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Diarra S, Ghosh S, Cissé L, Coulibaly T, Yalcouyé A, Harmison G, Diallo S, Diallo SH, Coulibaly O, Schindler A, Cissé CAK, Maiga AB, Bamba S, Samassekou O, Khokha MK, Mis EK, Lakhani SA, Donovan FX, Jacobson S, Blackstone C, Guinto CO, Landouré G, Bonifacino JS, Fischbeck KH, Grunseich C. AP2A2 mutation and defective endocytosis in a Malian family with hereditary spastic paraplegia. Neurobiol Dis 2024; 198:106537. [PMID: 38772452 PMCID: PMC11209852 DOI: 10.1016/j.nbd.2024.106537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2024] [Revised: 04/17/2024] [Accepted: 05/17/2024] [Indexed: 05/23/2024] Open
Abstract
Hereditary spastic paraplegia (HSP) comprises a large group of neurogenetic disorders characterized by progressive lower extremity spasticity. Neurological evaluation and genetic testing were completed in a Malian family with early-onset HSP. Three children with unaffected consanguineous parents presented with symptoms consistent with childhood-onset complicated HSP. Neurological evaluation found lower limb weakness, spasticity, dysarthria, seizures, and intellectual disability. Brain MRI showed corpus callosum thinning with cortical and spinal cord atrophy, and an EEG detected slow background in the index patient. Whole exome sequencing identified a homozygous missense variant in the adaptor protein (AP) complex 2 alpha-2 subunit (AP2A2) gene. Western blot analysis showed reduced levels of AP2A2 in patient-iPSC derived neuronal cells. Endocytosis of transferrin receptor (TfR) was decreased in patient-derived neurons. In addition, we observed increased axon initial segment length in patient-derived neurons. Xenopus tropicalis tadpoles with ap2a2 knockout showed cerebral edema and progressive seizures. Immunoprecipitation of the mutant human AP-2-appendage alpha-C construct showed defective binding to accessory proteins. We report AP2A2 as a novel genetic entity associated with HSP and provide functional data in patient-derived neuron cells and a frog model. These findings expand our understanding of the mechanism of HSP and improve the genetic diagnosis of this condition.
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Affiliation(s)
- Salimata Diarra
- Université des Sciences, des Techniques, et des Technologies de Bamako (USTTB), Bamako, Mali; Neurogenetics Branch, NINDS, NIH, Bethesda, MD, United States; Yale University, Pediatric Genomics Discovery Program, Department of Pediatrics, New Haven, CT, United States
| | - Saikat Ghosh
- Neurosciences and Cellular and Structural Biology Division, NICHD, NIH, Bethesda, MD, United States
| | - Lassana Cissé
- Service de Neurologie, CHU du Point "G", Bamako, Mali
| | - Thomas Coulibaly
- Université des Sciences, des Techniques, et des Technologies de Bamako (USTTB), Bamako, Mali; Neurosciences and Cellular and Structural Biology Division, NICHD, NIH, Bethesda, MD, United States
| | - Abdoulaye Yalcouyé
- Université des Sciences, des Techniques, et des Technologies de Bamako (USTTB), Bamako, Mali; Division of Human Genetics, Department of Pathology, University of Cape Town, Cape Town, South Africa
| | - George Harmison
- Neurogenetics Branch, NINDS, NIH, Bethesda, MD, United States
| | | | | | - Oumar Coulibaly
- Service de Chirurgie Pédiatrique, CHU du Gabriel Touré, Bamako, Mali
| | - Alice Schindler
- Neurogenetics Branch, NINDS, NIH, Bethesda, MD, United States
| | - Cheick A K Cissé
- Université des Sciences, des Techniques, et des Technologies de Bamako (USTTB), Bamako, Mali
| | - Alassane B Maiga
- Université des Sciences, des Techniques, et des Technologies de Bamako (USTTB), Bamako, Mali; Service de Neurologie, CHU du Point "G", Bamako, Mali
| | - Salia Bamba
- Université des Sciences, des Techniques, et des Technologies de Bamako (USTTB), Bamako, Mali
| | - Oumar Samassekou
- Université des Sciences, des Techniques, et des Technologies de Bamako (USTTB), Bamako, Mali
| | - Mustafa K Khokha
- Yale University, Pediatric Genomics Discovery Program, Department of Pediatrics, New Haven, CT, United States
| | - Emily K Mis
- Yale University, Pediatric Genomics Discovery Program, Department of Pediatrics, New Haven, CT, United States
| | - Saquib A Lakhani
- Yale University, Pediatric Genomics Discovery Program, Department of Pediatrics, New Haven, CT, United States
| | - Frank X Donovan
- Cancer Genetics and Comparative Genomics Branch, NHGRI, NIH, Bethesda, MD, United States
| | - Steve Jacobson
- Neuroimmunology Division, NINDS, NIH, Bethesda, MD, United States
| | - Craig Blackstone
- Movement Disorders Division, Department of Neurology, Harvard Medicine School, Massachusetts General Hospital, Boston, MA, United States
| | - Cheick O Guinto
- Université des Sciences, des Techniques, et des Technologies de Bamako (USTTB), Bamako, Mali; Service de Neurologie, CHU du Point "G", Bamako, Mali
| | - Guida Landouré
- Université des Sciences, des Techniques, et des Technologies de Bamako (USTTB), Bamako, Mali; Neurogenetics Branch, NINDS, NIH, Bethesda, MD, United States; Service de Neurologie, CHU du Point "G", Bamako, Mali
| | - Juan S Bonifacino
- Neurosciences and Cellular and Structural Biology Division, NICHD, NIH, Bethesda, MD, United States
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Kraus M, Pleskot R, Van Damme D. Structural and Evolutionary Aspects of Plant Endocytosis. ANNUAL REVIEW OF PLANT BIOLOGY 2024; 75:521-550. [PMID: 38237062 DOI: 10.1146/annurev-arplant-070122-023455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/24/2024]
Abstract
Endocytosis is an essential eukaryotic process that maintains the homeostasis of the plasma membrane proteome by vesicle-mediated internalization. Its predominant mode of operation utilizes the polymerization of the scaffold protein clathrin forming a coat around the vesicle; therefore, it is termed clathrin-mediated endocytosis (CME). Throughout evolution, the machinery that mediates CME is marked by losses, multiplications, and innovations. CME employs a limited number of conserved structural domains and folds, whose assembly and connections are species dependent. In plants, many of the domains are grouped into an ancient multimeric complex, the TPLATE complex, which occupies a central position as an interaction hub for the endocytic machinery. In this review, we provide an overview of the current knowledge regarding the structural aspects of plant CME, and we draw comparisons to other model systems. To do so, we have taken advantage of recent developments with respect to artificial intelligence-based protein structure prediction.
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Affiliation(s)
- Michael Kraus
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium; ,
- VIB Center for Plant Systems Biology, Ghent, Belgium
| | - Roman Pleskot
- Institute of Experimental Botany, Czech Academy of Sciences, Prague, Czech Republic;
| | - Daniël Van Damme
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium; ,
- VIB Center for Plant Systems Biology, Ghent, Belgium
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3
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Griffiths G, Brügger B, Freund C. Lipid switches in the immunological synapse. J Biol Chem 2024; 300:107428. [PMID: 38823638 PMCID: PMC11259711 DOI: 10.1016/j.jbc.2024.107428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 05/07/2024] [Accepted: 05/26/2024] [Indexed: 06/03/2024] Open
Abstract
Adaptive immune responses comprise the activation of T cells by peptide antigens that are presented by proteins of the Major Histocompatibility Complex (MHC) on the surface of an antigen-presenting cell. As a consequence of the T cell receptor interacting productively with a certain peptide-MHC complex, a specialized cell-cell junction known as the immunological synapse forms and is accompanied by changes in the spatiotemporal patterning and function of intracellular signaling molecules. Key modifications occurring at the cytoplasmic leaflet of the plasma and internal membranes in activated T cells comprise lipid switches that affect the binding and distribution of proteins within or near the lipid bilayer. Here, we describe two major classes of lipid switches that act at this critical water/membrane interface. Phosphoinositides are derived from phosphatidylinositol, an amphiphilic molecule that contains two fatty acid chains and a phosphate group that bridges the glycerol backbone to the carbohydrate inositol. The inositol ring can be variably (de-)phosphorylated by dedicated kinases and phosphatases, thereby creating phosphoinositide signatures that define the composition and properties of signaling molecules, molecular complexes, or whole organelles. Palmitoylation refers to the reversible attachment of the fatty acid palmitate to a substrate protein's cysteine residue. DHHC enzymes, named after the four conserved amino acids in their active site, catalyze this post-translational modification and thereby change the distribution of proteins at, between, and within membranes. T cells utilize these two types of molecular switches to adjust their properties to an activation process that requires changes in motility, transport, secretion, and gene expression.
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Affiliation(s)
| | - Britta Brügger
- Heidelberg University Biochemistry Center (BZH), Heidelberg, Germany
| | - Christian Freund
- Laboratory of Protein Biochemistry, Institute of Chemistry & Biochemistry, Freie Universität Berlin, Berlin, Germany.
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4
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Begley M, Aragon M, Baker RW. A structure-based mechanism for initiation of AP-3 coated vesicle formation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.05.597630. [PMID: 38895279 PMCID: PMC11185636 DOI: 10.1101/2024.06.05.597630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
Adaptor protein complex 3 (AP-3) mediates cargo sorting from endosomes to lysosomes and lysosome-related organelles. Recently, it was shown that AP-3 is in a constitutively open, active conformation compared to the related AP-1 and AP-2 coat complexes, which are inactive until undergoing large conformational changes upon membrane recruitment. How AP-3 is regulated is therefore an open question. To understand the mechanism of AP-3 membrane recruitment and activation, we reconstituted the core of human AP-3 and determined multiple structures in the soluble and membrane-bound states using electron cryo-microscopy (cryo-EM). Similar to yeast AP-3, human AP-3 is in a constitutively open conformation, with the cargo-binding domain of the μ3 subunit conformationally free. To reconstitute AP-3 activation by the small GTPase Arf1, we used lipid nanodiscs to build Arf1-AP-3 complexes on membranes and determined three structures that show the stepwise conformational changes required for formation of AP-3 coated vesicles. First, membrane-recruitment is driven by one of two predicted Arf1 binding sites on AP-3. In this conformation, AP-3 is flexibly tethered to the membrane and its cargo binding domain remains conformationally dynamic. Second, cargo binding causes AP-3 to adopt a fixed position and rigidifies the complex, which stabilizes binding for a second Arf1 molecule. Finally, binding of the second Arf1 molecule provides the template for AP-3 dimerization, providing a glimpse into the first step of coat polymerization. We propose coat polymerization only occurs after cargo engagement, thereby linking cargo sorting with assembly of higher order coat structures. Additionally, we provide evidence for two amphipathic helices in AP-3, suggesting that AP-3 contributes to membrane deformation during coat assembly. In total, these data provide evidence for the first stages of AP-3 mediated vesicle coat assembly.
