51
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Popovitchenko T, Rasin MR. Transcriptional and Post-Transcriptional Mechanisms of the Development of Neocortical Lamination. Front Neuroanat 2017; 11:102. [PMID: 29170632 PMCID: PMC5684109 DOI: 10.3389/fnana.2017.00102] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2017] [Accepted: 10/25/2017] [Indexed: 12/31/2022] Open
Abstract
The neocortex is a laminated brain structure that is the seat of higher cognitive capacity and responses, long-term memory, sensory and emotional functions, and voluntary motor behavior. Proper lamination requires that progenitor cells give rise to a neuron, that the immature neuron can migrate away from its mother cell and past other cells, and finally that the immature neuron can take its place and adopt a mature identity characterized by connectivity and gene expression; thus lamination proceeds through three steps: genesis, migration, and maturation. Each neocortical layer contains pyramidal neurons that share specific morphological and molecular characteristics that stem from their prenatal birth date. Transcription factors are dynamic proteins because of the cohort of downstream factors that they regulate. RNA-binding proteins are no less dynamic, and play important roles in every step of mRNA processing. Indeed, recent screens have uncovered post-transcriptional mechanisms as being integral regulatory mechanisms to neocortical development. Here, we summarize major aspects of neocortical laminar development, emphasizing transcriptional and post-transcriptional mechanisms, with the aim of spurring increased understanding and study of its intricacies.
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Affiliation(s)
- Tatiana Popovitchenko
- Neuroscience and Cell Biology, Robert Wood Johnson Medical School, New Brunswick, NJ, United States
| | - Mladen-Roko Rasin
- Neuroscience and Cell Biology, Robert Wood Johnson Medical School, New Brunswick, NJ, United States
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52
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Baser A, Skabkin M, Martin-Villalba A. Neural Stem Cell Activation and the Role of Protein Synthesis. Brain Plast 2017; 3:27-41. [PMID: 29765858 PMCID: PMC5928545 DOI: 10.3233/bpl-160038] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Adult neural stem cells are generated at embryonic stages by entering a quiescent state that allows their retention into adulthood and thereby maintenance of life-long brain homeostasis. Thus, a tight balance between the quiescence and activation state is instrumental to meet the brain demands for a specific cell type at the correct numbers, at a given time and position. Protein synthesis is the most energy-consuming process within the cell and, not surprisingly, it occurs at low rates in quiescent stem cells. This way quiescent cells adjust to energy constraints and avoid their premature depletion. Stem cell activation is characterized by upregulation of protein synthesis followed by cell division and differentiation. The role of such upregulation as causative or rather a consequence of the activation remains elusive. Here we summarize recent findings connecting stem cell activation to the regulation of protein synthesis, particularly focusing on embryonic and adult neural stem cells of the ventricular zone.
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Affiliation(s)
- Avni Baser
- Molecular Neurobiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Maxim Skabkin
- Molecular Neurobiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Ana Martin-Villalba
- Molecular Neurobiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
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53
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Lennox AL, Mao H, Silver DL. RNA on the brain: emerging layers of post-transcriptional regulation in cerebral cortex development. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2017; 7. [PMID: 28837264 DOI: 10.1002/wdev.290] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 07/19/2017] [Accepted: 07/20/2017] [Indexed: 12/11/2022]
Abstract
Embryonic development is a critical period during which neurons of the brain are generated and organized. In the developing cerebral cortex, this requires complex processes of neural progenitor proliferation, neuronal differentiation, and migration. Each step relies upon highly regulated control of gene expression. In particular, RNA splicing, stability, localization, and translation have emerged as key post-transcriptional regulatory nodes of mouse corticogenesis. Trans-regulators of RNA metabolism, including microRNAs (miRs) and RNA-binding proteins (RBPs), orchestrate diverse steps of cortical development. These trans-factors function either individually or cooperatively to influence RNAs, often of similar classes, termed RNA regulons. New technological advances raise the potential for an increasingly sophisticated understanding of post-transcriptional control in the developing neocortex. Many RNA-binding factors are also implicated in neurodevelopmental diseases of the cortex. Therefore, elucidating how RBPs and miRs converge to influence mRNA expression in progenitors and neurons will give valuable insights into mechanisms of cortical development and disease. WIREs Dev Biol 2018, 7:e290. doi: 10.1002/wdev.290 This article is categorized under: Gene Expression and Transcriptional Hierarchies > Regulatory RNA Nervous System Development > Vertebrates: Regional Development Adult Stem Cells, Tissue Renewal, and Regeneration > Stem Cells and Disease.
