1
|
Yang F, Wang M. Effect of the OPHN1 novel variant c.1025+1 G>A on RNA splicing: insights from a minigene assay. BMC Med Genomics 2024; 17:175. [PMID: 38956616 PMCID: PMC11221095 DOI: 10.1186/s12920-024-01952-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Accepted: 06/27/2024] [Indexed: 07/04/2024] Open
Abstract
This research analyzes the clinical data, whole-exome sequencing results, and in vitro minigene functional experiments of a child with developmental delay and intellectual disability. The male patient, aged 4, began experiencing epileptic seizures at 3 months post-birth and has shown developmental delay. Rehabilitation training was administered between the ages of one and two. There were no other significant family medical histories. Through comprehensive family exome genetic testing, a hemizygous variant in the 11th exon of the OPHN1 gene was identified in the affected child: c.1025 + 1G > A. Family segregation analysis confirmed the presence of this variant in the patient's mother, which had not been previously reported. According to the ACMG guidelines, this variant was classified as a likely pathogenic variant. In response to this variant, an in vitro minigene functional experiment was designed and conducted, confirming that the mutation affects the normal splicing of the gene's mRNA, resulting in a 56 bp retention on the left side of Intron 11. It was confirmed that OPHN1: c.1025 + 1G > A is the pathogenic cause of X-linked intellectual disabilities in the child, with clinical phenotypes including developmental delay and seizures.
Collapse
Affiliation(s)
- Fei Yang
- Changde Hospital, Xiangya School of Medicine, Central South University(The First People's Hospital of Changde City), No.818 Renmin Road, Changde, Hunan, 415000, China
| | - Minghui Wang
- Changde Hospital, Xiangya School of Medicine, Central South University(The First People's Hospital of Changde City), No.818 Renmin Road, Changde, Hunan, 415000, China.
| |
Collapse
|
2
|
Ohki CMY, Benazzato C, van der Linden V, França JV, Toledo CM, Machado RRG, Araujo DB, Oliveira DBL, Neris RS, Assunção-Miranda I, de Oliveira Souza IN, Nogueira CO, Leite PEC, van der Linden H, Figueiredo CP, Durigon EL, Clarke JR, Russo FB, Beltrão-Braga PCB. Zika virus infection impairs synaptogenesis, induces neuroinflammation, and could be an environmental risk factor for autism spectrum disorder outcome. Biochim Biophys Acta Mol Basis Dis 2024; 1870:167097. [PMID: 38408544 DOI: 10.1016/j.bbadis.2024.167097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 02/20/2024] [Accepted: 02/20/2024] [Indexed: 02/28/2024]
Abstract
Zika virus (ZIKV) infection was first associated with Central Nervous System (CNS) infections in Brazil in 2015, correlated with an increased number of newborns with microcephaly, which ended up characterizing the Congenital Zika Syndrome (CZS). Here, we investigated the impact of ZIKV infection on the functionality of iPSC-derived astrocytes. Besides, we extrapolated our findings to a Brazilian cohort of 136 CZS children and validated our results using a mouse model. Interestingly, ZIKV infection in neuroprogenitor cells compromises cell migration and causes apoptosis but does not interfere in astrocyte generation. Moreover, infected astrocytes lost their ability to uptake glutamate while expressing more glutamate transporters and secreted higher levels of IL-6. Besides, infected astrocytes secreted factors that impaired neuronal synaptogenesis. Since these biological endophenotypes were already related to Autism Spectrum Disorder (ASD), we extrapolated these results to a cohort of children, now 6-7 years old, and found seven children with ASD diagnosis (5.14 %). Additionally, mice infected by ZIKV revealed autistic-like behaviors, with a significant increase of IL-6 mRNA levels in the brain. Considering these evidence, we inferred that ZIKV infection during pregnancy might lead to synaptogenesis impairment and neuroinflammation, which could increase the risk for ASD.
Collapse
Affiliation(s)
| | - Cecília Benazzato
- Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | | | - Julia V França
- Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Carmen M Toledo
- Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | | | | | | | - Romulo S Neris
- Institute of Microbiology Paulo de Goes, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Iranaia Assunção-Miranda
- Institute of Microbiology Paulo de Goes, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Clara O Nogueira
- Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; School of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Paulo Emilio Corrêa Leite
- Clinical Research Unit of the Antonio Pedro Hospital, Federal Fluminense University, Rio de Janeiro, Brazil
| | | | - Claudia P Figueiredo
- Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; School of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Edison Luiz Durigon
- Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil; Institut Pasteur de São Paulo, São Paulo, Brazil
| | - Julia R Clarke
- Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; School of Pharmacy, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | | | | |
Collapse
|
3
|
Kaplow IM, Lawler AJ, Schäffer DE, Srinivasan C, Sestili HH, Wirthlin ME, Phan BN, Prasad K, Brown AR, Zhang X, Foley K, Genereux DP, Karlsson EK, Lindblad-Toh K, Meyer WK, Pfenning AR. Relating enhancer genetic variation across mammals to complex phenotypes using machine learning. Science 2023; 380:eabm7993. [PMID: 37104615 PMCID: PMC10322212 DOI: 10.1126/science.abm7993] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 02/23/2023] [Indexed: 04/29/2023]
Abstract
Protein-coding differences between species often fail to explain phenotypic diversity, suggesting the involvement of genomic elements that regulate gene expression such as enhancers. Identifying associations between enhancers and phenotypes is challenging because enhancer activity can be tissue-dependent and functionally conserved despite low sequence conservation. We developed the Tissue-Aware Conservation Inference Toolkit (TACIT) to associate candidate enhancers with species' phenotypes using predictions from machine learning models trained on specific tissues. Applying TACIT to associate motor cortex and parvalbumin-positive interneuron enhancers with neurological phenotypes revealed dozens of enhancer-phenotype associations, including brain size-associated enhancers that interact with genes implicated in microcephaly or macrocephaly. TACIT provides a foundation for identifying enhancers associated with the evolution of any convergently evolved phenotype in any large group of species with aligned genomes.
Collapse
Affiliation(s)
- Irene M. Kaplow
- Department of Computational Biology, Carnegie Mellon University, Pittsburgh, PA, USA
- Neuroscience Institute, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Alyssa J. Lawler
- Neuroscience Institute, Carnegie Mellon University, Pittsburgh, PA, USA
- Department of Biology, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Daniel E. Schäffer
- Department of Computational Biology, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Chaitanya Srinivasan
- Department of Computational Biology, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Heather H. Sestili
- Department of Computational Biology, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Morgan E. Wirthlin
- Department of Computational Biology, Carnegie Mellon University, Pittsburgh, PA, USA
- Neuroscience Institute, Carnegie Mellon University, Pittsburgh, PA, USA
| | - BaDoi N. Phan
- Department of Computational Biology, Carnegie Mellon University, Pittsburgh, PA, USA
- Neuroscience Institute, Carnegie Mellon University, Pittsburgh, PA, USA
- Medical Scientist Training Program, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Kavya Prasad
- Department of Computational Biology, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Ashley R. Brown
- Department of Computational Biology, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Xiaomeng Zhang
- Department of Computational Biology, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Kathleen Foley
- Department of Biological Sciences, Lehigh University, Bethlehem, PA, USA
| | - Diane P. Genereux
- Broad Institute, Cambridge, MA, USA
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | | | - Elinor K. Karlsson
- Broad Institute, Cambridge, MA, USA
- Program in Bioinformatics and Integrative Biology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Kerstin Lindblad-Toh
- Broad Institute, Cambridge, MA, USA
- Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Wynn K. Meyer
- Department of Biological Sciences, Lehigh University, Bethlehem, PA, USA
| | - Andreas R. Pfenning
- Department of Computational Biology, Carnegie Mellon University, Pittsburgh, PA, USA
- Neuroscience Institute, Carnegie Mellon University, Pittsburgh, PA, USA
- Department of Biology, Carnegie Mellon University, Pittsburgh, PA, USA
| |
Collapse
|
4
|
Key role of Rho GTPases in motor disorders associated with neurodevelopmental pathologies. Mol Psychiatry 2023; 28:118-126. [PMID: 35918397 DOI: 10.1038/s41380-022-01702-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 06/24/2022] [Accepted: 07/02/2022] [Indexed: 01/07/2023]
Abstract
Growing evidence suggests that Rho GTPases and molecules involved in their signaling pathways play a major role in the development of the central nervous system (CNS). Whole exome sequencing (WES) and de novo examination of mutations, including SNP (Single Nucleotide Polymorphism) in genes coding for the molecules of their signaling cascade, has allowed the recent discovery of dominant autosomic mutations and duplication or deletion of candidates in the field of neurodevelopmental diseases (NDD). Epidemiological studies show that the co-occurrence of several of these neurological pathologies may indeed be the rule. The regulators of Rho GTPases have often been considered for cognitive diseases such as intellectual disability (ID) and autism. But, in a remarkable way, mild to severe motor symptoms are now reported in autism and other cognitive NDD. Although a more abundant litterature reports the involvement of Rho GTPases and signaling partners in cognitive development, molecular investigations on their roles in central nervous system (CNS) development or degenerative CNS pathologies also reveal their role in embryonic and perinatal motor wiring through axon guidance and later in synaptic plasticity. Thus, Rho family small GTPases have been revealed to play a key role in brain functions including learning and memory but their precise role in motor development and associated symptoms in NDD has been poorly scoped so far, despite increasing clinical data highlighting the links between cognition and motor development. Indeed, early impairements in fine or gross motor performance is often an associated feature of NDDs, which then impact social communication, cognition, emotion, and behavior. We review here recent insights derived from clinical developmental neurobiology in the field of Rho GTPases and NDD (autism spectrum related disorder (ASD), ID, schizophrenia, hypotonia, spastic paraplegia, bipolar disorder and dyslexia), with a specific focus on genetic alterations affecting Rho GTPases that are involved in motor circuit development.
Collapse
|
5
|
Cresto N, Lebrun N, Dumont F, Letourneur F, Billuart P, Rouach N. Hippocampal Excitatory Synaptic Transmission and Plasticity Are Differentially Altered during Postnatal Development by Loss of the X-Linked Intellectual Disability Protein Oligophrenin-1. Cells 2022; 11:cells11091545. [PMID: 35563851 PMCID: PMC9105236 DOI: 10.3390/cells11091545] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Revised: 04/10/2022] [Accepted: 04/21/2022] [Indexed: 12/04/2022] Open
Abstract
Oligophrenin-1 (OPHN1) is a Rho-GTPase-activating protein (RhoGAP), whose mutations are associated with X-linked intellectual disability (XLID). OPHN1 is enriched at the synapse in both pre- and postsynaptic compartments, where it regulates the RhoA/ROCK/MLC2 signaling pathway, playing a critical role in cytoskeleton remodeling and vesicle recycling. Ophn1 knockout (KO) adult mice display some behavioral deficits in multiple tasks, reminiscent of some symptoms in the human pathology. We also previously reported a reduction in dendritic spine density in the adult hippocampus of KO mice. Yet the nature of the deficits occurring in these mice during postnatal development remains elusive. Here, we show that juvenile KO mice present normal basal synaptic transmission, but altered synaptic plasticity, with a selective impairment in long-term depression, but no change in long-term potentiation. This contrasts with the functional deficits that these mice display at the adult stage, as we found that both basal synaptic transmission and long-term potentiation are reduced at later stages, due to presynaptic alterations. In addition, the number of excitatory synapses in adult is increased, suggesting some unsuccessful compensation. Altogether, these results suggest that OPHN1 function at synapses is differentially affected during maturation of the brain, which provides some therapeutic opportunities for early intervention.
Collapse
Affiliation(s)
- Noemie Cresto
- Neuroglial Interactions in Cerebral Physiology and Pathologies, Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U1050, Labex Memolife, Université PSL, 75005 Paris, France;
| | - Nicolas Lebrun
- Institut de Psychiatrie et de Neurosciences de Paris, INSERM U1266, Université de Paris Cité, 75014 Paris, France;
| | - Florent Dumont
- UMS IPSIT, Université Paris-Saclay, 92296 Châtenay-Malabry, France;
| | - Franck Letourneur
- Institut Cochin, INSERM U1016, CNRS UMR8104, Université de Paris Cité, 75014 Paris, France;
| | - Pierre Billuart
- Institut de Psychiatrie et de Neurosciences de Paris, INSERM U1266, Université de Paris Cité, 75014 Paris, France;
- Correspondence: (P.B.); (N.R.)
| | - Nathalie Rouach
- Neuroglial Interactions in Cerebral Physiology and Pathologies, Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U1050, Labex Memolife, Université PSL, 75005 Paris, France;
- Correspondence: (P.B.); (N.R.)
| |
Collapse
|
6
|
A novel partial duplication in OPHN1, associated with vermis cerebellar hypoplasia, seizures and developmental delay. GENE REPORTS 2022. [DOI: 10.1016/j.genrep.2022.101590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
7
|
Kim S, Kim J, Park S, Park JJ, Lee S. Drosophila Graf regulates mushroom body β-axon extension and olfactory long-term memory. Mol Brain 2021; 14:73. [PMID: 33892766 PMCID: PMC8067379 DOI: 10.1186/s13041-021-00782-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 04/15/2021] [Indexed: 11/10/2022] Open
Abstract
Loss-of-function mutations in the human oligophrenin-1 (OPHN1) gene cause intellectual disability, a prevailing neurodevelopmental condition. However, the role OPHN1 plays during neuronal development is not well understood. We investigated the role of the Drosophila OPHN1 ortholog Graf in the development of the mushroom body (MB), a key brain structure for learning and memory in insects. We show that loss of Graf causes abnormal crossing of the MB β lobe over the brain midline during metamorphosis. This defect in Graf mutants is rescued by MB-specific expression of Graf and OPHN1. Furthermore, MB α/β neuron-specific RNA interference experiments and mosaic analyses indicate that Graf acts via a cell-autonomous mechanism. Consistent with the negative regulation of epidermal growth factor receptor (EGFR)-mitogen-activated protein kinase (MAPK) signaling by Graf, activation of this pathway is required for the β-lobe midline-crossing phenotype of Graf mutants. Finally, Graf mutants have impaired olfactory long-term memory. Our findings reveal a role for Graf in MB axon development and suggest potential neurodevelopmental functions of human OPHN1.
