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Noojarern S, Tim-Aroon T, Anurat K, Phetthong T, Khongkraparn A, Wattanasirichaigoon D. A novel AP1S2 variant causing leaky splicing in X-linked intellectual disability: Further delineation and intrafamilial variability. Am J Med Genet A 2024; 194:e63639. [PMID: 38682877 DOI: 10.1002/ajmg.a.63639] [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: 11/14/2023] [Revised: 04/07/2024] [Accepted: 04/11/2024] [Indexed: 05/01/2024]
Abstract
Pettigrew syndrome (PGS), an X-linked intellectual disability (XLID), is caused by mutations in the AP1S2 gene. Herein, we described a Thai family with six patients who had severe-to-profound intellectual impairment, limited verbal communication, and varying degrees of limb spasticity. One patient had a unilateral cataract. We demonstrated facial evolution over time, namely coarse facies, long faces, and thick lip vermilions. We identified a novel AP1S2 variant, c.1-2A>G. The mRNA analysis revealed that the variant resulted in splicing defects with leaky splicing, yielding two distinct aberrant transcripts, one of which likely resulting in the mutant protein lacking the first 44 amino acids whereas the other possibly leading to no production of the protein. By performing a literature review, we found 51 patients and 11 AP1S2 pathogenic alleles described and that all the variants were loss-of-function alleles. The severity of ID in Pettigrew syndrome is mostly severe-to-profound (54.8%), followed by moderate (26.2%) and mild. Progressive spasticity was noted in multiple patients. In summary, leaky splicing found in the present family was likely related to the intrafamilial clinical variability. Our data also support the previous notion of variable expression and neuroprogressive nature of the disorder.
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Affiliation(s)
- Saisuda Noojarern
- Division of Medical Genetics, Department of Pediatrics, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | - Thipwimol Tim-Aroon
- Division of Medical Genetics, Department of Pediatrics, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | - Kingthong Anurat
- Chakri Naruebodindra Medical Institute, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Samut Prakan, Thailand
| | - Tim Phetthong
- Division of Medical Genetics, Department of Pediatrics, Phramongkutklao Hospital and Phramongkutklao College of Medicine, Bangkok, Thailand
| | - Arthaporn Khongkraparn
- Division of Medical Genetics, Department of Pediatrics, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | - Duangrurdee Wattanasirichaigoon
- Division of Medical Genetics, Department of Pediatrics, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
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Smith IR, Hendricks EL, Latcheva NK, Marenda DR, Liebl FLW. The CHD Protein Kismet Restricts the Synaptic Localization of Cell Adhesion Molecules at the Drosophila Neuromuscular Junction. Int J Mol Sci 2024; 25:3074. [PMID: 38474321 PMCID: PMC10931923 DOI: 10.3390/ijms25053074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2024] [Revised: 03/01/2024] [Accepted: 03/05/2024] [Indexed: 03/14/2024] Open
Abstract
The appropriate expression and localization of cell surface cell adhesion molecules must be tightly regulated for optimal synaptic growth and function. How neuronal plasma membrane proteins, including cell adhesion molecules, cycle between early endosomes and the plasma membrane is poorly understood. Here we show that the Drosophila homolog of the chromatin remodeling enzymes CHD7 and CHD8, Kismet, represses the synaptic levels of several cell adhesion molecules. Neuroligins 1 and 3 and the integrins αPS2 and βPS are increased at kismet mutant synapses but Kismet only directly regulates transcription of neuroligin 2. Kismet may therefore regulate synaptic CAMs indirectly by activating transcription of gene products that promote intracellular vesicle trafficking including endophilin B (endoB) and/or rab11. Knock down of EndoB in all tissues or neurons increases synaptic FasII while knock down of EndoB in kis mutants does not produce an additive increase in FasII. In contrast, neuronal expression of Rab11, which is deficient in kis mutants, leads to a further increase in synaptic FasII in kis mutants. These data support the hypothesis that Kis influences the synaptic localization of FasII by promoting intracellular vesicle trafficking through the early endosome.
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Affiliation(s)
- Ireland R. Smith
- Department of Biological Sciences, Southern Illinois University Edwardsville, Edwardsville, IL 62025, USA
| | - Emily L. Hendricks
- Department of Biological Sciences, Southern Illinois University Edwardsville, Edwardsville, IL 62025, USA
| | - Nina K. Latcheva
- Department of Biology, Drexel University, 3141 Chestnut St., Philadelphia, PA 19104, USA (D.R.M.)
- Program in Molecular and Cellular Biology and Genetics, Drexel University College of Medicine, Philadelphia, PA 19104, USA
- Neurogenetics Program, Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
| | - Daniel R. Marenda
- Department of Biology, Drexel University, 3141 Chestnut St., Philadelphia, PA 19104, USA (D.R.M.)
- Program in Molecular and Cellular Biology and Genetics, Drexel University College of Medicine, Philadelphia, PA 19104, USA
- Division of Biological Infrastructure, National Science Foundation, Alexandria, VA 22314, USA
| | - Faith L. W. Liebl
- Department of Biological Sciences, Southern Illinois University Edwardsville, Edwardsville, IL 62025, USA
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Sengül GF, Mishra R, Candiello E, Schu P. Hsc70 phosphorylation patterns and calmodulin regulate AP2 Clathrin-Coated-Vesicle life span for cell adhesion protein transport. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2024; 1871:119611. [PMID: 37926156 DOI: 10.1016/j.bbamcr.2023.119611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 10/17/2023] [Accepted: 10/17/2023] [Indexed: 11/07/2023]
Abstract
AP2 forms AP2 CCV with clathrin and over 60 additional coat proteins. Due to this complexity, we have a limited understanding of CCV life cycle regulation. Synapses contain canonical AP2 CCV, canCCV, and more stable, thereby longer lived, AP2 CCV. The more stable AP2 CCV can be distinguished from canCCV due to the stable binding of Hsc70 to clathrin. The AP1/σ1B complex knockout leads to impaired synaptic vesicle recycling and altered endosomal protein sorting. This causes as a secondary phenotype the twofold upregulation of endocytosis by canCCV and by more stable AP2 CCV. These stable CCV are more stabilized than their wt counterpart, hence stCCV. They have less of the uncoating proteins synaptojanin1 and Hsc70, and more of the coat stabilizing AAK1. Hsc70 clathrin dissociation activity is regulated by complex phosphorylation patterns. Two major groups of hyper- and of hypo-phosphorylated Hsc70 proteins are formed. The latter are enriched in wt stable CCV and stabilized stCCV. Hsc70 T265 phosphorylation regulates binding of CaM/Ca2+. CaM/Ca2+ binding to the T265 domain blocks Hsc70 homodimerization and its concentration in stCCV required for clathrin disassembly. Kinases DYRK1A and CaMK-IIδ can phosphorylate T265 preventing CaM/Ca2+ binding. Their and the levels of STK38L and STK39/Cab39, which are able to phosphorylate additional Hsc70 residues are reduced in stCCV. The stCCV pathway sorts specifically the cell adhesion proteins CHL1 and Neurocan, supporting our model of that the stCCV pathway fulfills specific functions in synaptic plasticity.
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Affiliation(s)
- G F Sengül
- Georg-August-University Göttingen, University Medical Center, Department of Cellular Biochemistry, Humboldtallee 23, 37073 Göttingen, Germany; Ankara Medipol University, Faculty of Medicine, Department of Medical Biochemistry, Turkey
| | - R Mishra
- Georg-August-University Göttingen, University Medical Center, Department of Cellular Biochemistry, Humboldtallee 23, 37073 Göttingen, Germany; Dept. of Clinical Neurosciences, John van Geest Centre for Brain Repair, University of Cambridge, England, United Kingdom
| | - E Candiello
- Georg-August-University Göttingen, University Medical Center, Department of Cellular Biochemistry, Humboldtallee 23, 37073 Göttingen, Germany; University of Turin, Tumor Immunology Laboratory, Torino, Italy
| | - P Schu
- Georg-August-University Göttingen, University Medical Center, Department of Cellular Biochemistry, Humboldtallee 23, 37073 Göttingen, Germany.
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4
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Obata Y, Kurokawa K, Tojima T, Natsume M, Shiina I, Takahashi T, Abe R, Nakano A, Nishida T. Golgi retention and oncogenic KIT signaling via PLCγ2-PKD2-PI4KIIIβ activation in gastrointestinal stromal tumor cells. Cell Rep 2023; 42:113035. [PMID: 37616163 DOI: 10.1016/j.celrep.2023.113035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Revised: 06/19/2023] [Accepted: 08/11/2023] [Indexed: 08/25/2023] Open
Abstract
Most gastrointestinal stromal tumors (GISTs) develop due to gain-of-function mutations in the tyrosine kinase gene, KIT. We recently showed that mutant KIT mislocalizes to the Golgi area and initiates uncontrolled signaling. However, the molecular mechanisms underlying its Golgi retention remain unknown. Here, we show that protein kinase D2 (PKD2) is activated by the mutant, which causes Golgi retention of KIT. In PKD2-inhibited cells, KIT migrates from the Golgi region to lysosomes and subsequently undergoes degradation. Importantly, delocalized KIT cannot trigger downstream activation. In the Golgi/trans-Golgi network (TGN), KIT activates the PKD2-phosphatidylinositol 4-kinase IIIβ (PKD2-PI4KIIIβ) pathway through phospholipase Cγ2 (PLCγ2) to generate a PI4P-rich membrane domain, where the AP1-GGA1 complex is aberrantly recruited. Disruption of any factors in this cascade results in the release of KIT from the Golgi/TGN. Our findings show the molecular mechanisms underlying KIT mislocalization and provide evidence for a strategy for inhibition of oncogenic signaling.
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Affiliation(s)
- Yuuki Obata
- Laboratory of Intracellular Traffic & Oncology, National Cancer Center Research Institute, Tsukiji, Chuo-ku, Tokyo 104-0045, Japan.
| | - Kazuo Kurokawa
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced Photonics, Wako, Saitama 351-0198, Japan
| | - Takuro Tojima
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced Photonics, Wako, Saitama 351-0198, Japan
| | - Miyuki Natsume
- Laboratory of Intracellular Traffic & Oncology, National Cancer Center Research Institute, Tsukiji, Chuo-ku, Tokyo 104-0045, Japan; Department of Applied Chemistry, Tokyo University of Science, Shinjuku-ku, Tokyo 162-8601, Japan
| | - Isamu Shiina
- Department of Applied Chemistry, Tokyo University of Science, Shinjuku-ku, Tokyo 162-8601, Japan
| | - Tsuyoshi Takahashi
- Department of Gastroenterological Surgery, Graduate School of Medicine, Osaka University, Suita, Osaka 565-0871, Japan
| | - Ryo Abe
- Tokyo University of Science, Noda, Chiba 278-8510, Japan
| | - Akihiko Nakano
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced Photonics, Wako, Saitama 351-0198, Japan
| | - Toshirou Nishida
- National Cancer Center Hospital, Tsukiji, Chuo-ku, Tokyo 104-0045, Japan; Laboratory of Nuclear Transport Dynamics, National Institutes of Biomedical Innovation, Health and Nutrition, Ibaraki, Osaka 567-0085, Japan
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5
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Hart M, Conrad J, Barrett E, Legg K, Ivey G, Lee PHU, Yung YC, Shim JW. X-linked hydrocephalus genes: Their proximity to telomeres and high A + T content compared to Parkinson's disease. Exp Neurol 2023; 366:114433. [PMID: 37156332 PMCID: PMC10330542 DOI: 10.1016/j.expneurol.2023.114433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 04/15/2023] [Accepted: 05/05/2023] [Indexed: 05/10/2023]
Abstract
Proximity to telomeres (i) and high adenine and thymine (A + T) content (ii) are two factors associated with high mutation rates in human chromosomes. We have previously shown that >100 human genes when mutated to cause congenital hydrocephalus (CH) meet either factor (i) or (ii) at 91% matching, while two factors are poorly satisfied in human genes associated with familial Parkinson's disease (fPD) at 59%. Using the sets of mouse, rat, and human chromosomes, we found that 7 genes associated with CH were located on the X chromosome of mice, rats, and humans. However, genes associated with fPD were in different autosomes depending on species. While the contribution of proximity to telomeres in the autosome was comparable in CH and fPD, high A + T content played a pivotal contribution in X-linked CH (43% in all three species) than in fPD (6% in rodents or 13% in humans). Low A + T content found in fPD cases suggests that PARK family genes harbor roughly 3 times higher chances of methylations in CpG sites or epigenetic changes than X-linked genes.
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Affiliation(s)
- Madeline Hart
- Department of Biomedical Engineering, Marshall University, Huntington, WV, United States
| | - Joshua Conrad
- Department of Biomedical Engineering, Marshall University, Huntington, WV, United States
| | - Emma Barrett
- Department of Biomedical Engineering, Marshall University, Huntington, WV, United States
| | - Kaitlyn Legg
- Department of Biomedical Engineering, Marshall University, Huntington, WV, United States
| | - Gabrielle Ivey
- Department of Biomedical Engineering, Marshall University, Huntington, WV, United States
| | - Peter H U Lee
- Department of Cardiothoracic Surgery, Southcoast Health, Fall River, MA, United States; Department of Pathology and Laboratory Medicine, Brown University, Providence, RI, United States
| | - Yun C Yung
- Department of Neuroscience, The Scintillon Research Institute, San Diego, CA, United States
| | - Joon W Shim
- Department of Biomedical Engineering, Marshall University, Huntington, WV, United States.
