmental Biology Program, Sloan Kettering Institute, New York 10065, NY, USA
- Neuroscience Program, Weill Cornell Graduate School of Medical Sciences, New York 10021, NY, USA
| | - Natalia V. De Marco García
- Neuroscience Program, Weill Cornell Graduate School of Medical Sciences, New York 10021, NY, USA
- Center for Neurogenetics, Brain and Mind Research Institute, Weill Cornell Medicine, New York 10021, NY 10021, USA
| | - Detlef H. Heck
- Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN 55812, USA
- Center for Cerebellar Network Structure and Function in Health and Disease, University of Minnesota, Duluth, MN 55812, USA
| | - Jiangyang Zhang
- Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York University Grossman School of Medicine, New York 10016, NY, USA
| | - Anjali M. Rajadhyaksha
- Neuroscience Program, Weill Cornell Graduate School of Medical Sciences, New York 10021, NY, USA
- Pediatric Neurology, Department of Pediatrics, Weill Cornell Medicine, New York 10021, NY, USA
- Weill Cornell Autism Research Program, Weill Cornell Medicine, New York 10021, NY, USA
- Present address: Center for Substance Abuse Research, Lewis Katz School of Medicine, Temple University, Philadelphia, PA 19140, USA and Department of Neural Sciences, Lewis Katz School of Medicine, Temple University, Philadelphia, PA 19140, USA
| | - Alexandra L. Joyner
- Developmental Biology Program, Sloan Kettering Institute, New York 10065, NY, USA
- Neuroscience Program, Weill Cornell Graduate School of Medical Sciences, New York 10021, NY, USA
- Biochemistry, Cell and Molecular Biology Program, Weill Cornell Graduate School of Medical Sciences, New York 10021, NY, USA
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4
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Kebschull JM, Casoni F, Consalez GG, Goldowitz D, Hawkes R, Ruigrok TJH, Schilling K, Wingate R, Wu J, Yeung J, Uusisaari MY. Cerebellum Lecture: the Cerebellar Nuclei-Core of the Cerebellum. CEREBELLUM (LONDON, ENGLAND) 2024; 23:620-677. [PMID: 36781689 PMCID: PMC10951048 DOI: 10.1007/s12311-022-01506-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 12/10/2022] [Indexed: 02/15/2023]
Abstract
The cerebellum is a key player in many brain functions and a major topic of neuroscience research. However, the cerebellar nuclei (CN), the main output structures of the cerebellum, are often overlooked. This neglect is because research on the cerebellum typically focuses on the cortex and tends to treat the CN as relatively simple output nuclei conveying an inverted signal from the cerebellar cortex to the rest of the brain. In this review, by adopting a nucleocentric perspective we aim to rectify this impression. First, we describe CN anatomy and modularity and comprehensively integrate CN architecture with its highly organized but complex afferent and efferent connectivity. This is followed by a novel classification of the specific neuronal classes the CN comprise and speculate on the implications of CN structure and physiology for our understanding of adult cerebellar function. Based on this thorough review of the adult literature we provide a comprehensive overview of CN embryonic development and, by comparing cerebellar structures in various chordate clades, propose an interpretation of CN evolution. Despite their critical importance in cerebellar function, from a clinical perspective intriguingly few, if any, neurological disorders appear to primarily affect the CN. To highlight this curious anomaly, and encourage future nucleocentric interpretations, we build on our review to provide a brief overview of the various syndromes in which the CN are currently implicated. Finally, we summarize the specific perspectives that a nucleocentric view of the cerebellum brings, move major outstanding issues in CN biology to the limelight, and provide a roadmap to the key questions that need to be answered in order to create a comprehensive integrated model of CN structure, function, development, and evolution.
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Affiliation(s)
- Justus M Kebschull
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, 21205, USA.
| | - Filippo Casoni
- Division of Neuroscience, San Raffaele Scientific Institute, and San Raffaele University, Milan, Italy
| | - G Giacomo Consalez
- Division of Neuroscience, San Raffaele Scientific Institute, and San Raffaele University, Milan, Italy
| | - Daniel Goldowitz
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, Canada
| | - Richard Hawkes
- Department of Cell Biology & Anatomy and Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, T2N 4N1, Canada
| | - Tom J H Ruigrok
- Department of Neuroscience, Erasmus MC, Rotterdam, the Netherlands
| | - Karl Schilling
- Department of Anatomy, Anatomy & Cell Biology, Rheinische Friedrich-Wilhelms-Universität, 53115, Bonn, Federal Republic of Germany
| | - Richard Wingate
- MRC Centre for Neurodevelopmental Disorders, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
| | - Joshua Wu
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, Canada
| | - Joanna Yeung
- Department of Medical Genetics, Centre for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, Canada
| | - Marylka Yoe Uusisaari
- Neuronal Rhythms in Movement Unit, Okinawa Institute of Science and Technology, 1919-1 Tancha, Onna-Son, Kunigami-Gun, Okinawa, 904-0495, Japan.
