1
|
Jung H, Kim S, Ko J, Um JW. Intracellular signaling mechanisms that shape postsynaptic GABAergic synapses. Curr Opin Neurobiol 2023; 81:102728. [PMID: 37236068 DOI: 10.1016/j.conb.2023.102728] [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: 02/12/2023] [Revised: 04/21/2023] [Accepted: 04/23/2023] [Indexed: 05/28/2023]
Abstract
Postsynaptic GABAergic receptors interact with various membrane and intracellular proteins to mediate inhibitory synaptic transmission. They form structural and/or signaling synaptic protein complexes that perform a variety of postsynaptic functions. In particular, the key GABAergic synaptic scaffold, gephyrin, and its interacting partners govern downstream signaling pathways that are essential for GABAergic synapse development, transmission, and plasticity. In this review, we discuss recent researches on GABAergic synaptic signaling pathways. We also outline the main outstanding issues that need to be addressed in this field and highlight the association of dysregulated GABAergic synaptic signaling with the onset of various brain disorders.
Collapse
Affiliation(s)
- Hyeji Jung
- Department of Brain Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), 333 Techno Jungangdae-Ro, Hyeonpoong-Eup, Dalseong-Gun, Daegu 42988, South Korea
| | - Seungjoon Kim
- Department of Brain Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), 333 Techno Jungangdae-Ro, Hyeonpoong-Eup, Dalseong-Gun, Daegu 42988, South Korea; Center for Synapse Diversity and Specificity, DGIST, 333 Techno Jungangdae-Ro, Hyeonpoong-Eup, Dalseong-Gun, Daegu 42988, South Korea
| | - Jaewon Ko
- Department of Brain Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), 333 Techno Jungangdae-Ro, Hyeonpoong-Eup, Dalseong-Gun, Daegu 42988, South Korea; Center for Synapse Diversity and Specificity, DGIST, 333 Techno Jungangdae-Ro, Hyeonpoong-Eup, Dalseong-Gun, Daegu 42988, South Korea
| | - Ji Won Um
- Department of Brain Sciences, Daegu Gyeongbuk Institute of Science and Technology (DGIST), 333 Techno Jungangdae-Ro, Hyeonpoong-Eup, Dalseong-Gun, Daegu 42988, South Korea; Center for Synapse Diversity and Specificity, DGIST, 333 Techno Jungangdae-Ro, Hyeonpoong-Eup, Dalseong-Gun, Daegu 42988, South Korea.
| |
Collapse
|
2
|
Mao R, Xu S, Sun G, Yu Y, Zuo Z, Wang Y, Yang K, Zhang Z, Yang W. Triptolide injection reduces Alzheimer's disease-like pathology in mice. Synapse 2023; 77:e22261. [PMID: 36633502 DOI: 10.1002/syn.22261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 12/21/2022] [Accepted: 01/08/2023] [Indexed: 01/13/2023]
Abstract
Triptolide is an epoxidized diterpene lactone isolated from Tripterygium wilfordii. Studies have shown that triptolide exerts organ-protective effects. However, it remains unknown whether triptolide improves Alzheimer's disease (AD)-like presentations. Thirty healthy 8-week-old male C57BL/6J mice were randomly divided into control (n = 10), model (n = 10), and triptolide (n = 10) groups. Amyloid-β (Aβ)42 was injected bilaterally into the ventricles of mice in the model group. Triptolide was injected intraperitoneally daily after injecting Aβ42 (a total of 30 days) in the triptolide group. Learning and memory were tested using the Morris water maze test. The deposition of Aβ42 in the hippocampus was detected using immunohistochemical staining. In the hippocampus, three synaptic-associated proteins-gephyrin, collybistin, and GABRA1 -were detected by western blotting. Furthermore, we used ELISA to detect proinflammatory cytokines, including TNF-α and IL-1β, in the blood and hippocampus. Moreover, superoxide dismutase (SOD), malondialdehyde (MDA), and GSH levels were measured using the corresponding kits. We found that triptolide improved spatial learning and memory in AD-like mice. Additionally, triptolide maintained the expression of gephyrin, collybistin, and GABRA1 and reduced Aβ in these mice. Additionally, triptolide reduced the expression of inflammatory cytokines and decreased oxidative damage in AD-like mice. Our study suggests that triptolide attenuates AD-like changes in the mouse brain.
Collapse
Affiliation(s)
- Rui Mao
- Department of Neurology, Sinopharm Dongfeng General Hospital, Hubei University of Medicine, Shiyan, Hubei, China
| | - Shihao Xu
- Department of Neurology, Sinopharm Dongfeng General Hospital, Hubei University of Medicine, Shiyan, Hubei, China
| | - Guangwen Sun
- Department of Neurology, Sinopharm Dongfeng General Hospital, Hubei University of Medicine, Shiyan, Hubei, China
- Department of Neurology, Sinopharm Dongfeng General Hospital, Jinzhou Medical University Union Training Base, Jinzhou, China
| | - Yingying Yu
- Department of Neurology, Sinopharm Dongfeng General Hospital, Hubei University of Medicine, Shiyan, Hubei, China
- Department of Neurology, Sinopharm Dongfeng General Hospital, Jinzhou Medical University Union Training Base, Jinzhou, China
| | - Zhiyi Zuo
- Department of Anesthesiology, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Yuanyuan Wang
- Department of Neurology, Sinopharm Dongfeng General Hospital, Hubei University of Medicine, Shiyan, Hubei, China
| | - Kun Yang
- Department of Anesthesiology, Sinopharm Dongfeng General Hospital, Jinzhou Medical University Union Training Base, Jinzhou, China
| | - Zhen Zhang
- Department of Orthopedics, Sinopharm Dongfeng General Hospital, Hubei University of Medicine, Shiyan, Hubei, China
| | - Wenqiong Yang
- Department of Neurology, Sinopharm Dongfeng General Hospital, Hubei University of Medicine, Shiyan, Hubei, China
| |
Collapse
|
3
|
Melillo R, Leisman G, Machado C, Machado-Ferrer Y, Chinchilla-Acosta M, Kamgang S, Melillo T, Carmeli E. Retained Primitive Reflexes and Potential for Intervention in Autistic Spectrum Disorders. Front Neurol 2022; 13:922322. [PMID: 35873782 PMCID: PMC9301367 DOI: 10.3389/fneur.2022.922322] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Accepted: 06/06/2022] [Indexed: 11/13/2022] Open
Abstract
We provide evidence to support the contention that many aspects of Autistic Spectrum Disorder (ASD) are related to interregional brain functional disconnectivity associated with maturational delays in the development of brain networks. We think a delay in brain maturation in some networks may result in an increase in cortical maturation and development in other networks, leading to a developmental asynchrony and an unevenness of functional skills and symptoms. The paper supports the close relationship between retained primitive reflexes and cognitive and motor function in general and in ASD in particular provided to indicate that the inhibition of RPRs can effect positive change in ASD.