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6
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Mignani L, Facchinello N, Varinelli M, Massardi E, Tiso N, Ravelli C, Mitola S, Schu P, Monti E, Finazzi D, Borsani G, Zizioli D. Deficiency of AP1 Complex Ap1g1 in Zebrafish Model Led to Perturbation of Neurodevelopment, Female and Male Fertility; New Insight to Understand Adaptinopathies. Int J Mol Sci 2023; 24:ijms24087108. [PMID: 37108275 PMCID: PMC10138411 DOI: 10.3390/ijms24087108] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2023] [Revised: 04/03/2023] [Accepted: 04/03/2023] [Indexed: 04/29/2023] Open
Abstract
In vertebrates, two homologous heterotetrameric AP1 complexes regulate the intracellular protein sorting via vesicles. AP-1 complexes are ubiquitously expressed and are composed of four different subunits: γ, β1, μ1 and σ1. Two different complexes are present in eukaryotic cells, AP1G1 (contains γ1 subunit) and AP1G2 (contains γ2 subunit); both are indispensable for development. One additional tissue-specific isoform exists for μ1A, the polarized epithelial cells specific to μ1B; two additional tissue-specific isoforms exist for σ1A: σ1B and σ1C. Both AP1 complexes fulfil specific functions at the trans-Golgi network and endosomes. The use of different animal models demonstrated their crucial role in the development of multicellular organisms and the specification of neuronal and epithelial cells. Ap1g1 (γ1) knockout mice cease development at the blastocyst stage, while Ap1m1 (μ1A) knockouts cease during mid-organogenesis. A growing number of human diseases have been associated with mutations in genes encoding for the subunits of adaptor protein complexes. Recently, a new class of neurocutaneous and neurometabolic disorders affecting intracellular vesicular traffic have been referred to as adaptinopathies. To better understand the functional role of AP1G1 in adaptinopathies, we generated a zebrafish ap1g1 knockout using CRISPR/Cas9 genome editing. Zebrafish ap1g1 knockout embryos cease their development at the blastula stage. Interestingly, heterozygous females and males have reduced fertility and showed morphological alterations in the brain, gonads and intestinal epithelium. An analysis of mRNA profiles of different marker proteins and altered tissue morphologies revealed dysregulated cadherin-mediated cell adhesion. These data demonstrate that the zebrafish model organism enables us to study the molecular details of adaptinopathies and thus also develop treatment strategies.
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Affiliation(s)
- Luca Mignani
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa, 11, 25123 Brescia, Italy
| | - Nicola Facchinello
- Neuroscience Institute, Italian Research Council (CNR), 35131 Padova, Italy
| | - Marco Varinelli
- Istituto di Ricerche Farmacologiche Mario Negri IRCCS, 24126 Bergamo, Italy
| | - Elena Massardi
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa, 11, 25123 Brescia, Italy
| | - Natascia Tiso
- Department of Biology, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy
| | - Cosetta Ravelli
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa, 11, 25123 Brescia, Italy
| | - Stefania Mitola
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa, 11, 25123 Brescia, Italy
- CN3 "Sviluppo di Terapia Genica e Farmaci con Tecnologia ad RNA", 25123 Brescia, Italy
| | - Peter Schu
- Department of Cellular Biochemistry, University Medical Center, Georg-August University, Humboldtallee 23, 37073 Gottingen, Germany
| | - Eugenio Monti
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa, 11, 25123 Brescia, Italy
| | - Dario Finazzi
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa, 11, 25123 Brescia, Italy
- Clinical Chemistry Laboratory, ASST Spedali Civili di Brescia, 25123 Brescia, Italy
| | - Giuseppe Borsani
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa, 11, 25123 Brescia, Italy
| | - Daniela Zizioli
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa, 11, 25123 Brescia, Italy
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7
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Duy PQ, Rakic P, Alper SL, Robert SM, Kundishora AJ, Butler WE, Walsh CA, Sestan N, Geschwind DH, Jin SC, Kahle KT. A neural stem cell paradigm of pediatric hydrocephalus. Cereb Cortex 2023; 33:4262-4279. [PMID: 36097331 PMCID: PMC10110448 DOI: 10.1093/cercor/bhac341] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Revised: 07/12/2022] [Accepted: 08/02/2022] [Indexed: 12/25/2022] Open
Abstract
Pediatric hydrocephalus, the leading reason for brain surgery in children, is characterized by enlargement of the cerebral ventricles classically attributed to cerebrospinal fluid (CSF) overaccumulation. Neurosurgical shunting to reduce CSF volume is the default treatment that intends to reinstate normal CSF homeostasis, yet neurodevelopmental disability often persists in hydrocephalic children despite optimal surgical management. Here, we discuss recent human genetic and animal model studies that are shifting the view of pediatric hydrocephalus from an impaired fluid plumbing model to a new paradigm of dysregulated neural stem cell (NSC) fate. NSCs are neuroprogenitor cells that comprise the germinal neuroepithelium lining the prenatal brain ventricles. We propose that heterogenous defects in the development of these cells converge to disrupt cerebrocortical morphogenesis, leading to abnormal brain-CSF biomechanical interactions that facilitate passive pooling of CSF and secondary ventricular distention. A significant subset of pediatric hydrocephalus may thus in fact be due to a developmental brain malformation leading to secondary enlargement of the ventricles rather than a primary defect of CSF circulation. If hydrocephalus is indeed a neuroradiographic presentation of an inborn brain defect, it suggests the need to focus on optimizing neurodevelopment, rather than CSF diversion, as the primary treatment strategy for these children.
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Affiliation(s)
- Phan Q Duy
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT 06510, USA
- Medical Scientist Training Program, Yale University School of Medicine, New Haven, CT 06510, USA
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Pasko Rakic
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Seth L Alper
- Division of Nephrology and Vascular Biology Research Center, Beth Israel Deaconess Medical Center and Department of Medicine, Harvard Medical School, Boston, MA 02215, USA
| | - Stephanie M Robert
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Adam J Kundishora
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT 06510, USA
| | - William E Butler
- Department of Neurosurgery, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Christopher A Walsh
- Division of Genetics and Genomics, Manton Center for Orphan Disease Research, Department of Pediatrics, and Howard Hughes Medical Institute, Boston Children’s Hospital, Boston, MA 02115, USA
- Departments of Pediatrics and Neurology, Harvard Medical School, Boston, MA 02115, USA
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Nenad Sestan
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT 06510, USA
| | - Daniel H Geschwind
- Department of Human Genetics, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Sheng Chih Jin
- Department of Genetics, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Kristopher T Kahle
- Department of Neurosurgery, Massachusetts General Hospital, Boston, MA 02114, USA
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
- Harvard Center for Hydrocephalus and Neurodevelopmental Disorders, Massachusetts General Hospital, Boston, MA 02114, USA
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Zhu D, Wang M, Xu Y, Zhang J, Yang F, Yang Z. Identification of a 5 bp duplicate in the AP1S2 gene of an individual with X-linked intellectual disability. Neurogenetics 2022; 23:179-185. [DOI: 10.1007/s10048-022-00691-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2021] [Accepted: 03/25/2022] [Indexed: 11/28/2022]
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9
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Duncan MC. New directions for the clathrin adaptor AP-1 in cell biology and human disease. Curr Opin Cell Biol 2022; 76:102079. [DOI: 10.1016/j.ceb.2022.102079] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 03/02/2022] [Accepted: 03/03/2022] [Indexed: 11/03/2022]
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10
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Mechanisms regulating the sorting of soluble lysosomal proteins. Biosci Rep 2022; 42:231123. [PMID: 35394021 PMCID: PMC9109462 DOI: 10.1042/bsr20211856] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 04/05/2022] [Accepted: 04/07/2022] [Indexed: 11/17/2022] Open
Abstract
Lysosomes are key regulators of many fundamental cellular processes such as metabolism, autophagy, immune response, cell signalling and plasma membrane repair. These highly dynamic organelles are composed of various membrane and soluble proteins, which are essential for their proper functioning. The soluble proteins include numerous proteases, glycosidases and other hydrolases, along with activators, required for catabolism. The correct sorting of soluble lysosomal proteins is crucial to ensure the proper functioning of lysosomes and is achieved through the coordinated effort of many sorting receptors, resident ER and Golgi proteins, and several cytosolic components. Mutations in a number of proteins involved in sorting soluble proteins to lysosomes result in human disease. These can range from rare diseases such as lysosome storage disorders, to more prevalent ones, such as Alzheimer’s disease, Parkinson’s disease and others, including rare neurodegenerative diseases that affect children. In this review, we discuss the mechanisms that regulate the sorting of soluble proteins to lysosomes and highlight the effects of mutations in this pathway that cause human disease. More precisely, we will review the route taken by soluble lysosomal proteins from their translation into the ER, their maturation along the Golgi apparatus, and sorting at the trans-Golgi network. We will also highlight the effects of mutations in this pathway that cause human disease.
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11
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Li J, Zhang X, Guo J, Yu C, Yang J. Molecular Mechanisms and Risk Factors for the Pathogenesis of Hydrocephalus. Front Genet 2022; 12:777926. [PMID: 35047005 PMCID: PMC8762052 DOI: 10.3389/fgene.2021.777926] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Accepted: 12/03/2021] [Indexed: 12/22/2022] Open
Abstract
Hydrocephalus is a neurological condition due to the aberrant circulation and/or obstruction of cerebrospinal fluid (CSF) flow with consequent enlargement of cerebral ventricular cavities. However, it is noticed that a lot of patients may still go through symptomatic progression despite standard shunting procedures, suggesting that hydrocephalus is far more complicated than a simple CSF circulative/obstructive disorder. Growing evidence indicates that genetic factors play a fundamental role in the pathogenesis of some hydrocephalus. Although the genetic research of hydrocephalus in humans is limited, many genetic loci of hydrocephalus have been defined in animal models. In general, the molecular abnormalities involved in the pathogenesis of hydrocephalus include brain development and ependymal cell dysfunction, apoptosis, inflammation, free radical generation, blood flow, and cerebral metabolism. Moreover, recent studies have indicated that the molecular abnormalities relevant to aberrant cerebral glymphatic drainage turn into an attractive subject in the CSF circulation disorder. Furthermore, the prevalent risk factors could facilitate the development of hydrocephalus. In this review, we elicited some possible fundamental molecular mechanisms and facilitating risk factors involved in the pathogenesis of hydrocephalus, and aimed to widen the diagnosis and therapeutic strategies for hydrocephalus management. Such knowledge could be used to improve patient care in different ways, such as early precise diagnosis and effective therapeutic regimens.
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Affiliation(s)
- Jingwen Li
- Department of Neurosurgery, Xiang'an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
| | - Xinjie Zhang
- Department of Neurosurgery, Tianjin Medical University General Hospital, Tianjin, China
| | - Jian Guo
- Department of Neurosurgery, Xiang'an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
| | - Chen Yu
- Department of Neurosurgery, Xiang'an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
| | - Jun Yang
- Department of Neurosurgery, Xiang'an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, China
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12
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Kundishora AJ, Singh AK, Allington G, Duy PQ, Ryou J, Alper SL, Jin SC, Kahle KT. Genomics of human congenital hydrocephalus. Childs Nerv Syst 2021; 37:3325-3340. [PMID: 34232380 DOI: 10.1007/s00381-021-05230-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 05/24/2021] [Indexed: 12/12/2022]
Abstract
Congenital hydrocephalus (CH), characterized by enlarged brain ventricles, is considered a disease of pathological cerebrospinal fluid (CSF) accumulation and, therefore, treated largely by neurosurgical CSF diversion. The persistence of ventriculomegaly and poor neurodevelopmental outcomes in some post-surgical patients highlights our limited knowledge of disease mechanisms. Recent whole-exome sequencing (WES) studies have shown that rare, damaging de novo and inherited mutations with large effect contribute to ~ 25% of sporadic CH. Interestingly, multiple CH genes are key regulators of neural stem cell growth and differentiation and converge in human transcriptional networks and cell types pertinent to fetal neurogliogenesis. These data implicate genetic disruption of early brain development as the primary pathomechanism in a substantial minority of patients with sporadic CH, shedding new light on human brain development and the pathogenesis of hydrocephalus. These data further suggest WES as a clinical tool with potential to re-classify CH according to a molecular nomenclature of increased precision and utility for genetic counseling, outcome prognostication, and treatment stratification.