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Affiliation(s)
- Matthew Begley
- Department of Biochemistry and Biophysics, UNC Chapel Hill School of Medicine; Chapel Hill, NC 27516, USA
| | - Mahira Aragon
- New York Structural Biology Center; New York, NY 10027, USA
| | - Richard W. Baker
- Department of Biochemistry and Biophysics, UNC Chapel Hill School of Medicine; Chapel Hill, NC 27516, USA
- UNC Lineberger Comprehensive Cancer Center. UNC Chapel Hill School of Medicine; Chapel Hill, NC 27516, USA
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5
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Rademacher K, Doric Z, Haddad D, Mamaligas A, Liao SC, Creed RB, Kano K, Chatterton Z, Fu Y, Garcia JH, Vance V, Sei Y, Kreitzer A, Halliday GM, Nelson AB, Margolis EB, Nakamura K. Chronic hyperactivation of midbrain dopamine neurons causes preferential dopamine neuron degeneration. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.05.588321. [PMID: 38645054 PMCID: PMC11030348 DOI: 10.1101/2024.04.05.588321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
Parkinson's disease (PD) is characterized by the death of substantia nigra (SNc) dopamine (DA) neurons, but the pathophysiological mechanisms that precede and drive their death remain unknown. The activity of DA neurons is likely altered in PD, but we understand little about if or how chronic changes in activity may contribute to degeneration. To address this question, we developed a chemogenetic (DREADD) mouse model to chronically increase DA neuron activity, and confirmed this increase using ex vivo electrophysiology. Chronic hyperactivation of DA neurons resulted in prolonged increases in locomotor activity during the light cycle and decreases during the dark cycle, consistent with chronic changes in DA release and circadian disturbances. We also observed early, preferential degeneration of SNc projections, recapitulating the PD hallmarks of selective vulnerability of SNc axons and the comparative resilience of ventral tegmental area axons. This was followed by eventual loss of midbrain DA neurons. Continuous DREADD activation resulted in a sustained increase in baseline calcium levels, supporting an important role for increased calcium in the neurodegeneration process. Finally, spatial transcriptomics from DREADD mice examining midbrain DA neurons and striatal targets, and cross-validation with human patient samples, provided insights into potential mechanisms of hyperactivity-induced toxicity and PD. Our results thus reveal the preferential vulnerability of SNc DA neurons to increased neural activity, and support a potential role for increased neural activity in driving degeneration in PD.
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6
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Zhang C, Chen L, Hou S. The emerging roles of clathrin-mediated endocytosis in plant development and stress responses. JOURNAL OF PLANT PHYSIOLOGY 2024; 295:154189. [PMID: 38432037 DOI: 10.1016/j.jplph.2024.154189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 01/22/2024] [Accepted: 02/01/2024] [Indexed: 03/05/2024]
Abstract
Clathrin-mediated endocytosis (CME) is a highly conserved pathway that plays a crucial role in the endocytosis of plasma membrane proteins in eukaryotic cells. The pathway is initiated when the adaptor protein complex 2 (AP2) and TPLATE complex (TPC) work together to recognize cargo proteins and recruit clathrin. This review provides a concise overview of the functions of each subunit of AP2 and TPC, and highlights the involvement of CME in various biological processes, such as pollen development, root development, nutrient transport, extracellular signal transduction, auxin polar transport, hyperosmotic stress, salinity stress, high ammonium stress, and disease resistance. Additionally, the review explores the regulation of CME by phytohormones, clathrin-mediated exocytosis (CMX), and AP2M phosphorylation. It also suggests potential future research directions for CME.
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Affiliation(s)
- Chi Zhang
- Key Laboratory of Gene Editing for Breeding, Gansu Province, Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Liang Chen
- Key Laboratory of Gene Editing for Breeding, Gansu Province, Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China
| | - Suiwen Hou
- Key Laboratory of Gene Editing for Breeding, Gansu Province, Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou, 730000, China.
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7
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Matsubayashi HT, Mountain J, Takahashi N, Deb Roy A, Yao T, Peterson AF, Saez Gonzalez C, Kawamata I, Inoue T. Non-catalytic role of phosphoinositide 3-kinase in mesenchymal cell migration through non-canonical induction of p85β/AP2-mediated endocytosis. Nat Commun 2024; 15:2612. [PMID: 38521786 PMCID: PMC10960865 DOI: 10.1038/s41467-024-46855-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 03/13/2024] [Indexed: 03/25/2024] Open
Abstract
Class IA phosphoinositide 3-kinase (PI3K) galvanizes fundamental cellular processes such as migration, proliferation, and differentiation. To enable these multifaceted roles, the catalytic subunit p110 utilizes the multi-domain, regulatory subunit p85 through its inter SH2 domain (iSH2). In cell migration, its product PI(3,4,5)P3 generates locomotive activity. While non-catalytic roles are also implicated, underlying mechanisms and their relationship to PI(3,4,5)P3 signaling remain elusive. Here, we report that a disordered region of iSH2 contains AP2 binding motifs which can trigger clathrin and dynamin-mediated endocytosis independent of PI3K catalytic activity. The AP2 binding motif mutants of p85 aberrantly accumulate at focal adhesions and increase both velocity and persistency in fibroblast migration. We thus propose the dual functionality of PI3K in the control of cell motility, catalytic and non-catalytic, arising distinctly from juxtaposed regions within iSH2.
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Affiliation(s)
- Hideaki T Matsubayashi
- Department of Cell Biology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA.
- Center for Cell Dynamics, Institute of Basic Biomedical Sciences, Johns Hopkins University, Baltimore, MD, USA.
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Tohoku, Japan.
| | - Jack Mountain
- Department of Cell Biology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
- Center for Cell Dynamics, Institute of Basic Biomedical Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Nozomi Takahashi
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Tohoku, Japan
| | - Abhijit Deb Roy
- Department of Cell Biology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
- Center for Cell Dynamics, Institute of Basic Biomedical Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Tony Yao
- Department of Cell Biology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
- Center for Cell Dynamics, Institute of Basic Biomedical Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Amy F Peterson
- Department of Cell Biology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
- Center for Cell Dynamics, Institute of Basic Biomedical Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Cristian Saez Gonzalez
- Department of Cell Biology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA
- Center for Cell Dynamics, Institute of Basic Biomedical Sciences, Johns Hopkins University, Baltimore, MD, USA
| | - Ibuki Kawamata
- Department of Robotics, Tohoku University, Tohoku, Japan
- Natural Science Division, Ochanomizu University, Kyoto, Japan
- Graduate School of Science, Kyoto University, Kyoto, Japan
| | - Takanari Inoue
- Department of Cell Biology, School of Medicine, Johns Hopkins University, Baltimore, MD, USA.
- Center for Cell Dynamics, Institute of Basic Biomedical Sciences, Johns Hopkins University, Baltimore, MD, USA.
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8
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Carter T, Iqbal M. The Influenza A Virus Replication Cycle: A Comprehensive Review. Viruses 2024; 16:316. [PMID: 38400091 PMCID: PMC10892522 DOI: 10.3390/v16020316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 02/15/2024] [Accepted: 02/17/2024] [Indexed: 02/25/2024] Open
Abstract
Influenza A virus (IAV) is the primary causative agent of influenza, colloquially called the flu. Each year, it infects up to a billion people, resulting in hundreds of thousands of human deaths, and causes devastating avian outbreaks with worldwide losses worth billions of dollars. Always present is the possibility that a highly pathogenic novel subtype capable of direct human-to-human transmission will spill over into humans, causing a pandemic as devastating if not more so than the 1918 influenza pandemic. While antiviral drugs for influenza do exist, they target very few aspects of IAV replication and risk becoming obsolete due to antiviral resistance. Antivirals targeting other areas of IAV replication are needed to overcome this resistance and combat the yearly epidemics, which exact a serious toll worldwide. This review aims to summarise the key steps in the IAV replication cycle, along with highlighting areas of research that need more focus.
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Affiliation(s)
- Toby Carter
- The Pirbright Institute, Ash Road, Pirbright, Woking GU24 0NF, UK;
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9
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Black JA, Klinger CM, Lemgruber L, Dacks JB, Mottram JC, McCulloch R. AAK1-like: A putative pseudokinase with potential roles in cargo uptake in bloodstream form Trypanosoma brucei parasites. J Eukaryot Microbiol 2023; 70:e12994. [PMID: 37548427 PMCID: PMC10952953 DOI: 10.1111/jeu.12994] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 07/21/2023] [Accepted: 07/21/2023] [Indexed: 08/08/2023]
Abstract
Selection and internalization of cargo via clathrin-mediated endocytosis requires adaptor protein complexes. One complex, AP-2, acts during cargo selection at the plasma membrane. African trypanosomes lack all components of the AP-2 complex, except for a recently identified orthologue of the AP-2-associated protein kinase 1, AAK1. In characterized eukaryotes, AAK1 phosphorylates the μ2 subunit of the AP-2 complex to enhance cargo recognition and uptake into clathrin-coated vesicles. Here, we show that kinetoplastids encode not one, but two AAK1 orthologues: one (AAK1L2) is absent from salivarian trypanosomes, while the other (AAK1L1) lacks important kinase-specific residues in a range of trypanosomes. These AAK1L1 and AAK1L2 novelties reinforce suggestions of functional divergence in endocytic uptake within salivarian trypanosomes. Despite this, we show that AAK1L1 null mutant Trypanosoma brucei, while viable, display slowed proliferation, morphological abnormalities including swelling of the flagellar pocket, and altered cargo uptake. In summary, our data suggest an unconventional role for a putative pseudokinase during endocytosis and/or vesicular trafficking in T. brucei, independent of AP-2.
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Affiliation(s)
- Jennifer A. Black
- The Wellcome Centre for Integrative Parasitology, School of Infection & ImmunityUniversity of GlasgowGlasgowUK
- Department of Cell and Molecular Biology, Ribeirão Preto Medical SchoolUniversity of São PauloSão PauloBrazil
| | - Christen M. Klinger
- The Wellcome Centre for Integrative Parasitology, School of Infection & ImmunityUniversity of GlasgowGlasgowUK
- Division of Infectious Diseases, Department of Medicine, Li Ka Shing Centre for Health, Research InnovationUniversity of AlbertaEdmontonAlbertaCanada
| | - Leandro Lemgruber
- The Wellcome Centre for Integrative Parasitology, School of Infection & ImmunityUniversity of GlasgowGlasgowUK
- Glasgow Imaging Facility, School of Infection & ImmunityUniversity of GlasgowGlasgowUK
| | - Joel B. Dacks
- Department of Cell and Molecular Biology, Ribeirão Preto Medical SchoolUniversity of São PauloSão PauloBrazil
- Institute of Parasitology, Biology CentreCzech Academy of SciencesCeske Budejovice (Budweis)Czech Republic
| | - Jeremy C. Mottram
- York Biomedical Research Institute and Department of BiologyUniversity of YorkYorkUK
| | - Richard McCulloch
- The Wellcome Centre for Integrative Parasitology, School of Infection & ImmunityUniversity of GlasgowGlasgowUK
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10
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S Cannon K, Sarsam RD, Tedamrongwanish T, Zhang K, Baker RW. Lipid nanodiscs as a template for high-resolution cryo-EM structures of peripheral membrane proteins. J Struct Biol 2023; 215:107989. [PMID: 37364761 DOI: 10.1016/j.jsb.2023.107989] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 06/05/2023] [Accepted: 06/23/2023] [Indexed: 06/28/2023]
Abstract
Peripheral membrane proteins are ubiquitous throughout cell biology and are required for a variety of cellular processes such as signal transduction, membrane trafficking, and autophagy. Transient binding to the membrane has a profound impact on protein function, serving to induce conformational changes and alter biochemical and biophysical parameters by increasing the local concentration of factors and restricting diffusion to two dimensions. Despite the centrality of the membrane in serving as a template for cell biology, there are few reported high-resolution structures of peripheral membrane proteins bound to the membrane. We analyzed the utility of lipid nanodiscs to serve as a template for cryo-EM analysis of peripheral membrane proteins. We tested a variety of nanodiscs and we report a 3.3 Å structure of the AP2 clathrin adaptor complex bound to a 17-nm nanodisc, with sufficient resolution to visualize a bound lipid head group. Our data demonstrate that lipid nanodiscs are amenable to high-resolution structure determination of peripheral membrane proteins and provide a framework for extending this analysis to other systems.