Collapse
Affiliation(s)
- Robert Melillo
- Movement and Cognition Laboratory, Department of Physical Therapy, University of Haifa, Haifa, Israel
| | - Gerry Leisman
- Movement and Cognition Laboratory, Department of Physical Therapy, University of Haifa, Haifa, Israel
- Department of Neurology, University of the Medical Sciences of Havana, Havana, Cuba
| | - Calixto Machado
- Department of Clinical Neurophysiology, Institute for Neurology and Neurosurgery, Havana, Cuba
| | - Yanin Machado-Ferrer
- Department of Clinical Neurophysiology, Institute for Neurology and Neurosurgery, Havana, Cuba
| | | | - Shanine Kamgang
- Department of Neuroscience, Carleton University, Ottawa, ON, Canada
| | - Ty Melillo
- Northeast College of the Health Sciences, Seneca Falls, New York, NY, United States
| | - Eli Carmeli
- Movement and Cognition Laboratory, Department of Physical Therapy, University of Haifa, Haifa, Israel
| |
Collapse
|
4
|
Hines DJ, Contreras A, Garcia B, Barker JS, Boren AJ, Moufawad El Achkar C, Moss SJ, Hines RM. Human ARHGEF9 intellectual disability syndrome is phenocopied by a mutation that disrupts collybistin binding to the GABA A receptor α2 subunit. Mol Psychiatry 2022; 27:1729-1741. [PMID: 35169261 PMCID: PMC9095487 DOI: 10.1038/s41380-022-01468-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 01/12/2022] [Accepted: 01/26/2022] [Indexed: 11/20/2022]
Abstract
Intellectual disability (ID) is a common neurodevelopmental disorder that can arise from genetic mutations ranging from trisomy to single nucleotide polymorphism. Mutations in a growing number of single genes have been identified as causative in ID, including ARHGEF9. Evaluation of 41 ARHGEF9 patient reports shows ubiquitous inclusion of ID, along with other frequently reported symptoms of epilepsy, abnormal baseline EEG activity, behavioral symptoms, and sleep disturbances. ARHGEF9 codes for the Cdc42 Guanine Nucleotide Exchange Factor 9 collybistin (Cb), a known regulator of inhibitory synapse function via direct interaction with the adhesion molecule neuroligin-2 and the α2 subunit of GABAA receptors. We mutate the Cb binding motif within the large intracellular loop of α2 replacing it with the binding motif for gephyrin from the α1 subunit (Gabra2-1). The Gabra2-1 mutation causes a strong downregulation of Cb expression, particularly at cholecystokinin basket cell inhibitory synapses. Gabra2-1 mice have deficits in working and recognition memory, as well as hyperactivity, anxiety, and reduced social preference, recapitulating the frequently reported features of ARHGEF9 patients. Gabra2-1 mice also have spontaneous seizures during postnatal development which can lead to mortality, and baseline abnormalities in low-frequency wavelengths of the EEG. EEG abnormalities are vigilance state-specific and manifest as sleep disturbance including increased time in wake and a loss of free-running rhythmicity in the absence of light as zeitgeber. Gabra2-1 mice phenocopy multiple features of human ARHGEF9 mutation, and reveal α2 subunit-containing GABAA receptors as a druggable target for treatment of this complex ID syndrome.
Collapse
Affiliation(s)
- Dustin J Hines
- Department of Psychology, University of Nevada Las Vegas, Las Vegas, NV, USA
| | - April Contreras
- Department of Psychology, University of Nevada Las Vegas, Las Vegas, NV, USA
| | - Betsua Garcia
- Department of Psychology, University of Nevada Las Vegas, Las Vegas, NV, USA
| | - Jeffrey S Barker
- Department of Psychology, University of Nevada Las Vegas, Las Vegas, NV, USA
| | - Austin J Boren
- Department of Psychology, University of Nevada Las Vegas, Las Vegas, NV, USA
| | | | - Stephen J Moss
- Department of Neuroscience, Tufts University School of Medicine, Boston, MA, USA
| | - Rochelle M Hines
- Department of Psychology, University of Nevada Las Vegas, Las Vegas, NV, USA.
| |
Collapse
|
5
|
Blaise AM, Corcoran EE, Wattenberg ES, Zhang YL, Cottrell JR, Koleske AJ. In vitro fluorescence assay to measure GDP/GTP exchange of guanine nucleotide exchange factors of Rho family GTPases. Biol Methods Protoc 2021; 7:bpab024. [PMID: 35087952 PMCID: PMC8789339 DOI: 10.1093/biomethods/bpab024] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 12/14/2021] [Indexed: 11/14/2022] Open
Abstract
Guanine nucleotide exchange factors (GEFs) are enzymes that promote the activation of GTPases through GTP loading. Whole exome sequencing has identified rare variants in GEFs that are associated with disease, demonstrating that GEFs play critical roles in human development. However, the consequences of these rare variants can only be understood through measuring their effects on cellular activity. Here, we provide a detailed, user-friendly protocol for purification and fluorescence-based analysis of the two GEF domains within the protein, Trio. This analysis offers a straight-forward, quantitative tool to test the activity of GEF domains on their respective GTPases, as well as utilize high-throughput screening to identify regulators and inhibitors. This protocol can be adapted for characterization of other Rho family GEFs. Such analyses are crucial for the complete understanding of the roles of GEF genetic variants in human development and disease.
Collapse
Affiliation(s)
- Alyssa M Blaise
- Departments of Molecular Biophysics and Biochemistry, Yale School of Medicine, Yale University, New Haven, CT 06520-8024, USA
- Neuroscience, Yale School of Medicine, Yale University, New Haven, CT 06520-8024, USA
| | - Ellen E Corcoran
- Departments of Molecular Biophysics and Biochemistry, Yale School of Medicine, Yale University, New Haven, CT 06520-8024, USA
- Neuroscience, Yale School of Medicine, Yale University, New Haven, CT 06520-8024, USA
| | - Eve S Wattenberg
- Departments of Molecular Biophysics and Biochemistry, Yale School of Medicine, Yale University, New Haven, CT 06520-8024, USA
- Neuroscience, Yale School of Medicine, Yale University, New Haven, CT 06520-8024, USA
| | - Yan-Ling Zhang
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Jeffrey R Cottrell
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Anthony J Koleske
- Departments of Molecular Biophysics and Biochemistry, Yale School of Medicine, Yale University, New Haven, CT 06520-8024, USA
- Neuroscience, Yale School of Medicine, Yale University, New Haven, CT 06520-8024, USA
| |
Collapse
|
6
|
Qiu T, Dai Q, Wang Q. A novel de novo hemizygous ARHGEF9 mutation associated with severe intellectual disability and epilepsy: a case report. J Int Med Res 2021; 49:3000605211058372. [PMID: 34851771 PMCID: PMC8647271 DOI: 10.1177/03000605211058372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
Abstract
ARHGEF9 encodes collybistin, a brain-specific guanosine diphosphate-guanosine-5′-triphosphate exchange factor that plays an important role in clustering of gephyrin and γ-aminobutyric acid type A receptors in the postsynaptic membrane. Overwhelming evidence suggests that defects in this protein can cause X-linked intellectual disability, which comprises a series of clinical phenotypes, including autism spectrum disorder, behavior disorder, intellectual disability, and febrile seizures. Here, we report a boy with clinical symptoms of severe intellectual disability, epilepsy, and developmental delay and regression. Trio exome sequencing (trio-clinical exome sequencing) identified a novel hemizygous deletion, c.656_c.669delACTTCTTTGAGGCC (p. His219Leu fs*9), in exon 5 of ARHGEF9. This variant was not reported in either the Genome Aggregation Database or our database of 309 patients with neurodevelopmental disorders. Oxcarbazepine and levetiracetam reduced the frequency of the patient’s epileptic seizures to a certain extent, but psychomotor developmental delay and developmental regression became more obvious with age. This case study seeks to report a de novo loss-of-function mutation of ARHGEF9, aiming to emphasize the genetic diagnosis of X-linked intellectual disability and further improve knowledge of the ethnic distribution of ARHGEF9 mutations.
