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Domínguez-Sala E, Valdés-Sánchez L, Canals S, Reiner O, Pombero A, García-López R, Estirado A, Pastor D, Geijo-Barrientos E, Martínez S. Abnormalities in Cortical GABAergic Interneurons of the Primary Motor Cortex Caused by Lis1 (Pafah1b1) Mutation Produce a Non-drastic Functional Phenotype. Front Cell Dev Biol 2022; 10:769853. [PMID: 35309904 PMCID: PMC8924048 DOI: 10.3389/fcell.2022.769853] [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] [Received: 09/02/2021] [Accepted: 01/31/2022] [Indexed: 11/25/2022] Open
Abstract
LIS1 (PAFAH1B1) plays a major role in the developing cerebral cortex, and haploinsufficient mutations cause human lissencephaly type 1. We have studied morphological and functional properties of the cerebral cortex of mutant mice harboring a deletion in the first exon of the mouse Lis1 (Pafah1b1) gene, which encodes for the LisH domain. The Lis1/sLis1 animals had an overall unaltered cortical structure but showed an abnormal distribution of cortical GABAergic interneurons (those expressing calbindin, calretinin, or parvalbumin), which mainly accumulated in the deep neocortical layers. Interestingly, the study of the oscillatory activity revealed an apparent inability of the cortical circuits to produce correct activity patterns. Moreover, the fast spiking (FS) inhibitory GABAergic interneurons exhibited several abnormalities regarding the size of the action potentials, the threshold for spike firing, the time course of the action potential after-hyperpolarization (AHP), the firing frequency, and the frequency and peak amplitude of spontaneous excitatory postsynaptic currents (sEPSC’s). These morphological and functional alterations in the cortical inhibitory system characterize the Lis1/sLis1 mouse as a model of mild lissencephaly, showing a phenotype less drastic than the typical phenotype attributed to classical lissencephaly. Therefore, the results described in the present manuscript corroborate the idea that mutations in some regions of the Lis1 gene can produce phenotypes more similar to those typically described in schizophrenic and autistic patients and animal models.
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Affiliation(s)
- E Domínguez-Sala
- Instituto de Neurociencias, Universidad Miguel Hernández-CSIC, Sant Joan d'Alacant, Spain
| | - L Valdés-Sánchez
- Instituto de Neurociencias, Universidad Miguel Hernández-CSIC, Sant Joan d'Alacant, Spain
| | - S Canals
- Instituto de Neurociencias, Universidad Miguel Hernández-CSIC, Sant Joan d'Alacant, Spain
| | - O Reiner
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - A Pombero
- Instituto de Neurociencias, Universidad Miguel Hernández-CSIC, Sant Joan d'Alacant, Spain
| | - R García-López
- Instituto de Neurociencias, Universidad Miguel Hernández-CSIC, Sant Joan d'Alacant, Spain
| | - A Estirado
- Instituto de Neurociencias, Universidad Miguel Hernández-CSIC, Sant Joan d'Alacant, Spain
| | - D Pastor
- Instituto de Neurociencias, Universidad Miguel Hernández-CSIC, Sant Joan d'Alacant, Spain
| | - E Geijo-Barrientos
- Instituto de Neurociencias, Universidad Miguel Hernández-CSIC, Sant Joan d'Alacant, Spain
| | - S Martínez
- Instituto de Neurociencias, Universidad Miguel Hernández-CSIC, Sant Joan d'Alacant, Spain.,Centro de Investigación Biomédica en Red en Salud Mental CIBERSAM, Madrid, Spain
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Imaging of spine synapses using super-resolution microscopy. Anat Sci Int 2021; 96:343-358. [PMID: 33459976 DOI: 10.1007/s12565-021-00603-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 01/04/2021] [Indexed: 12/17/2022]
Abstract
Neuronal circuits in the neocortex and hippocampus are essential for higher brain functions such as motor learning and spatial memory. In the mammalian forebrain, most excitatory synapses of pyramidal neurons are formed on spines, which are tiny protrusions extending from the dendritic shaft. The spine contains specialized molecular machinery that regulates synaptic transmission and plasticity. Spine size correlates with the efficacy of synaptic transmission, and spine morphology affects signal transduction at the post-synaptic compartment. Plasticity-related changes in the structural and molecular organization of spine synapses are thought to underlie the cellular basis of learning and memory. Recent advances in super-resolution microscopy have revealed the molecular mechanisms of the nanoscale synaptic structures regulating synaptic transmission and plasticity in living neurons, which are difficult to investigate using electron microscopy alone. In this review, we summarize recent advances in super-resolution imaging of spine synapses and discuss the implications of nanoscale structures in the regulation of synaptic function, learning, and memory.
