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Ma T, Wang Y, Yu L, Liu J, Wang T, Sun P, Feng Y, Zhang D, Shi L, He K, Zhao L, Xu Z. Mea6/cTAGE5 cooperates with TRAPPC12 to regulate PTN secretion and white matter development. iScience 2024; 27:109180. [PMID: 38439956 PMCID: PMC10909747 DOI: 10.1016/j.isci.2024.109180] [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: 07/31/2023] [Revised: 11/11/2023] [Accepted: 02/06/2024] [Indexed: 03/06/2024] Open
Abstract
Mutations of TRAPPC12 are associated with progressive childhood encephalopathy including abnormal white matter. However, the underlying pathogenesis is still unclear. Here, we found that Trappc12 deficiency in CG4 and oligodendrocyte progenitor cells (OPCs) affects their differentiation and maturation. In addition, TRAPPC12 interacts with Mea6/cTAGE5, and Mea6/cTAGE5 ablation in OPCs affects their proliferation and differentiation, leading to marked hypomyelination, compromised synaptic functionality, and aberrant behaviors in mice. We reveal that TRAPPC12 is associated with COPII components at ER exit site, and Mea6/cTAGE5 cKO disrupts the trafficking pathway by affecting the distribution and/or expression of TRAPPC12, SEC13, SEC31A, and SAR1. Moreover, we observed marked disturbances in the secretion of pleiotrophin (PTN) in Mea6-deficient OPCs. Notably, exogenous PTN supplementation ameliorated the differentiation deficits of these OPCs. Collectively, our findings indicate that the association between TRAPPC12 and MEA6 is important for cargo trafficking and white matter development.
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Affiliation(s)
- Tiantian Ma
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100083, China
| | - Yaqing Wang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100083, China
| | - Laikang Yu
- Key Laboratory of Physical Fitness and Exercise, Ministry of Education, Beijing Sport University, Beijing, Haidian District, China
| | - Jinghua Liu
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100083, China
| | - Tao Wang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Pengyu Sun
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100083, China
| | - Yinghang Feng
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100083, China
| | - Dan Zhang
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100083, China
| | - Lei Shi
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Kangmin He
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100083, China
| | - Li Zhao
- Key Laboratory of Physical Fitness and Exercise, Ministry of Education, Beijing Sport University, Beijing, Haidian District, China
| | - Zhiheng Xu
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
- University of Chinese Academy of Sciences, Beijing 100083, China
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2
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Almousa H, Lewis SA, Bakhtiari S, Nordlie SH, Pagnozzi A, Magee H, Efthymiou S, Heim JA, Cornejo P, Zaki MS, Anwar N, Maqbool S, Rahman F, Neilson DE, Vemuri A, Jin SC, Yang XR, Heidari A, van Gassen K, Trimouille A, Thauvin-Robinet C, Liu J, Bruel AL, Tomoum H, Shata MO, Hashem MO, Toosi MB, Karimiani EG, Yeşil G, Lingappa L, Baruah D, Ebrahimzadeh F, Van-Gils J, Faivre L, Zamani M, Galehdari H, Sadeghian S, Shariati G, Mohammad R, van der Smagt J, Qari A, Vincent JB, Innes AM, Dursun A, Özgül RK, Akar HT, Bilguvar K, Mignot C, Keren B, Raveli C, Burglen L, Afenjar A, Kaat LD, van Slegtenhorst M, Alkuraya F, Houlden H, Padilla-Lopez S, Maroofian R, Sacher M, Kruer MC. TRAPPC6B biallelic variants cause a neurodevelopmental disorder with TRAPP II and trafficking disruptions. Brain 2024; 147:311-324. [PMID: 37713627 PMCID: PMC10766242 DOI: 10.1093/brain/awad301] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 07/11/2023] [Accepted: 08/10/2023] [Indexed: 09/17/2023] Open
Abstract
Highly conserved transport protein particle (TRAPP) complexes regulate subcellular trafficking pathways. Accurate protein trafficking has been increasingly recognized to be critically important for normal development, particularly in the nervous system. Variants in most TRAPP complex subunits have been found to lead to neurodevelopmental disorders with diverse but overlapping phenotypes. We expand on limited prior reports on TRAPPC6B with detailed clinical and neuroradiologic assessments, and studies on mechanisms of disease, and new types of variants. We describe 29 additional patients from 18 independent families with biallelic variants in TRAPPC6B. We identified seven homozygous nonsense (n = 12 patients) and eight canonical splice-site variants (n = 17 patients). In addition, we identified one patient with compound heterozygous splice-site/missense variants with a milder phenotype and one patient with homozygous missense variants. Patients displayed non-progressive microcephaly, global developmental delay/intellectual disability, epilepsy and absent expressive language. Movement disorders including stereotypies, spasticity and dystonia were also observed. Brain imaging revealed reductions in cortex, cerebellum and corpus callosum size with frequent white matter hyperintensity. Volumetric measurements indicated globally diminished volume rather than specific regional losses. We identified a reduced rate of trafficking into the Golgi apparatus and Golgi fragmentation in patient-derived fibroblasts that was rescued by wild-type TRAPPC6B. Molecular studies revealed a weakened interaction between mutant TRAPPC6B (c.454C>T, p.Q152*) and its TRAPP binding partner TRAPPC3. Patient-derived fibroblasts from the TRAPPC6B (c.454C>T, p.Q152*) variant displayed reduced levels of TRAPPC6B as well as other TRAPP II complex-specific members (TRAPPC9 and TRAPPC10). Interestingly, the levels of the TRAPPC6B homologue TRAPPC6A were found to be elevated. Moreover, co-immunoprecipitation experiments showed that TRAPPC6A co-precipitates equally with TRAPP II and TRAPP III, while TRAPPC6B co-precipitates significantly more with TRAPP II, suggesting enrichment of the protein in the TRAPP II complex. This implies that variants in TRAPPC6B may preferentially affect TRAPP II functions compared to TRAPP III functions. Finally, we assessed phenotypes in a Drosophila TRAPPC6B-deficiency model. Neuronal TRAPPC6B knockdown impaired locomotion and led to wing posture defects, supporting a role for TRAPPC6B in neuromotor function. Our findings confirm the association of damaging biallelic TRAPPC6B variants with microcephaly, intellectual disability, language impairments, and epilepsy. A subset of patients also exhibited dystonia and/or spasticity with impaired ambulation. These features overlap with disorders arising from pathogenic variants in other TRAPP subunits, particularly components of the TRAPP II complex. These findings suggest that TRAPPC6B is essential for brain development and function, and TRAPP II complex activity may be particularly relevant for mediating this function.
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Affiliation(s)
- Hashem Almousa
- Department of Biology, Concordia University, Montreal, Quebec H4B1R6, Canada
| | - Sara A Lewis
- Barrow Neurological Institute, Phoenix Children’s Hospital, Phoenix, AZ 85016, USA
- Departments of Child Health, Cellular and Molecular Medicine, Genetics, and Neurology, University of Arizona College of Medicine—Phoenix, Phoenix, AZ 85004, USA
| | - Somayeh Bakhtiari
- Barrow Neurological Institute, Phoenix Children’s Hospital, Phoenix, AZ 85016, USA
- Departments of Child Health, Cellular and Molecular Medicine, Genetics, and Neurology, University of Arizona College of Medicine—Phoenix, Phoenix, AZ 85004, USA
| | - Sandra Hinz Nordlie
- Barrow Neurological Institute, Phoenix Children’s Hospital, Phoenix, AZ 85016, USA
- Departments of Child Health, Cellular and Molecular Medicine, Genetics, and Neurology, University of Arizona College of Medicine—Phoenix, Phoenix, AZ 85004, USA
| | - Alex Pagnozzi
- CSIRO Health and Biosecurity, The Australian e-Health Research Centre, Brisbane 4029, Australia
| | - Helen Magee
- Barrow Neurological Institute, Phoenix Children’s Hospital, Phoenix, AZ 85016, USA
- Departments of Child Health, Cellular and Molecular Medicine, Genetics, and Neurology, University of Arizona College of Medicine—Phoenix, Phoenix, AZ 85004, USA
| | - Stephanie Efthymiou
- Department of Neuromuscular Disorders, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK
| | - Jennifer A Heim
- Barrow Neurological Institute, Phoenix Children’s Hospital, Phoenix, AZ 85016, USA
| | - Patricia Cornejo
- Pediatric Neuroradiology Division, Pediatric Radiology, Barrow Neurological Institute, Phoenix Children’s Hospital, Phoenix, AZ 85016, USA
- Department of Child Health, University of Arizona College of Medicine, Phoenix, AZ 85004, USA
- Department of Radiology, Mayo Clinic, Scottsdale, AZ 85259, USA
| | - Maha S Zaki
- Clinical Genetics Department, Human Genetics and Genome Research Division, National Research Centre, Cairo 12622, Egypt
- Genetics Department, Armed Forces College of Medicine (AFCM), Cairo 4460015, Egypt
| | - Najwa Anwar
- Department of Developmental-Behavioural Paediatrics, The Children's Hospital and Institute of Child Health, Lahore 54000, Pakistan
| | - Shazia Maqbool
- Department of Developmental-Behavioural Paediatrics, The Children's Hospital and Institute of Child Health, Lahore 54000, Pakistan
| | - Fatima Rahman
- Department of Developmental-Behavioural Paediatrics, The Children's Hospital and Institute of Child Health, Lahore 54000, Pakistan
| | - Derek E Neilson
- Genetics and Metabolism, Phoenix Children’s Hospital, Phoenix, AZ 85016, USA
| | - Anusha Vemuri
- Department of Pathology, University of Chicago, Chicago, IL 60637, USA
| | - Sheng Chih Jin
- Department of Genetics, Washington University, St.Louis, MO 63110, USA
| | - Xiao-Ru Yang
- Department of Medical Genetics and Alberta Children’s Hospital Research Institute, Cumming School of Medicine, University of Calgary, S.W. Calgary, AB T2N 4N1, Canada
| | - Abolfazl Heidari
- Reference Laboratory, Qazvin Medical University, Qazvin 34148-33245, Iran
| | - Koen van Gassen
- Division of Laboratories, Pharmacy and Biomedical Genetics, Section of Clinical Genetics, University Medical Center Utrecht (UMCU), 3584 CX Utrecht, Netherlands
| | - Aurélien Trimouille
- Laboratoire de Génétique Moléculaire, Service de Génétique Médicale, CHU Bordeaux—Hôpital Pellegrin, Place Amélie Raba Léon, 33000 Bordeaux, France
| | - Christel Thauvin-Robinet
- Department of Genetics and Reference Center for Development Disorders and Intellectual Disabilities, FHU TRANSLAD, CHU Dijon Bourgogne, 21000 Dijon, France
- Unité Fontctionnelle d’Innovation diagnostiques des maladies rares, FHU TRANSLAD, CHU Dijon Bourgogne, 21000 Dijon, France
- GAD ‘Génétique des Anomalies du Développement’, INSERM-Université de Bourgogne UMR1231, 21078 Dijon, France
| | - James Liu
- Barrow Neurological Institute, Phoenix Children’s Hospital, Phoenix, AZ 85016, USA
- Departments of Child Health, Cellular and Molecular Medicine, Genetics, and Neurology, University of Arizona College of Medicine—Phoenix, Phoenix, AZ 85004, USA
| | - Ange-Line Bruel
- Unité Fontctionnelle d’Innovation diagnostiques des maladies rares, FHU TRANSLAD, CHU Dijon Bourgogne, 21000 Dijon, France
- GAD ‘Génétique des Anomalies du Développement’, INSERM-Université de Bourgogne UMR1231, 21078 Dijon, France
| | - Hoda Tomoum
- Department of Pediatrics, Ain Shams University, Cairo 11516, Egypt
| | | | - Mais O Hashem
- Department of Translational Genomics, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia
| | - Mehran Beiraghi Toosi
- Pediatric Neurology Department, Ghaem Hospital, Mashhad University of Medical Sciences, Mashhad 13944-91388, Iran
- Neuroscience Research Center, Mashhad University of Medical Science, Mashhad 13944-91388, Iran
| | - Ehsan Ghayoor Karimiani
- Molecular and Clinical Sciences Institute, St.George’s, University of London, London SW17 0RE, UK
| | - Gözde Yeşil
- Istanbul Medical Faculty Department of Medical Genetics, Istanbul University, Istanbul 34452, Turkey
| | - Lokesh Lingappa
- Pediatric Neurology, Rainbow Children Hospital, Hyderabad 500034, India
| | - Debangana Baruah
- Pediatric Neurology, Rainbow Children Hospital, Hyderabad 500034, India
| | - Farnoosh Ebrahimzadeh
- Department of Internal Medicine, Mashhad University of Medical Sciences, Mashhad 13944-91388, Iran
| | - Julien Van-Gils
- Division of Laboratories, Pharmacy and Biomedical Genetics, Section of Clinical Genetics, University Medical Center Utrecht (UMCU), 3584 CX Utrecht, Netherlands
| | - Laurence Faivre
