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Uzunova G, Hollander E, Shepherd J. The role of ionotropic glutamate receptors in childhood neurodevelopmental disorders: autism spectrum disorders and fragile x syndrome. Curr Neuropharmacol 2014; 12:71-98. [PMID: 24533017 PMCID: PMC3915351 DOI: 10.2174/1570159x113116660046] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Revised: 08/20/2013] [Accepted: 09/25/2013] [Indexed: 12/20/2022] Open
Abstract
Autism spectrum disorder (ASD) and Fragile X syndrome (FXS) are relatively common childhood neurodevelopmental disorders with increasing incidence in recent years. They are currently accepted as disorders of the synapse with alterations in different forms of synaptic communication and neuronal network connectivity. The major excitatory neurotransmitter system in brain, the glutamatergic system, is implicated in learning and memory, synaptic plasticity, neuronal development. While much attention is attributed to the role of metabotropic glutamate receptors in ASD and FXS, studies indicate that the ionotropic glutamate receptors (iGluRs) and their regulatory proteins are also altered in several brain regions. Role of iGluRs in the neurobiology of ASD and FXS is supported by a weight of evidence that ranges from human genetics to in vitro cultured neurons. In this review we will discuss clinical, molecular, cellular and functional changes in NMDA, AMPA and kainate receptors and the synaptic proteins that regulate them in the context of ASD and FXS. We will also discuss the significance for the development of translational biomarkers and treatments for the core symptoms of ASD and FXS.
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Affiliation(s)
- Genoveva Uzunova
- Autism and Obsessive Compulsive Spectrum Program, Department of Psychiatry, Montefiore Medical Center, Albert Einstein College of Medicine, 111 East 210th St, Bronx, New York 10467-2490
| | - Eric Hollander
- Autism and Obsessive Compulsive Spectrum Program, Department of Psychiatry, Montefiore Medical Center, Albert Einstein College of Medicine, 111 East 210th St, Bronx, New York 10467-2490
| | - Jason Shepherd
- Department of Neurobiology and Anatomy, University of Utah School of Medicine, 531A Wintrobe, 20N 1900 E, Salt Lake City, Utah 84132
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152
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D'Antoni S, Spatuzza M, Bonaccorso CM, Musumeci SA, Ciranna L, Nicoletti F, Huber KM, Catania MV. Dysregulation of group-I metabotropic glutamate (mGlu) receptor mediated signalling in disorders associated with Intellectual Disability and Autism. Neurosci Biobehav Rev 2014; 46 Pt 2:228-41. [PMID: 24548786 DOI: 10.1016/j.neubiorev.2014.02.003] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Revised: 01/13/2014] [Accepted: 02/06/2014] [Indexed: 12/11/2022]
Abstract
Activation of group-I metabotropic glutamate receptors, mGlu1 and mGlu5, triggers a variety of signalling pathways in neurons and glial cells, which are differently implicated in synaptic plasticity. The earliest and much of key studies discovered abnormal mGlu5 receptor function in Fragile X syndrome (FXS) mouse models which then motivated more recent work that finds mGlu5 receptor dysfunction in related disorders such as intellectual disability (ID), obsessive-compulsive disorder (OCD) and autism. Therefore, mGlu1/5 receptor dysfunction may represent a common aetiology of these complex diseases. Furthermore, many studies have focused on dysregulation of mGlu5 signalling to synaptic protein synthesis. However, emerging evidence finds abnormal mGlu5 receptor interactions with its scaffolding proteins in FXS which results in mGlu5 receptor dysfunction and phenotypes independent of signalling to protein synthesis. Finally, both an increased and reduced mGlu5 functioning seem to be associated with ID and autism spectrum disorders, with important consequences for potential treatment of these developmental disorders.