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Affiliation(s)
- Kevin S Cannon
- Department of Biochemistry and Biophysics, UNC Chapel Hill School of Medicine, Chapel Hill, NC 27516, USA
| | - Reta D Sarsam
- Department of Biochemistry and Biophysics, UNC Chapel Hill School of Medicine, Chapel Hill, NC 27516, USA
| | - Tanita Tedamrongwanish
- Department of Biochemistry and Biophysics, UNC Chapel Hill School of Medicine, Chapel Hill, NC 27516, USA
| | - Kevin Zhang
- Department of Biochemistry and Biophysics, UNC Chapel Hill School of Medicine, Chapel Hill, NC 27516, USA
| | - Richard W Baker
- Department of Biochemistry and Biophysics, UNC Chapel Hill School of Medicine, Chapel Hill, NC 27516, USA; UNC Lineberger Comprehensive Cancer Center, UNC Chapel Hill School of Medicine, Chapel Hill, NC 27516, USA.
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11
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Siao W, Wang P, Zhao X, Vu LD, De Smet I, Russinova E. Phosphorylation of ADAPTOR PROTEIN-2 μ-adaptin by ADAPTOR-ASSOCIATED KINASE1 regulates the tropic growth of Arabidopsis roots. THE PLANT CELL 2023; 35:3504-3521. [PMID: 37440281 PMCID: PMC10473204 DOI: 10.1093/plcell/koad141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 04/21/2023] [Indexed: 07/14/2023]
Abstract
ADAPTOR-ASSOCIATED PROTEIN KINASE1 (AAK1) is a known regulator of clathrin-mediated endocytosis in mammals. Human AAK1 phosphorylates the μ2 subunit of the ADAPTOR PROTEIN-2 (AP-2) complex (AP2M) and plays important roles in cell differentiation and development. Previous interactome studies discovered the association of AAK1 with AP-2 in Arabidopsis (Arabidopsis thaliana), but its function was unclear. Here, genetic analysis revealed that the Arabidopsis aak1 and ap2m mutants both displayed altered root tropic growth, including impaired touch- and gravity-sensing responses. In Arabidopsis, AAK1-phosphorylated AP2M on Thr-163, and expression of the phospho-null version of AP2M in the ap2m mutant led to an aak1-like phenotype, whereas the phospho-mimic forms of AP2M rescued the aak1 mutant. In addition, we found that the AAK1-dependent phosphorylation state of AP2M modulates the frequency distribution of endocytosis. Our data indicate that the phosphorylation of AP2M on Thr-163 by AAK1 fine-tunes endocytosis in the Arabidopsis root to control its tropic growth.
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Affiliation(s)
- Wei Siao
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
- Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium
| | - Peng Wang
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
- Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium
| | - Xiuyang Zhao
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
- Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium
| | - Lam Dai Vu
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
- Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium
| | - Ive De Smet
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
- Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium
| | - Eugenia Russinova
- Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium
- Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium
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Cheng Y, Kang XZ, Chan P, Cheung PHH, Cheng T, Ye ZW, Chan CP, Yu CH, Jin DY. FACI is a novel clathrin adaptor protein 2-binding protein that facilitates low-density lipoprotein endocytosis. Cell Biosci 2023; 13:74. [PMID: 37072871 PMCID: PMC10114425 DOI: 10.1186/s13578-023-01023-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 03/27/2023] [Indexed: 04/20/2023] Open
Abstract
BACKGROUND Cholesterol plays a vital role in multiple physiological processes. Cellular uptake of cholesterol is mediated primarily through endocytosis of low-density lipoprotein (LDL) receptor. New modifiers of this process remain to be characterized. Particularly, the role of fasting- and CREB-H-induced (FACI) protein in cholesterol homeostasis merits further investigation. METHODS Interactome profiling by proximity labeling and affinity purification - mass spectrometry was performed. Total internal reflection fluorescence microscopy and confocal immunofluorescence microscopy were used to analyze protein co-localization and interaction. Mutational analysis was carried out to define the domain and residues required for FACI localization and function. Endocytosis was traced by fluorescent cargos. LDL uptake in cultured cells and diet-induced hypercholesterolemia in mice were assessed. RESULTS FACI interacted with proteins critically involved in clathrin-mediated endocytosis, vesicle trafficking, and membrane cytoskeleton. FACI localized to clathrin-coated pits (CCP) on plasma membranes. FACI contains a conserved DxxxLI motif, which mediates its binding with the adaptor protein 2 (AP2) complex. Disruption of this motif of FACI abolished its CCP localization but didn't affect its association with plasma membrane. Cholesterol was found to facilitate FACI transport from plasma membrane to endocytic recycling compartment in a clathrin- and cytoskeleton-dependent manner. LDL endocytosis was enhanced in FACI-overexpressed AML12 cells but impaired in FACI-depleted HeLa cells. In vivo study indicated that hepatic FACI overexpression alleviated diet-induced hypercholesterolemia in mice. CONCLUSIONS FACI facilitates LDL endocytosis through its interaction with the AP2 complex.
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Affiliation(s)
- Yun Cheng
- School of Biomedical Sciences, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong.
- State Key Laboratory of Liver Research, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong.
| | - Xiao-Zhuo Kang
- School of Biomedical Sciences, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong
- State Key Laboratory of Liver Research, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong
| | - Pearl Chan
- School of Biomedical Sciences, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong
- State Key Laboratory of Liver Research, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong
| | - Pak-Hin Hinson Cheung
- School of Biomedical Sciences, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong
- State Key Laboratory of Liver Research, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong
| | - Tao Cheng
- School of Biomedical Sciences, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong
- State Key Laboratory of Liver Research, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong
| | - Zi-Wei Ye
- School of Biomedical Sciences, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong
| | - Chi-Ping Chan
- School of Biomedical Sciences, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong
- State Key Laboratory of Liver Research, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong
| | - Cheng-Han Yu
- School of Biomedical Sciences, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong
| | - Dong-Yan Jin
- School of Biomedical Sciences, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong.
- State Key Laboratory of Liver Research, The University of Hong Kong, 21 Sassoon Road, Pokfulam, Hong Kong.
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13
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Xie B, Guillem C, Date SS, Cohen CI, Jung C, Kendall AK, Best JT, Graham TR, Jackson LP. An interaction between β'-COP and the ArfGAP, Glo3, maintains post-Golgi cargo recycling. J Cell Biol 2023; 222:e202008061. [PMID: 36811888 PMCID: PMC9960064 DOI: 10.1083/jcb.202008061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 07/14/2022] [Accepted: 01/24/2023] [Indexed: 02/24/2023] Open
Abstract
The essential COPI coat mediates retrieval of transmembrane proteins at the Golgi and endosomes following recruitment by the small GTPase, Arf1. ArfGAP proteins regulate COPI coats, but molecular details for COPI recognition by ArfGAPs remain elusive. Biochemical and biophysical data reveal how β'-COP propeller domains directly engage the yeast ArfGAP, Glo3, with a low micromolar binding affinity. Calorimetry data demonstrate that both β'-COP propeller domains are required to bind Glo3. An acidic patch on β'-COP (D437/D450) interacts with Glo3 lysine residues located within the BoCCS (binding of coatomer, cargo, and SNAREs) region. Targeted point mutations in either Glo3 BoCCS or β'-COP abrogate the interaction in vitro, and loss of the β'-COP/Glo3 interaction drives Ste2 missorting to the vacuole and aberrant Golgi morphology in budding yeast. These data suggest that cells require the β'-COP/Glo3 interaction for cargo recycling via endosomes and the TGN, where β'-COP serves as a molecular platform to coordinate binding to multiple proteins, including Glo3, Arf1, and the COPI F-subcomplex.
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Affiliation(s)
- Boyang Xie
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, USA
- Center for Structural Biology, Vanderbilt University, Nashville, TN, USA
| | - Clara Guillem
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, USA
| | - Swapneeta S. Date
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, USA
| | - Cameron I. Cohen
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, USA
| | - Christian Jung
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, USA
| | - Amy K. Kendall
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, USA
- Center for Structural Biology, Vanderbilt University, Nashville, TN, USA
| | - Jordan T. Best
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, USA
| | - Todd R. Graham
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, USA
| | - Lauren P. Jackson
- Department of Biological Sciences, Vanderbilt University, Nashville, TN, USA
- Center for Structural Biology, Vanderbilt University, Nashville, TN, USA
- Department of Biochemistry, Vanderbilt University, Nashville, TN, USA
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14
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Taylor RJ, Tagiltsev G, Briggs JAG. The structure of COPI vesicles and regulation of vesicle turnover. FEBS Lett 2023; 597:819-835. [PMID: 36513395 DOI: 10.1002/1873-3468.14560] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 11/30/2022] [Accepted: 12/02/2022] [Indexed: 12/15/2022]
Abstract
COPI-coated vesicles mediate transport between Golgi stacks and retrograde transport from the Golgi to the endoplasmic reticulum. The COPI coat exists as a stable heptameric complex in the cytosol termed coatomer and is recruited en bloc to the membrane for vesicle formation. Recruitment of COPI onto membranes is mediated by the Arf family of small GTPases, which, in their GTP-bound state, bind both membrane and coatomer. Arf GTPases also influence cargo selection, vesicle scission and vesicle uncoating. Guanine nucleotide exchange factors (GEFs) and GTPase-activating proteins (GAPs) regulate nucleotide binding by Arf GTPases. To understand the mechanism of COPI-coated vesicle trafficking, it is necessary to characterize the interplay between coatomer and Arf GTPases and their effectors. It is also necessary to understand interactions between coatomer and cargo, cargo adaptors/receptors and tethers facilitating binding to the target membrane. Here, we summarize current knowledge of COPI coat protein structure; we describe how structural and biochemical studies contributed to this knowledge; we review mechanistic insights into COPI vesicle biogenesis and disassembly; and we discuss the potential to answer open questions in the field.