Collapse
Affiliation(s)
- Sungdae Kim
- Department of Cell and Developmental Biology and Dental Research Institute, Seoul National University, Seoul, 08826, Republic of Korea
| | - Joohyung Kim
- Department of Brain and Cognitive Sciences, Seoul National University, Seoul, 08826, Republic of Korea
| | - Sunyoung Park
- Department of Cell and Developmental Biology and Dental Research Institute, Seoul National University, Seoul, 08826, Republic of Korea
| | - Joong-Jean Park
- Department of Physiology, College of Medicine, Korea University, Seoul, 02841, Republic of Korea
| | - Seungbok Lee
- Department of Cell and Developmental Biology and Dental Research Institute, Seoul National University, Seoul, 08826, Republic of Korea.
| |
Collapse
|
8
|
Oligophrenin-1 moderates behavioral responses to stress by regulating parvalbumin interneuron activity in the medial prefrontal cortex. Neuron 2021; 109:1636-1656.e8. [PMID: 33831348 DOI: 10.1016/j.neuron.2021.03.016] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 02/09/2021] [Accepted: 03/10/2021] [Indexed: 12/28/2022]
Abstract
Ample evidence indicates that individuals with intellectual disability (ID) are at increased risk of developing stress-related behavioral problems and mood disorders, yet a mechanistic explanation for such a link remains largely elusive. Here, we focused on characterizing the syndromic ID gene oligophrenin-1 (OPHN1). We find that Ophn1 deficiency in mice markedly enhances helpless/depressive-like behavior in the face of repeated/uncontrollable stress. Strikingly, Ophn1 deletion exclusively in parvalbumin (PV) interneurons in the prelimbic medial prefrontal cortex (PL-mPFC) is sufficient to induce helplessness. This behavioral phenotype is mediated by a diminished excitatory drive onto Ophn1-deficient PL-mPFC PV interneurons, leading to hyperactivity in this region. Importantly, suppressing neuronal activity or RhoA/Rho-kinase signaling in the PL-mPFC reverses helpless behavior. Our results identify OPHN1 as a critical regulator of adaptive behavioral responses to stress and shed light onto the mechanistic links among OPHN1 genetic deficits, mPFC circuit dysfunction, and abnormalities in stress-related behaviors.
Collapse
|
9
|
Nuovo S, Brankovic V, Caputi C, Casella A, Nigro V, Leuzzi V, Valente EM. Novel unconventional variants expand the allelic spectrum of OPHN1 gene. Am J Med Genet A 2021; 185:1575-1581. [PMID: 33638601 DOI: 10.1002/ajmg.a.62144] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 02/01/2021] [Accepted: 02/13/2021] [Indexed: 11/08/2022]
Abstract
Mutations in the OPHN1 gene cause a rare X-linked recessive neurodevelopmental disorder characterized by intellectual disability, variably associated with cerebellar hypoplasia and distinctive facial appearance. In most of cases so far reported, the identified genomic variants involve the region encoding the central RhoGAP domain of the oligophrenin-1 protein, and are predicted to result in a complete loss of function. By using a NGS-based diagnostic approach, we identified three male and a female patients from two unrelated families carrying novel non-disruptive OPHN1 variants (the in-frame c.116_127 deletion and the missense c.2129C>T change, respectively), affecting either the BAR domain or the C-terminus proline-rich domain of the protein. Clinical and neuroimaging findings in the patients recapitulated the main features of OPHN1-related syndrome, including developmental delay, intellectual disability, behavioral disorder, dysmorphic features, seizures, cerebellar hypoplasia, and ventriculomegaly. Yet, we observed a wide variability even among affected siblings, confirming the lack of clear genotype-phenotype correlation. Our results expand the allelic spectrum of OPHN1 and illustrate the challenges for clinical interpretation of non-disruptive variants affecting X-linked genes.
Collapse
Affiliation(s)
- Sara Nuovo
- Department of Human Neuroscience, Sapienza University of Rome, Rome, Italy
| | - Vesna Brankovic
- Clinic for Child Neurology and Psychiatry, University of Belgrade, Belgrade, Serbia
| | - Caterina Caputi
- Department of Human Neuroscience, Sapienza University of Rome, Rome, Italy
| | - Antonella Casella
- Department of Molecular Medicine, University of Pavia, Pavia, Italy.,IRCCS Mondino Foundation, Pavia, Italy
| | - Vincenzo Nigro
- Department of Precision Medicine, University of Campania "Luigi Vanvitelli", Naples, Italy.,Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
| | - Vincenzo Leuzzi
- Department of Human Neuroscience, Sapienza University of Rome, Rome, Italy
| | - Enza Maria Valente
- Department of Molecular Medicine, University of Pavia, Pavia, Italy.,IRCCS Mondino Foundation, Pavia, Italy
| |
Collapse
|
10
|
Rho GTPases in the Amygdala-A Switch for Fears? Cells 2020; 9:cells9091972. [PMID: 32858950 PMCID: PMC7563696 DOI: 10.3390/cells9091972] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 08/22/2020] [Accepted: 08/25/2020] [Indexed: 12/28/2022] Open
Abstract
Fear is a fundamental evolutionary process for survival. However, excess or irrational fear hampers normal activity and leads to phobia. The amygdala is the primary brain region associated with fear learning and conditioning. There, Rho GTPases are molecular switches that act as signaling molecules for further downstream processes that modulate, among others, dendritic spine morphogenesis and thereby play a role in fear conditioning. The three main Rho GTPases—RhoA, Rac1, and Cdc42, together with their modulators, are known to be involved in many psychiatric disorders that affect the amygdala′s fear conditioning mechanism. Rich2, a RhoGAP mainly for Rac1 and Cdc42, has been studied extensively in such regard. Here, we will discuss these effectors, along with Rich2, as a molecular switch for fears, especially in the amygdala. Understanding the role of Rho GTPases in fear controlling could be beneficial for the development of therapeutic strategies targeting conditions with abnormal fear/anxiety-like behaviors.
Collapse
|
11
|
Bogliş A, Cosma AS, Tripon F, Bãnescu C. Exon 21 deletion in the OPHN1 gene in a family with syndromic X-linked intellectual disability: Case report. Medicine (Baltimore) 2020; 99:e21632. [PMID: 32872024 PMCID: PMC7437857 DOI: 10.1097/md.0000000000021632] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
INTRODUCTION The oligophrenin-1 (OPHN1) gene, localized on the X chromosome, is a Rho-GTPase activating protein that is related to syndromic X-linked intellectual disability (XLID). XLID, characterized by brain anomalies, namely cerebellar hypoplasia, specific facial features, and intellectual disability, is produced by different mutations in the OPHN1 gene. PATIENT CONCERNS In this report, we present the clinical and molecular findings of a family affected by a mild XLID due to a deletion in the OPHN1 gene, exon 21, Xq12 region using Multiplex Ligation-dependent Probe Amplification (MLPA) analysis. The clinical features present in the family are a mild developmental delay, behavioral disturbances, facial dysmorphism, pes planus, nystagmus, strabismus, epilepsy, and occipital arachnoid cyst. INTERVENTIONS The MLPA analysis was performed for investigation of the copy number variations within the X chromosome for the family. DIAGNOSIS AND OUTCOME The MLPA analysis detected a deletion in the OPHN1 gene, exon 21 for the proband, and a heterozygous deletion for the probands mother. The deletion of the Xq12 region of maternal origin, including the exon 21 of the OPHN1 gene, confirmed for the probands nephew. LESSONS Our findings emphasize the utility of the MLPA analysis to identify deletions in the OPHN1 gene responsible for syndromic XLID. Therefore, we suggest that MLPA analysis should be performed as an alternative diagnostic test for all patients with a mild intellectual disability associated or not with behavioral disturbances, facial dysmorphism, and brain anomalies.
Collapse
Affiliation(s)
- Alina Bogliş
- Laboratory of Medical Genetics, Emergency Clinical County Hospital Târgu Mureş, Târgu Mureş¸ Romania
- Department of Genetics, George Emil Palade University of Medicine, Pharmacy, Sciences, and Technology of Târgu Mureş, Târgu Mureş, Romania
- Laboratory of Molecular Biology/Genetics, Center for Advanced Medical and Pharmaceutical Research, George Emil Palade University of Medicine, Pharmacy, Sciences, and Technology of Târgu Mureş, Târgu Mureş, Romania
| | - Adriana S. Cosma
- Laboratory of Medical Genetics, Emergency Clinical County Hospital Târgu Mureş, Târgu Mureş¸ Romania
| | - Florin Tripon
- Laboratory of Medical Genetics, Emergency Clinical County Hospital Târgu Mureş, Târgu Mureş¸ Romania
- Department of Genetics, George Emil Palade University of Medicine, Pharmacy, Sciences, and Technology of Târgu Mureş, Târgu Mureş, Romania
- Laboratory of Molecular Biology/Genetics, Center for Advanced Medical and Pharmaceutical Research, George Emil Palade University of Medicine, Pharmacy, Sciences, and Technology of Târgu Mureş, Târgu Mureş, Romania
| | - Claudia Bãnescu
- Laboratory of Medical Genetics, Emergency Clinical County Hospital Târgu Mureş, Târgu Mureş¸ Romania
- Department of Genetics, George Emil Palade University of Medicine, Pharmacy, Sciences, and Technology of Târgu Mureş, Târgu Mureş, Romania
- Laboratory of Molecular Biology/Genetics, Center for Advanced Medical and Pharmaceutical Research, George Emil Palade University of Medicine, Pharmacy, Sciences, and Technology of Târgu Mureş, Târgu Mureş, Romania
| |
Collapse
|
12
|
Rho GTPase Regulators and Effectors in Autism Spectrum Disorders: Animal Models and Insights for Therapeutics. Cells 2020; 9:cells9040835. [PMID: 32244264 PMCID: PMC7226772 DOI: 10.3390/cells9040835] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 03/22/2020] [Accepted: 03/26/2020] [Indexed: 12/18/2022] Open
Abstract
The Rho family GTPases are small G proteins that act as molecular switches shuttling between active and inactive forms. Rho GTPases are regulated by two classes of regulatory proteins, guanine nucleotide exchange factors (GEFs) and GTPase-activating proteins (GAPs). Rho GTPases transduce the upstream signals to downstream effectors, thus regulating diverse cellular processes, such as growth, migration, adhesion, and differentiation. In particular, Rho GTPases play essential roles in regulating neuronal morphology and function. Recent evidence suggests that dysfunction of Rho GTPase signaling contributes substantially to the pathogenesis of autism spectrum disorder (ASD). It has been found that 20 genes encoding Rho GTPase regulators and effectors are listed as ASD risk genes by Simons foundation autism research initiative (SFARI). This review summarizes the clinical evidence, protein structure, and protein expression pattern of these 20 genes. Moreover, ASD-related behavioral phenotypes in animal models of these genes are reviewed, and the therapeutic approaches that show successful treatment effects in these animal models are discussed.
Collapse
|
13
|
Nishiyama J. Plasticity of dendritic spines: Molecular function and dysfunction in neurodevelopmental disorders. Psychiatry Clin Neurosci 2019; 73:541-550. [PMID: 31215705 DOI: 10.1111/pcn.12899] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Revised: 06/04/2019] [Accepted: 06/06/2019] [Indexed: 02/06/2023]
Abstract
Dendritic spines are tiny postsynaptic protrusions from a dendrite that receive most of the excitatory synaptic input in the brain. Functional and structural changes in dendritic spines are critical for synaptic plasticity, a cellular model of learning and memory. Conversely, altered spine morphology and plasticity are common hallmarks of human neurodevelopmental disorders, such as intellectual disability and autism. The advances in molecular and optical techniques have allowed for exploration of dynamic changes in structure and signal transduction at single-spine resolution, providing significant insights into the molecular regulation underlying spine structural plasticity. Here, I review recent findings on: how synaptic stimulation leads to diverse forms of spine structural plasticity; how the associated biochemical signals are initiated and transmitted into neuronal compartments; and how disruption of single genes associated with neurodevelopmental disorders can lead to abnormal spine structure in human and mouse brains. In particular, I discuss the functions of the Ras superfamily of small GTPases in spatiotemporal regulation of the actin cytoskeleton and protein synthesis in dendritic spines. Multiple lines of evidence implicate disrupted Ras signaling pathways in the spine structural abnormalities observed in neurodevelopmental disorders. Both deficient and excessive Ras activities lead to disrupted spine structure and deficits in learning and memory. Dysregulation of spine Ras signaling, therefore, may play a key role in the pathogenesis of multiple neurodevelopmental disorders with distinct etiologies.
Collapse
Affiliation(s)
- Jun Nishiyama
- Program in Neuroscience and Behavioral Disorders, Duke-National University of Singapore Medical School, Singapore
| |
Collapse
|
14
|
Lin JH, Tang XY, Boulling A, Zou WB, Masson E, Fichou Y, Raud L, Le Tertre M, Deng SJ, Berlivet I, Ka C, Mort M, Hayden M, Leman R, Houdayer C, Le Gac G, Cooper DN, Li ZS, Férec C, Liao Z, Chen JM. First estimate of the scale of canonical 5' splice site GT>GC variants capable of generating wild-type transcripts. Hum Mutat 2019; 40:1856-1873. [PMID: 31131953 DOI: 10.1002/humu.23821] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 04/10/2019] [Accepted: 05/24/2019] [Indexed: 12/13/2022]
Abstract
It has long been known that canonical 5' splice site (5'SS) GT>GC variants may be compatible with normal splicing. However, to date, the actual scale of canonical 5'SSs capable of generating wild-type transcripts in the case of GT>GC substitutions remains unknown. Herein, combining data derived from a meta-analysis of 45 human disease-causing 5'SS GT>GC variants and a cell culture-based full-length gene splicing assay of 103 5'SS GT>GC substitutions, we estimate that ~15-18% of canonical GT 5'SSs retain their capacity to generate between 1% and 84% normal transcripts when GT is substituted by GC. We further demonstrate that the canonical 5'SSs in which substitution of GT by GC-generated normal transcripts exhibit stronger complementarity to the 5' end of U1 snRNA than those sites whose substitutions of GT by GC did not lead to the generation of normal transcripts. We also observed a correlation between the generation of wild-type transcripts and a milder than expected clinical phenotype but found that none of the available splicing prediction tools were capable of reliably distinguishing 5'SS GT>GC variants that generated wild-type transcripts from those that did not. Our findings imply that 5'SS GT>GC variants in human disease genes may not invariably be pathogenic.
