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Aljuraysi S, Platt M, Pulix M, Poptani H, Plagge A. Microcephaly with a disproportionate hippocampal reduction, stem cell loss and neuronal lipid droplet symptoms in Trappc9 KO mice. Neurobiol Dis 2024; 192:106431. [PMID: 38331351 DOI: 10.1016/j.nbd.2024.106431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 01/23/2024] [Accepted: 02/04/2024] [Indexed: 02/10/2024] Open
Abstract
Mutations of the human TRAFFICKING PROTEIN PARTICLE COMPLEX SUBUNIT 9 (TRAPPC9) cause a neurodevelopmental disorder characterised by microcephaly and intellectual disability. Trappc9 constitutes a subunit specific to the intracellular membrane-associated TrappII complex. The TrappII complex interacts with Rab11 and Rab18, the latter being specifically associated with lipid droplets (LDs). Here we used non-invasive imaging to characterise Trappc9 knock-out (KO) mice as a model of the human hereditary disorder. KOs developed postnatal microcephaly with many grey and white matter regions being affected. In vivo magnetic resonance imaging (MRI) identified a disproportionately stronger volume reduction in the hippocampus, which was associated with a significant loss of Sox2-positive neural stem and progenitor cells. Diffusion tensor imaging indicated a reduced organisation or integrity of white matter areas. Trappc9 KOs displayed behavioural abnormalities in several tests related to exploration, learning and memory. Trappc9-deficient primary hippocampal neurons accumulated a larger LD volume per cell following Oleic Acid stimulation, and the coating of LDs by Perilipin-2 was much reduced. Additionally, Trappc9 KOs developed obesity, which was significantly more severe in females than in males. Our findings indicate that, beyond previously reported Rab11-related vesicle transport defects, dysfunctions in LD homeostasis might contribute to the neurobiological symptoms of Trappc9 deficiency.
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Affiliation(s)
- Sultan Aljuraysi
- Department of Biochemistry, Cell and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK; Department of Physiology, College of Medicine, King Saud University, Riyadh, Saudi Arabia
| | - Mark Platt
- Department of Molecular and Clinical Cancer Medicine, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK; Centre for Preclinical Imaging, University of Liverpool, Liverpool, UK
| | - Michela Pulix
- Department of Biochemistry, Cell and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK
| | - Harish Poptani
- Department of Molecular and Clinical Cancer Medicine, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK; Centre for Preclinical Imaging, University of Liverpool, Liverpool, UK.
| | - Antonius Plagge
- Department of Biochemistry, Cell and Systems Biology, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, UK; Centre for Preclinical Imaging, University of Liverpool, Liverpool, UK.
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Ghate PS, Vacharasin JM, Ward JA, Nowling D, Kay V, Cowen MH, Lawlor MK, McCord M, Xu H, Carmona E, Cheon SH, Chukwurah E, Walla M, Lizarraga SB. The Warburg micro syndrome protein RAB3GAP1 modulates neuronal morphogenesis and interacts with axon elongation end ER-Golgi trafficking factors. Neurobiol Dis 2023; 184:106215. [PMID: 37385458 DOI: 10.1016/j.nbd.2023.106215] [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: 08/03/2022] [Revised: 05/26/2023] [Accepted: 06/26/2023] [Indexed: 07/01/2023] Open
Abstract
RAB3GAP1 is GTPase activating protein localized to the ER and Golgi compartments. In humans, mutations in RAB3GAP1 are the most common cause of Warburg Micro syndrome, a neurodevelopmental disorder associated with intellectual disability, microcephaly, and agenesis of the corpus callosum. We found that downregulation of RAB3GAP1 leads to a reduction in neurite outgrowth and complexity in human stem cell derived neurons. To further define the cellular function of RAB3GAP1, we sought to identify novel interacting proteins. We used a combination of mass spectrometry, co-immunoprecipitation and colocalization analysis and identified two novel interactors of RAB3GAP1: the axon elongation factor Dedicator of cytokinesis 7 (DOCK7) and the TATA modulatory factor 1 (TMF1) a modulator of Endoplasmic Reticulum (ER) to Golgi trafficking. To define the relationship between RAB3GAP1 and its two novel interactors, we analyzed their localization to different subcellular compartments in neuronal and non-neuronal cells with loss of RAB3GAP1. We find that RAB3GAP1 is important for the sub-cellular localization of TMF1 and DOCK7 across different compartments of the Golgi and endoplasmic reticulum. In addition, we find that loss of function mutations in RAB3GAP1 lead to dysregulation of pathways that are activated in response to the cellular stress like ATF6, MAPK, and PI3-AKT signaling. In summary, our findings suggest a novel role for RAB3GAP1 in neurite outgrowth that could encompass the regulation of proteins that control axon elongation, ER-Golgi trafficking, as well as pathways implicated in response to cellular stress.