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Affiliation(s)
- Ashley L Lennox
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, USA
| | - Hanqian Mao
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, USA.,Department of Cell Biology and Physiology, University of North Carolina, Chapel Hill, NC, USA
| | - Debra L Silver
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, USA.,Department of Cell Biology, Duke University Medical Center, Durham, NC, USA.,Department of Neurobiology, Duke University Medical Center, Durham, NC, USA
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54
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Abstract
Background Autism spectrum disorders (ASD) are etiologically heterogeneous and complex. Functional genomics work has begun to identify a diverse array of dysregulated transcriptomic programs (e.g., synaptic, immune, cell cycle, DNA damage, WNT signaling, cortical patterning and differentiation) potentially involved in ASD brain abnormalities during childhood and adulthood. However, it remains unclear whether such diverse dysregulated pathways are independent of each other or instead reflect coordinated hierarchical systems-level pathology. Methods Two ASD cortical transcriptome datasets were re-analyzed using consensus weighted gene co-expression network analysis (WGCNA) to identify common co-expression modules across datasets. Linear mixed-effect models and Bayesian replication statistics were used to identify replicable differentially expressed modules. Eigengene network analysis was then utilized to identify between-group differences in how co-expression modules interact and cluster into hierarchical meta-modular organization. Protein-protein interaction analyses were also used to determine whether dysregulated co-expression modules show enhanced interactions. Results We find replicable evidence for 10 gene co-expression modules that are differentially expressed in ASD cortex. Rather than being independent non-interacting sources of pathology, these dysregulated co-expression modules work in synergy and physically interact at the protein level. These systems-level transcriptional signals are characterized by downregulation of synaptic processes coordinated with upregulation of immune/inflammation, response to other organism, catabolism, viral processes, translation, protein targeting and localization, cell proliferation, and vasculature development. Hierarchical organization of meta-modules (clusters of highly correlated modules) is also highly affected in ASD. Conclusions These findings highlight that dysregulation of the ASD cortical transcriptome is characterized by the dysregulation of multiple coordinated transcriptional programs producing synergistic systems-level effects that cannot be fully appreciated by studying the individual component biological processes in isolation. Electronic supplementary material The online version of this article (doi:10.1186/s13229-017-0147-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Michael V Lombardo
- Department of Psychology and Center for Applied Neuroscience, University of Cyprus, Nicosia, Cyprus.,Autism Research Centre, Department of Psychiatry, University of Cambridge, Cambridge, UK
| | - Eric Courchesne
- Department of Neurosciences, UC San Diego Autism Center, School of Medicine University of California, San Diego, La Jolla, CA USA
| | - Nathan E Lewis
- Department of Pediatrics, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA USA.,Novo Nordisk Foundation Center for Biosustainability at the University of California, San Diego, La Jolla, CA USA
| | - Tiziano Pramparo
- Department of Neurosciences, UC San Diego Autism Center, School of Medicine University of California, San Diego, La Jolla, CA USA
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55
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Kanemitsu Y, Fujitani M, Fujita Y, Zhang S, Su YQ, Kawahara Y, Yamashita T. The RNA-binding protein MARF1 promotes cortical neurogenesis through its RNase activity domain. Sci Rep 2017; 7:1155. [PMID: 28442784 PMCID: PMC5430739 DOI: 10.1038/s41598-017-01317-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Accepted: 03/27/2017] [Indexed: 01/14/2023] Open
Abstract
Cortical neurogenesis is a fundamental process of brain development that is spatiotemporally regulated by both intrinsic and extrinsic cues. Although recent evidence has highlighted the significance of transcription factors in cortical neurogenesis, little is known regarding the role of RNA-binding proteins (RBPs) in the post-transcriptional regulation of cortical neurogenesis. Here, we report that meiosis arrest female 1 (MARF1) is an RBP that is expressed during neuronal differentiation. Cortical neurons expressed the somatic form of MARF1 (sMARF1) but not the oocyte form (oMARF1). sMARF1 was enriched in embryonic brains, and its expression level decreased as brain development progressed. Overexpression of sMARF1 in E12.5 neuronal progenitor cells promoted neuronal differentiation, whereas sMARF1 knockdown decreased neuronal progenitor differentiation in vitro. We also examined the function of sMARF1 in vivo using an in utero electroporation technique. Overexpression of sMARF1 increased neuronal differentiation, whereas knockdown of sMARF1 inhibited differentiation in vivo. Moreover, using an RNase domain deletion mutant of sMARF1, we showed that the RNase domain is required for the effects of sMARF1 on cortical neurogenesis in vitro. Our results further elucidate the mechanisms of post-transcriptional regulation of cortical neurogenesis by RBPs.
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Affiliation(s)
- Yoshitaka Kanemitsu
- Department of Molecular Neuroscience, Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka, 565-0871, Japan.,Interdisciplinary Program for Biomedical Sciences, Osaka University, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Masashi Fujitani
- Department of Molecular Neuroscience, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan. .,Molecular Research Center for Children's Mental Development, United Graduate School of Child Development, Osaka University, 2-2 Yamadaoka, Suita, Osaka, 565-0872, Japan. .,Department of Anatomy and Neuroscience, Hyogo College of Medicine, 1-1, Mukogawa-cho, Nishinomiya, Hyogo, 663-8501, Japan.
| | - Yuki Fujita
- Department of Molecular Neuroscience, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Suxiang Zhang
- Department of Molecular Neuroscience, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - You-Qiang Su
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, 140 Hanzhong Road, Nanjing, 210029, Jiangsu Province, China
| | - Yukio Kawahara
- Department of RNA Biology and Neuroscience, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan
| | - Toshihide Yamashita
- Department of Molecular Neuroscience, Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, Suita, Osaka, 565-0871, Japan. .,Department of Molecular Neuroscience, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan.
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56
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Pilaz LJ, Silver DL. Moving messages in the developing brain-emerging roles for mRNA transport and local translation in neural stem cells. FEBS Lett 2017; 591:1526-1539. [PMID: 28304078 DOI: 10.1002/1873-3468.12626] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 03/06/2017] [Accepted: 03/11/2017] [Indexed: 11/10/2022]
Abstract
The mammalian cerebral cortex is a complex brain structure integral to our higher cognition. During embryonic cortical development, radial glial progenitors (RGCs) produce neurons and serve as physical structures for migrating neurons. Recent discoveries highlight new roles for RNA localization and local translation in RGCs, both at the cell body and at distal structures called basal endfeet. By implementing technologies from the field of RNA research to brain development, investigators can manipulate RNA-binding proteins as well as visualize single-molecule RNAs, live movement of mRNAs and their binding proteins, and translation. Going forward, these studies establish a framework for investigating how post-transcriptional RNA regulation helps shape RGC function and triggers neurodevelopmental diseases.