Collapse
Affiliation(s)
- Jin-Huan Lin
- EFS, Univ Brest, Inserm, UMR 1078, GGB, F-29200, Brest, France.,Department of Gastroenterology, Changhai Hospital, Second Military Medical University, Shanghai, China.,Shanghai Institute of Pancreatic Diseases, Shanghai, China
| | - Xin-Ying Tang
- Department of Gastroenterology, Changhai Hospital, Second Military Medical University, Shanghai, China.,Shanghai Institute of Pancreatic Diseases, Shanghai, China
| | - Arnaud Boulling
- EFS, Univ Brest, Inserm, UMR 1078, GGB, F-29200, Brest, France
| | - Wen-Bin Zou
- Department of Gastroenterology, Changhai Hospital, Second Military Medical University, Shanghai, China.,Shanghai Institute of Pancreatic Diseases, Shanghai, China
| | - Emmanuelle Masson
- EFS, Univ Brest, Inserm, UMR 1078, GGB, F-29200, Brest, France.,CHU Brest, Service de Génétique, Brest, France
| | - Yann Fichou
- EFS, Univ Brest, Inserm, UMR 1078, GGB, F-29200, Brest, France.,Laboratory of Excellence GR-Ex, Paris, France
| | - Loann Raud
- EFS, Univ Brest, Inserm, UMR 1078, GGB, F-29200, Brest, France
| | | | - Shun-Jiang Deng
- Department of Gastroenterology, Changhai Hospital, Second Military Medical University, Shanghai, China.,Shanghai Institute of Pancreatic Diseases, Shanghai, China
| | | | - Chandran Ka
- EFS, Univ Brest, Inserm, UMR 1078, GGB, F-29200, Brest, France.,CHU Brest, Service de Génétique, Brest, France.,Laboratory of Excellence GR-Ex, Paris, France
| | - Matthew Mort
- Institute of Medical Genetics, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Matthew Hayden
- Institute of Medical Genetics, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Raphaël Leman
- Laboratoire de Biologie et Génétique du Cancer, Centre François Baclesse, Caen, France.,Department of Genetics, F76000 and Normandy University, UNIROUEN, Inserm U1245, Normandy Centre for Genomic and Personalized Medicine, Rouen University Hospital, Rouen, France
| | - Claude Houdayer
- Department of Genetics, F76000 and Normandy University, UNIROUEN, Inserm U1245, Normandy Centre for Genomic and Personalized Medicine, Rouen University Hospital, Rouen, France
| | - Gerald Le Gac
- EFS, Univ Brest, Inserm, UMR 1078, GGB, F-29200, Brest, France.,CHU Brest, Service de Génétique, Brest, France.,Laboratory of Excellence GR-Ex, Paris, France
| | - David N Cooper
- Institute of Medical Genetics, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Zhao-Shen Li
- Department of Gastroenterology, Changhai Hospital, Second Military Medical University, Shanghai, China.,Shanghai Institute of Pancreatic Diseases, Shanghai, China
| | - Claude Férec
- EFS, Univ Brest, Inserm, UMR 1078, GGB, F-29200, Brest, France
| | - Zhuan Liao
- Department of Gastroenterology, Changhai Hospital, Second Military Medical University, Shanghai, China.,Shanghai Institute of Pancreatic Diseases, Shanghai, China
| | - Jian-Min Chen
- EFS, Univ Brest, Inserm, UMR 1078, GGB, F-29200, Brest, France
| |
Collapse
|
15
|
Schwartz TS, Wojcik MH, Pelletier RC, Edward HL, Picker JD, Holm IA, Towne MC, Beggs AH, Agrawal PB. Expanding the phenotypic spectrum associated with OPHN1 variants. Eur J Med Genet 2018; 62:137-143. [PMID: 29960046 DOI: 10.1016/j.ejmg.2018.06.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Revised: 05/02/2018] [Accepted: 06/26/2018] [Indexed: 10/28/2022]
Abstract
Genomic sequencing has allowed for the characterization of new gene-to-disease relationships, as well as the identification of variants in established disease genes in patients who do not fit the classically-described phenotype. This is especially true in rare syndromes where the clinical spectrum is not fully known. After a lengthy and costly diagnostic odyssey, patients with atypical presentations may be left with many questions even after a genetic diagnosis is identified. We present a 22-year old male with hypotonia, developmental delay, seizure disorder, and dysmorphic facial features who enrolled in our rare disease research center at 18 years of age, where exome sequencing revealed a novel, likely pathogenic variant in the OPHN1 gene. Through efforts by the study team and collaborations with the larger genetics community, contacts with other families with OPHN1 variants were eventually made, and outreach by these families expanded the patient network. This partnership between families and researchers facilitated the gathering of phenotypic information, allowing for comparison of clinical presentations among three new patients and those previously reported in the literature. These comparisons found previously unreported commonalities between the newly identified patients, such as the presence of otitis media and the lack of genitourinary abnormalities (i.e. hypoplastic scrotum, microphallus, cryptorchidism), which had been noted to be classic features of patients with OPHN1 variants. As genomic sequencing becomes more common, connecting patients with novel variants in the same gene will facilitate phenotypic analysis and continue to refine the clinical spectrum associated with that gene.
Collapse
Affiliation(s)
- Talia S Schwartz
- Division of Genetics & Genomics, Department of Medicine, Boston Children's Hospital and Harvard Medical School Boston, MA, 02115, USA; The Manton Center for Orphan Disease Research, Department of Medicine, Boston Children's Hospital and Harvard Medical School Boston, MA, 02115, USA
| | - Monica H Wojcik
- Division of Genetics & Genomics, Department of Medicine, Boston Children's Hospital and Harvard Medical School Boston, MA, 02115, USA; The Manton Center for Orphan Disease Research, Department of Medicine, Boston Children's Hospital and Harvard Medical School Boston, MA, 02115, USA; Division of Newborn Medicine, Department of Medicine, Boston Children's Hospital and Harvard Medical School Boston, MA, 02115, USA
| | - Renee C Pelletier
- Division of Genetics & Genomics, Department of Medicine, Boston Children's Hospital and Harvard Medical School Boston, MA, 02115, USA; The Manton Center for Orphan Disease Research, Department of Medicine, Boston Children's Hospital and Harvard Medical School Boston, MA, 02115, USA; Center for Cancer Risk Assessment, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
| | - Heather L Edward
- Division of Genetics & Genomics, Department of Medicine, Boston Children's Hospital and Harvard Medical School Boston, MA, 02115, USA; The Manton Center for Orphan Disease Research, Department of Medicine, Boston Children's Hospital and Harvard Medical School Boston, MA, 02115, USA; Division of Newborn Medicine, Department of Medicine, Boston Children's Hospital and Harvard Medical School Boston, MA, 02115, USA
| | - Jonathan D Picker
- Division of Genetics & Genomics, Department of Medicine, Boston Children's Hospital and Harvard Medical School Boston, MA, 02115, USA
| | - Ingrid A Holm
- Division of Genetics & Genomics, Department of Medicine, Boston Children's Hospital and Harvard Medical School Boston, MA, 02115, USA; The Manton Center for Orphan Disease Research, Department of Medicine, Boston Children's Hospital and Harvard Medical School Boston, MA, 02115, USA
| | - Meghan C Towne
- Division of Genetics & Genomics, Department of Medicine, Boston Children's Hospital and Harvard Medical School Boston, MA, 02115, USA; The Manton Center for Orphan Disease Research, Department of Medicine, Boston Children's Hospital and Harvard Medical School Boston, MA, 02115, USA; Ambry Genetics, Aliso Viejo, CA, USA
| | - Alan H Beggs
- Division of Genetics & Genomics, Department of Medicine, Boston Children's Hospital and Harvard Medical School Boston, MA, 02115, USA; The Manton Center for Orphan Disease Research, Department of Medicine, Boston Children's Hospital and Harvard Medical School Boston, MA, 02115, USA
| | - Pankaj B Agrawal
- Division of Genetics & Genomics, Department of Medicine, Boston Children's Hospital and Harvard Medical School Boston, MA, 02115, USA; The Manton Center for Orphan Disease Research, Department of Medicine, Boston Children's Hospital and Harvard Medical School Boston, MA, 02115, USA; Division of Newborn Medicine, Department of Medicine, Boston Children's Hospital and Harvard Medical School Boston, MA, 02115, USA.
| |
Collapse
|
16
|
Rho GTPases in Intellectual Disability: From Genetics to Therapeutic Opportunities. Int J Mol Sci 2018; 19:ijms19061821. [PMID: 29925821 PMCID: PMC6032284 DOI: 10.3390/ijms19061821] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 06/14/2018] [Accepted: 06/16/2018] [Indexed: 12/22/2022] Open
Abstract
Rho-class small GTPases are implicated in basic cellular processes at nearly all brain developmental steps, from neurogenesis and migration to axon guidance and synaptic plasticity. GTPases are key signal transducing enzymes that link extracellular cues to the neuronal responses required for the construction of neuronal networks, as well as for synaptic function and plasticity. Rho GTPases are highly regulated by a complex set of activating (GEFs) and inactivating (GAPs) partners, via protein:protein interactions (PPI). Misregulated RhoA, Rac1/Rac3 and cdc42 activity has been linked with intellectual disability (ID) and other neurodevelopmental conditions that comprise ID. All genetic evidences indicate that in these disorders the RhoA pathway is hyperactive while the Rac1 and cdc42 pathways are consistently hypoactive. Adopting cultured neurons for in vitro testing and specific animal models of ID for in vivo examination, the endophenotypes associated with these conditions are emerging and include altered neuronal networking, unbalanced excitation/inhibition and altered synaptic activity and plasticity. As we approach a clearer definition of these phenotype(s) and the role of hyper- and hypo-active GTPases in the construction of neuronal networks, there is an increasing possibility that selective inhibitors and activators might be designed via PPI, or identified by screening, that counteract the misregulation of small GTPases and result in alleviation of the cognitive condition. Here we review all knowledge in support of this possibility.
Collapse
|
17
|
Moortgat S, Lederer D, Deprez M, Buzatu M, Clapuyt P, Boulanger S, Benoit V, Mary S, Guichet A, Ziegler A, Colin E, Bonneau D, Maystadt I. Expanding the phenotypic spectrum associated with OPHN1 mutations: Report of 17 individuals with intellectual disability but no cerebellar hypoplasia. Eur J Med Genet 2018; 61:442-450. [PMID: 29510240 DOI: 10.1016/j.ejmg.2018.03.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Revised: 03/02/2018] [Accepted: 03/02/2018] [Indexed: 01/20/2023]
Abstract
Mutations in the oligophrenin 1 gene (OPHN1) have been identified in patients with X-linked intellectual disability (XLID) associated with cerebellar hypoplasia and ventriculomegaly, suggesting it could be a recognizable syndromic intellectual disability (ID). Affected individuals share additional clinical features including speech delay, seizures, strabismus, behavioral difficulties, and slight facial dysmorphism. OPHN1 is located in Xq12 and encodes a Rho-GTPase-activating protein involved in the regulation of the G-protein cycle. Rho protein members play an important role in dendritic growth and in plasticity of excitatory synapses. Here we report on 17 individuals from four unrelated families affected by mild to severe intellectual disability due to OPHN1 mutations without cerebellar anomaly on brain MRI. We describe clinical, genetic and neuroimaging data of affected patients. Among the identified OPHN1 mutations, we report for the first time a missense mutation occurring in a mosaic state. We discuss the intrafamilial clinical variability of the disease and compare our patients with those previously reported. We emphasize the power of next generation techniques (X-exome sequencing, whole-exome sequencing and targeted multi-gene panel) to expand the phenotypic and mutational spectrum of OPHN1-related ID.
Collapse
Affiliation(s)
- Stéphanie Moortgat
- Centre de Génétique Humaine, Institut de Pathologie et de Génétique, Charleroi, Gosselies, Belgium.
| | - Damien Lederer
- Centre de Génétique Humaine, Institut de Pathologie et de Génétique, Charleroi, Gosselies, Belgium
| | - Marie Deprez
- Centre de Génétique Humaine, Institut de Pathologie et de Génétique, Charleroi, Gosselies, Belgium; Département de Neuro-pédiatrie, Clinique Sainte-Elisabeth, Namur, Belgium
| | - Marga Buzatu
- Département de Neuro-pédiatrie, Hôpital Civil Marie Curie, Charleroi, Belgium
| | - Philippe Clapuyt
- Department of Radiology, Pediatric Imaging Unit, Cliniques Universitaires Saint-Luc, Université Catholique de Louvain, Brussels, Belgium
| | - Sébastien Boulanger
- Centre de Génétique Humaine, Institut de Pathologie et de Génétique, Charleroi, Gosselies, Belgium
| | - Valérie Benoit
- Centre de Génétique Humaine, Institut de Pathologie et de Génétique, Charleroi, Gosselies, Belgium
| | - Sandrine Mary
- Centre de Génétique Humaine, Institut de Pathologie et de Génétique, Charleroi, Gosselies, Belgium
| | - Agnès Guichet
- Department of Biochemistry and Genetics, Angers University Hospital, and UMR INSERM 1083, CNRS 6015, Angers, France
| | - Alban Ziegler
- Department of Biochemistry and Genetics, Angers University Hospital, and UMR INSERM 1083, CNRS 6015, Angers, France
| | - Estelle Colin
- Department of Biochemistry and Genetics, Angers University Hospital, and UMR INSERM 1083, CNRS 6015, Angers, France
| | - Dominique Bonneau
- Department of Biochemistry and Genetics, Angers University Hospital, and UMR INSERM 1083, CNRS 6015, Angers, France
| | - Isabelle Maystadt
- Centre de Génétique Humaine, Institut de Pathologie et de Génétique, Charleroi, Gosselies, Belgium
| |
Collapse
|
18
|
Abstract
X-linked cerebellar ataxias (XLCA) are an expanding group of genetically heterogeneous and clinically variable conditions characterized by cerebellar dysgenesis (hypoplasia, atrophy, or dysplasia) caused by gene mutations or genomic imbalances on the X chromosome. The neurologic features of XLCA include hypotonia, developmental delay, intellectual disability, ataxia, and other cerebellar signs. Normal cognitive development has also been reported. Cerebellar defects may be isolated or associated with other brain malformations or extraneurologic involvement. More than 20 genes on the X chromosome, mainly encoding for proteins involved in brain development and synaptic function that have been constantly or occasionally associated with a pathologic cerebellar phenotype, and several families with X-linked inheritance have been reported. Given the excess of males with ataxia, this group of conditions is probably underestimated and families of patients with neuroradiologic and clinical evidence of a cerebellar disorder should be counseled for high risk of X-linked inheritance.