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5
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Schilling K. Revisiting the development of cerebellar inhibitory interneurons in the light of single-cell genetic analyses. Histochem Cell Biol 2024; 161:5-27. [PMID: 37940705 PMCID: PMC10794478 DOI: 10.1007/s00418-023-02251-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/12/2023] [Indexed: 11/10/2023]
Abstract
The present review aims to provide a short update of our understanding of the inhibitory interneurons of the cerebellum. While these cells constitute but a minority of all cerebellar neurons, their functional significance is increasingly being recognized. For one, inhibitory interneurons of the cerebellar cortex are now known to constitute a clearly more diverse group than their traditional grouping as stellate, basket, and Golgi cells suggests, and this diversity is now substantiated by single-cell genetic data. The past decade or so has also provided important information about interneurons in cerebellar nuclei. Significantly, developmental studies have revealed that the specification and formation of cerebellar inhibitory interneurons fundamentally differ from, say, the cortical interneurons, and define a mode of diversification critically dependent on spatiotemporally patterned external signals. Last, but not least, in the past years, dysfunction of cerebellar inhibitory interneurons could also be linked with clinically defined deficits. I hope that this review, however fragmentary, may stimulate interest and help focus research towards understanding the cerebellum.
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Affiliation(s)
- Karl Schilling
- Anatomisches Institut - Anatomie und Zellbiologie, Rheinische Friedrich-Wilhelms-Universität Bonn, Nussallee 10, 53115, Bonn, Germany.
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6
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Cheung LYM, Menage L, Rizzoti K, Hamilton G, Dumontet T, Basham K, Daly AZ, Brinkmeier ML, Masser BE, Treier M, Cobb J, Delogu A, Lovell-Badge R, Hammer GD, Camper SA. Novel Candidate Regulators and Developmental Trajectory of Pituitary Thyrotropes. Endocrinology 2023; 164:bqad076. [PMID: 37183548 PMCID: PMC10227867 DOI: 10.1210/endocr/bqad076] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 04/27/2023] [Accepted: 05/10/2023] [Indexed: 05/16/2023]
Abstract
The pituitary gland regulates growth, metabolism, reproduction, the stress response, uterine contractions, lactation, and water retention. It secretes hormones in response to hypothalamic input, end organ feedback, and diurnal cues. The mechanisms by which pituitary stem cells are recruited to proliferate, maintain quiescence, or differentiate into specific cell types, especially thyrotropes, are not well understood. We used single-cell RNA sequencing in juvenile P7 mouse pituitary cells to identify novel factors in pituitary cell populations, with a focus on thyrotropes and rare subtypes. We first observed cells coexpressing markers of both thyrotropes and gonadotropes, such as Pou1f1 and Nr5a1. This was validated in vivo by both immunohistochemistry and lineage tracing of thyrotropes derived from Nr5a1-Cre; mTmG mice and demonstrates that Nr5a1-progenitors give rise to a proportion of thyrotropes during development. Our data set also identifies novel factors expressed in pars distalis and pars tuberalis thyrotropes, including the Shox2b isoform in all thyrotropes and Sox14 specifically in Pou1f1-negative pars tuberalis thyrotropes. We have therefore used single-cell transcriptomics to determine a novel developmental trajectory for thyrotropes and potential novel regulators of thyrotrope populations.
