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Järvelä I, Paetau R, Rajendran Y, Acharya A, Bharadwaj T, Leal SM, Lehesjoki AE, Palomäki M, Schrauwen I. Heterogeneous genetic patterns in bilateral perisylvian polymicrogyria: insights from a Finnish family cohort. Brain Commun 2024; 6:fcae142. [PMID: 38712318 PMCID: PMC11073749 DOI: 10.1093/braincomms/fcae142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 02/21/2024] [Accepted: 04/16/2024] [Indexed: 05/08/2024] Open
Abstract
Bilateral perisylvian polymicrogyria is the most common form of regional polymicrogyria within malformations of cortical development, constituting 20% of all malformations of cortical development. Bilateral perisylvian polymicrogyria is characterized by an excessive folding of the cerebral cortex and abnormal cortical layering. Notable clinical features include upper motoneuron dysfunction, dysarthria and asymmetric quadriparesis. Cognitive impairment and epilepsy are frequently observed. To identify genetic variants underlying bilateral perisylvian polymicrogyria in Finland, we examined 21 families using standard exome sequencing, complemented by optical genome mapping and/or deep exome sequencing. Pathogenic or likely pathogenic variants were identified in 5/21 (24%) of families, of which all were confirmed as de novo. These variants were identified in five genes, i.e. DDX23, NUS1, SCN3A, TUBA1A and TUBB2B, with NUS1 and DDX23 being associated with bilateral perisylvian polymicrogyria for the first time. In conclusion, our results confirm the previously reported genetic heterogeneity of bilateral perisylvian polymicrogyria and underscore the necessity of more advanced methods to elucidate the genetic background of bilateral perisylvian polymicrogyria.
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Affiliation(s)
- Irma Järvelä
- Department of Medical Genetics, University of Helsinki, 00251 Helsinki, Finland
| | - Ritva Paetau
- Department of Child Neurology, University of Helsinki and Helsinki University Hospital, 00290 Helsinki, Finland
| | - Yasmin Rajendran
- Center for Statistical Genetics, Gertrude H. Sergievsky Center, Department of Neurology, Columbia University Medical Center, 10032 New York, NY, USA
| | - Anushree Acharya
- Center for Statistical Genetics, Gertrude H. Sergievsky Center, Department of Neurology, Columbia University Medical Center, 10032 New York, NY, USA
| | - Thashi Bharadwaj
- Center for Statistical Genetics, Gertrude H. Sergievsky Center, Department of Neurology, Columbia University Medical Center, 10032 New York, NY, USA
| | - Suzanne M Leal
- Center for Statistical Genetics, Gertrude H. Sergievsky Center, Department of Neurology, Columbia University Medical Center, 10032 New York, NY, USA
- Taub Institute, Columbia University Medical Center, 10032 New York, NY, USA
| | - Anna-Elina Lehesjoki
- Department of Medical Genetics, University of Helsinki, 00251 Helsinki, Finland
- Folkhälsan Research Center, 00290 Helsinki, Finland
| | - Maarit Palomäki
- Medical Imaging Center, University of Helsinki and Helsinki University Hospital, 00290 Helsinki, Finland
| | - Isabelle Schrauwen
- Center for Statistical Genetics, Gertrude H. Sergievsky Center, Department of Neurology, Columbia University Medical Center, 10032 New York, NY, USA
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Abbaali I, Truong D, Day SD, Mushayeed F, Ganesh B, Haro-Ramirez N, Isles J, Nag H, Pham C, Shah P, Tomar I, Manel-Romero C, Morrissette NS. The tubulin database: Linking mutations, modifications, ligands and local interactions. PLoS One 2023; 18:e0295279. [PMID: 38064432 PMCID: PMC10707541 DOI: 10.1371/journal.pone.0295279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Accepted: 11/20/2023] [Indexed: 12/18/2023] Open
Abstract
Microtubules are polymeric filaments, constructed of α-β tubulin heterodimers that underlie critical subcellular structures in eukaryotic organisms. Four homologous proteins (γ-, δ-, ε- and ζ-tubulin) additionally contribute to specialized microtubule functions. Although there is an immense volume of publicly available data pertaining to tubulins, it is difficult to assimilate all potentially relevant information across diverse organisms, isotypes, and categories of data. We previously assembled an extensive web-based catalogue of published missense mutations to tubulins with >1,500 entries that each document a specific substitution to a discrete tubulin, the species where the mutation was described and the associated phenotype with hyperlinks to the amino acid sequence and citation(s) for research. This report describes a significant update and expansion of our online resource (TubulinDB.bio.uci.edu) to nearly 18,000 entries. It now encompasses a cross-referenced catalog of post-translational modifications (PTMs) to tubulin drawn from public datasets, primary literature, and predictive algorithms. In addition, tubulin protein structures were used to define local interactions with bound ligands (GTP, GDP and diverse microtubule-targeting agents) and amino acids at the intradimer interface, within the microtubule lattice and with associated proteins. To effectively cross-reference these datasets, we established a universal tubulin numbering system to map entries into a common framework that accommodates specific insertions and deletions to tubulins. Indexing and cross-referencing permitted us to discern previously unappreciated patterns. We describe previously unlinked observations of loss of PTM sites in the context of cancer cells and tubulinopathies. Similarly, we expanded the set of clinical substitutions that may compromise MAP or microtubule-motor interactions by collecting tubulin missense mutations that alter amino acids at the interface with dynein and doublecortin. By expanding the database as a curated resource, we hope to relate model organism data to clinical findings of pathogenic tubulin variants. Ultimately, we aim to aid researchers in hypothesis generation and design of studies to dissect tubulin function.
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Affiliation(s)
- Izra Abbaali
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, United States of America
| | - Danny Truong
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, United States of America
| | - Shania Deon Day
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, United States of America
| | - Faliha Mushayeed
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, United States of America
| | - Bhargavi Ganesh
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, United States of America
| | - Nancy Haro-Ramirez
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, United States of America
| | - Juliet Isles
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, United States of America
| | - Hindol Nag
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, United States of America
| | - Catherine Pham
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, United States of America
| | - Priya Shah
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, United States of America
| | - Ishaan Tomar
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, United States of America
| | - Carolina Manel-Romero
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, United States of America
| | - Naomi S. Morrissette
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, United States of America
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Akula SK, Chen AY, Neil JE, Shao DD, Mo A, Hylton NK, DiTroia S, Ganesh VS, Smith RS, O’Kane K, Yeh RC, Marciano JH, Kirkham S, Kenny CJ, Song JHT, Al Saffar M, Millan F, Harris DJ, Murphy AV, Klemp KC, Braddock SR, Brand H, Wong I, Talkowski ME, O’Donnell-Luria A, Lai A, Hill RS, Mochida GH, Doan RN, Barkovich AJ, Yang E, Amrom D, Andermann E, Poduri A, Walsh CA. Exome Sequencing and the Identification of New Genes and Shared Mechanisms in Polymicrogyria. JAMA Neurol 2023; 80:980-988. [PMID: 37486637 PMCID: PMC10366952 DOI: 10.1001/jamaneurol.2023.2363] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 03/23/2023] [Indexed: 07/25/2023]
Abstract
Importance Polymicrogyria is the most commonly diagnosed cortical malformation and is associated with neurodevelopmental sequelae including epilepsy, motor abnormalities, and cognitive deficits. Polymicrogyria frequently co-occurs with other brain malformations or as part of syndromic diseases. Past studies of polymicrogyria have defined heterogeneous genetic and nongenetic causes but have explained only a small fraction of cases. Objective To survey germline genetic causes of polymicrogyria in a large cohort and to consider novel polymicrogyria gene associations. Design, Setting, and Participants This genetic association study analyzed panel sequencing and exome sequencing of accrued DNA samples from a retrospective cohort of families with members with polymicrogyria. Samples were accrued over more than 20 years (1994 to 2020), and sequencing occurred in 2 stages: panel sequencing (June 2015 to January 2016) and whole-exome sequencing (September 2019 to March 2020). Individuals seen at multiple clinical sites for neurological complaints found to have polymicrogyria on neuroimaging, then referred to the research team by evaluating clinicians, were included in the study. Targeted next-generation sequencing and/or exome sequencing were performed on probands (and available parents and siblings) from 284 families with individuals who had isolated polymicrogyria or polymicrogyria as part of a clinical syndrome and no genetic diagnosis at time of referral from clinic, with sequencing from 275 families passing quality control. Main Outcomes and Measures The number of families in whom genetic sequencing yielded a molecular diagnosis that explained the polymicrogyria in the family. Secondarily, the relative frequency of different genetic causes of polymicrogyria and whether specific genetic causes were associated with co-occurring head size changes were also analyzed. Results In 32.7% (90 of 275) of polymicrogyria-affected families, genetic variants were identified that provided satisfactory molecular explanations. Known genes most frequently implicated by polymicrogyria-associated variants in this cohort were PIK3R2, TUBB2B, COL4A1, and SCN3A. Six candidate novel polymicrogyria genes were identified or confirmed: de novo missense variants in PANX1, QRICH1, and SCN2A and compound heterozygous variants in TMEM161B, KIF26A, and MAN2C1, each with consistent genotype-phenotype relationships in multiple families. Conclusions and Relevance This study's findings reveal a higher than previously recognized rate of identifiable genetic causes, specifically of channelopathies, in individuals with polymicrogyria and support the utility of exome sequencing for families affected with polymicrogyria.
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Affiliation(s)
- Shyam K. Akula
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children’s Hospital, and Allen Discovery Center for Human Brain Evolution, Boston, Massachusetts
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts
- Harvard-MIT MD/PhD Program, Harvard Medical School, Boston, Massachusetts
| | - Allen Y. Chen
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children’s Hospital, and Allen Discovery Center for Human Brain Evolution, Boston, Massachusetts
- Division of Rheumatology, Hospital for Special Surgery, New York, New York
| | - Jennifer E. Neil
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children’s Hospital, and Allen Discovery Center for Human Brain Evolution, Boston, Massachusetts
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts
| | - Diane D. Shao
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children’s Hospital, and Allen Discovery Center for Human Brain Evolution, Boston, Massachusetts
- Department of Neurology, Boston Children’s Hospital, Boston, Massachusetts
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts
| | - Alisa Mo
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children’s Hospital, and Allen Discovery Center for Human Brain Evolution, Boston, Massachusetts
- Department of Neurology, Boston Children’s Hospital, Boston, Massachusetts
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts
| | - Norma K. Hylton
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children’s Hospital, and Allen Discovery Center for Human Brain Evolution, Boston, Massachusetts
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts
- Harvard-MIT MD/PhD Program, Harvard Medical School, Boston, Massachusetts
| | - Stephanie DiTroia
- Program in Medical and Population Genetics, Center for Genomic Medicine, Stanley Center for Psychiatric Research, The Broad Institute of MIT and Harvard, Cambridge, Massachusetts
| | - Vijay S. Ganesh
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children’s Hospital, and Allen Discovery Center for Human Brain Evolution, Boston, Massachusetts
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts
| | - Richard S. Smith
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Katherine O’Kane
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children’s Hospital, and Allen Discovery Center for Human Brain Evolution, Boston, Massachusetts
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts
| | - Rebecca C. Yeh
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children’s Hospital, and Allen Discovery Center for Human Brain Evolution, Boston, Massachusetts
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts
| | - Jack H. Marciano
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children’s Hospital, and Allen Discovery Center for Human Brain Evolution, Boston, Massachusetts
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts
| | - Samantha Kirkham
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children’s Hospital, and Allen Discovery Center for Human Brain Evolution, Boston, Massachusetts
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts
| | - Connor J. Kenny
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children’s Hospital, and Allen Discovery Center for Human Brain Evolution, Boston, Massachusetts
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts
| | - Janet H. T. Song
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children’s Hospital, and Allen Discovery Center for Human Brain Evolution, Boston, Massachusetts
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts
| | - Muna Al Saffar
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children’s Hospital, and Allen Discovery Center for Human Brain Evolution, Boston, Massachusetts
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts
- Department of Genetics and Genomics, United Arab Emirates University, United Arab Emirates
| | | | - David J. Harris
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children’s Hospital, and Allen Discovery Center for Human Brain Evolution, Boston, Massachusetts
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts
| | - Andrea V. Murphy
- Division of Medical Genetics, Our Lady of the Lake Health System, Baton Rouge, Louisiana
| | - Kara C. Klemp
- Division of Medical Genetics, Department of Pediatrics Saint Louis University School of Medicine, St Louis, Missouri
| | - Stephen R. Braddock
- Division of Medical Genetics, Department of Pediatrics Saint Louis University School of Medicine, St Louis, Missouri
| | - Harrison Brand
- Program in Medical and Population Genetics, Center for Genomic Medicine, Stanley Center for Psychiatric Research, The Broad Institute of MIT and Harvard, Cambridge, Massachusetts
- Department of Neurology, Harvard Medical School, Boston, Massachusetts
| | - Isaac Wong
- Program in Medical and Population Genetics, Center for Genomic Medicine, Stanley Center for Psychiatric Research, The Broad Institute of MIT and Harvard, Cambridge, Massachusetts
- Department of Neurology, Harvard Medical School, Boston, Massachusetts
| | - Michael E. Talkowski