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Affiliation(s)
- Rebecca J Taylor
- Department of Cell and Virus Structure, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Grigory Tagiltsev
- Department of Cell and Virus Structure, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - John A G Briggs
- Department of Cell and Virus Structure, Max Planck Institute of Biochemistry, Martinsried, Germany
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15
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Wang Y, Zhu CL, Li P, Liu Q, Li HR, Yu CM, Deng XM, Wang JF. The role of G protein-coupled receptor in neutrophil dysfunction during sepsis-induced acute respiratory distress syndrome. Front Immunol 2023; 14:1112196. [PMID: 36891309 PMCID: PMC9986442 DOI: 10.3389/fimmu.2023.1112196] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Accepted: 02/07/2023] [Indexed: 02/22/2023] Open
Abstract
Sepsis is defined as a life-threatening dysfunction due to a dysregulated host response to infection. It is a common and complex syndrome and is the leading cause of death in intensive care units. The lungs are most vulnerable to the challenge of sepsis, and the incidence of respiratory dysfunction has been reported to be up to 70%, in which neutrophils play a major role. Neutrophils are the first line of defense against infection, and they are regarded as the most responsive cells in sepsis. Normally, neutrophils recognize chemokines including the bacterial product N-formyl-methionyl-leucyl-phenylalanine (fMLP), complement 5a (C5a), and lipid molecules Leukotriene B4 (LTB4) and C-X-C motif chemokine ligand 8 (CXCL8), and enter the site of infection through mobilization, rolling, adhesion, migration, and chemotaxis. However, numerous studies have confirmed that despite the high levels of chemokines in septic patients and mice at the site of infection, the neutrophils cannot migrate to the proper target location, but instead they accumulate in the lungs, releasing histones, DNA, and proteases that mediate tissue damage and induce acute respiratory distress syndrome (ARDS). This is closely related to impaired neutrophil migration in sepsis, but the mechanism involved is still unclear. Many studies have shown that chemokine receptor dysregulation is an important cause of impaired neutrophil migration, and the vast majority of these chemokine receptors belong to the G protein-coupled receptors (GPCRs). In this review, we summarize the signaling pathways by which neutrophil GPCR regulates chemotaxis and the mechanisms by which abnormal GPCR function in sepsis leads to impaired neutrophil chemotaxis, which can further cause ARDS. Several potential targets for intervention are proposed to improve neutrophil chemotaxis, and we hope that this review may provide insights for clinical practitioners.
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Affiliation(s)
- Yi Wang
- Faculty of Anesthesiology, Changhai Hospital, Naval Medical University, Shanghai, China
| | - Cheng-Long Zhu
- Faculty of Anesthesiology, Changhai Hospital, Naval Medical University, Shanghai, China
| | - Peng Li
- Faculty of Anesthesiology, Changhai Hospital, Naval Medical University, Shanghai, China
| | - Qiang Liu
- Faculty of Anesthesiology, Changhai Hospital, Naval Medical University, Shanghai, China.,Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Hui-Ru Li
- Faculty of Anesthesiology, Changhai Hospital, Naval Medical University, Shanghai, China.,Faculty of Anesthesiology, Weifang Medical University, Weifang, Shandong, China
| | - Chang-Meng Yu
- Faculty of Anesthesiology, Changhai Hospital, Naval Medical University, Shanghai, China.,Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, Jiangsu, China
| | - Xiao-Ming Deng
- Faculty of Anesthesiology, Changhai Hospital, Naval Medical University, Shanghai, China.,Jiangsu Province Key Laboratory of Anesthesiology, Xuzhou Medical University, Xuzhou, Jiangsu, China.,Faculty of Anesthesiology, Weifang Medical University, Weifang, Shandong, China
| | - Jia-Feng Wang
- Faculty of Anesthesiology, Changhai Hospital, Naval Medical University, Shanghai, China
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16
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Hooy RM, Iwamoto Y, Tudorica DA, Ren X, Hurley JH. Self-assembly and structure of a clathrin-independent AP-1:Arf1 tubular membrane coat. SCIENCE ADVANCES 2022; 8:eadd3914. [PMID: 36269825 PMCID: PMC9586487 DOI: 10.1126/sciadv.add3914] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 09/01/2022] [Indexed: 05/28/2023]
Abstract
The adaptor protein (AP) complexes not only form the inner layer of clathrin coats but also have clathrin-independent roles in membrane traffic whose mechanisms are unknown. HIV-1 Nef hijacks AP-1 to sequester major histocompatibility complex class I (MHC-I), evading immune detection. We found that AP-1:Arf1:Nef:MHC-I forms a coat on tubulated membranes without clathrin and determined its structure. The coat assembles via Arf1 dimer interfaces. AP-1-positive tubules are enriched in cells upon clathrin knockdown. Nef localizes preferentially to AP-1 tubules in cells, explaining how Nef sequesters MHC-I. Coat contact residues are conserved across Arf isoforms and the Arf-dependent AP complexes AP-1, AP-3, and AP-4. Thus, AP complexes can self-assemble with Arf1 into tubular coats without clathrin or other scaffolding factors. The AP-1:Arf1 coat defines the structural basis of a broader class of tubulovesicular membrane coats as an intermediate in clathrin vesicle formation from internal membranes and as an MHC-I sequestration mechanism in HIV-1 infection.
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Affiliation(s)
- Richard M. Hooy
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
- California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Yuichiro Iwamoto
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
- California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Dan A. Tudorica
- California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, CA 94720, USA
- Graduate Group in Biophysics, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Xuefeng Ren
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
- California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, CA 94720, USA
| | - James H. Hurley
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
- California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, CA 94720, USA
- Graduate Group in Biophysics, University of California, Berkeley, Berkeley, CA 94720, USA
- Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, CA 94720, USA
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17
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Date SS, Xu P, Hepowit NL, Diab NS, Best J, Xie B, Du J, Strieter ER, Jackson LP, MacGurn JA, Graham TR. Ubiquitination drives COPI priming and Golgi SNARE localization. eLife 2022; 11:e80911. [PMID: 35904239 PMCID: PMC9374436 DOI: 10.7554/elife.80911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 07/01/2022] [Indexed: 11/15/2022] Open
Abstract
Deciphering mechanisms controlling SNARE localization within the Golgi complex is crucial to understanding protein trafficking patterns within the secretory pathway. SNAREs are also thought to prime coatomer protein I (COPI) assembly to ensure incorporation of these essential cargoes into vesicles, but the regulation of these events is poorly understood. Here, we report roles for ubiquitin recognition by COPI in SNARE trafficking and in stabilizing interactions between Arf, COPI, and Golgi SNAREs in Saccharomyces cerevisiae. The ability of COPI to bind ubiquitin, but not the dilysine motif, through its N-terminal WD repeat domain of β'-COP or through an unrelated ubiquitin-binding domain is essential for the proper localization of Golgi SNAREs Bet1 and Gos1. We find that COPI, the ArfGAP Glo3, and multiple Golgi SNAREs are ubiquitinated. Notably, the binding of Arf and COPI to Gos1 is markedly enhanced by ubiquitination of these components. Glo3 is proposed to prime COPI-SNARE interactions; however, Glo3 is not enriched in the ubiquitin-stabilized SNARE-Arf-COPI complex but is instead enriched with COPI complexes that lack SNAREs. These results support a new model for how posttranslational modifications drive COPI priming events crucial for Golgi SNARE localization.
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Affiliation(s)
- Swapneeta S Date
- Department of Biological Sciences, Vanderbilt UniversityNashvilleUnited States
| | - Peng Xu
- Department of Biological Sciences, Vanderbilt UniversityNashvilleUnited States
| | - Nathaniel L Hepowit
- Department of Cell and Developmental Biology, Vanderbilt UniversityNashvilleUnited States
| | - Nicholas S Diab
- Department of Biological Sciences, Vanderbilt UniversityNashvilleUnited States
| | - Jordan Best
- Department of Biological Sciences, Vanderbilt UniversityNashvilleUnited States
| | - Boyang Xie
- Department of Biological Sciences, Vanderbilt UniversityNashvilleUnited States
| | - Jiale Du
- Department of Chemistry, University of Massachusetts AmherstAmherstUnited States
| | - Eric R Strieter
- Department of Chemistry, University of Massachusetts AmherstAmherstUnited States
| | - Lauren P Jackson
- Department of Biological Sciences, Vanderbilt UniversityNashvilleUnited States
| | - Jason A MacGurn
- Department of Cell and Developmental Biology, Vanderbilt UniversityNashvilleUnited States
| | - Todd R Graham
- Department of Biological Sciences, Vanderbilt UniversityNashvilleUnited States
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18
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Smith SM, Smith CJ. Capturing the mechanics of clathrin-mediated endocytosis. Curr Opin Struct Biol 2022; 75:102427. [PMID: 35872561 DOI: 10.1016/j.sbi.2022.102427] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 06/13/2022] [Accepted: 06/16/2022] [Indexed: 02/01/2023]
Abstract
Clathrin-mediated endocytosis enables selective uptake of molecules into cells in response to changing cellular needs. It occurs through assembly of coat components around the plasma membrane that determine vesicle contents and facilitate membrane bending to form a clathrin-coated transport vesicle. In this review we discuss recent cryo-electron microscopy structures that have captured a series of events in the life cycle of a clathrin-coated vesicle. Both single particle analysis and tomography approaches have revealed details of the clathrin lattice structure itself, how AP2 may interface with clathrin within a coated vesicle and the importance of PIP2 binding for assembly of the yeast adaptors Sla2 and Ent1 on the membrane. Within cells, cryo-electron tomography of clathrin in flat lattices and high-speed AFM studies provided new insights into how clathrin morphology can adapt during CCV formation. Thus, key mechanical processes driving clathrin-mediated endocytosis have been captured through multiple techniques working in partnership.
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Affiliation(s)
- Sarah M Smith
- School of Life Sciences, University of Warwick, Coventry, UK
| | - Corinne J Smith
- School of Life Sciences, University of Warwick, Coventry, UK.
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19
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Cail RC, Shirazinejad CR, Drubin DG. Induced nanoscale membrane curvature bypasses the essential endocytic function of clathrin. J Cell Biol 2022; 221:e202109013. [PMID: 35532382 PMCID: PMC9093045 DOI: 10.1083/jcb.202109013] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Revised: 12/09/2021] [Accepted: 04/21/2022] [Indexed: 01/07/2023] Open
Abstract
During clathrin-mediated endocytosis (CME), flat plasma membrane is remodeled to produce nanometer-scale vesicles. The mechanisms underlying this remodeling are not completely understood. The ability of clathrin to bind membranes of distinct geometries casts uncertainty on its specific role in curvature generation/stabilization. Here, we used nanopatterning to produce substrates for live-cell imaging, with U-shaped features that bend the ventral plasma membrane of a cell into shapes resembling energetically unfavorable CME intermediates. This induced membrane curvature recruits CME proteins, promoting endocytosis. Upon AP2, FCHo1/2, or clathrin knockdown, CME on flat substrates is severely diminished. However, induced membrane curvature recruits CME proteins in the absence of FCHo1/2 or clathrin and rescues CME dynamics/cargo uptake after clathrin (but not AP2 or FCHo1/2) knockdown. Induced membrane curvature enhances CME protein recruitment upon branched actin assembly inhibition under elevated membrane tension. These data establish that membrane curvature assists in CME nucleation and that the essential function of clathrin during CME is to facilitate curvature evolution, rather than scaffold protein recruitment.
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Affiliation(s)
- Robert C. Cail
- Biophysics Graduate Group, University of California Berkeley, Berkeley, CA
| | | | - David G. Drubin
- Biophysics Graduate Group, University of California Berkeley, Berkeley, CA
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA
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20
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OtDUB from the Human Pathogen Orientia tsutsugamushi Modulates Host Membrane Trafficking by Multiple Mechanisms. Mol Cell Biol 2022; 42:e0007122. [PMID: 35727026 PMCID: PMC9302166 DOI: 10.1128/mcb.00071-22] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Host cell membrane-trafficking pathways are often manipulated by bacterial pathogens to gain cell entry, avoid immune responses, or to obtain nutrients. The 1,369-residue OtDUB protein from the obligate intracellular human pathogen Orientia tsutsugamushi bears a deubiquitylase (DUB) and additional domains. Here we show that OtDUB ectopic expression disrupts membrane trafficking through multiple mechanisms. OtDUB binds directly to the clathrin adaptor-protein (AP) complexes AP-1 and AP-2, and the OtDUB275-675 fragment is sufficient for binding to either complex. To assess the impact of OtDUB interactions with AP-1 and AP-2, we examined trans-Golgi trafficking and endocytosis, respectively. Endocytosis is reduced by two separate OtDUB fragments: one contains the AP-binding domain (OtDUB1-675), and the other does not (OtDUB675-1369). OtDUB1-675 disruption of endocytosis requires its ubiquitin-binding capabilities. OtDUB675-1369 also fragments trans- and cis-Golgi structures. Using a growth-based selection in yeast, we identified viable OtDUB675-1369 point mutants that also no longer caused Golgi defects in human cells. In parallel, we found OtDUB675-1369 binds directly to phosphatidylserine, and this lipid binding is lost in the same mutants. Together these results show that OtDUB contains multiple activities capable of modulating membrane trafficking. We discuss how these activities may contribute to Orientia infections.