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Affiliation(s)
- Louis-Jan Pilaz
- Department of Molecular Genetics and Microbiology, Regeneration Next, Duke University Medical Center, Durham, NC, USA
| | - Debra L Silver
- Department of Molecular Genetics and Microbiology, Regeneration Next, Duke University Medical Center, Durham, NC, USA.,Department of Cell Biology, Duke University Medical Center, Durham, NC, USA.,Department of Neurobiology, Duke University Medical Center, Durham, NC, USA.,Duke Institute for Brain Sciences, Duke University Medical Center, Durham, NC, USA
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57
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Yuzwa SA, Miller FD. Deciphering cell-cell communication in the developing mammalian brain. NEUROGENESIS 2017; 4:e1286425. [PMID: 28265587 DOI: 10.1080/23262133.2017.1286425] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 01/08/2017] [Accepted: 01/16/2017] [Indexed: 10/20/2022]
Abstract
The diverse subtypes of neurons that comprise the mammalian cerebral cortex are produced from a single population of cortical neural precursor cells during the period of embryonic neurogenesis. While this process of neurogenesis is tightly controlled at the transcriptional and translational levels, substantial opportunity exists for extrinsic or niche control of the process of neurogenesis. In our recently published work we made use of a combination of computational and biologic approaches to characterize cell-cell communication between cortical neurons and cortical precursor cells and thereby reveal an unexpectedly complex growth factor communication network that accurately predicted new regulators of cortical neurogenesis.
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Affiliation(s)
- Scott A Yuzwa
- Program in Neurosciences and Mental Health, Hospital for Sick Children , Toronto, Canada
| | - Freda D Miller
- Program in Neurosciences and Mental Health, Hospital for Sick Children, Toronto, Canada; Institute of Medical Sciences, University of Toronto, Toronto, Canada; Molecular Genetics, University of Toronto, Toronto, Canada; Physiology, University of Toronto, Toronto, Canada
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58
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Kraushar ML, Popovitchenko T, Volk NL, Rasin MR. The frontier of RNA metamorphosis and ribosome signature in neocortical development. Int J Dev Neurosci 2016; 55:131-139. [PMID: 27241046 PMCID: PMC5124555 DOI: 10.1016/j.ijdevneu.2016.02.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Revised: 02/26/2016] [Accepted: 02/28/2016] [Indexed: 12/14/2022] Open
Abstract
More than a passive effector of gene expression, mRNA translation (protein synthesis) by the ribosome is a rapidly tunable and dynamic molecular mechanism. Neurodevelopmental disorders are associated with abnormalities in mRNA translation, protein synthesis, and neocortical development; yet, we know little about the molecular mechanisms underlying these abnormalities. Furthermore, our understanding of regulation of the ribosome and mRNA translation during normal brain development is only in its early stages. mRNA translation is emerging as a key driver of the rapid and timed regulation of spatiotemporal gene expression in the developing nervous system, including the neocortex. In this review, we focus on the regulatory role of the ribosome in neocortical development, and construct a current understanding of how ribosomal complex specificity may contribute to the development of the neocortex. We also present a microarray analysis of ribosomal protein-coding mRNAs across the neurogenic phase of neocortical development, in addition to the dynamic enrichment of these mRNAs in actively translating neocortical polysomal ribosomes. Understanding the multivariate control of mRNA translation by ribosomal complex specificity will be critical to reveal the intricate mechanisms of normal brain development and pathologies of neurodevelopmental disorders.
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Affiliation(s)
- Matthew L Kraushar
- Department of Neuroscience and Cell Biology, Rutgers University, Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA
| | - Tatiana Popovitchenko
- Department of Neuroscience and Cell Biology, Rutgers University, Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA
| | - Nicole L Volk
- Department of Neuroscience and Cell Biology, Rutgers University, Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA
| | - Mladen-Roko Rasin
- Department of Neuroscience and Cell Biology, Rutgers University, Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA.
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59
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Beyond the survival and death of the deltamethrin-threatened pollen beetle Meligethes aeneus: An in-depth proteomic study employing a transcriptome database. J Proteomics 2016; 150:281-289. [PMID: 27705816 DOI: 10.1016/j.jprot.2016.09.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Revised: 09/10/2016] [Accepted: 09/28/2016] [Indexed: 12/18/2022]
Abstract
Insecticide resistance is an increasingly global problem that hampers pest control. We sought the mechanism responsible for survival following pyrethroid treatment and the factors connected to paralysis/death of the pollen beetle Meligethes aeneus through a proteome-level analysis using nanoLC coupled with Orbitrap Fusion™ Tribrid™ mass spectrometry. A tolerant field population of beetles was treated with deltamethrin, and the ensuing proteome changes were observed in the survivors (resistant), dead (paralyzed) and control-treated beetles. The protein database consisted of the translated transcriptome, and the resulting changes were manually annotated via BLASTP. We identified a number of high-abundance changes in which there were several dominant proteins, e.g., the electron carrier cytochrome b5, ribosomal proteins 60S RPL28, 40S RPS23 and RPS26, eIF4E-transporter, anoxia up-regulated protein, 2 isoforms of vitellogenin and pathogenesis-related protein 5. Deltamethrin detoxification was influenced by different cytochromes P450, which were likely boosted by increased cytochrome b5, but glutathione-S-transferase ε and UDP-glucuronosyltransferases also contributed. Moreover, we observed changes in proteins related to RNA interference, RNA binding and epigenetic modifications. The high changes in ribosomal proteins and associated factors suggest specific control of translation. Overall, we showed modulation of expression processes by epigenetic markers, alternative splicing and translation. Future functional studies will benefit. BIOLOGICAL SIGNIFICANCE Insects develop pesticide resistance, which has become one of the key issues in plant protection. This growing resistance increases the demand for pesticide applications and the development of new substances. Knowledge in the field regarding the resistance mechanism and its responses to pesticide treatment provides us the opportunity to propose a solution for this issue. Although the pollen beetle Meligethes aeneus was effectively controlled with pyrethroids for many years, there have been reports of increasing resistance. We show protein changes including production of isoforms in response to deltamethrin at the protein level. These results illustrate the insect's survival state as a resistant beetle and in its paralyzed state (evaluated as dead) relative to resistant individuals.