- Department of Genetics and Reference Center for Development Disorders and Intellectual Disabilities, FHU TRANSLAD, CHU Dijon Bourgogne, 21000 Dijon, France
| | - Mina Zamani
- Department of Biology, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz 6135783151, Iran
- Narges Medical Genetics and Prenatal Diagnosis Laboratory, Ahvaz 6155889467, Iran
| | - Hamid Galehdari
- Department of Biology, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz 6135783151, Iran
| | - Saeid Sadeghian
- Department of Pediatric Neurology, Golestan Medical, Educational, and Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz 6135733118, Iran
| | - Gholamreza Shariati
- Narges Medical Genetics and Prenatal Diagnosis Laboratory, Ahvaz 6155889467, Iran
- Department of Medical Genetics, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz 6135733118, Iran
| | - Rahema Mohammad
- Department of Neuromuscular Disorders, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK
| | - Jasper van der Smagt
- Division of Laboratories, Pharmacy and Biomedical Genetics, Section of Clinical Genetics, University Medical Center Utrecht (UMCU), 3584 CX Utrecht, Netherlands
| | - Alya Qari
- Medical Genomics Department, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center, Riyadh 11564, Saudi Arabia
| | - John B Vincent
- Molecular Neuropsychiatry & Development (MiND) Lab, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, Toronto, ON M6J 1H4, Canada
| | - A Micheil Innes
- Department of Medical Genetics and Alberta Children’s Hospital Research Institute, Cumming School of Medicine, University of Calgary, S.W. Calgary, AB T2N 4N1, Canada
| | - Ali Dursun
- Department of Pediatric Metabolism, Hacettepe University, Faculty of Medicine & Institute of Child Health, Ankara 06800, Turkey
| | - R Köksal Özgül
- Department of Pediatric Metabolism, Hacettepe University, Faculty of Medicine & Institute of Child Health, Ankara 06800, Turkey
| | - Halil Tuna Akar
- Department of Pediatric Metabolism, Hacettepe University, Faculty of Medicine & Institute of Child Health, Ankara 06800, Turkey
| | - Kaya Bilguvar
- Department of Medical Genetics, Acibadem Mehmet Ali Aydinlar University, Istanbul 34752, Turkey
- Department of Neurosurgery and Genetics, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Cyril Mignot
- Département de Génétique, APHP Sorbonne Université, Hôpital Trousseau & Groupe Hospitalier Pitié-Salpêtrière, 75013 Paris, France
- Centre de Référence Déficiences Intellectuelles de Causes Rares, 75012 Paris, France
| | - Boris Keren
- Département de Génétique, APHP Sorbonne Université, Hôpital Trousseau & Groupe Hospitalier Pitié-Salpêtrière, 75013 Paris, France
| | - Claudia Raveli
- APHP Sorbonne Université, Service de Neuropédiatrie, Hôpital Trousseau, 75012 Paris, France
| | - Lydie Burglen
- Département de Génétique, Centre de référence des malformations et maladies congénitales du cervelet, APHP. Sorbonne Université, Hôpital Trousseau, 75012 Paris, France
| | - Alexandra Afenjar
- Département de Génétique, Centre de référence des malformations et maladies congénitales du cervelet, APHP. Sorbonne Université, Hôpital Trousseau, 75012 Paris, France
| | - Laura Donker Kaat
- Department of Clinical Genetics, Erasmus Medical Center, 3000 Rotterdam, The Netherlands
| | | | - Fowzan Alkuraya
- Department of Translational Genomics, Center for Genomic Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh 11211, Saudi Arabia
| | - Henry Houlden
- Department of Neuromuscular Disorders, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK
| | - Sergio Padilla-Lopez
- Barrow Neurological Institute, Phoenix Children’s Hospital, Phoenix, AZ 85016, USA
- Departments of Child Health, Cellular and Molecular Medicine, Genetics, and Neurology, University of Arizona College of Medicine—Phoenix, Phoenix, AZ 85004, USA
| | - Reza Maroofian
- Department of Neuromuscular Disorders, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK
| | - Michael Sacher
- Department of Biology, Concordia University, Montreal, Quebec H4B1R6, Canada
- Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec H3A0C7, Canada
| | - Michael C Kruer
- Barrow Neurological Institute, Phoenix Children’s Hospital, Phoenix, AZ 85016, USA
- Departments of Child Health, Cellular and Molecular Medicine, Genetics, and Neurology, University of Arizona College of Medicine—Phoenix, Phoenix, AZ 85004, USA
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Papaioannou P, Wallace MJ, Malhotra N, Mohler PJ, El Refaey M. Biochemical Structure and Function of TRAPP Complexes in the Cardiac System. JACC Basic Transl Sci 2023; 8:1599-1612. [PMID: 38205348 PMCID: PMC10774597 DOI: 10.1016/j.jacbts.2023.03.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 03/14/2023] [Indexed: 01/12/2024]
Abstract
Trafficking protein particle (TRAPP) is well reported to play a role in the trafficking of protein products within the Golgi and endoplasmic reticulum. Dysfunction in TRAPP has been associated with disorders in the nervous and cardiovascular systems, but the majority of literature focuses on TRAPP function in the nervous system solely. Here, we highlight the known pathways of TRAPP and hypothesize potential impacts of TRAPP dysfunction on the cardiovascular system, particularly the role of TRAPP as a guanine-nucleotide exchange factor for Rab1 and Rab11. We also review the various cardiovascular phenotypes associated with changes in TRAPP complexes and their subunits.
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Affiliation(s)
- Peter Papaioannou
- Frick Center for Heart Failure and Arrhythmia Research, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
- Division of Cardiac Surgery, Department of Surgery, College of Medicine, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Michael J. Wallace
- Frick Center for Heart Failure and Arrhythmia Research, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Nipun Malhotra
- Frick Center for Heart Failure and Arrhythmia Research, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
- Division of Cardiac Surgery, Department of Surgery, College of Medicine, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Peter J. Mohler
- Frick Center for Heart Failure and Arrhythmia Research, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
- Department of Physiology and Cell Biology, College of Medicine, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
- Division of Cardiovascular Medicine, Department of Internal Medicine, College of Medicine, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Mona El Refaey
- Frick Center for Heart Failure and Arrhythmia Research, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
- Division of Cardiac Surgery, Department of Surgery, College of Medicine, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
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4
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Polenghi M, Taverna E. Intracellular traffic and polarity in brain development. Front Neurosci 2023; 17:1172016. [PMID: 37859764 PMCID: PMC10583573 DOI: 10.3389/fnins.2023.1172016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 07/31/2023] [Indexed: 10/21/2023] Open
Abstract
Neurons forming the human brain are generated during embryonic development by neural stem and progenitor cells via a process called neurogenesis. A crucial feature contributing to neural stem cell morphological and functional heterogeneity is cell polarity, defined as asymmetric distribution of cellular components. Cell polarity is built and maintained thanks to the interplay between polarity proteins and polarity-generating organelles, such as the endoplasmic reticulum (ER) and the Golgi apparatus (GA). ER and GA affect the distribution of membrane components and work as a hub where glycans are added to nascent proteins and lipids. In the last decades our knowledge on the role of polarity in neural stem and progenitor cells have increased tremendously. However, the role of traffic and associated glycosylation in neural stem and progenitor cells is still relatively underexplored. In this review, we discuss the link between cell polarity, architecture, identity and intracellular traffic, and highlight how studies on neurons have shaped our knowledge and conceptual framework on traffic and polarity. We will then conclude by discussing how a group of rare diseases, called congenital disorders of glycosylation (CDG) offers the unique opportunity to study the contribution of traffic and glycosylation in the context of neurodevelopment.
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5
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Abaji M, Mignon-Ravix C, Gorokhova S, Cacciagli P, Mortreux J, Molinari F, Chabrol B, Sigaudy S, Villard L, Riccardi F. TRAPPC2L-related disorder: first homozygous protein-truncating variant and further delineation of the phenotype. J Med Genet 2023; 60:1021-1025. [PMID: 36849228 DOI: 10.1136/jmg-2022-108677] [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: 09/27/2022] [Accepted: 02/15/2023] [Indexed: 03/01/2023]
Abstract
The TRAPP (TRAfficking Protein Particle) complexes are evolutionarily conserved tethering factors involved in the intracellular transport of vesicles for secretion and autophagy processes. Pathogenic variants in 8 genes (of 14) encoding TRAPP proteins are involved in ultra-rare human diseases, called TRAPPopathies. Seven of them are autosomal recessive neurodevelopmental disorders with overlapping phenotypes. Since 2018, two homozygous missense variants in TRAPPC2L have been reported in five individuals from three unrelated families with early-onset and progressive encephalopathy, with episodic rhabdomyolysis. We now describe the first pathogenic protein-truncating variant in the TRAPPC2L gene found at a homozygous state in two affected siblings. This report provides key genetic evidence invaluable to establishing the gene-disease relationship for this gene and important insights into the TRAPPC2L phenotype. Regression, seizures and postnatal microcephaly initially described are not constant features. Acute episodes of infection do not contribute to the neurological course. HyperCKaemia is part of the clinical picture. Thus, TRAPPC2L syndrome is mainly characterised by a severe neurodevelopmental disorder and a variable degree of muscle involvement, suggesting that it belongs to the clinical entity of rare congenital muscular dystrophies.
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Affiliation(s)
- Mario Abaji
- Génétique Médicale, AP-HM, Marseille, France
- MMG, U1251, Inserm, Aix-Marseille Universite, Marseille, France
| | | | - Svetlana Gorokhova
- Génétique Médicale, AP-HM, Marseille, France
- MMG, U1251, Inserm, Aix-Marseille Universite, Marseille, France
| | - Pierre Cacciagli
- CRB, TAC, Assistance Publique Hopitaux de Marseille, Marseille, France
| | | | | | | | | | - Laurent Villard
- Génétique Médicale, AP-HM, Marseille, France
- MMG, U1251, Inserm, Aix-Marseille Universite, Marseille, France
| | - Florence Riccardi
- MMG, U1251, Inserm, Aix-Marseille Universite, Marseille, France
- Génétique Médicale, Centre Hospitalier Intercommunal Toulon - La Seyne-sur-Mer, Toulon, France
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Chhetri G, Ke Y, Wang P, Usman M, Li Y, Sapp E, Wang J, Ghosh A, Islam MA, Wang X, Boudi A, DiFiglia M, Li X. Impaired XK recycling for importing manganese underlies striatal vulnerability in Huntington's disease. J Cell Biol 2022; 221:213461. [PMID: 36099524 PMCID: PMC9475296 DOI: 10.1083/jcb.202112073] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 06/15/2022] [Accepted: 07/29/2022] [Indexed: 02/08/2023] Open
Abstract
Mutant huntingtin, which causes Huntington's disease (HD), is ubiquitously expressed but induces preferential loss of striatal neurons by unclear mechanisms. Rab11 dysfunction mediates homeostatic disturbance of HD neurons. Here, we report that Rab11 dysfunction also underscores the striatal vulnerability in HD. We profiled the proteome of Rab11-positive endosomes of HD-vulnerable striatal cells to look for protein(s) linking Rab11 dysfunction to striatal vulnerability in HD and found XK, which triggers the selective death of striatal neurons in McLeod syndrome. XK was trafficked together with Rab11 and was diminished on the surface of immortalized HD striatal cells and striatal neurons in HD mouse brains. We found that XK participated in transporting manganese, an essential trace metal depleted in HD brains. Introducing dominantly active Rab11 into HD striatal cells improved XK dynamics and increased manganese accumulation in an XK-dependent manner. Our study suggests that impaired Rab11-based recycling of XK onto cell surfaces for importing manganese is a driver of striatal dysfunction in Huntington's disease.