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Affiliation(s)
- Simona D'Antoni
- Institute of Neurological Sciences, the National Research Council of Italy (CNR), Catania, Italy
| | - Michela Spatuzza
- Institute of Neurological Sciences, the National Research Council of Italy (CNR), Catania, Italy
| | | | | | - Lucia Ciranna
- Department of Biomedical Sciences, section of Physiology, University of Catania, Italy
| | - Ferdinando Nicoletti
- IRCCS Neuromed, Pozzilli (IS), Italy; University of Rome La Sapienza, Rome, Italy
| | - Kimberly M Huber
- University of Texas Southwestern Medical Center, Department of Neuroscience, Dallas, TX 75390-9111, USA
| | - Maria Vincenza Catania
- Institute of Neurological Sciences, the National Research Council of Italy (CNR), Catania, Italy; IRCCS Oasi Maria SS, Troina (EN), Italy.
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153
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Braat S, Kooy RF. Fragile X syndrome neurobiology translates into rational therapy. Drug Discov Today 2014; 19:510-9. [PMID: 24508819 DOI: 10.1016/j.drudis.2014.01.013] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Revised: 01/19/2014] [Accepted: 01/27/2014] [Indexed: 12/29/2022]
Abstract
Causal genetic defects have been identified for various neurodevelopmental disorders. A key example in this respect is fragile X syndrome, one of the most frequent genetic causes of intellectual disability and autism. Since the discovery of the causal gene, insights into the underlying pathophysiological mechanisms have increased exponentially. Over the past years, defects were discovered in pathways that are potentially amendable by pharmacological treatment. These findings have inspired the initiation of clinical trials in patients. The targeted pathways converge in part with those of related neurodevelopmental disorders raising hopes that the treatments developed for this specific disorder might be more broadly applicable.
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Affiliation(s)
- Sien Braat
- Department of Medical Genetics, University of Antwerp, Prins Boudewijnlaan 43, Antwerp, Belgium
| | - R Frank Kooy
- Department of Medical Genetics, University of Antwerp, Prins Boudewijnlaan 43, Antwerp, Belgium.
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154
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Franklin AV, King MK, Palomo V, Martinez A, McMahon LL, Jope RS. Glycogen synthase kinase-3 inhibitors reverse deficits in long-term potentiation and cognition in fragile X mice. Biol Psychiatry 2014; 75:198-206. [PMID: 24041505 PMCID: PMC3874248 DOI: 10.1016/j.biopsych.2013.08.003] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Revised: 07/30/2013] [Accepted: 08/01/2013] [Indexed: 11/30/2022]
Abstract
BACKGROUND Identifying feasible therapeutic interventions is crucial for ameliorating the intellectual disability and other afflictions of fragile X syndrome (FXS), the most common inherited cause of intellectual disability and autism. Hippocampal glycogen synthase kinase-3 (GSK3) is hyperactive in the mouse model of FXS (FX mice), and hyperactive GSK3 promotes locomotor hyperactivity and audiogenic seizure susceptibility in FX mice, raising the possibility that specific GSK3 inhibitors may improve cognitive processes. METHODS We tested if specific GSK3 inhibitors improve deficits in N-methyl-D-aspartate receptor-dependent long-term potentiation at medial perforant path synapses onto dentate granule cells and dentate gyrus-dependent cognitive behavioral tasks. RESULTS GSK3 inhibitors completely rescued deficits in long-term potentiation at medial perforant path-dentate granule cells synapses in FX mice. Furthermore, synaptosomes from the dentate gyrus of FX mice displayed decreased inhibitory serine-phosphorylation of GSK3β compared with wild-type littermates. The potential therapeutic utility of GSK3 inhibitors was further tested on dentate gyrus-dependent cognitive behaviors. In vivo administration of GSK3 inhibitors completely reversed impairments in several cognitive tasks in FX mice, including novel object detection, coordinate and categorical spatial processing, and temporal ordering for visual objects. CONCLUSIONS These findings establish that synaptic plasticity and cognitive deficits in FX mice can be improved by intervention with inhibitors of GSK3, which may prove therapeutically beneficial in FXS.
