101
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Chen K, Healy MD, Collins BM. Towards a molecular understanding of endosomal trafficking by Retromer and Retriever. Traffic 2019; 20:465-478. [DOI: 10.1111/tra.12649] [Citation(s) in RCA: 92] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 04/15/2019] [Accepted: 04/15/2019] [Indexed: 12/16/2022]
Affiliation(s)
- Kai‐En Chen
- Institute for Molecular Bioscience University of Queensland St. Lucia Queensland Australia
| | - Michael D. Healy
- Institute for Molecular Bioscience University of Queensland St. Lucia Queensland Australia
| | - Brett M. Collins
- Institute for Molecular Bioscience University of Queensland St. Lucia Queensland Australia
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102
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Baños-Mateos S, Rojas AL, Hierro A. VPS29, a tweak tool of endosomal recycling. Curr Opin Cell Biol 2019; 59:81-87. [PMID: 31051431 DOI: 10.1016/j.ceb.2019.03.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 03/09/2019] [Accepted: 03/19/2019] [Indexed: 10/26/2022]
Abstract
The endolysosomal system is a highly dynamic network of membranes for degradation and recycling. During endosomal maturation, cargo molecules destined for lysosomal degradation are progressively concentrated through continuous rounds of fusion and fission reactions concomitant with inbound and outbound membrane fluxes. Of the cargo molecules delivered to endosomes, about two-thirds are rescued from degradation and recycled for reuse. This balance between degradation and recycling is essential to preserve the proteostatic plasticity of the cell under variable physiological demands. Cargo retrieval from endosomes involves several sorting complexes with stable core compositions that associate with multidomain regulatory proteins, consequently displaying complex interaction networks. The vacuolar protein sorting 29 (VPS29) has emerged as a central scaffold that coordinates the physical assembly of retrieval complexes with regulatory components in what appears to be an elegant solution for regulating distinct retrieval stations. This review summarizes the VPS29-binding partners and its integration into retrieval complexes for endosomal sorting and trafficking.
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Affiliation(s)
| | | | - Aitor Hierro
- CIC bioGUNE, Bizkaia Technology Park, Derio, Spain; IKERBASQUE, Basque Foundation for Science, Bilbao, Spain.
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103
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Baba T, Toth DJ, Sengupta N, Kim YJ, Balla T. Phosphatidylinositol 4,5-bisphosphate controls Rab7 and PLEKHM1 membrane cycling during autophagosome-lysosome fusion. EMBO J 2019; 38:e100312. [PMID: 31368593 PMCID: PMC6463214 DOI: 10.15252/embj.2018100312] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 01/02/2019] [Accepted: 01/23/2019] [Indexed: 12/12/2022] Open
Abstract
The small GTPase Rab7 is a key organizer of receptor sorting and lysosomal degradation by recruiting of a variety of effectors depending on its GDP/GTP-bound state. However, molecular mechanisms that trigger Rab7 inactivation remain elusive. Here we find that, among the endosomal pools, Rab7-positive compartments possess the highest level of PI4P, which is primarily produced by PI4K2A kinase. Acute conversion of this endosomal PI4P to PI(4,5)P2 causes Rab7 dissociation from late endosomes and releases a regulator of autophagosome-lysosome fusion, PLEKHM1, from the membrane. Rab7 effectors Vps35 and RILP are not affected by acute PI(4,5)P2 production. Deletion of PI4K2A greatly reduces PIP5Kγ-mediated PI(4,5)P2 production in Rab7-positive endosomes leading to impaired Rab7 inactivation and increased number of LC3-positive structures with defective autophagosome-lysosome fusion. These results reveal a late endosomal PI4P-PI(4,5)P2 -dependent regulatory loop that impacts autophagosome flux by affecting Rab7 cycling and PLEKHM1 association.
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Affiliation(s)
- Takashi Baba
- Section on Molecular Signal TransductionProgram for Developmental NeuroscienceEunice Kennedy Shriver National Institute of Child Health and Human DevelopmentNational Institutes of HealthBethesdaMDUSA
| | - Daniel J Toth
- Section on Molecular Signal TransductionProgram for Developmental NeuroscienceEunice Kennedy Shriver National Institute of Child Health and Human DevelopmentNational Institutes of HealthBethesdaMDUSA
| | - Nivedita Sengupta
- Section on Molecular Signal TransductionProgram for Developmental NeuroscienceEunice Kennedy Shriver National Institute of Child Health and Human DevelopmentNational Institutes of HealthBethesdaMDUSA
| | - Yeun Ju Kim
- Section on Molecular Signal TransductionProgram for Developmental NeuroscienceEunice Kennedy Shriver National Institute of Child Health and Human DevelopmentNational Institutes of HealthBethesdaMDUSA
| | - Tamas Balla
- Section on Molecular Signal TransductionProgram for Developmental NeuroscienceEunice Kennedy Shriver National Institute of Child Health and Human DevelopmentNational Institutes of HealthBethesdaMDUSA
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104
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USP32 regulates late endosomal transport and recycling through deubiquitylation of Rab7. Nat Commun 2019; 10:1454. [PMID: 30926795 PMCID: PMC6440979 DOI: 10.1038/s41467-019-09437-x] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Accepted: 03/06/2019] [Indexed: 12/26/2022] Open
Abstract
The endosomal system is a highly dynamic multifunctional organelle, whose complexity is regulated in part by reversible ubiquitylation. Despite the wide-ranging influence of ubiquitin in endosomal processes, relatively few enzymes utilizing ubiquitin have been described to control endosome integrity and function. Here we reveal the deubiquitylating enzyme (DUB) ubiquitin-specific protease 32 (USP32) as a powerful player in this context. Loss of USP32 inhibits late endosome (LE) transport and recycling of LE cargos, resulting in dispersion and swelling of the late compartment. Using SILAC-based ubiquitome profiling we identify the small GTPase Rab7—the logistical centerpiece of LE biology—as a substrate of USP32. Mechanistic studies reveal that LE transport effector RILP prefers ubiquitylation-deficient Rab7, while retromer-mediated LE recycling benefits from an intact cycle of Rab7 ubiquitylation. Collectively, our observations suggest that reversible ubiquitylation helps switch Rab7 between its various functions, thereby maintaining global spatiotemporal order in the endosomal system. Though ubiquitin is known to broadly influence endosomal trafficking, few ubiquitin-utilizing enzymes targeting endosomal regulators are known. Here, the authors find that the deubiquitylating enzyme (DUB) USP32 influences endosomal membrane dynamics by deubiquitinating Rab7.
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105
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Rab7a and Mitophagosome Formation. Cells 2019; 8:cells8030224. [PMID: 30857122 PMCID: PMC6468461 DOI: 10.3390/cells8030224] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2019] [Revised: 02/27/2019] [Accepted: 03/01/2019] [Indexed: 12/14/2022] Open
Abstract
The small GTPase, Rab7a, and the regulators of its GDP/GTP-binding status were shown to have roles in both endocytic membrane traffic and autophagy. Classically known to regulate endosomal retrograde transport and late endosome-lysosome fusion, earlier work has indicated a role for Rab7a in autophagosome-lysosome fusion as well as autolysosome maturation. However, as suggested by recent findings on PTEN-induced kinase 1 (PINK1)-Parkin-mediated mitophagy, Rab7a and its regulators are critical for the correct targeting of Atg9a-bearing vesicles to effect autophagosome formation around damaged mitochondria. This mitophagosome formation role for Rab7a is dependent on an intact Rab cycling process mediated by the Rab7a-specific guanine nucleotide exchange factor (GEF) and GTPase activating proteins (GAPs). Rab7a activity in this regard is also dependent on the retromer complex, as well as phosphorylation by the TRAF family-associated NF-κB activator binding kinase 1 (TBK1). Here, we discuss these recent findings and broadened perspectives on the role of the Rab7a network in PINK1-Parkin mediated mitophagy.
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106
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Del Olmo T, Lauzier A, Normandin C, Larcher R, Lecours M, Jean D, Lessard L, Steinberg F, Boisvert FM, Jean S. APEX2-mediated RAB proximity labeling identifies a role for RAB21 in clathrin-independent cargo sorting. EMBO Rep 2019; 20:e47192. [PMID: 30610016 PMCID: PMC6362359 DOI: 10.15252/embr.201847192] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 12/06/2018] [Accepted: 12/10/2018] [Indexed: 12/26/2022] Open
Abstract
RAB GTPases are central modulators of membrane trafficking. They are under the dynamic regulation of activating guanine exchange factors (GEFs) and inactivating GTPase-activating proteins (GAPs). Once activated, RABs recruit a large spectrum of effectors to control trafficking functions of eukaryotic cells. Multiple proteomic studies, using pull-down or yeast two-hybrid approaches, have identified a number of RAB interactors. However, due to the in vitro nature of these approaches and inherent limitations of each technique, a comprehensive definition of RAB interactors is still lacking. By comparing quantitative affinity purifications of GFP:RAB21 with APEX2-mediated proximity labeling of RAB4a, RAB5a, RAB7a, and RAB21, we find that APEX2 proximity labeling allows for the comprehensive identification of RAB regulators and interactors. Importantly, through biochemical and genetic approaches, we establish a novel link between RAB21 and the WASH and retromer complexes, with functional consequences on cargo sorting. Hence, APEX2-mediated proximity labeling of RAB neighboring proteins represents a new and efficient tool to define RAB functions.
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Affiliation(s)
- Tomas Del Olmo
- Faculté de Médecine et des Sciences de la Santé, Département d'Anatomie et de Biologie Cellulaire, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Annie Lauzier
- Faculté de Médecine et des Sciences de la Santé, Département d'Anatomie et de Biologie Cellulaire, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Caroline Normandin
- Faculté de Médecine et des Sciences de la Santé, Département d'Anatomie et de Biologie Cellulaire, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Raphaëlle Larcher
- Faculté de Médecine et des Sciences de la Santé, Département d'Anatomie et de Biologie Cellulaire, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Mia Lecours
- Faculté de Médecine et des Sciences de la Santé, Département d'Anatomie et de Biologie Cellulaire, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Dominique Jean
- Faculté de Médecine et des Sciences de la Santé, Département d'Anatomie et de Biologie Cellulaire, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Louis Lessard
- Faculté de Médecine et des Sciences de la Santé, Département d'Anatomie et de Biologie Cellulaire, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Florian Steinberg
- Center for Biological Systems Analysis (ZBSA), Faculty of Biology, Albert Ludwigs Universitaet Freiburg, Freiburg, Germany
| | - François-Michel Boisvert
- Faculté de Médecine et des Sciences de la Santé, Département d'Anatomie et de Biologie Cellulaire, Université de Sherbrooke, Sherbrooke, QC, Canada
| | - Steve Jean
- Faculté de Médecine et des Sciences de la Santé, Département d'Anatomie et de Biologie Cellulaire, Université de Sherbrooke, Sherbrooke, QC, Canada
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107
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Rahman AA, Morrison BE. Contributions of VPS35 Mutations to Parkinson's Disease. Neuroscience 2019; 401:1-10. [PMID: 30660673 DOI: 10.1016/j.neuroscience.2019.01.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 12/18/2018] [Accepted: 01/08/2019] [Indexed: 12/14/2022]
Abstract
Parkinson's Disease (PD) is a multi-system neurodegenerative disease where approximately 90% of cases are idiopathic. The remaining 10% of the cases can be traced to a genetic origin and research has largely focused on these associated genes to gain a better understanding of the molecular and cellular pathogenesis for PD. The gene encoding vacuolar protein sorting protein 35 (VPS35) has been definitively linked to late onset familial PD following the identification of a point mutation (D620N) as the causal agent in a Swiss family. Since its discovery, numerous studies have been undertaken to characterize the role of VPS35 in cellular processes and efforts have been directed toward understanding the perturbations caused by the D620N mutation. In this review, we examine what is currently known about VPS35, which has pleiotropic effects, as well as proposed mechanisms of pathogenesis by the D620N mutation. A brief survey of other VPS35 polymorphisms is also provided. Lastly, model systems that are being utilized for these investigations and possible directions for future research are discussed.
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Affiliation(s)
- Abir A Rahman
- Department of Biological Sciences, Boise State University, Boise, ID 83725, USA; Biomolecular Sciences Ph.D. Program, Boise State University, Boise, ID 83725, USA
| | - Brad E Morrison
- Department of Biological Sciences, Boise State University, Boise, ID 83725, USA; Biomolecular Sciences Ph.D. Program, Boise State University, Boise, ID 83725, USA.