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Affiliation(s)
- Pankaj S Ghate
- Department of Biology and Center for Childhood Neurotherapeutics, University of South Carolina, Columbia, SC, United States of America
| | - Janay M Vacharasin
- Department of Biology and Center for Childhood Neurotherapeutics, University of South Carolina, Columbia, SC, United States of America
| | - Joseph A Ward
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI, United States of America; Center for Translational Neuroscience, Brown University, Providence, RI, United states of America
| | - Duncan Nowling
- Department of Biology and Center for Childhood Neurotherapeutics, University of South Carolina, Columbia, SC, United States of America
| | - Valerie Kay
- Department of Biology and Center for Childhood Neurotherapeutics, University of South Carolina, Columbia, SC, United States of America
| | - Mara H Cowen
- Department of Biology and Center for Childhood Neurotherapeutics, University of South Carolina, Columbia, SC, United States of America
| | - Mary-Kate Lawlor
- Department of Biology and Center for Childhood Neurotherapeutics, University of South Carolina, Columbia, SC, United States of America
| | - Mikayla McCord
- Department of Biology and Center for Childhood Neurotherapeutics, University of South Carolina, Columbia, SC, United States of America
| | - Hailey Xu
- Department of Biology and Center for Childhood Neurotherapeutics, University of South Carolina, Columbia, SC, United States of America
| | - Esteban Carmona
- Department of Biology and Center for Childhood Neurotherapeutics, University of South Carolina, Columbia, SC, United States of America
| | - Seon-Hye Cheon
- Department of Biology and Center for Childhood Neurotherapeutics, University of South Carolina, Columbia, SC, United States of America
| | - Evelyn Chukwurah
- Department of Biology and Center for Childhood Neurotherapeutics, University of South Carolina, Columbia, SC, United States of America
| | - Mike Walla
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC, United States of America
| | - Sofia B Lizarraga
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI, United States of America; Center for Translational Neuroscience, Brown University, Providence, RI, United states of America.