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60
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Yang G, Cancino G, Zahr S, Guskjolen A, Voronova A, Gallagher D, Frankland P, Kaplan D, Miller F. A Glo1-Methylglyoxal Pathway that Is Perturbed in Maternal Diabetes Regulates Embryonic and Adult Neural Stem Cell Pools in Murine Offspring. Cell Rep 2016; 17:1022-1036. [DOI: 10.1016/j.celrep.2016.09.067] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2016] [Revised: 08/08/2016] [Accepted: 09/21/2016] [Indexed: 01/03/2023] Open
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Cancino GI, Fatt MP, Miller FD, Kaplan DR. Conditional ablation of p63 indicates that it is essential for embryonic development of the central nervous system. Cell Cycle 2016; 14:3270-81. [PMID: 26359534 PMCID: PMC4825551 DOI: 10.1080/15384101.2015.1087618] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
p63 is a member of the p53 family that regulates the survival of neural precursors in the adult brain. However, the relative importance of p63 in the developing brain is still unclear, since embryonic p63−/− mice display no apparent deficits in neural development. Here, we have used a more definitive conditional knockout mouse approach to address this issue, crossing p63fl/fl mice to mice carrying a nestin-CreERT2 transgene that drives inducible recombination in neural precursors following tamoxifen treatment. Inducible ablation of p63 following tamoxifen treatment of mice on embryonic day 12 resulted in highly perturbed forebrain morphology including a thinner cortex and enlarged lateral ventricles 3 d later. While the normal cortical layers were still present following acute p63 ablation, cortical precursors and neurons were both reduced in number due to widespread cellular apoptosis. This apoptosis was cell-autonomous, since it also occurred when p63 was inducibly ablated in primary cultured cortical precursors. Finally, we demonstrate increased expression of the mRNA encoding another p53 family member, ΔNp73, in cortical precursors of p63−/− but not tamoxifen-treated p63fl/fl;R26YFPfl/fl;nestin-CreERT2+/Ø embryos. Since ΔNp73 promotes cell survival, then this compensatory increase likely explains the lack of an embryonic brain phenotype in p63−/− mice. Thus, p63 plays a key prosurvival role in the developing mammalian brain.
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Affiliation(s)
- Gonzalo I Cancino
- a Program in Neurosciences and Mental Health, Hospital for Sick Children ; Toronto , ON Canada
| | - Michael P Fatt
- a Program in Neurosciences and Mental Health, Hospital for Sick Children ; Toronto , ON Canada.,b Institute of Medical Science, University of Toronto ; Toronto , ON Canada
| | - Freda D Miller
- a Program in Neurosciences and Mental Health, Hospital for Sick Children ; Toronto , ON Canada.,b Institute of Medical Science, University of Toronto ; Toronto , ON Canada.,c Departments of Physiology ; University of Toronto ; Toronto , ON Canada.,d Molecular Genetics, University of Toronto ; Toronto , ON Canada
| | - David R Kaplan
- a Program in Neurosciences and Mental Health, Hospital for Sick Children ; Toronto , ON Canada.,b Institute of Medical Science, University of Toronto ; Toronto , ON Canada.,d Molecular Genetics, University of Toronto ; Toronto , ON Canada
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62
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Signer RAJ, Qi L, Zhao Z, Thompson D, Sigova AA, Fan ZP, DeMartino GN, Young RA, Sonenberg N, Morrison SJ. The rate of protein synthesis in hematopoietic stem cells is limited partly by 4E-BPs. Genes Dev 2016; 30:1698-703. [PMID: 27492367 PMCID: PMC5002975 DOI: 10.1101/gad.282756.116] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2016] [Accepted: 07/18/2016] [Indexed: 01/23/2023]
Abstract
Adult stem cells must limit their rate of protein synthesis, but the underlying mechanisms remain largely unexplored. Differences in protein synthesis among hematopoietic stem cells (HSCs) and progenitor cells did not correlate with differences in proteasome activity, total RNA content, mRNA content, or cell division rate. However, adult HSCs had more hypophosphorylated eukaryotic initiation factor 4E-binding protein 1 (4E-BP1) and 4E-BP2 as compared with most other hematopoietic progenitors. Deficiency for 4E-BP1 and 4E-BP2 significantly increased global protein synthesis in HSCs, but not in other hematopoietic progenitors, and impaired their reconstituting activity, identifying a mechanism that promotes HSC maintenance by attenuating protein synthesis.