- Program in Medical and Population Genetics, Center for Genomic Medicine, Stanley Center for Psychiatric Research, The Broad Institute of MIT and Harvard, Cambridge, Massachusetts
- Department of Neurology, Harvard Medical School, Boston, Massachusetts
| | - Anne O’Donnell-Luria
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children’s Hospital, and Allen Discovery Center for Human Brain Evolution, Boston, Massachusetts
- Program in Medical and Population Genetics, Center for Genomic Medicine, Stanley Center for Psychiatric Research, The Broad Institute of MIT and Harvard, Cambridge, Massachusetts
| | - Abbe Lai
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children’s Hospital, and Allen Discovery Center for Human Brain Evolution, Boston, Massachusetts
- Department of Neurology, Boston Children’s Hospital, Boston, Massachusetts
| | - Robert Sean Hill
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children’s Hospital, and Allen Discovery Center for Human Brain Evolution, Boston, Massachusetts
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts
| | - Ganeshwaran H. Mochida
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children’s Hospital, and Allen Discovery Center for Human Brain Evolution, Boston, Massachusetts
- Department of Neurology, Boston Children’s Hospital, Boston, Massachusetts
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts
| | - Ryan N. Doan
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children’s Hospital, and Allen Discovery Center for Human Brain Evolution, Boston, Massachusetts
| | - A. James Barkovich
- Benioff Children’s Hospital, Departments of Radiology, Pediatrics, Neurology, and Neurological Surgery, University of California, San Francisco, San Francisco
| | - Edward Yang
- Department of Radiology, Boston Children’s Hospital, Boston, Massachusetts
| | - Dina Amrom
- Neurogenetics Unit, Montreal Neurological Hospital and Institute, Montreal, Quebec, Canada
- Department of Neurology & Neurosurgery, McGill University, Montreal, Quebec, Canada
- Department of Neurology, Queen Fabiola Children’s University Hospital, Brussels, Belgium
- Pediatric Neurology Unit, Centre Hospitalier de Luxembourg, Grand-Duchy of Luxembourg
| | - Eva Andermann
- Department of Neurology & Neurosurgery, McGill University, Montreal, Quebec, Canada
- Pediatric Neurology Unit, Centre Hospitalier de Luxembourg, Grand-Duchy of Luxembourg
- Epilepsy Research Group, Montreal Neurological Hospital and Institute, Quebec, Canada
- Department of Human Genetics, McGill University, Montreal, Quebec, Canada
| | - Annapurna Poduri
- Department of Neurology, Boston Children’s Hospital, Boston, Massachusetts
| | - Christopher A. Walsh
- Division of Genetics and Genomics, Department of Pediatrics, Boston Children’s Hospital, and Allen Discovery Center for Human Brain Evolution, Boston, Massachusetts
- Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, Massachusetts
- Harvard-MIT MD/PhD Program, Harvard Medical School, Boston, Massachusetts
- Program in Medical and Population Genetics, Center for Genomic Medicine, Stanley Center for Psychiatric Research, The Broad Institute of MIT and Harvard, Cambridge, Massachusetts
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Zhang L, Tie X, Che F, Wang G, Ge Y, Li B, Yang Y. Novel maternal duplication of 6p22.3-p25.3 with subtelomeric 6p25.3 deletion: new clinical findings and genotype-phenotype correlations. Mol Cytogenet 2023; 16:11. [PMID: 37303060 DOI: 10.1186/s13039-023-00640-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Accepted: 05/24/2023] [Indexed: 06/13/2023] Open
Abstract
BACKGROUND Copy-number variants (CNVs) drive many neurodevelopmental-related disorders. Although many neurodevelopmental-related CNVs can give rise to widespread phenotypes, it is necessary to identify the major genes contributing to phenotypic presentation. Copy-number variations in chromosome 6, such as independent 6p deletion and 6p duplication, have been reported in several live-born infants and present widespread abnormalities such as intellectual disability, growth deficiency, developmental delay, and multiple dysmorphic facial features. However, a contiguous deletion and duplication in chromosome 6p regions have been reported in only a few cases. CASE PRESENTATION In this study, we reported the first duplication of chromosome band 6p25.3-p22.3 with deletion of 6p25.3 in a pedigree. This is the first case reported involving CNVs in these chromosomal regions. In this pedigree, we reported a 1-year-old boy with maternal 6p25-pter duplication characterized by chromosome karyotype. Further analysis using CNV-seq revealed a 20.88-Mb duplication at 6p25.3-p22.3 associated with a contiguous 0.66-Mb 6p25.3 deletion. Whole exome sequencing confirmed the deletion/duplication and identified no pathogenic or likely pathogenic variants related with the patient´s phenotype. The proband presented abnormal growth, developmental delay, skeletal dysplasia, hearing loss, and dysmorphic facial features. Additionally, he presented recurrent infection after birth. CNV-seq using the proband´s parental samples showed that the deletion/duplication was inherited from the proband´s mother, who exhibited a similar phenotype to the proband. When compared with other cases, this proband and his mother presented a new clinical finding: forearm bone dysplasia. The major candidate genes contributing to recurrent infection, eye development, hearing loss features, neurodevelopmental development, and congenital bone dysplasia were further discussed. CONCLUSIONS Our results showed a new clinical finding of a contiguous deletion and duplication in chromosome 6p regions and suggested candidate genes associated with phenotypic features, such as FOXC1, SERPINB6, NRN1, TUBB2A, IRF4, and RIPK1.
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Affiliation(s)
- Liyu Zhang
- Shaanxi Institute for Pediatric Diseases, Xi'an Children's Hospital, Xi'an, China
| | - Xiaoling Tie
- Department of Rehabilitation, Xi'an Children's Hospital, Xi'an, China
| | - Fengyu Che
- Shaanxi Institute for Pediatric Diseases, Xi'an Children's Hospital, Xi'an, China
| | - Guoxia Wang
- Shaanxi Institute for Pediatric Diseases, Xi'an Children's Hospital, Xi'an, China
| | - Ying Ge
- The Center Laboratory Medicine, Xi'an Children's Hospital, Xi'an, China
| | - Benchang Li
- Shaanxi Institute for Pediatric Diseases, Xi'an Children's Hospital, Xi'an, China
| | - Ying Yang
- Shaanxi Institute for Pediatric Diseases, Xi'an Children's Hospital, Xi'an, China.
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Tantry MSA, Santhakumar K. Insights on the Role of α- and β-Tubulin Isotypes in Early Brain Development. Mol Neurobiol 2023; 60:3803-3823. [PMID: 36943622 DOI: 10.1007/s12035-023-03302-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 03/05/2023] [Indexed: 03/23/2023]
Abstract
Tubulins are the highly conserved subunit of microtubules which involve in various fundamental functions including brain development. Microtubules help in neuronal proliferation, migration, differentiation, cargo transport along the axons, synapse formation, and many more. Tubulin gene family consisting of multiple isotypes, their differential expression and varied post translational modifications create a whole new level of complexity and diversity in accomplishing manifold neuronal functions. The studies on the relation between tubulin genes and brain development opened a new avenue to understand the role of each tubulin isotype in neurodevelopment. Mutations in tubulin genes are reported to cause brain development defects especially cortical malformations, referred as tubulinopathies. There is an increased need to understand the molecular correlation between various tubulin mutations and the associated brain pathology. Recently, mutations in tubulin isotypes (TUBA1A, TUBB, TUBB1, TUBB2A, TUBB2B, TUBB3, and TUBG1) have been linked to cause various neurodevelopmental defects like lissencephaly, microcephaly, cortical dysplasia, polymicrogyria, schizencephaly, subcortical band heterotopia, periventricular heterotopia, corpus callosum agenesis, and cerebellar hypoplasia. This review summarizes on the microtubule dynamics, their role in neurodevelopment, tubulin isotypes, post translational modifications, and the role of tubulin mutations in causing specific neurodevelopmental defects. A comprehensive list containing all the reported tubulin pathogenic variants associated with brain developmental defects has been prepared to give a bird's eye view on the broad range of tubulin functions.
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Affiliation(s)
- M S Ananthakrishna Tantry
- Department of Genetic Engineering, SRM Institute of Science and Technology, Kattankulathur, 603203, India
| | - Kirankumar Santhakumar
- Department of Genetic Engineering, SRM Institute of Science and Technology, Kattankulathur, 603203, India.
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Zocchi R, Compagnucci C, Bertini E, Sferra A. Deciphering the Tubulin Language: Molecular Determinants and Readout Mechanisms of the Tubulin Code in Neurons. Int J Mol Sci 2023; 24:ijms24032781. [PMID: 36769099 PMCID: PMC9917122 DOI: 10.3390/ijms24032781] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Revised: 01/17/2023] [Accepted: 01/27/2023] [Indexed: 02/04/2023] Open
Abstract
Microtubules (MTs) are dynamic components of the cell cytoskeleton involved in several cellular functions, such as structural support, migration and intracellular trafficking. Despite their high similarity, MTs have functional heterogeneity that is generated by the incorporation into the MT lattice of different tubulin gene products and by their post-translational modifications (PTMs). Such regulations, besides modulating the tubulin composition of MTs, create on their surface a "biochemical code" that is translated, through the action of protein effectors, into specific MT-based functions. This code, known as "tubulin code", plays an important role in neuronal cells, whose highly specialized morphologies and activities depend on the correct functioning of the MT cytoskeleton and on its interplay with a myriad of MT-interacting proteins. In recent years, a growing number of mutations in genes encoding for tubulins, MT-interacting proteins and enzymes that post-translationally modify MTs, which are the main players of the tubulin code, have been linked to neurodegenerative processes or abnormalities in neural migration, differentiation and connectivity. Nevertheless, the exact molecular mechanisms through which the cell writes and, downstream, MT-interacting proteins decipher the tubulin code are still largely uncharted. The purpose of this review is to describe the molecular determinants and the readout mechanisms of the tubulin code, and briefly elucidate how they coordinate MT behavior during critical neuronal events, such as neuron migration, maturation and axonal transport.
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Affiliation(s)
- Riccardo Zocchi
- Unit of Neuromuscular Disorders, Translational Pediatrics and Clinical Genetics, Bambino Gesù Children’s Hospital, IRCCS, 00146 Rome, Italy
| | - Claudia Compagnucci
- Molecular Genetics and Functional Genomics, Bambino Gesù Children’s Research Hospital, IRCCS, 00146 Rome, Italy
| | - Enrico Bertini
- Unit of Neuromuscular Disorders, Translational Pediatrics and Clinical Genetics, Bambino Gesù Children’s Hospital, IRCCS, 00146 Rome, Italy
- Correspondence: (E.B.); or (A.S.); Tel.: +39-06-6859-2104 (E.B. & A.S.)
| | - Antonella Sferra
- Unit of Neuromuscular Disorders, Translational Pediatrics and Clinical Genetics, Bambino Gesù Children’s Hospital, IRCCS, 00146 Rome, Italy
- Correspondence: (E.B.); or (A.S.); Tel.: +39-06-6859-2104 (E.B. & A.S.)
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Damianidou E, Mouratidou L, Kyrousi C. Research models of neurodevelopmental disorders: The right model in the right place. Front Neurosci 2022; 16:1031075. [PMID: 36340790 PMCID: PMC9630472 DOI: 10.3389/fnins.2022.1031075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 10/07/2022] [Indexed: 11/25/2022] Open
Abstract
Neurodevelopmental disorders (NDDs) are a heterogeneous group of impairments that affect the development of the central nervous system leading to abnormal brain function. NDDs affect a great percentage of the population worldwide, imposing a high societal and economic burden and thus, interest in this field has widely grown in recent years. Nevertheless, the complexity of human brain development and function as well as the limitations regarding human tissue usage make their modeling challenging. Animal models play a central role in the investigation of the implicated molecular and cellular mechanisms, however many of them display key differences regarding human phenotype and in many cases, they partially or completely fail to recapitulate them. Although in vitro two-dimensional (2D) human-specific models have been highly used to address some of these limitations, they lack crucial features such as complexity and heterogeneity. In this review, we will discuss the advantages, limitations and future applications of in vivo and in vitro models that are used today to model NDDs. Additionally, we will describe the recent development of 3-dimensional brain (3D) organoids which offer a promising approach as human-specific in vitro models to decipher these complex disorders.
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Affiliation(s)
- Eleni Damianidou
- University Mental Health, Neurosciences and Precision Medicine Research Institute “Costas Stefanis”, Athens, Greece
| | - Lidia Mouratidou
- University Mental Health, Neurosciences and Precision Medicine Research Institute “Costas Stefanis”, Athens, Greece
- First Department of Psychiatry, Medical School, Eginition Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Christina Kyrousi
- University Mental Health, Neurosciences and Precision Medicine Research Institute “Costas Stefanis”, Athens, Greece
- First Department of Psychiatry, Medical School, Eginition Hospital, National and Kapodistrian University of Athens, Athens, Greece
- *Correspondence: Christina Kyrousi,
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Attard TJ, Welburn JPI, Marsh JA. Understanding molecular mechanisms and predicting phenotypic effects of pathogenic tubulin mutations. PLoS Comput Biol 2022; 18:e1010611. [PMID: 36206299 PMCID: PMC9581425 DOI: 10.1371/journal.pcbi.1010611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Revised: 10/19/2022] [Accepted: 09/28/2022] [Indexed: 11/21/2022] Open
Abstract
Cells rely heavily on microtubules for several processes, including cell division and molecular trafficking. Mutations in the different tubulin-α and -β proteins that comprise microtubules have been associated with various diseases and are often dominant, sporadic and congenital. While the earliest reported tubulin mutations affect neurodevelopment, mutations are also associated with other disorders such as bleeding disorders and infertility. We performed a systematic survey of tubulin mutations across all isotypes in order to improve our understanding of how they cause disease, and increase our ability to predict their phenotypic effects. Both protein structural analyses and computational variant effect predictors were very limited in their utility for differentiating between pathogenic and benign mutations. This was even worse for those genes associated with non-neurodevelopmental disorders. We selected tubulin-α and -β disease mutations that were most poorly predicted for experimental characterisation. These mutants co-localise to the mitotic spindle in HeLa cells, suggesting they may exert dominant-negative effects by altering microtubule properties. Our results show that tubulin mutations represent a blind spot for current computational approaches, being much more poorly predicted than mutations in most human disease genes. We suggest that this is likely due to their strong association with dominant-negative and gain-of-function mechanisms.