Collapse
Affiliation(s)
- Tong Qiu
- Division of Pediatrics, West China Second University Hospital, Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, State Key Laboratory of Biotherapy and Collaborative Innovation Center of Biotherapy, Sichuan University, Chengdu, China
| | - Qian Dai
- Division of Pediatrics, West China Second University Hospital, Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, State Key Laboratory of Biotherapy and Collaborative Innovation Center of Biotherapy, Sichuan University, Chengdu, China
| | - Qiu Wang
- Division of Rehabilitation Medicine, West China Second University Hospital, Sichuan University, Chengdu, China
| |
Collapse
|
7
|
Blazie SM, Takayanagi-Kiya S, McCulloch KA, Jin Y. Eukaryotic initiation factor EIF-3.G augments mRNA translation efficiency to regulate neuronal activity. eLife 2021; 10:68336. [PMID: 34323215 PMCID: PMC8354637 DOI: 10.7554/elife.68336] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 07/28/2021] [Indexed: 11/18/2022] Open
Abstract
The translation initiation complex eIF3 imparts specialized functions to regulate protein expression. However, understanding of eIF3 activities in neurons remains limited despite widespread dysregulation of eIF3 subunits in neurological disorders. Here, we report a selective role of the C. elegans RNA-binding subunit EIF-3.G in shaping the neuronal protein landscape. We identify a missense mutation in the conserved Zinc-Finger (ZF) of EIF-3.G that acts in a gain-of-function manner to dampen neuronal hyperexcitation. Using neuron-type-specific seCLIP, we systematically mapped EIF-3.G-mRNA interactions and identified EIF-3.G occupancy on GC-rich 5′UTRs of a select set of mRNAs enriched in activity-dependent functions. We demonstrate that the ZF mutation in EIF-3.G alters translation in a 5′UTR-dependent manner. Our study reveals an in vivo mechanism for eIF3 in governing neuronal protein levels to control neuronal activity states and offers insights into how eIF3 dysregulation contributes to neurological disorders.
Collapse
Affiliation(s)
- Stephen M Blazie
- Section of Neurobiology, Division of Biological Sciences, University of California San Diego, La Jolla, United States
| | - Seika Takayanagi-Kiya
- Section of Neurobiology, Division of Biological Sciences, University of California San Diego, La Jolla, United States
| | - Katherine A McCulloch
- Section of Neurobiology, Division of Biological Sciences, University of California San Diego, La Jolla, United States
| | - Yishi Jin
- Section of Neurobiology, Division of Biological Sciences, University of California San Diego, La Jolla, United States
| |
Collapse
|
8
|
The role of GABAergic signalling in neurodevelopmental disorders. Nat Rev Neurosci 2021; 22:290-307. [PMID: 33772226 PMCID: PMC9001156 DOI: 10.1038/s41583-021-00443-x] [Citation(s) in RCA: 66] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/12/2021] [Indexed: 02/08/2023]
Abstract
GABAergic inhibition shapes the connectivity, activity and plasticity of the brain. A series of exciting new discoveries provides compelling evidence that disruptions in a number of key facets of GABAergic inhibition have critical roles in the aetiology of neurodevelopmental disorders (NDDs). These facets include the generation, migration and survival of GABAergic neurons, the formation of GABAergic synapses and circuit connectivity, and the dynamic regulation of the efficacy of GABAergic signalling through neuronal chloride transporters. In this Review, we discuss recent work that elucidates the functions and dysfunctions of GABAergic signalling in health and disease, that uncovers the contribution of GABAergic neural circuit dysfunction to NDD aetiology and that leverages such mechanistic insights to advance precision medicine for the treatment of NDDs.
Collapse
|
9
|
Wagner S, Lee C, Rojas L, Specht CG, Rhee J, Brose N, Papadopoulos T. The α3 subunit of GABA A receptors promotes formation of inhibitory synapses in the absence of collybistin. J Biol Chem 2021; 296:100709. [PMID: 33901490 PMCID: PMC8141935 DOI: 10.1016/j.jbc.2021.100709] [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: 10/20/2020] [Revised: 04/14/2021] [Accepted: 04/22/2021] [Indexed: 01/03/2023] Open
Abstract
Signaling at nerve cell synapses is a key determinant of proper brain function, and synaptic defects—or synaptopathies—are at the basis of many neurological and psychiatric disorders. Collybistin (CB), a brain-specific guanine nucleotide exchange factor, is essential for the formation of γ-aminobutyric acidergic (GABAergic) postsynapses in defined regions of the mammalian forebrain, including the hippocampus and basolateral amygdala. This process depends on a direct interaction of CB with the scaffolding protein gephyrin, which leads to the redistribution of gephyrin into submembranous clusters at nascent inhibitory synapses. Strikingly, synaptic clustering of gephyrin and GABAA type A receptors (GABAARs) in several brain regions, including the cerebral cortex and certain thalamic areas, is unperturbed in CB-deficient mice, indicating that the formation of a substantial subset of inhibitory postsynapses must be controlled by gephyrin-interacting proteins other than CB. Previous studies indicated that the α3 subunit of GABAARs (GABAAR-α3) binds directly and with high affinity to gephyrin. Here, we provide evidence (i) that a homooligomeric GABAAR-α3A343W mutant induces the formation of submembranous gephyrin clusters independently of CB in COS-7 cells, (ii) that gephyrin clustering is unaltered in the neuronal subpopulations endogenously expressing the GABAAR-α3 in CB-deficient brains, and (iii) that exogenous expression of GABAAR-α3 partially rescues impaired gephyrin clustering in CB-deficient hippocampal neurons. Our results identify an important role of GABAAR-α3 in promoting gephyrin-mediated and CB-independent formation of inhibitory postsynapses.
Collapse
Affiliation(s)
- Sven Wagner
- Department of Molecular Neurobiology, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - ChoongKu Lee
- Department of Molecular Neurobiology, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Lucia Rojas
- Department of Molecular Neurobiology, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Christian G Specht
- Diseases and Hormones of the Nervous System (DHNS), Inserm U1195, Université Paris-Saclay, Le Kremlin-Bicêtre, France
| | - JeongSeop Rhee
- Department of Molecular Neurobiology, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | - Nils Brose
- Department of Molecular Neurobiology, Max Planck Institute of Experimental Medicine, Göttingen, Germany
| | | |
Collapse
|
10
|
Ghesh L, Besnard T, Nizon M, Trochu E, Landeau-Trottier G, Breheret F, Thauvin-Robinet C, Bruel AL, Kuentz P, Coubes C, Cuisset L, Mignot C, Keren B, Bézieau S, Cogné B. Loss-of-function variants in ARHGEF9 are associated with an X-linked intellectual disability dominant disorder. Hum Mutat 2021; 42:498-505. [PMID: 33600053 DOI: 10.1002/humu.24188] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 01/28/2021] [Accepted: 02/14/2021] [Indexed: 01/12/2023]
Abstract
ARHGEF9 defects lead to an X-linked intellectual disability disorder related to inhibitory synaptic dysfunction. This condition is more frequent in males, with a few affected females reported. Up to now, sequence variants and gross deletions have been identified in males, while only chromosomal aberrations have been reported in affected females who showed a skewed pattern of X-chromosome inactivation (XCI), suggesting an X-linked recessive (XLR) disorder. We report three novel loss-of-function (LoF) variants in ARHGEF9: A de novo synonymous variant affecting splicing (NM_015185.2: c.1056G>A, p.(Lys352=)) in one female; a nonsense variant in another female (c.865C>T, p.(Arg289*)), that is, also present as a somatically mosaic variant in her father, and a de novo nonsense variant in a boy (c.899G>A; p.(Trp300*)). Both females showed a random XCI. Thus, we suggest that missense variants are responsible for an XLR disorder affecting males and that LoF variants, mainly occurring de novo, may be responsible for an X-linked dominant disorder affecting males and females.