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Affiliation(s)
- Aimee V. Franklin
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Margaret K. King
- Departments of Psychiatry and Behavioral Sciences and Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL 33136
| | - Valle Palomo
- Instituto Quimica Medica-CSIC, Juan de la Cierva 3, 28006 Madrid, Spain
| | - Ana Martinez
- Instituto Quimica Medica-CSIC, Juan de la Cierva 3, 28006 Madrid, Spain
| | - Lori L. McMahon
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Richard S. Jope
- Departments of Psychiatry and Behavioral Sciences and Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, FL 33136,Corresponding author: Richard S. Jope, Miller School of Medicine, University of Miami, 1011 NW 15th Street, Gautier Building room 416, Miami, Florida 33136, phone: 305-243-0262,
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155
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Bhattacharya A, Klann E. (Li+)ghting the way for a treatment for cognitive impairments in fragile X syndrome. Biol Psychiatry 2014; 75:175-6. [PMID: 24370350 DOI: 10.1016/j.biopsych.2013.11.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Accepted: 11/12/2013] [Indexed: 11/25/2022]
Affiliation(s)
| | - Eric Klann
- Center for Neural Science, New York University, New York, New York.
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156
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Maurin T, Zongaro S, Bardoni B. Fragile X Syndrome: from molecular pathology to therapy. Neurosci Biobehav Rev 2014; 46 Pt 2:242-55. [PMID: 24462888 DOI: 10.1016/j.neubiorev.2014.01.006] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Revised: 01/12/2014] [Accepted: 01/14/2014] [Indexed: 02/09/2023]
Abstract
Fragile X Syndrome (FXS) is the most common form of inherited intellectual disability due to the silencing of the FMR1 gene encoding FMRP (Fragile X Mental Retardation Protein), an RNA-binding protein involved in different steps of RNA metabolism. Of particular interest is the key role of FMRP in translational regulation. Since the first functional characterizations of FMRP, its role has been underlined by its association with actively translating polyribosomes. Furthermore, a plethora of mRNA targets of FMRP have been identified. In the absence of FMRP the deregulation of translation/transport/stability of these mRNAs has a cascade effect on many pathways, resulting into the final phenotype. We review here a set of targets of FMRP (mRNAs and proteins) that may have an impact on the FXS phenotype by deregulating some key cellular processes, such as translation, cytoskeleton remodeling and oxidative stress. The manipulation of these abnormal pathways by specific drugs may represent new therapeutic opportunities for FXS patients.
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Affiliation(s)
- Thomas Maurin
- Institute of Molecular and Cellular Pharmacology, CNRS UMR7275, University of Nice Sophia Antipolis, Route des Lucioles, 06560 Valbonne, France
| | - Samantha Zongaro
- Institute of Molecular and Cellular Pharmacology, CNRS UMR7275, University of Nice Sophia Antipolis, Route des Lucioles, 06560 Valbonne, France
| | - Barbara Bardoni
- Institute of Molecular and Cellular Pharmacology, CNRS UMR7275, University of Nice Sophia Antipolis, Route des Lucioles, 06560 Valbonne, France.