Collapse
Affiliation(s)
- Ginevra Zanni
- Unit of Neuromuscular and Neurodegenerative Disorders, Bambino Gesu' Children's Research Hospital, Rome, Italy.
| | - Enrico Bertini
- Unit of Neuromuscular and Neurodegenerative Disorders, Bambino Gesu' Children's Research Hospital, Rome, Italy
| |
Collapse
|
19
|
Abstract
During the process of neurogenesis, the stem cell committed to the neuronal cell fate starts a series of molecular and morphological changes. The understanding of the physio-pathology of mechanisms controlling the molecular and morphological changes occurring during neuronal differentiation is fundamental to the development of effective therapies for many neurologic diseases. Unfortunately, our knowledge of the biological events occurring in the cell during neuronal differentiation is still poor. In this study, we focus preliminarily on the relevance of the cytoskeletal rearrangements, which earlier drive the morphology of the neuronal precursors, and later the migrating/mature neurons. In fact, neuritogenesis, neurite branching, outgrowth and retraction are seminal to the development of a fully functional nervous system. With this in mind, we highlight the importance of iPSC technology to study the processes of cytoskeletal-driven morphological changes during neuronal differentiation.
Collapse
|
20
|
Guo W, Cai Y, Zhang H, Yang Y, Yang G, Wang X, Zhao J, Lin J, Zhu J, Li W, Lv L. Association of ARHGAP18 polymorphisms with schizophrenia in the Chinese-Han population. PLoS One 2017; 12:e0175209. [PMID: 28384650 PMCID: PMC5383423 DOI: 10.1371/journal.pone.0175209] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 03/22/2017] [Indexed: 11/23/2022] Open
Abstract
Numerous developmental genes have been linked to schizophrenia (SZ) by case-control and genome-wide association studies, suggesting that neurodevelopmental disturbances are major pathogenic mechanisms. However, no neurodevelopmental deficit has been definitively linked to SZ occurrence, likely due to disease heterogeneity and the differential effects of various gene variants across ethnicities. Hence, it is critical to examine linkages in specific ethnic populations, such as Han Chinese. The newly identified RhoGAP ARHGAP18 is likely involved in neurodevelopment through regulation of RhoA/C. Here we describe four single nucleotide polymorphisms (SNPs) in ARHGAP18 associated with SZ across a cohort of >2000 cases and controls from the Han population. Two SNPs, rs7758025 and rs9483050, displayed significant differences between case and control groups both in genotype (P = 0.0002 and P = 7.54×10−6) and allelic frequencies (P = 4.36×10−5 and P = 5.98×10−7), respectively. The AG haplotype in rs7758025−rs9385502 was strongly associated with the occurrence of SZ (P = 0.0012, OR = 0.67, 95% CI = 0.48–0.93), an association that still held following a 1000-times random permutation test (P = 0.022). In an independently collected validation cohort, rs9483050 was the SNP most strongly associated with SZ. In addition, the allelic frequencies of rs12197901 remained associated with SZ in the combined cohort (P = 0.021), although not in the validation cohort alone (P = 0.251). Collectively, our data suggest the ARHGAP18 may confer vulnerability to SZ in the Chinese Han population, providing additional evidence for the involvement of neurodevelopmental dysfunction in the pathogenesis of schizophrenia.
Collapse
Affiliation(s)
- Weiyun Guo
- College of Life Science and Technology, Xinxiang Medical University, Xinxiang, China.,Henan Key Lab of Biological Psychiatry, Xinxiang Medical University, Xinxiang, China
| | - Yaqi Cai
- Henan Key Lab of Biological Psychiatry, Xinxiang Medical University, Xinxiang, China.,Department of Psychiatry, Henan Mental Hospital, The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang, China
| | - Hongxing Zhang
- Henan Key Lab of Biological Psychiatry, Xinxiang Medical University, Xinxiang, China.,Department of Psychiatry, Henan Mental Hospital, The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang, China.,Department of Psychology, Xinxiang Medical University, Xinxiang, China
| | - Yongfeng Yang
- Henan Key Lab of Biological Psychiatry, Xinxiang Medical University, Xinxiang, China.,Department of Psychiatry, Henan Mental Hospital, The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang, China
| | - Ge Yang
- Henan Key Lab of Biological Psychiatry, Xinxiang Medical University, Xinxiang, China.,Department of Psychiatry, Henan Mental Hospital, The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang, China
| | - Xiujuan Wang
- Henan Key Lab of Biological Psychiatry, Xinxiang Medical University, Xinxiang, China.,Department of Psychiatry, Henan Mental Hospital, The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang, China
| | - Jingyuan Zhao
- Department of Psychiatry, Henan Mental Hospital, The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang, China
| | - Juntang Lin
- College of Life Science and Technology, Xinxiang Medical University, Xinxiang, China.,Henan Key Lab of Biological Psychiatry, Xinxiang Medical University, Xinxiang, China.,Institute of Anatomy I, Friedrich Schiller University Jena, Jena, Germany
| | - Jinfu Zhu
- Institute of Anatomy I, Friedrich Schiller University Jena, Jena, Germany.,Department of Psychology, Xinxiang Medical University, Xinxiang, China
| | - Wenqiang Li
- Henan Key Lab of Biological Psychiatry, Xinxiang Medical University, Xinxiang, China.,Department of Psychiatry, Henan Mental Hospital, The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang, China
| | - Luxian Lv
- Henan Key Lab of Biological Psychiatry, Xinxiang Medical University, Xinxiang, China.,Department of Psychiatry, Henan Mental Hospital, The Second Affiliated Hospital of Xinxiang Medical University, Xinxiang, China
| |
Collapse
|
21
|
Role of a circadian-relevant gene NR1D1 in brain development: possible involvement in the pathophysiology of autism spectrum disorders. Sci Rep 2017; 7:43945. [PMID: 28262759 PMCID: PMC5338261 DOI: 10.1038/srep43945] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 01/31/2017] [Indexed: 02/07/2023] Open
Abstract
In our previous study, we screened autism spectrum disorder (ASD) patients with and without sleep disorders for mutations in the coding regions of circadian-relevant genes, and detected mutations in several clock genes including NR1D1. Here, we further screened ASD patients for NR1D1 mutations and identified three novel mutations including a de novo heterozygous one c.1499 G > A (p.R500H). We then analyzed the role of Nr1d1 in the development of the cerebral cortex in mice. Acute knockdown of mouse Nr1d1 with in utero electroporation caused abnormal positioning of cortical neurons during corticogenesis. This aberrant phenotype was rescued by wild type Nr1d1, but not by the c.1499 G > A mutant. Time-lapse imaging revealed characteristic abnormal migration phenotypes in Nr1d1-deficient cortical neurons. When Nr1d1 was knocked down, axon extension and dendritic arbor formation of cortical neurons were also suppressed while proliferation of neuronal progenitors and stem cells at the ventricular zone was not affected. Taken together, Nr1d1 was found to play a pivotal role in corticogenesis via regulation of excitatory neuron migration and synaptic network formation. These results suggest that functional defects in NR1D1 may be related to ASD etiology and pathophysiology.
Collapse
|
22
|
Large in-frame intragenic deletion of OPHN1 in a male patient with a normal intelligence quotient score. Clin Dysmorphol 2017; 26:47-49. [PMID: 27390894 DOI: 10.1097/mcd.0000000000000139] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
|
23
|
Huang GH, Sun ZL, Li HJ, Feng DF. Rho GTPase-activating proteins: Regulators of Rho GTPase activity in neuronal development and CNS diseases. Mol Cell Neurosci 2017; 80:18-31. [PMID: 28163190 DOI: 10.1016/j.mcn.2017.01.007] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Revised: 01/06/2017] [Accepted: 01/29/2017] [Indexed: 12/22/2022] Open
Abstract
The Rho family of small GTPases was considered as molecular switches in regulating multiple cellular events, including cytoskeleton reorganization. The Rho GTPase-activating proteins (RhoGAPs) are one of the major families of Rho GTPase regulators. RhoGAPs were initially considered negative mediators of Rho signaling pathways via their GAP domain. Recent studies have demonstrated that RhoGAPs also regulate numerous aspects of neuronal development and are related to various neurodegenerative diseases in GAP-dependent and GAP-independent manners. Moreover, RhoGAPs are regulated through various mechanisms, such as phosphorylation. To date, approximately 70 RhoGAPs have been identified; however, only a small portion has been thoroughly investigated. Thus, the characterization of important RhoGAPs in the central nervous system is crucial to understand their spatiotemporal role during different stages of neuronal development. In this review, we summarize the current knowledge of RhoGAPs in the brain with an emphasis on their molecular function, regulation mechanism and disease implications in the central nervous system.
Collapse
Affiliation(s)
- Guo-Hui Huang
- Department of Neurosurgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201900, China
| | - Zhao-Liang Sun
- Department of Neurosurgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201900, China
| | - Hong-Jiang Li
- Department of Neurosurgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201900, China
| | - Dong-Fu Feng
- Department of Neurosurgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201900, China; Institute of Traumatic Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai 201900, China.
| |
Collapse
|
24
|
Compagnucci C, Barresi S, Petrini S, Billuart P, Piccini G, Chiurazzi P, Alfieri P, Bertini E, Zanni G. Rho Kinase Inhibition Is Essential During In Vitro Neurogenesis and Promotes Phenotypic Rescue of Human Induced Pluripotent Stem Cell-Derived Neurons With Oligophrenin-1 Loss of Function. Stem Cells Transl Med 2016; 5:860-9. [PMID: 27160703 DOI: 10.5966/sctm.2015-0303] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Accepted: 02/23/2016] [Indexed: 01/02/2023] Open
Abstract
UNLABELLED : Rho-GTPases have relevant functions in various aspects of neuronal development, such as differentiation, migration, and synaptogenesis. Loss of function of the oligophrenin-1 gene (OPHN1) causes X-linked intellectual disability with cerebellar hypoplasia and leads to hyperactivation of the rho kinase (ROCK) pathway. ROCK mainly acts through phosphorylation of the myosin phosphatase targeting subunit 1, triggering actin-myosin contractility. We show that during in vitro neurogenesis, ROCK activity decreases from day 10 until terminal differentiation, whereas in OPHN1-deficient human induced pluripotent stem cells (h-iPSCs), the levels of ROCK are elevated throughout differentiation. ROCK inhibition favors neuronal-like appearance of h-iPSCs, in parallel with transcriptional upregulation of nuclear receptor NR4A1, which is known to induce neurite outgrowth. This study analyzed the morphological, biochemical, and functional features of OPHN1-deficient h-iPSCs and their rescue by treatment with the ROCK inhibitor fasudil, shedding light on the relevance of the ROCK pathway during neuronal differentiation and providing a neuronal model for human OPHN1 syndrome and its treatment. SIGNIFICANCE The analysis of the levels of rho kinase (ROCK) activity at different stages of in vitro neurogenesis of human induced pluripotent stem cells reveals that ROCK activity decreases progressively in parallel with the appearance of neuronal-like morphology and upregulation of nuclear receptor NR4A1. These results shed light on the role of the ROCK pathway during early stages of human neurogenesis and provide a neuronal stem cell-based model for the treatment of OPHN1 syndrome and other neurological disorders due to ROCK dysfunction.
Collapse
Affiliation(s)
- Claudia Compagnucci
- Unit of Neuromuscular and Neurodegenerative Disorders, Department of Neurosciences, Bambino Gesù Children's Hospital, Istituti di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Sabina Barresi
- Unit of Neuromuscular and Neurodegenerative Disorders, Department of Neurosciences, Bambino Gesù Children's Hospital, Istituti di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Stefania Petrini
- Research Laboratories, Confocal Microscopy Core Facility, and Bambino Gesù Children's Hospital, Istituti di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Pierre Billuart
- Department of Genetic and Development, Institut Cochin, Université Paris Descartes, Paris, France
| | - Giorgia Piccini
- Unit of Child Neuropsychiatry, Department of Neurosciences, Bambino Gesù Children's Hospital, Istituti di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Pietro Chiurazzi
- Institute of Human and Medical Genetics, Catholic University, Rome, Italy
| | - Paolo Alfieri
- Unit of Child Neuropsychiatry, Department of Neurosciences, Bambino Gesù Children's Hospital, Istituti di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Enrico Bertini
- Unit of Neuromuscular and Neurodegenerative Disorders, Department of Neurosciences, Bambino Gesù Children's Hospital, Istituti di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| | - Ginevra Zanni
- Unit of Neuromuscular and Neurodegenerative Disorders, Department of Neurosciences, Bambino Gesù Children's Hospital, Istituti di Ricovero e Cura a Carattere Scientifico, Rome, Italy
| |
Collapse
|
25
|
Meziane H, Khelfaoui M, Morello N, Hiba B, Calcagno E, Reibel-Foisset S, Selloum M, Chelly J, Humeau Y, Riet F, Zanni G, Herault Y, Bienvenu T, Giustetto M, Billuart P. Fasudil treatment in adult reverses behavioural changes and brain ventricular enlargement in Oligophrenin-1 mouse model of intellectual disability. Hum Mol Genet 2016; 25:2314-2323. [PMID: 27146843 DOI: 10.1093/hmg/ddw102] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Accepted: 03/17/2016] [Indexed: 01/09/2023] Open
Abstract
Loss of function mutations in human Oligophrenin1 (OPHN1) gene are responsible for syndromic intellectual disability (ID) associated with cerebellar hypoplasia and cerebral ventricles enlargement. Functional studies in rodent models suggest that OPHN1 linked ID is a consequence of abnormal synaptic transmission and shares common pathophysiological mechanisms with other cognitive disorders. Variants of this gene have been also identified in autism spectrum disorder and schizophrenia. The advanced understanding of the mechanisms underlying OPHN1-related ID, allowed us to develop a therapeutic approach targeting the Ras homolog gene family, member A (RHOA) signalling pathway and repurpose Fasudil- a well-tolerated Rho Kinase (ROCK) and Protein Kinase A (PKA) inhibitor- as a treatment of ID. We have previously shown ex-vivo its beneficial effect on synaptic transmission and plasticity in a mouse model of the OPHN1 loss of function. Here, we report that chronic treatment in adult mouse with Fasudil, is able to counteract vertical and horizontal hyperactivities, restores recognition memory and limits the brain ventricular dilatation observed in Ophn1-/y However, deficits in working and spatial memories are partially or not rescued by the treatment. These results highlight the potential of Fasudil treatment in synaptopathies and also the need for multiple therapeutic approaches especially in adult where brain plasticity is reduced.