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Affiliation(s)
- Gaurav Chhetri
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, China
| | - Yuting Ke
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, China.,Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA
| | - Ping Wang
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA.,Department of Neurology, The Second Hospital, Cheeloo College of Medicine, Shandong University, Ji'nan, China
| | - Muhammad Usman
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, China
| | - Yan Li
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, China
| | - Ellen Sapp
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA
| | - Jing Wang
- Instrumental Analysis Center, Shanghai Jiao Tong University, Shanghai, China
| | - Arabinda Ghosh
- Department of Botany, Microbiology Division, Gauhati University, Guwahati, Assam, India
| | - Md Ariful Islam
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, China
| | - Xiaolong Wang
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, China
| | - Adel Boudi
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA
| | - Marian DiFiglia
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA
| | - Xueyi Li
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, China.,Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA
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7
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Rawlins LE, Almousa H, Khan S, Collins SC, Milev MP, Leslie J, Saint-Dic D, Khan V, Hincapie AM, Day JO, McGavin L, Rowley C, Harlalka GV, Vancollie VE, Ahmad W, Lelliott CJ, Gul A, Yalcin B, Crosby AH, Sacher M, Baple EL. Biallelic variants in TRAPPC10 cause a microcephalic TRAPPopathy disorder in humans and mice. PLoS Genet 2022; 18:e1010114. [PMID: 35298461 PMCID: PMC8963566 DOI: 10.1371/journal.pgen.1010114] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Revised: 03/29/2022] [Accepted: 02/20/2022] [Indexed: 11/25/2022] Open
Abstract
The highly evolutionarily conserved transport protein particle (TRAPP) complexes (TRAPP II and III) perform fundamental roles in subcellular trafficking pathways. Here we identified biallelic variants in TRAPPC10, a component of the TRAPP II complex, in individuals with a severe microcephalic neurodevelopmental disorder. Molecular studies revealed a weakened interaction between mutant TRAPPC10 and its putative adaptor protein TRAPPC2L. Studies of patient lymphoblastoid cells revealed an absence of TRAPPC10 alongside a concomitant absence of TRAPPC9, another key TRAPP II complex component associated with a clinically overlapping neurodevelopmental disorder. The TRAPPC9/10 reduction phenotype was recapitulated in TRAPPC10-/- knockout cells, which also displayed a membrane trafficking defect. Notably, both the reduction in TRAPPC9 levels and the trafficking defect in these cells could be rescued by wild type but not mutant TRAPPC10 gene constructs. Moreover, studies of Trappc10-/- knockout mice revealed neuroanatomical brain defects and microcephaly, paralleling findings seen in the human condition as well as in a Trappc9-/- mouse model. Together these studies confirm autosomal recessive TRAPPC10 variants as a cause of human disease and define TRAPP-mediated pathomolecular outcomes of importance to TRAPPC9 and TRAPPC10 mediated neurodevelopmental disorders in humans and mice. Microcephalic neurodevelopmental disorders are a group of conditions that are often inherited in families, involving small head size and abnormal brain development and function. This often results in delayed development of an affected child, affecting their movement, language and/or non-verbal communication and learning, as well as seizures and neuropsychiatric problems. A group of proteins called the transport protein particles (TRAPPs) are important for the transport of cargos inside cells. Alterations within a number of the TRAPP proteins have previously been associated with human inherited diseases called the ‘TRAPPopathies’, which involve neurodevelopmental and skeletal abnormalities. Here we show that TRAPPC10 gene alterations cause a new TRAPPopathy microcephalic neurodevelopmental disorder, and we provide a detailed clinical description of the condition termed ‘TRAPPC10-related disorder’. Our studies in mice lacking the TRAPPC10 gene identified similar features to those of affected humans, including small brain size and skeletal abnormalities. Our molecular studies showed that an affected individual with an alteration in the TRAPPC10 gene has no functional TRAPPC10 protein in their cells, which in turn causes a reduction in levels of another important TRAPP molecule, TRAPPC9. Cells lacking TRAPPC10 also display abnormalities in cellular transport processes. Together our data confirm alterations in TRAPPC10 as a cause of a microcephalic neurodevelopmental disorder in both humans and mice.
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Affiliation(s)
- Lettie E. Rawlins
- RILD Wellcome Wolfson Medical Research Centre, RD&E (Wonford) NHS Foundation Trust, University of Exeter Medical School, Exeter, United Kingdom
- Peninsula Clinical Genetics Service, Royal Devon & Exeter Hospital (Heavitree), Exeter, United Kingdom
| | - Hashem Almousa
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Shazia Khan
- RILD Wellcome Wolfson Medical Research Centre, RD&E (Wonford) NHS Foundation Trust, University of Exeter Medical School, Exeter, United Kingdom
- Department of Biological Sciences, International Islamic University, Islamabad, Pakistan
| | - Stephan C. Collins
- Institute of Genetics and Molecular and Cellular Biology, Inserm, Illkirch, France
- Inserm, University of Bourgogne Franche-Comté, Dijon, France
| | - Miroslav P. Milev
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Joseph Leslie
- RILD Wellcome Wolfson Medical Research Centre, RD&E (Wonford) NHS Foundation Trust, University of Exeter Medical School, Exeter, United Kingdom
| | - Djenann Saint-Dic
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Valeed Khan
- Department of Molecular Diagnostics, Rehman Medical Institute, Peshawar, Pakistan
| | | | - Jacob O. Day
- RILD Wellcome Wolfson Medical Research Centre, RD&E (Wonford) NHS Foundation Trust, University of Exeter Medical School, Exeter, United Kingdom
- Faculty of Health, University of Plymouth, Plymouth, United Kingdom
| | - Lucy McGavin
- University Hospitals Plymouth NHS Trust, Plymouth, United Kingdom
| | | | - Gaurav V. Harlalka
- RILD Wellcome Wolfson Medical Research Centre, RD&E (Wonford) NHS Foundation Trust, University of Exeter Medical School, Exeter, United Kingdom
- Department of Pharmacology, Rajarshi Shahu College of Pharmacy, Malvihir, Buldana, India
| | | | - Wasim Ahmad
- Department of Biochemistry, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | | | - Asma Gul
- Department of Biological Sciences, International Islamic University, Islamabad, Pakistan
| | - Binnaz Yalcin
- Institute of Genetics and Molecular and Cellular Biology, Inserm, Illkirch, France
- Inserm, University of Bourgogne Franche-Comté, Dijon, France
| | - Andrew H. Crosby
- RILD Wellcome Wolfson Medical Research Centre, RD&E (Wonford) NHS Foundation Trust, University of Exeter Medical School, Exeter, United Kingdom
| | - Michael Sacher
- Department of Biology, Concordia University, Montreal, Quebec, Canada
- Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec, Canada
| | - Emma L. Baple
- RILD Wellcome Wolfson Medical Research Centre, RD&E (Wonford) NHS Foundation Trust, University of Exeter Medical School, Exeter, United Kingdom
- Peninsula Clinical Genetics Service, Royal Devon & Exeter Hospital (Heavitree), Exeter, United Kingdom
- * E-mail:
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8
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Kotecha UH, Mistri M, Rayabarapu P, Shah P, Shah N. The diagnostic utility of exome-based carrier screening in families with a positive family history. Am J Med Genet A 2022; 188:1323-1333. [PMID: 34997808 DOI: 10.1002/ajmg.a.62633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 10/15/2021] [Accepted: 12/26/2021] [Indexed: 11/09/2022]
Abstract
Identification of disease-causing variants in families with a history of a suspected recessive disorder is essential for appropriate counseling and reproductive decision making. The present case series depicts the utility of whole exome-based phenotypes-driven carrier analysis in 14 families with a positive family history. A phenotype-based analysis revealed a putative diagnostic yield of 71.4%. Proband sample, though insufficient, was available in only one family, which allowed the diagnosis to be confirmed. In the remaining nine families, despite the detection of heterozygous pathogenic/likely pathogenic variants, only a putative diagnosis was possible due to incomplete proband phenotyping as well as nonavailability of proband samples. We describe the youngest known patient homozygous for a likely pathogenic variant in PPP1R21. He is currently asymptomatic at 7 days of life and has a simplified gyral pattern on neuroimaging. The case series, though small, captures the challenges in the diagnosis of genetic disorders in low to middle income countries with in-equitable health care access. It reinforces the significance of detailed phenotyping in the proband as well as the importance of DNA storage for a conclusive diagnosis. A recurring post-test counseling challenge was risk ascertainment and reproductive decision making in subsequent pregnancies if the detected pathogenic/likely pathogenic variants are co-inherited, in families with a putative diagnosis. When opted for, prenatal testing in such a scenario would be limited in its ability to comment on the fetal status with respect to the disorder in the proband.
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Affiliation(s)
| | - Mehul Mistri
- Neuberg Centre for Genomic Medicine, Ahmedabad, India
| | | | - Parth Shah
- Neuberg Centre for Genomic Medicine, Ahmedabad, India
| | - Nidhi Shah
- Neuberg Centre for Genomic Medicine, Ahmedabad, India
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9
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Zuo MT, Huang SJ, Wu Y, Tang MH, Yu H, Qi XJ, Liu ZY. A proteomics study of the subacute toxicity of rat brain after long-term exposure of Gelsemium elegans. Curr Mol Pharmacol 2021; 15:794-801. [PMID: 34886788 DOI: 10.2174/1874467214666211209144139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 08/25/2021] [Accepted: 10/07/2021] [Indexed: 11/22/2022]
Abstract
BACKGROUND Gelsemium elegans (G. elegans) has been shown to have strong pharmacological and pharmacodynamic effects in relevant studies both in China and USA. G. elegans has been used as a traditional medicine to treat a variety of diseases and even has the potential to be an alternative to laboratory synthesized drugs. However, its toxicity severely limited its application and development. At present, there is little attention paid to protein changes in toxicity. AIM This study investigated the toxicity effects after long-term exposure of G. elegans of the rat brain through proteomic. METHOD 11 differential abundance proteins were detected, among which 8 proteins were higher in the G. elegans- exposure group than in the control group, including Ig-like domain-containing protein (N/A), receptor-type tyrosine-protein phosphatase C (Ptprc), disheveled segment polarity protein 3 (Dvl3), trafficking protein particle complex 12 (Trappc12), seizure-related 6 homolog-like (Sez6l), transmembrane 9 superfamily member 4 (Tm9sf4), DENN domain-containing protein 5A (Dennd5a) and Tle4, whereas the other 3 proteins do the opposite including Golgi to ER traffic protein 4 (Get4), vacuolar protein sorting 4 homolog B (Vps4b) and cadherin-related 23 (CDH23). Furthermore, we performed validation of WB analysis on the key protein CDH23. RESULT Finally, only fewer proteins and related metabolic pathways were affected, indicating that there was no accumulative toxicity of G. elegans. G. elegans has the potential to develop and utilize of its pharmacological activity. CHD23, however, is a protein associated with hearing. CONCLUSION Whether the hearing impairment is a sequela after G. elegans exposure remains to be further studied.
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Affiliation(s)
- Meng-Ting Zuo
- College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, Hunan. China
| | - Si-Juan Huang
- College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, Hunan. China
| | - Yong Wu
- College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, Hunan. China
| | - Mo-Huan Tang
- College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, Hunan. China
| | - Hui Yu
- Hunan Engineering Technology Research Center of Veterinary Drugs, Hunan Agricultural University, Changsha 410128, Hunan. China
| | - Xue-Jia Qi
- College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, Hunan. China
| | - Zhao-Ying Liu
- College of Veterinary Medicine, Hunan Agricultural University, Changsha 410128, Hunan. China
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10
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Munot P, McCrea N, Torelli S, Manzur A, Sewry C, Chambers D, Feng L, Ala P, Zaharieva I, Ragge N, Roper H, Marton T, Cox P, Milev MP, Liang WC, Maruyama S, Nishino I, Sacher M, Phadke R, Muntoni F. TRAPPC11-related muscular dystrophy with hypoglycosylation of alpha-dystroglycan in skeletal muscle and brain. Neuropathol Appl Neurobiol 2021; 48:e12771. [PMID: 34648194 DOI: 10.1111/nan.12771] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Revised: 08/23/2021] [Accepted: 09/12/2021] [Indexed: 11/30/2022]
Abstract
AIMS TRAPPC11, a subunit of the transport protein particle (TRAPP) complex, is important for complex integrity and anterograde membrane transport from the endoplasmic reticulum (ER) to the ER-Golgi intermediate compartment. Several individuals with TRAPPC11 mutations have been reported with muscle weakness and other features including brain, liver, skeletal and eye involvement. A detailed analysis of brain and muscle pathology will further our understanding of the presentation and aetiology of TRAPPC11 disease. METHODS We describe five cases of early-onset TRAPPC11-related muscular dystrophy with a systematic review of muscle pathology in all five individuals, post-mortem brain pathology findings in one and membrane trafficking assays in another. RESULTS All affected individuals presented in infancy with muscle weakness, motor delay and elevated serum creatine kinase (CK). Additional features included cataracts, liver disease, intellectual disability, cardiomyopathy, movement disorder and structural brain abnormalities. Muscle pathology in all five revealed dystrophic changes, universal hypoglycosylation of alpha-dystroglycan and variably reduced dystrophin-associated complex proteins. Membrane trafficking assays showed defective Golgi trafficking in one individual. Neuropathological examination of one individual revealed cerebellar atrophy, granule cell hypoplasia, Purkinje cell (PC) loss, degeneration and dendrite dystrophy, reduced alpha-dystroglycan (IIH6) expression in PC and dentate neurones and absence of neuronal migration defects. CONCLUSIONS This report suggests that recessive mutations in TRAPPC11 are linked to muscular dystrophies with hypoglycosylation of alpha-dystroglycan. The structural cerebellar involvement that we document for the first time resembles the neuropathology reported in N-linked congenital disorders of glycosylation (CDG) such as PMM2-CDG, suggesting defects in multiple glycosylation pathways in this condition.