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Affiliation(s)
- Robert A J Signer
- Howard Hughes Medical Institute, Children's Research Institute, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA; Division of Regenerative Medicine, Department of Medicine, Moores Cancer Center, University of California at San Diego, La Jolla, California 92093, USA
| | - Le Qi
- Howard Hughes Medical Institute, Children's Research Institute, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
| | - Zhiyu Zhao
- Howard Hughes Medical Institute, Children's Research Institute, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
| | - David Thompson
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
| | - Alla A Sigova
- Whitehead Institute for Biomedical Research, Massachusetts Institute of Technology, Cambridge, Massachusetts 02142, USA
| | - Zi Peng Fan
- Whitehead Institute for Biomedical Research, Massachusetts Institute of Technology, Cambridge, Massachusetts 02142, USA
| | - George N DeMartino
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
| | - Richard A Young
- Whitehead Institute for Biomedical Research, Massachusetts Institute of Technology, Cambridge, Massachusetts 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Nahum Sonenberg
- Department of Biochemistry, Goodman Cancer Centre, McGill University, Montreal, Quebec H3A 1A3, Canada
| | - Sean J Morrison
- Howard Hughes Medical Institute, Children's Research Institute, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
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63
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EFHC1 variants in juvenile myoclonic epilepsy: reanalysis according to NHGRI and ACMG guidelines for assigning disease causality. Genet Med 2016; 19:144-156. [PMID: 27467453 DOI: 10.1038/gim.2016.86] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 05/09/2016] [Indexed: 12/12/2022] Open
Abstract
PURPOSE EFHC1 variants are the most common mutations in inherited myoclonic and grand mal clonic-tonic-clonic (CTC) convulsions of juvenile myoclonic epilepsy (JME). We reanalyzed 54 EFHC1 variants associated with epilepsy from 17 cohorts based on National Human Genome Research Institute (NHGRI) and American College of Medical Genetics and Genomics (ACMG) guidelines for interpretation of sequence variants. METHODS We calculated Bayesian LOD scores for variants in coinheritance, unconditional exact tests and odds ratios (OR) in case-control associations, allele frequencies in genome databases, and predictions for conservation/pathogenicity. We reviewed whether variants damage EFHC1 functions, whether efhc1-/- KO mice recapitulate CTC convulsions and "microdysgenesis" neuropathology, and whether supernumerary synaptic and dendritic phenotypes can be rescued in the fly model when EFHC1 is overexpressed. We rated strengths of evidence and applied ACMG combinatorial criteria for classifying variants. RESULTS Nine variants were classified as "pathogenic," 14 as "likely pathogenic," 9 as "benign," and 2 as "likely benign." Twenty variants of unknown significance had an insufficient number of ancestry-matched controls, but ORs exceeded 5 when compared with racial/ethnic-matched Exome Aggregation Consortium (ExAC) controls. CONCLUSIONS NHGRI gene-level evidence and variant-level evidence establish EFHC1 as the first non-ion channel microtubule-associated protein whose mutations disturb R-type VDCC and TRPM2 calcium currents in overgrown synapses and dendrites within abnormally migrated dislocated neurons, thus explaining CTC convulsions and "microdysgenesis" neuropathology of JME.Genet Med 19 2, 144-156.
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Kamenska A, Simpson C, Vindry C, Broomhead H, Bénard M, Ernoult-Lange M, Lee BP, Harries LW, Weil D, Standart N. The DDX6-4E-T interaction mediates translational repression and P-body assembly. Nucleic Acids Res 2016; 44:6318-34. [PMID: 27342281 PMCID: PMC5291280 DOI: 10.1093/nar/gkw565] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 06/10/2016] [Accepted: 06/14/2016] [Indexed: 12/13/2022] Open
Abstract
4E-Transporter binds eIF4E via its consensus sequence YXXXXLΦ, shared with eIF4G, and is a nucleocytoplasmic shuttling protein found enriched in P-(rocessing) bodies. 4E-T inhibits general protein synthesis by reducing available eIF4E levels. Recently, we showed that 4E-T bound to mRNA however represses its translation in an eIF4E-independent manner, and contributes to silencing of mRNAs targeted by miRNAs. Here, we address further the mechanism of translational repression by 4E-T by first identifying and delineating the interacting sites of its major partners by mass spectrometry and western blotting, including DDX6, UNR, unrip, PAT1B, LSM14A and CNOT4. Furthermore, we document novel binding between 4E-T partners including UNR-CNOT4 and unrip-LSM14A, altogether suggesting 4E-T nucleates a complex network of RNA-binding protein interactions. In functional assays, we demonstrate that joint deletion of two short conserved motifs that bind UNR and DDX6 relieves repression of 4E-T-bound mRNA, in part reliant on the 4E-T-DDX6-CNOT1 axis. We also show that the DDX6-4E-T interaction mediates miRNA-dependent translational repression and de novo P-body assembly, implying that translational repression and formation of new P-bodies are coupled processes. Altogether these findings considerably extend our understanding of the role of 4E-T in gene regulation, important in development and neurogenesis.