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Affiliation(s)
- Thomas J. Attard
- Wellcome Trust Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, Scotland, United Kingdom
| | - Julie P. I. Welburn
- Wellcome Trust Centre for Cell Biology, School of Biological Sciences, University of Edinburgh, Edinburgh, Scotland, United Kingdom
| | - Joseph A. Marsh
- MRC Human Genetics Unit, Institute of Genetics & Cancer, University of Edinburgh, Edinburgh, United Kingdom
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9
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Maillard C, Roux CJ, Charbit-Henrion F, Steffann J, Laquerriere A, Quazza F, Buisson NB. Tubulin mutations in human neurodevelopmental disorders. Semin Cell Dev Biol 2022; 137:87-95. [PMID: 35915025 DOI: 10.1016/j.semcdb.2022.07.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 07/22/2022] [Accepted: 07/22/2022] [Indexed: 10/16/2022]
Abstract
Mutations causing dysfunction of tubulins and microtubule-associated proteins, also known as tubulinopathies, are a group of recently described entities that lead to complex brain malformations. Anatomical and functional consequences of the disruption of tubulins include microcephaly, combined with abnormal corticogenesis due to impaired migration or lamination and abnormal growth cone dynamics of projecting and callosal axons. Key imaging features of tubulinopathies are characterized by three major patterns of malformations of cortical development (MCD): lissencephaly, microlissencephaly, and dysgyria. Additional distinctive MRI features include dysmorphism of the basal ganglia, midline commissural structure hypoplasia or agenesis, and cerebellar and brainstem hypoplasia. Tubulinopathies can be diagnosed as early as 21-24 gestational weeks using imaging and neuropathology, with possible extreme microlissencephaly with an extremely thin cortex, lissencephaly with either thick or thin/intermediate cortex, and dysgyria combined with cerebellar hypoplasia, pons hypoplasia and corpus callosum dysgenesis. More than 100 MCD-associated mutations have been reported in TUBA1A, TUBB2B, or TUBB3 genes, whereas fewer than ten are known in other genes such TUBB2A, TUBB or TUBG1. Although these mutations are scattered along the α- and β-tubulin sequences, recurrent mutations are consistently associated with almost identical cortical dysgenesis. Much of the evidence supports that these mutations alter the dynamic properties and functions of microtubules in several fashions. These include diminishing the abundance of functional tubulin heterodimers, altering GTP binding, altering longitudinal and lateral protofilament interactions, and impairing microtubule interactions with kinesin and/or dynein motors or with MAPs. In this review we discuss the recent advances in our understanding of the effects of mutations of tubulins and microtubule-associated proteins on human brain development and the pathogenesis of malformations of cortical development.
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Affiliation(s)
- Camille Maillard
- Université de Paris, Imagine Institute, Team Genetics and Development of the Cerebral Cortex, F-75015 Paris, France; Université de Paris, Institute of Psychiatry and Neuroscience of Paris, INSERM U1266, F-75014 Paris, France
| | - Charles Joris Roux
- Pediatric Radiology, Necker Enfants Malades University Hospital, Université de Paris, Paris, France
| | - Fabienne Charbit-Henrion
- Université de Paris, Sorbonne Paris Cité, Imagine INSERM UMR1163, Service de Génétique Moléculaire, Groupe hospitalier Necker-Enfants Malades, AP-HP, France
| | - Julie Steffann
- Université de Paris, Sorbonne Paris Cité, Imagine INSERM UMR1163, Service de Génétique Moléculaire, Groupe hospitalier Necker-Enfants Malades, AP-HP, France
| | - Annie Laquerriere
- Pathology Laboratory, Rouen University Hospital, Rouen, France; NeoVasc Region-Inserm Team ERI28, Laboratory of Microvascular Endothelium and Neonate Brain Lesions, Institute of Research for Innovation in Biomedicine, University of Rouen, Rouen, France
| | - Floriane Quazza
- Pediatric Neurology, Necker Enfants Malades University Hospital, Université de Paris, Paris, France
| | - Nadia Bahi Buisson
- Université de Paris, Imagine Institute, Team Genetics and Development of the Cerebral Cortex, F-75015 Paris, France; Université de Paris, Institute of Psychiatry and Neuroscience of Paris, INSERM U1266, F-75014 Paris, France; Pediatric Neurology, Necker Enfants Malades University Hospital, Université de Paris, Paris, France.
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10
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Dekker J, Diderich KEM, Schot R, Husen SC, Dremmen MHG, Go ATJI, Weerts MJA, van Slegtenhorst MA, Mancini GMS. A novel family illustrating the mild phenotypic spectrum of TUBB2B variants. Eur J Paediatr Neurol 2021; 35:35-39. [PMID: 34592644 DOI: 10.1016/j.ejpn.2021.09.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 08/12/2021] [Accepted: 09/09/2021] [Indexed: 10/20/2022]
Abstract
TUBB2B codes for one of the isotypes of β-tubulin and dominant negative variants in this gene result in distinctive malformations of cortical development (MCD), including dysgyria, dysmorphic basal ganglia and cerebellar anomalies. We present a novel family with a heterozygous missense variant in TUBB2B and an unusually mild phenotype. First, at 21 37 weeks of gestation ultrasonography revealed a fetus with a relatively small head, enlarged lateral ventricles, borderline hypoplastic cerebellum and a thin corpus callosum. The couple opted for pregnancy termination. Exome sequencing on fetal material afterwards identified a heterozygous maternally inherited variant in TUBB2B (NM_178012.4 (TUBB2B):c.530A > T, p.(Asp177Val)), not present in GnomAD and predicted as damaging. The healthy mother had only a language delay in childhood. This inherited TUBB2B variant prompted re-evaluation of the older son of the couple, who presented with a mild delay in motor skills and speech. His MRI revealed mildly enlarged lateral ventricles, a thin corpus callosum, mild cortical dysgyria, and dysmorphic vermis and basal ganglia, a pattern typical of tubulinopathies. This son finally showed the same TUBB2B variant, supporting pathogenicity of the TUBB2B variant. These observations illustrate the wide phenotypic heterogeneity of tubulinopathies, including reduced penetrance and mild expressivity, that require careful evaluation in pre- and postnatal counseling.
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Affiliation(s)
- Jordy Dekker
- Department of Clinical Genetics, Erasmus MC University Medical Center, 3015, GD Rotterdam, the Netherlands
| | - Karin E M Diderich
- Department of Clinical Genetics, Erasmus MC University Medical Center, 3015, GD Rotterdam, the Netherlands
| | - Rachel Schot
- Department of Clinical Genetics, Erasmus MC University Medical Center, 3015, GD Rotterdam, the Netherlands
| | - Sofie C Husen
- Department of Obstetrics and Prenatal Medicine, Erasmus MC University Medical Center, 3015, GD Rotterdam, the Netherlands
| | - Marjolein H G Dremmen
- Department of Radiology and Nuclear Medicine, Erasmus MC University Medical Center, 3015, GD Rotterdam, the Netherlands
| | - Attie T J I Go
- Department of Obstetrics and Prenatal Medicine, Erasmus MC University Medical Center, 3015, GD Rotterdam, the Netherlands
| | - Marjolein J A Weerts
- Department of Clinical Genetics, Erasmus MC University Medical Center, 3015, GD Rotterdam, the Netherlands
| | - Marjon A van Slegtenhorst
- Department of Clinical Genetics, Erasmus MC University Medical Center, 3015, GD Rotterdam, the Netherlands
| | - Grazia M S Mancini
- Department of Clinical Genetics, Erasmus MC University Medical Center, 3015, GD Rotterdam, the Netherlands.
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11
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Abstract
Abnormalities in cranial motor nerve development cause paralytic strabismus syndromes, collectively referred to as congenital cranial dysinnervation disorders, in which patients cannot fully move their eyes. These disorders can arise through one of two mechanisms: (a) defective motor neuron specification, usually by loss of a transcription factor necessary for brainstem patterning, or (b) axon growth and guidance abnormalities of the oculomotor, trochlear, and abducens nerves. This review focuses on our current understanding of axon guidance mechanisms in the cranial motor nerves and how disease-causing mutations disrupt axon targeting. Abnormalities of axon growth and guidance are often limited to a single nerve or subdivision, even when the causative gene is ubiquitously expressed. Additionally, when one nerve is absent, its normal target muscles attract other motor neurons. Study of these disorders highlights the complexities of axon guidance and how each population of neurons uses a unique but overlapping set of axon guidance pathways. Expected final online publication date for the Annual Review of Vision Science, Volume 7 is September 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Mary C Whitman
- Department of Ophthalmology, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA;
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12
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Morandell J, Schwarz LA, Basilico B, Tasciyan S, Dimchev G, Nicolas A, Sommer C, Kreuzinger C, Dotter CP, Knaus LS, Dobler Z, Cacci E, Schur FKM, Danzl JG, Novarino G. Cul3 regulates cytoskeleton protein homeostasis and cell migration during a critical window of brain development. Nat Commun 2021; 12:3058. [PMID: 34031387 PMCID: PMC8144225 DOI: 10.1038/s41467-021-23123-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 04/14/2021] [Indexed: 01/03/2023] Open
Abstract
De novo loss of function mutations in the ubiquitin ligase-encoding gene Cullin3 (CUL3) lead to autism spectrum disorder (ASD). In mouse, constitutive Cul3 haploinsufficiency leads to motor coordination deficits as well as ASD-relevant social and cognitive impairments. However, induction of Cul3 haploinsufficiency later in life does not lead to ASD-relevant behaviors, pointing to an important role of Cul3 during a critical developmental window. Here we show that Cul3 is essential to regulate neuronal migration and, therefore, constitutive Cul3 heterozygous mutant mice display cortical lamination abnormalities. At the molecular level, we found that Cul3 controls neuronal migration by tightly regulating the amount of Plastin3 (Pls3), a previously unrecognized player of neural migration. Furthermore, we found that Pls3 cell-autonomously regulates cell migration by regulating actin cytoskeleton organization, and its levels are inversely proportional to neural migration speed. Finally, we provide evidence that cellular phenotypes associated with autism-linked gene haploinsufficiency can be rescued by transcriptional activation of the intact allele in vitro, offering a proof of concept for a potential therapeutic approach for ASDs. De novo loss of function mutations in the ubiquitin ligase-encoding gene Cullin3 (CUL3) lead to autism spectrum disorder (ASD). Here, the authors show that Cul3 is essential to regulate neuronal migration by tightly regulating Plastin3 (Pls3). Pls3 cell-autonomously regulates cell migration by regulating the actin cytoskeleton organization.
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Affiliation(s)
- Jasmin Morandell
- Institute of Science and Technology (IST) Austria, Klosterneuburg, Austria
| | - Lena A Schwarz
- Institute of Science and Technology (IST) Austria, Klosterneuburg, Austria
| | | | - Saren Tasciyan
- Institute of Science and Technology (IST) Austria, Klosterneuburg, Austria
| | - Georgi Dimchev
- Institute of Science and Technology (IST) Austria, Klosterneuburg, Austria
| | - Armel Nicolas
- Institute of Science and Technology (IST) Austria, Klosterneuburg, Austria
| | - Christoph Sommer
- Institute of Science and Technology (IST) Austria, Klosterneuburg, Austria
| | | | - Christoph P Dotter
- Institute of Science and Technology (IST) Austria, Klosterneuburg, Austria
| | - Lisa S Knaus
- Institute of Science and Technology (IST) Austria, Klosterneuburg, Austria
| | - Zoe Dobler
- Institute of Science and Technology (IST) Austria, Klosterneuburg, Austria
| | - Emanuele Cacci
- Department of Biology and Biotechnology "Charles Darwin", Sapienza, University of Rome, Rome, Italy
| | - Florian K M Schur
- Institute of Science and Technology (IST) Austria, Klosterneuburg, Austria
| | - Johann G Danzl
- Institute of Science and Technology (IST) Austria, Klosterneuburg, Austria
| | - Gaia Novarino
- Institute of Science and Technology (IST) Austria, Klosterneuburg, Austria.
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13
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Fourel G, Boscheron C. Tubulin mutations in neurodevelopmental disorders as a tool to decipher microtubule function. FEBS Lett 2020; 594:3409-3438. [PMID: 33064843 DOI: 10.1002/1873-3468.13958] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 09/28/2020] [Accepted: 10/05/2020] [Indexed: 01/08/2023]
Abstract
Malformations of cortical development (MCDs) are a group of severe brain malformations associated with intellectual disability and refractory childhood epilepsy. Human missense heterozygous mutations in the 9 α-tubulin and 10 β-tubulin isoforms forming the heterodimers that assemble into microtubules (MTs) were found to cause MCDs. However, how a single mutated residue in a given tubulin isoform can perturb the entire microtubule population in a neuronal cell remains a crucial question. Here, we examined 85 MCD-associated tubulin mutations occurring in TUBA1A, TUBB2, and TUBB3 and their location in a three-dimensional (3D) microtubule cylinder. Mutations hitting residues exposed on the outer microtubule surface are likely to alter microtubule association with partners, while alteration of intradimer contacts may impair dimer stability and straightness. Other types of mutations are predicted to alter interdimer and lateral contacts, which are responsible for microtubule cohesion, rigidity, and dynamics. MCD-associated tubulin mutations surprisingly fall into all categories, thus providing unexpected insights into how a single mutation may impair microtubule function and elicit dominant effects in neurons.
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14
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Microtubule Dysfunction: A Common Feature of Neurodegenerative Diseases. Int J Mol Sci 2020; 21:ijms21197354. [PMID: 33027950 PMCID: PMC7582320 DOI: 10.3390/ijms21197354] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 09/24/2020] [Accepted: 10/01/2020] [Indexed: 12/13/2022] Open
Abstract
Neurons are particularly susceptible to microtubule (MT) defects and deregulation of the MT cytoskeleton is considered to be a common insult during the pathogenesis of neurodegenerative disorders. Evidence that dysfunctions in the MT system have a direct role in neurodegeneration comes from findings that several forms of neurodegenerative diseases are associated with changes in genes encoding tubulins, the structural units of MTs, MT-associated proteins (MAPs), or additional factors such as MT modifying enzymes which modulating tubulin post-translational modifications (PTMs) regulate MT functions and dynamics. Efforts to use MT-targeting therapeutic agents for the treatment of neurodegenerative diseases are underway. Many of these agents have provided several benefits when tested on both in vitro and in vivo neurodegenerative model systems. Currently, the most frequently addressed therapeutic interventions include drugs that modulate MT stability or that target tubulin PTMs, such as tubulin acetylation. The purpose of this review is to provide an update on the relevance of MT dysfunctions to the process of neurodegeneration and briefly discuss advances in the use of MT-targeting drugs for the treatment of neurodegenerative disorders.