Collapse
Affiliation(s)
- Leïla Ghesh
- Service de Génétique Médicale, Centre Hospitalier Universitaire de Nantes, Nantes, France
| | - Thomas Besnard
- Service de Génétique Médicale, Centre Hospitalier Universitaire de Nantes, Nantes, France
- l'institut du thorax, Université de Nantes, CNRS, INSERM, Nantes, France
| | - Mathilde Nizon
- Service de Génétique Médicale, Centre Hospitalier Universitaire de Nantes, Nantes, France
- l'institut du thorax, Université de Nantes, CNRS, INSERM, Nantes, France
| | - Eva Trochu
- Service de Génétique Médicale, Centre Hospitalier Universitaire de Nantes, Nantes, France
| | | | - Flora Breheret
- Service de Génétique Médicale, Centre Hospitalier Universitaire de Nantes, Nantes, France
| | - Christel Thauvin-Robinet
- FHU TRANSLAD, Centre Hospitalier Universitaire Dijon-Bourgogne et Université de Bourgogne-Franche Comté, Dijon, France
- Génétique des Anomalies du Développement, Inserm UMR 1231, Université de Bourgogne, Dijon, France
- Centre de Génétique et Centre de Référence Déficience Intellectuelle de causes rares, Hôpital d'Enfants, Centre Hospitalier Universitaire Dijon-Bourgogne, Dijon, France
- UF Innovation en diagnostic génomique des maladies rares, CHU Dijon, Dijon, France
| | - Ange-Line Bruel
- FHU TRANSLAD, Centre Hospitalier Universitaire Dijon-Bourgogne et Université de Bourgogne-Franche Comté, Dijon, France
- Génétique des Anomalies du Développement, Inserm UMR 1231, Université de Bourgogne, Dijon, France
- UF Innovation en diagnostic génomique des maladies rares, CHU Dijon, Dijon, France
| | - Paul Kuentz
- FHU TRANSLAD, Centre Hospitalier Universitaire Dijon-Bourgogne et Université de Bourgogne-Franche Comté, Dijon, France
- Génétique des Anomalies du Développement, Inserm UMR 1231, Université de Bourgogne, Dijon, France
| | - Christine Coubes
- Département de Génétique Médicale, Maladies Rares et Médecine Personnalisée, Hôpital Arnaud de Villeneuve, CHU de Montpellier, Montpellier, France
| | - Laurence Cuisset
- Laboratoire de Génétique et Biologie Moléculaires, Département Médico-Universitaire BioPhyGen, Hôpital Cochin, APHP, Université de Paris, Paris, France
| | - Cyril Mignot
- Institut du Cerveau et de la Moelle épinière, ICM, INSERM, U 1127, CNRS UMR 7225, Sorbonne Universités, UPMC Univ Paris 06 UMR S 1127, Paris, France
- Service de Génétique clinique et Médicale, CHU Paris, Hôpital Pitié-Salpêtrière, Paris, France
| | - Boris Keren
- Service de Génétique clinique et Médicale, CHU Paris, Hôpital Pitié-Salpêtrière, Paris, France
| | - Stéphane Bézieau
- Service de Génétique Médicale, Centre Hospitalier Universitaire de Nantes, Nantes, France
- l'institut du thorax, Université de Nantes, CNRS, INSERM, Nantes, France
| | - Benjamin Cogné
- Service de Génétique Médicale, Centre Hospitalier Universitaire de Nantes, Nantes, France
- l'institut du thorax, Université de Nantes, CNRS, INSERM, Nantes, France
| |
Collapse
|
11
|
Thongkorn S, Kanlayaprasit S, Panjabud P, Saeliw T, Jantheang T, Kasitipradit K, Sarobol S, Jindatip D, Hu VW, Tencomnao T, Kikkawa T, Sato T, Osumi N, Sarachana T. Sex differences in the effects of prenatal bisphenol A exposure on autism-related genes and their relationships with the hippocampus functions. Sci Rep 2021; 11:1241. [PMID: 33441873 PMCID: PMC7806752 DOI: 10.1038/s41598-020-80390-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 12/21/2020] [Indexed: 01/29/2023] Open
Abstract
Our recent study has shown that prenatal exposure to bisphenol A (BPA) altered the expression of genes associated with autism spectrum disorder (ASD). In this study, we further investigated the effects of prenatal BPA exposure on ASD-related genes known to regulate neuronal viability, neuritogenesis, and learning/memory, and assessed these functions in the offspring of exposed pregnant rats. We found that prenatal BPA exposure increased neurite length, the number of primary neurites, and the number of neurite branches, but reduced the size of the hippocampal cell body in both sexes of the offspring. However, in utero exposure to BPA decreased the neuronal viability and the neuronal density in the hippocampus and impaired learning/memory only in the male offspring while the females were not affected. Interestingly, the expression of several ASD-related genes (e.g. Mief2, Eif3h, Cux1, and Atp8a1) in the hippocampus were dysregulated and showed a sex-specific correlation with neuronal viability, neuritogenesis, and/or learning/memory. The findings from this study suggest that prenatal BPA exposure disrupts ASD-related genes involved in neuronal viability, neuritogenesis, and learning/memory in a sex-dependent manner, and these genes may play an important role in the risk and the higher prevalence of ASD in males subjected to prenatal BPA exposure.
Collapse
Affiliation(s)
- Surangrat Thongkorn
- grid.7922.e0000 0001 0244 7875The Ph.D. Program in Clinical Biochemistry and Molecular Medicine, Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Songphon Kanlayaprasit
- grid.7922.e0000 0001 0244 7875The Ph.D. Program in Clinical Biochemistry and Molecular Medicine, Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Pawinee Panjabud
- grid.7922.e0000 0001 0244 7875The Ph.D. Program in Clinical Biochemistry and Molecular Medicine, Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Thanit Saeliw
- grid.7922.e0000 0001 0244 7875The Ph.D. Program in Clinical Biochemistry and Molecular Medicine, Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Thanawin Jantheang
- grid.7922.e0000 0001 0244 7875The Ph.D. Program in Clinical Biochemistry and Molecular Medicine, Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Kasidit Kasitipradit
- grid.7922.e0000 0001 0244 7875The Ph.D. Program in Clinical Biochemistry and Molecular Medicine, Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Suthathip Sarobol
- grid.411628.80000 0000 9758 8584Specimen Center, Department of Laboratory Medicine, King Chulalongkorn Memorial Hospital, Bangkok, Thailand
| | - Depicha Jindatip
- grid.7922.e0000 0001 0244 7875Department of Anatomy, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand ,grid.7922.e0000 0001 0244 7875SYstems Neuroscience of Autism and PSychiatric Disorders (SYNAPS) Research Unit, Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Valerie W. Hu
- grid.253615.60000 0004 1936 9510Department of Biochemistry and Molecular Medicine, The George Washington University School of Medicine and Health Sciences, The George Washington University, Washington, DC USA
| | - Tewin Tencomnao
- grid.7922.e0000 0001 0244 7875Age-Related Inflammation and Degeneration Research Unit, Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Takako Kikkawa
- grid.69566.3a0000 0001 2248 6943Department of Developmental Neuroscience, United Centers for Advanced Research and Translational Medicine (ART), Tohoku University Graduate School of Medicine, Sendai, Miyagi Japan
| | - Tatsuya Sato
- grid.412754.10000 0000 9956 3487Department of Healthcare Management, Faculty of Health Sciences, Tohoku Fukushi University, Sendai, Miyagi Japan
| | - Noriko Osumi
- grid.69566.3a0000 0001 2248 6943Department of Developmental Neuroscience, United Centers for Advanced Research and Translational Medicine (ART), Tohoku University Graduate School of Medicine, Sendai, Miyagi Japan
| | - Tewarit Sarachana
- grid.7922.e0000 0001 0244 7875SYstems Neuroscience of Autism and PSychiatric Disorders (SYNAPS) Research Unit, Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand ,grid.7922.e0000 0001 0244 7875Age-Related Inflammation and Degeneration Research Unit, Department of Clinical Chemistry, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
| |
Collapse
|
12
|
Experimental Models to Study Autism Spectrum Disorders: hiPSCs, Rodents and Zebrafish. Genes (Basel) 2020; 11:genes11111376. [PMID: 33233737 PMCID: PMC7699923 DOI: 10.3390/genes11111376] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 10/26/2020] [Accepted: 11/18/2020] [Indexed: 02/07/2023] Open
Abstract
Autism Spectrum Disorders (ASD) affect around 1.5% of the global population, which manifest alterations in communication and socialization, as well as repetitive behaviors or restricted interests. ASD is a complex disorder with known environmental and genetic contributors; however, ASD etiology is far from being clear. In the past decades, many efforts have been put into developing new models to study ASD, both in vitro and in vivo. These models have a lot of potential to help to validate some of the previously associated risk factors to the development of the disorder, and to test new potential therapies that help to alleviate ASD symptoms. The present review is focused on the recent advances towards the generation of models for the study of ASD, which would be a useful tool to decipher the bases of the disorder, as well as to conduct drug screenings that hopefully lead to the identification of useful compounds to help patients deal with the symptoms of ASD.