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108
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Mohapatra G, Gaur P, Mujagond P, Singh M, Rana S, Pratap S, Kaur N, Verma S, Krishnan V, Singh N, Srikanth CV. A SUMOylation-dependent switch of RAB7 governs intracellular life and pathogenesis of Salmonella Typhimurium. J Cell Sci 2019; 132:jcs.222612. [PMID: 30510112 DOI: 10.1242/jcs.222612] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Accepted: 11/26/2018] [Indexed: 01/06/2023] Open
Abstract
Salmonella Typhimurium is an intracellular pathogen that causes gastroenteritis in humans. Aided by a battery of effector proteins, S. Typhimurium resides intracellularly in a specialized vesicle, called the Salmonella-containing vacuole (SCV) that utilizes the host endocytic vesicular transport pathway (VTP). Here, we probed the possible role of SUMOylation, a post-translation modification pathway, in SCV biology. Proteome analysis by complex mass-spectrometry (MS/MS) revealed a dramatically altered SUMO-proteome (SUMOylome) in S. Typhimurium-infected cells. RAB7, a component of VTP, was key among several crucial proteins identified in our study. Detailed MS/MS assays, in vitro SUMOylation assays and structural docking analysis revealed SUMOylation of RAB7 (RAB7A) specifically at lysine 175. A SUMOylation-deficient RAB7 mutant (RAB7K175R) displayed longer half-life, was beneficial to SCV dynamics and functionally deficient. Collectively, the data revealed that RAB7 SUMOylation blockade by S. Typhimurium ensures availability of long-lived but functionally compromised RAB7, which was beneficial to the pathogen. Overall, this SUMOylation-dependent switch of RAB7 controlled by S. Typhimurium is an unexpected mode of VTP pathway regulation, and unveils a mechanism of broad interest well beyond Salmonella-host crosstalk. This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Gayatree Mohapatra
- Laboratory of Gut Inflammation and Infection Biology, Regional Centre for Biotechnology NCR Biotech Science Cluster 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad - 121 001 Haryana (NCR Delhi), India.,Manipal Acadamy of Higher Education, Manipal, Karnataka 576104, India
| | - Preksha Gaur
- Laboratory of Gut Inflammation and Infection Biology, Regional Centre for Biotechnology NCR Biotech Science Cluster 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad - 121 001 Haryana (NCR Delhi), India
| | - Prabhakar Mujagond
- Laboratory of Gut Inflammation and Infection Biology, Regional Centre for Biotechnology NCR Biotech Science Cluster 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad - 121 001 Haryana (NCR Delhi), India
| | - Mukesh Singh
- Pediatric Biology Centre, Translational Health Science and Technology Institute, NCR Biotech Science Cluster, 3rd Milestone, Faridabad - Gurgaon Expressway, PO box #04, Faridabad - 121001 Haryana, India
| | - Sarika Rana
- Laboratory of Gut Inflammation and Infection Biology, Regional Centre for Biotechnology NCR Biotech Science Cluster 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad - 121 001 Haryana (NCR Delhi), India.,Manipal Acadamy of Higher Education, Manipal, Karnataka 576104, India
| | - Shivendra Pratap
- Laboratory of Gut Inflammation and Infection Biology, Regional Centre for Biotechnology NCR Biotech Science Cluster 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad - 121 001 Haryana (NCR Delhi), India
| | - Navneet Kaur
- Department of Biochemistry and Molecular Biology, University of Nebraska Medical Centre, Omaha, NE 68198, USA
| | - Smriti Verma
- Mucosal Immunology and Biology Research Center, Massachusetts General Hospital, Building 114, 16th Street, Charlestown, MA 02129, USA
| | - Vengadesan Krishnan
- Laboratory of Gut Inflammation and Infection Biology, Regional Centre for Biotechnology NCR Biotech Science Cluster 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad - 121 001 Haryana (NCR Delhi), India
| | - Nirpendra Singh
- Laboratory of Gut Inflammation and Infection Biology, Regional Centre for Biotechnology NCR Biotech Science Cluster 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad - 121 001 Haryana (NCR Delhi), India
| | - C V Srikanth
- Laboratory of Gut Inflammation and Infection Biology, Regional Centre for Biotechnology NCR Biotech Science Cluster 3rd Milestone, Faridabad-Gurgaon Expressway, Faridabad - 121 001 Haryana (NCR Delhi), India
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109
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Cui Y, Carosi JM, Yang Z, Ariotti N, Kerr MC, Parton RG, Sargeant TJ, Teasdale RD. Retromer has a selective function in cargo sorting via endosome transport carriers. J Cell Biol 2018; 218:615-631. [PMID: 30559172 PMCID: PMC6363445 DOI: 10.1083/jcb.201806153] [Citation(s) in RCA: 101] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 10/22/2018] [Accepted: 11/19/2018] [Indexed: 12/11/2022] Open
Abstract
The molecular actions of retromer in the endolysosomal system remain unclear and controversial. Cui et al. demonstrate the essential role of retromer in the selective incorporation of cargo into a specific type of endosome transport carrier and the maintenance of lysosomal function. Retromer is a peripheral membrane protein complex that coordinates multiple vesicular trafficking events within the endolysosomal system. Here, we demonstrate that retromer is required for the maintenance of normal lysosomal morphology and function. The knockout of retromer subunit Vps35 causes an ultrastructural alteration in lysosomal structure and aberrant lysosome function, leading to impaired autophagy. At the whole-cell level, knockout of retromer Vps35 subunit reduces lysosomal proteolytic capacity as a consequence of the improper processing of lysosomal hydrolases, which is dependent on the trafficking of the cation-independent mannose 6-phosphate receptor (CI-M6PR). Incorporation of CI-M6PR into endosome transport carriers via a retromer-dependent process is restricted to those tethered by GCC88 but not golgin-97 or golgin-245. Finally, we show that this retromer-dependent retrograde cargo trafficking pathway requires SNX3, but not other retromer-associated cargo binding proteins, such as SNX27 or SNX-BAR proteins. Therefore, retromer does contribute to the retrograde trafficking of CI-M6PR required for maturation of lysosomal hydrolases and lysosomal function.
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Affiliation(s)
- Yi Cui
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, Brisbane, Queensland, Australia
| | - Julian M Carosi
- Hopwood Centre for Neurobiology, Nutrition and Metabolism Theme, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia.,Centre for Cancer Biology, University of South Australia, Adelaide, South Australia, Australia
| | - Zhe Yang
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, Brisbane, Queensland, Australia
| | - Nicholas Ariotti
- Institute for Molecular Biosciences and Centre for Microscopy and Microanalysis, The University of Queensland, Brisbane, Queensland, Australia
| | - Markus C Kerr
- Institute for Molecular Biosciences and Centre for Microscopy and Microanalysis, The University of Queensland, Brisbane, Queensland, Australia
| | - Robert G Parton
- Institute for Molecular Biosciences and Centre for Microscopy and Microanalysis, The University of Queensland, Brisbane, Queensland, Australia
| | - Timothy J Sargeant
- Hopwood Centre for Neurobiology, Nutrition and Metabolism Theme, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia.,School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, South Australia, Australia
| | - Rohan D Teasdale
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, Brisbane, Queensland, Australia
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110
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Cullen PJ, Steinberg F. To degrade or not to degrade: mechanisms and significance of endocytic recycling. Nat Rev Mol Cell Biol 2018; 19:679-696. [PMID: 30194414 DOI: 10.1038/s41580-018-0053-7] [Citation(s) in RCA: 314] [Impact Index Per Article: 52.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Newly endocytosed integral cell surface proteins are typically either directed for degradation or subjected to recycling back to the plasma membrane. The sorting of integral cell surface proteins, including signalling receptors, nutrient transporters, ion channels, adhesion molecules and polarity markers, within the endolysosomal network for recycling is increasingly recognized as an essential feature in regulating the complexities of physiology at the cell, tissue and organism levels. Historically, endocytic recycling has been regarded as a relatively passive process, where the majority of internalized integral proteins are recycled via a nonspecific sequence-independent 'bulk membrane flow' pathway. Recent work has increasingly challenged this view. The discovery of sequence-specific sorting motifs and the identification of cargo adaptors and associated coat complexes have begun to uncover the highly orchestrated nature of endosomal cargo recycling, thereby providing new insight into the function and (patho)physiology of this process.
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Affiliation(s)
- Peter J Cullen
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol, UK.
| | - Florian Steinberg
- Center for Biological Systems Analysis, Albert Ludwigs Universitaet Freiburg, Freiburg im Breisgau, Germany.
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111
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Stroupe C. This Is the End: Regulation of Rab7 Nucleotide Binding in Endolysosomal Trafficking and Autophagy. Front Cell Dev Biol 2018; 6:129. [PMID: 30333976 PMCID: PMC6176412 DOI: 10.3389/fcell.2018.00129] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 09/14/2018] [Indexed: 01/07/2023] Open
Abstract
Rab7 – or in yeast, Ypt7p – governs membrane trafficking in the late endocytic and autophagic pathways. Rab7 also regulates mitochondrion-lysosome contacts, the sites of mitochondrial fission. Like all Rab GTPases, Rab7 cycles between an “active” GTP-bound form that binds downstream effectors – e.g., the HOPS and retromer complexes and the dynactin-binding Rab-interacting lysosomal protein (RILP) – and an “inactive” GDP-bound form that cannot bind effectors. Accessory proteins regulate the nucleotide binding state of Rab7: guanine nucleotide exchange factors (GEFs) stimulate exchange of bound GDP for GTP, resulting in Rab7 activation, whereas GTPase activating proteins (GAPs) boost Rab7’s GTP hydrolysis activity, thereby inactivating Rab7. This review will discuss the GEF and GAPs that control Rab7 nucleotide binding, and thus regulate Rab7’s activity in endolysosomal trafficking and autophagy. It will also consider how bacterial pathogens manipulate Rab7 nucleotide binding to support intracellular invasion and immune evasion.
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Affiliation(s)
- Christopher Stroupe
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, VA, United States
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112
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Patrick KL, Wojcechowskyj JA, Bell SL, Riba MN, Jing T, Talmage S, Xu P, Cabello AL, Xu J, Shales M, Jimenez-Morales D, Ficht TA, de Figueiredo P, Samuel JE, Li P, Krogan NJ, Watson RO. Quantitative Yeast Genetic Interaction Profiling of Bacterial Effector Proteins Uncovers a Role for the Human Retromer in Salmonella Infection. Cell Syst 2018; 7:323-338.e6. [PMID: 30077634 PMCID: PMC6160342 DOI: 10.1016/j.cels.2018.06.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 05/21/2018] [Accepted: 06/21/2018] [Indexed: 11/26/2022]
Abstract
Intracellular bacterial pathogens secrete a repertoire of effector proteins into host cells that are required to hijack cellular pathways and cause disease. Despite decades of research, the molecular functions of most bacterial effectors remain unclear. To address this gap, we generated quantitative genetic interaction profiles between 36 validated and putative effectors from three evolutionarily divergent human bacterial pathogens and 4,190 yeast deletion strains. Correlating effector-generated profiles with those of yeast mutants, we recapitulated known biology for several effectors with remarkable specificity and predicted previously unknown functions for others. Biochemical and functional validation in human cells revealed a role for an uncharacterized component of the Salmonella SPI-2 translocon, SseC, in regulating maintenance of the Salmonella vacuole through interactions with components of the host retromer complex. These results exhibit the power of genetic interaction profiling to discover and dissect complex biology at the host-pathogen interface.
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Affiliation(s)
- Kristin L Patrick
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77802, USA
| | - Jason A Wojcechowskyj
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94158, USA; Quantitative Biosciences Institute (QBI), University of California, San Francisco, CA 94158, USA; J. David Gladstone Institute, San Francisco, CA 94158, USA
| | - Samantha L Bell
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77802, USA
| | - Morgan N Riba
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77802, USA
| | - Tao Jing
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA
| | - Sara Talmage
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77802, USA
| | - Pengbiao Xu
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA
| | - Ana L Cabello
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77802, USA; Department of Veterinary Pathobiology, Texas A&M College of Veterinary Medicine and Biomedical Sciences, College Station, TX 77843, USA; Norman Borlaug Center, Texas A&M University, College Station, TX 77843, USA
| | - Jiewei Xu
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94158, USA; Quantitative Biosciences Institute (QBI), University of California, San Francisco, CA 94158, USA
| | - Michael Shales
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94158, USA; Quantitative Biosciences Institute (QBI), University of California, San Francisco, CA 94158, USA
| | - David Jimenez-Morales
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94158, USA; Quantitative Biosciences Institute (QBI), University of California, San Francisco, CA 94158, USA; J. David Gladstone Institute, San Francisco, CA 94158, USA
| | - Thomas A Ficht
- Department of Veterinary Pathobiology, Texas A&M College of Veterinary Medicine and Biomedical Sciences, College Station, TX 77843, USA
| | - Paul de Figueiredo
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77802, USA; Department of Veterinary Pathobiology, Texas A&M College of Veterinary Medicine and Biomedical Sciences, College Station, TX 77843, USA; Norman Borlaug Center, Texas A&M University, College Station, TX 77843, USA
| | - James E Samuel
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77802, USA
| | - Pingwei Li
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA
| | - Nevan J Krogan
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, CA 94158, USA; Quantitative Biosciences Institute (QBI), University of California, San Francisco, CA 94158, USA; J. David Gladstone Institute, San Francisco, CA 94158, USA.
| | - Robert O Watson
- Department of Microbial Pathogenesis and Immunology, Texas A&M University Health Science Center, Bryan, TX 77802, USA.