Collapse
Affiliation(s)
- Hamid Meziane
- PHENOMIN, Institut Clinique de la Souris, ICS; GIE CERBM, Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS, UMR7104, INSERM, U964, University of Strasbourg, F-67404 Illkirch-Graffenstaden, France
| | - Malik Khelfaoui
- Institut Cochin, INSERM U1016, CNRS UMR8104, Paris Descartes University, Paris, 75014, France Institut interdisciplinaire de neuroscience, CNRS UMR5297, University of Bordeaux, Bordeaux, 33077, France
| | - Noemi Morello
- University of Torino, Department of Neuroscience « Rita Levi Montalcini », National Institute of Neuroscience-Italy, Torino, 10126, Italy
| | - Bassem Hiba
- Centre de Résonance Magnétique des Systèmes Biologiques, UMR 5536 CNRS, Université de Bordeaux, 33077, Bordeaux, France
| | - Eleonora Calcagno
- University of Torino, Department of Neuroscience « Rita Levi Montalcini », National Institute of Neuroscience-Italy, Torino, 10126, Italy
| | | | - Mohammed Selloum
- PHENOMIN, Institut Clinique de la Souris, ICS; GIE CERBM, Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS, UMR7104, INSERM, U964, University of Strasbourg, F-67404 Illkirch-Graffenstaden, France
| | - Jamel Chelly
- PHENOMIN, Institut Clinique de la Souris, ICS; GIE CERBM, Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS, UMR7104, INSERM, U964, University of Strasbourg, F-67404 Illkirch-Graffenstaden, France Institut Cochin, INSERM U1016, CNRS UMR8104, Paris Descartes University, Paris, 75014, France
| | - Yann Humeau
- Institut interdisciplinaire de neuroscience, CNRS UMR5297, University of Bordeaux, Bordeaux, 33077, France
| | - Fabrice Riet
- PHENOMIN, Institut Clinique de la Souris, ICS; GIE CERBM, Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS, UMR7104, INSERM, U964, University of Strasbourg, F-67404 Illkirch-Graffenstaden, France
| | - Ginevra Zanni
- Department of Neurosciences, Laboratory of Molecular Medicine, Unit of Neuromuscular and Neurodegenerative Disorders, Bambino Gesù Children's Hospital, IRCCS, 00165, Rome, Italy
| | - Yann Herault
- PHENOMIN, Institut Clinique de la Souris, ICS; GIE CERBM, Institut de Génétique et de Biologie Moléculaire et Cellulaire, CNRS, UMR7104, INSERM, U964, University of Strasbourg, F-67404 Illkirch-Graffenstaden, France
| | - Thierry Bienvenu
- Institut Cochin, INSERM U1016, CNRS UMR8104, Paris Descartes University, Paris, 75014, France
| | - Maurizio Giustetto
- University of Torino, Department of Neuroscience « Rita Levi Montalcini », National Institute of Neuroscience-Italy, Torino, 10126, Italy
| | - Pierre Billuart
- Institut Cochin, INSERM U1016, CNRS UMR8104, Paris Descartes University, Paris, 75014, France
| |
Collapse
|
26
|
Temporal lobe in human aging: A quantitative protein profiling study of samples from Chinese Human Brain Bank. Exp Gerontol 2015; 73:31-41. [PMID: 26631761 DOI: 10.1016/j.exger.2015.11.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 11/24/2015] [Accepted: 11/25/2015] [Indexed: 01/25/2023]
Abstract
The temporal lobe is a portion of the cerebral cortex with critical functionality. The age-related protein profile changes in the human temporal lobe have not been previously studied. This 4-plex tandem mass tag labeled proteomic study was performed on samples of temporal lobe from Chinese donors. Tissue samples were assigned to four age groups: Group A (the young, age: 34±13 years); Group B (the elderly, 62±5 years); Group C (the aged, 84±4 years) and Group D (the old, 95±1 years). Pooled samples from the different groups were subjected to proteomics and bioinformatics analysis to identify age-related changes in protein expression and associated pathways. We isolated 5072 proteins, and found that 67 proteins were downregulated and 109 proteins were upregulated in one or more groups during the aging process. Western blotting assays were performed to verify the proteomic results. Bioinformatic analysis identified proteins involved in neuronal degeneration, including proteins involved in neuronal firing, myelin sheath damage, and cell structure stability. We also observed the accumulation of extracellular matrix and lysosomal proteins which imply the occurrence of fibrosis and autophagy. Our results suggest a series of changes across a wide range of proteins in the human temporal lobe that may relate to aging and age-related neurodegenerative disorders.
Collapse
|
27
|
Kumar R, Corbett MA, Van Bon BWM, Gardner A, Woenig JA, Jolly LA, Douglas E, Friend K, Tan C, Van Esch H, Holvoet M, Raynaud M, Field M, Leffler M, Budny B, Wisniewska M, Badura-Stronka M, Latos-Bieleńska A, Batanian J, Rosenfeld JA, Basel-Vanagaite L, Jensen C, Bienek M, Froyen G, Ullmann R, Hu H, Love MI, Haas SA, Stankiewicz P, Cheung SW, Baxendale A, Nicholl J, Thompson EM, Haan E, Kalscheuer VM, Gecz J. Increased STAG2 dosage defines a novel cohesinopathy with intellectual disability and behavioral problems. Hum Mol Genet 2015; 24:7171-81. [PMID: 26443594 DOI: 10.1093/hmg/ddv414] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Accepted: 09/28/2015] [Indexed: 11/13/2022] Open
Abstract
Next generation genomic technologies have made a significant contribution to the understanding of the genetic architecture of human neurodevelopmental disorders. Copy number variants (CNVs) play an important role in the genetics of intellectual disability (ID). For many CNVs, and copy number gains in particular, the responsible dosage-sensitive gene(s) have been hard to identify. We have collected 18 different interstitial microduplications and 1 microtriplication of Xq25. There were 15 affected individuals from 6 different families and 13 singleton cases, 28 affected males in total. The critical overlapping region involved the STAG2 gene, which codes for a subunit of the cohesin complex that regulates cohesion of sister chromatids and gene transcription. We demonstrate that STAG2 is the dosage-sensitive gene within these CNVs, as gains of STAG2 mRNA and protein dysregulate disease-relevant neuronal gene networks in cells derived from affected individuals. We also show that STAG2 gains result in increased expression of OPHN1, a known X-chromosome ID gene. Overall, we define a novel cohesinopathy due to copy number gain of Xq25 and STAG2 in particular.
Collapse
Affiliation(s)
- Raman Kumar
- School of Medicine, and the Robinson Research Institute, The University of Adelaide, Adelaide, SA 5000, Australia
| | - Mark A Corbett
- School of Medicine, and the Robinson Research Institute, The University of Adelaide, Adelaide, SA 5000, Australia
| | | | - Alison Gardner
- School of Medicine, and the Robinson Research Institute, The University of Adelaide, Adelaide, SA 5000, Australia
| | - Joshua A Woenig
- School of Medicine, and the Robinson Research Institute, The University of Adelaide, Adelaide, SA 5000, Australia
| | - Lachlan A Jolly
- School of Medicine, and the Robinson Research Institute, The University of Adelaide, Adelaide, SA 5000, Australia
| | - Evelyn Douglas
- Genetics and Molecular Pathology, SA Pathology, North Adelaide, SA 5006, Australia
| | - Kathryn Friend
- Genetics and Molecular Pathology, SA Pathology, North Adelaide, SA 5006, Australia
| | - Chuan Tan
- School of Medicine, and the Robinson Research Institute, The University of Adelaide, Adelaide, SA 5000, Australia
| | - Hilde Van Esch
- Center for Human Genetics, University Hospitals Leuven, 3000 Leuven, Belgium
| | - Maureen Holvoet
- Center for Human Genetics, University Hospitals Leuven, 3000 Leuven, Belgium
| | - Martine Raynaud
- Centre Hospitalier Régional Universitaire, Service de Génétique, 37000 Tours, France
| | - Michael Field
- Genetics of Learning Disability Service, Hunter Genetics, Waratah, NSW 2298, Australia
| | - Melanie Leffler
- Genetics of Learning Disability Service, Hunter Genetics, Waratah, NSW 2298, Australia
| | - Bartłomiej Budny
- Department of Endocrinology, Metabolism and Internal Diseases and
| | - Marzena Wisniewska
- Department of Medical Genetics, Poznan University of Medical Sciences, Poznan 60-355, Poland
| | | | - Anna Latos-Bieleńska
- Department of Medical Genetics, Poznan University of Medical Sciences, Poznan 60-355, Poland
| | | | - Jill A Rosenfeld
- Signature Genomic Laboratories, Spokane, WA 99207, USA, Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Lina Basel-Vanagaite
- Raphael Recanati Genetic Institute and Felsenstein Medical Research Center, Rabin Medical Center, Beilinson Campus, Petah Tikva 49100, Israel
| | | | | | - Guy Froyen
- Human Genome Laboratory, Department of Human Genetics, KU Leuven, 3000 Leuven, Belgium and
| | - Reinhard Ullmann
- Department of Human Molecular Genetics and, Bundeswehr Institute of Radiobiology, 80937 Munich, Germany
| | - Hao Hu
- Department of Human Molecular Genetics and
| | - Michael I Love
- Department of Computational Molecular Biology, Max Planck Institute for Molecular Genetics, Ihnestrasse 73, 14195 Berlin, Germany
| | - Stefan A Haas
- Department of Computational Molecular Biology, Max Planck Institute for Molecular Genetics, Ihnestrasse 73, 14195 Berlin, Germany
| | - Pawel Stankiewicz
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Sau Wai Cheung
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Anne Baxendale
- South Australian Clinical Genetics Service, SA Pathology, North Adelaide, SA 5006, Australia
| | - Jillian Nicholl
- Genetics and Molecular Pathology, SA Pathology, North Adelaide, SA 5006, Australia
| | - Elizabeth M Thompson
- School of Medicine, and the Robinson Research Institute, The University of Adelaide, Adelaide, SA 5000, Australia, South Australian Clinical Genetics Service, SA Pathology, North Adelaide, SA 5006, Australia
| | - Eric Haan
- School of Medicine, and the Robinson Research Institute, The University of Adelaide, Adelaide, SA 5000, Australia, South Australian Clinical Genetics Service, SA Pathology, North Adelaide, SA 5006, Australia
| | | | - Jozef Gecz
- School of Medicine, and the Robinson Research Institute, The University of Adelaide, Adelaide, SA 5000, Australia,
| |
Collapse
|
28
|
Compagnucci C, Barresi S, Petrini S, Bertini E, Zanni G. Rho-kinase signaling controls nucleocytoplasmic shuttling of class IIa histone deacetylase (HDAC7) and transcriptional activation of orphan nuclear receptor NR4A1. Biochem Biophys Res Commun 2014; 459:179-183. [PMID: 25511694 DOI: 10.1016/j.bbrc.2014.12.033] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Accepted: 12/08/2014] [Indexed: 12/20/2022]
Abstract
Rho-kinase (ROCK) has been well documented to play a key role in RhoA-induced actin remodeling. ROCK activation results in myosin light chain (MLC) phosphorylation either by direct action on MLC kinase (MLCK) or by inhibition of MLC phosphatase (MLCP), modulating actin-myosin contraction. We found that inhibition of the ROCK pathway in induced pluripotent stem cells, leads to nuclear export of HDAC7 and transcriptional activation of the orphan nuclear receptor NR4A1 while in cells with constitutive ROCK hyperactivity due to loss of function of the RhoGTPase activating protein Oligophrenin-1 (OPHN1), the orphan nuclear receptor NR4A1 is downregulated. Our study identify a new target of ROCK signaling via myosin phosphatase subunit (MYPT1) and Histone Deacetylase (HDAC7) at the nuclear level and provide new insights in the cellular functions of ROCK.