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15
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Associated analysis of PER1/TUBB2B with endometrial cancer development caused by circadian rhythm disorders. Med Oncol 2020; 37:90. [DOI: 10.1007/s12032-020-01415-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 08/30/2020] [Indexed: 10/23/2022]
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16
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Bittermann E, Abdelhamed Z, Liegel RP, Menke C, Timms A, Beier DR, Stottmann RW. Differential requirements of tubulin genes in mammalian forebrain development. PLoS Genet 2019; 15:e1008243. [PMID: 31386652 PMCID: PMC6697361 DOI: 10.1371/journal.pgen.1008243] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 08/16/2019] [Accepted: 06/12/2019] [Indexed: 11/24/2022] Open
Abstract
Tubulin genes encode a series of homologous proteins used to construct microtubules which are essential for multiple cellular processes. Neural development is particularly reliant on functional microtubule structures. Tubulin genes comprise a large family of genes with very high sequence similarity between multiple family members. Human genetics has demonstrated that a large spectrum of cortical malformations are associated with de novo heterozygous mutations in tubulin genes. However, the absolute requirement for many of these genes in development and disease has not been previously tested in genetic loss of function models. Here we directly test the requirement for Tuba1a, Tubb2a and Tubb2b in the mouse by deleting each gene individually using CRISPR-Cas9 genome editing. We show that loss of Tubb2a or Tubb2b does not impair survival but does lead to relatively mild cortical malformation phenotypes. In contrast, loss of Tuba1a is perinatal lethal and leads to significant forebrain dysmorphology. We also present a novel mouse ENU allele of Tuba1a with phenotypes similar to the null allele. This demonstrates the requirements for each of the tubulin genes and levels of functional redundancy are quite different throughout the gene family. The ability of the mouse to survive in the absence of some tubulin genes known to cause disease in humans suggests future intervention strategies for these devastating tubulinopathy diseases.
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Affiliation(s)
- Elizabeth Bittermann
- Division of Human Genetics, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
| | - Zakia Abdelhamed
- Division of Human Genetics, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
- Department of Anatomy and Embryology, Faculty of Medicine (Girl’s Section), Al-Azhar University, Cairo, Egypt
| | - Ryan P. Liegel
- Division of Human Genetics, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
| | - Chelsea Menke
- Division of Human Genetics, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
| | - Andrew Timms
- Center for Developmental Biology and Regenerative Medicine, Seattle Children’s Research Institute, Seattle, Washington, United States of America
| | - David R. Beier
- Center for Developmental Biology and Regenerative Medicine, Seattle Children’s Research Institute, Seattle, Washington, United States of America
- Department of Pediatrics, University of Washington Medical School, Seattle, Washington, United States of America
| | - Rolf W. Stottmann
- Division of Human Genetics, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
- Division of Developmental Biology, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
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17
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Epilepsy in Tubulinopathy: Personal Series and Literature Review. Cells 2019; 8:cells8070669. [PMID: 31269740 PMCID: PMC6678821 DOI: 10.3390/cells8070669] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 06/25/2019] [Accepted: 06/28/2019] [Indexed: 11/17/2022] Open
Abstract
Mutations in tubulin genes are responsible for a large spectrum of brain malformations secondary to abnormal neuronal migration, organization, differentiation and axon guidance and maintenance. Motor impairment, intellectual disability and epilepsy are the main clinical symptoms. In the present study 15 patients from a personal cohort and 75 from 21 published studies carrying mutations in TUBA1A, TUBB2B and TUBB3 tubulin genes were evaluated with the aim to define a clinical and electrophysiological associated pattern. Epilepsy shows a wide range of severity without a specific pattern. Mutations in TUBA1A (60%) and TUBB2B (74%) and TUBB3 (25%) genes are associated with epilepsy. The accurate analysis of the Electroencephalogram (EEG) pattern in wakefulness and sleep in our series allows us to detect significant abnormalities of the background activity in 100% of patients. The involvement of white matter and of the inter-hemispheric connection structures typically observed in tubulinopathies is evidenced by the high percentage of asynchronisms in the organization of sleep activity recorded. In addition to asymmetries of the background activity, excess of slowing, low amplitude and Magnetic Resonance (MR) imaging confirm the presence of extensive brain malformations involving subcortical and midline structures. In conclusion, epilepsy in tubulinopathies when present has a favorable evolution over time suggesting a not particularly aggressive therapeutic approach.
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18
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Shao Q, Yang T, Huang H, Majumder T, Khot BA, Khouzani MM, Alarmanazi F, Gore YK, Liu G. Disease-associated mutations in human TUBB3 disturb netrin repulsive signaling. PLoS One 2019; 14:e0218811. [PMID: 31226147 PMCID: PMC6588280 DOI: 10.1371/journal.pone.0218811] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 06/10/2019] [Indexed: 11/28/2022] Open
Abstract
Missense mutations in the human TUBB3 gene cause a variety of neurological disorders associated with defects in axon guidance and neuronal migration, but the underlying molecular mechanisms are not well understood. Recent studies have shown that direct coupling of dynamic TUBB3 in microtubules with netrin receptors is required for netrin-1-mediated axon guidance, and the interaction of netrin-1 repulsive receptor UNC5C with TUBB3 is involved in netrin-1 mediated axonal repulsion. Here, we report that TUBB3 mutations perturb netrin-1/UNC5C repulsive signaling in the developing nervous system. Among twelve mutants reported in previous studies, five of them show significantly reduced interaction with UNC5C in comparison to the wild-type TUBB3. TUBB3 mutants R262C and R62Q exhibit decreased subcellular colocalization with UNC5C in the peripheral area of the growth cone of primary mouse neurons. Netrin-1 reduces the colocalization of UNC5C with wild-type TUBB3, but not TUBB3 mutants R262C or R62Q, in the growth cone. Results from the in vitro cosedimentation assay indicate that netrin-1 inhibits cosedimentation of UNC5C with polymerized microtubules in primary mouse neurons expressing the wild-type TUBB3, but not R262C or R62Q. Expression of either R262C or R62Q not only blocks netrin-1-induced growth cone collapse and axonal repulsion of primary EGL cells in vitro, but also results in axon projections defects of chicken dorsal root ganglion neurons in ovo. Our study reveals that human TUBB3 mutations specifically perturb netrin-1/UNC5C-mediated repulsion.
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Affiliation(s)
- Qiangqiang Shao
- Department of Biological Sciences, University of Toledo, Toledo, OH, United States of America
| | - Tao Yang
- Department of Biological Sciences, University of Toledo, Toledo, OH, United States of America
| | - Huai Huang
- Department of Biological Sciences, University of Toledo, Toledo, OH, United States of America
| | - Tanushree Majumder
- Department of Biological Sciences, University of Toledo, Toledo, OH, United States of America
| | - Bhakti Ajit Khot
- Department of Biological Sciences, University of Toledo, Toledo, OH, United States of America
| | | | - Farrah Alarmanazi
- Department of Biological Sciences, University of Toledo, Toledo, OH, United States of America
| | - Yasmin K. Gore
- Department of Biological Sciences, University of Toledo, Toledo, OH, United States of America
| | - Guofa Liu
- Department of Biological Sciences, University of Toledo, Toledo, OH, United States of America
- * E-mail:
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19
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Guarnieri FC, de Chevigny A, Falace A, Cardoso C. Disorders of neurogenesis and cortical development. DIALOGUES IN CLINICAL NEUROSCIENCE 2019. [PMID: 30936766 PMCID: PMC6436956 DOI: 10.31887/dcns.2018.20.4/ccardoso] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The development of the cerebral cortex requires complex sequential processes that have to be precisely orchestrated. The localization and timing of neuronal progenitor proliferation and of neuronal migration define the identity, laminar positioning, and specific connectivity of each single cortical neuron. Alterations at any step of this organized series of events—due to genetic mutations or environmental factors—lead to defined brain pathologies collectively known as malformations of cortical development (MCDs), which are now recognized as a leading cause of drug-resistant epilepsy and intellectual disability. In this heterogeneous group of disorders, macroscopic alterations of brain structure (eg, heterotopic nodules, small or absent gyri, double cortex) can be recognized and probably subtend a general reorganization of neuronal circuits. In this review, we provide an overview of the molecular mechanisms that are implicated in the generation of genetic MCDs associated with aberrations at various steps of neurogenesis and cortical development.
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Affiliation(s)
| | | | - Antonio Falace
- Aix-Marseille University, INSERM U1249, INMED, Marseille 13009, France
| | - Carlos Cardoso
- Aix-Marseille University, INSERM U1249, INMED, Marseille 13009, France
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20
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Jimenez J, Herrera DA, Vargas SA, Montoya J, Castillo M. β-Tubulinopathy caused by a mutation of the TUBB2B gene: magnetic resonance imaging findings of the brain. Neuroradiol J 2019; 32:148-150. [PMID: 30704335 PMCID: PMC6410457 DOI: 10.1177/1971400919828142] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Patients with mutations in tubulin-related genes usually present with brain malformations, intellectual disability, epilepsy, microcephaly and ocular abnormalities. In these patients the diagnosis can be suggested by neuroimaging findings. We report a 5-year-old patient with characteristic magnetic resonance imaging findings including malformation of cortical development, fused basal ganglia, large head of the caudate nuclei, absent anterior limbs of the internal capsules, corpus callosum dysgenesis and dysplastic cerebellar vermis. Sequencing of the TUBB2B gene confirmed a heterozygous mutation: c. 260C>A (p. Pro87Gln).
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Affiliation(s)
| | | | | | - Jorge Montoya
- Division of Medical Genetics, Hospital Universitario San Vicente Fundación, Colombia
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21
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The tubulin mutation database: A resource for the cytoskeleton community. Cytoskeleton (Hoboken) 2019; 76:186-191. [DOI: 10.1002/cm.21514] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 12/21/2018] [Accepted: 01/17/2019] [Indexed: 11/07/2022]
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22
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Challenges in managing epilepsy associated with focal cortical dysplasia in children. Epilepsy Res 2018; 145:1-17. [DOI: 10.1016/j.eplepsyres.2018.05.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Revised: 04/30/2018] [Accepted: 05/12/2018] [Indexed: 12/15/2022]
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23
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Tan AP, Chong WK, Mankad K. Comprehensive genotype-phenotype correlation in lissencephaly. Quant Imaging Med Surg 2018; 8:673-693. [PMID: 30211035 DOI: 10.21037/qims.2018.08.08] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Malformations of cortical development (MCD) are a heterogenous group of disorders with diverse genotypic and phenotypic variations. Lissencephaly is a subtype of MCD caused by defect in neuronal migration, which occurs between 12 and 24 weeks of gestation. The continuous advancement in the field of molecular genetics in the last decade has led to identification of at least 19 lissencephaly-related genes, most of which are related to microtubule structural proteins (tubulin) or microtubule-associated proteins (MAPs). The aim of this review article is to bring together current knowledge of gene mutations associated with lissencephaly and to provide a comprehensive genotype-phenotype correlation. Illustrative cases will be presented to facilitate the understanding of the described genotype-phenotype correlation.
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Affiliation(s)
- Ai Peng Tan
- Department of Diagnostic Imaging, National University Health System, Singapore.,Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore
| | - Wui Khean Chong
- Department of Neuroradiology, Great Ormond Street Hospital NHS Foundation Trust, London, UK
| | - Kshitij Mankad
- Department of Neuroradiology, Great Ormond Street Hospital NHS Foundation Trust, London, UK
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24
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Tubulin genes and malformations of cortical development. Eur J Med Genet 2018; 61:744-754. [PMID: 30016746 DOI: 10.1016/j.ejmg.2018.07.012] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 06/03/2018] [Accepted: 07/12/2018] [Indexed: 01/18/2023]
Abstract
A large number of genes encoding for tubulin proteins are expressed in the developing brain. Each is subject to specific spatial and temporal expression patterns. However, most are highly expressed in post-mitotic neurons during stages of neuronal migration and differentiation. The major tubulin subclasses (alpha- and beta-tubulin) share high sequence and structural homology. These globular proteins form heterodimers and subsequently co-assemble into microtubules. Microtubules are dynamic, cytoskeletal polymers which play key roles in cellular processes crucial for cortical development, including neuronal proliferation, migration and cortical laminar organisation. Mutations in seven genes encoding alpha-tubulin (TUBA1A), beta-tubulin (TUBB2A, TUBB2B, TUBB3, TUBB4A, TUBB) and gamma-tubulin (TUBG1) isoforms have been associated with a wide and overlapping range of brain malformations or "Tubulinopathies". The majority of cortical phenotypes include lissencephaly, polymicrogyria, microlissencephaly and simplified gyration. Well-known hallmarks of the tubulinopathies include dysmorphism of the basal ganglia (fusion of the caudate nucleus and putamen with absence of the anterior limb of the internal capsule), midline commissural structures hypoplasia and/or agenesis (anterior commissure, corpus callosum and fornix), hypoplasia of the oculomotor and optic nerves, cerebellar hypoplasia or dysplasia and dysmorphism of the hind-brain structures. The cortical and extra-cortical brain phenotypes observed are largely dependent on the specific tubulin gene affected. In the present review, all the published data on tubulin family gene mutations and the associated cortical phenotypes are summarized. In addition, the most typical neuroimaging patterns of malformations of cortical development associated with tubulin gene mutations detected on the basis of our own experience are described.