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An Essential Postdevelopmental Role for Lis1 in Mice. eNeuro 2018; 5:eN-NWR-0350-17. [PMID: 29404402 PMCID: PMC5797476 DOI: 10.1523/eneuro.0350-17.2018] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 01/13/2018] [Accepted: 01/17/2018] [Indexed: 12/15/2022] Open
Abstract
LIS1 mutations cause lissencephaly (LIS), a severe developmental brain malformation. Much less is known about its role in the mature nervous system. LIS1 regulates the microtubule motor cytoplasmic dynein 1 (dynein), and as LIS1 and dynein are both expressed in the adult nervous system, Lis1 could potentially regulate dynein-dependent processes such as axonal transport. We therefore knocked out Lis1 in adult mice using tamoxifen-induced, Cre-ER-mediated recombination. When an actin promoter was used to drive Cre-ER expression (Act-Cre-ER), heterozygous Lis1 knockout (KO) caused no obvious change in viability or behavior, despite evidence of widespread recombination by a Cre reporter three weeks after tamoxifen exposure. In contrast, homozygous Lis1 KO caused the rapid onset of neurological symptoms in both male and female mice. One tamoxifen-dosing regimen caused prominent recombination in the midbrain/hindbrain, PNS, and cardiac/skeletal muscle within a week; these mice developed severe symptoms in that time frame and were killed. A different tamoxifen regimen resulted in delayed recombination in midbrain/hindbrain, but not in other tissues, and also delayed the onset of symptoms. This indicates that Lis1 loss in the midbrain/hindbrain causes the severe phenotype. In support of this, brainstem regions known to house cardiorespiratory centers showed signs of axonal dysfunction in KO animals. Transport defects, neurofilament (NF) alterations, and varicosities were observed in axons in cultured DRG neurons from KO animals. Because no symptoms were observed when a cardiac specific Cre-ER promoter was used, we propose a vital role for Lis1 in autonomic neurons and implicate defective axonal transport in the KO phenotype.
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Dinday MT, Girskis KM, Lee S, Baraban SC, Hunt RF. PAFAH1B1 haploinsufficiency disrupts GABA neurons and synaptic E/I balance in the dentate gyrus. Sci Rep 2017; 7:8269. [PMID: 28811646 PMCID: PMC5557934 DOI: 10.1038/s41598-017-08809-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 07/12/2017] [Indexed: 11/18/2022] Open
Abstract
Hemizygous mutations in the human gene encoding platelet-activating factor acetylhydrolase IB subunit alpha (Pafah1b1), also called Lissencephaly-1, can cause classical lissencephaly, a severe malformation of cortical development. Children with this disorder suffer from deficits in neuronal migration, severe intellectual disability, intractable epilepsy and early death. While many of these features can be reproduced in Pafah1b1+/- mice, the impact of Pafah1b1+/- on the function of individual subpopulations of neurons and ultimately brain circuits is largely unknown. Here, we show tangential migration of young GABAergic interneurons into the developing hippocampus is slowed in Pafah1b1+/- mice. Mutant mice had a decreased density of parvalbumin- and somatostatin-positive interneurons in dentate gyrus, but no change in density of calretinin interneurons. Whole-cell patch-clamp recordings revealed increased excitatory and decreased inhibitory synaptic inputs onto granule cells of Pafah1b1+/- mice. Mutant animals developed spontaneous electrographic seizures, as well as long-term deficits in contextual memory. Our findings provide evidence of a dramatic shift in excitability in the dentate gyrus of Pafah1b1+/- mice that may contribute to epilepsy or cognitive impairments associated with lissencephaly.
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Affiliation(s)
- Matthew T Dinday
- Epilepsy Research Laboratory, Department of Neurological Surgery, University of California San Francisco, San Francisco, USA
| | - Kelly M Girskis
- Epilepsy Research Laboratory, Department of Neurological Surgery, University of California San Francisco, San Francisco, USA
| | - Sunyoung Lee
- Department of Anatomy & Neurobiology, University of California Irvine, California, USA
| | - Scott C Baraban
- Epilepsy Research Laboratory, Department of Neurological Surgery, University of California San Francisco, San Francisco, USA
| | - Robert F Hunt
- Department of Anatomy & Neurobiology, University of California Irvine, California, USA.