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Affiliation(s)
- Pinki Munot
- Dubowitz Neuromuscular Centre, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Nadine McCrea
- Dubowitz Neuromuscular Centre, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Silvia Torelli
- UCL, Dubowitz Neuromuscular Centre, Great Ormond Street Institute of Child Health, London, UK
| | - Adnan Manzur
- Dubowitz Neuromuscular Centre, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Caroline Sewry
- Dubowitz Neuromuscular Centre, Division of Neuropathology, UCL Institute of Neurology, London, UK
| | - Darren Chambers
- Dubowitz Neuromuscular Centre, Division of Neuropathology, UCL Institute of Neurology, London, UK
| | - Lucy Feng
- Dubowitz Neuromuscular Centre, Division of Neuropathology, UCL Institute of Neurology, London, UK
| | - Pierpaolo Ala
- UCL, Dubowitz Neuromuscular Centre, Great Ormond Street Institute of Child Health, London, UK
| | - Irina Zaharieva
- UCL, Dubowitz Neuromuscular Centre, Great Ormond Street Institute of Child Health, London, UK
| | - Nicola Ragge
- Birmingham Women's and Children's NHS Foundation Hospital Trust, West Midlands Regional Clinical Genetics Service and Birmingham Health Partners, Birmingham, UK
| | - Helen Roper
- Department of Paediatrics, Birmingham Heartlands Hospital, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - Tamas Marton
- Department of Histopathology, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK
| | - Phil Cox
- Department of Histopathology, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK
| | - Miroslav P Milev
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Wen-Chen Liang
- Department of Pediatrics, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Shinsuke Maruyama
- Department of Paediatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Ichizo Nishino
- Department of Neuromuscular Research, National Institute of Neuroscience, National Centre of Neurology and Psychiatry, Kodaira, Japan
| | - Michael Sacher
- Department of Biology, Concordia University, Montreal, Quebec, Canada.,Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec, Canada
| | - Rahul Phadke
- Dubowitz Neuromuscular Centre, Division of Neuropathology, UCL Institute of Neurology, London, UK.,Division of Neuropathology, University College London Hospitals NHS Foundation Trust National Hospital for Neurology and Neurosurgery, London, UK
| | - Francesco Muntoni
- Dubowitz Neuromuscular Centre, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK.,UCL Great Ormond Street Institute of Child Health, NIHR Great Ormond Street Hospital Biomedical Research Centre, London, UK
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11
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Yang Y, Liu W, Jin Y, Chen M, Lu J, Yu Y, Ren H, Han S, Chu P, Guo Y, Zhang J, Ni X. Identification of potential pathogenic mutations in Chinese children with first branchial cleft anomalies detected by whole-exome sequencing. Pediatr Investig 2021; 5:211-216. [PMID: 34589676 PMCID: PMC8458719 DOI: 10.1002/ped4.12263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 12/08/2020] [Indexed: 11/30/2022] Open
Abstract
IMPORTANCE First branchial cleft anomalies (FBCAs) are rare congenital malformations, accounting for < 8% of all branchial cleft anomalies. However, little is currently known about the cause of FBCAs at the molecular level. OBJECTIVE To identify genomic alterations related to the genetic etiology of FBCAs in Chinese children. METHODS We performed whole-exome sequencing of samples from 10 pediatric patients with FBCAs. Data analysis was carried out using the Burrow-Wheeler Alignment software package, and the dbSNP database for comparisons. Rare variants were further validated by Sanger sequencing. Insertion/deletions (indels) were examined using the Genome Analysis Toolkit. RESULTS We identified 14 non-synonymous mutations in seven potential FBCA-susceptibility genes (TRAPPC12, NRP2, NPNT, SH3RF2, RHPN1, TENM4, and ARMCX4). We also detected 133 shared small indels in 125 genes. Gene Ontology analysis indicated that most of the identified genes played critical roles in development and differentiation pathways involved in regulating organ development. INTERPRETATION We characterized the mutational landscape in pathways involved in development and differentiation in Chinese children with FBCA. The results identified potential pathogenic genes and mutations related to FBCA, and provide molecular-level support for the branchial theory of FBCA pathogenesis.
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Affiliation(s)
- Yeran Yang
- Beijing Key Laboratory for Pediatric Diseases of OtolaryngologyHead and Neck SurgeryMOE Key Laboratory of Major Diseases in ChildrenBeijing Pediatric Research InstituteBeijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina
- Beijing Advanced Innovation Center for Big Data‐Based Precision MedicineBeihang University & Capital Medical UniversityBeijingChina
| | - Wei Liu
- Department of Otolaryngology, Head and Neck SurgeryBeijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina
| | - Yaqiong Jin
- Beijing Key Laboratory for Pediatric Diseases of OtolaryngologyHead and Neck SurgeryMOE Key Laboratory of Major Diseases in ChildrenBeijing Pediatric Research InstituteBeijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina
- Beijing Advanced Innovation Center for Big Data‐Based Precision MedicineBeihang University & Capital Medical UniversityBeijingChina
| | - Min Chen
- Beijing Key Laboratory for Pediatric Diseases of OtolaryngologyHead and Neck SurgeryMOE Key Laboratory of Major Diseases in ChildrenBeijing Pediatric Research InstituteBeijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina
- Beijing Advanced Innovation Center for Big Data‐Based Precision MedicineBeihang University & Capital Medical UniversityBeijingChina
| | - Jie Lu
- Beijing Key Laboratory for Pediatric Diseases of OtolaryngologyHead and Neck SurgeryMOE Key Laboratory of Major Diseases in ChildrenBeijing Pediatric Research InstituteBeijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina
- Beijing Advanced Innovation Center for Big Data‐Based Precision MedicineBeihang University & Capital Medical UniversityBeijingChina
| | - Yongbo Yu
- Beijing Key Laboratory for Pediatric Diseases of OtolaryngologyHead and Neck SurgeryMOE Key Laboratory of Major Diseases in ChildrenBeijing Pediatric Research InstituteBeijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina
- Beijing Advanced Innovation Center for Big Data‐Based Precision MedicineBeihang University & Capital Medical UniversityBeijingChina
| | - Huimin Ren
- Beijing Key Laboratory for Pediatric Diseases of OtolaryngologyHead and Neck SurgeryMOE Key Laboratory of Major Diseases in ChildrenBeijing Pediatric Research InstituteBeijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina
- Beijing Advanced Innovation Center for Big Data‐Based Precision MedicineBeihang University & Capital Medical UniversityBeijingChina
| | - Shujing Han
- Beijing Key Laboratory for Pediatric Diseases of OtolaryngologyHead and Neck SurgeryMOE Key Laboratory of Major Diseases in ChildrenBeijing Pediatric Research InstituteBeijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina
- Beijing Advanced Innovation Center for Big Data‐Based Precision MedicineBeihang University & Capital Medical UniversityBeijingChina
| | - Ping Chu
- Beijing Key Laboratory for Pediatric Diseases of OtolaryngologyHead and Neck SurgeryMOE Key Laboratory of Major Diseases in ChildrenBeijing Pediatric Research InstituteBeijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina
- Beijing Advanced Innovation Center for Big Data‐Based Precision MedicineBeihang University & Capital Medical UniversityBeijingChina
| | - Yongli Guo
- Beijing Key Laboratory for Pediatric Diseases of OtolaryngologyHead and Neck SurgeryMOE Key Laboratory of Major Diseases in ChildrenBeijing Pediatric Research InstituteBeijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina
- Beijing Advanced Innovation Center for Big Data‐Based Precision MedicineBeihang University & Capital Medical UniversityBeijingChina
| | - Jie Zhang
- Department of Otolaryngology, Head and Neck SurgeryBeijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina
| | - Xin Ni
- Beijing Key Laboratory for Pediatric Diseases of OtolaryngologyHead and Neck SurgeryMOE Key Laboratory of Major Diseases in ChildrenBeijing Pediatric Research InstituteBeijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina
- Beijing Advanced Innovation Center for Big Data‐Based Precision MedicineBeihang University & Capital Medical UniversityBeijingChina
- Department of Otolaryngology, Head and Neck SurgeryBeijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina
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12
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Tang BL. Defects in early secretory pathway transport machinery components and neurodevelopmental disorders. Rev Neurosci 2021; 32:851-869. [PMID: 33781010 DOI: 10.1515/revneuro-2021-0020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 03/12/2021] [Indexed: 12/23/2022]
Abstract
The early secretory pathway, provisionally comprising of vesicular traffic between the endoplasmic reticulum (ER) and the Golgi apparatus, occurs constitutively in mammalian cells. Critical for a constant supply of secretory and plasma membrane (PM) materials, the pathway is presumably essential for general cellular function and survival. Neurons exhibit a high intensity in membrane dynamics and protein/lipid trafficking, with differential and polarized trafficking towards the somatodendritic and axonal PM domains. Mutations in genes encoding early secretory pathway membrane trafficking machinery components are known to result in neurodevelopmental or neurological disorders with disease manifestation in early life. Here, such rare disorders associated with autosomal recessive mutations in coat proteins, membrane tethering complexes and membrane fusion machineries responsible for trafficking in the early secretory pathway are summarily discussed. These mutations affected genes encoding subunits of coat protein complex I and II, subunits of transport protein particle (TRAPP) complexes, members of the YIP1 domain family (YIPF) and a SNAP receptor (SNARE) family member. Why the ubiquitously present and constitutively acting early secretory pathway machinery components could specifically affect neurodevelopment is addressed, with the plausible underlying disease etiologies and neuropathological mechanisms resulting from these mutations explored.
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Affiliation(s)
- Bor Luen Tang
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 8 Medical Drive, Singapore117597, Singapore
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13
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Milev MP, Saint-Dic D, Zardoui K, Klopstock T, Law C, Distelmaier F, Sacher M. The phenotype associated with variants in TANGO2 may be explained by a dual role of the protein in ER-to-Golgi transport and at the mitochondria. J Inherit Metab Dis 2021; 44:426-437. [PMID: 32909282 DOI: 10.1002/jimd.12312] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Revised: 08/13/2020] [Accepted: 08/31/2020] [Indexed: 12/17/2022]
Abstract
TANGO2 variants result in a complex disease phenotype consisting of recurrent crisis-induced rhabdomyolysis, encephalopathy, seizures, lactic acidosis, hypoglycemia, and cardiac arrhythmias. Although first described in a fruit fly model as a protein necessary for some aspect of Golgi function and organization, its role in the cell at a fundamental level has not been addressed. Such studies are necessary to better counsel families regarding treatment options and nutrition management to mitigate the metabolic aspects of the disease. The few studies performed to address the pathway(s) in which TANGO2 functions have led to enigmatic results, with some suggesting defects in membrane traffic while others suggest unknown mitochondrial defects. Here, we have performed a robust membrane trafficking assay on fibroblasts derived from three different individuals harboring TANGO2 variants and show that there is a significant delay in the movement of cargo between the endoplasmic reticulum and the Golgi. Importantly, this delay was attributed to a defect in TANGO2 function. We further show that a portion of TANGO2 protein localizes to the mitochondria through a necessary but not sufficient stretch of amino acids at the amino terminus of the protein. Fibroblasts from affected individuals also displayed changes in mitochondrial morphology. We conclude that TANGO2 functions in both membrane trafficking and in some as yet undetermined role in mitochondria physiology. The phenotype of affected individuals can be partially explained by this dual involvement of the protein.