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Harding P, Cunha DL, Moosajee M. Animal and cellular models of microphthalmia. THERAPEUTIC ADVANCES IN RARE DISEASE 2021; 2:2633004021997447. [PMID: 37181112 PMCID: PMC10032472 DOI: 10.1177/2633004021997447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 02/02/2021] [Indexed: 05/16/2023]
Abstract
Microphthalmia is a rare developmental eye disorder affecting 1 in 7000 births. It is defined as a small (axial length ⩾2 standard deviations below the age-adjusted mean) underdeveloped eye, caused by disruption of ocular development through genetic or environmental factors in the first trimester of pregnancy. Clinical phenotypic heterogeneity exists amongst patients with varying levels of severity, and associated ocular and systemic features. Up to 11% of blind children are reported to have microphthalmia, yet currently no treatments are available. By identifying the aetiology of microphthalmia and understanding how the mechanisms of eye development are disrupted, we can gain a better understanding of the pathogenesis. Animal models, mainly mouse, zebrafish and Xenopus, have provided extensive information on the genetic regulation of oculogenesis, and how perturbation of these pathways leads to microphthalmia. However, differences exist between species, hence cellular models, such as patient-derived induced pluripotent stem cell (iPSC) optic vesicles, are now being used to provide greater insights into the human disease process. Progress in 3D cellular modelling techniques has enhanced the ability of researchers to study interactions of different cell types during eye development. Through improved molecular knowledge of microphthalmia, preventative or postnatal therapies may be developed, together with establishing genotype-phenotype correlations in order to provide patients with the appropriate prognosis, multidisciplinary care and informed genetic counselling. This review summarises some key discoveries from animal and cellular models of microphthalmia and discusses how innovative new models can be used to further our understanding in the future. Plain language summary Animal and Cellular Models of the Eye Disorder, Microphthalmia (Small Eye) Microphthalmia, meaning a small, underdeveloped eye, is a rare disorder that children are born with. Genetic changes or variations in the environment during the first 3 months of pregnancy can disrupt early development of the eye, resulting in microphthalmia. Up to 11% of blind children have microphthalmia, yet currently no treatments are available. By understanding the genes necessary for eye development, we can determine how disruption by genetic changes or environmental factors can cause this condition. This helps us understand why microphthalmia occurs, and ensure patients are provided with the appropriate clinical care and genetic counselling advice. Additionally, by understanding the causes of microphthalmia, researchers can develop treatments to prevent or reduce the severity of this condition. Animal models, particularly mice, zebrafish and frogs, which can also develop small eyes due to the same genetic/environmental changes, have helped us understand the genes which are important for eye development and can cause birth eye defects when disrupted. Studying a patient's own cells grown in the laboratory can further help researchers understand how changes in genes affect their function. Both animal and cellular models can be used to develop and test new drugs, which could provide treatment options for patients living with microphthalmia. This review summarises the key discoveries from animal and cellular models of microphthalmia and discusses how innovative new models can be used to further our understanding in the future.
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Affiliation(s)
| | | | - Mariya Moosajee
- UCL Institute of Ophthalmology, 11-43 Bath
Street, London, EC1V 9EL, UK
- Moorfields Eye Hospital NHS Foundation Trust,
London, UK
- Great Ormond Street Hospital for Children NHS
Foundation Trust, London, UK
- The Francis Crick Institute, London, UK
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Öztürk Z, O’Kane CJ, Pérez-Moreno JJ. Axonal Endoplasmic Reticulum Dynamics and Its Roles in Neurodegeneration. Front Neurosci 2020; 14:48. [PMID: 32116502 PMCID: PMC7025499 DOI: 10.3389/fnins.2020.00048] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 01/13/2020] [Indexed: 12/13/2022] Open
Abstract
The physical continuity of axons over long cellular distances poses challenges for their maintenance. One organelle that faces this challenge is endoplasmic reticulum (ER); unlike other intracellular organelles, this forms a physically continuous network throughout the cell, with a single membrane and a single lumen. In axons, ER is mainly smooth, forming a tubular network with occasional sheets or cisternae and low amounts of rough ER. It has many potential roles: lipid biosynthesis, glucose homeostasis, a Ca2+ store, protein export, and contacting and regulating other organelles. This tubular network structure is determined by ER-shaping proteins, mutations in some of which are causative for neurodegenerative disorders such as hereditary spastic paraplegia (HSP). While axonal ER shares many features with the tubular ER network in other contexts, these features must be adapted to the long and narrow dimensions of axons. ER appears to be physically continuous throughout axons, over distances that are enormous on a subcellular scale. It is therefore a potential channel for long-distance or regional communication within neurons, independent of action potentials or physical transport of cargos, but involving its physiological roles such as Ca2+ or organelle homeostasis. Despite its apparent stability, axonal ER is highly dynamic, showing features like anterograde and retrograde transport, potentially reflecting continuous fusion and breakage of the network. Here we discuss the transport processes that must contribute to this dynamic behavior of ER. We also discuss the model that these processes underpin a homeostatic process that ensures both enough ER to maintain continuity of the network and repair breaks in it, but not too much ER that might disrupt local cellular physiology. Finally, we discuss how failure of ER organization in axons could lead to axon degenerative diseases, and how a requirement for ER continuity could make distal axons most susceptible to degeneration in conditions that disrupt ER continuity.