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OKABE S. Fluorescence imaging of synapse dynamics in normal circuit maturation and in developmental disorders. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2017; 93:483-497. [PMID: 28769018 PMCID: PMC5713177 DOI: 10.2183/pjab.93.029] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 05/26/2017] [Indexed: 06/07/2023]
Abstract
One of the most fundamental questions in neurobiology is how proper synaptic connections are established in the developing brain. Live-cell imaging of the synaptic structure and functional molecules can reveal the time course of synapse formation, molecular dynamics, and functional maturation. Using postsynaptic scaffolding proteins as a marker of synapse development, fluorescence time-lapse imaging revealed rapid formation of individual synapses that occurred within hours and their remodeling in culture preparations. In vivo two-photon excitation microscopy development enabled us to directly measure synapse turnover in living animals. In vivo synapse dynamics were suppressed in the adult rodent brain, but were maintained at a high level during the early postnatal period. This transition in synapse dynamics is biologically important and can be linked to the pathology of juvenile-onset psychiatric diseases. Indeed, the upregulation of synapse dynamics was observed in multiple mouse models of autism spectrum disorders. Fluorescence imaging of synapses provides new information regarding the physiology and pathology of neural circuit construction.
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Affiliation(s)
- Shigeo OKABE
- Department of Cellular Neurobiology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
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van de Willige D, Hoogenraad CC, Akhmanova A. Microtubule plus-end tracking proteins in neuronal development. Cell Mol Life Sci 2016; 73:2053-77. [PMID: 26969328 PMCID: PMC4834103 DOI: 10.1007/s00018-016-2168-3] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2015] [Revised: 02/04/2016] [Accepted: 02/22/2016] [Indexed: 11/28/2022]
Abstract
Regulation of the microtubule cytoskeleton is of pivotal importance for neuronal development and function. One such regulatory mechanism centers on microtubule plus-end tracking proteins (+TIPs): structurally and functionally diverse regulatory factors, which can form complex macromolecular assemblies at the growing microtubule plus-ends. +TIPs modulate important properties of microtubules including their dynamics and their ability to control cell polarity, membrane transport and signaling. Several neurodevelopmental and neurodegenerative diseases are associated with mutations in +TIPs or with misregulation of these proteins. In this review, we focus on the role and regulation of +TIPs in neuronal development and associated disorders.
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Affiliation(s)
- Dieudonnée van de Willige
- Cell Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands
| | - Casper C Hoogenraad
- Cell Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands.
| | - Anna Akhmanova
- Cell Biology, Faculty of Science, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands.
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Stouffer MA, Golden JA, Francis F. Neuronal migration disorders: Focus on the cytoskeleton and epilepsy. Neurobiol Dis 2015; 92:18-45. [PMID: 26299390 DOI: 10.1016/j.nbd.2015.08.003] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Revised: 08/05/2015] [Accepted: 08/12/2015] [Indexed: 01/28/2023] Open
Abstract
A wide spectrum of focal, regional, or diffuse structural brain abnormalities, collectively known as malformations of cortical development (MCDs), frequently manifest with intellectual disability (ID), epilepsy, and/or autistic spectrum disorder (ASD). As the acronym suggests, MCDs are perturbations of the normal architecture of the cerebral cortex and hippocampus. The pathogenesis of these disorders remains incompletely understood; however, one area that has provided important insights has been the study of neuronal migration. The amalgamation of human genetics and experimental studies in animal models has led to the recognition that common genetic causes of neurodevelopmental disorders, including many severe epilepsy syndromes, are due to mutations in genes regulating the migration of newly born post-mitotic neurons. Neuronal migration genes often, though not exclusively, code for proteins involved in the function of the cytoskeleton. Other cellular processes, such as cell division and axon/dendrite formation, which similarly depend on cytoskeletal functions, may also be affected. We focus here on how the susceptibility of the highly organized neocortex and hippocampus may be due to their laminar organization, which involves the tight regulation, both temporally and spatially, of gene expression, specialized progenitor cells, the migration of neurons over large distances and a birthdate-specific layering of neurons. Perturbations in neuronal migration result in abnormal lamination, neuronal differentiation defects, abnormal cellular morphology and circuit formation. Ultimately this results in disorganized excitatory and inhibitory activity leading to the symptoms observed in individuals with these disorders.