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113
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Purushothaman LK, Ungermann C. Cargo induces retromer-mediated membrane remodeling on membranes. Mol Biol Cell 2018; 29:2709-2719. [PMID: 30188774 PMCID: PMC6249844 DOI: 10.1091/mbc.e18-06-0339] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Endosomes serve as a central sorting station of lipids and proteins that arrive via vesicular carrier from the plasma membrane and the Golgi complex. At the endosome, retromer complexes sort selected receptors and membrane proteins into tubules or vesicles that bud off the endosome. The mature endosome finally fuses with the lysosome. Retromer complexes consist of a cargo selection complex (CSC) and a membrane remodeling part (sorting nexin [SNX]-Bin/amphiphysin/Rvs [BAR], or Snx3 in yeast) and different assemblies of retromer mediate recycling of different cargoes. Due to this complexity, the exact order of events that results in carrier formation is not yet understood. Here, we reconstituted this process on giant unilamellar vesicles together with purified retromer complexes from yeast and selected cargoes. Our data reveal that the membrane remodeling activity of both Snx3 and the SNX-BAR complex is strongly reduced at low concentrations, which can be reactivated by CSC. At even lower concentrations, these complexes still associate with membranes, but only remodel membranes in the presence of their specific cargoes. Our data thus favor a simple model, where cargo functions as a specific trigger of retromer-mediated sorting on endosomes.
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Affiliation(s)
- Latha Kallur Purushothaman
- Biochemistry Section, Department of Biology/Chemistry, University of Osnabrück, 49076 Osnabrück, Germany
| | - Christian Ungermann
- Biochemistry Section, Department of Biology/Chemistry, University of Osnabrück, 49076 Osnabrück, Germany.,Center of Cellular Nanoanalytics Osnabrück (CellNanOs), University of Osnabrück, 49076 Osnabrück, Germany
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114
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Borg Distefano M, Hofstad Haugen L, Wang Y, Perdreau-Dahl H, Kjos I, Jia D, Morth JP, Neefjes J, Bakke O, Progida C. TBC1D5 controls the GTPase cycle of Rab7b. J Cell Sci 2018; 131:jcs.216630. [PMID: 30111580 DOI: 10.1242/jcs.216630] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 08/02/2018] [Indexed: 01/01/2023] Open
Abstract
Rab GTPases are key regulators of intracellular trafficking, and cycle between a GTP-bound active state and a GDP-bound inactive state. This cycle is regulated by guanine-nucleotide exchange factors (GEFs) and GTPase-activating proteins (GAPs). Several efforts have been made in connecting the correct GEFs and GAPs to their specific Rab. Here, we aimed to identify GAPs for Rab7b, the small GTPase involved in transport from late endosomes to the trans-Golgi. An siRNA screen targeting proteins containing TBC domains critical for Rab GAPs was performed and coupled to a phenotypic read-out that visualized the distribution of Rab7b. Silencing of TBC1D5 provided the strongest phenotype and this protein was subsequently validated in various in vitro and cell-based assays. TBC1D5 localizes to Rab7b-positive vesicles, interacts with Rab7b and has GAP activity towards Rab7b in vitro, which is further increased by retromer proteins. Similarly to the constitutively active mutant of Rab7b, inactivation of TBC1D5 also reduces the number of CI-MPR- and sortilin-positive vesicles. Together, the results show that TBC1D5 is a GAP for Rab7b in the control of endosomal transport to the trans-Golgi.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Marita Borg Distefano
- Department of Biosciences, Centre for Immune Regulation, University of Oslo, 0316 Oslo, Norway
| | - Linda Hofstad Haugen
- Department of Biosciences, Centre for Immune Regulation, University of Oslo, 0316 Oslo, Norway
| | - Yan Wang
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Department of Paediatrics, West China Second University Hospital, State Key Laboratory of Biotherapy, Sichuan University, Chengdu 610041, China
| | - Harmonie Perdreau-Dahl
- Norwegian Center of Molecular Medicine, Nordic EMBL Partnership, University of Oslo, 0318 Oslo, Norway
| | - Ingrid Kjos
- Department of Biosciences, Centre for Immune Regulation, University of Oslo, 0316 Oslo, Norway
| | - Da Jia
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Department of Paediatrics, West China Second University Hospital, State Key Laboratory of Biotherapy, Sichuan University, Chengdu 610041, China
| | - Jens Preben Morth
- Norwegian Center of Molecular Medicine, Nordic EMBL Partnership, University of Oslo, 0318 Oslo, Norway.,Institute for Experimental Medical Research, Oslo University Hospital, 0424 Oslo, Norway
| | - Jacques Neefjes
- Department of Cell and Chemical Biology, Leiden University Medical Center LUMC, 2300 RC Leiden, The Netherlands
| | - Oddmund Bakke
- Department of Biosciences, Centre for Immune Regulation, University of Oslo, 0316 Oslo, Norway
| | - Cinzia Progida
- Department of Biosciences, Centre for Immune Regulation, University of Oslo, 0316 Oslo, Norway
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115
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Wang J, Fedoseienko A, Chen B, Burstein E, Jia D, Billadeau DD. Endosomal receptor trafficking: Retromer and beyond. Traffic 2018; 19:578-590. [PMID: 29667289 PMCID: PMC6043395 DOI: 10.1111/tra.12574] [Citation(s) in RCA: 116] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 04/11/2018] [Accepted: 04/13/2018] [Indexed: 12/17/2022]
Abstract
The tubular endolysosomal network is a quality control system that ensures the proper delivery of internalized receptors to specific subcellular destinations in order to maintain cellular homeostasis. Although retromer was originally described in yeast as a regulator of endosome-to-Golgi receptor recycling, mammalian retromer has emerged as a central player in endosome-to-plasma membrane recycling of a variety of receptors. Over the past decade, information regarding the mechanism by which retromer facilitates receptor trafficking has emerged, as has the identification of numerous retromer-associated molecules including the WASH complex, sorting nexins (SNXs) and TBC1d5. Moreover, the recent demonstration that several SNXs can directly interact with retromer cargo to facilitate endosome-to-Golgi retrieval has provided new insight into how these receptors are trafficked in cells. The mechanism by which SNX17 cargoes are recycled out of the endosomal system was demonstrated to involve a retromer-like complex termed the retriever, which is recruited to WASH positive endosomes through an interaction with the COMMD/CCDC22/CCDC93 (CCC) complex. Lastly, the mechanisms by which bacterial and viral pathogens highjack this complex sorting machinery in order to escape the endolysosomal system or remain hidden within the cells are beginning to emerge. In this review, we will highlight recent studies that have begun to unravel the intricacies by which the retromer and associated molecules contribute to receptor trafficking and how deregulation at this sorting domain can contribute to disease or facilitate pathogen infection.
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Affiliation(s)
- Jing Wang
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Department of Paediatrics, Division of Neurology, West China Second University Hospital, State Key Laboratory of Biotherapy and Collaborative Innovation Center of Biotherapy, Sichuan University, Chengdu 610041, China
| | - Alina Fedoseienko
- Division of Oncology Research, Department of Biochemistry and Molecular Biology, and Department of Immunology, College of Medicine, Mayo Clinic, Rochester, MN 55905, USA
| | - Bayou Chen
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa 50011, USA
| | - Ezra Burstein
- Department of Internal Medicine, and Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
| | - Da Jia
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Department of Paediatrics, Division of Neurology, West China Second University Hospital, State Key Laboratory of Biotherapy and Collaborative Innovation Center of Biotherapy, Sichuan University, Chengdu 610041, China
| | - Daniel D. Billadeau
- Division of Oncology Research, Department of Biochemistry and Molecular Biology, and Department of Immunology, College of Medicine, Mayo Clinic, Rochester, MN 55905, USA
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116
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Farmer T, Naslavsky N, Caplan S. Tying trafficking to fusion and fission at the mighty mitochondria. Traffic 2018; 19:569-577. [PMID: 29663589 PMCID: PMC6043374 DOI: 10.1111/tra.12573] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 04/11/2018] [Accepted: 04/11/2018] [Indexed: 01/03/2023]
Abstract
The mitochondrion is a unique organelle that serves as the main site of ATP generation needed for energy in the cell. However, mitochondria also play essential roles in cell death through apoptosis and necrosis, as well as a variety of crucial functions related to stress regulation, autophagy, lipid synthesis and calcium storage. There is a growing appreciation that mitochondrial function is regulated by the dynamics of its membrane fusion and fission; longer, fused mitochondria are optimal for ATP generation, whereas fission of mitochondria facilitates mitophagy and cell division. Despite the significance of mitochondrial homeostasis for such crucial cellular events, the intricate regulation of mitochondrial fusion and fission is only partially understood. Until very recently, only a single mitochondrial fission protein had been identified. Moreover, only now have researchers turned to address the upstream machinery that regulates mitochondrial fusion and fission proteins. Herein, we review the known GTPases involved in mitochondrial fusion and fission, but also highlight recent studies that address the mechanisms by which these GTPases are regulated. In particular, we draw attention to a substantial new body of literature linking endocytic regulatory proteins, such as the retromer VPS35 cargo selection complex subunit, to mitochondrial homeostasis. These recent studies suggest that relationships and cross-regulation between endocytic and mitochondrial pathways may be more widespread than previously assumed.
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Affiliation(s)
- Trey Farmer
- The Department of Biochemistry and Molecular Biology, The University of Nebraska Medical Center, Omaha, Nebraska
| | - Naava Naslavsky
- The Department of Biochemistry and Molecular Biology, The University of Nebraska Medical Center, Omaha, Nebraska
| | - Steve Caplan
- The Department of Biochemistry and Molecular Biology, The University of Nebraska Medical Center, Omaha, Nebraska
- The Fred and Pamela Buffett Cancer Center, The University of Nebraska Medical Center, Omaha, Nebraska
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117
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Endosomal Retrieval of Cargo: Retromer Is Not Alone. Trends Cell Biol 2018; 28:807-822. [PMID: 30072228 DOI: 10.1016/j.tcb.2018.06.005] [Citation(s) in RCA: 92] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 06/15/2018] [Accepted: 06/22/2018] [Indexed: 11/20/2022]
Abstract
Endosomes are major protein sorting stations in cells. Endosomally localised multi-protein complexes sort integral proteins, including signaling receptors, nutrient transporters, adhesion molecules, and lysosomal hydrolase receptors, for lysosomal degradation or conversely for retrieval and subsequent recycling to various membrane compartments. Correct endosomal sorting of these proteins is essential for maintaining cellular homeostasis, with defects in endosomal sorting implicated in various human pathologies including neurodegenerative disorders. Retromer, an ancient multi-protein complex, is essential for the retrieval and recycling of hundreds of transmembrane proteins. While retromer is a major player in endosomal retrieval and recycling, several studies have recently identified retrieval mechanisms that are independent of retromer. Here, we review endosomal retrieval complexes, with a focus on recently discovered retromer-independent mechanisms.
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118
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Langemeyer L, Fröhlich F, Ungermann C. Rab GTPase Function in Endosome and Lysosome Biogenesis. Trends Cell Biol 2018; 28:957-970. [PMID: 30025982 DOI: 10.1016/j.tcb.2018.06.007] [Citation(s) in RCA: 244] [Impact Index Per Article: 40.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 06/15/2018] [Accepted: 06/25/2018] [Indexed: 10/28/2022]
Abstract
Eukaryotic cells maintain a highly organized endolysosomal system. This system regulates the protein and lipid content of the plasma membrane, it participates in the intracellular quality control machinery and is needed for the efficient removal of damaged organelles. This complex network comprises an endosomal membrane system that feeds into the lysosomes, yet also allows recycling of membrane proteins, and probably lipids. Moreover, lysosomal degradation provides the cell with macromolecules for further growth. In this review, we focus primarily on the role of the small Rab GTPases Rab5 and Rab7 as organelle markers and interactors of multiple effectors on endosomes and lysosomes and highlight their role in membrane dynamics, particularly fusion along the endolysosomal pathway.