Collapse
Affiliation(s)
- Claudia Compagnucci
- Unit of Molecular Medicine for Neuromuscular and Neurodegenerative Disorders, Department of Neurosciences, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Sabina Barresi
- Unit of Molecular Medicine for Neuromuscular and Neurodegenerative Disorders, Department of Neurosciences, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Stefania Petrini
- Research Laboratories, Confocal Microscopy Core Facility, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Enrico Bertini
- Unit of Molecular Medicine for Neuromuscular and Neurodegenerative Disorders, Department of Neurosciences, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Ginevra Zanni
- Unit of Molecular Medicine for Neuromuscular and Neurodegenerative Disorders, Department of Neurosciences, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy.
| |
Collapse
|
29
|
Mulherkar S, Uddin MD, Couvillon AD, Sillitoe RV, Tolias KF. The small GTPases RhoA and Rac1 regulate cerebellar development by controlling cell morphogenesis, migration and foliation. Dev Biol 2014; 394:39-53. [PMID: 25128586 DOI: 10.1016/j.ydbio.2014.08.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 08/06/2014] [Indexed: 12/22/2022]
Abstract
The small GTPases RhoA and Rac1 are key cytoskeletal regulators that function in a mutually antagonistic manner to control the migration and morphogenesis of a broad range of cell types. However, their role in shaping the cerebellum, a unique brain structure composed of an elaborate set of folia separated by fissures of different lengths, remains largely unexplored. Here we show that dysregulation of both RhoA and Rac1 signaling results in abnormal cerebellar ontogenesis. Ablation of RhoA from neuroprogenitor cells drastically alters the timing and placement of fissure formation, the migration and positioning of granule and Purkinje cells, the alignment of Bergmann glia, and the integrity of the basement membrane, primarily in the anterior lobules. Furthermore, in the absence of RhoA, granule cell precursors located at the base of fissures fail to undergo cell shape changes required for fissure initiation. Many of these abnormalities can be recapitulated by deleting RhoA specifically from granule cell precursors but not postnatal glia, indicating that RhoA functions in granule cell precursors to control cerebellar morphogenesis. Notably, mice with elevated Rac1 activity due to loss of the Rac1 inhibitors Bcr and Abr show similar anterior cerebellar deficits, including ectopic neurons and defects in fissure formation, Bergmann glia organization and basement membrane integrity. Together, our results suggest that RhoA and Rac1 play indispensable roles in patterning cerebellar morphology.
Collapse
Affiliation(s)
- Shalaka Mulherkar
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | | | - Anthony D Couvillon
- Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Roy V Sillitoe
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children׳s Hospital, Houston, TX 77030, USA; Department of Pathology & Immunology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Kimberley F Tolias
- Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA; Verna and Marrs McLean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, One Baylor Plaza, M.S. BCM 295, Houston, TX 77030, USA.
| |
Collapse
|
30
|
Mignon-Ravix C, Cacciagli P, Choucair N, Popovici C, Missirian C, Milh M, Mégarbané A, Busa T, Julia S, Girard N, Badens C, Sigaudy S, Philip N, Villard L. Intragenic rearrangements in X-linked intellectual deficiency: results of a-CGH in a series of 54 patients and identification of TRPC5 and KLHL15 as potential XLID genes. Am J Med Genet A 2014; 164A:1991-7. [PMID: 24817631 DOI: 10.1002/ajmg.a.36602] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 04/03/2014] [Indexed: 01/24/2023]
Abstract
High-resolution array comparative genomic hybridization (a-CGH) enables the detection of intragenic rearrangements, such as single exon deletion or duplication. This approach can lead to the identification of new disease genes. We report on the analysis of 54 male patients presenting with intellectual deficiency (ID) and a family history suggesting X-linked (XL) inheritance or maternal skewed X-chromosome inactivation (XCI), using a home-made X-chromosome-specific microarray covering the whole human X-chromosome at high resolution. The majority of patients had whole genome array-CGH prior to the selection and we did not include large rearrangements such as MECP2 and FMR1 duplications. We identified four rearrangements considered as causative or potentially pathogenic, corresponding to a detection rate of 8%. Two CNVs affected known XLID genes and were therefore considered as causative (IL1RAPL1 and OPHN1 intragenic deletions). Two new CNVs were considered as potentially pathogenic as they affected interesting candidates for ID. The first CNV is a deletion of the first exon of the TRPC5 gene, encoding a cation channel implicated in dendrite growth and patterning, in a child presenting with ID and an autism spectrum disorder (ASD). The second CNV is a partial deletion of KLHL15, in a patient with severe ID, epilepsy, and anomalies of cortical development. In both cases, in spite of strong arguments for clinical relevance, we were not able at this stage to confirm pathogenicity of the mutations, and the causality of the variants identified in XLID remains to be confirmed.
Collapse
Affiliation(s)
- Cécile Mignon-Ravix
- Inserm, UMR_S 910, Marseille, France; Aix Marseille Université, GMGF, Marseille, France
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
31
|
Barresi S, Tomaselli S, Athanasiadis A, Galeano F, Locatelli F, Bertini E, Zanni G, Gallo A. Oligophrenin-1 (OPHN1), a gene involved in X-linked intellectual disability, undergoes RNA editing and alternative splicing during human brain development. PLoS One 2014; 9:e91351. [PMID: 24637888 PMCID: PMC3956665 DOI: 10.1371/journal.pone.0091351] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Accepted: 02/11/2014] [Indexed: 12/25/2022] Open
Abstract
Oligophrenin-1 (OPHN1) encodes for a Rho-GTPase-activating protein, important for dendritic morphogenesis and synaptic function. Mutations in this gene have been identified in patients with X-linked intellectual disability associated with cerebellar hypoplasia. ADAR enzymes are responsible for A-to-I RNA editing, an essential post-transcriptional RNA modification contributing to transcriptome and proteome diversification. Specifically, ADAR2 activity is essential for brain development and function. Herein, we show that the OPHN1 transcript undergoes post-transcriptional modifications such as A-to-I RNA editing and alternative splicing in human brain and other tissues. We found that OPHN1 editing is detectable already at the 18th week of gestation in human brain with a boost of editing at weeks 20 to 33, concomitantly with OPHN1 expression increase and the appearance of a novel OPHN1 splicing isoform. Our results demonstrate that multiple post-transcriptional events occur on OPHN1, a gene playing an important role in brain function and development.
Collapse
Affiliation(s)
- Sabina Barresi
- Molecular Medicine Laboratory, Neurosciences Department, Bambino Gesù Children's Hospital IRCCS, Rome, Italy
| | - Sara Tomaselli
- RNA Editing Laboratory, Oncohaematology Department, Bambino Gesù Children's Hospital IRCCS, Rome, Italy
| | | | - Federica Galeano
- RNA Editing Laboratory, Oncohaematology Department, Bambino Gesù Children's Hospital IRCCS, Rome, Italy
| | - Franco Locatelli
- RNA Editing Laboratory, Oncohaematology Department, Bambino Gesù Children's Hospital IRCCS, Rome, Italy
- Università di Pavia, Pavia, Italy
| | - Enrico Bertini
- Molecular Medicine Laboratory, Neurosciences Department, Bambino Gesù Children's Hospital IRCCS, Rome, Italy
| | - Ginevra Zanni
- Molecular Medicine Laboratory, Neurosciences Department, Bambino Gesù Children's Hospital IRCCS, Rome, Italy
- * E-mail: (GZ); (AG)
| | - Angela Gallo
- RNA Editing Laboratory, Oncohaematology Department, Bambino Gesù Children's Hospital IRCCS, Rome, Italy
- * E-mail: (GZ); (AG)
| |
Collapse
|
32
|
Khelfaoui M, Gambino F, Houbaert X, Ragazzon B, Müller C, Carta M, Lanore F, Srikumar BN, Gastrein P, Lepleux M, Zhang CL, Kneib M, Poulain B, Reibel-Foisset S, Vitale N, Chelly J, Billuart P, Lüthi A, Humeau Y. Lack of the presynaptic RhoGAP protein oligophrenin1 leads to cognitive disabilities through dysregulation of the cAMP/PKA signalling pathway. Philos Trans R Soc Lond B Biol Sci 2013; 369:20130160. [PMID: 24298161 DOI: 10.1098/rstb.2013.0160] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Loss-of-function mutations in the gene encoding for the RhoGAP protein of oligophrenin-1 (OPHN1) lead to cognitive disabilities (CDs) in humans, yet the underlying mechanisms are not known. Here, we show that in mice constitutive lack of Ophn1 is associated with dysregulation of the cyclic adenosine monophosphate/phosphate kinase A (cAMP/PKA) signalling pathway in a brain-area-specific manner. Consistent with a key role of cAMP/PKA signalling in regulating presynaptic function and plasticity, we found that PKA-dependent presynaptic plasticity was completely abolished in affected brain regions, including hippocampus and amygdala. At the behavioural level, lack of OPHN1 resulted in hippocampus- and amygdala-related learning disabilities which could be fully rescued by the ROCK/PKA kinase inhibitor fasudil. Together, our data identify OPHN1 as a key regulator of presynaptic function and suggest that, in addition to reported postsynaptic deficits, loss of presynaptic plasticity contributes to the pathophysiology of CDs.
Collapse
Affiliation(s)
- Malik Khelfaoui
- Centre National de la Recherche Scientifique UPR3212, CNRS, Université de Strasbourg, , Strasbourg 67084, France
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
33
|
A novel in-frame deletion affecting the BAR domain of OPHN1 in a family with intellectual disability and hippocampal alterations. Eur J Hum Genet 2013; 22:644-51. [PMID: 24105372 DOI: 10.1038/ejhg.2013.216] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Revised: 08/12/2013] [Accepted: 08/16/2013] [Indexed: 12/13/2022] Open
Abstract
Oligophrenin-1 (OPHN1) is one of at least seven genes located on chromosome X that take part in Rho GTPase-dependent signaling pathways involved in X-linked intellectual disability (XLID). Mutations in OPHN1 were primarily described as an exclusive cause of non-syndromic XLID, but the re-evaluation of the affected individuals using brain imaging displayed fronto-temporal atrophy and cerebellar hypoplasia as neuroanatomical marks. In this study, we describe clinical, genetic and neuroimaging data of a three generation Brazilian XLID family co-segregating a novel intragenic deletion in OPHN1. This deletion results in an in-frame loss of exon 7 at transcription level (c.781_891del; r.487_597del), which is predicted to abolish 37 amino acids from the highly conserved N-terminal BAR domain of OPHN1. cDNA expression analysis demonstrated that the mutant OPHN1 transcript is stable and no abnormal splicing was observed. Features shared by the affected males of this family include neonatal hypotonia, strabismus, prominent root of the nose, deep set eyes, hyperactivity and instability/intolerance to frustration. Cranial MRI scans showed large lateral ventricles, vermis hypoplasia and cystic dilatation of the cisterna magna in all affected males. Interestingly, hippocampal alterations that have not been reported in patients with loss-of-function OPHN1 mutations were found in three affected individuals, suggesting an important function for the BAR domain in the hippocampus. This is the first description of an in-frame deletion within the BAR domain of OPHN1 and could provide new insights into the role of this domain in relation to brain and cognitive development or function.
Collapse
|
34
|
Ba W, van der Raadt J, Nadif Kasri N. Rho GTPase signaling at the synapse: implications for intellectual disability. Exp Cell Res 2013; 319:2368-74. [PMID: 23769912 DOI: 10.1016/j.yexcr.2013.05.033] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2013] [Accepted: 05/29/2013] [Indexed: 12/18/2022]
Abstract
Intellectual disability (ID) imposes a major medical and social-economical problem in our society. It is defined as a global reduction in cognitive and intellectual abilities, associated with impaired social adaptation. The causes of ID are extremely heterogeneous and include non-genetic and genetic changes. Great progress has been made over recent years towards the identification of ID-related genes, resulting in a list of approximately 450 genes. A prominent neuropathological feature of patients with ID is altered dendritic spine morphogenesis. These structural abnormalities, in part, reflect impaired cytoskeleton remodeling and are associated with synaptic dysfunction. The dynamic, actin-rich nature of dendritic spines points to the Rho GTPase family as a central contributor, since they are key regulators of actin dynamics and organization. It is therefore not surprising that mutations in genes encoding regulators and effectors of the Rho GTPases have been associated with ID. This review will focus on the role of Rho GTPase signaling in synaptic structure/function and ID.
Collapse
Affiliation(s)
- Wei Ba
- Donders Institute for Brain Cognition and Behavior, Radboud University Nijmegen Medical Center, Department Cognitive Neuroscience, the Netherlands
| | | | | |
Collapse
|
35
|
Di Gregorio E, Bianchi FT, Schiavi A, Chiotto AMA, Rolando M, Verdun di Cantogno L, Grosso E, Cavalieri S, Calcia A, Lacerenza D, Zuffardi O, Retta SF, Stevanin G, Marelli C, Durr A, Forlani S, Chelly J, Montarolo F, Tempia F, Beggs HE, Reed R, Squadrone S, Abete MC, Brussino A, Ventura N, Di Cunto F, Brusco A. A de novo X;8 translocation creates a PTK2-THOC2 gene fusion with THOC2 expression knockdown in a patient with psychomotor retardation and congenital cerebellar hypoplasia. J Med Genet 2013; 50:543-51. [PMID: 23749989 DOI: 10.1136/jmedgenet-2013-101542] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
BACKGROUND AND AIM We identified a balanced de novo translocation involving chromosomes Xq25 and 8q24 in an eight year-old girl with a non-progressive form of congenital ataxia, cognitive impairment and cerebellar hypoplasia. METHODS AND RESULTS Breakpoint definition showed that the promoter of the Protein Tyrosine Kinase 2 (PTK2, also known as Focal Adhesion Kinase, FAK) gene on chromosome 8q24.3 is translocated 2 kb upstream of the THO complex subunit 2 (THOC2) gene on chromosome Xq25. PTK2 is a well-known non-receptor tyrosine kinase whereas THOC2 encodes a component of the evolutionarily conserved multiprotein THO complex, involved in mRNA export from nucleus. The translocation generated a sterile fusion transcript under the control of the PTK2 promoter, affecting expression of both PTK2 and THOC2 genes. PTK2 is involved in cell adhesion and, in neurons, plays a role in axonal guidance, and neurite growth and attraction. However, PTK2 haploinsufficiency alone is unlikely to be associated with human disease. Therefore, we studied the role of THOC2 in the CNS using three models: 1) THOC2 ortholog knockout in C.elegans which produced functional defects in specific sensory neurons; 2) Thoc2 knockdown in primary rat hippocampal neurons which increased neurite extension; 3) Thoc2 knockdown in neuronal stem cells (LC1) which increased their in vitro growth rate without modifying apoptosis levels. CONCLUSION We suggest that THOC2 can play specific roles in neuronal cells and, possibly in combination with PTK2 reduction, may affect normal neural network formation, leading to cognitive impairment and cerebellar congenital hypoplasia.