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Affiliation(s)
- Miroslav P Milev
- Department of Biology, Concordia University, Montreal Quebec, Canada
| | - Djenann Saint-Dic
- Department of Biology, Concordia University, Montreal Quebec, Canada
| | - Khashayar Zardoui
- Department of Biology, Concordia University, Montreal Quebec, Canada
| | - Thomas Klopstock
- Department of Neurology, Friedrich-Baur-Institute, Ludwig-Maximilians-University, Munich, Germany
- German Center for Neurodegenerative Diseases (DZNE), Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Christopher Law
- Centre for Microscopy and Cellular Imaging, Concordia University, Quebec, Canada
| | - Felix Distelmaier
- Department of General Pediatrics, Neonatology and Pediatric Cardiology, University Children's Hospital Düsseldorf, Medical faculty, Heinrich Heine University, Düsseldorf, Germany
| | - Michael Sacher
- Department of Biology, Concordia University, Montreal Quebec, Canada
- Department of Anatomy and Cell Biology, McGill University, Quebec, Canada
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14
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Jenkins ML, Harris NJ, Dalwadi U, Fleming KD, Ziemianowicz DS, Rafiei A, Martin EM, Schriemer DC, Yip CK, Burke JE. The substrate specificity of the human TRAPPII complex's Rab-guanine nucleotide exchange factor activity. Commun Biol 2020; 3:735. [PMID: 33277614 PMCID: PMC7719173 DOI: 10.1038/s42003-020-01459-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 10/13/2020] [Indexed: 12/15/2022] Open
Abstract
The TRAnsport Protein Particle (TRAPP) complexes act as Guanine nucleotide exchange factors (GEFs) for Rab GTPases, which are master regulators of membrane trafficking in eukaryotic cells. In metazoans, there are two large multi-protein TRAPP complexes: TRAPPII and TRAPPIII, with the TRAPPII complex able to activate both Rab1 and Rab11. Here we present detailed biochemical characterisation of Rab-GEF specificity of the human TRAPPII complex, and molecular insight into Rab binding. GEF assays of the TRAPPII complex against a panel of 20 different Rab GTPases revealed GEF activity on Rab43 and Rab19. Electron microscopy and chemical cross-linking revealed the architecture of mammalian TRAPPII. Hydrogen deuterium exchange MS showed that Rab1, Rab11 and Rab43 share a conserved binding interface. Clinical mutations in Rab11, and phosphomimics of Rab43, showed decreased TRAPPII GEF mediated exchange. Finally, we designed a Rab11 mutation that maintained TRAPPII-mediated GEF activity while decreasing activity of the Rab11-GEF SH3BP5, providing a tool to dissect Rab11 signalling. Overall, our results provide insight into the GTPase specificity of TRAPPII, and how clinical mutations disrupt this regulation. Here the authors reveal unique structural organization of the mammalian TRAPPII complex, which is critical in regulating membrane trafficking. They find that TRAPPII serves as a guanine nucleotide exchange factor for unexpected Rab GTPases such as Rab43 and Rab19.
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Affiliation(s)
- Meredith L Jenkins
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, V8W 2Y2, Canada
| | - Noah J Harris
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, V8W 2Y2, Canada
| | - Udit Dalwadi
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
| | - Kaelin D Fleming
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, V8W 2Y2, Canada
| | - Daniel S Ziemianowicz
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Atefeh Rafiei
- Department of Chemistry, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Emily M Martin
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, V8W 2Y2, Canada
| | - David C Schriemer
- Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, AB, T2N 4N1, Canada.,Department of Chemistry, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Calvin K Yip
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
| | - John E Burke
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, V8W 2Y2, Canada. .,Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, V6T 1Z3, Canada.
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15
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Aslanger AD, Demiral E, Sonmez-Sahin S, Guler S, Goncu B, Yucesan E, Iscan A, Saltik S, Yesil G. Expanding Clinical Phenotype of TRAPPC12-Related Childhood Encephalopathy: Two Cases and Review of Literature. Neuropediatrics 2020; 51:430-434. [PMID: 32369837 DOI: 10.1055/s-0040-1710526] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Biallelic mutations in the TRAPPC12 gene are responsible for early-onset progressive encephalopathy with brain atrophy and spasticity (PEBAS). To date, three different allelic variants have been reported. Next-generation sequencing allowed discovery of unique alternations in this gene with different phenotypes. We report two patients carrying TRAPPC12 variants, one previously reported and one unknown mutation, with severe neurodevelopmental delay and brain atrophy. Standard clinical examination and cranial imaging studies were performed in these two unrelated patients. In addition, whole-exome sequencing was performed, followed by Sanger sequencing for verification. The first patient, a 2-year-old boy, was found to be homozygous for the previously reported c.1880C > T (p.Ala627Val) mutation. He presented with a phenotype including severe progressive cortical atrophy, moderate cerebellar atrophy, epilepsy, and microcephaly, very similar to the previously reported cases. The second case, a 9-year-old boy, carried a novel homozygous c.679T > G (p.Phe227Val) variant and presented with mild cortical atrophy, severe cerebellar atrophy, and neither clinically manifest epilepsy nor microcephaly, which were previously considered typical findings in PEBAS with TRAPPC12 mutations. Our findings suggest that clinical and brain imaging findings might be more variable than previously anticipated; however, a larger number of observations would benefit for broader phenotypic spectrum.
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Affiliation(s)
- Ayca Dilruba Aslanger
- Department of Medical Genetics, Faculty of Medicine, Bezmialem Vakıf University, Istanbul, Turkey
| | - Emine Demiral
- Department of Medical Genetics, Istanbul Training and Research Hospital, Istanbul, Turkey
| | - Seyma Sonmez-Sahin
- Department of Pediatric Neurology, Faculty of Medicine, Bezmialem Vakıf University, Istanbul, Turkey
| | - Serhat Guler
- Department of Pediatric Neurology, Cerrahpasa Faculty of Medicine Hospital, Istanbul University, Istanbul, Turkey
| | - Beyza Goncu
- Experimental Research Center, Bezmialem Vakıf University, Istanbul, Turkey
| | - Emrah Yucesan
- Institute of Life Sciences and Biotechnology, Bezmialem Vakıf University, Istanbul, Turkey
| | - Akın Iscan
- Department of Pediatric Neurology, Faculty of Medicine, Bezmialem Vakıf University, Istanbul, Turkey
| | - Sema Saltik
- Department of Pediatric Neurology, Cerrahpasa Faculty of Medicine Hospital, Istanbul University, Istanbul, Turkey
| | - Gozde Yesil
- Department of Medical Genetics, Faculty of Medicine, Bezmialem Vakıf University, Istanbul, Turkey
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16
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Eldeeb MA, Zorca CE, Ragheb MA, Rashidi FB, Salah El-Din DS. Fine-tuning ER-phagy by post-translational modifications. Bioessays 2020; 43:e2000212. [PMID: 33210303 DOI: 10.1002/bies.202000212] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 10/05/2020] [Accepted: 10/06/2020] [Indexed: 01/23/2023]
Abstract
Autophagy functions in both selective and non-selective ways to maintain cellular homeostasis. Endoplasmic reticulum autophagy (ER-phagy) is a subclass of autophagy responsible for the degradation of the endoplasmic reticulum through selective encapsulation into autophagosomes. ER-phagy occurs both under physiological conditions and in response to stress cues, and plays a crucial role in maintaining the homeostatic control of the organelle. Although specific receptors that target parts of the ER membrane, as well as, internal proteins for lysosomal degradation have been identified, the molecular regulation of ER-phagy has been elusive. Recent work has uncovered novel regulators of ER-phagy that involve post-translational modifications of ER-resident proteins and functional cross-talk with other cellular processes. Herein, we discuss how morphology affects the function of the peripheral ER, and how ER-phagy modulates the turnover of this organelle. We also address how ER-phagy is regulated at the molecular level, considering implications relevant to human diseases.
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Affiliation(s)
- Mohamed A Eldeeb
- McGill Parkinson Program, Neurodegenerative Diseases Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Cornelia E Zorca
- McGill Parkinson Program, Neurodegenerative Diseases Group, Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Mohamed A Ragheb
- Chemistry Department (Biochemistry Division), Faculty of Science, Cairo University, Giza, Egypt
| | - Fatma B Rashidi
- Chemistry Department (Biochemistry Division), Faculty of Science, Cairo University, Giza, Egypt
| | - Doaa S Salah El-Din
- Chemistry Department (Biochemistry Division), Faculty of Science, Cairo University, Giza, Egypt
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17
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Ke Y, Weng M, Chhetri G, Usman M, Li Y, Yu Q, Ding Y, Wang Z, Wang X, Sultana P, DiFiglia M, Li X. Trappc9 deficiency in mice impairs learning and memory by causing imbalance of dopamine D1 and D2 neurons. SCIENCE ADVANCES 2020; 6:6/47/eabb7781. [PMID: 33208359 PMCID: PMC7673810 DOI: 10.1126/sciadv.abb7781] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 10/01/2020] [Indexed: 05/06/2023]
Abstract
Genetic mutations in the gene encoding transport protein particle complex 9 (trappc9), a subunit of TRAPP that acts as a guanine nucleotide exchange factor for rab proteins, cause intellectual disability with brain structural malformations by elusive mechanisms. Here, we report that trappc9-deficient mice exhibit a broad range of behavioral deficits and postnatal delay in growth of the brain. Contrary to volume decline of various brain structures, the striatum of trappc9 null mice was enlarged. An imbalance existed between dopamine D1 and D2 receptor containing neurons in the brain of trappc9-deficient mice; pharmacological manipulation of dopamine receptors improved performances of trappc9 null mice to levels of wild-type mice on cognitive tasks. Loss of trappc9 compromised the activation of rab11 in the brain and resulted in retardation of endocytic receptor recycling in neurons. Our study elicits a pathogenic mechanism and a potential treatment for trappc9-linked disorders including intellectual disability.
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Affiliation(s)
- Yuting Ke
- School of Pharmacy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240, China
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Meiqian Weng
- Mucosal Immunology Laboratory, Combined Program in Pediatric Gastroenterology and Nutrition, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Gaurav Chhetri
- School of Pharmacy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240, China
| | - Muhammad Usman
- School of Pharmacy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240, China
| | - Yan Li
- School of Pharmacy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240, China
| | - Qing Yu
- Department of Nephrology, Shanghai General Hospital, 650 Songjiang Road, Songjiang District, Shanghai 201620, China
| | - Yingzhuo Ding
- School of Pharmacy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240, China
| | - Zejian Wang
- School of Pharmacy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240, China
| | - Xiaolong Wang
- School of Pharmacy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240, China
| | - Pinky Sultana
- School of Pharmacy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240, China
| | - Marian DiFiglia
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
| | - Xueyi Li
- School of Pharmacy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240, China.
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA 02129, USA
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18
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Bodnar B, DeGruttola A, Zhu Y, Lin Y, Zhang Y, Mo X, Hu W. Emerging role of NIK/IKK2-binding protein (NIBP)/trafficking protein particle complex 9 (TRAPPC9) in nervous system diseases. Transl Res 2020; 224:55-70. [PMID: 32434006 PMCID: PMC7442628 DOI: 10.1016/j.trsl.2020.05.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 05/02/2020] [Accepted: 05/05/2020] [Indexed: 02/05/2023]
Abstract
NFκB signaling and protein trafficking network play important roles in various biological and pathological processes. NIK-and-IKK2-binding protein (NIBP), also known as trafficking protein particle complex 9 (TRAPPC9), is a prototype member of a novel protein family, and has been shown to regulate both NFκB signaling pathway and protein transport/trafficking. NIBP is extensively expressed in the nervous system and plays an important role in regulating neurogenesis and neuronal differentiation. NIBP/TRAPPC9 mutations have been linked to an autosomal recessive intellectual disability syndrome, called NIBP Syndrome, which is characterized by nonsyndromic autosomal recessive intellectual disability along with other symptoms such as obesity, microcephaly, and facial dysmorphia. As more cases of NIBP Syndrome are identified, new light is being shed on the role of NIBP/TRAPPC9 in the central nervous system developments and diseases. NIBP is also involved in the enteric nervous system. This review will highlight the importance of NIBP/TRAPPC9 in central and enteric nervous system diseases, and the established possible mechanisms for developing a potential therapeutic.
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Affiliation(s)
- Brittany Bodnar
- Center for Metabolic Disease Research, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania; MD/PhD and Biomedical Sciences Graduate Program, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania
| | - Arianna DeGruttola
- Center for Metabolic Disease Research, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania; MD/PhD and Biomedical Sciences Graduate Program, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania
| | - Yuanjun Zhu
- Center for Metabolic Disease Research, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania; Department of Pathology and Laboratory Medicine, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania; Department of Molecular and Cellular Pharmacology, Peking University School of Pharmaceutical Sciences, Beijing, China
| | - Yuan Lin
- Center for Metabolic Disease Research, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania; Department of Pathology and Laboratory Medicine, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania
| | - Yonggang Zhang
- Center for Stem Cell Research and Application, Institute of Blood Transfusion, Chinese Academy of Medical Sciences & Peking Union Medical College (CAMS & PUMC), Chengdu, China
| | - Xianming Mo
- Laboratory of Stem Cell Biology, State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu, China
| | - Wenhui Hu
- Center for Metabolic Disease Research, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania; MD/PhD and Biomedical Sciences Graduate Program, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania; Department of Pathology and Laboratory Medicine, Temple University Lewis Katz School of Medicine, Philadelphia, Pennsylvania.