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Affiliation(s)
- Adam J Kundishora
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT, USA
| | - Amrita K Singh
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT, USA
| | - Garrett Allington
- Department of Pathology, Yale University School of Medicine, New Haven, CT, USA
| | - Phan Q Duy
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT, USA
| | - Jian Ryou
- Department of Genetics, Washington University School of Medicine, St Louis, MO, USA
| | - Seth L Alper
- Division of Nephrology and Center for Vascular Biology Research, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Sheng Chih Jin
- Department of Genetics, Washington University School of Medicine, St Louis, MO, USA
| | - Kristopher T Kahle
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT, USA.
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13
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Field MJ, Kumar R, Hackett A, Kayumi S, Shoubridge CA, Ewans LJ, Ivancevic AM, Dudding-Byth T, Carroll R, Kroes T, Gardner AE, Sullivan P, Ha TT, Schwartz CE, Cowley MJ, Dinger ME, Palmer EE, Christie L, Shaw M, Roscioli T, Gecz J, Corbett MA. Different types of disease-causing noncoding variants revealed by genomic and gene expression analyses in families with X-linked intellectual disability. Hum Mutat 2021; 42:835-847. [PMID: 33847015 DOI: 10.1002/humu.24207] [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: 07/05/2020] [Revised: 03/19/2021] [Accepted: 04/08/2021] [Indexed: 11/06/2022]
Abstract
The pioneering discovery research of X-linked intellectual disability (XLID) genes has benefitted thousands of individuals worldwide; however, approximately 30% of XLID families still remain unresolved. We postulated that noncoding variants that affect gene regulation or splicing may account for the lack of a genetic diagnosis in some cases. Detecting pathogenic, gene-regulatory variants with the same sensitivity and specificity as structural and coding variants is a major challenge for Mendelian disorders. Here, we describe three pedigrees with suggestive XLID where distinctive phenotypes associated with known genes guided the identification of three different noncoding variants. We used comprehensive structural, single-nucleotide, and repeat expansion analyses of genome sequencing. RNA-Seq from patient-derived cell lines, reverse-transcription polymerase chain reactions, Western blots, and reporter gene assays were used to confirm the functional effect of three fundamentally different classes of pathogenic noncoding variants: a retrotransposon insertion, a novel intronic splice donor, and a canonical splice variant of an untranslated exon. In one family, we excluded a rare coding variant in ARX, a known XLID gene, in favor of a regulatory noncoding variant in OFD1 that correlated with the clinical phenotype. Our results underscore the value of genomic research on unresolved XLID families to aid novel, pathogenic noncoding variant discovery.
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Affiliation(s)
- Michael J Field
- NSW Genetics of Learning Disability Service, Newcastle, New South Wales, Australia
| | - Raman Kumar
- Adelaide Medical School and Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia
| | - Anna Hackett
- NSW Genetics of Learning Disability Service, Newcastle, New South Wales, Australia.,School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, New South Wales, Australia
| | - Sayaka Kayumi
- Adelaide Medical School and Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia
| | - Cheryl A Shoubridge
- Adelaide Medical School and Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia
| | - Lisa J Ewans
- St Vincent's Clinical School, University of New South Wales, Darlinghurst, Australia.,Kinghorn Centre for Clinical Genomics, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
| | - Atma M Ivancevic
- Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, Colorado, USA
| | - Tracy Dudding-Byth
- NSW Genetics of Learning Disability Service, Newcastle, New South Wales, Australia.,School of Biomedical Sciences and Pharmacy, University of Newcastle, Newcastle, New South Wales, Australia
| | - Renée Carroll
- Adelaide Medical School and Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia
| | - Thessa Kroes
- Adelaide Medical School and Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia
| | - Alison E Gardner
- Adelaide Medical School and Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia
| | - Patricia Sullivan
- Children's Cancer Institute, University of New South Wales, Kensington, New South Wales, Australia
| | - Thuong T Ha
- Molecular Pathology Department, Centre for Cancer Biology, SA Pathology, Adelaide, South Australia, Australia
| | | | - Mark J Cowley
- NSW Genetics of Learning Disability Service, Newcastle, New South Wales, Australia.,Kinghorn Centre for Clinical Genomics, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia.,Children's Cancer Institute, University of New South Wales, Kensington, New South Wales, Australia
| | - Marcel E Dinger
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Kensington, New South Wales, Australia
| | - Elizabeth E Palmer
- NSW Genetics of Learning Disability Service, Newcastle, New South Wales, Australia.,School of Women's and Children's Health, University of New South Wales, Kensington, Sydney, New South Wales, Australia
| | - Louise Christie
- NSW Genetics of Learning Disability Service, Newcastle, New South Wales, Australia
| | - Marie Shaw
- Adelaide Medical School and Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia
| | - Tony Roscioli
- NeuRA, University of New South Wales, Sydney, New South Wales, Australia.,Centre for Clinical Genetics, Sydney Children's Hospital, Randwick, Sydney, New South Wales, Australia
| | - Jozef Gecz
- Adelaide Medical School and Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia.,South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
| | - Mark A Corbett
- Adelaide Medical School and Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia
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14
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John A, Ng-Cordell E, Hanna N, Brkic D, Baker K. The neurodevelopmental spectrum of synaptic vesicle cycling disorders. J Neurochem 2021; 157:208-228. [PMID: 32738165 DOI: 10.1111/jnc.15135] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 07/20/2020] [Accepted: 07/21/2020] [Indexed: 12/11/2022]
Abstract
In this review, we describe and discuss neurodevelopmental phenotypes arising from rare, high penetrance genomic variants which directly influence synaptic vesicle cycling (SVC disorders). Pathogenic variants in each SVC disorder gene lead to disturbance of at least one SVC subprocess, namely vesicle trafficking (e.g. KIF1A and GDI1), clustering (e.g. TRIO, NRXN1 and SYN1), docking and priming (e.g. STXBP1), fusion (e.g. SYT1 and PRRT2) or re-uptake (e.g. DNM1, AP1S2 and TBC1D24). We observe that SVC disorders share a common set of neurological symptoms (movement disorders, epilepsies), cognitive impairments (developmental delay, intellectual disabilities, cerebral visual impairment) and mental health difficulties (autism, ADHD, psychiatric symptoms). On the other hand, there is notable phenotypic variation between and within disorders, which may reflect selective disruption to SVC subprocesses, spatiotemporal and cell-specific gene expression profiles, mutation-specific effects, or modifying factors. Understanding the common cellular and systems mechanisms underlying neurodevelopmental phenotypes in SVC disorders, and the factors responsible for variation in clinical presentations and outcomes, may translate to personalized clinical management and improved quality of life for patients and families.
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Affiliation(s)
- Abinayah John
- MRC Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, UK
| | - Elise Ng-Cordell
- MRC Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, UK
| | - Nancy Hanna
- MRC Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, UK
| | - Diandra Brkic
- MRC Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, UK
| | - Kate Baker
- MRC Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, UK
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15
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Jacquemin V, Antoine M, Duerinckx S, Massart A, Desir J, Perazzolo C, Cassart M, Thomas D, Segers V, Lecomte S, Abramowicz M, Pirson I. TrkA mediates effect of novel KIDINS220 mutation in human brain ventriculomegaly. Hum Mol Genet 2020; 29:3757-3764. [PMID: 33205811 DOI: 10.1093/hmg/ddaa245] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 11/09/2020] [Accepted: 11/10/2020] [Indexed: 12/22/2022] Open
Abstract
Congenital hydrocephalus is a potentially devastating, highly heterogeneous condition whose genetic subset remains incompletely known. We here report a consanguineous family where three fetuses presented with brain ventriculomegaly and limb contractures and shared a very rare homozygous variant of KIDINS220, consisting of an in-frame deletion of three amino acids adjacent to the fourth transmembrane domain. Fetal brain imaging and autopsy showed major ventriculomegaly, reduced brain mass, and with no histomorphologic abnormalities. We demonstrate that the binding of KIDINS220 to TrkA is diminished by the deletion mutation. This family is the second that associates a KIDINS220 genetic variant with human ventriculomegaly and limb contractures, validating causality of the gene and indicating TrkA as a likely mediator of the phenotype.
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Affiliation(s)
| | - Mathieu Antoine
- IRIBHM, Université Libre de Bruxelles, 1070 Brussels, Belgium
| | - Sarah Duerinckx
- IRIBHM, Université Libre de Bruxelles, 1070 Brussels, Belgium.,Neurology Department, Hôpital Erasme, Université Libre de Bruxelles, 1070 Brussels, Belgium
| | - Annick Massart
- IRIBHM, Université Libre de Bruxelles, 1070 Brussels, Belgium.,Department of Nephrology, Hôpital Universitaire d'Anvers, 2650 Edegem, Belgium
| | - Julie Desir
- Human Genetics Center, Institute of Pathology and Genetics, 6041 Charleroi, Belgium
| | | | - Marie Cassart
- Department of Gynecology and Obstetrics, Hôpitaux Iris Sud, 1050 Brussels, Belgium
| | - Dominique Thomas
- Department of Gynecology and Obstetrics, Hôpitaux Iris Sud, 1050 Brussels, Belgium
| | - Valérie Segers
- Department of Anatomopathology, CHU Brugmann, 1020 Brussels, Belgium
| | - Sophie Lecomte
- Department of Anatomopathology, CHU Brugmann, 1020 Brussels, Belgium
| | - Marc Abramowicz
- IRIBHM, Université Libre de Bruxelles, 1070 Brussels, Belgium.,Department of Genetic Medicine and Development, Faculty of Medicine, University of Geneva, 1211 Geneva, Switzerland
| | - Isabelle Pirson
- IRIBHM, Université Libre de Bruxelles, 1070 Brussels, Belgium
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16
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Bonnycastle K, Davenport EC, Cousin MA. Presynaptic dysfunction in neurodevelopmental disorders: Insights from the synaptic vesicle life cycle. J Neurochem 2020; 157:179-207. [PMID: 32378740 DOI: 10.1111/jnc.15035] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 04/14/2020] [Accepted: 04/22/2020] [Indexed: 12/11/2022]
Abstract
The activity-dependent fusion, retrieval and recycling of synaptic vesicles is essential for the maintenance of neurotransmission. Until relatively recently it was believed that most mutations in genes that were essential for this process would be incompatible with life, because of this fundamental role. However, an ever-expanding number of mutations in this very cohort of genes are being identified in individuals with neurodevelopmental disorders, including autism, intellectual disability and epilepsy. This article will summarize the current state of knowledge linking mutations in presynaptic genes to neurodevelopmental disorders by sequentially covering the various stages of the synaptic vesicle life cycle. It will also discuss how perturbations of specific stages within this recycling process could translate into human disease. Finally, it will also provide perspectives on the potential for future therapy that are targeted to presynaptic function.
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Affiliation(s)
- Katherine Bonnycastle
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK.,Muir Maxwell Epilepsy Centre, University of Edinburgh, Edinburgh, UK.,Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, UK
| | - Elizabeth C Davenport
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK.,Muir Maxwell Epilepsy Centre, University of Edinburgh, Edinburgh, UK.,Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, UK
| | - Michael A Cousin
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, UK.,Muir Maxwell Epilepsy Centre, University of Edinburgh, Edinburgh, UK.,Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh, UK
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17
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Faergeman SL, Evans H, Attfield KE, Desel C, Kuttikkatte SB, Sommerlund M, Jensen LT, Frokiaer J, Friese MA, Matthews PM, Luchtenborg C, Brügger B, Oturai AB, Dendrou CA, Fugger L. A novel neurodegenerative spectrum disorder in patients with MLKL deficiency. Cell Death Dis 2020; 11:303. [PMID: 32358523 PMCID: PMC7195448 DOI: 10.1038/s41419-020-2494-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 04/06/2020] [Accepted: 04/07/2020] [Indexed: 12/14/2022]
Abstract
Mixed lineage kinase domain-like (MLKL) is the main executor of necroptosis, an inflammatory form of programmed cell death. Necroptosis is implicated in combating infections, but also in contributing to numerous other clinical conditions, including cardiovascular diseases and neurodegenerative disorders. Inhibition of necroptosis is therefore of therapeutic interest. Here we report two siblings both of whom over the course of 35 years developed a similar progressive, neurodegenerative spectrum disorder characterized by paresis, ataxia and dysarthria. Magnetic resonance imaging of their central nervous system (CNS) revealed severe global cerebral volume loss and atrophy of the cerebellum and brainstem. These brothers are homozygous for a rare haplotype identified by whole genome sequencing carrying a frameshift variant in MLKL, as well as an in-frame deletion of one amino acid in the adjacent fatty acid 2-hydroxylase (FA2H) gene. Functional studies of patient-derived primary cells demonstrated that the variant in MLKL leads to a deficiency of MLKL protein resulting in impairment of necroptosis. Conversely, shotgun lipidomic analysis of the variant in FA2H shows no impact on either the abundance or the enzymatic activity of the encoded hydroxylase. To our knowledge, this is the first report of complete necroptosis deficiency in humans. The findings may suggest that impaired necroptosis is a novel mechanism of neurodegeneration, promoting a disorder that shares some clinical features with primary progressive multiple sclerosis (PPMS) and other neurodegenerative diseases. Importantly, the necroptotic deficiency does not cause symptoms outside the nervous system, nor does it confer susceptibility to infections. Given the current interest in pharmacological inhibition of necroptosis by targeting MLKL and its associated pathways, this strategy should be developed with caution, with careful consideration of the possible development of adverse neurological effects.