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Tubulinopathies continued: refining the phenotypic spectrum associated with variants in TUBG1. Eur J Hum Genet 2018; 26:1132-1142. [PMID: 29706637 PMCID: PMC6057922 DOI: 10.1038/s41431-018-0146-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Revised: 03/02/2018] [Accepted: 03/13/2018] [Indexed: 12/30/2022] Open
Abstract
Tubulinopathies are a heterogeneous group of conditions with a wide spectrum of clinical severity resulting from variants in genes of the tubulin superfamily. Variants in TUBG1 have been described in three patients with posterior predominant pachygyria and microcephaly. We here report eight additional patients with four novel heterozygous variants in TUBG1 identified by next-generation sequencing (NGS) analysis. All had severe motor and cognitive impairment and all except one developed seizures in early life. The core imaging features included a pachygyric cortex with posterior to anterior gradient, enlarged lateral ventricles most pronounced over the posterior horns, and variable degrees of reduced white matter volume. Basal ganglia, corpus callosum, brainstem, and cerebellum were often normal, in contrast to patients with variants in other tubulin genes where these structures are frequently malformed. The imaging phenotype associated with variants in TUBG1 is therefore more in line with the phenotype resulting from variants in LIS1 (a.k.a. PAFAH1B1). This difference may, at least in part, be explained by gamma-tubulin’s physiological function in microtubule nucleation, which differs from that of alpha and beta-tubulin.
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26
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Genetics and mechanisms leading to human cortical malformations. Semin Cell Dev Biol 2018; 76:33-75. [DOI: 10.1016/j.semcdb.2017.09.031] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 09/21/2017] [Accepted: 09/21/2017] [Indexed: 02/06/2023]
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27
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Huang H, Yang T, Shao Q, Majumder T, Mell K, Liu G. Human TUBB3 Mutations Disrupt Netrin Attractive Signaling. Neuroscience 2018; 374:155-171. [PMID: 29382549 DOI: 10.1016/j.neuroscience.2018.01.046] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Revised: 01/16/2018] [Accepted: 01/21/2018] [Indexed: 02/07/2023]
Abstract
Heterozygous missense mutations in human TUBB3 gene result in a spectrum of brain malformations associated with defects in axon guidance, neuronal migration and differentiation. However, the molecular mechanisms underlying mutation-related axon guidance abnormalities are unclear. Recent studies have shown that netrin-1, a canonical guidance cue, induced the interaction of TUBB3 with the netrin receptor deleted in colorectal cancer (DCC). Furthermore, TUBB3 is required for netrin-1-induced axon outgrowth, branching and pathfinding. Here, we provide evidence that TUBB3 mutations impair netrin/DCC signaling in the developing nervous system. The interaction of DCC with most TUBB3 mutants (eight out of twelve) is significantly reduced compared to the wild-type TUBB3. TUBB3 mutants R262C and A302V exhibit decreased subcellular colocalization with DCC in the growth cones of primary neurons. Netrin-1 increases the interaction of endogenous DCC with wild-type human TUBB3, but not R262C or A302V, in primary neurons. Netrin-1 also increases co-sedimentation of DCC with polymerized microtubules (MTs) in primary neurons expressing the wild-type TUBB3, but not R262C or A302V. Expression of either R262C or A302V not only suppresses netrin-1-induced neurite outgrowth, branching and attraction in vitro, but also causes defects in spinal cord commissural axon (CA) projection and pathfinding in ovo. Our study reveals that missense TUBB3 mutations specifically disrupt netrin/DCC-mediated attractive signaling.
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Affiliation(s)
- Huai Huang
- Department of Biological Sciences, University of Toledo, 2801 West Bancroft St., Toledo, OH 43606, USA
| | - Tao Yang
- Department of Biological Sciences, University of Toledo, 2801 West Bancroft St., Toledo, OH 43606, USA
| | - Qiangqiang Shao
- Department of Biological Sciences, University of Toledo, 2801 West Bancroft St., Toledo, OH 43606, USA
| | - Tanushree Majumder
- Department of Biological Sciences, University of Toledo, 2801 West Bancroft St., Toledo, OH 43606, USA
| | - Kristopher Mell
- Department of Biological Sciences, University of Toledo, 2801 West Bancroft St., Toledo, OH 43606, USA
| | - Guofa Liu
- Department of Biological Sciences, University of Toledo, 2801 West Bancroft St., Toledo, OH 43606, USA.
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Uncoupling of UNC5C with Polymerized TUBB3 in Microtubules Mediates Netrin-1 Repulsion. J Neurosci 2017; 37:5620-5633. [PMID: 28483977 DOI: 10.1523/jneurosci.2617-16.2017] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Revised: 04/22/2017] [Accepted: 04/28/2017] [Indexed: 11/21/2022] Open
Abstract
Modulation of microtubule (MT) dynamics is a key event of cytoskeleton remodeling in the growth cone (GC) during axon outgrowth and pathfinding. Our previous studies have shown that the direct interaction of netrin receptor DCC and DSCAM with polymerized TUBB3, a neuron-specific MT subunit in the brain, is required for netrin-1-mediated axon outgrowth, branching, and attraction. Here, we show that uncoupling of polymerized TUBB3 with netrin-1-repulsive receptor UNC5C is involved in netrin-1-mediated axonal repulsion. TUBB3 directly interacted with UNC5C and partially colocalized with UNC5C in the peripheral area of the GC of primary neurons from the cerebellar external granule layer of P2 mouse pups of both sexes. Netrin-1 reduced this interaction as well as the colocalization of UNC5C and TUBB3 in the GC. Results from the in vitro cosedimentation assay indicated that UNC5C interacted with polymerized TUBB3 in MTs and netrin-1 decreased this interaction. Knockdown of either TUBB3 or UNC5C blocked netrin-1-promoted axon repulsion in vitro and caused defects in axon projection of DRG toward the spinal cord in vivo Furthermore, live-cell imaging of end-binding protein 3 tagged with EGFP (EB3-GFP) in primary external granule layer cells showed that netrin-1 differentially increased MT dynamics in the GC with more MT growth in the distal than the proximal region of the GC during repulsion, and knockdown of either UNC5C or TUBB3 abolished the netrin-1 effect. Together, these data indicate that the disengagement of UNC5C with polymerized TUBB3 plays an essential role in netrin-1/UNC5C-mediated axon repulsion.SIGNIFICANCE STATEMENT Proper regulation of microtubule (MT) dynamics in the growth cone plays an important role in axon guidance. However, whether guidance cues modulate MT dynamics directly or indirectly is unclear. Here, we report that dissociation of UNC5C and polymerized TUBB3, the highly dynamic β-tubulin isoform in neurons, is essential for netrin-1/UNC5C-promoted axon repulsion. These results not only provide a working model of direct modulation of MTs by guidance cues in growth cone navigation but also help us to understand molecular mechanisms underlying developmental brain disorders associated with TUBB3 mutations.
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Minoura I. Towards an understanding of the isotype-specific functions of tubulin in neurons: Technical advances in tubulin expression and purification. Neurosci Res 2017; 122:1-8. [PMID: 28412269 DOI: 10.1016/j.neures.2017.04.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Revised: 03/29/2017] [Accepted: 04/07/2017] [Indexed: 12/20/2022]
Abstract
Microtubules are cytoskeletal filaments critical for determining the complex morphology of neurons, as well as the basic architecture and organization of mitosis in all eukaryotic cells. Microtubules in humans are composed of 8 α- and 9 β-tubulin isotypes, each of which is encoded by different members of a multi-gene family. The expression pattern of tubulin isotypes, in addition to isotype-specific post-translational modifications, is thought to be critical for the morphogenesis of axons and dendrites. Recent studies revealed that several neurodevelopmental disorders are caused by mutations of specific tubulin isotypes, suggesting that each tubulin isotype has distinct functions. Therefore, in vitro and in vivo functional analyses of tubulin isotypes are important to understand the pathogenesis of developmental disorders. Likewise, analysis of developmental disorders may clarify the function of different tubulin isotypes. In this respect, both the preparation of specific tubulin isotypes and of specific mutant tubulin proteins is critical to understanding the function of tubulin. In the last 20 years, various methods have been developed to study functional differences between tubulin isotypes and the functional defects caused by tubulin mutations. These technical achievements have been discussed in this review. The function of tubulin/microtubules in neuronal morphogenesis as revealed through these techniques has also been described.
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Affiliation(s)
- Itsushi Minoura
- Laboratory for Molecular Biophysics, Brain Science Institute, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; Goryo Chemical Inc., Earee Bldg. 5F, Kita 8 Nishi 18-35-100, Chuo-ku, Sapporo 060-0008, Japan.
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30
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Sweet KM, Shaw DW, Chapman T. Cerebral palsy and seizures in a child with tubulinopathy pattern dysgenesis and focal cortical dysplasia. Radiol Case Rep 2017; 12:396-400. [PMID: 28491196 PMCID: PMC5417618 DOI: 10.1016/j.radcr.2016.12.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Revised: 12/01/2016] [Accepted: 12/19/2016] [Indexed: 12/23/2022] Open
Abstract
A 7-year-old boy with a history of spasticity, global developmental delay, and seizures was given the general diagnosis of cerebral palsy at an early age. Chromosomal array analysis performed at an outside center was normal. The patient's family sought neurodevelopmental pediatric care at a new institution following a move out of state. Electroencephalography confirmed abnormal epileptogenic activity. Brain magnetic resonance imaging showed findings consistent with a tubulin gene defect (tubulinopathy) and of focal cortical dysplasia, as well as evidence of a remote occipital lobe injury. This case report describes the various brain magnetic resonance findings suggestive of a tubulin gene defect and raises the possibility of focal cortical dysplasia manifesting as a result of tubulin dysfunction.
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Affiliation(s)
- Kevin M. Sweet
- University of Miami Miller School of Medicine, Miami, FL, USA
| | - Dennis W.W. Shaw
- Department of Radiology, Seattle Children’s Hospital, Mail Stop MA.07.220, 4800 Sand Point Way NE, Seattle, WA 98105, USA
- Department of Radiology, University of Washington School of Medicine, Campus Box 359300, 1959 Pacific St, Seattle, WA 98195-9300, USA
| | - Teresa Chapman
- Department of Radiology, Seattle Children’s Hospital, Mail Stop MA.07.220, 4800 Sand Point Way NE, Seattle, WA 98105, USA
- Department of Radiology, University of Washington School of Medicine, Campus Box 359300, 1959 Pacific St, Seattle, WA 98195-9300, USA
- Corresponding author.
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31
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Abstract
Malformations of cortical development (MCD) represent a major cause of developmental disabilities, severe epilepsy, and reproductive disadvantage. Genes that have been associated to MCD are mainly involved in cell proliferation and specification, neuronal migration, and late cortical organization. Lissencephaly-pachygyria-severe band heterotopia are diffuse neuronal migration disorders causing severe global neurological impairment. Abnormalities of the LIS1, DCX, ARX, RELN, VLDLR, ACTB, ACTG1, TUBG1, KIF5C, KIF2A, and CDK5 genes have been associated with these malformations. More recent studies have also established a relationship between lissencephaly, with or without associated microcephaly, corpus callosum dysgenesis as well as cerebellar hypoplasia, and at times, a morphological pattern consistent with polymicrogyria with mutations of several genes (TUBA1A, TUBA8, TUBB, TUBB2B, TUBB3, and DYNC1H1), regulating the synthesis and function of microtubule and centrosome key components and hence defined as tubulinopathies. MCD only affecting subsets of neurons, such as mild subcortical band heterotopia and periventricular heterotopia, have been associated with abnormalities of the DCX, FLN1A, and ARFGEF2 genes and cause neurological and cognitive impairment that vary from severe to mild deficits. Polymicrogyria results from abnormal late cortical organization and is inconstantly associated with abnormal neuronal migration. Localized polymicrogyria has been associated with anatomo-specific deficits, including disorders of language and higher cognition. Polymicrogyria is genetically heterogeneous, and only in a small minority of patients, a definite genetic cause has been identified. Megalencephaly with normal cortex or polymicrogyria by MRI imaging, hemimegalencephaly and focal cortical dysplasia can all result from mutations in genes of the PI3K-AKT-mTOR pathway. Postzygotic mutations have been described for most MCD and can be limited to the dysplastic tissue in the less diffuse forms.
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Affiliation(s)
- Elena Parrini
- Pediatric Neurology, Neurogenetics and Neurobiology Unit and Laboratories, Department of Neuroscience, A. Meyer Children's Hospital, University of Florence, Florence, Italy
| | - Valerio Conti
- Pediatric Neurology, Neurogenetics and Neurobiology Unit and Laboratories, Department of Neuroscience, A. Meyer Children's Hospital, University of Florence, Florence, Italy
| | - William B Dobyns
- Division of Genetic Medicine, Department of Pediatrics, University of Washington, and Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, Wash., USA
| | - Renzo Guerrini
- Pediatric Neurology, Neurogenetics and Neurobiology Unit and Laboratories, Department of Neuroscience, A. Meyer Children's Hospital, University of Florence, Florence, Italy
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32
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Chakraborti S, Natarajan K, Curiel J, Janke C, Liu J. The emerging role of the tubulin code: From the tubulin molecule to neuronal function and disease. Cytoskeleton (Hoboken) 2016; 73:521-550. [PMID: 26934450 DOI: 10.1002/cm.21290] [Citation(s) in RCA: 102] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 02/18/2016] [Accepted: 02/26/2016] [Indexed: 11/11/2022]
Abstract
Across different cell types and tissues, microtubules are assembled from highly conserved dimers of α- and β-tubulin. Despite their highly similar structures, microtubules have functional heterogeneity, generated either by the expression of different tubulin genes, encoding distinct isotypes, or by posttranslational modifications of tubulin. This genetically encoded and posttranslational generated heterogeneity of tubulin-the "tubulin code"-has the potential to modulate microtubule structure, dynamics, and interactions with associated proteins. The tubulin code is therefore believed to regulate microtubule functions on a cellular and sub-cellular level. This review highlights the importance of the tubulin code for tubulin structure, as well as on microtubule dynamics and functions in neurons. It further summarizes recent developments in the understanding of mutations in tubulin genes, and how they are linked to neurodegenerative and neurodevelopmental disorders. The current advances in the knowledge of the tubulin code on the molecular and the functional level will certainly lead to a better understanding of how complex signaling events control microtubule functions, especially in cells of the nervous system. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Soumyananda Chakraborti
- Institut Curie, PSL Research University, CNRS, INSERM, UMR 3348, Orsay, F-91405, France.,Université Paris Sud, Université Paris-Saclay, CNRS, UMR 3348, Orsay, F-91405, France
| | - Kathiresan Natarajan
- Institut Curie, PSL Research University, CNRS, INSERM, UMR 3348, Orsay, F-91405, France.,Université Paris Sud, Université Paris-Saclay, CNRS, UMR 3348, Orsay, F-91405, France
| | - Julian Curiel
- Children's National Health System, Center for Neuroscience Research, Washington, District of Columbia
| | - Carsten Janke
- Institut Curie, PSL Research University, CNRS, INSERM, UMR 3348, Orsay, F-91405, France. .,Université Paris Sud, Université Paris-Saclay, CNRS, UMR 3348, Orsay, F-91405, France.
| | - Judy Liu
- Children's National Health System, Center for Neuroscience Research, Washington, District of Columbia.