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157
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Thomazeau A, Lassalle O, Iafrati J, Souchet B, Guedj F, Janel N, Chavis P, Delabar J, Manzoni OJ. Prefrontal deficits in a murine model overexpressing the down syndrome candidate gene dyrk1a. J Neurosci 2014; 34:1138-47. [PMID: 24453307 PMCID: PMC3953590 DOI: 10.1523/jneurosci.2852-13.2014] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Revised: 11/29/2013] [Accepted: 12/06/2013] [Indexed: 12/16/2022] Open
Abstract
The gene Dyrk1a is the mammalian ortholog of Drosophila minibrain. Dyrk1a localizes in the Down syndrome (DS) critical region of chromosome 21q22.2 and is a major candidate for the behavioral and neuronal abnormalities associated with DS. PFC malfunctions are a common denominator in several neuropsychiatric diseases, including DS, but the contribution of DYRK1A in PFC dysfunctions, in particular the synaptic basis for impairments of executive functions reported in DS patients, remains obscure. We quantified synaptic plasticity, biochemical synaptic markers, and dendritic morphology of deep layer pyramidal PFC neurons in adult mBACtgDyrk1a transgenic mice that overexpress Dyrk1a under the control of its own regulatory sequences. We found that overexpression of Dyrk1a largely increased the number of spines on oblique dendrites of pyramidal neurons, as evidenced by augmented spine density, higher PSD95 protein levels, and larger miniature EPSCs. The dendritic alterations were associated with anomalous NMDAR-mediated long-term potentiation and accompanied by a marked reduction in the pCaMKII/CaMKII ratio in mBACtgDyrk1a mice. Retrograde endocannabinoid-mediated long-term depression (eCB-LTD) was ablated in mBACtgDyrk1a mice. Administration of green tea extracts containing epigallocatechin 3-gallate, a potent DYRK1A inhibitor, to adult mBACtgDyrk1a mice normalized long-term potentiation and spine anomalies but not eCB-LTD. However, inhibition of the eCB deactivating enzyme monoacylglycerol lipase normalized eCB-LTD in mBACtgDyrk1a mice. These data shed light on previously undisclosed participation of DYRK1A in adult PFC dendritic structures and synaptic plasticity. Furthermore, they suggest its involvement in DS-related endophenotypes and identify new potential therapeutic strategies.
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Affiliation(s)
- Aurore Thomazeau
- Institut National de la Santé et de la Recherche Médicale U901, Marseille, 13009, France, Université Aix-Marseille UMR S901, Marseille, 13009, France, INMED, Marseille, 13009, France, and Université Paris Diderot, Sorbonne Paris Cité, Adaptive Functional Biology, EAC Centre National de la Recherche Scientifique 4413, Paris, 75205, France
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158
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Navakkode S, Korte M. Pharmacological activation of CB1 receptor modulates long term potentiation by interfering with protein synthesis. Neuropharmacology 2014; 79:525-33. [PMID: 24412673 DOI: 10.1016/j.neuropharm.2013.11.018] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Revised: 11/04/2013] [Accepted: 11/21/2013] [Indexed: 12/30/2022]
Abstract
Cognitive impairment is one of the most important side effects associated with cannabis drug abuse, as well as the serious issue concerning the therapeutic use of cannabinoids. Cognitive impairments and neuropsychiatric symptoms are caused by early synaptic dysfunctions, such as loss of synaptic connections in different brain structures including the hippocampus, a region that is believed to play an important role in certain forms of learning and memory. We report here that metaplastic priming of synapses with a cannabinoid type 1 receptor (CB1 receptor) agonist, WIN55,212-2 (WIN55), significantly impaired long-term potentiation in the apical dendrites of CA1 pyramidal neurons. Interestingly, the CB1 receptor exerts its effect by altering the balance of protein synthesis machinery towards higher protein production. Therefore the activation of CB1 receptor, prior to strong tetanization, increased the propensity to produce new proteins. In addition, WIN55 priming resulted in the expression of late-LTP in a synaptic input that would have normally expressed early-LTP, thus confirming that WIN55 priming of LTP induces new synthesis of plasticity-related proteins. Furthermore, in addition to the effects on protein translation, WIN55 also induced synaptic deficits due to the ability of CB1 receptors to inhibit the release of acetylcholine, mediated by both muscarinic and nicotinic acetylcholine receptors. Taken together this supports the notion that the modulation of cholinergic activity by CB1 receptor activation is one mechanism that regulates the synthesis of plasticity-related proteins.