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Affiliation(s)
- Soren L Faergeman
- Oxford Centre for Neuroinflammation, Nuffield Department of Clinical Neurosciences, Division of Clinical Neurology, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK
- Department of Clinical Medicine, Aarhus University Hospital, Aarhus, DK-8200, Denmark
| | - Hayley Evans
- Oxford Centre for Neuroinflammation, Nuffield Department of Clinical Neurosciences, Division of Clinical Neurology, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK
| | - Kathrine E Attfield
- Oxford Centre for Neuroinflammation, Nuffield Department of Clinical Neurosciences, Division of Clinical Neurology, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK
| | - Christiane Desel
- Oxford Centre for Neuroinflammation, Nuffield Department of Clinical Neurosciences, Division of Clinical Neurology, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK
| | - Subita Balaram Kuttikkatte
- Oxford Centre for Neuroinflammation, Nuffield Department of Clinical Neurosciences, Division of Clinical Neurology, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK
| | - Mette Sommerlund
- Department of Clinical Medicine, Aarhus University Hospital, Aarhus, DK-8200, Denmark
| | - Lise Torp Jensen
- Department of Clinical Medicine, Aarhus University Hospital, Aarhus, DK-8200, Denmark
| | - Jorgen Frokiaer
- Department of Clinical Medicine, Aarhus University Hospital, Aarhus, DK-8200, Denmark
| | - Manuel A Friese
- Institute of Neuroimmunology and Multiple Sclerosis, University Medical Center Hamburg-Eppendorf, Hamburg, 20246, Germany
| | - Paul M Matthews
- Division of Brain Sciences, Department of Medicine, UK Dementia Research Institute, Imperial College London, London, SW7 2AZ, UK
| | | | - Britta Brügger
- Heidelberg University Biochemistry Center (BZH), Heidelberg, D-69120, Germany
| | - Annette Bang Oturai
- Danish Multiple Sclerosis Center, Department of Neurology, Copenhagen University Hospital, Copenhagen, 2100, Denmark
| | - Calliope A Dendrou
- Wellcome Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, UK
| | - Lars Fugger
- Oxford Centre for Neuroinflammation, Nuffield Department of Clinical Neurosciences, Division of Clinical Neurology, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK.
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, University of Oxford, Oxford, OX3 9DS, UK.
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18
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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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19
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Recessive Mutations in AP1B1 Cause Ichthyosis, Deafness, and Photophobia. Am J Hum Genet 2019; 105:1023-1029. [PMID: 31630788 DOI: 10.1016/j.ajhg.2019.09.021] [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: 07/10/2019] [Accepted: 09/17/2019] [Indexed: 12/13/2022] Open
Abstract
We describe unrelated individuals with ichthyosis, failure to thrive, thrombocytopenia, photophobia, and progressive hearing loss. Each have bi-allelic mutations in AP1B1, the gene encoding the β subunit of heterotetrameric adaptor protein 1 (AP-1) complexes, which mediate endomembrane polarization, sorting, and transport. In affected keratinocytes the AP-1 β subunit is lost, and the γ subunit is greatly reduced, demonstrating destabilization of the AP-1 complex. Affected cells and tissue contain an abundance of abnormal vesicles and show hyperproliferation, abnormal epidermal differentiation, and derangement of intercellular junction proteins. Transduction of affected cells with wild-type AP1B1 rescues the vesicular phenotype, conclusively establishing that loss of AP1B1 function causes this disorder.
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20
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Sanger A, Hirst J, Davies AK, Robinson MS. Adaptor protein complexes and disease at a glance. J Cell Sci 2019; 132:132/20/jcs222992. [PMID: 31636158 DOI: 10.1242/jcs.222992] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Adaptor protein (AP) complexes are heterotetramers that select cargo for inclusion into transport vesicles. Five AP complexes (AP-1 to AP-5) have been described, each with a distinct localisation and function. Furthermore, patients with a range of disorders, particularly involving the nervous system, have now been identified with mutations in each of the AP complexes. In many cases this has been correlated with aberrantly localised membrane proteins. In this Cell Science at a Glance article and the accompanying poster, we summarize what is known about the five AP complexes and discuss how this helps to explain the clinical features of the different genetic disorders.
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Affiliation(s)
- Anneri Sanger
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, UK
| | - Jennifer Hirst
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, UK
| | - Alexandra K Davies
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, UK
| | - Margaret S Robinson
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, UK
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21
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Shin J, Choi JH, Jung S, Jeong S, Oh J, Yoon DY, Rhee MH, Ahn J, Kim SH, Oh JW. MUDENG Expression Profiling in Cohorts and Brain Tumor Biospecimens to Evaluate Its Role in Cancer. Front Genet 2019; 10:884. [PMID: 31616474 PMCID: PMC6763691 DOI: 10.3389/fgene.2019.00884] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 08/21/2019] [Indexed: 01/22/2023] Open
Abstract
Mu-2-related death-inducing gene (MUDENG, MuD) has been reported to be involved in the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-associated apoptotic pathway of glioblastoma multiforme (GBM) cells; however, its expression level, interactors, and role in tumors are yet to be discovered. To investigate whether MuD expression correlates with cancer progression, we analyzed The Cancer Genome Atlas (TCGA) database using UALCAN and Gene Expression Profiling Interactive Analysis (GEPIA). Differential expression of MuD was detected in 6 and 10 cancer types, respectively. Validation performed using data from the Gene Expression Omnibus database showed that MuD expression is downregulated in KIRC tumor and correlate with higher chance of survival. Upregulation of MuD expression in GBM tumors was detected through GEPIA and high MuD expression correlated with higher survival in proneural GBM, whereas the opposite was observed in classical GBM subtype. GBM biospecimens analysis shows that MuD protein level was upregulated in three of six specimens, whereas mRNA level remained relatively unaltered. Therefore, MuD may exert differential effects according to subtypes, and/or be subjected to post-translational regulation in GBM. Correlation analysis between GBM cohort database and experiments using GBM cell lines revealed its positive effect on regulation of protein phosphatase 2 regulatory subunit B’Epsilon (PPP2R5E) and son of sevenless homolog 2 (SOS2). STRING database analysis indicated that the components of adaptor protein complexes putatively interacted with MuD but showed no correlation in terms of survival of patients with different GBM subtypes. In summary, we analyzed the expression of MuD in publicly available cancer patient data sets, GBM cell lines, and biospecimens to demonstrate its potential role as a biomarker for cancer prognosis and identified its candidate interacting molecules.
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Affiliation(s)
- Juhyun Shin
- Animal Resources Research Center, Konkuk University, Seoul, South Korea.,Department of Stem Cell and Regenerative Biotechnology, Konkuk University, Seoul, South Korea
| | - Jun-Ha Choi
- Department of Stem Cell and Regenerative Biotechnology, Konkuk University, Seoul, South Korea
| | - Seunghwa Jung
- Department of Stem Cell and Regenerative Biotechnology, Konkuk University, Seoul, South Korea
| | - Somi Jeong
- Department of Stem Cell and Regenerative Biotechnology, Konkuk University, Seoul, South Korea
| | - Jeongheon Oh
- Department of Stem Cell and Regenerative Biotechnology, Konkuk University, Seoul, South Korea
| | - Do-Young Yoon
- Department of Bioscience and Biotechnology, Konkuk Institute of Technology, Konkuk University, Seoul, South Korea
| | - Man Hee Rhee
- Department of Veterinary Medicine, College of Veterinary Medicine, Kyungpook National University, Daegu, South Korea
| | - Jaehong Ahn
- Department of Ophthalmology, Ajou University School of Medicine, Suwon, South Korea
| | - Se-Hyuk Kim
- Department of Neurosurgery, Ajou University School of Medicine, Suwon, South Korea
| | - Jae-Wook Oh
- Animal Resources Research Center, Konkuk University, Seoul, South Korea.,Department of Stem Cell and Regenerative Biotechnology, Konkuk University, Seoul, South Korea
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22
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Jin SC, Furey CG, Zeng X, Allocco A, Nelson‐Williams C, Dong W, Karimy JK, Wang K, Ma S, Delpire E, Kahle KT. SLC12A ion transporter mutations in sporadic and familial human congenital hydrocephalus. Mol Genet Genomic Med 2019; 7:e892. [PMID: 31393094 PMCID: PMC6732308 DOI: 10.1002/mgg3.892] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 06/15/2019] [Accepted: 07/07/2019] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Congenital hydrocephalus (CH) is a highly morbid disease that features enlarged brain ventricles and impaired cerebrospinal fluid homeostasis. Although early linkage or targeted sequencing studies in large multigenerational families have localized several genes for CH, the etiology of most CH cases remains unclear. Recent advances in whole exome sequencing (WES) have identified five new bona fide CH genes, implicating impaired regulation of neural stem cell fate in CH pathogenesis. Nonetheless, in the majority of CH cases, the pathological etiology remains unknown, suggesting more genes await discovery. METHODS WES of family members of a sporadic and familial form of severe L1CAM mutation-negative CH associated with aqueductal stenosis was performed. Rare genetic variants were analyzed, prioritized, and validated. De novo copy number variants (CNVs) were identified using the XHMM algorithm and validated using qPCR. Xenopus oocyte experiments were performed to access mutation impact on protein function and expression. RESULTS A novel inherited protein-damaging mutation (p.Pro605Leu) in SLC12A6, encoding the K+ -Cl- cotransporter KCC3, was identified in both affected members of multiplex kindred CHYD110. p.Pro605 is conserved in KCC3 orthologs and among all human KCC paralogs. The p.Pro605Leu mutation maps to the ion-transporting domain, and significantly reduces KCC3-dependent K+ transport. A novel de novo CNV (deletion) was identified in SLC12A7, encoding the KCC3 paralog and binding partner KCC4, in another family (CHYD130) with sporadic CH. CONCLUSION These findings identify two novel, related genes associated with CH, and implicate genetically encoded impairments in ion transport for the first time in CH pathogenesis.
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Affiliation(s)
- Sheng Chih Jin
- Department of GeneticsYale University School of MedicineNew HavenCTUSA
- Laboratory of Human Genetics and GenomicsThe Rockefeller UniversityNew YorkNYUSA
| | - Charuta G. Furey
- Department of GeneticsYale University School of MedicineNew HavenCTUSA
- Department of NeurosurgeryYale University School of MedicineNew HavenCTUSA
| | - Xue Zeng
- Department of GeneticsYale University School of MedicineNew HavenCTUSA
| | - August Allocco
- Department of NeurosurgeryYale University School of MedicineNew HavenCTUSA
| | | | - Weilai Dong
- Department of GeneticsYale University School of MedicineNew HavenCTUSA
| | - Jason K. Karimy
- Department of NeurosurgeryYale University School of MedicineNew HavenCTUSA
| | - Kevin Wang
- Department of NeurosurgeryYale University School of MedicineNew HavenCTUSA
| | - Shaojie Ma
- Department of GeneticsYale University School of MedicineNew HavenCTUSA
| | - Eric Delpire
- Department of AnesthesiologyVanderbilt University School of MedicineNashvilleTNUSA
| | - Kristopher T. Kahle
- Department of GeneticsYale University School of MedicineNew HavenCTUSA
- Department of NeurosurgeryYale University School of MedicineNew HavenCTUSA
- Department of Cellular & Molecular PhysiologyYale University School of MedicineNew HavenCTUSA
- NIH‐Yale Centers for Mendelian Genomics, Yale School of MedicineNew HavenCTUSA
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23
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Abstract
Protein coats are supramolecular complexes that assemble on the cytosolic face of membranes to promote cargo sorting and transport carrier formation in the endomembrane system of eukaryotic cells. Several types of protein coats have been described, including COPI, COPII, AP-1, AP-2, AP-3, AP-4, AP-5, and retromer, which operate at different stages of the endomembrane system. Defects in these coats impair specific transport pathways, compromising the function and viability of the cells. In humans, mutations in subunits of these coats cause various congenital diseases that are collectively referred to as coatopathies. In this article, we review the fundamental properties of protein coats and the diseases that result from mutation of their constituent subunits.
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Affiliation(s)
- Esteban C Dell'Angelica
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, California 90095, USA
| | - Juan S Bonifacino
- Cell Biology and Neurobiology Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health, Bethesda, Maryland 20892, USA;
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24
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Cargo Sorting at the trans-Golgi Network for Shunting into Specific Transport Routes: Role of Arf Small G Proteins and Adaptor Complexes. Cells 2019; 8:cells8060531. [PMID: 31163688 PMCID: PMC6627992 DOI: 10.3390/cells8060531] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 05/29/2019] [Accepted: 05/30/2019] [Indexed: 01/27/2023] Open
Abstract
The trans-Golgi network (TGN) is responsible for selectively recruiting newly synthesized cargo into transport carriers for delivery to their appropriate destination. In addition, the TGN is responsible for receiving and recycling cargo from endosomes. The membrane organization of the TGN facilitates the sorting of cargoes into distinct populations of transport vesicles. There have been significant advances in defining the molecular mechanism involved in the recognition of membrane cargoes for recruitment into different populations of transport carriers. This machinery includes cargo adaptors of the adaptor protein (AP) complex family, and monomeric Golgi-localized γ ear-containing Arf-binding protein (GGA) family, small G proteins, coat proteins, as well as accessory factors to promote budding and fission of transport vesicles. Here, we review this literature with a particular focus on the transport pathway(s) mediated by the individual cargo adaptors and the cargo motifs recognized by these adaptors. Defects in these cargo adaptors lead to a wide variety of diseases.