Collapse
|
36
|
Vedolin L, Gonzalez G, Souza CF, Lourenço C, Barkovich AJ. Inherited cerebellar ataxia in childhood: a pattern-recognition approach using brain MRI. AJNR Am J Neuroradiol 2013; 34:925-34, S1-2. [PMID: 22595899 PMCID: PMC7964648 DOI: 10.3174/ajnr.a3055] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Ataxia is the principal symptom of many common neurologic diseases in childhood. Ataxias caused by dysfunction of the cerebellum occur in acute, intermittent, and progressive disorders. Most of the chronic progressive processes are secondary to degenerative and metabolic diseases. In addition, congenital malformation of the midbrain and hindbrain can also be present, with posterior fossa symptoms related to ataxia. Brain MR imaging is the most accurate imaging technique to investigate these patients, and imaging abnormalities include size, shape, and/or signal of the brain stem and/or cerebellum. Supratentorial and cord lesions are also common. This review will discuss a pattern-recognition approach to inherited cerebellar ataxia in childhood. The purpose is to provide a comprehensive discussion that ultimately could help neuroradiologists better manage this important topic in pediatric neurology.
Collapse
Affiliation(s)
- L Vedolin
- Neuroradiology Section, Hospital Moinhos de Vento, Porto Alegre, Brazil.
| | | | | | | | | |
Collapse
|
37
|
Midbrain and hindbrain malformations: advances in clinical diagnosis, imaging, and genetics. Lancet Neurol 2013; 12:381-93. [PMID: 23518331 DOI: 10.1016/s1474-4422(13)70024-3] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Historically, the midbrain and hindbrain have been considered of secondary importance to the cerebrum, which has typically been acknowledged as the most important part of the brain. In the past, radiologists and pathologists did not regularly examine these structures-also known as the brainstem and cerebellum-because they are small and difficult to remove without damage. With recent developments in neuroimaging, neuropathology, and neurogenetics, many developmental disorders of the midbrain and hindbrain have emerged as causes of neurodevelopmental dysfunction. These research advances may change the way in which we treat these patients in the future and will enhance the clinical acumen of the practising neurologist and thereby improve the diagnosis and treatment of these patients.
Collapse
|
38
|
Mutation of plasma membrane Ca2+ ATPase isoform 3 in a family with X-linked congenital cerebellar ataxia impairs Ca2+ homeostasis. Proc Natl Acad Sci U S A 2012; 109:14514-9. [PMID: 22912398 DOI: 10.1073/pnas.1207488109] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Ca(2+) in neurons is vital to processes such as neurotransmission, neurotoxicity, synaptic development, and gene expression. Disruption of Ca(2+) homeostasis occurs in brain aging and in neurodegenerative disorders. Membrane transporters, among them the calmodulin (CaM)-activated plasma membrane Ca(2+) ATPases (PMCAs) that extrude Ca(2+) from the cell, play a key role in neuronal Ca(2+) homeostasis. Using X-exome sequencing we have identified a missense mutation (G1107D) in the CaM-binding domain of isoform 3 of the PMCAs in a family with X-linked congenital cerebellar ataxia. PMCA3 is highly expressed in the cerebellum, particularly in the presynaptic terminals of parallel fibers-Purkinje neurons. To study the effects of the mutation on Ca(2+) extrusion by the pump, model cells (HeLa) were cotransfected with expression plasmids encoding its mutant or wild-type (wt) variants and with the Ca(2+)-sensing probe aequorin. The mutation reduced the ability of the PMCA3 pump to control the cellular homeostasis of Ca(2+). It significantly slowed the return to baseline of the Ca(2+) transient induced by an inositol-trisphosphate (InsP(3))-linked plasma membrane agonist. It also compromised the ability of the pump to oppose the influx of Ca(2+) through the plasma membrane capacitative channels.
Collapse
|
39
|
Abstract
Genetic causes of intellectual disability (ID) include mutations in proteins with various functions. However, many of these proteins are enriched in synapses and recent investigations point out their crucial role in the subtle regulation of synaptic activity and dendritic spine morphogenesis. Moreover, in addition to genetic data, functional and animal model studies are providing compelling evidence that supports the emerging unifying synapse-based theory for cognitive deficit. In this review, we highlight ID-related gene products involved in synaptic morphogenesis and function, with a particular focus on the emergent signaling pathways involved in synaptic plasticity whose disruption results in cognitive deficit.
Collapse
|
40
|
Abstract
The cytoskeleton forms the backbone of neuronal architecture, sustaining its form and size, subcellular compartments and cargo logistics. The synaptic cytoskeleton can be categorized in the microtubule-based core cytoskeleton and the cortical membrane skeleton. While central microtubules form the fundamental basis for the construction of elaborate neuronal processes, including axons and synapses, cortical actin filaments are generally considered to function as mediators of synapse dynamics and plasticity. More recently, the submembranous network of spectrin and ankyrin molecules has been involved in the regulation of synaptic stability and maintenance. Disruption of the synaptic cytoskeleton primarily affects the stability and maturation of synapses but also secondarily disturbs neuronal communication. Consequently, a variety of inherited diseases are accompanied by cytoskeletal malfunctions, including spastic paraplegias, spinocerebellar ataxias, and mental retardation. Since the primary reasons for many of these diseases are still unknown model organisms with a conserved repertoire of cytoskeletal elements help to understand the underlying biological mechanisms. The astonishing technical as well as genetic accessibility of synapses in Drosophila has shown that loss of the cytoskeletal architecture leads to axonal transport defects, synaptic maturation deficits, and retraction of synaptic boutons, before synaptic terminals finally detach from their target cells, suggesting that similar processes could be involved in human neuronal diseases.
Collapse
Affiliation(s)
- Bernd Goellner
- Heinrich-Heine-University Düsseldorf, Functional Cell Morphology Lab, Düsseldorf, Germany
| | | |
Collapse
|
41
|
Ligeti E, Welti S, Scheffzek K. Inhibition and Termination of Physiological Responses by GTPase Activating Proteins. Physiol Rev 2012; 92:237-72. [DOI: 10.1152/physrev.00045.2010] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Physiological processes are strictly organized in space and time. However, in cell physiology research, more attention is given to the question of space rather than to time. To function as a signal, environmental changes must be restricted in time; they need not only be initiated but also terminated. In this review, we concentrate on the role of one specific protein family involved in biological signal termination. GTPase activating proteins (GAPs) accelerate the endogenously low GTP hydrolysis rate of monomeric guanine nucleotide-binding proteins (GNBPs), limiting thereby their prevalence in the active, GTP-bound form. We discuss cases where defective or excessive GAP activity of specific proteins causes significant alteration in the function of the nervous, endocrine, and hemopoietic systems, or contributes to development of infections and tumors. Biochemical and genetic data as well as observations from human pathology support the notion that GAPs represent vital elements in the spatiotemporal fine tuning of physiological processes.
Collapse
Affiliation(s)
- Erzsébet Ligeti
- Department of Physiology, Semmelweis University, Budapest, Hungary; Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany; and Division of Biological Chemistry, Biocenter, Innsbruck Medical University, Innsbruck, Austria
| | - Stefan Welti
- Department of Physiology, Semmelweis University, Budapest, Hungary; Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany; and Division of Biological Chemistry, Biocenter, Innsbruck Medical University, Innsbruck, Austria
| | - Klaus Scheffzek
- Department of Physiology, Semmelweis University, Budapest, Hungary; Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany; and Division of Biological Chemistry, Biocenter, Innsbruck Medical University, Innsbruck, Austria
| |
Collapse
|
42
|
Nadif Kasri N, Nakano-Kobayashi A, Van Aelst L. Rapid synthesis of the X-linked mental retardation protein OPHN1 mediates mGluR-dependent LTD through interaction with the endocytic machinery. Neuron 2011; 72:300-15. [PMID: 22017989 DOI: 10.1016/j.neuron.2011.09.001] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/01/2011] [Indexed: 01/12/2023]
Abstract
VIDEO ABSTRACT Activation of group I metabotropic glutamate receptors leads to long-term depression (mGluR-LTD). Alterations in this form of plasticity have been linked to drug addiction and cognitive disorders. A key characteristic of mGluR-LTD is its dependence on rapid protein synthesis; however, the identities of the proteins mediating LTD remain elusive. Here, we identify the X-linked mental retardation protein OPHN1 as a molecule essential for mGluR-LTD in the hippocampus. mGluR-LTD induction elicits rapid dendritic OPHN1 synthesis, which is dependent on mGluR1 activation and independent of fragile X mental retardation protein (FMRP). This response is essential for mGluR-LTD, as acute blockade of OPHN1 synthesis impedes LTD. mGluR-induced OPHN1 mediates LTD and associated persistent decreases in surface AMPARs via interactions with endophilin A2/3. Importantly, this role of OPHN1 is separable from its effects on basal synaptic strength, which require OPHN1's Rho-GAP activity and interaction with Homer1b/c. Thus, our data establish a role for rapid OPHN1 synthesis in mGluR-LTD.
Collapse
Affiliation(s)
- Nael Nadif Kasri
- Cold Spring Harbor Laboratory, 1 Bungtown Road, Cold Spring Harbor, New York 11724, USA
| | | | | |
Collapse
|
43
|
Bertholdo D, de Carvalho Neto A, Castillo M. Posterior fossa malformation associated with cerebral anomalies: genetic and imaging features. Top Magn Reson Imaging 2011; 22:295-302. [PMID: 24132068 DOI: 10.1097/rmr.0b013e3182a2cca0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Many posterior fossa malformations are associated with other malformations particularly supratentorial ones, which tend to affect the prognosis of these patients. The role of the cerebellum in higher learning is just beginning to be understood, but it is obvious that cerebellar abnormalities may result in higher-cognition defects. Studies have demonstrated cerebellar abnormalities in patients with developmental encephalopathies, such as autism, mental retardation, and Rett syndrome. Disorders that affect cell life cycles and result in abnormal cell proliferation and abnormal cell migration disorders (hemimegalencephaly, dystroglicanopathy, lissencephaly, and gray matter heterotopia) can also be accompanied by posterior fossa malformations. In this article, we discuss hindbrain-midbrain malformations associated with developmental encephalopathies and with supratentorial brain abnormalities that result from abnormal cell proliferation and cell migration.
Collapse
Affiliation(s)
- Débora Bertholdo
- From the *Clínica Diagnóstico Avançado por Imagem, Curitiba; †Universidade Federal do Paraná, Curitiba, PR, Brazil; and ‡University of North Carolina, Chapel Hill, NC
| | | | | |
Collapse
|
44
|
Gallant NM, Baldwin E, Salamon N, Dipple KM, Quintero-Rivera F. Pontocerebellar hypoplasia in association with de novo 19p13.11p13.12 microdeletion. Am J Med Genet A 2011; 155A:2871-8. [PMID: 21994138 DOI: 10.1002/ajmg.a.34286] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2011] [Accepted: 08/04/2011] [Indexed: 02/04/2023]
Abstract
The pontocerebellar hypoplasias (PCHs) are a group of clinically variable disorders characterized by abnormally small cerebellum and brainstem, generally inherited in an autosomal recessive pattern. While PCHs have been grouped into six subtypes, clinical diagnosis is equivocal until a genetic diagnosis is established. We report a patient with PCH, intrauterine growth restriction, ventricular septal defect, rib anomalies, midgut malrotation, and facial dysmorphic features. Using SNP analysis, we identified three de novo deletions of: 1.055 Mb at 6q24.3q25.1 (148174730-149229583); 169 kb at 16p13.2 (6565411-6733934); and 2.530 Mb at 19p13.11p13.12 (13857587-16387798), which were confirmed by FISH. 19p13 deletions are rare aberrations. Of patients previously described with overlapping 19p13.12 deletions and multiple anomalies, only one presented with PCH. Deleted in both that patient and the patient reported here, is DDX39, a DEAD-box RNA helicase. DDX39 is part of the homeostatic machinery that regulates the switch of cellular proliferation and differentiation. It is highly expressed in the developing central nervous system and optic cup of Xenopus laevis. The brain abnormalities in the patient reported here were more severe than the previously reported patient, which may be due to additional deletions or undetected point mutations in the nondeleted allele. Notably, the patient reported here also has a partial deletion of RBFOX1 (A2BP1), which lies within the autism susceptibility locus on 16p13.2. Our findings suggest chromosomal microarray analysis may be useful in determining etiology of syndromic PCH.
Collapse
MESH Headings
- Abnormalities, Multiple/diagnosis
- Abnormalities, Multiple/genetics
- Chromosome Deletion
- Chromosomes, Human, Pair 16/genetics
- Chromosomes, Human, Pair 19/genetics
- Chromosomes, Human, Pair 6/genetics
- DEAD-box RNA Helicases/genetics
- Fatal Outcome
- Female
- Humans
- In Situ Hybridization, Fluorescence
- Infant
- Infant, Newborn
- Magnetic Resonance Imaging
- Olivopontocerebellar Atrophies/diagnosis
- Olivopontocerebellar Atrophies/genetics
- Olivopontocerebellar Atrophies/pathology
- Point Mutation
- Polymorphism, Single Nucleotide
- Pregnancy
- Pregnancy Complications/pathology
- RNA Splicing Factors
- RNA-Binding Proteins/genetics
Collapse
Affiliation(s)
- Natalie M Gallant
- Departments of Pediatrics and Human Genetics, David Geffen School of Medicine at UCLA, Los Angeles, California, USA
| | | | | | | | | |
Collapse
|
45
|
Pirozzi F, Di Raimo FR, Zanni G, Bertini E, Billuart P, Tartaglione T, Tabolacci E, Brancaccio A, Neri G, Chiurazzi P. Insertion of 16 amino acids in the BAR domain of the oligophrenin 1 protein causes mental retardation and cerebellar hypoplasia in an Italian family. Hum Mutat 2011; 32:E2294-307. [PMID: 21796728 DOI: 10.1002/humu.21567] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2010] [Accepted: 07/07/2011] [Indexed: 11/10/2022]
Abstract
We observed a three-generation family with two maternal cousins and an uncle affected by mental retardation (MR) with cerebellar hypoplasia. X-linked inheritance and the presence of cerebellar malformation suggested a mutation in the OPHN1 gene. In fact, mutational screening revealed a 2-bp deletion that abolishes a donor splicing site, resulting in the inclusion of the initial 48 nucleotides of intron 7 in the mRNA. This mutation determines the production of a mutant oligophrenin 1 protein with 16 extra amino acids inserted in-frame in the N-terminal BAR (Bin1/amphiphysin/Rvs167) domain. This is the first case of a mutation in OPHN1 that does not result in the production of a truncated protein or in its complete loss. OPHN1 (ARHGAP41) encodes a GTPase-activating (GAP) protein belonging to the GRAF subfamily characterized by an N-terminal BAR domain, followed by a pleckstrin-homology (PH) domain and the GAP domain. GRAF proteins play a role in endocytosis and are supposed to dimerize via their BAR domain, that induces membrane curvature. The extra 16 amino acids cause the insertion of 4.4 turns in the third alpha-helix of the BAR domain and apparently impair the protein function. In fact, the clinical phenotype of these patients is identical to that of patients with loss-of-function mutations.