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21
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Dahhan DA, Reynolds GD, Cárdenas JJ, Eeckhout D, Johnson A, Yperman K, Kaufmann WA, Vang N, Yan X, Hwang I, Heese A, De Jaeger G, Friml J, Van Damme D, Pan J, Bednarek SY. Proteomic characterization of isolated Arabidopsis clathrin-coated vesicles reveals evolutionarily conserved and plant-specific components. THE PLANT CELL 2022; 34:2150-2173. [PMID: 35218346 PMCID: PMC9134090 DOI: 10.1093/plcell/koac071] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 02/22/2022] [Indexed: 05/26/2023]
Abstract
In eukaryotes, clathrin-coated vesicles (CCVs) facilitate the internalization of material from the cell surface as well as the movement of cargo in post-Golgi trafficking pathways. This diversity of functions is partially provided by multiple monomeric and multimeric clathrin adaptor complexes that provide compartment and cargo selectivity. The adaptor-protein assembly polypeptide-1 (AP-1) complex operates as part of the secretory pathway at the trans-Golgi network (TGN), while the AP-2 complex and the TPLATE complex jointly operate at the plasma membrane to execute clathrin-mediated endocytosis. Key to our further understanding of clathrin-mediated trafficking in plants will be the comprehensive identification and characterization of the network of evolutionarily conserved and plant-specific core and accessory machinery involved in the formation and targeting of CCVs. To facilitate these studies, we have analyzed the proteome of enriched TGN/early endosome-derived and endocytic CCVs isolated from dividing and expanding suspension-cultured Arabidopsis (Arabidopsis thaliana) cells. Tandem mass spectrometry analysis results were validated by differential chemical labeling experiments to identify proteins co-enriching with CCVs. Proteins enriched in CCVs included previously characterized CCV components and cargos such as the vacuolar sorting receptors in addition to conserved and plant-specific components whose function in clathrin-mediated trafficking has not been previously defined. Notably, in addition to AP-1 and AP-2, all subunits of the AP-4 complex, but not AP-3 or AP-5, were found to be in high abundance in the CCV proteome. The association of AP-4 with suspension-cultured Arabidopsis CCVs is further supported via additional biochemical data.
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Affiliation(s)
| | | | - Jessica J Cárdenas
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Dominique Eeckhout
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent 9052, Belgium
- VIB Center for Plant Systems Biology, Ghent 9052, Belgium
| | - Alexander Johnson
- Institute of Science and Technology (IST Austria), Klosterneuburg 3400, Austria
| | | | - Walter A Kaufmann
- Institute of Science and Technology (IST Austria), Klosterneuburg 3400, Austria
| | - Nou Vang
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Xu Yan
- College Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Inhwan Hwang
- Department of Life Sciences, Pohang University of Science & Technology, Pohang 37673, Korea
| | - Antje Heese
- Division of Biochemistry, Interdisciplinary Plant Group, University of Missouri-Columbia, Columbia, Missouri 65211, USA
| | - Geert De Jaeger
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent 9052, Belgium
- VIB Center for Plant Systems Biology, Ghent 9052, Belgium
| | - Jiří Friml
- Institute of Science and Technology (IST Austria), Klosterneuburg 3400, Austria
| | - Daniël Van Damme
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent 9052, Belgium
- VIB Center for Plant Systems Biology, Ghent 9052, Belgium
| | - Jianwei Pan
- College Life Sciences, Lanzhou University, Lanzhou 730000, China
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22
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Dahhan DA, Reynolds GD, Cárdenas JJ, Eeckhout D, Johnson A, Yperman K, Kaufmann WA, Vang N, Yan X, Hwang I, Heese A, De Jaeger G, Friml J, Van Damme D, Pan J, Bednarek SY. Proteomic characterization of isolated Arabidopsis clathrin-coated vesicles reveals evolutionarily conserved and plant-specific components. THE PLANT CELL 2022; 34:2150-2173. [PMID: 35218346 DOI: 10.1101/2021.09.16.460678] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Accepted: 02/22/2022] [Indexed: 05/26/2023]
Abstract
In eukaryotes, clathrin-coated vesicles (CCVs) facilitate the internalization of material from the cell surface as well as the movement of cargo in post-Golgi trafficking pathways. This diversity of functions is partially provided by multiple monomeric and multimeric clathrin adaptor complexes that provide compartment and cargo selectivity. The adaptor-protein assembly polypeptide-1 (AP-1) complex operates as part of the secretory pathway at the trans-Golgi network (TGN), while the AP-2 complex and the TPLATE complex jointly operate at the plasma membrane to execute clathrin-mediated endocytosis. Key to our further understanding of clathrin-mediated trafficking in plants will be the comprehensive identification and characterization of the network of evolutionarily conserved and plant-specific core and accessory machinery involved in the formation and targeting of CCVs. To facilitate these studies, we have analyzed the proteome of enriched TGN/early endosome-derived and endocytic CCVs isolated from dividing and expanding suspension-cultured Arabidopsis (Arabidopsis thaliana) cells. Tandem mass spectrometry analysis results were validated by differential chemical labeling experiments to identify proteins co-enriching with CCVs. Proteins enriched in CCVs included previously characterized CCV components and cargos such as the vacuolar sorting receptors in addition to conserved and plant-specific components whose function in clathrin-mediated trafficking has not been previously defined. Notably, in addition to AP-1 and AP-2, all subunits of the AP-4 complex, but not AP-3 or AP-5, were found to be in high abundance in the CCV proteome. The association of AP-4 with suspension-cultured Arabidopsis CCVs is further supported via additional biochemical data.
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Affiliation(s)
- Dana A Dahhan
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Gregory D Reynolds
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Jessica J Cárdenas
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Dominique Eeckhout
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent 9052, Belgium
- VIB Center for Plant Systems Biology, Ghent 9052, Belgium
| | - Alexander Johnson
- Institute of Science and Technology (IST Austria), Klosterneuburg 3400, Austria
| | - Klaas Yperman
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent 9052, Belgium
- VIB Center for Plant Systems Biology, Ghent 9052, Belgium
| | - Walter A Kaufmann
- Institute of Science and Technology (IST Austria), Klosterneuburg 3400, Austria
| | - Nou Vang
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Xu Yan
- College Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Inhwan Hwang
- Department of Life Sciences, Pohang University of Science & Technology, Pohang 37673, Korea
| | - Antje Heese
- Division of Biochemistry, Interdisciplinary Plant Group, University of Missouri-Columbia, Columbia, Missouri 65211, USA
| | - Geert De Jaeger
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent 9052, Belgium
- VIB Center for Plant Systems Biology, Ghent 9052, Belgium
| | - Jiří Friml
- Institute of Science and Technology (IST Austria), Klosterneuburg 3400, Austria
| | - Daniël Van Damme
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent 9052, Belgium
- VIB Center for Plant Systems Biology, Ghent 9052, Belgium
| | - Jianwei Pan
- College Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Sebastian Y Bednarek
- Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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23
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Zaccai NR, Kadlecova Z, Dickson VK, Korobchevskaya K, Kamenicky J, Kovtun O, Umasankar PK, Wrobel AG, Kaufman JGG, Gray SR, Qu K, Evans PR, Fritzsche M, Sroubek F, Höning S, Briggs JAG, Kelly BT, Owen DJ, Traub LM. FCHO controls AP2's initiating role in endocytosis through a PtdIns(4,5)P 2-dependent switch. SCIENCE ADVANCES 2022; 8:eabn2018. [PMID: 35486718 PMCID: PMC9054013 DOI: 10.1126/sciadv.abn2018] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Accepted: 03/11/2022] [Indexed: 06/14/2023]
Abstract
Clathrin-mediated endocytosis (CME) is the main mechanism by which mammalian cells control their cell surface proteome. Proper operation of the pivotal CME cargo adaptor AP2 requires membrane-localized Fer/Cip4 homology domain-only proteins (FCHO). Here, live-cell enhanced total internal reflection fluorescence-structured illumination microscopy shows that FCHO marks sites of clathrin-coated pit (CCP) initiation, which mature into uniform-sized CCPs comprising a central patch of AP2 and clathrin corralled by an FCHO/Epidermal growth factor potential receptor substrate number 15 (Eps15) ring. We dissect the network of interactions between the FCHO interdomain linker and AP2, which concentrates, orients, tethers, and partially destabilizes closed AP2 at the plasma membrane. AP2's subsequent membrane deposition drives its opening, which triggers FCHO displacement through steric competition with phosphatidylinositol 4,5-bisphosphate, clathrin, cargo, and CME accessory factors. FCHO can now relocate toward a CCP's outer edge to engage and activate further AP2s to drive CCP growth/maturation.
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Affiliation(s)
- Nathan R. Zaccai
- CIMR, University of Cambridge, Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Zuzana Kadlecova
- CIMR, University of Cambridge, Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | | | - Kseniya Korobchevskaya
- Kennedy Institute of Rheumatology, University of Oxford, Roosevelt Drive, Oxford OX3 7FY, UK
| | - Jan Kamenicky
- Czech Academy of Sciences, Institute of Information Theory and Automation, Pod Vodarenskou vezi 4, 182 08 Prague 8, Czech Republic
| | - Oleksiy Kovtun
- MRC LMB Cambridge Biomedical Campus, Cambridge CB2 0QH, UK
| | - Perunthottathu K. Umasankar
- Intracellular Trafficking Laboratory, Transdisciplinary Biology Research Program, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, Kerala, India
| | - Antoni G. Wrobel
- CIMR, University of Cambridge, Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | | | - Sally R. Gray
- CIMR, University of Cambridge, Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Kun Qu
- MRC LMB Cambridge Biomedical Campus, Cambridge CB2 0QH, UK
| | | | - Marco Fritzsche
- Kennedy Institute of Rheumatology, University of Oxford, Roosevelt Drive, Oxford OX3 7FY, UK
- Rosalind Franklin Institute, Harwell Campus, Didcot, UK
| | - Filip Sroubek
- Czech Academy of Sciences, Institute of Information Theory and Automation, Pod Vodarenskou vezi 4, 182 08 Prague 8, Czech Republic
| | - Stefan Höning
- Institute for Biochemistry I, Medical Faculty, University of Cologne, Joseph-Stelzmann-Straße 52, 50931 Cologne, Germany
| | - John A. G. Briggs
- MRC LMB Cambridge Biomedical Campus, Cambridge CB2 0QH, UK
- Max Planck Institute of Biochemistry, 82152 Martinsried, Germany
| | - Bernard T. Kelly
- CIMR, University of Cambridge, Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - David J. Owen
- CIMR, University of Cambridge, Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Linton M. Traub
- Department of Cell Biology, University of Pittsburgh School of Medicine, 3500 Terrace Street, Pittsburgh, PA, USA
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24
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Partlow EA, Cannon KS, Hollopeter G, Baker RW. Structural basis of an endocytic checkpoint that primes the AP2 clathrin adaptor for cargo internalization. Nat Struct Mol Biol 2022; 29:339-347. [PMID: 35347313 PMCID: PMC10116491 DOI: 10.1038/s41594-022-00749-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 02/16/2022] [Indexed: 11/08/2022]
Abstract
Clathrin-mediated endocytosis (CME) is the main route of internalization from the plasma membrane. It is known that the heterotetrameric AP2 clathrin adaptor must open to simultaneously engage membrane and endocytic cargo, yet it is unclear how transmembrane cargos are captured to catalyze CME. Using cryogenic-electron microscopy, we discover a new way in which mouse AP2 can reorganize to expose membrane- and cargo-binding pockets, which is not observed in clathrin-coated structures. Instead, it is stimulated by endocytic pioneer proteins called muniscins, which do not enter vesicles. Muniscin-engaged AP2 is primed to rearrange into the vesicle-competent conformation on binding the tyrosine cargo internalization motif (YxxΦ). We propose adaptor priming as a checkpoint to ensure cargo internalization.