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25
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Huo L, Teng Z, Wang H, Liu X. A novel splice site mutation in AP1S2 gene for X-linked mental retardation in a Chinese pedigree and literature review. Brain Behav 2019; 9:e01221. [PMID: 30714330 PMCID: PMC6422709 DOI: 10.1002/brb3.1221] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Revised: 01/08/2019] [Accepted: 01/09/2019] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Pettigrew syndrome (PGS) is a rare X-linked mental retardation that caused by AP1S2 mutation. The pathogenesis of AP1S2 deficiency has remained elusive. The purpose of this study is to give a comprehensive overview of the phenotypic and genetic spectrum of AP1S2 mutations. METHODS This study systematically analyzed clinical features and genetic information of a Chinese family with AP1S2 variation, and reviewed previously reported literatures with the same gene variation. RESULTS We identified a new c.1-1 G>C mutation in AP1S2 gene from a four generation family with seven affected individuals and found the elevated neuron-specific enolase (NSE) in a patient. We summarized the clinical manifestation of 59 patients with AP1S2 mutation. We found that pathogenic point mutations affecting AP1S2 are associated with dysmorphic features and neurodevelopmental problems, which included highly variable mental retardation (MR), delayed in walking, abnormal speech, hypotonia, abnormal brain, abnormal behavior including aggressive behavior, ASD, self-abusive, and abnormal gait. Patients with splice site mutation were more likely to lead to seizures. By contrast, patients with nonsense mutations are more susceptible to microcephaly. CONCLUSION Our findings suggest AP1S2 mutations contribute to a broad spectrum of neurodevelopmental disorders and are important in the etiological spectrum of PGS.
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Affiliation(s)
- Liang Huo
- Department of Pediatric Neurology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Ziteng Teng
- Department of Pediatric Neurology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Hua Wang
- Department of Pediatric Neurology, Shengjing Hospital of China Medical University, Shenyang, China
| | - Xueyan Liu
- Department of Pediatric Neurology, Shengjing Hospital of China Medical University, Shenyang, China
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26
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Guardia CM, De Pace R, Mattera R, Bonifacino JS. Neuronal functions of adaptor complexes involved in protein sorting. Curr Opin Neurobiol 2018; 51:103-110. [PMID: 29558740 DOI: 10.1016/j.conb.2018.02.021] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Revised: 02/16/2018] [Accepted: 02/27/2018] [Indexed: 11/30/2022]
Abstract
Selective transport of transmembrane proteins to different intracellular compartments often involves the recognition of sorting signals in the cytosolic domains of the proteins by components of membrane coats. Some of these coats have as their key components a family of heterotetrameric adaptor protein (AP) complexes named AP-1 through AP-5. AP complexes play important roles in all cells, but their functions are most critical in neurons because of the extreme compartmental complexity of these cells. Accordingly, various diseases caused by mutations in AP subunit genes exhibit a range of neurological abnormalities as their most salient features. In this article, we discuss the properties of the different AP complexes, with a focus on their roles in neuronal physiology and pathology.
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Affiliation(s)
- Carlos M Guardia
- Cell Biology and Neurobiology Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Raffaella De Pace
- Cell Biology and Neurobiology Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Rafael Mattera
- Cell Biology and Neurobiology Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA
| | - Juan S Bonifacino
- Cell Biology and Neurobiology Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
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27
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Abstract
X-linked cerebellar ataxias (XLCA) are an expanding group of genetically heterogeneous and clinically variable conditions characterized by cerebellar dysgenesis (hypoplasia, atrophy, or dysplasia) caused by gene mutations or genomic imbalances on the X chromosome. The neurologic features of XLCA include hypotonia, developmental delay, intellectual disability, ataxia, and other cerebellar signs. Normal cognitive development has also been reported. Cerebellar defects may be isolated or associated with other brain malformations or extraneurologic involvement. More than 20 genes on the X chromosome, mainly encoding for proteins involved in brain development and synaptic function that have been constantly or occasionally associated with a pathologic cerebellar phenotype, and several families with X-linked inheritance have been reported. Given the excess of males with ataxia, this group of conditions is probably underestimated and families of patients with neuroradiologic and clinical evidence of a cerebellar disorder should be counseled for high risk of X-linked inheritance.
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Affiliation(s)
- Ginevra Zanni
- Unit of Neuromuscular and Neurodegenerative Disorders, Bambino Gesu' Children's Research Hospital, Rome, Italy.
| | - Enrico Bertini
- Unit of Neuromuscular and Neurodegenerative Disorders, Bambino Gesu' Children's Research Hospital, Rome, Italy
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28
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Verma R, Ramkumar HL, Zhang K, Granet DB, Hertle RW. X-Linked Idiopathic Infantile Nystagmus (XLIIN): Case Report and Review of Literature. CURRENT OPHTHALMOLOGY REPORTS 2017. [DOI: 10.1007/s40135-017-0139-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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29
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Progida C, Bakke O. Bidirectional traffic between the Golgi and the endosomes - machineries and regulation. J Cell Sci 2016; 129:3971-3982. [PMID: 27802132 DOI: 10.1242/jcs.185702] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The bidirectional transport between the Golgi complex and the endocytic pathway has to be finely regulated in order to ensure the proper delivery of newly synthetized lysosomal enzymes and the return of sorting receptors from degradative compartments. The high complexity of these routes has led to experimental difficulties in properly dissecting and separating the different pathways. As a consequence, several models have been proposed during the past decades. However, recent advances in our understanding of endosomal dynamics have helped to unify these different views. We provide here an overview of the current insights into the transport routes between Golgi and endosomes in mammalian cells. The focus of the Commentary is on the key molecules involved in the trafficking pathways between these intracellular compartments, such as Rab proteins and sorting receptors, and their regulation. A proper understanding of the bidirectional traffic between the Golgi complex and the endolysosomal system is of uttermost importance, as several studies have demonstrated that mutations in the factors involved in these transport pathways result in various pathologies, in particular lysosome-associated diseases and diverse neurological disorders, such as Alzheimer's and Parkinson's disease.
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Affiliation(s)
- Cinzia Progida
- Department of Biosciences, Centre for Immune Regulation, University of Oslo, Oslo, Norway
| | - Oddmund Bakke
- Department of Biosciences, Centre for Immune Regulation, University of Oslo, Oslo, Norway
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30
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Candiello E, Kratzke M, Wenzel D, Cassel D, Schu P. AP-1/σ1A and AP-1/σ1B adaptor-proteins differentially regulate neuronal early endosome maturation via the Rab5/Vps34-pathway. Sci Rep 2016; 6:29950. [PMID: 27411398 PMCID: PMC4944158 DOI: 10.1038/srep29950] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 06/24/2016] [Indexed: 12/26/2022] Open
Abstract
The σ1 subunit of the AP-1 clathrin-coated-vesicle adaptor-protein
complex is expressed as three isoforms. Tissues express σ1A and one of
the σ1B and σ1C isoforms. Brain is the tissue with the
highest σ1A and σ1B expression. σ1B-deficiency
leads to severe mental retardation, accumulation of early endosomes in synapses and
fewer synaptic vesicles, whose recycling is slowed down. AP-1/σ1A and
AP-1/σ1B regulate maturation of these early endosomes into
multivesicular body late endosomes, thereby controlling synaptic vesicle protein
transport into a degradative pathway. σ1A binds ArfGAP1, and with higher
affinity brain-specific ArfGAP1, which bind Rabex-5.
AP-1/σ1A-ArfGAP1-Rabex-5 complex formation leads to more endosomal
Rabex-5 and enhanced, Rab5GTP-stimulated Vps34 PI3-kinase activity,
which is essential for multivesicular body endosome formation. Formation of
AP-1/σ1A-ArfGAP1-Rabex-5 complexes is prevented by σ1B
binding of Rabex-5 and the amount of endosomal Rabex-5 is reduced. AP-1 complexes
differentially regulate endosome maturation and coordinate protein recycling and
degradation, revealing a novel molecular mechanism by which they regulate protein
transport besides their established function in clathrin-coated-vesicle
formation.
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Affiliation(s)
- Ermes Candiello
- Georg-August University Göttingen, Department for Cellular Biochemistry, Humboldtallee 23, D-37073 Göttingen, Germany
| | - Manuel Kratzke
- Georg-August University Göttingen, Department for Cellular Biochemistry, Humboldtallee 23, D-37073 Göttingen, Germany
| | - Dirk Wenzel
- Electron microscopy, Max-Planck-Institut for Biophysical Chemistry, Am Fassberg 11, D-37077 Göttingen, Germany
| | - Dan Cassel
- Israel Institute of Technology, Department Biology, Haifa 32000, Israel
| | - Peter Schu
- Georg-August University Göttingen, Department for Cellular Biochemistry, Humboldtallee 23, D-37073 Göttingen, Germany
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Abstract
Studies of syndromic hydrocephalus have led to the identification of >100 causative genes. Even though this work has illuminated numerous pathways associated with hydrocephalus, it has also highlighted the fact that the genetics underlying this phenotype are more complex than anticipated originally. Mendelian forms of hydrocephalus account for a small fraction of the genetic burden, with clear evidence of background-dependent effects of alleles on penetrance and expressivity of driver mutations in key developmental and homeostatic pathways. Here, we synthesize the currently implicated genes and inheritance paradigms underlying hydrocephalus, grouping causal loci into functional modules that affect discrete, albeit partially overlapping, cellular processes. These in turn have the potential to both inform pathomechanism and assist in the rational molecular classification of a clinically heterogeneous phenotype. Finally, we discuss conceptual methods that can lead to enhanced gene identification and dissection of disease basis, knowledge that will potentially form a foundation for the design of future therapeutics.
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Affiliation(s)
- Maria Kousi
- Center for Human Disease Modeling, Duke University School of Medicine, Durham, North Carolina 27701;
| | - Nicholas Katsanis
- Center for Human Disease Modeling, Duke University School of Medicine, Durham, North Carolina 27701;
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32
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A hypomorphic mutation of the gamma-1 adaptin gene (Ap1g1) causes inner ear, retina, thyroid, and testes abnormalities in mice. Mamm Genome 2016; 27:200-12. [PMID: 27090238 DOI: 10.1007/s00335-016-9632-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 03/24/2016] [Indexed: 10/21/2022]
Abstract
Adaptor protein (AP) complexes function in the intracellular sorting and vesicular transport of membrane proteins. The clathrin-associated AP-1 complex functions at the trans-Golgi network and endosomes, and some forms of this complex are thought to mediate the sorting of proteins in plasma membranes of polarized epithelial cells. A null mutation of the mouse Ap1g1 gene, which encodes the gamma-1 subunit of the AP-1 complex, causes embryonic lethality when homozygous, indicating its critical importance in early development but precluding studies of its possible roles during later stages. Here, we describe our analyses of a new spontaneous mutation of Ap1g1 named "figure eight" (symbol fgt) and show that it is an in-frame deletion of 6 bp, which results in the elimination of two amino acids of the encoded protein. In contrast to Ap1g1 (-/-) null mice, mice homozygous for the recessive fgt mutation are viable with adult survival similar to controls. Although Ap1g1 is ubiquitously expressed, the phenotype of Ap1g1 (fgt) mutant mice is primarily restricted to abnormalities in sensory epithelial cells of the inner ear, pigmented epithelial cells of the retina, follicular epithelial cells of the thyroid gland, and the germinal epithelium of the testis, suggesting that impaired AP-1 sorting and targeting of membrane proteins in these polarized cells may underlie the observed pathologies. Ap1g1 (fgt) mutant mice provide a new animal model to study the in vivo roles of gamma-1 adaptin and the AP-1 complex throughout development and to investigate factors that underlie its associated phenotypic abnormalities.