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Affiliation(s)
- Lars Langemeyer
- Department of Biology/Chemistry, Biochemistry Section, University of Osnabrück, Barbarastrasse 13, 49076 Osnabrück, Germany
| | - Florian Fröhlich
- Department of Biology/Chemistry, Molecular Membrane Biology Group, University of Osnabrück, Barbarastrasse 13, 49076 Osnabrück, Germany; Center of Cellular Nanoanalytics of the University of Osnabrück (CellNanOs), Barbarastrasse 11, 49076 Osnabrück, Germany
| | - Christian Ungermann
- Department of Biology/Chemistry, Biochemistry Section, University of Osnabrück, Barbarastrasse 13, 49076 Osnabrück, Germany; Department of Biology/Chemistry, Molecular Membrane Biology Group, University of Osnabrück, Barbarastrasse 13, 49076 Osnabrück, Germany; Center of Cellular Nanoanalytics of the University of Osnabrück (CellNanOs), Barbarastrasse 11, 49076 Osnabrück, Germany.
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119
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Seaman MNJ, Mukadam AS, Breusegem SY. Inhibition of TBC1D5 activates Rab7a and can enhance the function of the retromer cargo-selective complex. J Cell Sci 2018; 131:jcs.217398. [PMID: 29777037 PMCID: PMC6031384 DOI: 10.1242/jcs.217398] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Accepted: 05/04/2018] [Indexed: 01/01/2023] Open
Abstract
The retromer complex is a vital component of the endosomal protein sorting machinery necessary for sorting into both the endosome-to-Golgi retrieval pathway and also the endosome-to-cell-surface recycling pathway. Retromer mediates cargo selection through a trimeric complex comprising VPS35, VPS29 and VPS26, which is recruited to endosomes by binding to Rab7a and Snx3. Retromer function is linked to two distinct neurodegenerative diseases, Parkinson's disease and Alzheimer's disease and modulating retromer function has been proposed as an avenue to explore for a putative therapy in these conditions. We hypothesised that activating Rab7a to promote the recruitment of retromer to endosomes could positively modulate its activity. Here, we show that inhibition of the GTPase activating protein TBC1D5 can enhance Rab7a activation and lead to a gain of function for retromer. Highlighted Article: Enhancement of retromer complex function through inhibition of TBC1D5, a Rab GTPase-activating protein for Rab7a, leads to a gain of function for retromer-mediated endosomal sorting.
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Affiliation(s)
- Matthew N J Seaman
- Department of Clinical Biochemistry, Cambridge Institute for Medical Research, University of Cambridge, Addenbrookes Biomedical Campus, Cambridge, CB2 0XY, UK
| | - Aamir S Mukadam
- Department of Clinical Biochemistry, Cambridge Institute for Medical Research, University of Cambridge, Addenbrookes Biomedical Campus, Cambridge, CB2 0XY, UK
| | - Sophia Y Breusegem
- Department of Clinical Biochemistry, Cambridge Institute for Medical Research, University of Cambridge, Addenbrookes Biomedical Campus, Cambridge, CB2 0XY, UK
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120
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Yong X, Hu W, Zhou X, Wang J, Burstein E, Jia D. Expression and purification of the SNX1/SNX6 complex. Protein Expr Purif 2018; 151:93-98. [PMID: 29908913 DOI: 10.1016/j.pep.2018.06.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 05/31/2018] [Accepted: 06/13/2018] [Indexed: 12/29/2022]
Abstract
The sorting nexin (SNX) family proteins play an essential role in vesicular transport, cell signaling, and membrane remodeling. The SNX members SNX1/2 and SNX5/6 form dimers, and mediate endosome-to-trans Golgi network (TGN) transport through coordinating cargo selection and membrane remodeling. It is well-known how a SNX-BAR protein forms a homodimer; however, it is less clear how a heterodimer is formed. Here a detailed expression and purification protocol of the SNX1/SNX6 complex, from both worm and human, is described. Keys to the successful protein production include co-expression of both genes, and inclusion of glycerol in the protein buffer. Solution studies suggest that SNX1 and SNX6 form a 1:1 heterodimer. The production of a large amount, high quality of the SNX1/SNX6 complex provides a basis for future biochemical and structural studies of the complex, and in vitro reconstitution of SNX1/SNX6-mediated transport.
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Affiliation(s)
- Xin Yong
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Department of Paediatrics, Drug Clinical Trial Institute, West China Second University Hospital, Sichuan University, Chengdu 610041, China
| | - Wenfeng Hu
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Department of Paediatrics, Drug Clinical Trial Institute, West China Second University Hospital, Sichuan University, Chengdu 610041, China
| | - Xue Zhou
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Department of Paediatrics, Drug Clinical Trial Institute, West China Second University Hospital, Sichuan University, Chengdu 610041, China
| | - Jing Wang
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Department of Paediatrics, Drug Clinical Trial Institute, West China Second University Hospital, Sichuan University, Chengdu 610041, China
| | - Ezra Burstein
- Department of Internal Medicine and Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Da Jia
- Key Laboratory of Birth Defects and Related Diseases of Women and Children, Department of Paediatrics, Drug Clinical Trial Institute, West China Second University Hospital, Sichuan University, Chengdu 610041, China.
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121
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Tilley FC, Gallon M, Luo C, Danson CM, Zhou J, Cullen PJ. Retromer associates with the cytoplasmic amino-terminus of polycystin-2. J Cell Sci 2018; 131:jcs.211342. [PMID: 29724910 DOI: 10.1242/jcs.211342] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Accepted: 04/26/2018] [Indexed: 12/18/2022] Open
Abstract
Autosomal dominant polycystic kidney disease (ADPKD) is the most common monogenic human disease, with around 12.5 million people affected worldwide. ADPKD results from mutations in either PKD1 or PKD2, which encode the atypical G-protein coupled receptor polycystin-1 (PC1) and the transient receptor potential channel polycystin-2 (PC2), respectively. Although altered intracellular trafficking of PC1 and PC2 is an underlying feature of ADPKD, the mechanisms which govern vesicular transport of the polycystins through the biosynthetic and endosomal membrane networks remain to be fully elucidated. Here, we describe an interaction between PC2 and retromer, a master controller for the sorting of integral membrane proteins through the endo-lysosomal network. We show that association of PC2 with retromer occurs via a region in the PC2 cytoplasmic amino-terminal domain, independently of the retromer-binding Wiskott-Aldrich syndrome and scar homologue (WASH) complex. Based on observations that retromer preferentially interacts with a trafficking population of PC2, and that ciliary levels of PC1 are reduced upon mutation of key residues required for retromer association in PC2, our data are consistent with the identification of PC2 as a retromer cargo protein.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Frances C Tilley
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol BS8 1TD, UK
| | - Matthew Gallon
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol BS8 1TD, UK
| | - Chong Luo
- Harvard Center for Polycystic Kidney Disease Research and Renal Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.,Kidney Disease Center, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310058, People's Republic of China
| | - Chris M Danson
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol BS8 1TD, UK
| | - Jing Zhou
- Harvard Center for Polycystic Kidney Disease Research and Renal Division, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Peter J Cullen
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol BS8 1TD, UK
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122
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Elwell C, Engel J. Emerging Role of Retromer in Modulating Pathogen Growth. Trends Microbiol 2018; 26:769-780. [PMID: 29703496 DOI: 10.1016/j.tim.2018.04.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 03/21/2018] [Accepted: 04/02/2018] [Indexed: 12/20/2022]
Abstract
Intracellular pathogens have developed elegant mechanisms to modulate host endosomal trafficking. The highly conserved retromer pathway has emerged as an important target of viruses and intravacuolar bacteria. Some pathogens require retromer function to survive. For others, retromer activity restricts intracellular growth; these pathogens must disrupt retromer function to survive. In this review, we discuss recent paradigm changes to the current model for retromer assembly and cargo selection. We highlight how the study of pathogen effectors has contributed to these fundamental insights, with a special focus on the biology and structure of two recently described bacterial effectors, Chlamydia trachomatis IncE and Legionella pneumophila RidL. These two pathogens employ distinct strategies to target retromer components and overcome restriction of intracellular growth imposed by retromer.
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Affiliation(s)
- Cherilyn Elwell
- Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Joanne Engel
- Department of Medicine, University of California, San Francisco, San Francisco, CA 94143, USA; Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94143, USA.
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123
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Reitz C. Retromer Dysfunction and Neurodegenerative Disease. Curr Genomics 2018; 19:279-288. [PMID: 29755290 PMCID: PMC5930449 DOI: 10.2174/1389202919666171024122809] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2015] [Revised: 08/07/2015] [Accepted: 05/25/2016] [Indexed: 11/22/2022] Open
Abstract
In recent years, genomic, animal and cell biology studies have implicated deficiencies in retromer-mediated trafficking of proteins in an increasing number of neurodegenerative diseases including Alzheimer's Disease (AD), Parkinson's Disease (PD) and Frontotemporal Lobar Degener-ation (FTLD). The retromer complex, which is highly conserved across all eukaryotes, regulates the sorting of transmembrane proteins out of endo-somes to the cell surface or to the trans-Golgi network. Within retromer, cargo selection and binding are performed by a trimer of the Vps26, Vps29 and Vps35 proteins, named the "Cargo-Selective Complex (CSC)". Sorting of cargo into tubules for distribution to the trans-Golgi network or the cell sur-face is achieved through the dimeric sorting nexin (SNX) component of retromer and accessory proteins such as the WASH complex which medi-ates the formation of discrete endosomal tubules enabling the sorting of cargo into distinct pathways through production of filamentous actin patch-es. In the present article, we review the molecular structure and function of the retromer and summarize the evidence linking retromer dysfunction to neurodegenerative disease.
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Affiliation(s)
- Christiane Reitz
- The Taub Institute for Research on Alzheimer's Disease and the Aging Brain, The Gertrude H. Sergievsky Center, Columbia University, New York, NY, USA; Department of Neurology, Columbia University, New York, NY, USA; Department of Epidemiology, Columbia University, New York, NY, USA
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124
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Tammineni P, Jeong YY, Feng T, Aikal D, Cai Q. Impaired axonal retrograde trafficking of the retromer complex augments lysosomal deficits in Alzheimer's disease neurons. Hum Mol Genet 2018; 26:4352-4366. [PMID: 28973312 DOI: 10.1093/hmg/ddx321] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 08/09/2017] [Indexed: 01/13/2023] Open
Abstract
Lysosomal proteolysis is essential for the quality control of intracellular components and the maintenance of cellular homeostasis. Lysosomal alterations have been implicated as one of the main cellular defects contributing to the onset and progression of Alzheimer's disease (AD). However, the mechanism underlying lysosomal deficits in AD remains poorly understood. Here, we reveal that lysosomal deficits are attributed to retromer dysfunction induced by altered retromer trafficking in the axon of AD-related mutant human amyloid precursor protein (hAPP) transgenic (Tg) mouse neurons. We demonstrate that retrograde transport of retromer is impaired, leading to its significant reduction in the soma and abnormal retention within late endosomes in distal axons of mutant hAPP neurons. Therefore, retromer-mediated endosome-to-Golgi retrieval of cation-independent mannose-6-phosphate receptors (CI-MPR) in the soma is disrupted in mutant hAPP neurons, causing defects in lysosome biogenesis. Such defects result in protease deficiency in lysosomes and impaired lysosomal proteolysis, as evidenced by aberrant accumulation of sequestered substrates within lysosomes. Intriguingly, enhancement of retrograde transport in mutant hAPP neurons facilitates the trafficking of axonal retromer toward the soma and thus enhances protease transport to lysosomes, thereby restoring lysosomal proteolytic activity. Taken together, our study provides new insights into the regulation of retromer trafficking through retrograde axonal transport to fulfil its function in promoting lysosome biogenesis in the soma, suggesting a potential approach for rescuing lysosomal proteolysis deficits in AD.
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Affiliation(s)
- Prasad Tammineni
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
| | - Yu Young Jeong
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
| | - Tuancheng Feng
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
| | - Daniyal Aikal
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
| | - Qian Cai
- Department of Cell Biology and Neuroscience, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA
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125
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Mechanism of inhibition of retromer transport by the bacterial effector RidL. Proc Natl Acad Sci U S A 2018; 115:E1446-E1454. [PMID: 29386389 DOI: 10.1073/pnas.1717383115] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Retrograde vesicle trafficking pathways are responsible for returning membrane-associated components from endosomes to the Golgi apparatus and the endoplasmic reticulum (ER), and they are critical for maintaining organelle identity, lipid homeostasis, and many other cellular functions. The retrograde transport pathway has emerged as an important target for intravacuolar bacterial pathogens. The opportunistic pathogen Legionella pneumophila exploits both the secretory and recycling branches of the vesicle transport pathway for intracellular bacterial proliferation. Its Dot/Icm effector RidL inhibits the activity of the retromer by directly engaging retromer components. However, the mechanism underlying such inhibition remains unknown. Here we present the crystal structure of RidL in complex with VPS29, a subunit of the retromer. Our results demonstrate that RidL binds to a highly conserved hydrophobic pocket of VPS29. This interaction is critical for endosomal recruitment of RidL and for its inhibitory effects. RidL inhibits retromer activity by direct competition, in which it occupies the VPS29-binding site of the essential retromer regulator TBC1d5. The mechanism of retromer inhibition by RidL reveals a hotspot on VPS29 critical for recognition by its regulators that is also exploited by pathogens, and provides a structural basis for the development of small molecule inhibitors against the retromer.