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19
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Kaur P, Kadavigere R, Girisha KM, Shukla A. Recurrent bi-allelic splicing variant c.454+3A>G in TRAPPC4 is associated with progressive encephalopathy and muscle involvement. Brain 2020; 143:e29. [PMID: 32125366 DOI: 10.1093/brain/awaa046] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Affiliation(s)
- Parneet Kaur
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India
| | - Rajagopal Kadavigere
- Department of Radiodiagnosis and Imaging, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India
| | - Katta Mohan Girisha
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India
| | - Anju Shukla
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, India
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20
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Rasheed A, Gumus E, Zaki M, Johnson K, Manzoor H, LaForce G, Ross D, McEvoy-Venneri J, Stanley V, Lee S, Virani A, Ben-Omran T, Gleeson JG, Naz S, Schaffer A. Bi-allelic TTC5 variants cause delayed developmental milestones and intellectual disability. J Med Genet 2020; 58:237-246. [PMID: 32439809 DOI: 10.1136/jmedgenet-2020-106849] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 04/01/2020] [Accepted: 04/17/2020] [Indexed: 11/04/2022]
Abstract
BACKGROUND Intellectual disability syndromes (IDSs) with or without developmental delays affect up to 3% of the world population. We sought to clinically and genetically characterise a novel IDS segregating in five unrelated consanguineous families. METHODS Clinical analyses were performed for eight patients with intellectual disability (ID). Whole-exome sequencing for selected participants followed by Sanger sequencing for all available family members was completed. Identity-by-descent (IBD) mapping was carried out for patients in two Egyptian families harbouring an identical variant. RNA was extracted from blood cells of Turkish participants, followed by cDNA synthesis and real-time PCR for TTC5. RESULTS Phenotype comparisons of patients revealed shared clinical features of moderate-to-severe ID, corpus callosum agenesis, mild ventriculomegaly, simplified gyral pattern, cerebral atrophy, delayed motor and verbal milestones and hypotonia, presenting with an IDS. Four novel homozygous variants in TTC5: c.629A>G;p.(Tyr210Cys), c.692C>T;p.(Ala231Val), c.787C>T;p.(Arg263Ter) and c.1883C>T;p.(Arg395Ter) were identified in the eight patients from participating families. IBD mapping revealed that c.787C>T;p.(Arg263Ter) is a founder variant in Egypt. Missense variants c.629A>G;p.(Tyr210Cys) and c.692C>T;p.(Ala231Val) disrupt highly conserved residues of TTC5 within the fifth and sixth tetratricopeptide repeat motifs which are required for p300 interaction, while the nonsense variants are predicted to decrease TTC5 expression. Functional analysis of variant c.1883C>T;p.(Arg395Ter) showed reduced TTC5 transcript levels in accordance with nonsense-mediated decay. CONCLUSION Combining our clinical and molecular data with a recent case report, we identify the core and variable clinical features associated with TTC5 loss-of-function variants and reveal the requirement for TTC5 in human brain development and health.
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Affiliation(s)
- Arisha Rasheed
- School of Biological Sciences, University of the Punjab Quaid-i-Azam Campus, Lahore, Pakistan
| | - Evren Gumus
- Medical Genetics, Mugla Sitki Kocman University Faculty of Medicine, Mugla, Turkey.,Medical Genetics, Harran University Faculty of Medicine, Sanliurfa, Turkey
| | - Maha Zaki
- Clinical Genetic Department, National Research Centre, Cairo, Egypt
| | - Katherine Johnson
- Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, OH, USA
| | - Humera Manzoor
- School of Biological Sciences, University of the Punjab Quaid-i-Azam Campus, Lahore, Pakistan
| | - Geneva LaForce
- Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, OH, USA
| | - Danica Ross
- Rady Children's Institute for Genomic Medicine, San Diego, California, USA.,Department of Neuroscience, University of California, San Diego, La Jolla, CA, USA
| | - Jennifer McEvoy-Venneri
- Rady Children's Institute for Genomic Medicine, San Diego, California, USA.,Department of Neuroscience, University of California, San Diego, La Jolla, CA, USA
| | - Valentina Stanley
- Department of Neuroscience, University of California, San Diego, La Jolla, CA, USA
| | - Sangmoon Lee
- Rady Children's Institute for Genomic Medicine, San Diego, California, USA.,Department of Neuroscience, University of California, San Diego, La Jolla, CA, USA
| | - Abbir Virani
- Rady Children's Institute for Genomic Medicine, San Diego, California, USA.,Department of Neuroscience, University of California, San Diego, La Jolla, CA, USA
| | - Tawfeg Ben-Omran
- Clinical and Metabolic Genetics Division, Department of Pediatrics, Weill-Cornell Medical College, Hamad Medical Corporation, Doha, Qatar
| | - Joseph G Gleeson
- Rady Children's Institute for Genomic Medicine, San Diego, California, USA.,Department of Neuroscience and Pediatrics, Howard Hughes Medical Insistute, University of California, San Diego, La Jolla, CA, USA
| | - Sadaf Naz
- School of Biological Sciences, University of the Punjab Quaid-i-Azam Campus, Lahore, Pakistan
| | - Ashleigh Schaffer
- Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, OH, USA
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21
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Yarwood R, Hellicar J, Woodman PG, Lowe M. Membrane trafficking in health and disease. Dis Model Mech 2020; 13:13/4/dmm043448. [PMID: 32433026 PMCID: PMC7197876 DOI: 10.1242/dmm.043448] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Membrane trafficking pathways are essential for the viability and growth of cells, and play a major role in the interaction of cells with their environment. In this At a Glance article and accompanying poster, we outline the major cellular trafficking pathways and discuss how defects in the function of the molecular machinery that mediates this transport lead to various diseases in humans. We also briefly discuss possible therapeutic approaches that may be used in the future treatment of trafficking-based disorders. Summary: This At a Glance article and poster summarise the major intracellular membrane trafficking pathways and associated molecular machineries, and describe how defects in these give rise to disease in humans.
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Affiliation(s)
- Rebecca Yarwood
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PT, UK
| | - John Hellicar
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PT, UK
| | - Philip G Woodman
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PT, UK
| | - Martin Lowe
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, M13 9PT, UK
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22
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Gass JM, Head BB, Shields SM, Stevenson RE, Louie RJ. Hydrocephaly associated with compound heterozygous alterations in TRAPPC12. Birth Defects Res 2020; 112:1028-1034. [PMID: 32347653 DOI: 10.1002/bdr2.1699] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 04/13/2020] [Accepted: 04/15/2020] [Indexed: 11/06/2022]
Abstract
BACKGROUND Hydrocephalus is characterized by increased cerebrospinal fluid within the brain, a causally heterogeneous disorder estimated to affect 1 per 1,000 live births, with the most severe cases often leading to fetal demise. The large number of known genetic and environmental factors that contribute to hydrocephalus makes the differential diagnosis challenging. CASES Three consecutive pregnancies of an unrelated couple were found by ultrasound to carry fetuses with hydrocephaly. DNA from two affected fetuses and the parents were subjected to whole exome sequencing. Heterozygous alterations in the TRAPPC12 gene were identified in the parents and compound heterozygous alterations were present in the two affected fetuses. The variant from the father (c.954del) leads to a premature termination of the transcript; the variant from the mother (c.1677+5G>A) affects a splice site which leads to aberrant splicing of the TRAPPC12 transcript. CONCLUSION Compound heterozygous variants in TRAPPC12, which encodes a protein involved in Golgi trafficking and mitosis, may disrupt normal brain embryogenesis leading to hydrocephalus and recurrent pregnancy loss.
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Affiliation(s)
- Jennifer M Gass
- J.C. Self Research Institute of Human Genetics, Greenwood Genetic Center, Greenwood, South Carolina, USA
| | - Barbara B Head
- Maternal-Fetal Medicine Division, Department of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Sally M Shields
- Maternal-Fetal Medicine Division, Department of Obstetrics and Gynecology, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Roger E Stevenson
- J.C. Self Research Institute of Human Genetics, Greenwood Genetic Center, Greenwood, South Carolina, USA
| | - Raymond J Louie
- J.C. Self Research Institute of Human Genetics, Greenwood Genetic Center, Greenwood, South Carolina, USA
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23
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Liang JR, Lingeman E, Luong T, Ahmed S, Muhar M, Nguyen T, Olzmann JA, Corn JE. A Genome-wide ER-phagy Screen Highlights Key Roles of Mitochondrial Metabolism and ER-Resident UFMylation. Cell 2020; 180:1160-1177.e20. [PMID: 32160526 DOI: 10.1016/j.cell.2020.02.017] [Citation(s) in RCA: 150] [Impact Index Per Article: 37.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 11/04/2019] [Accepted: 02/07/2020] [Indexed: 12/13/2022]
Abstract
Selective autophagy of organelles is critical for cellular differentiation, homeostasis, and organismal health. Autophagy of the ER (ER-phagy) is implicated in human neuropathy but is poorly understood beyond a few autophagosomal receptors and remodelers. By using an ER-phagy reporter and genome-wide CRISPRi screening, we identified 200 high-confidence human ER-phagy factors. Two pathways were unexpectedly required for ER-phagy. First, reduced mitochondrial metabolism represses ER-phagy, which is opposite of general autophagy and is independent of AMPK. Second, ER-localized UFMylation is required for ER-phagy to repress the unfolded protein response via IRE1α. The UFL1 ligase is brought to the ER surface by DDRGK1 to UFMylate RPN1 and RPL26 and preferentially targets ER sheets for degradation, analogous to PINK1-Parkin regulation during mitophagy. Our data provide insight into the cellular logic of ER-phagy, reveal parallels between organelle autophagies, and provide an entry point to the relatively unexplored process of degrading the ER network.
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Affiliation(s)
- Jin Rui Liang
- Innovative Genomics Institute, University of California, Berkeley, Berkeley, CA 94720, USA; Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Department of Biology, ETH Zürich, 8093 Zürich, Switzerland
| | - Emily Lingeman
- Innovative Genomics Institute, University of California, Berkeley, Berkeley, CA 94720, USA; Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Thao Luong
- Innovative Genomics Institute, University of California, Berkeley, Berkeley, CA 94720, USA; Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Saba Ahmed
- Innovative Genomics Institute, University of California, Berkeley, Berkeley, CA 94720, USA; Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Matthias Muhar
- Department of Biology, ETH Zürich, 8093 Zürich, Switzerland
| | - Truc Nguyen
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - James A Olzmann
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, Berkeley, CA 94720, USA; Chan Zuckerberg Biohub, San Francisco, CA 94158, USA
| | - Jacob E Corn
- Innovative Genomics Institute, University of California, Berkeley, Berkeley, CA 94720, USA; Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Department of Biology, ETH Zürich, 8093 Zürich, Switzerland.
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24
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Wang B, Stanford KR, Kundu M. ER-to-Golgi Trafficking and Its Implication in Neurological Diseases. Cells 2020; 9:E408. [PMID: 32053905 PMCID: PMC7073182 DOI: 10.3390/cells9020408] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 01/27/2020] [Accepted: 02/07/2020] [Indexed: 12/21/2022] Open
Abstract
Membrane and secretory proteins are essential for almost every aspect of cellular function. These proteins are incorporated into ER-derived carriers and transported to the Golgi before being sorted for delivery to their final destination. Although ER-to-Golgi trafficking is highly conserved among eukaryotes, several layers of complexity have been added to meet the increased demands of complex cell types in metazoans. The specialized morphology of neurons and the necessity for precise spatiotemporal control over membrane and secretory protein localization and function make them particularly vulnerable to defects in trafficking. This review summarizes the general mechanisms involved in ER-to-Golgi trafficking and highlights mutations in genes affecting this process, which are associated with neurological diseases in humans.
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Affiliation(s)
- Bo Wang
- Department of Pathology, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA; (B.W.); (K.R.S.)
- Department of Cell and Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA
| | - Katherine R. Stanford
- Department of Pathology, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA; (B.W.); (K.R.S.)
- Department of Cell and Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA
| | - Mondira Kundu
- Department of Pathology, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA; (B.W.); (K.R.S.)