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Affiliation(s)
- Anastasiia Kamenska
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB21QW, UK
| | - Clare Simpson
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB21QW, UK
| | - Caroline Vindry
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB21QW, UK
| | - Helen Broomhead
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB21QW, UK
| | - Marianne Bénard
- Sorbonne Universités, UPMC, CNRS, IBPS, Developmental Biology Laboratory, 75005 Paris, France
| | - Michèle Ernoult-Lange
- Sorbonne Universités, UPMC, CNRS, IBPS, Developmental Biology Laboratory, 75005 Paris, France
| | - Benjamin P Lee
- Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, Barrack Road, Exeter EX2 5DW
| | - Lorna W Harries
- Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, Barrack Road, Exeter EX2 5DW
| | - Dominique Weil
- Sorbonne Universités, UPMC, CNRS, IBPS, Developmental Biology Laboratory, 75005 Paris, France
| | - Nancy Standart
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB21QW, UK
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65
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Solso S, Xu R, Proudfoot J, Hagler DJ, Campbell K, Venkatraman V, Barnes CC, Ahrens-Barbeau C, Pierce K, Dale A, Eyler L, Courchesne E. Diffusion Tensor Imaging Provides Evidence of Possible Axonal Overconnectivity in Frontal Lobes in Autism Spectrum Disorder Toddlers. Biol Psychiatry 2016; 79:676-84. [PMID: 26300272 PMCID: PMC4699869 DOI: 10.1016/j.biopsych.2015.06.029] [Citation(s) in RCA: 104] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Revised: 06/22/2015] [Accepted: 06/23/2015] [Indexed: 12/31/2022]
Abstract
BACKGROUND Theories of brain abnormality in autism spectrum disorder (ASD) have focused on underconnectivity as an explanation for social, language, and behavioral deficits but are based mainly on studies of older autistic children and adults. METHODS In 94 ASD and typical toddlers ages 1 to 4 years, we examined the microstructure (indexed by fractional anisotropy) and volume of axon pathways using in vivo diffusion tensor imaging of fronto-frontal, fronto-temporal, fronto-striatal, and fronto-amygdala axon pathways, as well as posterior contrast tracts. Differences between ASD and typical toddlers in the nature of the relationship of age to these measures were tested. RESULTS Frontal tracts in ASD toddlers displayed abnormal age-related changes with greater fractional anisotropy and volume than normal at younger ages but an overall slower than typical apparent rate of continued development across the span of years. Posterior cortical contrast tracts had few significant abnormalities. CONCLUSIONS Frontal fiber tracts displayed deviant early development and age-related changes that could underlie impaired brain functioning and impact social and communication behaviors in ASD.
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Affiliation(s)
- Stephanie Solso
- Department of Neuroscience, School of Medicine, University of California San Diego, La Jolla, CA 92093
| | - Ronghui Xu
- CTRI, School of Medicine, University of California San Diego, La Jolla, CA 92093
| | - James Proudfoot
- CTRI, School of Medicine, University of California San Diego, La Jolla, CA 92093
| | - Donald J. Hagler
- Department of Radiology, Multimodal Imaging Laboratory, School of Medicine, University of California San Diego, La Jolla, CA 92093
| | - Kathleen Campbell
- Department of Neuroscience, School of Medicine, University of California San Diego, La Jolla, CA 92093
| | - Vijay Venkatraman
- Department of Radiology, Multimodal Imaging Laboratory, School of Medicine, University of California San Diego, La Jolla, CA 92093
| | - Cynthia Carter Barnes
- Department of Neuroscience, School of Medicine, University of California San Diego, La Jolla, CA 92093
| | - Clelia Ahrens-Barbeau
- Department of Neuroscience, School of Medicine, University of California San Diego, La Jolla, CA 92093
| | - Karen Pierce
- Department of Neuroscience, School of Medicine, University of California San Diego, La Jolla, CA 92093
| | - Anders Dale
- Department of Neuroscience, School of Medicine, University of California San Diego, La Jolla, CA 92093,Department of Radiology, Multimodal Imaging Laboratory, School of Medicine, University of California San Diego, La Jolla, CA 92093
| | - Lisa Eyler
- Department of Neuroscience, School of Medicine, University of California San Diego, La Jolla, CA 92093,Department of Psychiatry, School of Medicine, University of California San Diego, La Jolla, CA 92093,Desert-Pacific Mental Illness Research, Education and Clinical Center, VA San Diego Healthcare System, San Diego, CA 92161
| | - Eric Courchesne
- Department of Neuroscience, School of Medicine, University of California San Diego, La Jolla.
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66
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A Smaug2-Based Translational Repression Complex Determines the Balance between Precursor Maintenance versus Differentiation during Mammalian Neurogenesis. J Neurosci 2016; 35:15666-81. [PMID: 26609159 DOI: 10.1523/jneurosci.2172-15.2015] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
UNLABELLED Here, we have asked about post-transcriptional mechanisms regulating murine developmental neurogenesis, focusing upon the RNA-binding proteins Smaug2 and Nanos1. We identify, in embryonic neural precursors of the murine cortex, a Smaug2 protein/nanos1 mRNA complex that is present in cytoplasmic granules with the translational repression proteins Dcp1 and 4E-T. We show that Smaug2 inhibits and Nanos1 promotes neurogenesis, with Smaug2 knockdown enhancing neurogenesis and depleting precursors, and Nanos1 knockdown inhibiting neurogenesis and maintaining precursors. Moreover, we show that Smaug2 likely regulates neurogenesis by silencing nanos1 mRNA. Specifically, Smaug2 knockdown inappropriately increases Nanos1 protein, and the Smaug2 knockdown-mediated neurogenesis is rescued by preventing this increase. Thus, Smaug2 and Nanos1 function as a bimodal translational repression switch to control neurogenesis, with Smaug2 acting in transcriptionally primed precursors to silence mRNAs important for neurogenesis, including nanos1 mRNA, and Nanos1 acting during the transition to neurons to repress the precursor state. SIGNIFICANCE STATEMENT The mechanisms instructing neural stem cells to generate the appropriate progeny are still poorly understood. Here, we show that the RNA-binding proteins Smaug2 and Nanos1 are critical regulators of this balance and provide evidence supporting the idea that neural precursors are transcriptionally primed to generate neurons but translational regulation maintains these precursors in a stem cell state until the appropriate developmental time.