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Affiliation(s)
- Leonard Y M Cheung
- Department of Human Genetics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Lucy Menage
- School of Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London SE5 8AF, UK
| | - Karine Rizzoti
- Laboratory of Stem Cell Biology and Developmental Genetics, The Francis Crick Institute, London NW1 1AT, UK
| | - Greg Hamilton
- Department of Biological Sciences, University of Calgary, Calgary AB T2N 1N4, Canada
| | - Typhanie Dumontet
- Training Program in Organogenesis, Center for Cell Plasticity and Organ Design, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Internal Medicine, Division of Metabolism, Endocrinology, and Diabetes, University of Michigan, Ann Arbor, MI 48109, USA
| | - Kaitlin Basham
- Department of Internal Medicine, Division of Metabolism, Endocrinology, and Diabetes, University of Michigan, Ann Arbor, MI 48109, USA
- Current affiliation: Huntsman Cancer Institute, University of Utah, Salt Lake City, UT 84112, USA
| | - Alexandre Z Daly
- Department of Human Genetics, University of Michigan, Ann Arbor, MI 48109, USA
- Current affiliation is Vanguard, Valley Forge, PA 19482, USA
| | | | - Bailey E Masser
- Department of Human Genetics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Mathias Treier
- Max Delbrϋck Center for Molecular Medicine (MDC), 13092 Berlin, Germany
- Charité-Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - John Cobb
- Department of Biological Sciences, University of Calgary, Calgary AB T2N 1N4, Canada
| | - Alessio Delogu
- School of Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London SE5 8AF, UK
| | - Robin Lovell-Badge
- Laboratory of Stem Cell Biology and Developmental Genetics, The Francis Crick Institute, London NW1 1AT, UK
| | - Gary D Hammer
- Department of Internal Medicine, Division of Metabolism, Endocrinology, and Diabetes, University of Michigan, Ann Arbor, MI 48109, USA
- Endocrine Oncology Program, Rogel Cancer Center, University of Michigan, Ann Arbor, MI 48109, USA
| | - Sally A Camper
- Department of Human Genetics, University of Michigan, Ann Arbor, MI 48109, USA
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7
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Khouri-Farah N, Guo Q, Morgan K, Shin J, Li JYH. Integrated single-cell transcriptomic and epigenetic study of cell state transition and lineage commitment in embryonic mouse cerebellum. SCIENCE ADVANCES 2022; 8:eabl9156. [PMID: 35363520 PMCID: PMC10938588 DOI: 10.1126/sciadv.abl9156] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 02/07/2022] [Indexed: 06/14/2023]
Abstract
Recent studies using single-cell RNA-sequencing have revealed cellular heterogeneity in the developing mammalian cerebellum, yet the regulatory logic underlying this cellular diversity remains to be elucidated. Using integrated single-cell RNA and ATAC analyses, we resolved developmental trajectories of cerebellar progenitors and identified putative trans- and cis-elements that control cell state transition. We reverse engineered gene regulatory networks (GRNs) of each cerebellar cell type. Through in silico simulations and in vivo experiments, we validated the efficacy of GRN analyses and uncovered the molecular control of a posterior transitory zone (PTZ), a distinct progenitor zone residing immediately anterior to the morphologically defined rhombic lip (RL). We showed that perturbing cell fate specification in the PTZ and RL causes posterior cerebellar vermis hypoplasia, the most common cerebellar birth defect in humans. Our study provides a foundation for comprehensive studies of developmental programs of the mammalian cerebellum.
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Affiliation(s)
- Nagham Khouri-Farah
- Department of Genetics and Genome Sciences, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT 06030-6403, USA
| | - Qiuxia Guo
- Department of Genetics and Genome Sciences, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT 06030-6403, USA
| | - Kerry Morgan
- Department of Genetics and Genome Sciences, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT 06030-6403, USA
| | - Jihye Shin
- Department of Genetics and Genome Sciences, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT 06030-6403, USA
| | - James Y. H. Li
- Department of Genetics and Genome Sciences, University of Connecticut School of Medicine, 263 Farmington Avenue, Farmington, CT 06030-6403, USA
- Institute for Systems Genomics, University of Connecticut, 400 Farmington Avenue, Farmington, CT 06030-6403, USA
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8
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Kang S, Jun S, Baek SJ, Park H, Yamamoto Y, Tanaka-Yamamoto K. Recent Advances in the Understanding of Specific Efferent Pathways Emerging From the Cerebellum. Front Neuroanat 2021; 15:759948. [PMID: 34975418 PMCID: PMC8716603 DOI: 10.3389/fnana.2021.759948] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 11/15/2021] [Indexed: 11/13/2022] Open
Abstract
The cerebellum has a long history in terms of research on its network structures and motor functions, yet our understanding of them has further advanced in recent years owing to technical developments, such as viral tracers, optogenetic and chemogenetic manipulation, and single cell gene expression analyses. Specifically, it is now widely accepted that the cerebellum is also involved in non-motor functions, such as cognitive and psychological functions, mainly from studies that have clarified neuronal pathways from the cerebellum to other brain regions that are relevant to these functions. The techniques to manipulate specific neuronal pathways were effectively utilized to demonstrate the involvement of the cerebellum and its pathways in specific brain functions, without altering motor activity. In particular, the cerebellar efferent pathways that have recently gained attention are not only monosynaptic connections to other brain regions, including the periaqueductal gray and ventral tegmental area, but also polysynaptic connections to other brain regions, including the non-primary motor cortex and hippocampus. Besides these efferent pathways associated with non-motor functions, recent studies using sophisticated experimental techniques further characterized the historically studied efferent pathways that are primarily associated with motor functions. Nevertheless, to our knowledge, there are no articles that comprehensively describe various cerebellar efferent pathways, although there are many interesting review articles focusing on specific functions or pathways. Here, we summarize the recent findings on neuronal networks projecting from the cerebellum to several brain regions. We also introduce various techniques that have enabled us to advance our understanding of the cerebellar efferent pathways, and further discuss possible directions for future research regarding these efferent pathways and their functions.