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33
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Whitfield ST, Burston HE, Bean BDM, Raghuram N, Maldonado-Báez L, Davey M, Wendland B, Conibear E. The alternate AP-1 adaptor subunit Apm2 interacts with the Mil1 regulatory protein and confers differential cargo sorting. Mol Biol Cell 2015; 27:588-98. [PMID: 26658609 PMCID: PMC4751606 DOI: 10.1091/mbc.e15-09-0621] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 12/01/2015] [Indexed: 12/31/2022] Open
Abstract
Adaptor complexes are important for cargo sorting in clathrin-coated vesicles. The µ adaptor subunits Apm1 and Apm2 create functionally distinct versions of the yeast AP-1 complex. A novel regulatory protein is identified that selectively binds Apm2-containing complexes and contributes to their membrane recruitment. Heterotetrameric adaptor protein complexes are important mediators of cargo protein sorting in clathrin-coated vesicles. The cell type–specific expression of alternate μ chains creates distinct forms of AP-1 with altered cargo sorting, but how these subunits confer differential function is unclear. Whereas some studies suggest the μ subunits specify localization to different cellular compartments, others find that the two forms of AP-1 are present in the same vesicle but recognize different cargo. Yeast have two forms of AP-1, which differ only in the μ chain. Here we show that the variant μ chain Apm2 confers distinct cargo-sorting functions. Loss of Apm2, but not of Apm1, increases cell surface levels of the v-SNARE Snc1. However, Apm2 is unable to replace Apm1 in sorting Chs3, which requires a dileucine motif recognized by the γ/σ subunits common to both complexes. Apm2 and Apm1 colocalize at Golgi/early endosomes, suggesting that they do not associate with distinct compartments. We identified a novel, conserved regulatory protein that is required for Apm2-dependent sorting events. Mil1 is a predicted lipase that binds Apm2 but not Apm1 and contributes to its membrane recruitment. Interactions with specific regulatory factors may provide a general mechanism to diversify the functional repertoire of clathrin adaptor complexes.
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Affiliation(s)
- Shawn T Whitfield
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Vancouver, University of British Columbia, Vancouver, BC V5Z 4H4, Canada Department of Biochemistry and Molecular Biology and Department of Medical Genetics, Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Helen E Burston
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Vancouver, University of British Columbia, Vancouver, BC V5Z 4H4, Canada Department of Biochemistry and Molecular Biology and Department of Medical Genetics, Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Björn D M Bean
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Vancouver, University of British Columbia, Vancouver, BC V5Z 4H4, Canada Department of Biochemistry and Molecular Biology and Department of Medical Genetics, Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
| | - Nandini Raghuram
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Vancouver, University of British Columbia, Vancouver, BC V5Z 4H4, Canada
| | | | - Michael Davey
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Vancouver, University of British Columbia, Vancouver, BC V5Z 4H4, Canada
| | - Beverly Wendland
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218-2685
| | - Elizabeth Conibear
- Centre for Molecular Medicine and Therapeutics, Child and Family Research Institute, Vancouver, University of British Columbia, Vancouver, BC V5Z 4H4, Canada Department of Biochemistry and Molecular Biology and Department of Medical Genetics, Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z3, Canada
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34
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Robinson MS. Forty Years of Clathrin-coated Vesicles. Traffic 2015; 16:1210-38. [PMID: 26403691 DOI: 10.1111/tra.12335] [Citation(s) in RCA: 234] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Revised: 09/16/2015] [Accepted: 09/16/2015] [Indexed: 12/11/2022]
Abstract
The purification of coated vesicles and the discovery of clathrin by Barbara Pearse in 1975 was a landmark in cell biology. Over the past 40 years, work from many labs has uncovered the molecular details of clathrin and its associated proteins, including how they assemble into a coated vesicle and how they select cargo. Unexpected connections have been found with signalling, development, neuronal transmission, infection, immunity and genetic disorders. But there are still a number of unanswered questions, including how clathrin-mediated trafficking is regulated and how the machinery evolved.
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Affiliation(s)
- Margaret S Robinson
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
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35
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Hunter JM, Kiefer J, Balak CD, Jooma S, Ahearn ME, Hall JG, Baumbach-Reardon L. Review of X-linked syndromes with arthrogryposis or early contractures-aid to diagnosis and pathway identification. Am J Med Genet A 2015; 167A:931-73. [DOI: 10.1002/ajmg.a.36934] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Accepted: 12/05/2014] [Indexed: 02/03/2023]
Affiliation(s)
- Jesse M. Hunter
- Integrated Functional Cancer Genomics; Translational Genomics Research Institute; Phoenix Arizona
| | - Jeff Kiefer
- Knowledge Mining; Translational Genomics Research Institute; Phoenix Arizona
| | - Christopher D. Balak
- Integrated Functional Cancer Genomics; Translational Genomics Research Institute; Phoenix Arizona
| | - Sonya Jooma
- Integrated Functional Cancer Genomics; Translational Genomics Research Institute; Phoenix Arizona
| | - Mary Ellen Ahearn
- Integrated Functional Cancer Genomics; Translational Genomics Research Institute; Phoenix Arizona
| | - Judith G. Hall
- Departments of Medical Genetics and Pediatrics; University of British Columbia and BC Children's Hospital Vancouver; British Columbia Canada
| | - Lisa Baumbach-Reardon
- Integrated Functional Cancer Genomics; Translational Genomics Research Institute; Phoenix Arizona
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36
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Irimia M, Weatheritt RJ, Ellis JD, Parikshak NN, Gonatopoulos-Pournatzis T, Babor M, Quesnel-Vallières M, Tapial J, Raj B, O'Hanlon D, Barrios-Rodiles M, Sternberg MJE, Cordes SP, Roth FP, Wrana JL, Geschwind DH, Blencowe BJ. A highly conserved program of neuronal microexons is misregulated in autistic brains. Cell 2015; 159:1511-23. [PMID: 25525873 DOI: 10.1016/j.cell.2014.11.035] [Citation(s) in RCA: 416] [Impact Index Per Article: 46.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 10/20/2014] [Accepted: 11/18/2014] [Indexed: 12/16/2022]
Abstract
Alternative splicing (AS) generates vast transcriptomic and proteomic complexity. However, which of the myriad of detected AS events provide important biological functions is not well understood. Here, we define the largest program of functionally coordinated, neural-regulated AS described to date in mammals. Relative to all other types of AS within this program, 3-15 nucleotide "microexons" display the most striking evolutionary conservation and switch-like regulation. These microexons modulate the function of interaction domains of proteins involved in neurogenesis. Most neural microexons are regulated by the neuronal-specific splicing factor nSR100/SRRM4, through its binding to adjacent intronic enhancer motifs. Neural microexons are frequently misregulated in the brains of individuals with autism spectrum disorder, and this misregulation is associated with reduced levels of nSR100. The results thus reveal a highly conserved program of dynamic microexon regulation associated with the remodeling of protein-interaction networks during neurogenesis, the misregulation of which is linked to autism.
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Affiliation(s)
- Manuel Irimia
- Donnelly Centre, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada; EMBL/CRG Research Unit in Systems Biology, Centre for Genomic Regulation (CRG), 88 Dr. Aiguader, Barcelona 08003, Spain.
| | - Robert J Weatheritt
- Donnelly Centre, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada; MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Jonathan D Ellis
- Donnelly Centre, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada
| | - Neelroop N Parikshak
- Department of Neurology, Center for Autism Research and Treatment, Semel Institute, David Geffen School of Medicine, University of California Los Angeles, 695 Charles E. Young Drive South, Los Angeles, CA 90095, USA
| | | | - Mariana Babor
- Donnelly Centre, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada
| | | | - Javier Tapial
- EMBL/CRG Research Unit in Systems Biology, Centre for Genomic Regulation (CRG), 88 Dr. Aiguader, Barcelona 08003, Spain
| | - Bushra Raj
- Donnelly Centre, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada
| | - Dave O'Hanlon
- Donnelly Centre, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada
| | - Miriam Barrios-Rodiles
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON M5G 1X5, Canada
| | - Michael J E Sternberg
- Centre for Integrative Systems Biology and Bioinformatics, Department of Life Sciences, Imperial College London, London SW7 2AZ, UK
| | - Sabine P Cordes
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON M5G 1X5, Canada; Department of Molecular Genetics, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada
| | - Frederick P Roth
- Donnelly Centre, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada; Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON M5G 1X5, Canada; Department of Molecular Genetics, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada; Department of Computer Science, University of Toronto, 10 King's College Road, Toronto, ON M5S 3G4, Canada; Canadian Institute For Advanced Research, 180 Dundas Street West, Toronto, ON M5G 1Z8, Canada
| | - Jeffrey L Wrana
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Avenue, Toronto, ON M5G 1X5, Canada; Department of Molecular Genetics, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada
| | - Daniel H Geschwind
- Department of Neurology, Center for Autism Research and Treatment, Semel Institute, David Geffen School of Medicine, University of California Los Angeles, 695 Charles E. Young Drive South, Los Angeles, CA 90095, USA
| | - Benjamin J Blencowe
- Donnelly Centre, University of Toronto, 160 College Street, Toronto, ON M5S 3E1, Canada; Department of Molecular Genetics, University of Toronto, 1 King's College Circle, Toronto, ON M5S 1A8, Canada.
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37
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Borner GHH, Hein MY, Hirst J, Edgar JR, Mann M, Robinson MS. Fractionation profiling: a fast and versatile approach for mapping vesicle proteomes and protein-protein interactions. Mol Biol Cell 2014; 25:3178-94. [PMID: 25165137 PMCID: PMC4196868 DOI: 10.1091/mbc.e14-07-1198] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Revised: 08/06/2014] [Accepted: 08/07/2014] [Indexed: 01/06/2023] Open
Abstract
We developed "fractionation profiling," a method for rapid proteomic analysis of membrane vesicles and protein particles. The approach combines quantitative proteomics with subcellular fractionation to generate signature protein abundance distribution profiles. Functionally associated groups of proteins are revealed through cluster analysis. To validate the method, we first profiled >3500 proteins from HeLa cells and identified known clathrin-coated vesicle proteins with >90% accuracy. We then profiled >2400 proteins from Drosophila S2 cells, and we report the first comprehensive insect clathrin-coated vesicle proteome. Of importance, the cluster analysis extends to all profiled proteins and thus identifies a diverse range of known and novel cytosolic and membrane-associated protein complexes. We show that it also allows the detailed compositional characterization of complexes, including the delineation of subcomplexes and subunit stoichiometry. Our predictions are presented in an interactive database. Fractionation profiling is a universal method for defining the clathrin-coated vesicle proteome and may be adapted for the analysis of other types of vesicles and particles. In addition, it provides a versatile tool for the rapid generation of large-scale protein interaction maps.
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Affiliation(s)
- Georg H H Borner
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Marco Y Hein
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Jennifer Hirst
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, United Kingdom
| | - James R Edgar
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, United Kingdom
| | - Matthias Mann
- Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Margaret S Robinson
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, United Kingdom
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38
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Affiliation(s)
- Yusong Guo
- Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, California 94720-3200;
| | - Daniel W. Sirkis
- Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, California 94720-3200;
| | - Randy Schekman
- Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, California 94720-3200;
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Anitei M, Chenna R, Czupalla C, Esner M, Christ S, Lenhard S, Korn K, Meyenhofer F, Bickle M, Zerial M, Hoflack B. A high-throughput siRNA screen identifies genes that regulate mannose 6-phosphate receptor trafficking. J Cell Sci 2014; 127:5079-92. [PMID: 25278553 DOI: 10.1242/jcs.159608] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The delivery of newly synthesized soluble lysosomal hydrolases to the endosomal system is essential for lysosome function and cell homeostasis. This process relies on the proper trafficking of the mannose 6-phosphate receptors (MPRs) between the trans-Golgi network (TGN), endosomes and the plasma membrane. Many transmembrane proteins regulating diverse biological processes ranging from virus production to the development of multicellular organisms also use these pathways. To explore how cell signaling modulates MPR trafficking, we used high-throughput RNA interference (RNAi) to target the human kinome and phosphatome. Using high-content image analysis, we identified 127 kinases and phosphatases belonging to different signaling networks that regulate MPR trafficking and/or the dynamic states of the subcellular compartments encountered by the MPRs. Our analysis maps the MPR trafficking pathways based on enzymes regulating phosphatidylinositol phosphate metabolism. Furthermore, it reveals how cell signaling controls the biogenesis of post-Golgi tubular carriers destined to enter the endosomal system through a SRC-dependent pathway regulating ARF1 and RAC1 signaling and myosin II activity.