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Affiliation(s)
- Melissa A Stouffer
- INSERM UMRS 839, Paris, France; Sorbonne Universités, Université Pierre et Marie Curie, Paris, France; Institut du Fer à Moulin, Paris, France
| | - Jeffrey A Golden
- Department of Pathology, Brigham & Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, MA 02115, USA
| | - Fiona Francis
- INSERM UMRS 839, Paris, France; Sorbonne Universités, Université Pierre et Marie Curie, Paris, France; Institut du Fer à Moulin, Paris, France.
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Leclercq K, Afrikanova T, Langlois M, De Prins A, Buenafe OE, Rospo CC, Van Eeckhaut A, de Witte PAM, Crawford AD, Smolders I, Esguerra CV, Kaminski RM. Cross-species pharmacological characterization of the allylglycine seizure model in mice and larval zebrafish. Epilepsy Behav 2015; 45:53-63. [PMID: 25845493 DOI: 10.1016/j.yebeh.2015.03.019] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 03/16/2015] [Accepted: 03/17/2015] [Indexed: 01/29/2023]
Abstract
Treatment-resistant seizures affect about a third of patients suffering from epilepsy. To fulfill the need for new medications targeting treatment-resistant seizures, a number of rodent models offer the opportunity to assess a variety of potential treatment approaches. The use of such models, however, has proven to be time-consuming and labor-intensive. In this study, we performed pharmacological characterization of the allylglycine (AG) seizure model, a simple in vivo model for which we demonstrated a high level of treatment resistance. (d,l)-Allylglycine inhibits glutamic acid decarboxylase (GAD) - the key enzyme in γ-aminobutyric acid (GABA) biosynthesis - leading to GABA depletion, seizures, and neuronal damage. We performed a side-by-side comparison of mouse and zebrafish acute AG treatments including biochemical, electrographic, and behavioral assessments. Interestingly, seizure progression rate and GABA depletion kinetics were comparable in both species. Five mechanistically diverse antiepileptic drugs (AEDs) were used. Three out of the five AEDs (levetiracetam, phenytoin, and topiramate) showed only a limited protective effect (mainly mortality delay) at doses close to the TD50 (dose inducing motor impairment in 50% of animals) in mice. The two remaining AEDs (diazepam and sodium valproate) displayed protective activity against AG-induced seizures. Experiments performed in zebrafish larvae revealed behavioral AED activity profiles highly analogous to those obtained in mice. Having demonstrated cross-species similarities and limited efficacy of tested AEDs, we propose the use of AG in zebrafish as a convenient and high-throughput model of treatment-resistant seizures.
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Affiliation(s)
| | - Tatiana Afrikanova
- Laboratory for Molecular Biodiscovery, Department of Pharmaceutical and Pharmacological Sciences, University of Leuven, Leuven, Belgium
| | - Melanie Langlois
- Luxembourg Center for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - An De Prins
- Center for Neurosciences, C4N, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Brussels, Belgium
| | - Olivia E Buenafe
- Laboratory for Molecular Biodiscovery, Department of Pharmaceutical and Pharmacological Sciences, University of Leuven, Leuven, Belgium
| | - Chiara C Rospo
- Neuroscience TA, UCB Biopharma, Braine-l'Alleud, Belgium
| | - Ann Van Eeckhaut
- Luxembourg Center for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Peter A M de Witte
- Laboratory for Molecular Biodiscovery, Department of Pharmaceutical and Pharmacological Sciences, University of Leuven, Leuven, Belgium
| | - Alexander D Crawford
- Laboratory for Molecular Biodiscovery, Department of Pharmaceutical and Pharmacological Sciences, University of Leuven, Leuven, Belgium; Luxembourg Center for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Ilse Smolders
- Center for Neurosciences, C4N, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Brussels, Belgium
| | - Camila V Esguerra
- Laboratory for Molecular Biodiscovery, Department of Pharmaceutical and Pharmacological Sciences, University of Leuven, Leuven, Belgium; Chemical Neuroscience Group, Biotechnology Centre of Oslo, University of Oslo, Oslo, Norway.