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Affiliation(s)
- Edward A Partlow
- Department of Molecular Medicine, Cornell University, Ithaca, NY, USA
| | - Kevin S Cannon
- Department of Biochemistry and Biophysics, University of North Carolina (UNC) Chapel Hill School of Medicine, Chapel Hill, NC, USA
| | | | - Richard W Baker
- Department of Biochemistry and Biophysics, University of North Carolina (UNC) Chapel Hill School of Medicine, Chapel Hill, NC, USA.
- UNC Lineberger Comprehensive Cancer Center, University of North Carolina (UNC) Chapel Hill School of Medicine, Chapel Hill, NC, USA.
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25
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Srinivasan S, Gal J, Bachstetter A, Nelson PT. Alpha adaptins show isoform-specific association with neurofibrillary tangles in Alzheimer's disease. Neuropathol Appl Neurobiol 2022; 48:e12776. [PMID: 34820873 PMCID: PMC8810620 DOI: 10.1111/nan.12776] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2021] [Revised: 11/15/2021] [Accepted: 11/16/2021] [Indexed: 02/06/2023]
Abstract
AIMS The heterotetrameric assembly protein complex 2 (AP-2) is a central hub for clathrin-dependent endocytosis. The AP-2 α-adaptin subunit has two major isoforms, encoded by two separate genes: AP2A1 and AP2A2. Endocytosis has been implicated in the pathogenesis of neurodegenerative disease, and recent studies linked α-adaptins (gene variants, splicing defects and altered expression) with late-onset Alzheimer's disease (LOAD) risk. Here, we used multiple antibodies to investigate α-adaptin isoforms and their localization in human brains. METHODS The specificities of 10 different α-adaptin antibodies were evaluated using immunoblots after human AP2A1 and AP2A2 plasmid transfection in cultured cells. Additional immunoblot analyses were then performed on protein homogenates from control and LOAD subjects. Formalin-fixed, paraffin-embedded brain sections from control and LOAD subjects were immunohistochemically stained, and immunofluorescence experiments were performed for quantitation of colocalisation with digital image analysis. RESULTS Eight of the 10 evaluated antibodies recognised transfected α-adaptin proteins on immunoblots. The α-adaptin subspecies were relatively uniformly expressed in five different human brain regions. The α-adaptins were present in the detergent-insoluble fraction from cognitively impaired, but less so in control, brains. Immunohistochemical analyses showed colocalisation of AP2A1 with tau pathology in LOAD brains. By contrast, AP2A2 colocalised with microglial cells. CONCLUSIONS These observations provide evidence of isoform-specific changes of α-adaptins in the brains of LOAD subjects. Antibodies that were verified to recognise AP2A1, but not AP2A2, labelled neurofibrillary tangles of LOAD patients. The findings extend our understanding of AP-2 proteins in the human brain in healthy and diseased states.
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Affiliation(s)
- Sukanya Srinivasan
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, 40536
| | - Jozsef Gal
- Spinal Cord and Brain Injury Research Center (SCoBIRC), University of Kentucky, Lexington, KY, 40536
- Department of Neuroscience, University of Kentucky, Lexington, KY, 40536
| | - Adam Bachstetter
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, 40536
- Spinal Cord and Brain Injury Research Center (SCoBIRC), University of Kentucky, Lexington, KY, 40536
- Department of Neuroscience, University of Kentucky, Lexington, KY, 40536
| | - Peter T. Nelson
- Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, 40536
- Department of Pathology, University of Kentucky, Lexington, KY, 40536
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26
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Aniento F, Sánchez de Medina Hernández V, Dagdas Y, Rojas-Pierce M, Russinova E. Molecular mechanisms of endomembrane trafficking in plants. THE PLANT CELL 2022; 34:146-173. [PMID: 34550393 PMCID: PMC8773984 DOI: 10.1093/plcell/koab235] [Citation(s) in RCA: 44] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 09/12/2021] [Indexed: 05/10/2023]
Abstract
Endomembrane trafficking is essential for all eukaryotic cells. The best-characterized membrane trafficking organelles include the endoplasmic reticulum (ER), Golgi apparatus, early and recycling endosomes, multivesicular body, or late endosome, lysosome/vacuole, and plasma membrane. Although historically plants have given rise to cell biology, our understanding of membrane trafficking has mainly been shaped by the much more studied mammalian and yeast models. Whereas organelles and major protein families that regulate endomembrane trafficking are largely conserved across all eukaryotes, exciting variations are emerging from advances in plant cell biology research. In this review, we summarize the current state of knowledge on plant endomembrane trafficking, with a focus on four distinct trafficking pathways: ER-to-Golgi transport, endocytosis, trans-Golgi network-to-vacuole transport, and autophagy. We acknowledge the conservation and commonalities in the trafficking machinery across species, with emphasis on diversity and plant-specific features. Understanding the function of organelles and the trafficking machinery currently nonexistent in well-known model organisms will provide great opportunities to acquire new insights into the fundamental cellular process of membrane trafficking.
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Affiliation(s)
| | - Víctor Sánchez de Medina Hernández
- Gregor Mendel Institute, Austrian Academy of Sciences, Vienna BioCenter, 1030 Vienna, Austria
- Vienna BioCenter PhD Program, Doctoral School of the University of Vienna and Medical University of Vienna, A-1030, Vienna, Austria
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27
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Wang B, Yang R, Tian Y, Yin Q. Reconstituting and Purifying Assembly Intermediates of Clathrin Adaptors AP1 and AP2. Methods Mol Biol 2022; 2473:195-212. [PMID: 35819768 DOI: 10.1007/978-1-0716-2209-4_15] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Clathrin-coated vesicles mediate membrane cargo transportation from the plasma membrane, the trans-Golgi network, the endosome, and the lysosome. Heterotetrameric adaptor complexes 1 and 2 (AP1 and AP2) are bridges that link cargo-loaded membranes to clathrin coats. Assembly of AP2 was previously considered to be spontaneous; however, a recent study found AP2 assembly is a highly orchestrated process controlled by alpha and gamma adaptin binding protein (AAGAB). Evidence shows that AAGAB controls AP1 assembly in a similar way. Insights into the orchestrated assembly process and three-dimensional structures of assembly intermediates are only emerging. Here, we describe a protocol for reconstitution and purification of the complexes containing AAGAB and AP1 or AP2 subunits, known as AP1 and AP2 hemicomplexes. Our purification routinely yields milligrams of pure complexes suitable for structural analysis by X-ray crystallography and electron microscopy.
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Affiliation(s)
- Bing Wang
- Department of Biological Science, Florida State University, Tallahassee, FL, USA
| | - Rui Yang
- Department of Biological Science, Florida State University, Tallahassee, FL, USA
| | - Yuan Tian
- Department of Biological Science, Florida State University, Tallahassee, FL, USA
| | - Qian Yin
- Department of Biological Science, Florida State University, Tallahassee, FL, USA.
- Institute of Molecular Biophysics, Florida State University, Tallahassee, FL, USA.
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28
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Law KC, Chung KK, Zhuang X. An Update on Coat Protein Complexes for Vesicle Formation in Plant Post-Golgi Trafficking. FRONTIERS IN PLANT SCIENCE 2022; 13:826007. [PMID: 35283904 PMCID: PMC8905187 DOI: 10.3389/fpls.2022.826007] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 01/11/2022] [Indexed: 05/13/2023]
Abstract
Endomembrane trafficking is an evolutionarily conserved process for all eukaryotic organisms. It is a fundamental and essential process for the transportation of proteins, lipids, or cellular metabolites. The aforementioned cellular components are sorted across multiple membrane-bounded organelles. In plant cells, the endomembrane mainly consists of the nuclear envelope, endoplasmic reticulum (ER), Golgi apparatus, trans-Golgi network or early endosome (TGN/EE), prevacuolar compartments or multivesicular bodies (PVCs/MVBs), and vacuole. Among them, Golgi apparatus and TGN represent two central sorting intermediates for cargo secretion and recycling from other compartments by anterograde or retrograde trafficking. Several protein sorting machineries have been identified to function in these pathways for cargo recognition and vesicle assembly. Exciting progress has been made in recent years to provide novel insights into the sorting complexes and also the underlying sorting mechanisms in plants. Here, we will highlight the recent findings for the adaptor protein (AP) complexes, retromer, and retriever complexes, and also their functions in the related coated vesicle formation in post-Golgi trafficking.
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29
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Graham TR. AP-3 shows off its flexibility for the cryo-EM camera. J Biol Chem 2021; 298:101491. [PMID: 34902351 PMCID: PMC8801477 DOI: 10.1016/j.jbc.2021.101491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/08/2021] [Indexed: 11/29/2022] Open
Abstract
The tetrameric adaptor protein AP-3 is critical for the transport of proteins to lysosomes and lysosome-related organelles. The structures of homologous adaptors AP-1 and AP-2 have revealed a closed-to-open conformational change upon membrane recruitment and phosphoinositide binding. Recently, Schoppe et al. reported the first cryo-EM structures of AP-3 from budding yeast and described remarkably flexible solution structures that are all in the open conformation. The apparent lack of a closed conformational state, the first such description in the literature, allows AP-3 to be more reliant on cargo interaction for its initial membrane recruitment compared with AP-1.
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Affiliation(s)
- Todd R Graham
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA.
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30
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Molecular drivers of tumor progression in microsatellite stable APC mutation-negative colorectal cancers. Sci Rep 2021; 11:23507. [PMID: 34873211 PMCID: PMC8648784 DOI: 10.1038/s41598-021-02806-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 11/18/2021] [Indexed: 12/23/2022] Open
Abstract
The tumor suppressor gene adenomatous polyposis coli (APC) is the initiating mutation in approximately 80% of all colorectal cancers (CRC), underscoring the importance of aberrant regulation of intracellular WNT signaling in CRC development. Recent studies have found that early-onset CRC exhibits an increased proportion of tumors lacking an APC mutation. We set out to identify mechanisms underlying APC mutation-negative (APCmut-) CRCs. We analyzed data from The Cancer Genome Atlas to compare clinical phenotypes, somatic mutations, copy number variations, gene fusions, RNA expression, and DNA methylation profiles between APCmut- and APC mutation-positive (APCmut+) microsatellite stable CRCs. Transcriptionally, APCmut- CRCs clustered into two approximately equal groups. Cluster One was associated with enhanced mitochondrial activation. Cluster Two was strikingly associated with genetic inactivation or decreased RNA expression of the WNT antagonist RNF43, increased expression of the WNT agonist RSPO3, activating mutation of BRAF, or increased methylation and decreased expression of AXIN2. APCmut- CRCs exhibited evidence of increased immune cell infiltration, with significant correlation between M2 macrophages and RSPO3. APCmut- CRCs comprise two groups of tumors characterized by enhanced mitochondrial activation or increased sensitivity to extracellular WNT, suggesting that they could be respectively susceptible to inhibition of these pathways.