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Affiliation(s)
- Mihaela Anitei
- Biotechnology Center, Technische Universität Dresden, Tatzberg 47-51, 01307 Dresden, Germany
| | - Ramu Chenna
- Biotechnology Center, Technische Universität Dresden, Tatzberg 47-51, 01307 Dresden, Germany
| | - Cornelia Czupalla
- Biotechnology Center, Technische Universität Dresden, Tatzberg 47-51, 01307 Dresden, Germany
| | - Milan Esner
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, Kamenice 3, Building A1, 62500 Brno, Czech Republic
| | - Sara Christ
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany
| | - Steffi Lenhard
- Biotechnology Center, Technische Universität Dresden, Tatzberg 47-51, 01307 Dresden, Germany
| | - Kerstin Korn
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany
| | - Felix Meyenhofer
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany
| | - Marc Bickle
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany
| | - Marino Zerial
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstrasse 108, 01307 Dresden, Germany
| | - Bernard Hoflack
- Biotechnology Center, Technische Universität Dresden, Tatzberg 47-51, 01307 Dresden, Germany
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AP-1/σ1B-Dependent SV Protein Recycling Is Regulated in Early Endosomes and Is Coupled to AP-2 Endocytosis. Mol Neurobiol 2014; 52:142-61. [PMID: 25128028 DOI: 10.1007/s12035-014-8852-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Accepted: 08/04/2014] [Indexed: 12/22/2022]
Abstract
Adaptor protein (AP)-1/σ1B(-/-) mice have reduced synaptic-vesicle (SV) recycling and increased endosomes. Mutant mice have impaired spatial memory, and σ1B-deficient humans have a severe mental retardation. In order to define these σ1B(-/-) 'bulk' endosomes and to determine their functions in SV recycling, we developed a protocol to separate them from the majority of the neuronal endosomes. The σ1B(-/-) 'bulk' endosomes proved to be classic early endosomes with an increase in the phospholipid phosphatidylinositol 3-phosphate (PI-3-P), which recruits proteins mediating protein sorting out of early endosomes into different routes. σ1B deficiency induced alterations in the endosomal proteome reveals two major functions: SV protein storage and sorting into endolysosomes. Alternative endosomal recycling pathways are not up-regulated, but certain SV proteins are misrouted. Tetraspanins are enriched in σ1B(-/-) synaptosomes, but not in their endosomes or in their clathrin-coated-vesicles (CCVs), indicating AP-1/σ1B-dependent sorting. Synapses contain also more AP-2 CCV, although it is expected that they contain less due to reduced SV recycling. Coat composition of these AP-2 CCVs is altered, and thus, they represent a subpopulation of AP-2 CCVs. Association of calmodulin-dependent protein kinase (CaMK)-IIα, -δ and casein kinase (CK)-IIα with the endosome/SV pool is altered, as well as 14-3-3η, indicating changes in specific signalling pathways regulating synaptic plasticity. The accumulation of early endosomes and endocytotic AP-2 CCV indicates the regulation of SV recycling via early endosomes by the interdependent regulation of AP-2-mediated endocytosis and AP-1/σ1B-mediated SV reformation.
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Bonnemaison M, Bäck N, Lin Y, Bonifacino JS, Mains R, Eipper B. AP-1A controls secretory granule biogenesis and trafficking of membrane secretory granule proteins. Traffic 2014; 15:1099-121. [PMID: 25040637 DOI: 10.1111/tra.12194] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Revised: 07/07/2014] [Accepted: 07/07/2014] [Indexed: 02/06/2023]
Abstract
The adaptor protein 1A complex (AP-1A) transports cargo between the trans-Golgi network (TGN) and endosomes. In professional secretory cells, AP-1A also retrieves material from immature secretory granules (SGs). The role of AP-1A in SG biogenesis was explored using AtT-20 corticotrope tumor cells expressing reduced levels of the AP-1A μ1A subunit. A twofold reduction in μ1A resulted in a decrease in TGN cisternae and immature SGs and the appearance of regulated secretory pathway components in non-condensing SGs. Although basal secretion of endogenous SG proteins was unaffected, secretagogue-stimulated release was halved. The reduced μ1A levels interfered with the normal trafficking of carboxypeptidase D (CPD) and peptidylglycine α-amidating monooxygenase-1 (PAM-1), integral membrane enzymes that enter immature SGs. The non-condensing SGs contained POMC products and PAM-1, but not CPD. Based on metabolic labeling and secretion experiments, the cleavage of newly synthesized PAM-1 into PHM was unaltered, but PHM basal secretion was increased in sh-μ1A PAM-1 cells. Despite lacking a canonical AP-1A binding motif, yeast two-hybrid studies demonstrated an interaction between the PAM-1 cytosolic domain and AP-1A. Coimmunoprecipitation experiments with PAM-1 mutants revealed an influence of the luminal domains of PAM-1 on this interaction. Thus, AP-1A is crucial for normal SG biogenesis, function and composition.
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Affiliation(s)
- Mathilde Bonnemaison
- Department of Molecular Biology and Biophysics, University of Connecticut Health Center, Farmington, CT, 06030, USA
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Pereira RR, Pinto IP, Minasi LB, de Melo AV, da Cruz e Cunha DM, Cruz AS, Ribeiro CL, da Silva CC, de Melo e Silva D, da Cruz AD. Screening for intellectual disability using high-resolution CMA technology in a retrospective cohort from Central Brazil. PLoS One 2014; 9:e103117. [PMID: 25061755 PMCID: PMC4111347 DOI: 10.1371/journal.pone.0103117] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Accepted: 06/27/2014] [Indexed: 11/20/2022] Open
Abstract
Intellectual disability is a complex, variable, and heterogeneous disorder, representing a disabling condition diagnosed worldwide, and the etiologies are multiple and highly heterogeneous. Microscopic chromosomal abnormalities and well-characterized genetic conditions are the most common causes of intellectual disability. Chromosomal Microarray Analysis analyses have made it possible to identify putatively pathogenic copy number variation that could explain the molecular etiology of intellectual disability. The aim of the current study was to identify possible submicroscopic genomic alterations using a high-density chromosomal microarray in a retrospective cohort of patients with otherwise undiagnosable intellectual disabilities referred by doctors from the public health system in Central Brazil. The CytoScan HD technology was used to detect changes in the genome copy number variation of patients who had intellectual disability and a normal karyotype. The analysis detected 18 CNVs in 60% of patients. Pathogenic CNVs represented about 22%, so it was possible to propose the etiology of intellectual disability for these patients. Likely pathogenic and unknown clinical significance CNVs represented 28% and 50%, respectively. Inherited and de novo CNVs were equally distributed. We report the nature of CNVs in patients from Central Brazil, representing a population not yet screened by microarray technologies.
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Affiliation(s)
- Rodrigo Roncato Pereira
- Núcleo de Pesquisas Replicon, Departamento de Biologia, Pontifícia Universidade Católica de Goiás, Goiânia, Goiás, Brazil
- Programa de Pós-Graduação em Biologia Celular e Molecular, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | - Irene Plaza Pinto
- Núcleo de Pesquisas Replicon, Departamento de Biologia, Pontifícia Universidade Católica de Goiás, Goiânia, Goiás, Brazil
- Programa de Pós-Graduação (Mestrado) em Genética, Pontifícia Universidade Católica de Goiás, Goiânia, Goiás, Brazil
| | - Lysa Bernardes Minasi
- Programa de Pós-Graduação (Mestrado) em Genética, Pontifícia Universidade Católica de Goiás, Goiânia, Goiás, Brazil
| | - Aldaires Vieira de Melo
- Núcleo de Pesquisas Replicon, Departamento de Biologia, Pontifícia Universidade Católica de Goiás, Goiânia, Goiás, Brazil
- Programa de Pós-Graduação em Biotecnologia e Biodiversidade, Universidade de Brasília, Brasília, DF, Brazil
| | - Damiana Mirian da Cruz e Cunha
- Núcleo de Pesquisas Replicon, Departamento de Biologia, Pontifícia Universidade Católica de Goiás, Goiânia, Goiás, Brazil
- Programa de Pós-Graduação (Mestrado) em Genética, Pontifícia Universidade Católica de Goiás, Goiânia, Goiás, Brazil
| | - Alex Silva Cruz
- Núcleo de Pesquisas Replicon, Departamento de Biologia, Pontifícia Universidade Católica de Goiás, Goiânia, Goiás, Brazil
- Programa de Pós-Graduação em Biologia Celular e Molecular, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
| | - Cristiano Luiz Ribeiro
- Núcleo de Pesquisas Replicon, Departamento de Biologia, Pontifícia Universidade Católica de Goiás, Goiânia, Goiás, Brazil
| | - Cláudio Carlos da Silva
- Núcleo de Pesquisas Replicon, Departamento de Biologia, Pontifícia Universidade Católica de Goiás, Goiânia, Goiás, Brazil
- Programa de Pós-Graduação (Mestrado) em Genética, Pontifícia Universidade Católica de Goiás, Goiânia, Goiás, Brazil
- Laboratório de Citogenética Humana e Genética Molecular, Secretaria do Estado da Saúde de Goiás (LACEN/SESGO), Goiânia, GO, Brazil
| | - Daniela de Melo e Silva
- Núcleo de Pesquisas Replicon, Departamento de Biologia, Pontifícia Universidade Católica de Goiás, Goiânia, Goiás, Brazil
- Programa de Pós-Graduação em Genética e Biologia Molecular, Laboratório de Genética e Biodiversidade, Universidade Federal de Goiás, Goiânia, GO, Brazil
| | - Aparecido Divino da Cruz
- Núcleo de Pesquisas Replicon, Departamento de Biologia, Pontifícia Universidade Católica de Goiás, Goiânia, Goiás, Brazil
- Programa de Pós-Graduação em Biologia Celular e Molecular, Universidade Federal de Goiás, Goiânia, Goiás, Brazil
- Programa de Pós-Graduação (Mestrado) em Genética, Pontifícia Universidade Católica de Goiás, Goiânia, Goiás, Brazil
- Programa de Pós-Graduação em Biotecnologia e Biodiversidade, Universidade de Brasília, Brasília, DF, Brazil
- Laboratório de Citogenética Humana e Genética Molecular, Secretaria do Estado da Saúde de Goiás (LACEN/SESGO), Goiânia, GO, Brazil
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Pinto IP, Minasi LB, da Cruz AS, de Melo AV, da Cruz e Cunha DM, Pereira RR, Ribeiro CL, da Silva CC, de Melo e Silva D, da Cruz AD. A non-syndromic intellectual disability associated with a de novo microdeletion at 7q and 18p, microduplication at Xp, and 18q partial trisomy detected using chromosomal microarray analysis approach. Mol Cytogenet 2014; 7:44. [PMID: 25028595 PMCID: PMC4099144 DOI: 10.1186/1755-8166-7-44] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Accepted: 06/20/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Chromosome abnormalities that segregate with a disease phenotype can facilitate the identification of disease loci and genes. The relationship between chromosome 18 anomalies with severe intellectual disability has attracted the attention of cytogeneticists worldwide. Duplications of the X chromosome can cause intellectual disability in females with variable phenotypic effects, due in part to variations in X-inactivation patterns. Additionally, deletions of the 7qter region are associated with a range of phenotypes. RESULTS We report the first case of de novo microdeletion at 7q and 18p, 18q partial trisomy, microduplication at Xp associated to intellectual disability in a Brazilian child, presenting a normal karyotype. Karyotyping showed any chromosome alteration. Chromosomal microarray analysis detected a de novo microdeletion at 18p11.32 and 18q partial trisomy, an inherited microdeletion at 7q31.1 and a de novo microduplication at Xp22.33p21.3. CONCLUSIONS Our report illustrates a case that presents complex genomic imbalances which may contribute to a severe clinical phenotypes. The rare and complex phenotypes have to be investigated to define the subsets and allow the phenotypes classification.