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67
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Packer A. Neocortical neurogenesis and the etiology of autism spectrum disorder. Neurosci Biobehav Rev 2016; 64:185-95. [PMID: 26949225 DOI: 10.1016/j.neubiorev.2016.03.002] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 02/29/2016] [Accepted: 03/01/2016] [Indexed: 12/11/2022]
Abstract
Researchers have now identified many highly penetrant genetic risk factors for autism spectrum disorder (ASD). Some of these genes encode synaptic proteins, lending support to the hypothesis that ASD is a disorder of synaptic homeostasis. Less attention, however, has been paid to the genetic risk factors that converge on events that precede synaptogenesis, including the proliferation of neural progenitor cells and the migration of neurons to the appropriate layers of the developing neocortex. Here I review this evidence, focusing on studies of mutant mouse phenotypes, human postmortem data, systems biological analyses, and non-genetic risk factors. These findings highlight embryonic neurogenesis as a potentially important locus of pathology in ASD. In some instances, this pathology may be driven by alterations in chromatin biology and canonical Wnt signaling, which in turn affect fundamental cellular processes such as cell-cycle length and cell migration. This view of ASD suggests the need for a better understanding of the relationship between variation in neuron number, laminar composition, and the neural circuitry most relevant to the disorder.
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Affiliation(s)
- Alan Packer
- Simons Foundation Autism Research Initiative, 160 Fifth Avenue, New York, NY 10010, USA.
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68
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Ozgur S, Basquin J, Kamenska A, Filipowicz W, Standart N, Conti E. Structure of a Human 4E-T/DDX6/CNOT1 Complex Reveals the Different Interplay of DDX6-Binding Proteins with the CCR4-NOT Complex. Cell Rep 2015; 13:703-711. [DOI: 10.1016/j.celrep.2015.09.033] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 08/05/2015] [Accepted: 09/10/2015] [Indexed: 01/09/2023] Open
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69
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Gil-Sanz C, Espinosa A, Fregoso SP, Bluske KK, Cunningham CL, Martinez-Garay I, Zeng H, Franco SJ, Müller U. Lineage Tracing Using Cux2-Cre and Cux2-CreERT2 Mice. Neuron 2015; 86:1091-1099. [PMID: 25996136 DOI: 10.1016/j.neuron.2015.04.019] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Revised: 12/15/2014] [Accepted: 03/30/2015] [Indexed: 10/23/2022]
Abstract
Using genetic fate-mapping with Cux2-Cre and Cux2-CreERT2 mice we demonstrated that the neocortical ventricular zone (VZ) contains radial glial cells (RGCs) with restricted fate potentials (Franco et al., 2012). Using the same mouse lines, Guo et al. (2013) concluded that the neocortical VZ does not contain lineage-restricted RGCs. We now show that the recombination pattern in Cux2-Cre/CreERT2 mice depends on genetic background and breeding strategies. We provide evidence that Guo et al. likely reached different conclusions because they worked with transgenic sublines with drifted transgene expression patterns. In Cux2-Cre and Cux2-CreERT2 mice that recapitulate the endogenous Cux2 expression pattern, the vast majority of fate-mapped neurons express Satb2 but not Ctip2, confirming that a restricted subset of all neocortical projection neurons belongs to the Cux2 lineage. This Matters Arising paper is in response to Guo et al. (2013), published in Neuron. See also the Matters Arising Response paper by Eckler et al. (2015), published concurrently with this Matters Arising in Neuron.
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Affiliation(s)
- Cristina Gil-Sanz
- Molecular and Cellular Neuroscience Department, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Ana Espinosa
- Molecular and Cellular Neuroscience Department, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Santiago P Fregoso
- Graduate Program in Cell Biology, Stem Cells and Development, University of Colorado School of Medicine, Aurora, CO 80045, USA
| | - Krista K Bluske
- Molecular and Cellular Neuroscience Department, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Christopher L Cunningham
- Molecular and Cellular Neuroscience Department, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Isabel Martinez-Garay
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford OX1 3QX, UK
| | - Hongkui Zeng
- Allen Institute for Brain Science, Seattle, WA 98103, USA
| | - Santos J Franco
- Graduate Program in Cell Biology, Stem Cells and Development, University of Colorado School of Medicine, Aurora, CO 80045, USA; Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO 80045, USA; Program of Pediatric Stem Cell Biology, Children's Hospital Colorado, Aurora, CO 80045, USA.
| | - Ulrich Müller
- Molecular and Cellular Neuroscience Department, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, CA 92037, USA.
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70
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Pilaz LJ, Silver DL. Post-transcriptional regulation in corticogenesis: how RNA-binding proteins help build the brain. WILEY INTERDISCIPLINARY REVIEWS-RNA 2015; 6:501-15. [PMID: 26088328 DOI: 10.1002/wrna.1289] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 05/01/2015] [Accepted: 05/01/2015] [Indexed: 12/17/2022]
Abstract
The cerebral cortex, the brain structure responsible for our higher cognitive functions, is built during embryonic development in a process called corticogenesis. During corticogenesis, neural stem cells generate distinct populations of progenitors and excitatory neurons. These new neurons migrate radially in the cortex, eventually forming neuronal layers and establishing synaptic connections with other neurons both within and outside the cortex. Perturbations to corticogenesis can result in severe neurodevelopmental disorders, thus emphasizing the need to better understand molecular regulation of brain development. Recent studies in both model organisms and humans have collectively highlighted roles for post-transcriptional regulation in virtually all steps of corticogenesis. Genomic approaches have revealed global RNA changes associated with spatial and temporal regulation of cortical development. Additionally, genetic studies have uncovered RNA-binding proteins (RBPs) critical for cell proliferation, differentiation, and migration within the developing neocortex. Many of these same RBPs play causal roles in neurodevelopmental pathologies. In the developing neocortex, RBPs influence diverse steps of mRNA metabolism, including splicing, stability, translation, and localization. With the advent of new technologies, researchers have begun to uncover key transcripts regulated by these RBPs. Given the complexity of the developing mammalian cortex, a major challenge for the future will be to understand how dynamic RNA regulation occurs within heterogeneous cell populations, across space and time. In sum, post-transcriptional regulation has emerged as a critical mechanism for driving corticogenesis and exciting direction of future research.