Collapse
|
13
|
Scala M, Zonneveld-Huijssoon E, Brienza M, Mecarelli O, van der Hout AH, Zambrelli E, Turner K, Zara F, Peron A, Vignoli A, Striano P. De novo ARHGEF9 missense variants associated with neurodevelopmental disorder in females: expanding the genotypic and phenotypic spectrum of ARHGEF9 disease in females. Neurogenetics 2020; 22:87-94. [PMID: 32939676 DOI: 10.1007/s10048-020-00622-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Accepted: 07/21/2020] [Indexed: 11/24/2022]
Abstract
Individuals harboring pathogenic variants in ARHGEF9, encoding an essential submembrane protein for gamma-aminobutyric acid (GABA)-ergic synapses named collybistin, show intellectual disability (ID), facial dysmorphism, behavioral disorders, and epilepsy. Only few affected females carrying large chromosomal rearrangements involving ARHGEF9 have been reported so far. Through next-generation sequencing (NGS)-based panels, we identified two single nucleotide variants (SNVs) in ARHGEF9 in two females with neurodevelopmental features. Sanger sequencing revealed that these variants were de novo. The X-inactivation pattern in peripheral blood cells was random. We report the first affected females harboring de novo SNVs in ARHGEF9, expanding the genotypic and phenotypic spectrum of ARHGEF9-related neurodevelopmental disorder in females.
Collapse
Affiliation(s)
- Marcello Scala
- Pediatric Neurology and Muscular Diseases Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy. .,Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy.
| | - Evelien Zonneveld-Huijssoon
- Department of Genetics, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Marianna Brienza
- Department of Human Neurosciences, Policlinico Umberto I Hospital, Sapienza University, Rome, Italy
| | - Oriano Mecarelli
- Department of Human Neurosciences, Policlinico Umberto I Hospital, Sapienza University, Rome, Italy
| | - Annemarie H van der Hout
- Department of Genetics, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Elena Zambrelli
- Epilepsy Center - Sleep Medicine Center, San Paolo Hospital, Milan, Italy
| | - Katherine Turner
- Epilepsy Center - Sleep Medicine Center, San Paolo Hospital, Milan, Italy
| | - Federico Zara
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy.,Unit of Medical Genetics, IRCCS Istituto Giannina Gaslini, Genoa, Italy
| | - Angela Peron
- Child Neuropsychiatry Unit - Epilepsy Center, San Paolo Hospital, Milan, Italy.,Department of Health Sciences, Università degli Studi di Milano, Milan, Italy.,Department of Pediatrics, Division of Medical Genetics, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Aglaia Vignoli
- Child Neuropsychiatry Unit - Epilepsy Center, San Paolo Hospital, Milan, Italy.,Department of Health Sciences, Università degli Studi di Milano, Milan, Italy
| | - Pasquale Striano
- Pediatric Neurology and Muscular Diseases Unit, IRCCS Istituto Giannina Gaslini, Genoa, Italy.,Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy
| |
Collapse
|
14
|
Drakulic D, Djurovic S, Syed YA, Trattaro S, Caporale N, Falk A, Ofir R, Heine VM, Chawner SJRA, Rodriguez-Moreno A, van den Bree MBM, Testa G, Petrakis S, Harwood AJ. Copy number variants (CNVs): a powerful tool for iPSC-based modelling of ASD. Mol Autism 2020; 11:42. [PMID: 32487215 PMCID: PMC7268297 DOI: 10.1186/s13229-020-00343-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 05/04/2020] [Indexed: 02/06/2023] Open
Abstract
Patients diagnosed with chromosome microdeletions or duplications, known as copy number variants (CNVs), present a unique opportunity to investigate the relationship between patient genotype and cell phenotype. CNVs have high genetic penetrance and give a good correlation between gene locus and patient clinical phenotype. This is especially effective for the study of patients with neurodevelopmental disorders (NDD), including those falling within the autism spectrum disorders (ASD). A key question is whether this correlation between genetics and clinical presentation at the level of the patient can be translated to the cell phenotypes arising from the neurodevelopment of patient induced pluripotent stem cells (iPSCs).Here, we examine how iPSCs derived from ASD patients with an associated CNV inform our understanding of the genetic and biological mechanisms underlying the aetiology of ASD. We consider selection of genetically characterised patient iPSCs; use of appropriate control lines; aspects of human neurocellular biology that can capture in vitro the patient clinical phenotype; and current limitations of patient iPSC-based studies. Finally, we consider how future research may be enhanced to maximise the utility of CNV patients for research of pathological mechanisms or therapeutic targets.