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Affiliation(s)
- Seulgi Kang
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, South Korea
- Division of Bio-Medical Science and Technology, KIST School, University of Science and Technology (UST), Seoul, South Korea
| | - Soyoung Jun
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, South Korea
- Division of Bio-Medical Science and Technology, KIST School, University of Science and Technology (UST), Seoul, South Korea
| | - Soo Ji Baek
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, South Korea
- Division of Bio-Medical Science and Technology, KIST School, University of Science and Technology (UST), Seoul, South Korea
| | - Heeyoun Park
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, South Korea
| | - Yukio Yamamoto
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, South Korea
| | - Keiko Tanaka-Yamamoto
- Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul, South Korea
- Division of Bio-Medical Science and Technology, KIST School, University of Science and Technology (UST), Seoul, South Korea
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9
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Judd EN, Lewis SM, Person AL. Diverse inhibitory projections from the cerebellar interposed nucleus. eLife 2021; 10:e66231. [PMID: 34542410 PMCID: PMC8483738 DOI: 10.7554/elife.66231] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 09/19/2021] [Indexed: 11/17/2022] Open
Abstract
The cerebellum consists of parallel circuit modules that contribute to diverse behaviors, spanning motor to cognitive. Recent work employing cell-type-specific tracing has identified circumscribed output channels of the cerebellar nuclei (CbN) that could confer tight functional specificity. These studies have largely focused on excitatory projections of the CbN, however, leaving open the question of whether inhibitory neurons also constitute multiple output modules. We mapped output and input patterns to intersectionally restricted cell types of the interposed and adjacent interstitial nuclei in mice. In contrast to the widespread assumption of primarily excitatory outputs and restricted inferior olive-targeting inhibitory output, we found that inhibitory neurons from this region ramified widely within the brainstem, targeting both motor- and sensory-related nuclei, distinct from excitatory output targets. Despite differences in output targeting, monosynaptic rabies tracing revealed largely shared afferents to both cell classes. We discuss the potential novel functional roles for inhibitory outputs in the context of cerebellar theory.
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Affiliation(s)
- Elena N Judd
- Department of Physiology and Biophysics, University of Colorado School of Medicine, Anschutz Medical CampusAuroraUnited States
| | - Samantha M Lewis
- Department of Physiology and Biophysics, University of Colorado School of Medicine, Anschutz Medical CampusAuroraUnited States
| | - Abigail L Person
- Department of Physiology and Biophysics, University of Colorado School of Medicine, Anschutz Medical CampusAuroraUnited States
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10
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Sarropoulos I, Sepp M, Frömel R, Leiss K, Trost N, Leushkin E, Okonechnikov K, Joshi P, Giere P, Kutscher LM, Cardoso-Moreira M, Pfister SM, Kaessmann H. Developmental and evolutionary dynamics of cis-regulatory elements in mouse cerebellar cells. Science 2021; 373:eabg4696. [PMID: 34446581 PMCID: PMC7611596 DOI: 10.1126/science.abg4696] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 07/14/2021] [Indexed: 12/13/2022]
Abstract
Organ development is orchestrated by cell- and time-specific gene regulatory networks. In this study, we investigated the regulatory basis of mouse cerebellum development from early neurogenesis to adulthood. By acquiring snATAC-seq (single-nucleus assay for transposase accessible chromatin using sequencing) profiles for ~90,000 cells spanning 11 stages, we mapped cerebellar cell types and identified candidate cis-regulatory elements (CREs). We detected extensive spatiotemporal heterogeneity among progenitor cells and a gradual divergence in the regulatory programs of cerebellar neurons during differentiation. Comparisons to vertebrate genomes and snATAC-seq profiles for ∼20,000 cerebellar cells from the marsupial opossum revealed a shared decrease in CRE conservation during development and differentiation as well as differences in constraint between cell types. Our work delineates the developmental and evolutionary dynamics of gene regulation in cerebellar cells and provides insights into mammalian organ development.