- Department of Cell and Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN 38105, USA
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25
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Van Bergen NJ, Guo Y, Al-Deri N, Lipatova Z, Stanga D, Zhao S, Murtazina R, Gyurkovska V, Pehlivan D, Mitani T, Gezdirici A, Antony J, Collins F, Willis MJH, Coban Akdemir ZH, Liu P, Punetha J, Hunter JV, Jhangiani SN, Fatih JM, Rosenfeld JA, Posey JE, Gibbs RA, Karaca E, Massey S, Ranasinghe TG, Sleiman P, Troedson C, Lupski JR, Sacher M, Segev N, Hakonarson H, Christodoulou J. Deficiencies in vesicular transport mediated by TRAPPC4 are associated with severe syndromic intellectual disability. Brain 2020; 143:112-130. [PMID: 31794024 PMCID: PMC6935753 DOI: 10.1093/brain/awz374] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 09/20/2019] [Accepted: 10/07/2019] [Indexed: 12/11/2022] Open
Abstract
The conserved transport protein particle (TRAPP) complexes regulate key trafficking events and are required for autophagy. TRAPPC4, like its yeast Trs23 orthologue, is a core component of the TRAPP complexes and one of the essential subunits for guanine nucleotide exchange factor activity for Rab1 GTPase. Pathogenic variants in specific TRAPP subunits are associated with neurological disorders. We undertook exome sequencing in three unrelated families of Caucasian, Turkish and French-Canadian ethnicities with seven affected children that showed features of early-onset seizures, developmental delay, microcephaly, sensorineural deafness, spastic quadriparesis and progressive cortical and cerebellar atrophy in an effort to determine the genetic aetiology underlying neurodevelopmental disorders. All seven affected subjects shared the same identical rare, homozygous, potentially pathogenic variant in a non-canonical, well-conserved splice site within TRAPPC4 (hg19:chr11:g.118890966A>G; TRAPPC4: NM_016146.5; c.454+3A>G). Single nucleotide polymorphism array analysis revealed there was no haplotype shared between the tested Turkish and Caucasian families suggestive of a variant hotspot region rather than a founder effect. In silico analysis predicted the variant to cause aberrant splicing. Consistent with this, experimental evidence showed both a reduction in full-length transcript levels and an increase in levels of a shorter transcript missing exon 3, suggestive of an incompletely penetrant splice defect. TRAPPC4 protein levels were significantly reduced whilst levels of other TRAPP complex subunits remained unaffected. Native polyacrylamide gel electrophoresis and size exclusion chromatography demonstrated a defect in TRAPP complex assembly and/or stability. Intracellular trafficking through the Golgi using the marker protein VSVG-GFP-ts045 demonstrated significantly delayed entry into and exit from the Golgi in fibroblasts derived from one of the affected subjects. Lentiviral expression of wild-type TRAPPC4 in these fibroblasts restored trafficking, suggesting that the trafficking defect was due to reduced TRAPPC4 levels. Consistent with the recent association of the TRAPP complex with autophagy, we found that the fibroblasts had a basal autophagy defect and a delay in autophagic flux, possibly due to unsealed autophagosomes. These results were validated using a yeast trs23 temperature sensitive variant that exhibits constitutive and stress-induced autophagic defects at permissive temperature and a secretory defect at restrictive temperature. In summary we provide strong evidence for pathogenicity of this variant in a member of the core TRAPP subunit, TRAPPC4 that associates with vesicular trafficking and autophagy defects. This is the first report of a TRAPPC4 variant, and our findings add to the growing number of TRAPP-associated neurological disorders.
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Affiliation(s)
- Nicole J Van Bergen
- Brain and Mitochondrial Research Group, Murdoch Children’s Research Institute, Royal Children’s Hospital, Melbourne, Australia
- Department of Paediatrics, University of Melbourne, Melbourne, Australia
| | - Yiran Guo
- Center for Applied Genomics (CAG) at the Children’s Hospital of Philadelphia (CHOP), Philadelphia, USA
| | - Noraldin Al-Deri
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Zhanna Lipatova
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, IL, USA
| | - Daniela Stanga
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Sarah Zhao
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, IL, USA
| | - Rakhilya Murtazina
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, IL, USA
| | - Valeriya Gyurkovska
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, IL, USA
| | - Davut Pehlivan
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030, USA
- Section of Pediatric Neurology and Developmental Neuroscience, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, 77030, USA
| | - Tadahiro Mitani
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030, USA
| | - Alper Gezdirici
- Department of Medical Genetics, Kanuni Sultan Suleyman Training and Research Hospital, Istanbul, 34303, Turkey
| | - Jayne Antony
- TY Nelson Department of Neurology and Neurosurgery, Children’s Hospital at Westmead, Sydney, Australia
| | - Felicity Collins
- Western Sydney Genetics Program, Children’s Hospital at Westmead, Sydney, Australia
- Medical Genomics Department, Royal Prince Alfred Hospital, Sydney, Australia
| | - Mary J H Willis
- Department of Pediatrics, Naval Medical Center San Diego, San Diego, California, USA
| | - Zeynep H Coban Akdemir
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030, USA
| | - Pengfei Liu
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030, USA
| | - Jaya Punetha
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030, USA
| | - Jill V Hunter
- Department of Radiology, Baylor College of Medicine, Houston, Texas, 77030, USA
| | - Shalini N Jhangiani
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, Texas, USA
| | - Jawid M Fatih
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030, USA
| | - Jill A Rosenfeld
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030, USA
| | - Jennifer E Posey
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030, USA
| | - Richard A Gibbs
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030, USA
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, Texas, USA
| | - Ender Karaca
- Department of Genetics, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Sean Massey
- Brain and Mitochondrial Research Group, Murdoch Children’s Research Institute, Royal Children’s Hospital, Melbourne, Australia
| | - Thisara G Ranasinghe
- Brain and Mitochondrial Research Group, Murdoch Children’s Research Institute, Royal Children’s Hospital, Melbourne, Australia
| | - Patrick Sleiman
- Center for Applied Genomics (CAG) at the Children’s Hospital of Philadelphia (CHOP), Philadelphia, USA
| | - Chris Troedson
- TY Nelson Department of Neurology and Neurosurgery, Children’s Hospital at Westmead, Sydney, Australia
| | - James R Lupski
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, 77030, USA
- Human Genome Sequencing Center, Baylor College of Medicine, Houston, Texas, USA
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas, 77030, USA
- Texas Children’s Hospital, Houston, Texas, 77030, USA
| | - Michael Sacher
- Department of Biology, Concordia University, Montreal, Quebec, Canada
- Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec, Canada
| | - Nava Segev
- Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, IL, USA
| | - Hakon Hakonarson
- Center for Applied Genomics (CAG) at the Children’s Hospital of Philadelphia (CHOP), Philadelphia, USA
| | - John Christodoulou
- Brain and Mitochondrial Research Group, Murdoch Children’s Research Institute, Royal Children’s Hospital, Melbourne, Australia
- Department of Paediatrics, University of Melbourne, Melbourne, Australia
- Victorian Clinical Genetics Services, Royal Children’s Hospital, VIC, Australia
- Kids Research, The Children’s Hospital at Westmead, Sydney, NSW, Australia
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26
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Passemard S, Perez F, Gressens P, El Ghouzzi V. Endoplasmic reticulum and Golgi stress in microcephaly. Cell Stress 2019; 3:369-384. [PMID: 31832602 PMCID: PMC6883743 DOI: 10.15698/cst2019.12.206] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Microcephaly is a neurodevelopmental condition characterized by a small brain size associated with intellectual deficiency in most cases and is one of the most frequent clinical sign encountered in neurodevelopmental disorders. It can result from a wide range of environmental insults occurring during pregnancy or postnatally, as well as from various genetic causes and represents a highly heterogeneous condition. However, several lines of evidence highlight a compromised mode of division of the cortical precursor cells during neurogenesis, affecting neural commitment or survival as one of the common mechanisms leading to a limited production of neurons and associated with the most severe forms of congenital microcephaly. In this context, the emergence of the endoplasmic reticulum (ER) and the Golgi apparatus as key guardians of cellular homeostasis, especially through the regulation of proteostasis, has raised the hypothesis that pathological ER and/or Golgi stress could contribute significantly to cortical impairments eliciting microcephaly. In this review, we discuss recent findings implicating ER and Golgi stress responses in early brain development and provide an overview of microcephaly-associated genes involved in these pathways.
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Affiliation(s)
- Sandrine Passemard
- Université de Paris, NeuroDiderot, Inserm, F-75019 Paris, France.,Service de Génétique Clinique, AP-HP, Hôpital Robert Debré, F-75019 Paris, France
| | - Franck Perez
- Institut Curie, PSL Research University, CNRS, UMR144, Paris, France
| | - Pierre Gressens
- Université de Paris, NeuroDiderot, Inserm, F-75019 Paris, France.,Centre for the Developing Brain, Division of Imaging Sciences and Biomedical Engineering, King's College London, King's Health Partners, St. Thomas'Hospital, London, United Kingdom
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27
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Milev MP, Stanga D, Schänzer A, Nascimento A, Saint-Dic D, Ortez C, Natera-de Benito D, Barrios DG, Colomer J, Badosa C, Jou C, Gallano P, Gonzalez-Quereda L, Töpf A, Johnson K, Straub V, Hahn A, Sacher M, Jimenez-Mallebrera C. Characterization of three TRAPPC11 variants suggests a critical role for the extreme carboxy terminus of the protein. Sci Rep 2019; 9:14036. [PMID: 31575891 PMCID: PMC6773699 DOI: 10.1038/s41598-019-50415-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 09/11/2019] [Indexed: 12/23/2022] Open
Abstract
TRAPPC11 was identified as a component of the TRAPP III complex that functions in membrane trafficking and autophagy. Variants in TRAPPC11 have been reported to be associated with a broad spectrum of phenotypes but all affected individuals display muscular pathology. Identifying additional variants will further our understanding of the clinical spectrum of phenotypes and will reveal regions of the protein critical for its functions. Here we report three individuals from unrelated families that have bi-allellic TRAPPC11 variants. Subject 1 harbors a compound heterozygous variant (c.1287 + 5G > A and c.3379_3380insT). The former variant results in a partial deletion of the foie gras domain (p.Ala372_Ser429del), while the latter variant results in a frame-shift and extension at the carboxy terminus (p.Asp1127Valfs*47). Subjects 2 and 3 both harbour a homozygous missense variant (c.2938G > A; p.Gly980Arg). Fibroblasts from all three subjects displayed membrane trafficking defects manifested as delayed endoplasmic reticulum (ER)-to-Golgi transport and/or a delay in protein exit from the Golgi. All three individuals also show a defect in glycosylation of an ER-resident glycoprotein. However, only the compound heterozygous subject displayed an autophagic flux defect. Collectively, our characterization of these individuals with bi-allelic TRAPPC11 variants highlights the functional importance of the carboxy-terminal portion of the protein.
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Affiliation(s)
- Miroslav P Milev
- Concordia University, Department of Biology, Montreal, Quebec, Canada
| | - Daniela Stanga
- Concordia University, Department of Biology, Montreal, Quebec, Canada
| | - Anne Schänzer
- Institute of Neuropathology, Justus Liebig University Giessen, Giessen, Germany
| | - Andrés Nascimento
- Neuromuscular Unit, Neuropaediatrics Department, Hospital Sant Joan de Déu, Institut de Recerca Sant Joan de Déu, Barcelona, Spain.,U705 and U703 Center for Biomedical Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Djenann Saint-Dic
- Concordia University, Department of Biology, Montreal, Quebec, Canada
| | - Carlos Ortez
- Neuromuscular Unit, Neuropaediatrics Department, Hospital Sant Joan de Déu, Institut de Recerca Sant Joan de Déu, Barcelona, Spain
| | - Daniel Natera-de Benito
- Neuromuscular Unit, Neuropaediatrics Department, Hospital Sant Joan de Déu, Institut de Recerca Sant Joan de Déu, Barcelona, Spain
| | - Desiré González Barrios
- Servicio de Pediatría, Hospital Universitario Nuestra Señora de Candelaria, Santa Cruz de Tenerife, Spain
| | - Jaume Colomer
- Neuromuscular Unit, Neuropaediatrics Department, Hospital Sant Joan de Déu, Institut de Recerca Sant Joan de Déu, Barcelona, Spain
| | - Carmen Badosa
- Neuromuscular Unit, Neuropaediatrics Department, Hospital Sant Joan de Déu, Institut de Recerca Sant Joan de Déu, Barcelona, Spain
| | - Cristina Jou
- U705 and U703 Center for Biomedical Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain.,Pathology Department and Biobank, Hospital Sant Joan de Déu, Institut de Recerca Sant Joan de Déu, Barcelona, Spain
| | - Pia Gallano
- U705 and U703 Center for Biomedical Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain.,Servicio de Genética, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - Lidia Gonzalez-Quereda
- U705 and U703 Center for Biomedical Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain.,Servicio de Genética, Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
| | - Ana Töpf
- The John Walton Muscular Dystrophy Research Centre, Institute of Genetic Medicine, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle-upon-Tyne, UK
| | - Katherine Johnson
- The John Walton Muscular Dystrophy Research Centre, Institute of Genetic Medicine, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle-upon-Tyne, UK.,Institute of Cellular Medicine, Newcastle University, Newcastle-upon-Tyne, UK
| | - Volker Straub
- The John Walton Muscular Dystrophy Research Centre, Institute of Genetic Medicine, Newcastle University and Newcastle Hospitals NHS Foundation Trust, Newcastle-upon-Tyne, UK
| | - Andreas Hahn
- Department of Child Neurology, Justus Liebig University Giessen, Giessen, Germany.
| | - Michael Sacher
- Concordia University, Department of Biology, Montreal, Quebec, Canada. .,McGill University, Department of Anatomy and Cell Biology, Montreal, Quebec, Canada.
| | - Cecilia Jimenez-Mallebrera
- Neuromuscular Unit, Neuropaediatrics Department, Hospital Sant Joan de Déu, Institut de Recerca Sant Joan de Déu, Barcelona, Spain. .,U705 and U703 Center for Biomedical Research on Rare Diseases (CIBERER), Instituto de Salud Carlos III, Madrid, Spain.