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33
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Hutchins BI, Kotan LD, Taylor-Burds C, Ozkan Y, Cheng PJ, Gurbuz F, Tiong JDR, Mengen E, Yuksel B, Topaloglu AK, Wray S. CCDC141 Mutation Identified in Anosmic Hypogonadotropic Hypogonadism (Kallmann Syndrome) Alters GnRH Neuronal Migration. Endocrinology 2016; 157:1956-66. [PMID: 27014940 PMCID: PMC4870868 DOI: 10.1210/en.2015-1846] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The first mutation in a gene associated with a neuronal migration disorder was identified in patients with Kallmann Syndrome, characterized by hypogonadotropic hypogonadism and anosmia. This pathophysiological association results from a defect in the development of the GnRH and the olfactory system. A recent genetic screening of Kallmann Syndrome patients revealed a novel mutation in CCDC141. Little is known about CCDC141, which encodes a coiled-coil domain containing protein. Here, we show that Ccdc141 is expressed in GnRH neurons and olfactory fibers and that knockdown of Ccdc141 reduces GnRH neuronal migration. Our findings in human patients and mouse models predict that CCDC141 takes part in embryonic migration of GnRH neurons enabling them to form a hypothalamic neuronal network to initiate pulsatile GnRH secretion and reproductive function.
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Affiliation(s)
- B Ian Hutchins
- National Institute of Neurological Disorders and Stroke (B.I.H., C.T.-B., P.J.C., J.D.R.T., S.W.), National Institutes of Health, Bethesda, Maryland 20892; Department of Biotechnology (L.D.K., A.K.T.), Institute of Sciences, Cukurova University, 01330 Adana, Turkey; Fırat University (Y.O.), 23119 Elazıg, Turkey; and Division of Pediatric Endocrinology (F.G., E.M., B.Y., A.K.T.), Faculty of Medicine, Cukurova University, 01330 Adana, Turkey
| | - L Damla Kotan
- National Institute of Neurological Disorders and Stroke (B.I.H., C.T.-B., P.J.C., J.D.R.T., S.W.), National Institutes of Health, Bethesda, Maryland 20892; Department of Biotechnology (L.D.K., A.K.T.), Institute of Sciences, Cukurova University, 01330 Adana, Turkey; Fırat University (Y.O.), 23119 Elazıg, Turkey; and Division of Pediatric Endocrinology (F.G., E.M., B.Y., A.K.T.), Faculty of Medicine, Cukurova University, 01330 Adana, Turkey
| | - Carol Taylor-Burds
- National Institute of Neurological Disorders and Stroke (B.I.H., C.T.-B., P.J.C., J.D.R.T., S.W.), National Institutes of Health, Bethesda, Maryland 20892; Department of Biotechnology (L.D.K., A.K.T.), Institute of Sciences, Cukurova University, 01330 Adana, Turkey; Fırat University (Y.O.), 23119 Elazıg, Turkey; and Division of Pediatric Endocrinology (F.G., E.M., B.Y., A.K.T.), Faculty of Medicine, Cukurova University, 01330 Adana, Turkey
| | - Yusuf Ozkan
- National Institute of Neurological Disorders and Stroke (B.I.H., C.T.-B., P.J.C., J.D.R.T., S.W.), National Institutes of Health, Bethesda, Maryland 20892; Department of Biotechnology (L.D.K., A.K.T.), Institute of Sciences, Cukurova University, 01330 Adana, Turkey; Fırat University (Y.O.), 23119 Elazıg, Turkey; and Division of Pediatric Endocrinology (F.G., E.M., B.Y., A.K.T.), Faculty of Medicine, Cukurova University, 01330 Adana, Turkey
| | - Paul J Cheng
- National Institute of Neurological Disorders and Stroke (B.I.H., C.T.-B., P.J.C., J.D.R.T., S.W.), National Institutes of Health, Bethesda, Maryland 20892; Department of Biotechnology (L.D.K., A.K.T.), Institute of Sciences, Cukurova University, 01330 Adana, Turkey; Fırat University (Y.O.), 23119 Elazıg, Turkey; and Division of Pediatric Endocrinology (F.G., E.M., B.Y., A.K.T.), Faculty of Medicine, Cukurova University, 01330 Adana, Turkey
| | - Fatih Gurbuz
- National Institute of Neurological Disorders and Stroke (B.I.H., C.T.-B., P.J.C., J.D.R.T., S.W.), National Institutes of Health, Bethesda, Maryland 20892; Department of Biotechnology (L.D.K., A.K.T.), Institute of Sciences, Cukurova University, 01330 Adana, Turkey; Fırat University (Y.O.), 23119 Elazıg, Turkey; and Division of Pediatric Endocrinology (F.G., E.M., B.Y., A.K.T.), Faculty of Medicine, Cukurova University, 01330 Adana, Turkey
| | - Jean D R Tiong
- National Institute of Neurological Disorders and Stroke (B.I.H., C.T.-B., P.J.C., J.D.R.T., S.W.), National Institutes of Health, Bethesda, Maryland 20892; Department of Biotechnology (L.D.K., A.K.T.), Institute of Sciences, Cukurova University, 01330 Adana, Turkey; Fırat University (Y.O.), 23119 Elazıg, Turkey; and Division of Pediatric Endocrinology (F.G., E.M., B.Y., A.K.T.), Faculty of Medicine, Cukurova University, 01330 Adana, Turkey
| | - Eda Mengen
- National Institute of Neurological Disorders and Stroke (B.I.H., C.T.-B., P.J.C., J.D.R.T., S.W.), National Institutes of Health, Bethesda, Maryland 20892; Department of Biotechnology (L.D.K., A.K.T.), Institute of Sciences, Cukurova University, 01330 Adana, Turkey; Fırat University (Y.O.), 23119 Elazıg, Turkey; and Division of Pediatric Endocrinology (F.G., E.M., B.Y., A.K.T.), Faculty of Medicine, Cukurova University, 01330 Adana, Turkey
| | - Bilgin Yuksel
- National Institute of Neurological Disorders and Stroke (B.I.H., C.T.-B., P.J.C., J.D.R.T., S.W.), National Institutes of Health, Bethesda, Maryland 20892; Department of Biotechnology (L.D.K., A.K.T.), Institute of Sciences, Cukurova University, 01330 Adana, Turkey; Fırat University (Y.O.), 23119 Elazıg, Turkey; and Division of Pediatric Endocrinology (F.G., E.M., B.Y., A.K.T.), Faculty of Medicine, Cukurova University, 01330 Adana, Turkey
| | - A Kemal Topaloglu
- National Institute of Neurological Disorders and Stroke (B.I.H., C.T.-B., P.J.C., J.D.R.T., S.W.), National Institutes of Health, Bethesda, Maryland 20892; Department of Biotechnology (L.D.K., A.K.T.), Institute of Sciences, Cukurova University, 01330 Adana, Turkey; Fırat University (Y.O.), 23119 Elazıg, Turkey; and Division of Pediatric Endocrinology (F.G., E.M., B.Y., A.K.T.), Faculty of Medicine, Cukurova University, 01330 Adana, Turkey
| | - Susan Wray
- National Institute of Neurological Disorders and Stroke (B.I.H., C.T.-B., P.J.C., J.D.R.T., S.W.), National Institutes of Health, Bethesda, Maryland 20892; Department of Biotechnology (L.D.K., A.K.T.), Institute of Sciences, Cukurova University, 01330 Adana, Turkey; Fırat University (Y.O.), 23119 Elazıg, Turkey; and Division of Pediatric Endocrinology (F.G., E.M., B.Y., A.K.T.), Faculty of Medicine, Cukurova University, 01330 Adana, Turkey
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Moffat JJ, Ka M, Jung EM, Kim WY. Genes and brain malformations associated with abnormal neuron positioning. Mol Brain 2015; 8:72. [PMID: 26541977 PMCID: PMC4635534 DOI: 10.1186/s13041-015-0164-4] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 10/31/2015] [Indexed: 01/05/2023] Open
Abstract
Neuronal positioning is a fundamental process during brain development. Abnormalities in this process cause several types of brain malformations and are linked to neurodevelopmental disorders such as autism, intellectual disability, epilepsy, and schizophrenia. Little is known about the pathogenesis of developmental brain malformations associated with abnormal neuron positioning, which has hindered research into potential treatments. However, recent advances in neurogenetics provide clues to the pathogenesis of aberrant neuronal positioning by identifying causative genes. This may help us form a foundation upon which therapeutic tools can be developed. In this review, we first provide a brief overview of neural development and migration, as they relate to defects in neuronal positioning. We then discuss recent progress in identifying genes and brain malformations associated with aberrant neuronal positioning during human brain development.
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Affiliation(s)
- Jeffrey J Moffat
- Department of Developmental Neuroscience, Munroe-Meyer Institute, University of Nebraska Medical Center, 985960 Nebraska Medical Center, Omaha, NE, 68198-5960, USA.
| | - Minhan Ka
- Department of Developmental Neuroscience, Munroe-Meyer Institute, University of Nebraska Medical Center, 985960 Nebraska Medical Center, Omaha, NE, 68198-5960, USA.
| | - Eui-Man Jung
- Department of Developmental Neuroscience, Munroe-Meyer Institute, University of Nebraska Medical Center, 985960 Nebraska Medical Center, Omaha, NE, 68198-5960, USA.
| | - Woo-Yang Kim
- Department of Developmental Neuroscience, Munroe-Meyer Institute, University of Nebraska Medical Center, 985960 Nebraska Medical Center, Omaha, NE, 68198-5960, USA.
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Recessive Mutations in POLR3B Encoding RNA Polymerase III Subunit Causing Diffuse Hypomyelination in Patients with 4H Leukodystrophy with Polymicrogyria and Cataracts. Clin Neuroradiol 2015; 27:213-220. [PMID: 26478204 PMCID: PMC5487884 DOI: 10.1007/s00062-015-0472-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Accepted: 09/29/2015] [Indexed: 02/06/2023]
Abstract
The diagnosis of 4H leukodystrophy (hypomyelination, hypogonadotropic hypogonadism, and hypodontia) is based on clinical findings and magnetic resonance imaging (MRI). Recently, mutations of the genes encoding Pol III (RNA polymerase III) subunit A (POLR3A) and subunit B (POL3B) have been identified as the genetic causes of hypomyelination. We describe two Polish female siblings aged 5 and 10 years with compound heterozygous mutations in POLR3B. They both presented with similar clinical symptoms and MRI findings presenting as 4H leukodystrophy, and the association of polymicrogyria and cataract. According to our observation in young children with the absence of hypogonadotropic hypogonadism, brain MRI pattern is very essential in proper early diagnosis of 4H leukodystrophy. All clinical and radiological results are of course helpful, however genetic conformation is always necessary.
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Oegema R, Cushion TD, Phelps IG, Chung SK, Dempsey JC, Collins S, Mullins JGL, Dudding T, Gill H, Green AJ, Dobyns WB, Ishak GE, Rees MI, Doherty D. Recognizable cerebellar dysplasia associated with mutations in multiple tubulin genes. Hum Mol Genet 2015; 24:5313-25. [PMID: 26130693 DOI: 10.1093/hmg/ddv250] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 06/24/2015] [Indexed: 01/06/2023] Open
Abstract
Mutations in alpha- and beta-tubulins are increasingly recognized as a major cause of malformations of cortical development (MCD), typically lissencephaly, pachygyria and polymicrogyria; however, sequencing tubulin genes in large cohorts of MCD patients has detected tubulin mutations in only 1-13%. We identified patients with a highly characteristic cerebellar dysplasia but without lissencephaly, pachygyria and polymicrogyria typically associated with tubulin mutations. Remarkably, in seven of nine patients (78%), targeted sequencing revealed mutations in three different tubulin genes (TUBA1A, TUBB2B and TUBB3), occurring de novo or inherited from a mosaic parent. Careful re-review of the cortical phenotype on brain imaging revealed only an irregular pattern of gyri and sulci, for which we propose the term tubulinopathy-related dysgyria. Basal ganglia (100%) and brainstem dysplasia (80%) were common features. On the basis of in silico structural predictions, the mutations affect amino acids in diverse regions of the alpha-/beta-tubulin heterodimer, including the nucleotide binding pocket. Cell-based assays of tubulin dynamics reveal various effects of the mutations on incorporation into microtubules: TUBB3 p.Glu288Lys and p.Pro357Leu do not incorporate into microtubules at all, whereas TUBB2B p.Gly13Ala shows reduced incorporation and TUBA1A p.Arg214His incorporates fully, but at a slower rate than wild-type. The broad range of effects on microtubule incorporation is at odds with the highly stereotypical clinical phenotype, supporting differential roles for the three tubulin genes involved. Identifying this highly characteristic phenotype is important due to the low recurrence risk compared with the other (recessive) cerebellar dysplasias and the apparent lack of non-neurological medical issues.