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Affiliation(s)
- Ioannis Sarropoulos
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, D-69120 Heidelberg, Germany.
| | - Mari Sepp
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, D-69120 Heidelberg, Germany.
| | - Robert Frömel
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, D-69120 Heidelberg, Germany
| | - Kevin Leiss
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, D-69120 Heidelberg, Germany
| | - Nils Trost
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, D-69120 Heidelberg, Germany
| | - Evgeny Leushkin
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, D-69120 Heidelberg, Germany
| | - Konstantin Okonechnikov
- Hopp Children's Cancer Center (KiTZ) Heidelberg, Division of Pediatric Neurooncology, German Cancer Consortium (DKTK), and German Cancer Research Center (DKFZ), D-69120 Heidelberg, Germany
| | - Piyush Joshi
- Hopp Children's Cancer Center (KiTZ) Heidelberg, Division of Pediatric Neurooncology, German Cancer Consortium (DKTK), and German Cancer Research Center (DKFZ), D-69120 Heidelberg, Germany
| | - Peter Giere
- Museum für Naturkunde, Leibniz Institute for Evolution and Biodiversity Science, Berlin, Germany
| | - Lena M Kutscher
- Hopp Children's Cancer Center (KiTZ) Heidelberg, Developmental Origins of Pediatric Cancer Group, German Cancer Research Center (DKFZ), D-69120 Heidelberg, Germany
| | - Margarida Cardoso-Moreira
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, D-69120 Heidelberg, Germany
- Evolutionary Developmental Biology Laboratory, Francis Crick Institute, London NW1 1AT, UK
| | - Stefan M Pfister
- Hopp Children's Cancer Center (KiTZ) Heidelberg, Division of Pediatric Neurooncology, German Cancer Consortium (DKTK), and German Cancer Research Center (DKFZ), D-69120 Heidelberg, Germany.
- Department of Pediatric Hematology and Oncology, Heidelberg University Hospital, Heidelberg, Germany
| | - Henrik Kaessmann
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, D-69120 Heidelberg, Germany.
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11
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Transcriptome programs involved in the development and structure of the cerebellum. Cell Mol Life Sci 2021; 78:6431-6451. [PMID: 34406416 PMCID: PMC8558292 DOI: 10.1007/s00018-021-03911-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Accepted: 08/02/2021] [Indexed: 12/23/2022]
Abstract
In the past two decades, mounting evidence has modified the classical view of the cerebellum as a brain region specifically involved in the modulation of motor functions. Indeed, clinical studies and engineered mouse models have highlighted cerebellar circuits implicated in cognitive functions and behavior. Furthermore, it is now clear that insults occurring in specific time windows of cerebellar development can affect cognitive performance later in life and are associated with neurological syndromes, such as Autism Spectrum Disorder. Despite its almost homogenous cytoarchitecture, how cerebellar circuits form and function is not completely elucidated yet. Notably, the apparently simple neuronal organization of the cerebellum, in which Purkinje cells represent the only output, hides an elevated functional diversity even within the same neuronal population. Such complexity is the result of the integration of intrinsic morphogenetic programs and extracellular cues from the surrounding environment, which impact on the regulation of the transcriptome of cerebellar neurons. In this review, we briefly summarize key features of the development and structure of the cerebellum before focusing on the pathways involved in the acquisition of the cerebellar neuron identity. We focus on gene expression and mRNA processing programs, including mRNA methylation, trafficking and splicing, that are set in motion during cerebellar development and participate to its physiology. These programs are likely to add new layers of complexity and versatility that are fundamental for the adaptability of cerebellar neurons.
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12
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Jager P, Moore G, Calpin P, Durmishi X, Salgarella I, Menage L, Kita Y, Wang Y, Kim DW, Blackshaw S, Schultz SR, Brickley S, Shimogori T, Delogu A. Dual midbrain and forebrain origins of thalamic inhibitory interneurons. eLife 2021; 10:e59272. [PMID: 33522480 PMCID: PMC7906600 DOI: 10.7554/elife.59272] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Accepted: 01/31/2021] [Indexed: 12/12/2022] Open
Abstract
The ubiquitous presence of inhibitory interneurons in the thalamus of primates contrasts with the sparsity of interneurons reported in mice. Here, we identify a larger than expected complexity and distribution of interneurons across the mouse thalamus, where all thalamic interneurons can be traced back to two developmental programmes: one specified in the midbrain and the other in the forebrain. Interneurons migrate to functionally distinct thalamocortical nuclei depending on their origin: the abundant, midbrain-derived class populates the first and higher order sensory thalamus while the rarer, forebrain-generated class is restricted to some higher order associative regions. We also observe that markers for the midbrain-born class are abundantly expressed throughout the thalamus of the New World monkey marmoset. These data therefore reveal that, despite the broad variability in interneuron density across mammalian species, the blueprint of the ontogenetic organisation of thalamic interneurons of larger-brained mammals exists and can be studied in mice.