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126
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Jimenez-Orgaz A, Kvainickas A, Nägele H, Denner J, Eimer S, Dengjel J, Steinberg F. Control of RAB7 activity and localization through the retromer-TBC1D5 complex enables RAB7-dependent mitophagy. EMBO J 2018; 37:235-254. [PMID: 29158324 PMCID: PMC5770787 DOI: 10.15252/embj.201797128] [Citation(s) in RCA: 133] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 10/18/2017] [Accepted: 10/23/2017] [Indexed: 12/05/2022] Open
Abstract
Retromer is an endosomal multi-protein complex that organizes the endocytic recycling of a vast range of integral membrane proteins. Here, we establish an additional retromer function in controlling the activity and localization of the late endosomal small GTPase RAB7. Surprisingly, we found that RAB7 not only decorates late endosomes or lysosomes, but is also present on the endoplasmic reticulum, trans-Golgi network, and mitochondrial membranes, a localization that is maintained by retromer and the retromer-associated RAB7-specific GAP TBC1D5. In the absence of either TBC1D5 or retromer, RAB7 activity state and localization are no longer controlled and hyperactivated RAB7 expands over the entire lysosomal domain. This lysosomal accumulation of hyperactivated RAB7 results in a striking loss of RAB7 mobility and overall depletion of the inactive RAB7 pool on endomembranes. Functionally, we establish that this control of RAB7 activity is not required for the recycling of retromer-dependent cargoes, but instead enables the correct sorting of the autophagy related transmembrane protein ATG9a and autophagosome formation around damaged mitochondria during Parkin-mediated mitophagy.
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Affiliation(s)
- Ana Jimenez-Orgaz
- Center for Biological Systems Analysis (ZBSA), Faculty of Biology, Albert Ludwigs Universitaet Freiburg, Freiburg, Germany
| | - Arunas Kvainickas
- Center for Biological Systems Analysis (ZBSA), Faculty of Biology, Albert Ludwigs Universitaet Freiburg, Freiburg, Germany
| | - Heike Nägele
- Center for Biological Systems Analysis (ZBSA), Faculty of Biology, Albert Ludwigs Universitaet Freiburg, Freiburg, Germany
| | - Justin Denner
- Center for Biological Systems Analysis (ZBSA), Faculty of Biology, Albert Ludwigs Universitaet Freiburg, Freiburg, Germany
| | - Stefan Eimer
- Center for Biological Systems Analysis (ZBSA), Faculty of Biology, Albert Ludwigs Universitaet Freiburg, Freiburg, Germany
| | - Jörn Dengjel
- Department of Biology, Fribourg University, Fribourg, Switzerland
| | - Florian Steinberg
- Center for Biological Systems Analysis (ZBSA), Faculty of Biology, Albert Ludwigs Universitaet Freiburg, Freiburg, Germany
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127
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Abstract
The small GTPase Rab7 is the main regulator of membrane trafficking at late endosomes. This small GTPase regulates endosome-to-trans Golgi Network trafficking of sorting receptors, membrane fusion of late endosomes to lysosomes, and autophagosomes to lysosomes during autophagy. Rab7, like all Rab GTPases, binds downstream effectors coordinating several divergent pathways. How cells regulate these interactions and downstream functions is not well understood. Recent evidence suggests that Rab7 function can be modulated by the combination of several post-translational modifications that facilitate interactions with one effector while preventing binding to another one. In this review, we discuss recent data on how phosphorylation, palmitoylation and ubiquitination modulate the ability of this small GTPase to orchestrate membrane trafficking at the late endosomes.
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Affiliation(s)
- Graziana Modica
- Centre INRS-Institut Armand-Frappier, Institut National de la Recherche Scientifique, Laval, Québec, Canada H7V 1B7
| | - Stephane Lefrancois
- Centre INRS-Institut Armand-Frappier, Institut National de la Recherche Scientifique, Laval, Québec, Canada H7V 1B7.,Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec, Canada H3A 0C7
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128
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Podinovskaia M, Spang A. The Endosomal Network: Mediators and Regulators of Endosome Maturation. ENDOCYTOSIS AND SIGNALING 2018; 57:1-38. [DOI: 10.1007/978-3-319-96704-2_1] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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129
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Cui Y, Yang Z, Teasdale RD. The functional roles of retromer in Parkinson's disease. FEBS Lett 2017; 592:1096-1112. [DOI: 10.1002/1873-3468.12931] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2017] [Revised: 11/26/2017] [Accepted: 11/29/2017] [Indexed: 12/31/2022]
Affiliation(s)
- Yi Cui
- School of Biomedical Sciences Faculty of Medicine The University of Queensland Brisbane Australia
| | - Zhe Yang
- School of Biomedical Sciences Faculty of Medicine The University of Queensland Brisbane Australia
| | - Rohan D. Teasdale
- School of Biomedical Sciences Faculty of Medicine The University of Queensland Brisbane Australia
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130
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Seaman MNJ. Retromer and the cation-independent mannose 6-phosphate receptor-Time for a trial separation? Traffic 2017; 19:150-152. [PMID: 29135085 PMCID: PMC5814863 DOI: 10.1111/tra.12542] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 11/09/2017] [Accepted: 11/09/2017] [Indexed: 12/25/2022]
Abstract
The retromer cargo-selective complex (CSC) comprising Vps35, Vps29 and Vps26 mediates the endosome-to-Golgi retrieval of the cation-independent mannose 6-phosphate receptor (CIMPR). Or does it? Recently published data have questioned the validity of this long-established theory. Here, the evidence for and against a role for the retromer CSC in CIMPR endosome-to-Golgi retrieval is examined in the light of the new data that the SNX-BAR dimer is actually responsible for CIMPR retrieval.
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Affiliation(s)
- Matthew N J Seaman
- Cambridge Institute for Medical Research, Addenbrookes Hospital, University of Cambridge, Cambridge, UK
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131
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Molecular mechanism for the subversion of the retromer coat by the Legionella effector RidL. Proc Natl Acad Sci U S A 2017; 114:E11151-E11160. [PMID: 29229824 PMCID: PMC5748213 DOI: 10.1073/pnas.1715361115] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Deciphering microbial virulence mechanisms is of fundamental importance for the treatment of infectious diseases. Legionella pneumophila, the causative agent of Legionnaires’ pneumonia, hijacks a variety of host cell factors during intracellular growth. Herein, we uncovered the molecular mechanism by which the L. pneumophila effector RidL targets the host VPS29, a scaffolding protein of endosome-associated sorting machineries. Using X-ray crystallography, we determined the structure of RidL, both alone and in complex with retromer. We found that RidL uses a hairpin loop similar to that present in cellular ligands to interact with retromer. This sophisticated molecular mimicry allows RidL to outcompete cellular ligands for retromer binding, explaining how L. pneumophila utilizes the endosomal sorting machinery to facilitate targeting of effector proteins. Microbial pathogens employ sophisticated virulence strategies to cause infections in humans. The intracellular pathogen Legionella pneumophila encodes RidL to hijack the host scaffold protein VPS29, a component of retromer and retriever complexes critical for endosomal cargo recycling. Here, we determined the crystal structure of L. pneumophila RidL in complex with the human VPS29–VPS35 retromer subcomplex. A hairpin loop protruding from RidL inserts into a conserved pocket on VPS29 that is also used by cellular ligands, such as Tre-2/Bub2/Cdc16 domain family member 5 (TBC1D5) and VPS9-ankyrin repeat protein for VPS29 binding. Consistent with the idea of molecular mimicry in protein interactions, RidL outcompeted TBC1D5 for binding to VPS29. Furthermore, the interaction of RidL with retromer did not interfere with retromer dimerization but was essential for association of RidL with retromer-coated vacuolar and tubular endosomes. Our work thus provides structural and mechanistic evidence into how RidL is targeted to endosomal membranes.
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132
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Bärlocher K, Welin A, Hilbi H. Formation of the Legionella Replicative Compartment at the Crossroads of Retrograde Trafficking. Front Cell Infect Microbiol 2017; 7:482. [PMID: 29226112 PMCID: PMC5706426 DOI: 10.3389/fcimb.2017.00482] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 11/06/2017] [Indexed: 12/13/2022] Open
Abstract
Retrograde trafficking from the endosomal system through the Golgi apparatus back to the endoplasmic reticulum is an essential pathway in eukaryotic cells, serving to maintain organelle identity and to recycle empty cargo receptors delivered by the secretory pathway. Intracellular replication of several bacterial pathogens, including Legionella pneumophila, is restricted by the retrograde trafficking pathway. L. pneumophila employs the Icm/Dot type IV secretion system (T4SS) to form the replication-permissive Legionella-containing vacuole (LCV), which is decorated with multiple components of the retrograde trafficking machinery as well as retrograde cargo receptors. The L. pneumophila effector protein RidL is secreted by the T4SS and interferes with retrograde trafficking. Here, we review recent evidence that the LCV interacts with the retrograde trafficking pathway, discuss the possible sites of action and function of RidL in the retrograde route, and put forth the hypothesis that the LCV is an acceptor compartment of retrograde transport vesicles.
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Affiliation(s)
- Kevin Bärlocher
- Institute of Medical Microbiology, University of Zürich, Zurich, Switzerland
| | - Amanda Welin
- Institute of Medical Microbiology, University of Zürich, Zurich, Switzerland
| | - Hubert Hilbi
- Institute of Medical Microbiology, University of Zürich, Zurich, Switzerland
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133
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Abstract
Activation and inactivation of Rab GTPases by GEFs and GAPs promotes or terminates vesicle tethering to organelles, respectively. This simple model is challenged by new evidence revealing that a catalytically inactive Rab GAP promotes rather than terminates vesicle tethering at the trans-Golgi.
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Affiliation(s)
- Francis A Barr
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK.
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134
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Bärlocher K, Hutter CAJ, Swart AL, Steiner B, Welin A, Hohl M, Letourneur F, Seeger MA, Hilbi H. Structural insights into Legionella RidL-Vps29 retromer subunit interaction reveal displacement of the regulator TBC1D5. Nat Commun 2017; 8:1543. [PMID: 29146912 PMCID: PMC5691146 DOI: 10.1038/s41467-017-01512-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 09/22/2017] [Indexed: 11/09/2022] Open
Abstract
Legionella pneumophila can cause Legionnaires’ disease and replicates intracellularly in a distinct Legionella-containing vacuole (LCV). LCV formation is a complex process that involves a plethora of type IV-secreted effector proteins. The effector RidL binds the Vps29 retromer subunit, blocks retrograde vesicle trafficking, and promotes intracellular bacterial replication. Here, we reveal that the 29-kDa N-terminal domain of RidL (RidL2–281) adopts a “foot-like” fold comprising a protruding β-hairpin at its “heel”. The deletion of the β-hairpin, the exchange to Glu of Ile170 in the β-hairpin, or Leu152 in Vps29 abolishes the interaction in eukaryotic cells and in vitro. RidL2–281 or RidL displace the Rab7 GTPase-activating protein (GAP) TBC1D5 from the retromer and LCVs, respectively, and TBC1D5 promotes the intracellular growth of L. pneumophila. Thus, the hydrophobic β-hairpin of RidL is critical for binding of the L. pneumophila effector to the Vps29 retromer subunit and displacement of the regulator TBC1D5. Legionella pneumophila replicates in a Legionella-containing vacuole (LCV). Here the authors present the structure of the Legionella effector RidL N-terminal domain and reveal how RidL contributes to the subversion of retrograde trafficking by binding to the retromer coat complex subunit Vps29, which leads to a displacement of the regulator TBC1D5.