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Affiliation(s)
| | - Cahir J. O’Kane
- Department of Genetics, University of Cambridge, Cambridge, United Kingdom
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Nian FS, Li LL, Cheng CY, Wu PC, Lin YT, Tang CY, Ren BS, Tai CY, Fann MJ, Kao LS, Hong CJ, Tsai JW. Rab18 Collaborates with Rab7 to Modulate Lysosomal and Autophagy Activities in the Nervous System: an Overlapping Mechanism for Warburg Micro Syndrome and Charcot-Marie-Tooth Neuropathy Type 2B. Mol Neurobiol 2019; 56:6095-6105. [PMID: 30721447 DOI: 10.1007/s12035-019-1471-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 01/10/2019] [Indexed: 01/24/2023]
Abstract
Mutations in RAB18, a member of small G protein, cause Warburg micro syndrome (WARBM), whose clinical features include vision impairment, postnatal microcephaly, and lower limb spasticity. Previously, our Rab18-/- mice exhibited hind limb weakness and spasticity as well as signs of axonal degeneration in the spinal cord and lumbar spinal nerves. However, the cellular and molecular function of RAB18 and its roles in the pathogenesis of WARBM are still not fully understood. Using immunofluorescence staining and expression of Rab18 and organelle markers, we find that Rab18 associates with lysosomes and actively traffics along neurites in cultured neurons. Interestingly, Rab18-/- neurons exhibit impaired lysosomal transport. Using autophagosome marker LC3-II, we show that Rab18 dysfunction leads to aberrant autophagy activities in neurons. Electron microscopy further reveals accumulation of lipofuscin-like granules in the dorsal root ganglion of Rab18-/- mice. Surprisingly, Rab18 colocalizes, cofractionates, and coprecipitates with the lysosomal regulator Rab7, mutations of which cause Charcot-Marie-Tooth (CMT) neuropathy type 2B. Moreover, Rab7 is upregulated in Rab18-deficient neurons, suggesting a compensatory effect. Together, our results suggest that the functions of RAB18 and RAB7 in lysosomal and autophagic activities may constitute an overlapping mechanism underlying WARBM and CMT pathogenesis in the nervous system.
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Affiliation(s)
- Fang-Shin Nian
- Institute of Brain Science, National Yang-Ming University, Taipei, Taiwan.,Program in Molecular Medicine, National Yang-Ming University and Academia Sinica, Taipei, Taiwan
| | - Lei-Li Li
- Institute of Brain Science, National Yang-Ming University, Taipei, Taiwan
| | - Chih-Ya Cheng
- Department of Pediatrics, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Pei-Chun Wu
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan.,Brain Research Center, National Yang-Ming University, Taipei, Taiwan
| | - You-Tai Lin
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan
| | - Cheng-Yung Tang
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan
| | - Bo-Shiun Ren
- Institute of Brain Science, National Yang-Ming University, Taipei, Taiwan
| | - Chin-Yin Tai
- Institute of Molecular Biology, Academia Sinica, Nankang, Taipei, Taiwan
| | - Ming-Ji Fann
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan.,Brain Research Center, National Yang-Ming University, Taipei, Taiwan
| | - Lung-Sen Kao
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan.,Brain Research Center, National Yang-Ming University, Taipei, Taiwan
| | - Chen-Jee Hong
- Brain Research Center, National Yang-Ming University, Taipei, Taiwan.,Division of Psychiatry, School of Medicine, National Yang-Ming University, Taipei, Taiwan.,Department of Psychiatry, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Jin-Wu Tsai
- Institute of Brain Science, National Yang-Ming University, Taipei, Taiwan. .,Brain Research Center, National Yang-Ming University, Taipei, Taiwan. .,Biopotonics and Molecular Imaging Research Center, National Yang-Ming University, Taipei, Taiwan.