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Affiliation(s)
- Polona Jager
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King’s College LondonLondonUnited Kingdom
| | - Gerald Moore
- Department of Bioengineering, Imperial College LondonLondonUnited Kingdom
- Department of Life Sciences and Centre for Neurotechnology, Imperial College LondonLondonUnited Kingdom
| | - Padraic Calpin
- Department of Physics and Astronomy, University College LondonLondonUnited Kingdom
| | - Xhuljana Durmishi
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King’s College LondonLondonUnited Kingdom
| | - Irene Salgarella
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King’s College LondonLondonUnited Kingdom
| | - Lucy Menage
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King’s College LondonLondonUnited Kingdom
| | | | - Yan Wang
- RIKEN, Center for Brain Science (CBS)SaitamaJapan
| | - Dong Won Kim
- The Solomon H. Snyder Department of Neuroscience, School of Medicine, Johns Hopkins UniversityBaltimoreUnited States
| | - Seth Blackshaw
- The Solomon H. Snyder Department of Neuroscience, School of Medicine, Johns Hopkins UniversityBaltimoreUnited States
| | - Simon R Schultz
- Department of Bioengineering, Imperial College LondonLondonUnited Kingdom
| | - Stephen Brickley
- Department of Life Sciences and Centre for Neurotechnology, Imperial College LondonLondonUnited Kingdom
| | | | - Alessio Delogu
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King’s College LondonLondonUnited Kingdom
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13
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Kebschull JM, Richman EB, Ringach N, Friedmann D, Albarran E, Kolluru SS, Jones RC, Allen WE, Wang Y, Cho SW, Zhou H, Ding JB, Chang HY, Deisseroth K, Quake SR, Luo L. Cerebellar nuclei evolved by repeatedly duplicating a conserved cell-type set. Science 2020; 370:eabd5059. [PMID: 33335034 PMCID: PMC8510508 DOI: 10.1126/science.abd5059] [Citation(s) in RCA: 98] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 10/26/2020] [Indexed: 11/02/2022]
Abstract
How have complex brains evolved from simple circuits? Here we investigated brain region evolution at cell-type resolution in the cerebellar nuclei, the output structures of the cerebellum. Using single-nucleus RNA sequencing in mice, chickens, and humans, as well as STARmap spatial transcriptomic analysis and whole-central nervous system projection tracing, we identified a conserved cell-type set containing two region-specific excitatory neuron classes and three region-invariant inhibitory neuron classes. This set constitutes an archetypal cerebellar nucleus that was repeatedly duplicated to form new regions. The excitatory cell class that preferentially funnels information to lateral frontal cortices in mice becomes predominant in the massively expanded human lateral nucleus. Our data suggest a model of brain region evolution by duplication and divergence of entire cell-type sets.
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Affiliation(s)
| | - Ethan B Richman
- Department of Biology, Stanford University, Stanford, CA 94305, USA
- Neurosciences Program, Stanford University, Stanford, CA 94305, USA
- Department of Bioengineering, Stanford University, Stanford, CA 94305, USA
| | - Noam Ringach
- Department of Biology, Stanford University, Stanford, CA 94305, USA
| | - Drew Friedmann
- Department of Biology, Stanford University, Stanford, CA 94305, USA
| | - Eddy Albarran
- Neurosciences Program, Stanford University, Stanford, CA 94305, USA
| | - Sai Saroja Kolluru
- Department of Bioengineering, Stanford University, Stanford, CA 94305, USA
- Department of Applied Physics, Stanford University, Stanford, CA 94305, USA
- Chan Zuckerberg Biohub, Stanford, CA 94305, USA
| | - Robert C Jones
- Department of Bioengineering, Stanford University, Stanford, CA 94305, USA
- Department of Applied Physics, Stanford University, Stanford, CA 94305, USA
| | - William E Allen
- Department of Biology, Stanford University, Stanford, CA 94305, USA
- Neurosciences Program, Stanford University, Stanford, CA 94305, USA
- Department of Bioengineering, Stanford University, Stanford, CA 94305, USA
- Society of Fellows, Harvard University, Cambridge, MA 02138, USA
| | - Ying Wang
- Department of Animal Science, University of California, Davis, CA 95616, USA
| | - Seung Woo Cho
- Center for Personal Dynamic Regulomes, Stanford University, Stanford, CA 94305, USA
| | - Huaijun Zhou
- Department of Animal Science, University of California, Davis, CA 95616, USA
| | - Jun B Ding
- Department of Neurosurgery, Stanford University, Stanford, CA 94305, USA
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, 94305, USA
| | - Howard Y Chang
- Center for Personal Dynamic Regulomes, Stanford University, Stanford, CA 94305, USA
- Howard Hughes Medical Institute, Stanford University, Stanford, CA 94305, USA
| | - Karl Deisseroth
- Department of Bioengineering, Stanford University, Stanford, CA 94305, USA
- Howard Hughes Medical Institute, Stanford University, Stanford, CA 94305, USA
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA
| | - Stephen R Quake
- Department of Bioengineering, Stanford University, Stanford, CA 94305, USA.