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Affiliation(s)
- Sheeja Navakkode
- Zoology Institute, Division of Cellular Neurobiology, TU, Braunschweig D-38106 Germany
| | - Martin Korte
- Zoology Institute, Division of Cellular Neurobiology, TU, Braunschweig D-38106 Germany.
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159
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Carbonetto S. A blueprint for research on Shankopathies: a view from research on autism spectrum disorder. Dev Neurobiol 2013; 74:85-112. [PMID: 24218108 DOI: 10.1002/dneu.22150] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Accepted: 11/06/2013] [Indexed: 01/21/2023]
Abstract
Autism spectrum disorders (ASD) are associated with mutations in a host of genes including a number that function in synaptic transmission. Phelan McDermid syndrome involves mutations in SHANK3 which encodes a protein that forms a scaffold for glutamate receptors at the synapse. SHANK3 is one of the genes that underpins the synaptic hypothesis for ASD. We discuss this hypothesis with a view to the broader context of ASD and with special emphasis on highly penetrant genetic disorders including Shankopathies. We propose a blueprint for near and longer-term goals for fundamental and translational research on Shankopathies.
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Affiliation(s)
- Salvatore Carbonetto
- Centre for Research in Neuroscience, Department of Neurology, McGill University Health Centre, Montreal, Quebec, H3G1A4, Canada
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160
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Fonseca R. Asymmetrical synaptic cooperation between cortical and thalamic inputs to the amygdale. Neuropsychopharmacology 2013; 38:2675-87. [PMID: 23884343 PMCID: PMC3828539 DOI: 10.1038/npp.2013.178] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Revised: 07/14/2013] [Accepted: 07/17/2013] [Indexed: 02/06/2023]
Abstract
Fear conditioning, a form of associative learning is thought to involve the induction of an associative long-term potentiation of cortical and thalamic inputs to the lateral amygdala. Here, we show that stimulation of the thalamic input can reinforce a transient form of plasticity (E-LTP) induced by weak stimulation of the cortical inputs. This synaptic cooperation occurs within a time window of 30 min, suggesting that synaptic integration at amygdala synapses can occur within large time windows. Interestingly, we found that synaptic cooperation is not symmetrical. Reinforcement of a thalamic E-LTP by subsequent cortical stimulation is only observed within a shorter time window. We found that activation of endocannabinoid CB1 receptors is involved in the time restriction of thalamic and cortical synaptic cooperation in an activity-dependent manner. Our results support the hypothesis that synaptic cooperation can underlie associative learning and that synaptic tagging and capture is a general mechanism in synaptic plasticity.
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Affiliation(s)
- Rosalina Fonseca
- Champalimaud Neuroscience Program at Gulbenkian Institute of Science, Oeiras, Portugal,Cellular and Systems Neuroscience, Gulbenkian Institute of Science, Rua da Quinta Grande, 6, Oeiras 2850 Portugal, Tel: +351 214 404 664, Fax: +351 214 407 970, E-mail:
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161
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mTOR complexes in neurodevelopmental and neuropsychiatric disorders. Nat Neurosci 2013; 16:1537-43. [PMID: 24165680 DOI: 10.1038/nn.3546] [Citation(s) in RCA: 264] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Accepted: 09/11/2013] [Indexed: 02/07/2023]
Abstract
The mechanistic target of rapamycin (mTOR) acts as a highly conserved signaling "hub" that integrates neuronal activity and a variety of synaptic inputs. mTOR is found in two functionally distinct complexes, mTORC1 and mTORC2, that crucially control long-term synaptic efficacy and memory storage. Dysregulation of mTOR signaling is associated with neurodevelopmental and neuropsychiatric disorders. In this Review, we describe the most recent advances in studies of mTOR signaling in the brain and the possible mechanisms underlying the many different functions of the mTOR complexes in neurological diseases. In addition, we discuss the medical relevance of these findings.