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Affiliation(s)
- Kevin Bärlocher
- Institute of Medical Microbiology, University of Zürich, Gloriastrasse 30, 8006, Zürich, Switzerland
| | - Cedric A J Hutter
- Institute of Medical Microbiology, University of Zürich, Gloriastrasse 30, 8006, Zürich, Switzerland
| | - A Leoni Swart
- Institute of Medical Microbiology, University of Zürich, Gloriastrasse 30, 8006, Zürich, Switzerland
| | - Bernhard Steiner
- Institute of Medical Microbiology, University of Zürich, Gloriastrasse 30, 8006, Zürich, Switzerland
| | - Amanda Welin
- Institute of Medical Microbiology, University of Zürich, Gloriastrasse 30, 8006, Zürich, Switzerland
| | - Michael Hohl
- Institute of Medical Microbiology, University of Zürich, Gloriastrasse 30, 8006, Zürich, Switzerland
| | - François Letourneur
- UMR5235, DIMNP, CNRS/Université Montpellier, Place Eugène Bataillon, Montpellier, 34095, cedex 5, France
| | - Markus A Seeger
- Institute of Medical Microbiology, University of Zürich, Gloriastrasse 30, 8006, Zürich, Switzerland.
| | - Hubert Hilbi
- Institute of Medical Microbiology, University of Zürich, Gloriastrasse 30, 8006, Zürich, Switzerland.
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135
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McNally KE, Faulkner R, Steinberg F, Gallon M, Ghai R, Pim D, Langton P, Pearson N, Danson CM, Nägele H, Morris LL, Singla A, Overlee BL, Heesom KJ, Sessions R, Banks L, Collins BM, Berger I, Billadeau DD, Burstein E, Cullen PJ. Retriever is a multiprotein complex for retromer-independent endosomal cargo recycling. Nat Cell Biol 2017; 19:1214-1225. [PMID: 28892079 PMCID: PMC5790113 DOI: 10.1038/ncb3610] [Citation(s) in RCA: 201] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 08/10/2017] [Indexed: 02/08/2023]
Abstract
Following endocytosis into the endosomal network, integral membrane proteins undergo sorting for lysosomal degradation or are retrieved and recycled back to the cell surface. Here we describe the discovery of an ancient and conserved multiprotein complex that orchestrates cargo retrieval and recycling and, importantly, is biochemically and functionally distinct from the established retromer pathway. We have called this complex 'retriever'; it is a heterotrimer composed of DSCR3, C16orf62 and VPS29, and bears striking similarity to retromer. We establish that retriever associates with the cargo adaptor sorting nexin 17 (SNX17) and couples to CCC (CCDC93, CCDC22, COMMD) and WASH complexes to prevent lysosomal degradation and promote cell surface recycling of α5β1 integrin. Through quantitative proteomic analysis, we identify over 120 cell surface proteins, including numerous integrins, signalling receptors and solute transporters, that require SNX17-retriever to maintain their surface levels. Our identification of retriever establishes a major endosomal retrieval and recycling pathway.
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Affiliation(s)
- Kerrie E McNally
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol BS8 1TD, UK
| | - Rebecca Faulkner
- Department of Internal Medicine and Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
| | - Florian Steinberg
- Center for Biological Systems Analysis, Albert Ludwigs Universitaet Freiburg, 79104 Freiburg, Germany
| | - Matthew Gallon
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol BS8 1TD, UK
| | - Rajesh Ghai
- Institute for Molecular Bioscience, the University of Queensland, St. Lucia, Queensland 4072, Australia
| | - David Pim
- International Centre for Genetic Engineering and Biotechnology, Padriciano 99, I-34149 Trieste, Italy
| | - Paul Langton
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol BS8 1TD, UK
| | - Neil Pearson
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol BS8 1TD, UK
| | - Chris M Danson
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol BS8 1TD, UK
| | - Heike Nägele
- Center for Biological Systems Analysis, Albert Ludwigs Universitaet Freiburg, 79104 Freiburg, Germany
| | - Lindsey L Morris
- Department of Internal Medicine and Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
| | - Amika Singla
- Department of Internal Medicine and Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
| | - Brittany L Overlee
- Department of Biochemistry and Molecular Biology, and Department of Immunology, Mayo Clinic, Rochester, Minnesota 55905, USA
| | - Kate J Heesom
- Proteomics Facility, School of Biochemistry, University of Bristol, Bristol BS8 1TD, UK
| | - Richard Sessions
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol BS8 1TD, UK
| | - Lawrence Banks
- International Centre for Genetic Engineering and Biotechnology, Padriciano 99, I-34149 Trieste, Italy
| | - Brett M Collins
- Institute for Molecular Bioscience, the University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Imre Berger
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol BS8 1TD, UK
| | - Daniel D Billadeau
- Department of Biochemistry and Molecular Biology, and Department of Immunology, Mayo Clinic, Rochester, Minnesota 55905, USA
| | - Ezra Burstein
- Department of Internal Medicine and Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
| | - Peter J Cullen
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol BS8 1TD, UK
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136
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Kvainickas A, Jimenez-Orgaz A, Nägele H, Hu Z, Dengjel J, Steinberg F. Cargo-selective SNX-BAR proteins mediate retromer trimer independent retrograde transport. J Cell Biol 2017; 216:3677-3693. [PMID: 28935632 PMCID: PMC5674888 DOI: 10.1083/jcb.201702137] [Citation(s) in RCA: 121] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 07/10/2017] [Accepted: 08/01/2017] [Indexed: 12/11/2022] Open
Abstract
Kvainickas et al. show that the retromer cargo CI-MPR does not recycle from endosomes to the trans-Golgi network through interactions with the core retromer trimer. Instead, CI-MPR depends on cargo-selective SNX-BAR proteins, which function independently of the core retromer trimer. The retromer complex, which recycles the cation-independent mannose 6-phosphate receptor (CI-MPR) from endosomes to the trans-Golgi network (TGN), is thought to consist of a cargo-selective VPS26–VPS29–VPS35 trimer and a membrane-deforming subunit of sorting nexin (SNX)–Bin, Amphyphysin, and Rvs (BAR; SNX-BAR) proteins. In this study, we demonstrate that heterodimers of the SNX-BAR proteins, SNX1, SNX2, SNX5, and SNX6, are the cargo-selective elements that mediate the retrograde transport of CI-MPR from endosomes to the TGN independently of the core retromer trimer. Using quantitative proteomics, we also identify the IGF1R, among more potential cargo, as another SNX5 and SNX6 binding receptor that recycles through SNX-BAR heterodimers, but not via the retromer trimer, in a ligand- and activation-dependent manner. Overall, our data redefine the mechanics of retromer-based sorting and call into question whether retromer indeed functions as a complex of SNX-BAR proteins and the VPS26–VPS29–VPS35 trimer.
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Affiliation(s)
- Arunas Kvainickas
- Center for Biological Systems Analysis, Albert Ludwigs Universitaet Freiburg, Freiburg, Germany.,Faculty of Biology, Albert Ludwigs Universitaet Freiburg, Freiburg, Germany
| | - Ana Jimenez-Orgaz
- Center for Biological Systems Analysis, Albert Ludwigs Universitaet Freiburg, Freiburg, Germany.,Faculty of Biology, Albert Ludwigs Universitaet Freiburg, Freiburg, Germany
| | - Heike Nägele
- Center for Biological Systems Analysis, Albert Ludwigs Universitaet Freiburg, Freiburg, Germany
| | - Zehan Hu
- Department of Biology, Fribourg University, Fribourg, Switzerland
| | - Jörn Dengjel
- Department of Biology, Fribourg University, Fribourg, Switzerland
| | - Florian Steinberg
- Center for Biological Systems Analysis, Albert Ludwigs Universitaet Freiburg, Freiburg, Germany
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137
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Zheng H, Guo Z, Xi Y, Yuan M, Lin Y, Wu C, Abubakar YS, Dou X, Li G, Wang Z, Zheng W, Zhou J. Sorting nexin (MoVps17) is required for fungal development and plant infection by regulating endosome dynamics in the rice blast fungus. Environ Microbiol 2017; 19:4301-4317. [PMID: 28836715 DOI: 10.1111/1462-2920.13896] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 08/16/2017] [Accepted: 08/17/2017] [Indexed: 02/05/2023]
Abstract
Vps17 is a sorting nexin (SNX) and a component of the retromer, a protein complex mediating retrograde vesicle transport between endosomes and the trans-Golgi network. However, its role in the development and pathogenicity of filamentous fungi such as the rice blast fungus (Magnaporthe oryzae) remains unclear. We investigate the functional relationship between the SNX and the cargo-selective complex (CSC) of the fungal retromer by genetic analysis, live cell imaging and immunological assay. Our data show that the MoVps17 null mutation causes defects in growth, development and pathogenicity in M. oryzae. MoVps17 is localized to endosomes depending on the activity of phosphatidylinositol 3-kinase (PI3K), a key enzyme for fungal development and infection. Both PX and BAR domains of MoVps17 are essential for its endosomal localization and function. Furthermore, our yeast two-hybrid assays show that MoVps17 and MoVps5 can interact. Lastly, live cell imaging suggests that MoVps17 can regulate early endosome fusion and budding as well as endocytosis. Taken together, our results suggest that MoVps17 specifically functions as a retromer component with CSC and also plays a distinct role in the regulation of endosome dynamics during fungal development and plant infection.
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Affiliation(s)
- Huawei Zheng
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Zhongkun Guo
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Yang Xi
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Mingyue Yuan
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Yahong Lin
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Congxian Wu
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Yakubu Saddeeq Abubakar
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Xianying Dou
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Guangpu Li
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, USA
| | - Zonghua Wang
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, China.,College of Ocean Science, Minjiang University, Fuzhou 350108, China
| | - Wenhui Zheng
- Key Laboratory of Biopesticides and Chemical Biology, Ministry of Education, Fujian Agriculture and Forestry University, Fuzhou, Fujian 350002, China
| | - Jie Zhou
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou, China
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138
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The Dopamine Transporter Recycles via a Retromer-Dependent Postendocytic Mechanism: Tracking Studies Using a Novel Fluorophore-Coupling Approach. J Neurosci 2017; 37:9438-9452. [PMID: 28847807 DOI: 10.1523/jneurosci.3885-16.2017] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 07/17/2017] [Accepted: 08/19/2017] [Indexed: 01/28/2023] Open
Abstract
Presynaptic reuptake, mediated by the dopamine (DA) transporter (DAT), terminates DAergic neurotransmission and constrains extracellular DA levels. Addictive and therapeutic psychostimulants inhibit DA reuptake and multiple DAT coding variants have been reported in patients with neuropsychiatric disorders. These findings underscore that DAT is critical for DA neurotransmission and homeostasis. DAT surface availability is regulated acutely by endocytic trafficking, and considerable effort has been directed toward understanding mechanisms that govern DAT's plasma membrane expression and postendocytic fate. Multiple studies have demonstrated DAT endocytic recycling and enhanced surface delivery in response to various stimuli. Paradoxically, imaging studies have not detected DAT targeting to classic recycling endosomes, suggesting that internalized DAT targets to either degradation or an undefined recycling compartment. Here, we leveraged PRIME (PRobe Incorporation Mediated by Enzyme) labeling to couple surface DAT directly to fluorophore, and tracked DAT's postendocytic itinerary in immortalized mesencephalic cells. Following internalization, DAT robustly targeted to retromer-positive endosomes, and DAT/retromer colocalization was observed in male mouse dopaminergic somatodendritic and terminal regions. Short hairpin RNA-mediated Vps35 knockdown revealed that DAT endocytic recycling requires intact retromer. DAT also targeted rab7-positive endosomes with slow, linear kinetics that were unaffected by either accelerating DAT internalization or binding a high-affinity cocaine analog. However, cocaine increased DAT exit from retromer-positive endosomes significantly. Finally, we found that the DAT carboxy-terminal PDZ-binding motif was required for DAT recycling and exit from retromer. These results define the DAT recycling mechanism and provide a unifying explanation for previous, seemingly disparate, DAT endocytic trafficking findings.SIGNIFICANCE STATEMENT The neuronal dopamine (DA) transporter (DAT) recaptures released DA and modulates DAergic neurotransmission, and a number of DAT coding variants have been reported in several DA-related disorders, including infantile parkinsonism, attention-deficit/hyperactivity disorder and autism spectrum disorder. DAT is also competitively inhibited by psychostimulants with high abuse potential. Therefore, mechanisms that acutely affect DAT availability will likely exert significant impact on both normal and pathological DAergic homeostasis. Here, we explore the cellular mechanisms that acutely control DAT surface expression. Our results reveal the intracellular mechanisms that mediate DAT endocytic recycling following constitutive and regulated internalization. In addition to shedding light on this critical process, these findings resolve conflict among multiple, seemingly disparate, previous reports on DAT's postendocytic fate.