- Department of Applied Physics, Stanford University, Stanford, CA 94305, USA
- Chan Zuckerberg Biohub, Stanford, CA 94305, USA
| | - Liqun Luo
- Department of Biology, Stanford University, Stanford, CA 94305, USA.
- Howard Hughes Medical Institute, Stanford University, Stanford, CA 94305, USA
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14
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Vijayalingam S, Ezekiel UR, Xu F, Subramanian T, Geerling E, Hoelscher B, San K, Ganapathy A, Pemberton K, Tycksen E, Pinto AK, Brien JD, Beck DB, Chung WK, Gurnett CA, Chinnadurai G. Human iPSC-Derived Neuronal Cells From CTBP1-Mutated Patients Reveal Altered Expression of Neurodevelopmental Gene Networks. Front Neurosci 2020; 14:562292. [PMID: 33192249 PMCID: PMC7653094 DOI: 10.3389/fnins.2020.562292] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 10/01/2020] [Indexed: 11/17/2022] Open
Abstract
A recurrent de novo mutation in the transcriptional corepressor CTBP1 is associated with neurodevelopmental disabilities in children (Beck et al., 2016, 2019; Sommerville et al., 2017). All reported patients harbor a single recurrent de novo heterozygous missense mutation (p.R342W) within the cofactor recruitment domain of CtBP1. To investigate the transcriptional activity of the pathogenic CTBP1 mutant allele in physiologically relevant human cell models, we generated induced pluripotent stem cells (iPSC) from the dermal fibroblasts derived from patients and normal donors. The transcriptional profiles of the iPSC-derived “early” neurons were determined by RNA-sequencing. Comparison of the RNA-seq data of the neurons from patients and normal donors revealed down regulation of gene networks involved in neurodevelopment, synaptic adhesion and anti-viral (interferon) response. Consistent with the altered gene expression patterns, the patient-derived neurons exhibited morphological and electrophysiological abnormalities, and susceptibility to viral infection. Taken together, our studies using iPSC-derived neuron models provide novel insights into the pathological activities of the CTBP1 p.R342W allele.