Collapse
Affiliation(s)
- Danijela Drakulic
- Institute of Molecular Genetics and Genetic Engineering, University of Belgrade, 11042 Belgrade, 152, Serbia
| | - Srdjan Djurovic
- Department of Medical Genetics, Oslo University Hospital, 0424, Oslo, Norway
- NORMENT, Department of Clinical Science, University of Bergen, 5007, Bergen, Norway
| | - Yasir Ahmed Syed
- Neuroscience & Mental Health Research Institute, Cardiff University, Cardiff, CF24 4HQ, UK
| | - Sebastiano Trattaro
- Laboratory of Stem Cell Epigenetics, IEO, European Institute of Oncology, IRCCS, 20146, Milan, Italy
- Department of Oncology and Hemato-oncology, University of Milan, 20122, Milan, Italy
| | - Nicolò Caporale
- Laboratory of Stem Cell Epigenetics, IEO, European Institute of Oncology, IRCCS, 20146, Milan, Italy
- Department of Oncology and Hemato-oncology, University of Milan, 20122, Milan, Italy
| | - Anna Falk
- Department of Neuroscience, Karolinska Institutet, 17177, Stockholm, Sweden
| | - Rivka Ofir
- BGU-iPSC Core Facility, The Regenerative Medicine & Stem Cell (RMSC) Research Center, Ben Gurion University of the Negev, 84105, Beer-Sheva, Israel
| | - Vivi M Heine
- Complex Trait Genetics, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
- Child and Youth Psychiatry, Emma Children's Hospital, Amsterdam UMC, Amsterdam Neuroscience, Vrije Universiteit Amsterdam, 1081, Amsterdam, The Netherlands
| | - Samuel J R A Chawner
- Neuroscience & Mental Health Research Institute, Cardiff University, Cardiff, CF24 4HQ, UK
- MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Cardiff, CF24 4HQ, UK
| | - Antonio Rodriguez-Moreno
- Department of Physiology, Anatomy and Cell Biology, University Pablo de Olavide, Ctra. de Utrera, Km 1, 41013, Seville, Spain
| | - Marianne B M van den Bree
- Neuroscience & Mental Health Research Institute, Cardiff University, Cardiff, CF24 4HQ, UK
- MRC Centre for Neuropsychiatric Genetics and Genomics, Cardiff University, Cardiff, CF24 4HQ, UK
| | - Giuseppe Testa
- Laboratory of Stem Cell Epigenetics, IEO, European Institute of Oncology, IRCCS, 20146, Milan, Italy
- Department of Oncology and Hemato-oncology, University of Milan, 20122, Milan, Italy
- Human Technopole, Via Cristina Belgioioso 171, 20157, Milan, Italy
| | - Spyros Petrakis
- Institute of Applied Biosciences/Centre for Research and Technology Hellas, 57001, Thessaloniki, Greece.
| | - Adrian J Harwood
- Neuroscience & Mental Health Research Institute, Cardiff University, Cardiff, CF24 4HQ, UK.
| |
Collapse
|
15
|
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
|
16
|
Yao R, Zhang Y, Liu J, Wang J, Xu Y, Li N, Wang J, Yu T. Clinical and Molecular Characterization of Three Novel ARHGEF9 Mutations in Patients with Developmental Delay and Epilepsy. J Mol Neurosci 2020; 70:908-915. [PMID: 31942680 DOI: 10.1007/s12031-019-01465-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 12/05/2019] [Indexed: 11/30/2022]
Abstract
Mutations in the rho guanine nucleotide exchange factor 9 gene (ARHGEF9) are present in patients with heterogeneous phenotypes including psychomotor developmental delay and variable degrees of epilepsy. Malfunction of collybistin (CB) encoded by ARHGEF9 leading to impaired clustering of gephyrin-dependent glycine receptors and γ-aminobutyric acid type A (GABAα) receptors is a crucial pathogenic mechanism. Here, we report on three patients with epilepsy and mental retardation. We studied three male patients with epilepsy and mild to moderate mental retardation. We conducted targeted panel sequencing of genes known to cause inherited disorders. In vitro studies and transcriptional experiments were performed to evaluate the functional and splicing effects of these variants on CB. Two novel missense variants (p.I294T and p.R357I) and one novel splicing variant (c.381+3A>G) in ARHGEF9 were identified in the three patients, respectively. In vitro studies confirmed that the two missense variants disrupted CB-mediated accumulation of gephyrin in submembrane microclusters. Transcriptional experiments of the splicing variant revealed the presence of aberrant transcripts leading to truncated protein product. Significance: Our cases and functional studies enrich our understanding of the phenotypic and genotypic spectrum of ARHGEF9.
Collapse
Affiliation(s)
- Ruen Yao
- Department of Medical Genetics and Molecular Diagnostic Laboratory, Shanghai Children's Medical Center, Shanghai Jiaotong University School of Medicine, 1678 Dongfang Road, Shanghai, 200127, People's Republic of China
| | - Yi Zhang
- Department of Medical Genetics and Molecular Diagnostic Laboratory, Shanghai Children's Medical Center, Shanghai Jiaotong University School of Medicine, 1678 Dongfang Road, Shanghai, 200127, People's Republic of China
| | - Jie Liu
- Department of Neurology, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, People's Republic of China
| | - Jiwen Wang
- Department of Neurology, Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, People's Republic of China
| | - Yufei Xu
- Department of Medical Genetics and Molecular Diagnostic Laboratory, Shanghai Children's Medical Center, Shanghai Jiaotong University School of Medicine, 1678 Dongfang Road, Shanghai, 200127, People's Republic of China
| | - Niu Li
- Department of Medical Genetics and Molecular Diagnostic Laboratory, Shanghai Children's Medical Center, Shanghai Jiaotong University School of Medicine, 1678 Dongfang Road, Shanghai, 200127, People's Republic of China
| | - Jian Wang
- Department of Medical Genetics and Molecular Diagnostic Laboratory, Shanghai Children's Medical Center, Shanghai Jiaotong University School of Medicine, 1678 Dongfang Road, Shanghai, 200127, People's Republic of China.
| | - Tingting Yu
- Department of Medical Genetics and Molecular Diagnostic Laboratory, Shanghai Children's Medical Center, Shanghai Jiaotong University School of Medicine, 1678 Dongfang Road, Shanghai, 200127, People's Republic of China.
| |
Collapse
|
17
|
Groeneweg FL, Trattnig C, Kuhse J, Nawrotzki RA, Kirsch J. Gephyrin: a key regulatory protein of inhibitory synapses and beyond. Histochem Cell Biol 2018; 150:489-508. [DOI: 10.1007/s00418-018-1725-2] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/07/2018] [Indexed: 12/26/2022]
|
18
|
Zhou R, Jiang G, Tian X, Wang X. Progress in the molecular mechanisms of genetic epilepsies using patient-induced pluripotent stem cells. Epilepsia Open 2018; 3:331-339. [PMID: 30187003 PMCID: PMC6119748 DOI: 10.1002/epi4.12238] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/25/2018] [Indexed: 12/29/2022] Open
Abstract
Research findings on the molecular mechanisms of epilepsy almost always originate from animal experiments, and the development of induced pluripotent stem cell (iPSC) technology allows the use of human cells with genetic defects for studying the molecular mechanisms of genetic epilepsy (GE) for the first time. With iPSC technology, terminally differentiated cells collected from GE patients with specific genetic etiologies can be differentiated into many relevant cell subtypes that carry all of the GE patient's genetic information. iPSCs have opened up a new research field involving the pathogenesis of GE. Using this approach, studies have found that gene mutations induce GE by altering the balance between neuronal excitation and inhibition, which is associated. among other factors, with neuronal developmental disturbances, ion channel abnormalities, and synaptic dysfunction. Simultaneously, astrocyte activation, mitochondrial dysfunction, and abnormal signaling pathway activity are also important factors in the molecular mechanisms of GE.
Collapse
Affiliation(s)
- Ruijiao Zhou
- Department of Neurology the First Affiliated Hospital of Chongqing Medical University Chongqing Key Laboratory of Neurology Chongqing China
| | - Guohui Jiang
- Department of Neurology Institute of Neurological Diseases Affiliated Hospital of North Sichuan Medical College Nanchong China
| | - Xin Tian
- Department of Neurology the First Affiliated Hospital of Chongqing Medical University Chongqing Key Laboratory of Neurology Chongqing China
| | - Xuefeng Wang
- Department of Neurology the First Affiliated Hospital of Chongqing Medical University Chongqing Key Laboratory of Neurology Chongqing China
| |
Collapse
|
19
|
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
|
20
|
Joensuu M, Lanoue V, Hotulainen P. Dendritic spine actin cytoskeleton in autism spectrum disorder. Prog Neuropsychopharmacol Biol Psychiatry 2018; 84:362-381. [PMID: 28870634 DOI: 10.1016/j.pnpbp.2017.08.023] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 08/21/2017] [Accepted: 08/30/2017] [Indexed: 01/01/2023]
Abstract
Dendritic spines are small actin-rich protrusions from neuronal dendrites that form the postsynaptic part of most excitatory synapses. Changes in the shape and size of dendritic spines correlate with the functional changes in excitatory synapses and are heavily dependent on the remodeling of the underlying actin cytoskeleton. Recent evidence implicates synapses at dendritic spines as important substrates of pathogenesis in neuropsychiatric disorders, including autism spectrum disorder (ASD). Although synaptic perturbations are not the only alterations relevant for these diseases, understanding the molecular underpinnings of the spine and synapse pathology may provide insight into their etiologies and could reveal new drug targets. In this review, we will discuss recent findings of defective actin regulation in dendritic spines associated with ASD.