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Affiliation(s)
- Irene Plaza Pinto
- Departamento de Biologia, Pontifícia Universidade Católica de Goiás, Núcleo de Pesquisas Replicon, Rua 235, n. 40, Bloco L, Área IV Setor Universitário, Goiânia, GO, Brazil
- Departamento de Biologia, Pontifícia Universidade Católica de Goiás, Mestrado em Genética, Programa de Pós Graduação Mestrado em Genética, Rua 235, n. 40, Bloco L, Área IV Setor Universitário, Goiânia, GO, Brazil
| | - Lysa Bernardes Minasi
- Departamento de Biologia, Pontifícia Universidade Católica de Goiás, Núcleo de Pesquisas Replicon, Rua 235, n. 40, Bloco L, Área IV Setor Universitário, Goiânia, GO, Brazil
- Departamento de Biologia, Pontifícia Universidade Católica de Goiás, Mestrado em Genética, Programa de Pós Graduação Mestrado em Genética, Rua 235, n. 40, Bloco L, Área IV Setor Universitário, Goiânia, GO, Brazil
| | - Alex Silva da Cruz
- Departamento de Biologia, Pontifícia Universidade Católica de Goiás, Núcleo de Pesquisas Replicon, Rua 235, n. 40, Bloco L, Área IV Setor Universitário, Goiânia, GO, Brazil
- Universidade Federal de Goiás, Instituto de Ciências Biológicas, Programa de Pós Graduação em Biologia, Campus Samambaia, Goiânia, GO, Brazil
| | - Aldaires Vieira de Melo
- Universidade Federal de Goiás, Programa de Pós Graduação em Biotecnologia e Biodiversidade, Rede Centro Oeste de Pós Graduação, Pesquisa e Inovação, Campus Samambaia, Goiânia, GO, Brazil
| | - Damiana Míriam da Cruz e Cunha
- Departamento de Biologia, Pontifícia Universidade Católica de Goiás, Núcleo de Pesquisas Replicon, Rua 235, n. 40, Bloco L, Área IV Setor Universitário, Goiânia, GO, Brazil
- Departamento de Biologia, Pontifícia Universidade Católica de Goiás, Mestrado em Genética, Programa de Pós Graduação Mestrado em Genética, Rua 235, n. 40, Bloco L, Área IV Setor Universitário, Goiânia, GO, Brazil
| | - Rodrigo Roncato Pereira
- Universidade Federal de Goiás, Instituto de Ciências Biológicas, Programa de Pós Graduação em Biologia, Campus Samambaia, Goiânia, GO, Brazil
| | - Cristiano Luiz Ribeiro
- Departamento de Biologia, Pontifícia Universidade Católica de Goiás, Núcleo de Pesquisas Replicon, Rua 235, n. 40, Bloco L, Área IV Setor Universitário, Goiânia, GO, Brazil
| | - Claudio Carlos da Silva
- Departamento de Biologia, Pontifícia Universidade Católica de Goiás, Núcleo de Pesquisas Replicon, Rua 235, n. 40, Bloco L, Área IV Setor Universitário, Goiânia, GO, Brazil
- Departamento de Biologia, Pontifícia Universidade Católica de Goiás, Mestrado em Genética, Programa de Pós Graduação Mestrado em Genética, Rua 235, n. 40, Bloco L, Área IV Setor Universitário, Goiânia, GO, Brazil
- Laboratório de Citogenética Humana e Genética Molecular, Secretaria do Estado da Saúde de Goiás (LACEN/SESGO), Goiânia, GO, Brazil
| | - Daniela de Melo e Silva
- Departamento de Biologia, Pontifícia Universidade Católica de Goiás, Núcleo de Pesquisas Replicon, Rua 235, n. 40, Bloco L, Área IV Setor Universitário, Goiânia, GO, Brazil
- Programa de Pós-Graduação em Genética e Biologia Molecular, Laboratório de Genética e Biodiversidade, Universidade Federal de Goiás, Goiânia, GO, Brazil
| | - Aparecido Divino da Cruz
- Departamento de Biologia, Pontifícia Universidade Católica de Goiás, Núcleo de Pesquisas Replicon, Rua 235, n. 40, Bloco L, Área IV Setor Universitário, Goiânia, GO, Brazil
- Universidade Federal de Goiás, Instituto de Ciências Biológicas, Programa de Pós Graduação em Biologia, Campus Samambaia, Goiânia, GO, Brazil
- Departamento de Biologia, Pontifícia Universidade Católica de Goiás, Mestrado em Genética, Programa de Pós Graduação Mestrado em Genética, Rua 235, n. 40, Bloco L, Área IV Setor Universitário, Goiânia, GO, Brazil
- Universidade Federal de Goiás, Programa de Pós Graduação em Biotecnologia e Biodiversidade, Rede Centro Oeste de Pós Graduação, Pesquisa e Inovação, Campus Samambaia, Goiânia, GO, Brazil
- Laboratório de Citogenética Humana e Genética Molecular, Secretaria do Estado da Saúde de Goiás (LACEN/SESGO), Goiânia, GO, Brazil
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An AP4B1 frameshift mutation in siblings with intellectual disability and spastic tetraplegia further delineates the AP-4 deficiency syndrome. Eur J Hum Genet 2014; 23:256-9. [PMID: 24781758 DOI: 10.1038/ejhg.2014.73] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Revised: 03/04/2014] [Accepted: 03/07/2014] [Indexed: 01/28/2023] Open
Abstract
The recently proposed adaptor protein 4 (AP-4) deficiency syndrome comprises a group of congenital neurological disorders characterized by severe intellectual disability (ID), delayed or absent speech, hereditary spastic paraplegia, and growth retardation. AP-4 is a heterotetrameric protein complex with important functions in vesicle trafficking. Mutations in genes affecting different subunits of AP-4, including AP4B1, AP4E1, AP4S1, and AP4M1, have been reported in patients with the AP-4 deficiency phenotype. We describe two siblings from a non-consanguineous couple who presented with severe ID, absent speech, microcephaly, growth retardation, and progressive spastic tetraplegia. Whole-exome sequencing in the two patients identified the novel homozygous 2-bp deletion c.1160_1161delCA (p.(Thr387Argfs*30)) in AP4B1. Sanger sequencing confirmed the mutation in the siblings and revealed it in the heterozygous state in both parents. The AP4B1-associated phenotype has previously been assigned to spastic paraplegia-47. Identification of a novel AP4B1 alteration in two patients with clinical manifestations highly similar to other individuals with mutations affecting one of the four AP-4 subunits further supports the observation that loss of AP-4 assembly or functionality underlies the common clinical features in these patients and underscores the existence of the clinically recognizable AP-4 deficiency syndrome.
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45
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Martinelli D, Dionisi-Vici C. AP1S1 defect causing MEDNIK syndrome: a new adaptinopathy associated with defective copper metabolism. Ann N Y Acad Sci 2014; 1314:55-63. [DOI: 10.1111/nyas.12426] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Diego Martinelli
- Unit of Metabolism; Department of Pediatrics; Bambino Gesu Children's Hospital; Rome Italy
- Section on Translational Neuroscience; Molecular Medicine Program; NICHD/NIH; Bethesda Maryland
| | - Carlo Dionisi-Vici
- Unit of Metabolism; Department of Pediatrics; Bambino Gesu Children's Hospital; Rome Italy
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46
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Abstract
Polarized cells such as epithelial cells and neurons exhibit different plasma membrane domains with distinct protein compositions. Recent studies have shown that sorting of transmembrane proteins to the basolateral domain of epithelial cells and the somatodendritic domain of neurons is mediated by recognition of signals in the cytosolic domains of the proteins by adaptors. These adaptors are components of protein coats associated with the trans-Golgi network and/or recycling endosomes. The clathrin-associated adaptor protein 1 (AP-1) complex plays a preeminent role in this process, although other adaptors and coat proteins, such as AP-4, ARH, Numb, exomer, and retromer, have also been implicated.
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Affiliation(s)
- Juan S Bonifacino
- Cell Biology and Metabolism Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892
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47
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Morgan JR, Comstra HS, Cohen M, Faundez V. Presynaptic membrane retrieval and endosome biology: defining molecularly heterogeneous synaptic vesicles. Cold Spring Harb Perspect Biol 2013; 5:a016915. [PMID: 24086045 DOI: 10.1101/cshperspect.a016915] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The release and uptake of neurotransmitters by synaptic vesicles is a tightly controlled process that occurs in response to diverse stimuli at morphologically disparate synapses. To meet these architectural and functional synaptic demands, it follows that there should be diversity in the mechanisms that control their secretion and retrieval and possibly in the composition of synaptic vesicles within the same terminal. Here we pay particular attention to areas where such diversity is generated, such as the variance in exocytosis/endocytosis coupling, SNAREs defining functionally diverse synaptic vesicle populations and the adaptor-dependent sorting machineries capable of generating vesicle diversity. We argue that there are various synaptic vesicle recycling pathways at any given synapse and discuss several lines of evidence that support the role of the endosome in synaptic vesicle recycling.
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Affiliation(s)
- Jennifer R Morgan
- Eugene Bell Center for Regenerative Biology and Tissue Engineering, Marine Biological Laboratory, Woods Hole, Massachusetts 02543
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Xu P, Baldridge RD, Chi RJ, Burd CG, Graham TR. Phosphatidylserine flipping enhances membrane curvature and negative charge required for vesicular transport. ACTA ACUST UNITED AC 2013; 202:875-86. [PMID: 24019533 PMCID: PMC3776346 DOI: 10.1083/jcb.201305094] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The Drs2 flippase increases membrane curvature and anionic phospholipid composition of the membrane by flipping phosphatidylserine, which is critical for vesicular transport between the trans-Golgi network and early endosomes. Vesicle-mediated protein transport between organelles of the secretory and endocytic pathways is strongly influenced by the composition and organization of membrane lipids. In budding yeast, protein transport between the trans-Golgi network (TGN) and early endosome (EE) requires Drs2, a phospholipid translocase in the type IV P-type ATPase family. However, downstream effectors of Drs2 and specific phospholipid substrate requirements for protein transport in this pathway are unknown. Here, we show that the Arf GTPase-activating protein (ArfGAP) Gcs1 is a Drs2 effector that requires a variant of the ArfGAP lipid packing sensor (+ALPS) motif for localization to TGN/EE membranes. Drs2 increases membrane curvature and anionic phospholipid composition of the cytosolic leaflet, both of which are sensed by the +ALPS motif. Using mutant forms of Drs2 and the related protein Dnf1, which alter their ability to recognize phosphatidylserine, we show that translocation of this substrate to the cytosolic leaflet is essential for +ALPS binding and vesicular transport between the EE and the TGN.
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Affiliation(s)
- Peng Xu
- Department of Biological Sciences, Vanderbilt University, Nashville, TN 37235
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Cacciagli P, Desvignes JP, Girard N, Delepine M, Zelenika D, Lathrop M, Lévy N, Ledbetter DH, Dobyns WB, Villard L. AP1S2 is mutated in X-linked Dandy-Walker malformation with intellectual disability, basal ganglia disease and seizures (Pettigrew syndrome). Eur J Hum Genet 2013; 22:363-8. [PMID: 23756445 DOI: 10.1038/ejhg.2013.135] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Revised: 05/14/2013] [Accepted: 05/15/2013] [Indexed: 11/09/2022] Open
Abstract
MRXS5 or Pettigrew syndrome was described 20 years ago in a four generation family including nine affected individuals presenting with facial dysmorphism, intellectual disability, Dandy-Walker malformation and inconstant choreoathetosis. Four individuals had iron deposition in the basal ganglia seen on MRI or at autopsy. The mutation causing Pettigrew has remained elusive since the initial description of the condition. We report the identification of a mutation in the X-linked AP1S2 gene in the original Pettigrew syndrome family using X-chromosome exome sequencing. We report additional phenotype details for several of the affected individuals, allowing us to further refine the phenotype corresponding to this X-linked intellectual disability syndrome. The AP1S2 c.426+1 G>T mutation segregates with the disease in the Pettigrew syndrome family and results in loss of 46 amino acids in the clathrin adaptor complex small chain domain that spans most of the AP1S2 protein sequence. The mutation reported here in AP1S2 is the first mutation that is not predicted to cause a premature termination of the coding sequence or absence of the AP1S2 protein. Although most of the families affected by a mutation in AP1S2 were initially described as having different disorders assigned to at least three different OMIM numbers (MIM 300629, 300630 and 304340), our analysis of the phenotype shows that they are all the same syndrome with recognition complicated by highly variable expressivity that is seen within as well as between families and is probably not explained by differences in mutation severity.
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Affiliation(s)
- Pierre Cacciagli
- 1] Inserm, U910, Faculté de Médecine de La Timone, Marseille, France [2] Aix Marseille Université, Faculté de Médecine, Marseille, France [3] Assistance Publique Hôpitaux de Marseille, Département de Génétique Médicale et de Biologie Cellulaire, Hôpital d'Enfants de La Timone, Marseille, France
| | - Jean-Pierre Desvignes
- 1] Inserm, U910, Faculté de Médecine de La Timone, Marseille, France [2] Aix Marseille Université, Faculté de Médecine, Marseille, France
| | - Nadine Girard
- Assistance Publique Hôpitaux de Marseille, Service de Neuroradiologie, Hôpital de La Timone, Marseille, France
| | - Marc Delepine
- Commissariat à l'Energie Atomique, Institut Génomique, Centre National de Génotypage, Evry, France
| | - Diana Zelenika
- Commissariat à l'Energie Atomique, Institut Génomique, Centre National de Génotypage, Evry, France
| | - Mark Lathrop
- 1] Commissariat à l'Energie Atomique, Institut Génomique, Centre National de Génotypage, Evry, France [2] Fondation Jean Dausset - CEPH, Paris, France
| | - Nicolas Lévy
- 1] Inserm, U910, Faculté de Médecine de La Timone, Marseille, France [2] Aix Marseille Université, Faculté de Médecine, Marseille, France [3] Assistance Publique Hôpitaux de Marseille, Département de Génétique Médicale et de Biologie Cellulaire, Hôpital d'Enfants de La Timone, Marseille, France
| | | | - William B Dobyns
- Departments of Pediatrics and Neurology, University of Washington, Center for Integrative Brain Research, Seattle Children's Hospital, Seattle, Washington, USA
| | - Laurent Villard
- 1] Inserm, U910, Faculté de Médecine de La Timone, Marseille, France [2] Aix Marseille Université, Faculté de Médecine, Marseille, France
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Hirst J, Irving C, Borner GH. Adaptor Protein Complexes AP-4 and AP-5: New Players in Endosomal Trafficking and Progressive Spastic Paraplegia. Traffic 2012; 14:153-64. [DOI: 10.1111/tra.12028] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Revised: 11/15/2012] [Accepted: 11/21/2012] [Indexed: 12/16/2022]
Affiliation(s)
- Jennifer Hirst
- Cambridge Institute for Medical Research; University of Cambridge; Wellcome Trust/MRC Building; Cambridge; CB2 0XY; UK
| | - Carol Irving
- MRC Centre for Developmental Neurobiology; King's College; London; SE1 1UL; UK
| | - Georg H.H. Borner
- Cambridge Institute for Medical Research; University of Cambridge; Wellcome Trust/MRC Building; Cambridge; CB2 0XY; UK
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