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Affiliation(s)
- Renske Oegema
- Department of Clinical Genetics, Erasmus MC University Medical Center, Rotterdam, The Netherlands,
| | | | | | - Seo-Kyung Chung
- Institute of Life Science, College of Medicine and Wales Epilepsy Research Network (WERN), College of Medicine, Swansea University, Swansea SA2 8PP, UK
| | | | - Sarah Collins
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA 98101, USA
| | | | - Tracy Dudding
- Hunter Genetics, Waratah, New South Wales, Australia, University of Newcastle, Callaghan, New South Wales, Australia
| | - Harinder Gill
- National Centre for Medical Genetics, Our Lady's Children's Hospital, Dublin 12, Ireland and
| | - Andrew J Green
- National Centre for Medical Genetics, Our Lady's Children's Hospital, Dublin 12, Ireland and School of Medicine and Medical Science, University College Dublin, Dublin 4, Ireland
| | - William B Dobyns
- Department of Pediatrics, Department of Neurology and Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA 98101, USA
| | - Gisele E Ishak
- Department of Radiology, Seattle Children's Hospital and University of Washington, Seattle, WA 98195, USA
| | - Mark I Rees
- Institute of Life Science, College of Medicine and Wales Epilepsy Research Network (WERN), College of Medicine, Swansea University, Swansea SA2 8PP, UK
| | - Dan Doherty
- Department of Pediatrics, Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA 98101, USA,
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Barkovich AJ, Dobyns WB, Guerrini R. Malformations of cortical development and epilepsy. Cold Spring Harb Perspect Med 2015; 5:a022392. [PMID: 25934463 DOI: 10.1101/cshperspect.a022392] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Malformations of cortical development (MCDs) are an important cause of epilepsy and an extremely interesting group of disorders from the perspective of brain development and its perturbations. Many new MCDs have been described in recent years as a result of improvements in imaging, genetic testing, and understanding of the effects of mutations on the ability of their protein products to correctly function within the molecular pathways by which the brain functions. In this review, most of the major MCDs are reviewed from a clinical, embryological, and genetic perspective. The most recent literature regarding clinical diagnosis, mechanisms of development, and future paths of research are discussed.
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Affiliation(s)
- A James Barkovich
- Department of Radiology and Biomedical Imaging, Neurology, Pediatrics, and Neurosurgery, University of California, San Francisco, San Francisco, California 94143-0628
| | - William B Dobyns
- Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, Washington 98101
| | - Renzo Guerrini
- Pediatric Neurology Unit and Laboratories, Children's Hospital A. Meyer, University of Florence, Florence 50139, Italy
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Romaniello R, Arrigoni F, Bassi MT, Borgatti R. Mutations in α- and β-tubulin encoding genes: implications in brain malformations. Brain Dev 2015; 37:273-80. [PMID: 25008804 DOI: 10.1016/j.braindev.2014.06.002] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Revised: 05/26/2014] [Accepted: 06/02/2014] [Indexed: 12/24/2022]
Abstract
The tubulin gene family is mainly expressed in post-mitotic neurons during cortical development with a specific spatial and temporal expression pattern. Members of this family encode dimeric proteins consisting of two closely related subunits (α and β), representing the major constituents of microtubules. Tubulin genes play a crucial role in the mechanisms of the Central Nervous System development such as neuronal migration and axonal guidance (axon outgrowth and maintenance). Different mutations in α/β-tubulin genes (TUBA1A, TUBA8, TUBB2A, TUBB4A, TUBB2B, TUBB3, and TUBB) might alter the dynamic properties and functions of microtubules in several ways, effecting a reduction in the number of functional tubulin heterodimers and causing alterations in GTP binding and disruptions of the binding of other proteins to microtubules (motor proteins and other microtubule interacting proteins). In recent years an increasing number of brain malformations has been associated with mutations in tubulin genes: malformations of cortical development such as lissencephaly and various grades of gyral disorganization, focal or diffuse polymicrogyria and open or closed-lips schizencephaly as likely consequences of an altered neuronal migration process; abnormalities or agenesis of the midline commissural structures (anterior commissure, corpus callosum and fornix), hypoplasia of the oculomotor and optic nerves, dysmorphisms of the hind-brain as expression of axon guidance disorders. Dysmorphisms of the basal ganglia (fusion between the caudate nucleus and putamen with absence of the anterior limb of the internal capsule) and hippocampi were also observed. A rare form of leukoencephalopathy characterized by hypomyelination with atrophy of the basal ganglia an cerebellum (H-ABC) was also recently described. The present review, describing the structural and functional features of tubulin genes, aims to revise the main cerebral associated malformations and related clinical aspects, suggesting a genotype-phenotype correlation.
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Affiliation(s)
- Romina Romaniello
- Neuropsychiatry and Neurorehabilitation Unit, IRCCS Eugenio Medea, Bosisio Parini, Lecco, Italy
| | - Filippo Arrigoni
- Neuroimaging Unit, IRCCS Eugenio Medea, Bosisio Parini, Lecco, Italy
| | - Maria Teresa Bassi
- Laboratory of Molecular Biology, IRCCS Eugenio Medea, Bosisio Parini, Lecco, Italy
| | - Renato Borgatti
- Neuropsychiatry and Neurorehabilitation Unit, IRCCS Eugenio Medea, Bosisio Parini, Lecco, Italy.
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Bahi-Buisson N, Poirier K, Fourniol F, Saillour Y, Valence S, Lebrun N, Hully M, Bianco CF, Boddaert N, Elie C, Lascelles K, Souville I, Beldjord C, Chelly J. The wide spectrum of tubulinopathies: what are the key features for the diagnosis? ACTA ACUST UNITED AC 2014; 137:1676-700. [PMID: 24860126 DOI: 10.1093/brain/awu082] [Citation(s) in RCA: 206] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Complex cortical malformations associated with mutations in tubulin genes: TUBA1A, TUBA8, TUBB2B, TUBB3, TUBB5 and TUBG1 commonly referred to as tubulinopathies, are a heterogeneous group of conditions with a wide spectrum of clinical severity. Among the 106 patients selected as having complex cortical malformations, 45 were found to carry mutations in TUBA1A (42.5%), 18 in TUBB2B (16.9%), 11 in TUBB3 (10.4%), three in TUBB5 (2.8%), and three in TUBG1 (2.8%). No mutations were identified in TUBA8. Systematic review of patients' neuroimaging and neuropathological data allowed us to distinguish at least five cortical malformation syndromes: (i) microlissencephaly (n = 12); (ii) lissencephaly (n = 19); (iii) central pachygyria and polymicrogyria-like cortical dysplasia (n = 24); (iv) generalized polymicrogyria-like cortical dysplasia (n = 6); and (v) a 'simplified' gyral pattern with area of focal polymicrogyria (n = 19). Dysmorphic basal ganglia are the hallmark of tubulinopathies (found in 75% of cases) and are present in 100% of central pachygyria and polymicrogyria-like cortical dysplasia and simplified gyral malformation syndromes. Tubulinopathies are also characterized by a high prevalence of corpus callosum agenesis (32/80; 40%), and mild to severe cerebellar hypoplasia and dysplasia (63/80; 78.7%). Foetal cases (n = 25) represent the severe end of the spectrum and show specific abnormalities that provide insights into the underlying pathophysiology. The overall complexity of tubulinopathies reflects the pleiotropic effects of tubulins and their specific spatio-temporal profiles of expression. In line with previous reports, this large cohort further clarifies overlapping phenotypes between tubulinopathies and although current structural data do not allow prediction of mutation-related phenotypes, within each mutated gene there is an associated predominant pattern of cortical dysgenesis allowing some phenotype-genotype correlation. The core phenotype of TUBA1A and TUBG1 tubulinopathies are lissencephalies and microlissencephalies, whereas TUBB2B tubulinopathies show in the majority, centrally predominant polymicrogyria-like cortical dysplasia. By contrast, TUBB3 and TUBB5 mutations cause milder malformations with focal or multifocal polymicrogyria-like cortical dysplasia with abnormal and simplified gyral pattern.
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Affiliation(s)
- Nadia Bahi-Buisson
- 1 Institut Cochin, Université Paris-Descartes, CNRS (UMR 8104), Paris, France2 Inserm, U1016, Paris, France3 Université Paris Descartes, Sorbonne Paris Cité, Institut Imagine, Paris, France4 INSERM UMR-1163, Embryology and genetics of congenital malformations, Paris, France5 Service de Neurologie pédiatrique, Assistance Publique-Hôpitaux de Paris (AP-HP), hôpital Necker, Paris, France
| | - Karine Poirier
- 1 Institut Cochin, Université Paris-Descartes, CNRS (UMR 8104), Paris, France2 Inserm, U1016, Paris, France
| | | | - Yoann Saillour
- 1 Institut Cochin, Université Paris-Descartes, CNRS (UMR 8104), Paris, France2 Inserm, U1016, Paris, France
| | - Stéphanie Valence
- 1 Institut Cochin, Université Paris-Descartes, CNRS (UMR 8104), Paris, France2 Inserm, U1016, Paris, France
| | - Nicolas Lebrun
- 1 Institut Cochin, Université Paris-Descartes, CNRS (UMR 8104), Paris, France2 Inserm, U1016, Paris, France
| | - Marie Hully
- 5 Service de Neurologie pédiatrique, Assistance Publique-Hôpitaux de Paris (AP-HP), hôpital Necker, Paris, France
| | | | - Nathalie Boddaert
- 8 Service de Radiologie Pédiatrique, AP-HP, hôpital Necker, Paris, France9 Inserm, U797-INSERM-CEA, Service Hospitalier Frédéric Joliot, CEA, 4, place du General Leclerc, 91406, Orsay, France
| | - Caroline Elie
- 10 BioInformatic Department-AP-HP, hôpital Necker-Enfants Malades, Paris, France
| | | | - Isabelle Souville
- 12 Service de Biologie Moleculaire et Genetique, Pavillon Cassini AP-HP, Hôpital Cochin, Paris, France
| | | | - Cherif Beldjord
- 12 Service de Biologie Moleculaire et Genetique, Pavillon Cassini AP-HP, Hôpital Cochin, Paris, France
| | - Jamel Chelly
- 1 Institut Cochin, Université Paris-Descartes, CNRS (UMR 8104), Paris, France2 Inserm, U1016, Paris, France
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Fallet-Bianco C, Laquerrière A, Poirier K, Razavi F, Guimiot F, Dias P, Loeuillet L, Lascelles K, Beldjord C, Carion N, Toussaint A, Revencu N, Addor MC, Lhermitte B, Gonzales M, Martinovich J, Bessieres B, Marcy-Bonnière M, Jossic F, Marcorelles P, Loget P, Chelly J, Bahi-Buisson N. Mutations in tubulin genes are frequent causes of various foetal malformations of cortical development including microlissencephaly. Acta Neuropathol Commun 2014; 2:69. [PMID: 25059107 PMCID: PMC4222268 DOI: 10.1186/2051-5960-2-69] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Accepted: 06/04/2014] [Indexed: 01/18/2023] Open
Abstract
Complex cortical malformations associated with mutations in tubulin genes are commonly referred to as “Tubulinopathies”. To further characterize the mutation frequency and phenotypes associated with tubulin mutations, we studied a cohort of 60 foetal cases. Twenty-six tubulin mutations were identified, of which TUBA1A mutations were the most prevalent (19 cases), followed by TUBB2B (6 cases) and TUBB3 (one case). Three subtypes clearly emerged. The most frequent (n = 13) was microlissencephaly with corpus callosum agenesis, severely hypoplastic brainstem and cerebellum. The cortical plate was either absent (6/13), with a 2–3 layered pattern (5/13) or less frequently thickened (2/13), often associated with neuroglial overmigration (4/13). All cases had voluminous germinal zones and ganglionic eminences. The second subtype was lissencephaly (n = 7), either classical (4/7) or associated with cerebellar hypoplasia (3/7) with corpus callosum agenesis (6/7). All foetuses with lissencephaly and cerebellar hypoplasia carried distinct TUBA1A mutations, while those with classical lissencephaly harbored recurrent mutations in TUBA1A (3 cases) or TUBB2B (1 case). The third group was polymicrogyria-like cortical dysplasia (n = 6), consisting of asymmetric multifocal or generalized polymicrogyria with inconstant corpus callosum agenesis (4/6) and hypoplastic brainstem and cerebellum (3/6). Polymicrogyria was either unlayered or 4-layered with neuronal heterotopias (5/6) and occasional focal neuroglial overmigration (2/6). Three had TUBA1A mutations and 3 TUBB2B mutations. Foetal TUBA1A tubulinopathies most often consist in microlissencephaly or classical lissencephaly with corpus callosum agenesis, but polymicrogyria may also occur. Conversely, TUBB2B mutations are responsible for either polymicrogyria (4/6) or microlissencephaly (2/6).
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Liu G, Dwyer T. Microtubule dynamics in axon guidance. Neurosci Bull 2014; 30:569-83. [PMID: 24968808 DOI: 10.1007/s12264-014-1444-6] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Accepted: 04/10/2014] [Indexed: 12/18/2022] Open
Abstract
Precise modulation of the cytoskeleton is involved in a variety of cellular processes including cell division, migration, polarity, and adhesion. In developing post-mitotic neurons, extracellular guidance cues not only trigger signaling cascades that act at a distance to indirectly regulate microtubule distribution, and assembly and disassembly in the growth cone, but also directly modulate microtubule stability and dynamics through coupling of guidance receptors with microtubules to control growth-cone turning. Microtubule-associated proteins including classical microtubule-associated proteins and microtubule plus-end tracking proteins are required for modulating microtubule dynamics to influence growth-cone steering. Multiple key signaling components, such as calcium, small GTPases, glycogen synthase kinase-3β, and c-Jun N-terminal kinase, link upstream signal cascades to microtubule stability and dynamics in the growth cone to control axon outgrowth and projection. Understanding the functions and regulation of microtubule dynamics in the growth cone provides new insights into the molecular mechanisms of axon guidance.