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Affiliation(s)
- S Vijayalingam
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, Edward A. Doisy Research Center, St. Louis, MO, United States
| | - Uthayashanker R Ezekiel
- Department of Clinical Health Sciences, Doisy College of Health Science, Saint Louis University School of Medicine, Saint Louis, MO, United States
| | - Fenglian Xu
- Department of Biology and Henry and Amelia Nasrallah Center for Neuroscience, Saint Louis University, St. Louis, MO, United States
| | - T Subramanian
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, Edward A. Doisy Research Center, St. Louis, MO, United States
| | - Elizabeth Geerling
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, Edward A. Doisy Research Center, St. Louis, MO, United States
| | - Brittany Hoelscher
- Department of Biology and Henry and Amelia Nasrallah Center for Neuroscience, Saint Louis University, St. Louis, MO, United States
| | - KayKay San
- Department of Clinical Health Sciences, Doisy College of Health Science, Saint Louis University School of Medicine, Saint Louis, MO, United States
| | - Aravinda Ganapathy
- Department of Clinical Health Sciences, Doisy College of Health Science, Saint Louis University School of Medicine, Saint Louis, MO, United States
| | - Kyle Pemberton
- Department of Biology and Henry and Amelia Nasrallah Center for Neuroscience, Saint Louis University, St. Louis, MO, United States
| | - Eric Tycksen
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, United States
| | - Amelia K Pinto
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, Edward A. Doisy Research Center, St. Louis, MO, United States
| | - James D Brien
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, Edward A. Doisy Research Center, St. Louis, MO, United States
| | - David B Beck
- National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, United States
| | - Wendy K Chung
- Department of Pediatrics and Medicine, Columbia University Medical Center, New York, NY, United States
| | - Christina A Gurnett
- Department of Neurology, Washington University School of Medicine, St. Louis, MO, United States
| | - G Chinnadurai
- Department of Molecular Microbiology and Immunology, Saint Louis University School of Medicine, Edward A. Doisy Research Center, St. Louis, MO, United States
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15
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Fujita H, Kodama T, du Lac S. Modular output circuits of the fastigial nucleus for diverse motor and nonmotor functions of the cerebellar vermis. eLife 2020; 9:e58613. [PMID: 32639229 PMCID: PMC7438114 DOI: 10.7554/elife.58613] [Citation(s) in RCA: 126] [Impact Index Per Article: 31.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 07/07/2020] [Indexed: 12/12/2022] Open
Abstract
The cerebellar vermis, long associated with axial motor control, has been implicated in a surprising range of neuropsychiatric disorders and cognitive and affective functions. Remarkably little is known, however, about the specific cell types and neural circuits responsible for these diverse functions. Here, using single-cell gene expression profiling and anatomical circuit analyses of vermis output neurons in the mouse fastigial (medial cerebellar) nucleus, we identify five major classes of glutamatergic projection neurons distinguished by gene expression, morphology, distribution, and input-output connectivity. Each fastigial cell type is connected with a specific set of Purkinje cells and inferior olive neurons and in turn innervates a distinct collection of downstream targets. Transsynaptic tracing indicates extensive disynaptic links with cognitive, affective, and motor forebrain circuits. These results indicate that diverse cerebellar vermis functions could be mediated by modular synaptic connections of distinct fastigial cell types with posturomotor, oromotor, positional-autonomic, orienting, and vigilance circuits.
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Affiliation(s)
- Hirofumi Fujita
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins UniversityBaltimoreUnited States
| | - Takashi Kodama
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins UniversityBaltimoreUnited States
| | - Sascha du Lac
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins UniversityBaltimoreUnited States
- Department of Neuroscience, Johns Hopkins UniversityBaltimoreUnited States
- Department of Neurology, Johns Hopkins Medical InstituteBaltimoreUnited States
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16
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Curtis D, Bakaya K, Sharma L, Bandyopadhyay S. Weighted burden analysis of exome-sequenced late-onset Alzheimer's cases and controls provides further evidence for a role for PSEN1 and suggests involvement of the PI3K/Akt/GSK-3β and WNT signalling pathways. Ann Hum Genet 2020; 84:291-302. [PMID: 32020597 DOI: 10.1111/ahg.12375] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 11/07/2019] [Accepted: 12/18/2019] [Indexed: 08/01/2024]
Abstract
Previous studies have implicated common and rare genetic variants as risk factors for late-onset Alzheimer's disease (LOAD). Here, weighted burden analysis was applied to over 10,000 exome-sequenced subjects from the Alzheimer's Disease Sequencing Project. Analyses were carried out to investigate whether rare variants predicted to have a functional effect within a gene were more commonly seen in cases or in controls. Confirmatory results were obtained for TREM2, ABCA7, and SORL1. Additional support was provided for PSEN1 (p = 0.0002), which previously had been only weakly implicated in LOAD. There was suggestive evidence that functional variants in PIK3R1, WNT7A, C1R, and EXOC5 might increase risk and that variants in TIAF1 and/or NDRG2 might have a protective effect. Overall, there was strong evidence (p = 5 × 10-6 ) that variants in tyrosine phosphatase genes reduce the risk of developing LOAD. Because PIK3R1 variants are expected to impair PI3K/Akt/GSK-3β signalling while variants in tyrosine phosphatase genes would enhance it, these findings are in line with those from animal models, suggesting that this pathway is protective against Alzheimer's disease.
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Affiliation(s)
- David Curtis
- UCL Genetics Institute, UCL, London, WC1E 6BT, United Kingdom
- Centre for Psychiatry, Queen Mary University of London, London, EC1M 6BQ, United Kingdom
| | - Kaushiki Bakaya
- UCL Genetics Institute, UCL, London, WC1E 6BT, United Kingdom
| | - Leona Sharma
- UCL Genetics Institute, UCL, London, WC1E 6BT, United Kingdom
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