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Dai X, Iwasaki H, Watanabe M, Okabe S. Dlx1 transcription factor regulates dendritic growth and postsynaptic differentiation through inhibition of neuropilin-2 and PAK3 expression. Eur J Neurosci 2013; 39:531-47. [DOI: 10.1111/ejn.12413] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2013] [Revised: 10/02/2013] [Accepted: 10/07/2013] [Indexed: 11/28/2022]
Affiliation(s)
- Xiaojing Dai
- Department of Cellular Neurobiology; Graduate School of Medicine; The University of Tokyo; Tokyo Japan
| | - Hirohide Iwasaki
- Department of Cellular Neurobiology; Graduate School of Medicine; The University of Tokyo; Tokyo Japan
| | - Masahiko Watanabe
- Department of Anatomy; Hokkaido University School of Medicine; Sapporo Japan
| | - Shigeo Okabe
- Department of Cellular Neurobiology; Graduate School of Medicine; The University of Tokyo; Tokyo Japan
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Reiner O, Sapir T. LIS1 functions in normal development and disease. Curr Opin Neurobiol 2013; 23:951-6. [PMID: 23973156 DOI: 10.1016/j.conb.2013.08.001] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Revised: 08/01/2013] [Accepted: 08/01/2013] [Indexed: 10/26/2022]
Abstract
LIS1, the first gene to be identified as involved in a neuronal migration disease, is a dosage-sensitive gene whose proper levels are required for multiple aspects of cortical development. Deletions in LIS1 result in a severe brain malformation, known as lissencephaly, whereas duplications delay brain development. LIS1 affects the proliferation of progenitors, spindle orientation and interkinetic nuclear movement in the ventricular zone, as well as nucleokinesis and migration of neurons. LIS1 regulatory interaction with the minus end directed molecular motor cytoplasmic dynein is the key for understanding its complex cellular functions. LIS1-dynein interaction decreases the average velocity of the molecular motor in vitro, shows more complex effects in vivo, and may be of importance in high-load transport especially in neurons.
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Affiliation(s)
- Orly Reiner
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 76100, Israel.
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Reiner O. LIS1 and DCX: Implications for Brain Development and Human Disease in Relation to Microtubules. SCIENTIFICA 2013; 2013:393975. [PMID: 24278775 PMCID: PMC3820303 DOI: 10.1155/2013/393975] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Accepted: 02/07/2013] [Indexed: 05/29/2023]
Abstract
Proper lamination of the cerebral cortex requires the orchestrated motility of neurons from their place of birth to their final destination. Improper neuronal migration may result in a wide range of diseases, including brain malformations, such as lissencephaly, mental retardation, schizophrenia, and autism. Ours and other studies have implicated that microtubules and microtubule-associated proteins play an important role in the regulation of neuronal polarization and neuronal migration. Here, we will review normal processes of brain development and neuronal migration, describe neuronal migration diseases, and will focus on the microtubule-associated functions of LIS1 and DCX, which participate in the regulation of neuronal migration and are involved in the human developmental brain disease, lissencephaly.
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Affiliation(s)
- Orly Reiner
- Department of Molecular Genetics, The Weizmann Institute of Science, 76100 Rehovot, Israel
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Sudarov A, Gooden F, Tseng D, Gan WB, Ross ME. Lis1 controls dynamics of neuronal filopodia and spines to impact synaptogenesis and social behaviour. EMBO Mol Med 2013; 5:591-607. [PMID: 23483716 PMCID: PMC3628102 DOI: 10.1002/emmm.201202106] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Revised: 01/29/2013] [Accepted: 01/31/2013] [Indexed: 11/08/2022] Open
Abstract
LIS1 (PAFAH1B1) mutation can impair neuronal migration, causing lissencephaly in humans. LIS1 loss is associated with dynein protein motor dysfunction, and disrupts the actin cytoskeleton through disregulated RhoGTPases. Recently, LIS1 was implicated as an important protein-network interaction node with high-risk autism spectrum disorder genes expressed in the synapse. How LIS1 might participate in this disorder has not been investigated. We examined the role of LIS1 in synaptogenesis of post-migrational neurons and social behaviour in mice. Two-photon imaging of actin-rich dendritic filopodia and spines in vivo showed significant reductions in elimination and turnover rates of dendritic protrusions of layer V pyramidal neurons in adolescent Lis1+/− mice. Lis1+/− filopodia on immature hippocampal neurons in vitro exhibited reduced density, length and RhoA dependent impaired dynamics compared to Lis1+/+. Moreover, Lis1+/− adolescent mice exhibited deficits in social interaction. Lis1 inactivation restricted to the postnatal hippocampus resulted in similar deficits in dendritic protrusion density and social interactions. Thus, LIS1 plays prominently in dendritic filopodia dynamics and spine turnover implicating reduced dendritic spine plasticity as contributing to developmental autistic-like behaviour.
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Affiliation(s)
- Anamaria Sudarov
- Brain and Mind Research Institute, Weill Medical College of Cornell University, New York, USA
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