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31
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Schoppe J, Schubert E, Apelbaum A, Yavavli E, Birkholz O, Stephanowitz H, Han Y, Perz A, Hofnagel O, Liu F, Piehler J, Raunser S, Ungermann C. Flexible open conformation of the AP-3 complex explains its role in cargo recruitment at the Golgi. J Biol Chem 2021; 297:101334. [PMID: 34688652 PMCID: PMC8591511 DOI: 10.1016/j.jbc.2021.101334] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 09/15/2021] [Accepted: 09/21/2021] [Indexed: 01/17/2023] Open
Abstract
Vesicle formation at endomembranes requires the selective concentration of cargo by coat proteins. Conserved adapter protein complexes at the Golgi (AP-3), the endosome (AP-1), or the plasma membrane (AP-2) with their conserved core domain and flexible ear domains mediate this function. These complexes also rely on the small GTPase Arf1 and/or specific phosphoinositides for membrane binding. The structural details that influence these processes, however, are still poorly understood. Here we present cryo-EM structures of the full-length stable 300 kDa yeast AP-3 complex. The structures reveal that AP-3 adopts an open conformation in solution, comparable to the membrane-bound conformations of AP-1 or AP-2. This open conformation appears to be far more flexible than AP-1 or AP-2, resulting in compact, intermediate, and stretched subconformations. Mass spectrometrical analysis of the cross-linked AP-3 complex further indicates that the ear domains are flexibly attached to the surface of the complex. Using biochemical reconstitution assays, we also show that efficient AP-3 recruitment to the membrane depends primarily on cargo binding. Once bound to cargo, AP-3 clustered and immobilized cargo molecules, as revealed by single-molecule imaging on polymer-supported membranes. We conclude that its flexible open state may enable AP-3 to bind and collect cargo at the Golgi and could thus allow coordinated vesicle formation at the trans-Golgi upon Arf1 activation.
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Affiliation(s)
- Jannis Schoppe
- Department of Biology/Chemistry, Biochemistry Section, Osnabrück University, Osnabrück, Germany
| | - Evelyn Schubert
- Department of Structural Biochemistry, Max-Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Amir Apelbaum
- Department of Structural Biochemistry, Max-Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Erdal Yavavli
- Department of Biology/Chemistry, Biochemistry Section, Osnabrück University, Osnabrück, Germany
| | - Oliver Birkholz
- Department of Biology/Chemistry, Biophysics Section, Osnabrück University, Osnabrück, Germany
| | - Heike Stephanowitz
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Campus Berlin-Buch, Berlin, Germany
| | - Yaping Han
- Department of Biology/Chemistry, Biochemistry Section, Osnabrück University, Osnabrück, Germany
| | - Angela Perz
- Department of Biology/Chemistry, Biochemistry Section, Osnabrück University, Osnabrück, Germany
| | - Oliver Hofnagel
- Department of Structural Biochemistry, Max-Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Fan Liu
- Leibniz-Forschungsinstitut für Molekulare Pharmakologie (FMP), Campus Berlin-Buch, Berlin, Germany
| | - Jacob Piehler
- Department of Biology/Chemistry, Biophysics Section, Osnabrück University, Osnabrück, Germany; Center of Cellular Nanoanalytics Osnabrück (CellNanOs), Osnabrück University, Osnabrück, Germany
| | - Stefan Raunser
- Department of Structural Biochemistry, Max-Planck Institute of Molecular Physiology, Dortmund, Germany.
| | - Christian Ungermann
- Department of Biology/Chemistry, Biochemistry Section, Osnabrück University, Osnabrück, Germany; Center of Cellular Nanoanalytics Osnabrück (CellNanOs), Osnabrück University, Osnabrück, Germany.
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32
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Ramesh ST, Navyasree KV, Sah S, Ashok AB, Qathoon N, Mohanty S, Swain RK, Umasankar PK. BMP2K phosphorylates AP-2 and regulates clathrin-mediated endocytosis. Traffic 2021; 22:377-396. [PMID: 34480404 DOI: 10.1111/tra.12814] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 08/31/2021] [Accepted: 09/01/2021] [Indexed: 01/29/2023]
Abstract
Phosphorylation of the central adaptor protein complex, AP-2 is pivotal for clathrin-mediated endocytosis (CME). Here, we uncover the role of an uncharacterized kinase (BMP-2 inducible kinase-BMP2K) in AP-2 phosphorylation. We demonstrate that BMP2K can phosphorylate AP-2 in vitro and in vivo. Functional impairment of BMP2K impedes AP-2 phosphorylation leading to defects in clathrin-coated pit (CCP) morphology and cargo internalization. BMP2K engages AP-2 via its extended C-terminus and this interaction is important for its CCP localization and function. Notably, endogenous BMP2K levels decline upon functional impairment of AP-2 indicating AP-2 dependent BMP2K stabilization in cells. Further, functional inactivation of BMP2K in zebrafish embryos yields gastrulation phenotypes which mirror AP-2 loss-of-function suggesting physiological relevance of BMP2K in vertebrates. Together, our findings propose involvement of a novel kinase in AP-2 phosphorylation and in the operation of CME.
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Affiliation(s)
- Shikha T Ramesh
- Intracellular Trafficking Laboratory, Transdisciplinary Biology Research Program, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, Kerala, India.,Centre for Doctoral Studies, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Kolaparamba V Navyasree
- Intracellular Trafficking Laboratory, Transdisciplinary Biology Research Program, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, Kerala, India.,Centre for Doctoral Studies, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Sneha Sah
- Intracellular Trafficking Laboratory, Transdisciplinary Biology Research Program, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, Kerala, India
| | - Anjitha B Ashok
- Intracellular Trafficking Laboratory, Transdisciplinary Biology Research Program, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, Kerala, India
| | - Nishada Qathoon
- Intracellular Trafficking Laboratory, Transdisciplinary Biology Research Program, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, Kerala, India
| | | | | | - Perunthottathu K Umasankar
- Intracellular Trafficking Laboratory, Transdisciplinary Biology Research Program, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram, Kerala, India
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33
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Watkins JM, Ross-Elliott TJ, Shan X, Lou F, Dreyer B, Tunc-Ozdemir M, Jia H, Yang J, Oliveira CC, Wu L, Trusov Y, Schwochert TD, Krysan P, Jones AM. Differential regulation of G protein signaling in Arabidopsis through two distinct pathways that internalize AtRGS1. Sci Signal 2021; 14:14/695/eabe4090. [PMID: 34376571 DOI: 10.1126/scisignal.abe4090] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In animals, endocytosis of a seven-transmembrane GPCR is mediated by arrestins to propagate or arrest cytoplasmic G protein-mediated signaling, depending on the bias of the receptor or ligand, which determines how much one transduction pathway is used compared to another. In Arabidopsis thaliana, GPCRs are not required for G protein-coupled signaling because the heterotrimeric G protein complex spontaneously exchanges nucleotide. Instead, the seven-transmembrane protein AtRGS1 modulates G protein signaling through ligand-dependent endocytosis, which initiates derepression of signaling without the involvement of canonical arrestins. Here, we found that endocytosis of AtRGS1 initiated from two separate pools of plasma membrane: sterol-dependent domains and a clathrin-accessible neighborhood, each with a select set of discriminators, activators, and candidate arrestin-like adaptors. Ligand identity (either the pathogen-associated molecular pattern flg22 or the sugar glucose) determined the origin of AtRGS1 endocytosis. Different trafficking origins and trajectories led to different cellular outcomes. Thus, in this system, compartmentation with its associated signalosome architecture drives biased signaling.
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Affiliation(s)
- Justin M Watkins
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Timothy J Ross-Elliott
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Xiaoyi Shan
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Fei Lou
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Bernd Dreyer
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Meral Tunc-Ozdemir
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Haiyan Jia
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Jing Yang
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Celio Cabral Oliveira
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.,Department of Biochemistry and Molecular Biology/Bioagro, Universidade Federal de Viçosa, Viçosa, MG, Brazil
| | - Luguang Wu
- School of Agriculture and Food Science, University of Queensland, St. Lucia, Queensland Q4072, Australia
| | - Yuri Trusov
- School of Agriculture and Food Science, University of Queensland, St. Lucia, Queensland Q4072, Australia
| | - Timothy D Schwochert
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Patrick Krysan
- Department of Horticulture, University of Wisconsin Madison, Madison, WI 53706, USA
| | - Alan M Jones
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA. .,Department of Pharmacology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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Redlingshöfer L, Brodsky FM. Antagonistic regulation controls clathrin-mediated endocytosis: AP2 adaptor facilitation vs restraint from clathrin light chains. Cells Dev 2021; 168:203714. [PMID: 34182181 DOI: 10.1016/j.cdev.2021.203714] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 06/11/2021] [Accepted: 06/21/2021] [Indexed: 02/02/2023]
Abstract
Orchestration of a complex network of protein interactions drives clathrin-mediated endocytosis (CME). A central role for the AP2 adaptor complex beyond cargo recognition and clathrin recruitment has emerged in recent years. It is now apparent that AP2 serves as a pivotal hub for protein interactions to mediate clathrin coated pit maturation, and couples lattice formation to membrane deformation. As a key driver for clathrin assembly, AP2 complements the attenuating role of clathrin light chain subunits, which enable dynamic lattice rearrangement needed for budding. This review summarises recent insights into AP2 function with respect to CME dynamics and biophysics, and its relationship to the role of clathrin light chains in clathrin assembly.
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Affiliation(s)
- Lisa Redlingshöfer
- Research Department of Structural and Molecular Biology, Division of Biosciences, University College London, Gower Street, London WC1E 6BT, United Kingdom; Institute for Structural and Molecular Biology, Birkbeck and University College London, London WC1E 7HX, United Kingdom.
| | - Frances M Brodsky
- Research Department of Structural and Molecular Biology, Division of Biosciences, University College London, Gower Street, London WC1E 6BT, United Kingdom; Institute for Structural and Molecular Biology, Birkbeck and University College London, London WC1E 7HX, United Kingdom.
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35
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Viral Interactions with Adaptor-Protein Complexes: A Ubiquitous Trait among Viral Species. Int J Mol Sci 2021; 22:ijms22105274. [PMID: 34067854 PMCID: PMC8156722 DOI: 10.3390/ijms22105274] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/10/2021] [Accepted: 05/12/2021] [Indexed: 12/22/2022] Open
Abstract
Numerous viruses hijack cellular protein trafficking pathways to mediate cell entry or to rearrange membrane structures thereby promoting viral replication and antagonizing the immune response. Adaptor protein complexes (AP), which mediate protein sorting in endocytic and secretory transport pathways, are one of the conserved viral targets with many viruses possessing AP-interacting motifs. We present here different mechanisms of viral interference with AP complexes and the functional consequences that allow for efficient viral propagation and evasion of host immune defense. The ubiquity of this phenomenon is evidenced by the fact that there are representatives for AP interference in all major viral families, covered in this review. The best described examples are interactions of human immunodeficiency virus and human herpesviruses with AP complexes. Several other viruses, like Ebola, Nipah, and SARS-CoV-2, are pointed out as high priority disease-causative agents supporting the need for deeper understanding of virus-AP interplay which can be exploited in the design of novel antiviral therapies.