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Affiliation(s)
- Louis-Jan Pilaz
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, USA
| | - Debra L Silver
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, NC, USA.,Department of Cell Biology, Duke University Medical Center, Durham, NC, USA.,Department of Neurobiology, Duke University Medical Center, Durham, NC, USA.,Duke Institute for Brain Sciences, Duke University Medical Center, Durham, NC, USA
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71
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Nishimura T, Padamsi Z, Fakim H, Milette S, Dunham W, Gingras AC, Fabian M. The eIF4E-Binding Protein 4E-T Is a Component of the mRNA Decay Machinery that Bridges the 5′ and 3′ Termini of Target mRNAs. Cell Rep 2015; 11:1425-36. [DOI: 10.1016/j.celrep.2015.04.065] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 04/17/2015] [Accepted: 04/30/2015] [Indexed: 12/26/2022] Open
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72
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Gigek CO, Chen ES, Ota VK, Maussion G, Peng H, Vaillancourt K, Diallo AB, Lopez JP, Crapper L, Vasuta C, Chen GG, Ernst C. A molecular model for neurodevelopmental disorders. Transl Psychiatry 2015; 5:e565. [PMID: 25966365 PMCID: PMC4471287 DOI: 10.1038/tp.2015.56] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 03/24/2015] [Indexed: 01/24/2023] Open
Abstract
Genes implicated in neurodevelopmental disorders (NDDs) important in cognition and behavior may have convergent function and several cellular pathways have been implicated, including protein translational control, chromatin modification, and synapse assembly and maintenance. Here, we test the convergent effects of methyl-CpG binding domain 5 (MBD5) and special AT-rich binding protein 2 (SATB2) reduced dosage in human neural stem cells (NSCs), two genes implicated in 2q23.1 and 2q33.1 deletion syndromes, respectively, to develop a generalized model for NDDs. We used short hairpin RNA stably incorporated into healthy neural stem cells to supress MBD5 and SATB2 expression, and massively parallel RNA sequencing, DNA methylation sequencing and microRNA arrays to test the hypothesis that a primary etiology of NDDs is the disruption of the balance of NSC proliferation and differentiation. We show that reduced dosage of either gene leads to significant overlap of gene-expression patterns, microRNA patterns and DNA methylation states with control NSCs in a differentiating state, suggesting that a unifying feature of 2q23.1 and 2q33.1 deletion syndrome may be a lack of regulation between proliferation and differentiation in NSCs, as we observed previously for TCF4 and EHMT1 suppression following a similar experimental paradigm. We propose a model of NDDs whereby the balance of NSC proliferation and differentiation is affected, but where the molecules that drive this effect are largely specific to disease-causing genetic variation. NDDs are diverse, complex and unique, but the optimal balance of factors that determine when and where neural stem cells differentiate may be a major feature underlying the diverse phenotypic spectrum of NDDs.
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Affiliation(s)
- C O Gigek
- Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, QC, Canada
| | - E S Chen
- Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, QC, Canada
| | - V K Ota
- Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, QC, Canada
| | - G Maussion
- Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, QC, Canada
| | - H Peng
- Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, QC, Canada
| | - K Vaillancourt
- Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, QC, Canada
| | - A B Diallo
- Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, QC, Canada
| | - J P Lopez
- Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, QC, Canada
| | - L Crapper
- Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, QC, Canada
| | - C Vasuta
- Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, QC, Canada
| | - G G Chen
- Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, QC, Canada
| | - C Ernst
- Department of Psychiatry, McGill Group for Suicide Studies, McGill University, Montreal, QC, Canada,Douglas Hospital Research Institute, 6875 LaSalle Boulevard, Frank Common Building Room 2101.2 Verdun, QC, Canada H4H 1R3. E-mail:
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73
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Ankrd11 is a chromatin regulator involved in autism that is essential for neural development. Dev Cell 2014; 32:31-42. [PMID: 25556659 DOI: 10.1016/j.devcel.2014.11.031] [Citation(s) in RCA: 119] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2014] [Revised: 10/08/2014] [Accepted: 11/20/2014] [Indexed: 02/05/2023]
Abstract
Ankrd11 is a potential chromatin regulator implicated in neural development and autism spectrum disorder (ASD) with no known function in the brain. Here, we show that knockdown of Ankrd11 in developing murine or human cortical neural precursors caused decreased proliferation, reduced neurogenesis, and aberrant neuronal positioning. Similar cellular phenotypes and aberrant ASD-like behaviors were observed in Yoda mice carrying a point mutation in the Ankrd11 HDAC-binding domain. Consistent with a role for Ankrd11 in histone acetylation, Ankrd11 was associated with chromatin and colocalized with HDAC3, and expression and histone acetylation of Ankrd11 target genes were altered in Yoda neural precursors. Moreover, the Ankrd11 knockdown-mediated decrease in precursor proliferation was rescued by inhibiting histone acetyltransferase activity or expressing HDAC3. Thus, Ankrd11 is a crucial chromatin regulator that controls histone acetylation and gene expression during neural development, thereby providing a likely explanation for its association with cognitive dysfunction and ASD.
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