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Affiliation(s)
- Guofa Liu
- Department of Biological Sciences, University of Toledo, Toledo, OH, 43606, USA,
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Abstract
Malformations of cortical development are common causes of developmental delay and epilepsy. Some patients have early, severe neurological impairment, but others have epilepsy or unexpected deficits that are detectable only by screening. The rapid evolution of molecular biology, genetics, and imaging has resulted in a substantial increase in knowledge about the development of the cerebral cortex and the number and types of malformations reported. Genetic studies have identified several genes that might disrupt each of the main stages of cell proliferation and specification, neuronal migration, and late cortical organisation. Many of these malformations are caused by de-novo dominant or X-linked mutations occurring in sporadic cases. Genetic testing needs accurate assessment of imaging features, and familial distribution, if any, and can be straightforward in some disorders but requires a complex diagnostic algorithm in others. Because of substantial genotypic and phenotypic heterogeneity for most of these genes, a comprehensive analysis of clinical, imaging, and genetic data is needed to properly define these disorders. Exome sequencing and high-field MRI are rapidly modifying the classification of these disorders.
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Affiliation(s)
- Renzo Guerrini
- Department of Neuroscience, Pharmacology and Child Health, Children's Hospital A Meyer and University of Florence, Florence, Italy; Stella Maris Foundation Research Institute, Pisa, Italy.
| | - William B Dobyns
- Departments of Pediatrics and Neurology, University of Washington, Seattle, WA, USA; Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA, USA
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Fry AE, Cushion TD, Pilz DT. The genetics of lissencephaly. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2014; 166C:198-210. [DOI: 10.1002/ajmg.c.31402] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Romaniello R, Arrigoni F, Cavallini A, Tenderini E, Baschirotto C, Triulzi F, Bassi MT, Borgatti R. Brain malformations and mutations in α- and β-tubulin genes: a review of the literature and description of two new cases. Dev Med Child Neurol 2014; 56:354-60. [PMID: 24392928 DOI: 10.1111/dmcn.12370] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 11/06/2013] [Indexed: 11/29/2022]
Abstract
AIM The aim of this study was to determine the frequency of mutations in tubulin genes (TUBB2B, TUBA1A, and TUBB3) in patients with malformations of cortical development (MCDs) of unknown origin. METHOD In total, 79 out of 156 patients (41 males, 38 females; age range 8mo-55y (mean age 13y 3mo, SD 11y 2mo) with a neuroradiological diagnosis of MCDs were enrolled in the study. The 77 excluded patients were excluded for the following reasons: suspected or proven diagnosis of pre- or perinatal ischaemic insult (n=13); syndromic disease (n=10); congenital infection (n=14); pregnancy complicated by twin-to-twin transfusion syndrome (n=2); proven mutations in known genes (n=13); poor magnetic resonance imaging (MRI) quality, or lack of informed consent (n=25). A genetic analysis of the TUBA1A, TUBB2B and TUBB3 genes was carried out by direct sequencing of the coding regions of the relevant genes for each participant. Previously described patients with mutations in the TUBB2B and TUBA1A genes were reviewed; clinical and neuroradiological findings were compared and discussed. RESULTS Two novel heterozygous mutations were detected: a heterozygous mutation in exon 4 of the TUBA1A gene (c.1160C>T) in a 5-year-old female with microcephaly, severe intellectual disability, and absence of language, and a c.1080 _1084del CCTGAinsACATCTTC in exon 4 of the TUBB2B gene in a 31-year-old female with microcephaly, spastic tetraparesis, severe intellectual disability, and scoliosis. Different types of cortical abnormalities, cerebellar vermis hypoplasia, and optic nerve hypoplasia/atrophy were detected on MRI. Dysmorphisms of the basal ganglia and the hippocampi with abnormalities of the midline commissural structures were present in both cases. INTERPRETATION The consistent presence of hypoplastic and disorganized white matter tracts suggests that, in addition to defects in neuronal migration, disruption of axon growth and guidance is a peculiar feature of tubulin-related disorders.
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Affiliation(s)
- Romina Romaniello
- Neuropsychiatry and Neurorehabilitation Unit, Scientific Institute, IRCCS Eugenio Medea, Bosisio Parini, Lecco, Italy
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Breuss M, Keays DA. Microtubules and neurodevelopmental disease: the movers and the makers. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 800:75-96. [PMID: 24243101 DOI: 10.1007/978-94-007-7687-6_5] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The development of the mammalian cortex requires the generation, migration and differentiation of neurons. Each of these cellular events requires a dynamic microtubule cytoskeleton. Microtubules are required for interkinetic nuclear migration, the separation of chromatids in mitosis, nuclear translocation during migration and the outgrowth of neurites. Their importance is underlined by the finding that mutations in a host of microtubule associated proteins cause detrimental neurological disorders. More recently, the structural subunits of microtubules, the tubulin proteins, have been implicated in a spectrum of human diseases collectively known as the tubulinopathies. This chapter reviews the discovery of microtubules, the role they play in neurodevelopment, and catalogues the tubulin isoforms associated with neurodevelopmental disease. Our focus is on the molecular and cellular mechanisms that underlie the pathology of tubulin-associated diseases. Finally, we reflect on whether different tubulin genes have distinct intrinsic functions.
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Affiliation(s)
- Martin Breuss
- Institute of Molecular Pathology, Dr. Bohr-Gasse 7, 1030, Vienna, Austria
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Stottmann RW, Donlin M, Hafner A, Bernard A, Sinclair DA, Beier DR. A mutation in Tubb2b, a human polymicrogyria gene, leads to lethality and abnormal cortical development in the mouse. Hum Mol Genet 2013; 22:4053-63. [PMID: 23727838 DOI: 10.1093/hmg/ddt255] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Human cortical malformations, including lissencephaly, polymicrogyria and other diseases of neurodevelopment, have been associated with mutations in microtubule subunits and microtubule-associated proteins. Here we report our cloning of the brain dimple (brdp) mouse mutation, which we recovered from an ENU screen for recessive perinatal phenotypes affecting neurodevelopment. We identify the causal mutation in the tubulin, beta-2b (Tubb2b) gene as a missense mutation at a highly conserved residue (N247S). Brdp/brdp homozygous mutants have significant thinning of the cortical epithelium, which is markedly more severe in the caudo-lateral portion of the telencephalon, and do not survive past birth. The cortical defects are largely due to a major increase in apoptosis and we note abnormal proliferation of the basal progenitors. Adult brdp/+ mice are viable and fertile but exhibit behavioral phenotypes. This allele of Tubb2b represents the most severely affected mouse tubulin phenotype reported to date and this is the first report of a tubulin mutation affecting neuronal proliferation and survival.
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Affiliation(s)
- R W Stottmann
- Present address: Divisions of Human Genetics and Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
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Amrom D, Tanyalçin I, Verhelst H, Deconinck N, Brouhard GJ, Décarie JC, Vanderhasselt T, Das S, Hamdan FF, Lissens W, Michaud JL, Jansen AC. Polymicrogyria with dysmorphic basal ganglia? Think tubulin! Clin Genet 2013; 85:178-83. [PMID: 23495813 DOI: 10.1111/cge.12141] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2012] [Revised: 03/11/2013] [Accepted: 03/11/2013] [Indexed: 11/28/2022]
Abstract
Dominant mutations in TUBB2B have been reported in patients with polymicrogyria. We further explore the phenotype associated with mutations in TUBB2B. Twenty patients with polymicrogyria (five unilateral) were tested for mutations in TUBB2B by Sanger sequencing. We identified two novel de novo mutations, c.743C>T (p.Ala248Val) and c.1139G>T (p.Arg380Leu) in exon 4 of TUBB2B in three unrelated families. Brain magnetic resonance images showed polymicrogyria involving predominantly the perisylvian regions. In addition, there was a dysmorphic appearance of the basal ganglia, thin corpus callosum, enlargement of the ventricles, thinning of the white matter and hypoplasia of pons and cerebellar vermis. This combination of associated features was absent in all 17 patients with polymicrogyria in whom no mutation was identified. This report underlines that the association of polymicrogyria with thin or absent corpus callosum, dysmorphic basal ganglia, brainstem and vermis hypoplasia is highly likely to result from mutations in TUBB2B and provides further insight in how mutations in TUBB2B affect protein function.
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Affiliation(s)
- D Amrom
- Centre of Excellence in Neurosciences of Université de Montréal and Sainte-Justine Hospital Research Center; Neurogenetics Unit, Montreal Neurological Hospital, McGill University, Montreal, Canada
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48
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Affiliation(s)
- James Barkovich
- Department of Radiology, University of California at San Francisco, 505 Parnassus Avenue, San Francisco, CA 94143-0628, USA.
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Cushion TD, Dobyns WB, Mullins JGL, Stoodley N, Chung SK, Fry AE, Hehr U, Gunny R, Aylsworth AS, Prabhakar P, Uyanik G, Rankin J, Rees MI, Pilz DT. Overlapping cortical malformations and mutations in TUBB2B and TUBA1A. ACTA ACUST UNITED AC 2013; 136:536-48. [PMID: 23361065 DOI: 10.1093/brain/aws338] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Polymicrogyria and lissencephaly are causally heterogeneous disorders of cortical brain development, with distinct neuropathological and neuroimaging patterns. They can be associated with additional structural cerebral anomalies, and recurrent phenotypic patterns have led to identification of recognizable syndromes. The lissencephalies are usually single-gene disorders affecting neuronal migration during cerebral cortical development. Polymicrogyria has been associated with genetic and environmental causes and is considered a malformation secondary to abnormal post-migrational development. However, the aetiology in many individuals with these cortical malformations is still unknown. During the past few years, mutations in a number of neuron-specific α- and β-tubulin genes have been identified in both lissencephaly and polymicrogyria, usually associated with additional cerebral anomalies including callosal hypoplasia or agenesis, abnormal basal ganglia and cerebellar hypoplasia. The tubulin proteins form heterodimers that incorporate into microtubules, cytoskeletal structures essential for cell motility and function. In this study, we sequenced the TUBB2B and TUBA1A coding regions in 47 patients with a diagnosis of polymicrogyria and five with an atypical lissencephaly on neuroimaging. We identified four β-tubulin and two α-tubulin mutations in patients with a spectrum of cortical and extra-cortical anomalies. Dysmorphic basal ganglia with an abnormal internal capsule were the most consistent feature. One of the patients with a TUBB2B mutation had a lissencephalic phenotype, similar to that previously associated with a TUBA1A mutation. The remainder had a polymicrogyria-like cortical dysplasia, but the grey matter malformation was not typical of that seen in 'classical' polymicrogyria. We propose that the cortical malformations associated with these genes represent a recognizable tubulinopathy-associated spectrum that ranges from lissencephalic to polymicrogyric cortical dysplasias, suggesting shared pathogenic mechanisms in terms of microtubular function and interaction with microtubule-associated proteins.
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Affiliation(s)
- Thomas D Cushion
- Institute of Life Science, College of Medicine, Swansea University, Swansea SA2 8PP, UK
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Shulha HP, Crisci JL, Reshetov D, Tushir JS, Cheung I, Bharadwaj R, Chou HJ, Houston IB, Peter CJ, Mitchell AC, Yao WD, Myers RH, Chen JF, Preuss TM, Rogaev EI, Jensen JD, Weng Z, Akbarian S. Human-specific histone methylation signatures at transcription start sites in prefrontal neurons. PLoS Biol 2012; 10:e1001427. [PMID: 23185133 PMCID: PMC3502543 DOI: 10.1371/journal.pbio.1001427] [Citation(s) in RCA: 89] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2012] [Accepted: 10/12/2012] [Indexed: 11/18/2022] Open
Abstract
Cognitive abilities and disorders unique to humans are thought to result from adaptively driven changes in brain transcriptomes, but little is known about the role of cis-regulatory changes affecting transcription start sites (TSS). Here, we mapped in human, chimpanzee, and macaque prefrontal cortex the genome-wide distribution of histone H3 trimethylated at lysine 4 (H3K4me3), an epigenetic mark sharply regulated at TSS, and identified 471 sequences with human-specific enrichment or depletion. Among these were 33 loci selectively methylated in neuronal but not non-neuronal chromatin from children and adults, including TSS at DPP10 (2q14.1), CNTN4 and CHL1 (3p26.3), and other neuropsychiatric susceptibility genes. Regulatory sequences at DPP10 and additional loci carried a strong footprint of hominid adaptation, including elevated nucleotide substitution rates and regulatory motifs absent in other primates (including archaic hominins), with evidence for selective pressures during more recent evolution and adaptive fixations in modern populations. Chromosome conformation capture at two neurodevelopmental disease loci, 2q14.1 and 16p11.2, revealed higher order chromatin structures resulting in physical contact of multiple human-specific H3K4me3 peaks spaced 0.5-1 Mb apart, in conjunction with a novel cis-bound antisense RNA linked to Polycomb repressor proteins and downregulated DPP10 expression. Therefore, coordinated epigenetic regulation via newly derived TSS chromatin could play an important role in the emergence of human-specific gene expression networks in brain that contribute to cognitive functions and neurological disease susceptibility in modern day humans.
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Affiliation(s)
- Hennady P. Shulha
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Jessica L. Crisci
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Denis Reshetov
- Department of Human Genetics and Genomics, Vavilov Institute of General Genetics, Moscow, Russian Federation
| | - Jogender S. Tushir
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Iris Cheung
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Rahul Bharadwaj
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Hsin-Jung Chou
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Isaac B. Houston
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Cyril J. Peter
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Amanda C. Mitchell
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Wei-Dong Yao
- New England Primate Center, Southboro, Massachusetts, United States of America
| | - Richard H. Myers
- Department of Neurology, Boston University, Boston, Massachusetts, United States of America
| | - Jiang-fan Chen
- Department of Neurology, Boston University, Boston, Massachusetts, United States of America
| | - Todd M. Preuss
- Yerkes National Primate Research Center/Emory University, Atlanta, Georgia, United States of America
| | - Evgeny I. Rogaev
- Department of Human Genetics and Genomics, Vavilov Institute of General Genetics, Moscow, Russian Federation
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
- Research Center of Mental Health, Russian Academy of Medical Sciences, Moscow, Russian Federation
- Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Russian Federation
| | - Jeffrey D. Jensen
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
- School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Zhiping Weng
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Schahram Akbarian
- Brudnick Neuropsychiatric Research Institute, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
- Departments of Psychiatry and Neuroscience, Friedman Brain Institute, Mount Sinai School of Medicine, New York, New York, United States of America
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