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Rha J, Jones SK, Fidler J, Banerjee A, Leung SW, Morris KJ, Wong JC, Inglis GAS, Shapiro L, Deng Q, Cutler AA, Hanif AM, Pardue MT, Schaffer A, Seyfried NT, Moberg KH, Bassell GJ, Escayg A, García PS, Corbett AH. The RNA-binding protein, ZC3H14, is required for proper poly(A) tail length control, expression of synaptic proteins, and brain function in mice. Hum Mol Genet 2018; 26:3663-3681. [PMID: 28666327 DOI: 10.1093/hmg/ddx248] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Accepted: 06/20/2017] [Indexed: 12/30/2022] Open
Abstract
A number of mutations in genes that encode ubiquitously expressed RNA-binding proteins cause tissue specific disease. Many of these diseases are neurological in nature revealing critical roles for this class of proteins in the brain. We recently identified mutations in a gene that encodes a ubiquitously expressed polyadenosine RNA-binding protein, ZC3H14 (Zinc finger CysCysCysHis domain-containing protein 14), that cause a nonsyndromic, autosomal recessive form of intellectual disability. This finding reveals the molecular basis for disease and provides evidence that ZC3H14 is essential for proper brain function. To investigate the role of ZC3H14 in the mammalian brain, we generated a mouse in which the first common exon of the ZC3H14 gene, exon 13 is removed (Zc3h14Δex13/Δex13) leading to a truncated ZC3H14 protein. We report here that, as in the patients, Zc3h14 is not essential in mice. Utilizing these Zc3h14Δex13/Δex13mice, we provide the first in vivo functional characterization of ZC3H14 as a regulator of RNA poly(A) tail length. The Zc3h14Δex13/Δex13 mice show enlarged lateral ventricles in the brain as well as impaired working memory. Proteomic analysis comparing the hippocampi of Zc3h14+/+ and Zc3h14Δex13/Δex13 mice reveals dysregulation of several pathways that are important for proper brain function and thus sheds light onto which pathways are most affected by the loss of ZC3H14. Among the proteins increased in the hippocampi of Zc3h14Δex13/Δex13 mice compared to control are key synaptic proteins including CaMK2a. This newly generated mouse serves as a tool to study the function of ZC3H14 in vivo.
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Affiliation(s)
- Jennifer Rha
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA.,Graduate Program in Biochemistry, Cell, and Developmental Biology, Emory University, Atlanta, GA 30322, USA
| | - Stephanie K Jones
- Department of Biology.,Graduate Program in Genetics and Molecular Biology, Emory University, Atlanta, GA 30322, USA
| | - Jonathan Fidler
- Department of Anesthesiology, Emory University School of Medicine & Research Division, Atlanta VA Medical Center, Atlanta, GA 30322, USA
| | | | | | - Kevin J Morris
- Graduate Program in Biochemistry, Cell, and Developmental Biology, Emory University, Atlanta, GA 30322, USA.,Department of Biology
| | - Jennifer C Wong
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - George Andrew S Inglis
- Graduate Program in Genetics and Molecular Biology, Emory University, Atlanta, GA 30322, USA.,Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Lindsey Shapiro
- Graduate Program in Genetics and Molecular Biology, Emory University, Atlanta, GA 30322, USA.,Graduate Program in Neuroscience, Emory University, Atlanta, GA 30322, USA
| | - Qiudong Deng
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Alicia A Cutler
- Graduate Program in Biochemistry, Cell, and Developmental Biology, Emory University, Atlanta, GA 30322, USA.,Department of Pharmacology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Adam M Hanif
- Department of Opthamology, Emory University School of Medicine & Research Division, & Atlanta VA Medical Center, Atlanta, GA 30322, USA
| | - Machelle T Pardue
- Department of Opthamology, Emory University School of Medicine & Research Division, & Atlanta VA Medical Center, Atlanta, GA 30322, USA
| | - Ashleigh Schaffer
- Department of Genetics and Genome Sciences, School of Medicine, Case Western Reserve University, Cleveland, OH 44106-4955, USA
| | - Nicholas T Seyfried
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Kenneth H Moberg
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Gary J Bassell
- Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Andrew Escayg
- Graduate Program in Genetics and Molecular Biology, Emory University, Atlanta, GA 30322, USA
| | - Paul S García
- Department of Anesthesiology, Emory University School of Medicine & Research Division, Atlanta VA Medical Center, Atlanta, GA 30322, USA
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Golgi trafficking defects in postnatal microcephaly: The evidence for “Golgipathies”. Prog Neurobiol 2017; 153:46-63. [DOI: 10.1016/j.pneurobio.2017.03.007] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 02/22/2017] [Accepted: 03/29/2017] [Indexed: 12/17/2022]
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8
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Wu Q, Sun X, Yue W, Lu T, Ruan Y, Chen T, Zhang D. RAB18, a protein associated with Warburg Micro syndrome, controls neuronal migration in the developing cerebral cortex. Mol Brain 2016; 9:19. [PMID: 26879639 PMCID: PMC4754921 DOI: 10.1186/s13041-016-0198-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 02/08/2016] [Indexed: 01/23/2023] Open
Abstract
Background Loss of function mutations in RAB18, has been identified in patients with the human neurological and developmental disorder Warburg Micro syndrome. However, the function of RAB18 in brain remains unknown. Results In this study, we report that RAB18 is a critical regulator of neuronal migration and morphogenesis. Using in utero electroporation suppression of RAB18 in the mouse brain impairs radial migration. Overexpression of dominant negative RAB18 or disruption of RAB3GAP (RAB18GEF) also results in delayed neuronal migration in the developing mouse cortex and inhibition of neurite growth in vitro. Moreover, loss of RAB18 induces an acceleration of N-cadherin degradation by lysosomal pathway resulting in the decrease of surface level of N-cadherin on neurons. Conclusions RAB18 regulates neuronal migration and morphogenesis during development. Our findings highlight the critical role of RAB3GAP-RAB18 pathway in the developing cerebral cortex and might explain some of clinical features observed in patients with Warburg Micro syndrome. Electronic supplementary material The online version of this article (doi:10.1186/s13041-016-0198-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Qinwei Wu
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China. .,Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, 100871, China. .,Peking University Sixth Hospital/Institute of Mental Health, Beijing, 100191, China.
| | - Xiaqin Sun
- Peking University Sixth Hospital/Institute of Mental Health, Beijing, 100191, China. .,National Clinical Research Center for Mental Disorders/Key Laboratory for Mental Health, Ministry of Health (Peking University), Beijing, 100191, China.
| | - Weihua Yue
- Peking University Sixth Hospital/Institute of Mental Health, Beijing, 100191, China. .,National Clinical Research Center for Mental Disorders/Key Laboratory for Mental Health, Ministry of Health (Peking University), Beijing, 100191, China.
| | - Tianlan Lu
- Peking University Sixth Hospital/Institute of Mental Health, Beijing, 100191, China. .,National Clinical Research Center for Mental Disorders/Key Laboratory for Mental Health, Ministry of Health (Peking University), Beijing, 100191, China.
| | - Yanyan Ruan
- Peking University Sixth Hospital/Institute of Mental Health, Beijing, 100191, China. .,National Clinical Research Center for Mental Disorders/Key Laboratory for Mental Health, Ministry of Health (Peking University), Beijing, 100191, China.
| | - Tianda Chen
- Peking University Sixth Hospital/Institute of Mental Health, Beijing, 100191, China. .,National Clinical Research Center for Mental Disorders/Key Laboratory for Mental Health, Ministry of Health (Peking University), Beijing, 100191, China.
| | - Dai Zhang
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China. .,Peking University Sixth Hospital/Institute of Mental Health, Beijing, 100191, China. .,National Clinical Research Center for Mental Disorders/Key Laboratory for Mental Health, Ministry of Health (Peking University), Beijing, 100191, China. .,PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China.
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