Collapse
|
46
|
Celestino-Soper PBS, Shaw CA, Sanders SJ, Li J, Murtha MT, Ercan-Sencicek AG, Davis L, Thomson S, Gambin T, Chinault AC, Ou Z, German JR, Milosavljevic A, Sutcliffe JS, Cook EH, Stankiewicz P, State MW, Beaudet AL. Use of array CGH to detect exonic copy number variants throughout the genome in autism families detects a novel deletion in TMLHE. Hum Mol Genet 2011; 20:4360-70. [PMID: 21865298 DOI: 10.1093/hmg/ddr363] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Autism is a neurodevelopmental disorder with increasing evidence of heterogeneous genetic etiology including de novo and inherited copy number variants (CNVs). We performed array comparative genomic hybridization using a custom Agilent 1 M oligonucleotide array intended to cover 197 332 unique exons in RefSeq genes; 98% were covered by at least one probe and 95% were covered by three or more probes with the focus on detecting relatively small CNVs that would implicate a single protein-coding gene. The study group included 99 trios from the Simons Simplex Collection. The analysis identified and validated 55 potentially pathogenic CNVs, categorized as de novo autosomal heterozygous, inherited homozygous autosomal, complex autosomal and hemizygous deletions on the X chromosome of probands. Twenty percent (11 of 55) of these CNV calls were rare when compared with the Database of Genomic Variants. Thirty-six percent (20 of 55) of the CNVs were also detected in the same samples in an independent analysis using the 1 M Illumina single-nucleotide polymorphism array. Findings of note included a common and sometimes homozygous 61 bp exonic deletion in SLC38A10, three CNVs found in lymphoblast-derived DNA but not present in whole-blood derived DNA and, most importantly, in a male proband, an exonic deletion of the TMLHE (trimethyllysine hydroxylase epsilon) that encodes the first enzyme in the biosynthesis of carnitine. Data for CNVs present in lymphoblasts but absent in fresh blood DNA suggest that these represent clonal outgrowth of individual B cells with pre-existing somatic mutations rather than artifacts arising in cell culture. GEO accession number GSE23765 (http://www.ncbi.nlm.nih.gov/geo/, date last accessed on 30 August 2011). Genboree accession: http://genboree.org/java-bin/gbrowser.jsp?refSeqId=1868&entryPointId=chr17&from=53496072&to=53694382&isPublic=yes, date last accessed on 30 August 2011.
Collapse
|
47
|
Piton A, Gauthier J, Hamdan FF, Lafrenière RG, Yang Y, Henrion E, Laurent S, Noreau A, Thibodeau P, Karemera L, Spiegelman D, Kuku F, Duguay J, Destroismaisons L, Jolivet P, Côté M, Lachapelle K, Diallo O, Raymond A, Marineau C, Champagne N, Xiong L, Gaspar C, Rivière JB, Tarabeux J, Cossette P, Krebs MO, Rapoport JL, Addington A, DeLisi LE, Mottron L, Joober R, Fombonne E, Drapeau P, Rouleau GA. Systematic resequencing of X-chromosome synaptic genes in autism spectrum disorder and schizophrenia. Mol Psychiatry 2011; 16:867-80. [PMID: 20479760 PMCID: PMC3289139 DOI: 10.1038/mp.2010.54] [Citation(s) in RCA: 221] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2009] [Revised: 04/10/2010] [Accepted: 04/12/2010] [Indexed: 12/17/2022]
Abstract
Autism spectrum disorder (ASD) and schizophrenia (SCZ) are two common neurodevelopmental syndromes that result from the combined effects of environmental and genetic factors. We set out to test the hypothesis that rare variants in many different genes, including de novo variants, could predispose to these conditions in a fraction of cases. In addition, for both disorders, males are either more significantly or more severely affected than females, which may be explained in part by X-linked genetic factors. Therefore, we directly sequenced 111 X-linked synaptic genes in individuals with ASD (n = 142; 122 males and 20 females) or SCZ (n = 143; 95 males and 48 females). We identified >200 non-synonymous variants, with an excess of rare damaging variants, which suggest the presence of disease-causing mutations. Truncating mutations in genes encoding the calcium-related protein IL1RAPL1 (already described in Piton et al. Hum Mol Genet 2008) and the monoamine degradation enzyme monoamine oxidase B were found in ASD and SCZ, respectively. Moreover, several promising non-synonymous rare variants were identified in genes encoding proteins involved in regulation of neurite outgrowth and other various synaptic functions (MECP2, TM4SF2/TSPAN7, PPP1R3F, PSMD10, MCF2, SLITRK2, GPRASP2, and OPHN1).
Collapse
Affiliation(s)
- A Piton
- Department of Medicine, Centre of Excellence in Neuromics, CHUM Research Centre, University of Montreal, Montreal, QC, Canada
| | - J Gauthier
- Department of Medicine, Centre of Excellence in Neuromics, CHUM Research Centre, University of Montreal, Montreal, QC, Canada
| | - FF Hamdan
- CHU Sainte-Justine Research Center, Montreal, QC, Canada
| | - RG Lafrenière
- Department of Medicine, Centre of Excellence in Neuromics, CHUM Research Centre, University of Montreal, Montreal, QC, Canada
| | - Y Yang
- Department of Medicine, Centre of Excellence in Neuromics, CHUM Research Centre, University of Montreal, Montreal, QC, Canada
| | - E Henrion
- Department of Medicine, Centre of Excellence in Neuromics, CHUM Research Centre, University of Montreal, Montreal, QC, Canada
| | - S Laurent
- Department of Medicine, Centre of Excellence in Neuromics, CHUM Research Centre, University of Montreal, Montreal, QC, Canada
| | - A Noreau
- Department of Medicine, Centre of Excellence in Neuromics, CHUM Research Centre, University of Montreal, Montreal, QC, Canada
| | - P Thibodeau
- Department of Medicine, Centre of Excellence in Neuromics, CHUM Research Centre, University of Montreal, Montreal, QC, Canada
| | - L Karemera
- Department of Medicine, Centre of Excellence in Neuromics, CHUM Research Centre, University of Montreal, Montreal, QC, Canada
| | - D Spiegelman
- Department of Medicine, Centre of Excellence in Neuromics, CHUM Research Centre, University of Montreal, Montreal, QC, Canada
| | - F Kuku
- Department of Medicine, Centre of Excellence in Neuromics, CHUM Research Centre, University of Montreal, Montreal, QC, Canada
| | - J Duguay
- Department of Medicine, Centre of Excellence in Neuromics, CHUM Research Centre, University of Montreal, Montreal, QC, Canada
| | - L Destroismaisons
- Department of Medicine, Centre of Excellence in Neuromics, CHUM Research Centre, University of Montreal, Montreal, QC, Canada
| | - P Jolivet
- Department of Medicine, Centre of Excellence in Neuromics, CHUM Research Centre, University of Montreal, Montreal, QC, Canada
| | - M Côté
- Department of Medicine, Centre of Excellence in Neuromics, CHUM Research Centre, University of Montreal, Montreal, QC, Canada
| | - K Lachapelle
- Department of Medicine, Centre of Excellence in Neuromics, CHUM Research Centre, University of Montreal, Montreal, QC, Canada
| | - O Diallo
- Department of Medicine, Centre of Excellence in Neuromics, CHUM Research Centre, University of Montreal, Montreal, QC, Canada
| | - A Raymond
- Department of Medicine, Centre of Excellence in Neuromics, CHUM Research Centre, University of Montreal, Montreal, QC, Canada
| | - C Marineau
- Department of Medicine, Centre of Excellence in Neuromics, CHUM Research Centre, University of Montreal, Montreal, QC, Canada
| | - N Champagne
- Department of Pathology and Cell Biology and Groupe de recherche sur le systeme nerveux central, University of Montreal, Montreal, QC, Canada
| | - L Xiong
- Department of Medicine, Centre of Excellence in Neuromics, CHUM Research Centre, University of Montreal, Montreal, QC, Canada
| | - C Gaspar
- Department of Medicine, Centre of Excellence in Neuromics, CHUM Research Centre, University of Montreal, Montreal, QC, Canada
| | - J-B Rivière
- Department of Medicine, Centre of Excellence in Neuromics, CHUM Research Centre, University of Montreal, Montreal, QC, Canada
| | - J Tarabeux
- Department of Medicine, Centre of Excellence in Neuromics, CHUM Research Centre, University of Montreal, Montreal, QC, Canada
| | - P Cossette
- Department of Medicine, Centre of Excellence in Neuromics, CHUM Research Centre, University of Montreal, Montreal, QC, Canada
| | - M-O Krebs
- INSERM U796, Physiopathologie des maladies psychiatriques, Université Paris Descartes and Centre hospitalier Sainte Anne, Paris, France
| | - JL Rapoport
- Child Psychiatry Branch, NIMH/NIH, Bethesda, MD, USA
| | - A Addington
- Child Psychiatry Branch, NIMH/NIH, Bethesda, MD, USA
| | - LE DeLisi
- VA Boston Healthcare System and Harvard Medical School, Brockton, MA, USA
- The Department of Psychiatry, New York University Langone Medical Center, New York, NY, USA
| | - L Mottron
- Centre d’excellence en Troubles envahissants du développement de l’Université de Montré al (CETEDUM), Montreal, QC, Canada
| | - R Joober
- Department of Psychiatry, Douglas Mental Health University Institute, McGill University, Montreal, QC, Canada
| | - E Fombonne
- Department of Psychiatry, Montreal Children’s Hospital, Montreal, QC, Canada
| | - P Drapeau
- Department of Pathology and Cell Biology and Groupe de recherche sur le systeme nerveux central, University of Montreal, Montreal, QC, Canada
| | - GA Rouleau
- Department of Medicine, Centre of Excellence in Neuromics, CHUM Research Centre, University of Montreal, Montreal, QC, Canada
- CHU Sainte-Justine Research Center, Montreal, QC, Canada
| |
Collapse
|
48
|
Zanni G, Bertini ES. X-linked disorders with cerebellar dysgenesis. Orphanet J Rare Dis 2011; 6:24. [PMID: 21569638 PMCID: PMC3115841 DOI: 10.1186/1750-1172-6-24] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Accepted: 05/15/2011] [Indexed: 12/15/2022] Open
Abstract
X-linked disorders with cerebellar dysgenesis (XLCD) are a genetically heterogeneous and clinically variable group of disorders in which the hallmark is a cerebellar defect (hypoplasia, atrophy or dysplasia) visible on brain imaging, caused by gene mutations or genomic imbalances on the X-chromosome. The neurological features of XLCD include hypotonia, developmental delay, intellectual disability, ataxia and/or other cerebellar signs. Normal cognitive development has also been reported. Cerebellar dysgenesis may be isolated or associated with other brain malformations or multiorgan involvement. There are at least 15 genes on the X-chromosome that have been constantly or occasionally associated with a pathological cerebellar phenotype. 8 XLCD loci have been mapped and several families with X-linked inheritance have been reported. Recently, two recurrent duplication syndromes in Xq28 have been associated with cerebellar hypoplasia. Given the report of several forms of XLCD and the excess of males with ataxia, this group of conditions is probably underestimated and families of patients with neuroradiological and clinical evidence of a cerebellar disorder should be counseled for high risk of X-linked inheritance.
Collapse
Affiliation(s)
- Ginevra Zanni
- Unit of Molecular Medicine, Departement of Neurosciences, Bambino Gesù ediatric Research Hospital, 4 Piazza S. Onofrio, 00165 Rome, Italy.
| | | |
Collapse
|
49
|
Anderson C, Davies JH, Lamont L, Foulds N. Early pontocerebellar hypoplasia with vanishing testes: A new syndrome? Am J Med Genet A 2011; 155A:667-72. [PMID: 21594990 DOI: 10.1002/ajmg.a.33897] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2010] [Accepted: 12/10/2010] [Indexed: 11/11/2022]
Abstract
We report on a full-term male infant with hypoplastic male genitalia and bilateral impalpable testes noted at birth, who over the following months developed increasing hypotonia, apneic episodes, and seizures resulting in his death at age 24 weeks. During this period regression of penile corporeal tissue was observed. An endocrinological diagnosis of primary hypogonadism was made and cerebral imaging at 19 weeks showed reduced periventricular white matter with marked pontocerebellar hypoplasia (PCH)/atrophy, but a well-developed posterior fossa. We propose that this condition constitutes a new form of severe PCH/atrophy with testicular regression that has onset in the fetal period.
Collapse
|
50
|
Al-Owain M, Kaya N, Al-Zaidan H, Al-Hashmi N, Al-Bakheet A, Al-Muhaizea M, Chedrawi A, Basran RK, Milunsky A. Novel intragenic deletion in OPHN1 in a family causing XLMR with cerebellar hypoplasia and distinctive facial appearance. Clin Genet 2011; 79:363-70. [DOI: 10.1111/j.1399-0004.2010.01462.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|