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28
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Zappa F, Wilson C, Di Tullio G, Santoro M, Pucci P, Monti M, D'Amico D, Pisonero-Vaquero S, De Cegli R, Romano A, Saleem MA, Polishchuk E, Failli M, Giaquinto L, De Matteis MA. The TRAPP complex mediates secretion arrest induced by stress granule assembly. EMBO J 2019; 38:e101704. [PMID: 31429971 DOI: 10.15252/embj.2019101704] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Revised: 07/31/2019] [Accepted: 08/01/2019] [Indexed: 12/29/2022] Open
Abstract
The TRAnsport Protein Particle (TRAPP) complex controls multiple membrane trafficking steps and is strategically positioned to mediate cell adaptation to diverse environmental conditions, including acute stress. We have identified the TRAPP complex as a component of a branch of the integrated stress response that impinges on the early secretory pathway. The TRAPP complex associates with and drives the recruitment of the COPII coat to stress granules (SGs) leading to vesiculation of the Golgi complex and arrest of ER export. The relocation of the TRAPP complex and COPII to SGs only occurs in cycling cells and is CDK1/2-dependent, being driven by the interaction of TRAPP with hnRNPK, a CDK substrate that associates with SGs when phosphorylated. In addition, CDK1/2 inhibition impairs TRAPP complex/COPII relocation to SGs while stabilizing them at ER exit sites. Importantly, the TRAPP complex controls the maturation of SGs. SGs that assemble in TRAPP-depleted cells are smaller and are no longer able to recruit RACK1 and Raptor, two TRAPP-interactive signaling proteins, sensitizing cells to stress-induced apoptosis.
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Affiliation(s)
- Francesca Zappa
- Telethon Institute of Genetics and Medicine, Pozzuoli (Naples), Italy
| | - Cathal Wilson
- Telethon Institute of Genetics and Medicine, Pozzuoli (Naples), Italy
| | | | - Michele Santoro
- Telethon Institute of Genetics and Medicine, Pozzuoli (Naples), Italy
| | | | | | - Davide D'Amico
- Telethon Institute of Genetics and Medicine, Pozzuoli (Naples), Italy
| | | | - Rossella De Cegli
- Telethon Institute of Genetics and Medicine, Pozzuoli (Naples), Italy
| | - Alessia Romano
- Telethon Institute of Genetics and Medicine, Pozzuoli (Naples), Italy
| | - Moin A Saleem
- Bristol Renal, Bristol Medical School, University of Bristol, Bristol, UK
| | - Elena Polishchuk
- Telethon Institute of Genetics and Medicine, Pozzuoli (Naples), Italy
| | - Mario Failli
- Telethon Institute of Genetics and Medicine, Pozzuoli (Naples), Italy
| | - Laura Giaquinto
- Telethon Institute of Genetics and Medicine, Pozzuoli (Naples), Italy
| | - Maria Antonietta De Matteis
- Telethon Institute of Genetics and Medicine, Pozzuoli (Naples), Italy.,Federico II University, Naples, Italy
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29
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Stanga D, Zhao Q, Milev MP, Saint-Dic D, Jimenez-Mallebrera C, Sacher M. TRAPPC11 functions in autophagy by recruiting ATG2B-WIPI4/WDR45 to preautophagosomal membranes. Traffic 2019; 20:325-345. [PMID: 30843302 DOI: 10.1111/tra.12640] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Revised: 03/04/2019] [Accepted: 03/05/2019] [Indexed: 01/01/2023]
Abstract
TRAPPC11 has been implicated in membrane traffic and lipid-linked oligosaccharide synthesis, and mutations in TRAPPC11 result in neuromuscular and developmental phenotypes. Here, we show that TRAPPC11 has a role upstream of autophagosome formation during macroautophagy. Upon TRAPPC11 depletion, LC3-positive membranes accumulate prior to, and fail to be cleared during, starvation. A proximity biotinylation assay identified ATG2B and its binding partner WIPI4/WDR45 as TRAPPC11 interactors. TRAPPC11 depletion phenocopies that of ATG2 and WIPI4 and recruitment of both proteins to membranes is defective upon reduction of TRAPPC11. We find that a portion of TRAPPC11 and other TRAPP III proteins localize to isolation membranes. Fibroblasts from a patient with TRAPPC11 mutations failed to recruit ATG2B-WIPI4, suggesting that this interaction is physiologically relevant. Since ATG2B-WIPI4 is required for isolation membrane expansion, our study suggests that TRAPPC11 plays a role in this process. We propose a model whereby the TRAPP III complex participates in the formation and expansion of the isolation membrane at several steps.
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Affiliation(s)
- Daniela Stanga
- Concordia University, Department of Biology, Montreal, Quebec, Canada
| | - Qingchuan Zhao
- University of Montreal, Department of Medicine and Institute for Research in Immunology and Cancer, Montreal, Quebec, Canada
| | - Miroslav P Milev
- Concordia University, Department of Biology, Montreal, Quebec, Canada
| | - Djenann Saint-Dic
- Concordia University, Department of Biology, Montreal, Quebec, Canada
| | - Cecilia Jimenez-Mallebrera
- Neuromuscular Unit, Neuropaediatrics Department, Institut de Recerca Sant Joan de Déu, Hospital Sant Joan de Déu and CIBERER, Barcelona, Spain
| | - Michael Sacher
- Concordia University, Department of Biology, Montreal, Quebec, Canada.,McGill University, Department of Anatomy and Cell Biology, Quebec, Canada
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30
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Rasika S, Passemard S, Verloes A, Gressens P, El Ghouzzi V. Golgipathies in Neurodevelopment: A New View of Old Defects. Dev Neurosci 2019; 40:396-416. [PMID: 30878996 DOI: 10.1159/000497035] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 01/16/2019] [Indexed: 11/19/2022] Open
Abstract
The Golgi apparatus (GA) is involved in a whole spectrum of activities, from lipid biosynthesis and membrane secretion to the posttranslational processing and trafficking of most proteins, the control of mitosis, cell polarity, migration and morphogenesis, and diverse processes such as apoptosis, autophagy, and the stress response. In keeping with its versatility, mutations in GA proteins lead to a number of different disorders, including syndromes with multisystem involvement. Intriguingly, however, > 40% of the GA-related genes known to be associated with disease affect the central or peripheral nervous system, highlighting the critical importance of the GA for neural function. We have previously proposed the term "Golgipathies" in relation to a group of disorders in which mutations in GA proteins or their molecular partners lead to consequences for brain development, in particular postnatal-onset microcephaly (POM), white-matter defects, and intellectual disability (ID). Here, taking into account the broader role of the GA in the nervous system, we refine and enlarge this emerging concept to include other disorders whose symptoms may be indicative of altered neurodevelopmental processes, from neurogenesis to neuronal migration and the secretory function critical for the maturation of postmitotic neurons and myelination.
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Affiliation(s)
- Sowmyalakshmi Rasika
- NeuroDiderot, INSERM UMR1141, Université Paris Diderot, Sorbonne Paris Cité, Paris, France.,AP HP, Hôpital Robert Debré, UF de Génétique Clinique, Paris, France
| | - Sandrine Passemard
- NeuroDiderot, INSERM UMR1141, Université Paris Diderot, Sorbonne Paris Cité, Paris, France.,AP HP, Hôpital Robert Debré, UF de Génétique Clinique, Paris, France
| | - Alain Verloes
- NeuroDiderot, INSERM UMR1141, Université Paris Diderot, Sorbonne Paris Cité, Paris, France.,AP HP, Hôpital Robert Debré, UF de Génétique Clinique, Paris, France
| | - Pierre Gressens
- NeuroDiderot, INSERM UMR1141, Université Paris Diderot, Sorbonne Paris Cité, Paris, France.,Centre for the Developing Brain, Division of Imaging Sciences and Biomedical Engineering, King's College London, King's Health Partners, St. Thomas' Hospital, London, United Kingdom
| | - Vincent El Ghouzzi
- NeuroDiderot, INSERM UMR1141, Université Paris Diderot, Sorbonne Paris Cité, Paris, France,
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31
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Sacher M, Shahrzad N, Kamel H, Milev MP. TRAPPopathies: An emerging set of disorders linked to variations in the genes encoding transport protein particle (TRAPP)-associated proteins. Traffic 2018; 20:5-26. [PMID: 30152084 DOI: 10.1111/tra.12615] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 08/23/2018] [Accepted: 08/26/2018] [Indexed: 02/06/2023]
Abstract
The movement of proteins between cellular compartments requires the orchestrated actions of many factors including Rab family GTPases, Soluble NSF Attachment protein REceptors (SNAREs) and so-called tethering factors. One such tethering factor is called TRAnsport Protein Particle (TRAPP), and in humans, TRAPP proteins are distributed into two related complexes called TRAPP II and III. Although thought to act as a single unit within the complex, in the past few years it has become evident that some TRAPP proteins function independently of the complex. Consistent with this, variations in the genes encoding these proteins result in a spectrum of human diseases with diverse, but partially overlapping, phenotypes. This contrasts with other tethering factors such as COG, where variations in the genes that encode its subunits all result in an identical phenotype. In this review, we present an up-to-date summary of all the known disease-related variations of genes encoding TRAPP-associated proteins and the disorders linked to these variations which we now call TRAPPopathies.
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Affiliation(s)
- Michael Sacher
- Department of Biology, Concordia University, Montreal, Quebec, Canada.,Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec, Canada
| | - Nassim Shahrzad
- Department of Medicine, University of California, San Francisco, California
| | - Hiba Kamel
- Department of Biology, Concordia University, Montreal, Quebec, Canada
| | - Miroslav P Milev
- Department of Biology, Concordia University, Montreal, Quebec, Canada
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32
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Milev MP, Graziano C, Karall D, Kuper WFE, Al-Deri N, Cordelli DM, Haack TB, Danhauser K, Iuso A, Palombo F, Pippucci T, Prokisch H, Saint-Dic D, Seri M, Stanga D, Cenacchi G, van Gassen KLI, Zschocke J, Fauth C, Mayr JA, Sacher M, van Hasselt PM. Bi-allelic mutations in TRAPPC2L result in a neurodevelopmental disorder and have an impact on RAB11 in fibroblasts. J Med Genet 2018; 55:753-764. [DOI: 10.1136/jmedgenet-2018-105441] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 06/18/2018] [Accepted: 07/12/2018] [Indexed: 12/28/2022]
Abstract
BackgroundThe combination of febrile illness-induced encephalopathy and rhabdomyolysis has thus far only been described in disorders that affect cellular energy status. In the absence of specific metabolic abnormalities, diagnosis can be challenging.ObjectiveThe objective of this study was to identify and characterise pathogenic variants in two individuals from unrelated families, both of whom presented clinically with a similar phenotype that included neurodevelopmental delay, febrile illness-induced encephalopathy and episodes of rhabdomyolysis, followed by developmental arrest, epilepsy and tetraplegia.MethodsWhole exome sequencing was used to identify pathogenic variants in the two individuals. Biochemical and cell biological analyses were performed on fibroblasts from these individuals and a yeast two-hybrid analysis was used to assess protein-protein interactions.ResultsProbands shared a homozygous TRAPPC2L variant (c.109G>T) resulting in a p.Asp37Tyr missense variant. TRAPPC2L is a component of transport protein particle (TRAPP), a group of multisubunit complexes that function in membrane traffic and autophagy. Studies in patient fibroblasts as well as in a yeast system showed that the p.Asp37Tyr protein was present but not functional and resulted in specific membrane trafficking delays. The human missense mutation and the analogous mutation in the yeast homologue Tca17 ablated the interaction between TRAPPC2L and TRAPPC10/Trs130, a component of the TRAPP II complex. Since TRAPP II activates the GTPase RAB11, we examined the activation state of this protein and found increased levels of the active RAB, correlating with changes in its cellular morphology.ConclusionsOur study implicates a RAB11 pathway in the aetiology of the TRAPPC2L disorder and has implications for other TRAPP-related disorders with similar phenotypes.
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