Collapse
Affiliation(s)
- Merja Joensuu
- Minerva Foundation Institute for Medical Research, 00290 Helsinki, Finland; Clem Jones Centre for Ageing Dementia Research, The University of Queensland, Brisbane, Queensland 4072, Australia; Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Vanessa Lanoue
- Clem Jones Centre for Ageing Dementia Research, The University of Queensland, Brisbane, Queensland 4072, Australia; Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Pirta Hotulainen
- Minerva Foundation Institute for Medical Research, 00290 Helsinki, Finland.
| |
Collapse
|
21
|
Abstract
The eukaryotic initiation factor 3 (eIF3) is one of the most complex translation initiation factors in mammalian cells, consisting of several subunits (eIF3a to eIF3m). It is crucial in translation initiation and termination, and in ribosomal recycling. Accordingly, deregulated eIF3 expression is associated with different pathological conditions, including cancer. In this manuscript, we discuss the interactome and function of each subunit of the human eIF3 complex. Furthermore, we review how altered levels of eIF3 subunits correlate with neurodegenerative disorders and cancer onset and development; in addition, we evaluate how such misregulation may also trigger infection cascades. A deep understanding of the molecular mechanisms underlying eIF3 role in human disease is essential to develop new eIF3-targeted therapeutic approaches and thus, overcome such conditions.
Collapse
Affiliation(s)
- Andreia Gomes-Duarte
- a Department of Human Genetics , Instituto Nacional de Saúde Doutor Ricardo Jorge , Lisbon , Portugal.,b Gene Expression and Regulation Group, Biosystems & Integrative Sciences Institute (BioISI), Faculdade de Ciências , Universidade de Lisboa , Lisbon , Portugal
| | - Rafaela Lacerda
- a Department of Human Genetics , Instituto Nacional de Saúde Doutor Ricardo Jorge , Lisbon , Portugal.,b Gene Expression and Regulation Group, Biosystems & Integrative Sciences Institute (BioISI), Faculdade de Ciências , Universidade de Lisboa , Lisbon , Portugal
| | - Juliane Menezes
- a Department of Human Genetics , Instituto Nacional de Saúde Doutor Ricardo Jorge , Lisbon , Portugal.,b Gene Expression and Regulation Group, Biosystems & Integrative Sciences Institute (BioISI), Faculdade de Ciências , Universidade de Lisboa , Lisbon , Portugal
| | - Luísa Romão
- a Department of Human Genetics , Instituto Nacional de Saúde Doutor Ricardo Jorge , Lisbon , Portugal.,b Gene Expression and Regulation Group, Biosystems & Integrative Sciences Institute (BioISI), Faculdade de Ciências , Universidade de Lisboa , Lisbon , Portugal
| |
Collapse
|
22
|
Wang JY, Zhou P, Wang J, Tang B, Su T, Liu XR, Li BM, Meng H, Shi YW, Yi YH, He N, Liao WP. ARHGEF9 mutations in epileptic encephalopathy/intellectual disability: toward understanding the mechanism underlying phenotypic variation. Neurogenetics 2017; 19:9-16. [PMID: 29130122 DOI: 10.1007/s10048-017-0528-2] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 10/25/2017] [Indexed: 01/01/2023]
Abstract
ARHGEF9 resides on Xq11.1 and encodes collybistin, which is crucial in gephyrin clustering and GABAA receptor localization. ARHGEF9 mutations have been identified in patients with heterogeneous phenotypes, including epilepsy of variable severity and intellectual disability. However, the mechanism underlying phenotype variation is unknown. Using next-generation sequencing, we identified a novel mutation, c.868C > T/p.R290C, which co-segregated with epileptic encephalopathy, and validated its association with epileptic encephalopathy. Further analysis revealed that all ARHGEF9 mutations were associated with intellectual disability, suggesting its critical role in psychomotor development. Three missense mutations in the PH domain were not associated with epilepsy, suggesting that the co-occurrence of epilepsy depends on the affected functional domains. Missense mutations with severe molecular alteration in the DH domain, or located in the DH-gephyrin binding region, or adjacent to the SH3-NL2 binding site were associated with severe epilepsy, implying that the clinical severity was potentially determined by alteration of molecular structure and location of mutations. Male patients with ARHGEF9 mutations presented more severe phenotypes than female patients, which suggests a gene-dose effect and supports the pathogenic role of ARHGEF9 mutations. This study highlights the role of molecular alteration in phenotype expression and facilitates evaluation of the pathogenicity of ARHGEF9 mutations in clinical practice.
Collapse
Affiliation(s)
- Jing-Yang Wang
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University Please check if the affiliations are presented correctly.The affiliations are presented correctly., Chang-Gang-Dong Road 250, Guangzhou, 510260, China
- Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, 510260, China
| | - Peng Zhou
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University Please check if the affiliations are presented correctly.The affiliations are presented correctly., Chang-Gang-Dong Road 250, Guangzhou, 510260, China
- Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, 510260, China
| | - Jie Wang
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University Please check if the affiliations are presented correctly.The affiliations are presented correctly., Chang-Gang-Dong Road 250, Guangzhou, 510260, China
- Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, 510260, China
| | - Bin Tang
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University Please check if the affiliations are presented correctly.The affiliations are presented correctly., Chang-Gang-Dong Road 250, Guangzhou, 510260, China
- Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, 510260, China
| | - Tao Su
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University Please check if the affiliations are presented correctly.The affiliations are presented correctly., Chang-Gang-Dong Road 250, Guangzhou, 510260, China
- Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, 510260, China
| | - Xiao-Rong Liu
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University Please check if the affiliations are presented correctly.The affiliations are presented correctly., Chang-Gang-Dong Road 250, Guangzhou, 510260, China
- Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, 510260, China
| | - Bing-Mei Li
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University Please check if the affiliations are presented correctly.The affiliations are presented correctly., Chang-Gang-Dong Road 250, Guangzhou, 510260, China
- Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, 510260, China
| | - Heng Meng
- Department of Neurology, The First Affiliated Hospital of Jinan University, Guangdong, 510630, China
- Clinical Neuroscience Institute of Jinan University, Guangdong, 510630, China
| | - Yi-Wu Shi
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University Please check if the affiliations are presented correctly.The affiliations are presented correctly., Chang-Gang-Dong Road 250, Guangzhou, 510260, China
- Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, 510260, China
| | - Yong-Hong Yi
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University Please check if the affiliations are presented correctly.The affiliations are presented correctly., Chang-Gang-Dong Road 250, Guangzhou, 510260, China
- Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, 510260, China
| | - Na He
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University Please check if the affiliations are presented correctly.The affiliations are presented correctly., Chang-Gang-Dong Road 250, Guangzhou, 510260, China.
- Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, 510260, China.
| | - Wei-Ping Liao
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University Please check if the affiliations are presented correctly.The affiliations are presented correctly., Chang-Gang-Dong Road 250, Guangzhou, 510260, China.
- Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, 510260, China.
| |
Collapse
|
23
|
The phenotypic spectrum of ARHGEF9 includes intellectual disability, focal epilepsy and febrile seizures. J Neurol 2017. [DOI: 10.1007/s00415-017-8539-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
|
24
|
Fekete CD, Goz RU, Dinallo S, Miralles CP, Chiou TT, Bear J, Fiondella CG, LoTurco JJ, De Blas AL. In vivo transgenic expression of collybistin in neurons of the rat cerebral cortex. J Comp Neurol 2016; 525:1291-1311. [PMID: 27804142 DOI: 10.1002/cne.24137] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Revised: 10/18/2016] [Accepted: 10/19/2016] [Indexed: 01/12/2023]
Abstract
Collybistin (CB) is a guanine nucleotide exchange factor selectively localized to γ-aminobutyric acid (GABA)ergic and glycinergic postsynapses. Active CB interacts with gephyrin, inducing the submembranous clustering and the postsynaptic accumulation of gephyrin, which is a scaffold protein that recruits GABAA receptors (GABAA Rs) at the postsynapse. CB is expressed with or without a src homology 3 (SH3) domain. We have previously reported the effects on GABAergic synapses of the acute overexpression of CBSH3- or CBSH3+ in cultured hippocampal (HP) neurons. In the present communication, we are studying the effects on GABAergic synapses after chronic in vivo transgenic expression of CB2SH3- or CB2SH3+ in neurons of the adult rat cerebral cortex. The embryonic precursors of these cortical neurons were in utero electroporated with CBSH3- or CBSH3+ DNAs, migrated to the appropriate cortical layer, and became integrated in cortical circuits. The results show that: 1) the strength of inhibitory synapses in vivo can be enhanced by increasing the expression of CB in neurons; and 2) there are significant differences in the results between in vivo and in culture studies. J. Comp. Neurol. 525:1291-1311, 2017. © 2016 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Christopher D Fekete
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut, 06269
| | - Roman U Goz
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut, 06269
| | - Sean Dinallo
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut, 06269
| | - Celia P Miralles
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut, 06269
| | - Tzu-Ting Chiou
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut, 06269
| | - John Bear
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut, 06269
| | - Christopher G Fiondella
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut, 06269
| | - Joseph J LoTurco
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut, 06269
| | - Angel L De Blas
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut, 06269
| |
Collapse
|
25
|
Bhat G, LaGrave D, Millson A, Herriges J, Lamb AN, Matalon R. Xq11.1-11.2 deletion involving ARHGEF9 in a girl with autism spectrum disorder. Eur J Med Genet 2016; 59:470-3. [DOI: 10.1016/j.ejmg.2016.05.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 05/12/2016] [Accepted: 05/24/2016] [Indexed: 10/21/2022]
|
26
|
Receptor tyrosine kinase EphA7 is required for interneuron connectivity at specific subcellular compartments of granule cells. Sci Rep 2016; 6:29710. [PMID: 27405707 PMCID: PMC4942821 DOI: 10.1038/srep29710] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Accepted: 06/21/2016] [Indexed: 01/12/2023] Open
Abstract
Neuronal transmission is regulated by the local circuitry which is composed of principal neurons targeted at different subcellular compartments by a variety of interneurons. However, mechanisms that contribute to the subcellular localisation and maintenance of GABAergic interneuron terminals are poorly understood. Stabilization of GABAergic synapses depends on clustering of the postsynaptic scaffolding protein gephyrin and its interaction with the guanine nucleotide exchange factor collybistin. Lentiviral knockdown experiments in adult rats indicated that the receptor tyrosine kinase EphA7 is required for the stabilisation of basket cell terminals on proximal dendritic and somatic compartments of granular cells of the dentate gyrus. EphA7 deficiency and concomitant destabilisation of GABAergic synapses correlated with impaired long-term potentiation and reduced hippocampal learning. Reduced GABAergic innervation may be explained by an impact of EphA7 on gephyrin clustering. Overexpression or ephrin stimulation of EphA7 induced gephyrin clustering dependent on the mechanistic target of rapamycin (mTOR) which is an interaction partner of gephyrin. Gephyrin interactions with mTOR become released after mTOR activation while enhanced interaction with the guanine nucleotide exchange factor collybistin was observed in parallel. In conclusion, EphA7 regulates gephyrin clustering and the maintenance of inhibitory synaptic connectivity via mTOR signalling.
Collapse
|
27
|
Long P, May MM, James VM, Grannò S, Johnson JP, Tarpey P, Stevenson RE, Harvey K, Schwartz CE, Harvey RJ. Missense Mutation R338W in ARHGEF9 in a Family with X-linked Intellectual Disability with Variable Macrocephaly and Macro-Orchidism. Front Mol Neurosci 2016; 8:83. [PMID: 26834553 PMCID: PMC4719118 DOI: 10.3389/fnmol.2015.00083] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Accepted: 12/14/2015] [Indexed: 11/13/2022] Open
Abstract
Non-syndromal X-linked intellectual disability (NS-XLID) represents a broad group of clinical disorders in which ID is the only clinically consistent manifestation. Although in many cases either chromosomal linkage data or knowledge of the >100 existing XLID genes has assisted mutation discovery, the underlying cause of disease remains unresolved in many families. We report the resolution of a large family (K8010) with NS-XLID, with variable macrocephaly and macro-orchidism. Although a previous linkage study had mapped the locus to Xq12-q21, this region contained too many candidate genes to be analyzed using conventional approaches. However, X-chromosome exome sequencing, bioinformatics analysis and segregation analysis revealed a novel missense mutation (c.1012C>T; p.R338W) in ARHGEF9. This gene encodes collybistin (CB), a neuronal GDP-GTP exchange factor previously implicated in several cases of XLID, as well as clustering of gephyrin and GABAA receptors at inhibitory synapses. Molecular modeling of the CB R338W substitution revealed that this change results in the substitution of a long electropositive side-chain with a large non-charged hydrophobic side-chain. The R338W change is predicted to result in clashes with adjacent amino acids (K363 and N335) and disruption of electrostatic potential and local folding of the PH domain, which is known to bind phosphatidylinositol-3-phosphate (PI3P/PtdIns-3-P). Consistent with this finding, functional assays revealed that recombinant CB CB2SH3- (R338W) was deficient in PI3P binding and was not able to translocate EGFP-gephyrin to submembrane microaggregates in an in vitro clustering assay. Taken together, these results suggest that the R338W mutation in ARHGEF9 is the underlying cause of NS-XLID in this family.
Collapse
Affiliation(s)
- Philip Long
- Department of Pharmacology, UCL School of Pharmacy London, UK
| | - Melanie M May
- JC Self Research Institute, Greenwood Genetic Center Greenwood, SC, USA
| | | | - Simone Grannò
- Department of Pharmacology, UCL School of Pharmacy London, UK
| | - John P Johnson
- Department of Medical Genetics, Shodair Children's Hospital Helena, MT, USA
| | - Patrick Tarpey
- Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus Hinxton, UK
| | - Roger E Stevenson
- JC Self Research Institute, Greenwood Genetic Center Greenwood, SC, USA
| | - Kirsten Harvey
- Department of Pharmacology, UCL School of Pharmacy London, UK
| | | | - Robert J Harvey
- Department of Pharmacology, UCL School of Pharmacy London, UK
| |
Collapse
|