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162
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Fernández E, Rajan N, Bagni C. The FMRP regulon: from targets to disease convergence. Front Neurosci 2013; 7:191. [PMID: 24167470 PMCID: PMC3807044 DOI: 10.3389/fnins.2013.00191] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Accepted: 10/04/2013] [Indexed: 01/08/2023] Open
Abstract
The fragile X mental retardation protein (FMRP) is an RNA-binding protein that regulates mRNA metabolism. FMRP has been largely studied in the brain, where the absence of this protein leads to fragile X syndrome, the most frequent form of inherited intellectual disability. Since the identification of the FMRP gene in 1991, many studies have primarily focused on understanding the function/s of this protein. Hundreds of potential FMRP mRNA targets and several interacting proteins have been identified. Here, we report the identification of FMRP mRNA targets in the mammalian brain that support the key role of this protein during brain development and in regulating synaptic plasticity. We compared the genes from databases and genome-wide association studies with the brain FMRP transcriptome, and identified several FMRP mRNA targets associated with autism spectrum disorders, mood disorders and schizophrenia, showing a potential common pathway/s for these apparently different disorders.
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Affiliation(s)
- Esperanza Fernández
- Center for the Biology of Disease, Vlaams Institut voor Biotechnologie Leuven, Belgium ; Center for Human Genetics, Leuven Institute for Neuroscience and Disease, KU Leuven Leuven, Belgium
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163
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Pax6-Dependent Cortical Glutamatergic Neuronal Differentiation Regulates Autism-Like Behavior in Prenatally Valproic Acid-Exposed Rat Offspring. Mol Neurobiol 2013; 49:512-28. [DOI: 10.1007/s12035-013-8535-2] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Accepted: 08/15/2013] [Indexed: 12/19/2022]
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164
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Abstract
G-protein–coupled receptors (GPCRs) still offer enormous scope for new therapeutic targets. Currently marketed agents are dominated by those with activity at aminergic receptors and yet they account for only ~10% of the family. Progress up until now with other subfamilies, notably orphans, Family A/peptide, Family A/lipid, Family B, Family C, and Family F, has been, at best, patchy. This may be attributable to the heterogeneous nature of GPCRs, their endogenous ligands, and consequently their binding sites. Our appreciation of receptor similarity has arguably been too simplistic, and screening collections have not necessarily been well suited to identifying leads in new areas. Despite the relative shortage of high-quality tool molecules in a number of cases, there is an emerging, and increasingly substantial, body of evidence associating many as yet “undrugged” receptors with a very wide range of diseases. Significant advances in our understanding of receptor pharmacology and technical advances in screening, protein X-ray crystallography, and ligand design methods are paving the way for new successes in the area. Exploitation of allosteric mechanisms; alternative signaling pathways such as G12/13, Gβγ, and β-arrestin; the discovery of “biased” ligands; and the emergence of GPCR-protein complexes as potential drug targets offer scope for new and much improved drugs.
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165
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Singh SK, Eroglu C. Neuroligins provide molecular links between syndromic and nonsyndromic autism. Sci Signal 2013; 6:re4. [PMID: 23838185 DOI: 10.1126/scisignal.2004102] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Autism is a common and heritable neuropsychiatric disorder that can be categorized into two types: syndromic and nonsyndromic, the former of which are associated with other neurological disorders or syndromes. Molecular and functional links between syndromic and nonsyndromic autism genes were lacking until studies aimed at understanding the role of trans-synaptic adhesion molecule neuroligin, which is associated with nonsyndromic autism, provided important connections. Here, we integrate data from these studies into a model of how neuroligin functions to control synaptic connectivity in the central nervous system and how neuroligin dysfunction may participate in the pathophysiology of autism. Understanding the complex functional interactions between neuroligins and other autism-associated proteins at the synapse is crucial to understand the pathology of autism. This understanding might bring us closer to development of therapeutic approaches for autism.
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Affiliation(s)
- Sandeep K Singh
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA
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