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139
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Sauvageau E, McCormick PJ, Lefrancois S. In vivo monitoring of the recruitment and activation of AP-1 by Arf1. Sci Rep 2017; 7:7148. [PMID: 28769048 PMCID: PMC5540999 DOI: 10.1038/s41598-017-07493-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 06/27/2017] [Indexed: 11/16/2022] Open
Abstract
AP-1 is a clathrin adaptor recruited to the trans-Golgi Network where it can interact with specific signals found in the cytosolic tail of cargo proteins to incorporate them into clathrin-coated vesicles for trafficking. The small G protein Arf1 regulates the spatiotemporal recruitment of AP-1 and also drives a conformational change favoring an interaction with cargo proteins. A recent crystal structure and in vitro experiments highlighted potential residues mediating the AP-1/Arf1 interaction and the unlocking of the complex. We have used bioluminescence resonance energy transfer (BRET) to study the Arf1/AP-1 interaction and AP-1 conformational changes in vivo. We identified novel residues required for this interaction in addition to those predicted in the crystal structure. We also studied the conformational changes in AP-1 driven by Arf1 in live cells and found that opening of the complex is prerequisite for oligomerization. Using Arf1 knockout cells generated by CRISPR/Cas9, we demonstrated that residue 172 in Arf1 is necessary for AP-1 activation and is required for the efficient sorting of the lysosomal protein prosaposin. We have used BRET to study the in vivo activation of AP-1. The advantages of BRET include expressing full-length proteins in their native environment that have been fully post-translationally modified.
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Affiliation(s)
| | - Peter J McCormick
- Faculty of Health and Medical Sciences, School of Veterinary Medicine, University of Surrey, Guildford, GU27XH, UK
| | - Stephane Lefrancois
- Centre INRS-Institut Armand-Frappier, INRS, Laval, Canada, H7V 1B7. .,Department of Anatomy and Cell Biology, McGill University, Montreal, Canada, H3A 2B2.
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140
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Jules F, Sauvageau E, Dumaresq-Doiron K, Mazzaferri J, Haug-Kröper M, Fluhrer R, Costantino S, Lefrancois S. CLN5 is cleaved by members of the SPP/SPPL family to produce a mature soluble protein. Exp Cell Res 2017; 357:40-50. [PMID: 28442266 DOI: 10.1016/j.yexcr.2017.04.024] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 04/19/2017] [Accepted: 04/21/2017] [Indexed: 11/30/2022]
Abstract
The Neuronal ceroid lipofuscinoses (NCLs) are a group of recessive disorders of childhood with overlapping symptoms including vision loss, ataxia, cognitive regression and premature death. 14 different genes have been linked to NCLs (CLN1-CLN14), but the functions of the proteins encoded by the majority of these genes have not been fully elucidated. Mutations in the CLN5 gene are responsible for the Finnish variant late-infantile form of NCL (Finnish vLINCL). CLN5 is translated as a 407 amino acid transmembrane domain containing protein that is heavily glycosylated, and subsequently cleaved into a mature soluble protein. Functionally, CLN5 is implicated in the recruitment of the retromer complex to endosomes, which is required to sort the lysosomal sorting receptors from endosomes to the trans-Golgi network. The mechanism that processes CLN5 into a mature soluble protein is currently not known. Herein, we demonstrate that CLN5 is initially translated as a type II transmembrane protein and subsequently cleaved by SPPL3, a member of the SPP/SPPL intramembrane protease family, into a mature soluble protein consisting of residues 93-407. The remaining N-terminal fragment is then cleaved by SPPL3 and SPPL2b and degraded in the proteasome. This work further characterizes the biology of CLN5 in the hopes of identifying a novel therapeutic strategy for affected children.
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Affiliation(s)
- Felix Jules
- Centre INRS-Institut Armand-Frappier, INRS, Laval, Canada H7V 1B7
| | | | | | - Javier Mazzaferri
- Centre de Recherche de l'Hôpital Maisonneuve-Rosemont, Montréal, Canada H1T 2M4
| | - Martina Haug-Kröper
- Biomedical Center (BMC), Institute for Metabolic Biochemistry, Ludwig-Maximilians University Munich, Munich, Germany
| | - Regina Fluhrer
- Biomedical Center (BMC), Institute for Metabolic Biochemistry, Ludwig-Maximilians University Munich, Munich, Germany; DZNE - German Center for Neurodegenerative Diseases, Munich, Germany
| | - Santiago Costantino
- Département d'Ophtalmologie et Institut de Génie Biomédical, Université de Montréal, Montréal, Canada H3T 1J4; Centre de Recherche de l'Hôpital Maisonneuve-Rosemont, Montréal, Canada H1T 2M4
| | - Stephane Lefrancois
- Centre INRS-Institut Armand-Frappier, INRS, Laval, Canada H7V 1B7; Department of Anatomy and Cell Biology, McGill University, Montreal, Canada H3A 2B2.
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141
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Abubakar YS, Zheng W, Olsson S, Zhou J. Updated Insight into the Physiological and Pathological Roles of the Retromer Complex. Int J Mol Sci 2017; 18:ijms18081601. [PMID: 28757549 PMCID: PMC5577995 DOI: 10.3390/ijms18081601] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 07/20/2017] [Accepted: 07/21/2017] [Indexed: 12/13/2022] Open
Abstract
Retromer complexes mediate protein trafficking from the endosomes to the trans-Golgi network (TGN) or through direct recycling to the plasma membrane. In yeast, they consist of a conserved trimer of the cargo selective complex (CSC), Vps26-Vps35-Vps29 and a dimer of sorting nexins (SNXs), Vps5-Vps17. In mammals, the CSC interacts with different kinds of SNX proteins in addition to the mammalian homologues of Vps5 and Vps17, which further diversifies retromer functions. The retromer complex plays important roles in many cellular processes including restriction of invading pathogens. In this review, we summarize some recent developments in our understanding of the physiological and pathological functions of the retromer complex.
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Affiliation(s)
- Yakubu Saddeeq Abubakar
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Wenhui Zheng
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
- College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Stefan Olsson
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
| | - Jie Zhou
- State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops, College of Life Science, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
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142
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Sun Q, Yong X, Sun X, Yang F, Dai Z, Gong Y, Zhou L, Zhang X, Niu D, Dai L, Liu JJ, Jia D. Structural and functional insights into sorting nexin 5/6 interaction with bacterial effector IncE. Signal Transduct Target Ther 2017; 2:17030. [PMID: 29263922 PMCID: PMC5661634 DOI: 10.1038/sigtrans.2017.30] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 04/11/2017] [Accepted: 04/27/2017] [Indexed: 02/05/2023] Open
Abstract
The endosomal trafficking pathways are essential for many cellular activities. They are also important targets by many intracellular pathogens. Key regulators of the endosomal trafficking include the retromer complex and sorting nexins (SNXs). Chlamydia trachomatis effector protein IncE directly targets the retromer components SNX5 and SNX6 and suppresses retromer-mediated transport, but the exact mechanism has remained unclear. We present the crystal structure of the PX domain of SNX5 in complex with IncE, showing that IncE binds to a highly conserved hydrophobic groove of SNX5. The unique helical hairpin of SNX5/6 is essential for binding, explaining the specificity of SNX5/6 for IncE. The SNX5/6–IncE interaction is required for cellular localization of IncE and its inhibitory function. Mechanistically, IncE inhibits the association of CI-MPR cargo with retromer-containing endosomal subdomains. Our study provides new insights into the regulation of retromer-mediated transport and illustrates the intricate competition between host and pathogens in controlling cellular trafficking.
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Affiliation(s)
- Qingxiang Sun
- Department of Pathology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and Collaborative Innovation Center of Biotherapy, Chengdu, China
| | - Xin Yong
- Department of Pathology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and Collaborative Innovation Center of Biotherapy, Chengdu, China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children of MOE, Department of Paediatrics, West China Second University Hospital, Sichuan University, Chengdu, China
| | - Xiaodong Sun
- Department of Pharmacology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, China
| | - Fan Yang
- Department of Pathology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and Collaborative Innovation Center of Biotherapy, Chengdu, China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children of MOE, Department of Paediatrics, West China Second University Hospital, Sichuan University, Chengdu, China
| | - Zhonghua Dai
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Yanqiu Gong
- Department of Pathology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and Collaborative Innovation Center of Biotherapy, Chengdu, China
| | - Liming Zhou
- Department of Pharmacology, West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, China
| | - Xia Zhang
- Department of Pathology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and Collaborative Innovation Center of Biotherapy, Chengdu, China
| | - Dawen Niu
- Department of Pathology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and Collaborative Innovation Center of Biotherapy, Chengdu, China
| | - Lunzhi Dai
- Department of Pathology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and Collaborative Innovation Center of Biotherapy, Chengdu, China
| | - Jia-Jia Liu
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China
| | - Da Jia
- Department of Pathology, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and Collaborative Innovation Center of Biotherapy, Chengdu, China.,Key Laboratory of Birth Defects and Related Diseases of Women and Children of MOE, Department of Paediatrics, West China Second University Hospital, Sichuan University, Chengdu, China
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143
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Modica G, Skorobogata O, Sauvageau E, Vissa A, Yip CM, Kim PK, Wurtele H, Lefrancois S. Rab7 palmitoylation is required for efficient endosome-to-TGN trafficking. J Cell Sci 2017; 130:2579-2590. [PMID: 28600323 DOI: 10.1242/jcs.199729] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 06/06/2017] [Indexed: 12/14/2022] Open
Abstract
Retromer is a multimeric protein complex that mediates endosome-to-trans-Golgi network (TGN) and endosome-to-plasma membrane trafficking of integral membrane proteins. Dysfunction of this complex has been linked to Alzheimer's disease and Parkinson's disease. The recruitment of retromer to endosomes is regulated by Rab7 (also known as RAB7A) to coordinate endosome-to-TGN trafficking of cargo receptor complexes. Rab7 is also required for the degradation of internalized integral membrane proteins, such as the epidermal growth factor receptor (EGFR). We found that Rab7 is palmitoylated and that this modification is not required for membrane anchoring. Palmitoylated Rab7 colocalizes efficiently with and has a higher propensity to interact with retromer than nonpalmitoylatable Rab7. Rescue of Rab7 knockout cells by expressing wild-type Rab7 restores efficient endosome-to-TGN trafficking, while rescue with nonpalmitoylatable Rab7 does not. Interestingly, Rab7 palmitoylation does not appear to be required for the degradation of EGFR or for its interaction with its effector, Rab-interacting lysosomal protein (RILP). Overall, our results indicate that Rab7 palmitoylation is required for the spatiotemporal recruitment of retromer and efficient endosome-to-TGN trafficking of the lysosomal sorting receptors.
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Affiliation(s)
- Graziana Modica
- Centre INRS-Institut Armand-Frappier, Institut National de la Recherche Scientifique, Laval, Québec H7V 1B7, Canada
| | - Olga Skorobogata
- Centre INRS-Institut Armand-Frappier, Institut National de la Recherche Scientifique, Laval, Québec H7V 1B7, Canada
| | - Etienne Sauvageau
- Centre INRS-Institut Armand-Frappier, Institut National de la Recherche Scientifique, Laval, Québec H7V 1B7, Canada
| | - Adriano Vissa
- Program in Cell Biology, The Hospital for Sick Children, Toronto, Ontario M5G 1X8, Canada.,Department of Biochemistry, University of Toronto, Toronto M5G 1X8, Canada.,Institute of Biomaterials & Biomedical Engineering and Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario M5S 3E5, Canada
| | - Christopher M Yip
- Department of Biochemistry, University of Toronto, Toronto M5G 1X8, Canada.,Institute of Biomaterials & Biomedical Engineering and Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, Ontario M5S 3E5, Canada
| | - Peter K Kim
- Program in Cell Biology, The Hospital for Sick Children, Toronto, Ontario M5G 1X8, Canada.,Department of Biochemistry, University of Toronto, Toronto M5G 1X8, Canada
| | - Hugo Wurtele
- Centre de recherche de l'Hôpital Maisonneuve-Rosemont, Montréal H1T 2M4, Canada.,Département de Médecine, Université de Montréal, Montréal, Québec H3C 3J7, Canada
| | - Stephane Lefrancois
- Centre INRS-Institut Armand-Frappier, Institut National de la Recherche Scientifique, Laval, Québec H7V 1B7, Canada .,Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec H3A 0C7, Canada
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144
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Roy S, Leidal AM, Ye J, Ronen SM, Debnath J. Autophagy-Dependent Shuttling of TBC1D5 Controls Plasma Membrane Translocation of GLUT1 and Glucose Uptake. Mol Cell 2017; 67:84-95.e5. [PMID: 28602638 DOI: 10.1016/j.molcel.2017.05.020] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 04/07/2017] [Accepted: 05/19/2017] [Indexed: 01/16/2023]
Abstract
Autophagy traditionally sustains metabolism in stressed cells by promoting intracellular catabolism and nutrient recycling. Here, we demonstrate that in response to stresses requiring increased glycolytic demand, the core autophagy machinery also facilitates glucose uptake and glycolytic flux by promoting cell surface expression of the glucose transporter GLUT1/Slc2a1. During metabolic stress, LC3+ autophagic compartments bind and sequester the RabGAP protein TBC1D5 away from its inhibitory interactions with the retromer complex, thereby enabling retromer recruitment to endosome membranes and GLUT1 plasma membrane translocation. In contrast, TBC1D5 inhibitory interactions with the retromer are maintained in autophagy-deficient cells, leading to GLUT1 mis-sorting into endolysosomal compartments. Furthermore, TBC1D5 depletion in autophagy-deficient cells rescues retromer recruitment to endosomal membranes and GLUT1 surface recycling. Hence, TBC1D5 shuttling to autophagosomes during metabolic stress facilitates retromer-dependent GLUT1 trafficking. Overall, our results illuminate key interconnections between the autophagy and endosomal pathways dictating GLUT1 trafficking and extracellular nutrient uptake.
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Affiliation(s)
- Srirupa Roy
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Andrew M Leidal
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Jordan Ye
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Sabrina M Ronen
- Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Jayanta Debnath
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143, USA.
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145
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Buckley CM, King JS. Drinking problems: mechanisms of macropinosome formation and maturation. FEBS J 2017; 284:3778-3790. [DOI: 10.1111/febs.14115] [Citation(s) in RCA: 93] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Revised: 04/25/2017] [Accepted: 05/17/2017] [Indexed: 11/30/2022]
Affiliation(s)
- Catherine M. Buckley
- Department of Biomedical Sciences Centre for Membrane Interactions and Dynamics University of Sheffield UK
- Bateson Centre University of Sheffield UK
| | - Jason S. King
- Department of Biomedical Sciences Centre for Membrane Interactions and Dynamics University of Sheffield UK
- Bateson Centre University of Sheffield UK
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146
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McMillan KJ, Gallon M, Jellett AP, Clairfeuille T, Tilley FC, McGough I, Danson CM, Heesom KJ, Wilkinson KA, Collins BM, Cullen PJ. Atypical parkinsonism-associated retromer mutant alters endosomal sorting of specific cargo proteins. J Cell Biol 2017; 214:389-99. [PMID: 27528657 PMCID: PMC4987296 DOI: 10.1083/jcb.201604057] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Accepted: 07/22/2016] [Indexed: 01/12/2023] Open
Abstract
Mutations in the retromer complex, which is involved in sorting integral membrane proteins from endosomes to cellular compartments, are associated with atypical parkinsonism, but how these mutations affect retromer function remains unclear. Through a quantitative proteomic analysis of the retromer interactome, McMillan et al. reveal a new mechanism for perturbed endosomal sorting in parkinsonism. The retromer complex acts as a scaffold for endosomal protein complexes that sort integral membrane proteins to various cellular destinations. The retromer complex is a heterotrimer of VPS29, VPS35, and VPS26. Two of these paralogues, VPS26A and VPS26B, are expressed in humans. Retromer dysfunction is associated with neurodegenerative disease, and recently, three VPS26A mutations (p.K93E, p.M112V, and p.K297X) were discovered to be associated with atypical parkinsonism. Here, we apply quantitative proteomics to provide a detailed description of the retromer interactome. By establishing a comparative proteomic methodology, we identify how this interactome is perturbed in atypical parkinsonism-associated VPS26A mutants. In particular, we describe a selective defect in the association of VPS26A (p.K297X) with the SNX27 cargo adaptor. By showing how a retromer mutant leads to altered endosomal sorting of specific PDZ ligand–containing cargo proteins, we reveal a new mechanism for perturbed endosomal cargo sorting in atypical parkinsonism.
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Affiliation(s)
- Kirsty J McMillan
- School of Biochemistry, University of Bristol, Bristol BS8 1TD, England, UK
| | - Matthew Gallon
- School of Biochemistry, University of Bristol, Bristol BS8 1TD, England, UK
| | - Adam P Jellett
- School of Biochemistry, University of Bristol, Bristol BS8 1TD, England, UK
| | - Thomas Clairfeuille
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Frances C Tilley
- School of Biochemistry, University of Bristol, Bristol BS8 1TD, England, UK
| | - Ian McGough
- School of Biochemistry, University of Bristol, Bristol BS8 1TD, England, UK
| | - Chris M Danson
- School of Biochemistry, University of Bristol, Bristol BS8 1TD, England, UK
| | - Kate J Heesom
- Proteomics Facility, School of Biochemistry, University of Bristol, Bristol BS8 1TD, England, UK
| | - Kevin A Wilkinson
- School of Biochemistry, University of Bristol, Bristol BS8 1TD, England, UK
| | - Brett M Collins
- Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Peter J Cullen
- School of Biochemistry, University of Bristol, Bristol BS8 1TD, England, UK
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147
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Fleming DS, Weigend S, Simianer H, Weigend A, Rothschild M, Schmidt C, Ashwell C, Persia M, Reecy J, Lamont SJ. Genomic Comparison of Indigenous African and Northern European Chickens Reveals Putative Mechanisms of Stress Tolerance Related to Environmental Selection Pressure. G3 (BETHESDA, MD.) 2017; 7:1525-1537. [PMID: 28341699 PMCID: PMC5427493 DOI: 10.1534/g3.117.041228] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Accepted: 03/15/2017] [Indexed: 01/11/2023]
Abstract
Global climate change is increasing the magnitude of environmental stressors, such as temperature, pathogens, and drought, that limit the survivability and sustainability of livestock production. Poultry production and its expansion is dependent upon robust animals that are able to cope with stressors in multiple environments. Understanding the genetic strategies that indigenous, noncommercial breeds have evolved to survive in their environment could help to elucidate molecular mechanisms underlying biological traits of environmental adaptation. We examined poultry from diverse breeds and climates of Africa and Northern Europe for selection signatures that have allowed them to adapt to their indigenous environments. Selection signatures were studied using a combination of population genomic methods that employed FST , integrated haplotype score (iHS), and runs of homozygosity (ROH) procedures. All the analyses indicated differences in environment as a driver of selective pressure in both groups of populations. The analyses revealed unique differences in the genomic regions under selection pressure from the environment for each population. The African chickens showed stronger selection toward stress signaling and angiogenesis, while the Northern European chickens showed more selection pressure toward processes related to energy homeostasis. The results suggest that chromosomes 2 and 27 are the most diverged between populations and the most selected upon within the African (chromosome 27) and Northern European (chromosome 2) birds. Examination of the divergent populations has provided new insight into genes under possible selection related to tolerance of a population's indigenous environment that may be baselines for examining the genomic contribution to tolerance adaptions.
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Affiliation(s)
| | | | | | | | | | | | - Chris Ashwell
- North Carolina State University, Raleigh, North Carolina 27695
| | - Mike Persia
- Virginia Tech University, Blacksburg, Virginia 24061
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148
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Lin X, Zhang J, Chen L, Chen Y, Xu X, Hong W, Wang T. Tyrosine phosphorylation of Rab7 by Src kinase. Cell Signal 2017; 35:84-94. [PMID: 28336235 DOI: 10.1016/j.cellsig.2017.03.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Revised: 02/28/2017] [Accepted: 03/14/2017] [Indexed: 12/15/2022]
Abstract
The small molecular weight GTPase Rab7 is a key regulator for late endosomal/lysosomal membrane trafficking, it was known that Rab7 is phosphorylated, but the corresponding kinase and the functional regulation of Rab7 phosphorylation remain unclear. We provide evidence here that Rab7 is a substrate of Src kinase, and is tyrosine-phosphorylated by Src, withY183 residue of Rab7 being the optimal phosphorylation site for Src. Further investigations demonstrated that the tyrosine phosphorylation of Rab7 depends on the guanine nucleotide binding activity of Rab7 and the activity of Src kinase. The tyrosine phosphorylation of Rab7 is physiologically induced by EGF, and impairs the interaction of Rab7 with RILP, consequently inhibiting EGFR degradation and sustaining Akt signaling. These results suggest that the tyrosine phosphorylation of Rab7 may be involved in coordinating membrane trafficking and cell signaling.
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Affiliation(s)
- Xiaosi Lin
- School of Pharmaceutical Sciences, State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Fujian 361005, China
| | - Jiaming Zhang
- School of Pharmaceutical Sciences, State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Fujian 361005, China
| | - Lingqiu Chen
- School of Pharmaceutical Sciences, State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Fujian 361005, China
| | - Yongjun Chen
- School of Pharmaceutical Sciences, State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Fujian 361005, China
| | - Xiaohui Xu
- School of Pharmaceutical Sciences, State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Fujian 361005, China
| | - Wanjin Hong
- School of Pharmaceutical Sciences, State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Fujian 361005, China; Institute of Molecular and Cell Biology, A STAR(Agency of Science, Technology and Research), 61 Biopolis Drive, Singapore 138673, Singapore
| | - Tuanlao Wang
- School of Pharmaceutical Sciences, State Key Laboratory of Cellular Stress Biology, Fujian Provincial Key Laboratory of Innovative Drug Target Research, Xiamen University, Fujian 361005, China.
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149
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Charcot Marie Tooth 2B Peripheral Sensory Neuropathy: How Rab7 Mutations Impact NGF Signaling? Int J Mol Sci 2017; 18:ijms18020324. [PMID: 28165391 PMCID: PMC5343860 DOI: 10.3390/ijms18020324] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Revised: 01/10/2017] [Accepted: 01/15/2017] [Indexed: 12/12/2022] Open
Abstract
Charcot-Marie-Tooth 2B peripheral sensory neuropathy (CMT2B) is a debilitating autosomal dominant hereditary sensory neuropathy. Patients with this disease lose pain sensation and frequently need amputation. Axonal dysfunction and degeneration of peripheral sensory neurons is a major clinical manifestation of CMT2B. However, the cellular and molecular pathogenic mechanisms remain undefined. CMT2B is caused by missense point mutations (L129F, K157N, N161T/I, V162M) in Rab7 GTPase. Strong evidence suggests that the Rab7 mutation(s) enhances the cellular levels of activated Rab7 proteins, thus resulting in increased lysosomal activity and autophagy. As a consequence, trafficking and signaling of neurotrophic factors such as nerve growth factor (NGF) in the long axons of peripheral sensory neurons are particularly vulnerable to premature degradation. A “gain of toxicity” model has, thus, been proposed based on these observations. However, studies of fly photo-sensory neurons indicate that the Rab7 mutation(s) causes a “loss of function”, resulting in haploinsufficiency. In the review, we summarize experimental evidence for both hypotheses. We argue that better models (rodent animals and human neurons) of CMT2B are needed to precisely define the disease mechanisms.
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150
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Purushothaman LK, Arlt H, Kuhlee A, Raunser S, Ungermann C. Retromer-driven membrane tubulation separates endosomal recycling from Rab7/Ypt7-dependent fusion. Mol Biol Cell 2017; 28:783-791. [PMID: 28100638 PMCID: PMC5349785 DOI: 10.1091/mbc.e16-08-0582] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Revised: 12/21/2016] [Accepted: 01/10/2017] [Indexed: 12/31/2022] Open
Abstract
How does a Rab function in both recycling and fusion? An endosomal subcomplex of the SNX-BAR retromer can bind to Ypt7 and compete with the HOPS complex. Assembly of the full retromer then results in displacement of Ypt7. These data explain how domain formation and Ypt7 participation can be coordinated. Endosomes are the major protein-sorting hubs of the endocytic pathway. They sort proteins destined for degradation into internal vesicles while in parallel recycling receptors via tubular carriers back to the Golgi. Tubule formation depends on the Rab7/Ypt7-interacting retromer complex, consisting of the sorting nexin dimer (SNX-BAR) and the trimeric cargo selection complex (CSC). Fusion of mature endosomes with the lysosome-like vacuole also requires Rab7/Ypt7. Here we solve a major problem in understanding this dual function of endosomal Rab7/Ypt7, using a fully reconstituted system, including purified, full-length yeast SNX-BAR and CSC, whose overall structure we present. We reveal that the membrane-active SNX-BAR complex displaces Ypt7 from cargo-bound CSC during formation of recycling tubules. This explains how a single Rab can coordinate recycling and fusion on endosomes.
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Affiliation(s)
- Latha Kallur Purushothaman
- Department of Biology/Chemistry, Biochemistry Section, University of Osnabrück, 49076 Osnabrück, Germany
| | - Henning Arlt
- Department of Biology/Chemistry, Biochemistry Section, University of Osnabrück, 49076 Osnabrück, Germany
| | - Anne Kuhlee
- Department of Structural Biochemistry, Max-Planck Institute of Molecular Physiology, 44227 Dortmund, Germany
| | - Stefan Raunser
- Department of Structural Biochemistry, Max-Planck Institute of Molecular Physiology, 44227 Dortmund, Germany
| | - Christian Ungermann
- Department of Biology/Chemistry, Biochemistry Section, University of Osnabrück, 49076 Osnabrück, Germany
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