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36
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Mishra R, Sengül GF, Candiello E, Schu P. Synaptic AP2 CCV life cycle regulation by the Eps15, ITSN1, Sgip1/AP2, synaptojanin1 interactome. Sci Rep 2021; 11:8007. [PMID: 33850201 PMCID: PMC8044098 DOI: 10.1038/s41598-021-87591-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Accepted: 03/30/2021] [Indexed: 11/18/2022] Open
Abstract
The AP1/σ1B knockout causes impaired synaptic vesicle recycling and enhanced protein sorting into endosomes, leading to severe intellectual disability. These disturbances in synaptic protein sorting induce as a secondary phenotype the upregulation of AP2 CCV mediated endocytosis. Synapses contain canonical AP2 CCV and AP2 CCV with a more stable coat and thus extended life time. In AP1/σ1B knockout synapses, pool sizes of both CCV classes are doubled. Additionally, stable CCV of the knockout are more stabilised than stable wt CCV. One mechanism responsible for enhanced CCV stabilisation is the reduction of synaptojanin1 CCV levels, the PI-4,5-P2 phosphatase essential for AP2 membrane dissociation. To identify mechanisms regulating synaptojanin1 recruitment, we compared synaptojanin1 CCV protein interactome levels and CCV protein interactions between both CCV classes from wt and knockout mice. We show that ITSN1 determines synaptojanin1 CCV levels. Sgip1/AP2 excess hinders synaptojanin1 binding to ITSN1, further lowering its levels. ITSN1 levels are determined by Eps15, not Eps15L1. In addition, the data reveal that reduced amounts of pacsin1 can be counter balanced by its enhanced activation. These data exemplify the complexity of CCV life cycle regulation and indicate how cargo proteins determine the life cycle of their CCV.
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Affiliation(s)
- R Mishra
- Department of Cellular Biochemistry, University Medical Center, Georg-August University Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
- Department of Clinical Neurosciences, John Van Geest Centre for Brain Repair, University of Cambridge, Cambridge, England, UK
| | - G F Sengül
- Department of Cellular Biochemistry, University Medical Center, Georg-August University Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
| | - E Candiello
- Department of Cellular Biochemistry, University Medical Center, Georg-August University Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
- Institute for Cancer Research and Treatment (IRCC), Turin, Italy
| | - P Schu
- Department of Cellular Biochemistry, University Medical Center, Georg-August University Göttingen, Humboldtallee 23, 37073, Göttingen, Germany.
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37
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Hannan FM, Stevenson M, Bayliss AL, Stokes VJ, Stewart M, Kooblall KG, Gorvin CM, Codner G, Teboul L, Wells S, Thakker RV. Ap2s1 mutation causes hypercalcaemia in mice and impairs interaction between calcium-sensing receptor and adaptor protein-2. Hum Mol Genet 2021; 30:880-892. [PMID: 33729479 PMCID: PMC8165646 DOI: 10.1093/hmg/ddab076] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 02/09/2021] [Accepted: 02/26/2021] [Indexed: 12/16/2022] Open
Abstract
Adaptor protein 2 (AP2), a heterotetrameric complex comprising AP2α, AP2β2, AP2μ2 and AP2σ2 subunits, is ubiquitously expressed and involved in endocytosis and trafficking of membrane proteins, such as the calcium-sensing receptor (CaSR), a G-protein coupled receptor that signals via Gα11. Mutations of CaSR, Gα11 and AP2σ2, encoded by AP2S1, cause familial hypocalciuric hypercalcaemia types 1–3 (FHH1–3), respectively. FHH3 patients have heterozygous AP2S1 missense Arg15 mutations (p.Arg15Cys, p.Arg15His or p.Arg15Leu) with hypercalcaemia, which may be marked and symptomatic, and occasional hypophosphataemia and osteomalacia. To further characterize the phenotypic spectrum and calcitropic pathophysiology of FHH3, we used CRISPR/Cas9 genome editing to generate mice harboring the AP2S1 p.Arg15Leu mutation, which causes the most severe FHH3 phenotype. Heterozygous (Ap2s1+/L15) mice were viable, and had marked hypercalcaemia, hypermagnesaemia, hypophosphataemia, and increases in alkaline phosphatase activity and fibroblast growth factor-23. Plasma 1,25-dihydroxyvitamin D was normal, and no alterations in bone mineral density or bone turnover were noted. Homozygous (Ap2s1L15/L15) mice invariably died perinatally. Co-immunoprecipitation studies showed that the AP2S1 p.Arg15Leu mutation impaired protein–protein interactions between AP2σ2 and the other AP2 subunits, and also with the CaSR. Cinacalcet, a CaSR positive allosteric modulator, decreased plasma calcium and parathyroid hormone concentrations in Ap2s1+/L15 mice, but had no effect on the diminished AP2σ2-CaSR interaction in vitro. Thus, our studies have established a mouse model that is representative for FHH3 in humans, and demonstrated that the AP2S1 p.Arg15Leu mutation causes a predominantly calcitropic phenotype, which can be ameliorated by treatment with cinacalcet.
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Affiliation(s)
- Fadil M Hannan
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7LJ, UK.,Nuffield Department of Women's and Reproductive Health, University of Oxford, Oxford OX3 9DU, UK
| | - Mark Stevenson
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7LJ, UK
| | - Asha L Bayliss
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7LJ, UK
| | - Victoria J Stokes
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7LJ, UK
| | - Michelle Stewart
- Mammalian Genetics Unit and Mary Lyon Centre, MRC Harwell Institute, Harwell Campus, Oxfordshire OX11 0RD, UK
| | - Kreepa G Kooblall
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7LJ, UK
| | - Caroline M Gorvin
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7LJ, UK
| | - Gemma Codner
- Mammalian Genetics Unit and Mary Lyon Centre, MRC Harwell Institute, Harwell Campus, Oxfordshire OX11 0RD, UK
| | - Lydia Teboul
- Mammalian Genetics Unit and Mary Lyon Centre, MRC Harwell Institute, Harwell Campus, Oxfordshire OX11 0RD, UK
| | - Sara Wells
- Mammalian Genetics Unit and Mary Lyon Centre, MRC Harwell Institute, Harwell Campus, Oxfordshire OX11 0RD, UK
| | - Rajesh V Thakker
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford OX3 7LJ, UK
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38
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Zhu C, Zhou X, Liu Z, Chen H, Wu H, Yang X, Zhu X, Ma J, Dong H. The Morphology of Hydroxyapatite Nanoparticles Regulates Cargo Recognition in Clathrin-Mediated Endocytosis. Front Mol Biosci 2021; 8:627015. [PMID: 33748189 PMCID: PMC7969717 DOI: 10.3389/fmolb.2021.627015] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Accepted: 01/15/2021] [Indexed: 01/06/2023] Open
Abstract
The clathrin-associated protein adaptin-2 (AP2) is a distinctive member of the hetero-tetrameric clathrin adaptor complex family. It plays a crucial role in many intracellular vesicle transport pathways. The hydroxyapatite (HAp) nanoparticles can enter cells through clathrin-dependent endocytosis, induce apoptosis, and ultimately inhibit tumor metastasis. Exploring the micro process of the binding of AP2 and HAp is of great significance for understanding the molecular mechanism of HAp's anti-cancer ability. In this work, we used molecular modeling to study the binding of spherical, rod-shaped, and needle-shaped HAps toward AP2 protein at the atomic level and found that different nanoparticles' morphology can determine their binding specificity through electrostatic interactions. Our results show that globular HAp significantly changes AP2 protein conformation, while needle-shaped HAP has more substantial binding energy with AP2. Therefore, this work offers a microscopic picture for cargo recognition in clathrin-mediated endocytosis, clarifies the design principles and possible mechanisms of high-efficiency nano-biomaterials, and provides a basis for their potential anti-tumor therapeutic effects.
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Affiliation(s)
- Cheng Zhu
- Kuang Yaming Honors School, Nanjing University, Nanjing, China
- Tianjin Key Laboratory of Function and Application of Biological Macromolecular Structures, School of Life Sciences, Tianjin University, Tianjin, China
| | - Xuejie Zhou
- Kuang Yaming Honors School, Nanjing University, Nanjing, China
| | - Ziteng Liu
- Key Laboratory of Mesoscopic Chemistry of Ministry of Education, Institute of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, China
| | - Hongwei Chen
- Key Laboratory of Mesoscopic Chemistry of Ministry of Education, Institute of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, China
| | - Hongfeng Wu
- National Engineering Research Center for Biomaterials, Sichuan University, Chengdu, China
| | - Xiao Yang
- National Engineering Research Center for Biomaterials, Sichuan University, Chengdu, China
| | - Xiangdong Zhu
- National Engineering Research Center for Biomaterials, Sichuan University, Chengdu, China
| | - Jing Ma
- Key Laboratory of Mesoscopic Chemistry of Ministry of Education, Institute of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, China
- Nanxin Pharm. Co., Ltd., Nanjing, China
| | - Hao Dong
- Kuang Yaming Honors School, Nanjing University, Nanjing, China
- Nanxin Pharm. Co., Ltd., Nanjing, China
- Institute for Brain Sciences, Nanjing University, Nanjing, China
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39
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Hirst J, Hesketh GG, Gingras AC, Robinson MS. Rag GTPases and phosphatidylinositol 3-phosphate mediate recruitment of the AP-5/SPG11/SPG15 complex. J Cell Biol 2021; 220:211690. [PMID: 33464297 PMCID: PMC7814351 DOI: 10.1083/jcb.202002075] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 05/21/2020] [Accepted: 12/02/2020] [Indexed: 12/31/2022] Open
Abstract
Adaptor protein complex 5 (AP-5) and its partners, SPG11 and SPG15, are recruited onto late endosomes and lysosomes. Here we show that recruitment of AP-5/SPG11/SPG15 is enhanced in starved cells and occurs by coincidence detection, requiring both phosphatidylinositol 3-phosphate (PI3P) and Rag GTPases. PI3P binding is via the SPG15 FYVE domain, which, on its own, localizes to early endosomes. GDP-locked RagC promotes recruitment of AP-5/SPG11/SPG15, while GTP-locked RagA prevents its recruitment. Our results uncover an interplay between AP-5/SPG11/SPG15 and the mTORC1 pathway and help to explain the phenotype of AP-5/SPG11/SPG15 deficiency in patients, including the defect in autophagic lysosome reformation.
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Affiliation(s)
- Jennifer Hirst
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK,Jennifer Hirst:
| | - Geoffrey G. Hesketh
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, Ontario, Canada
| | - Anne-Claude Gingras
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, Ontario, Canada,Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Margaret S. Robinson
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK,Correspondence to Margaret S. Robinson:
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40
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Bhave M, Mino RE, Wang X, Lee J, Grossman HM, Lakoduk AM, Danuser G, Schmid SL, Mettlen M. Functional characterization of 67 endocytic accessory proteins using multiparametric quantitative analysis of CCP dynamics. Proc Natl Acad Sci U S A 2020; 117:31591-31602. [PMID: 33257546 PMCID: PMC7749282 DOI: 10.1073/pnas.2020346117] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Clathrin-mediated endocytosis (CME) begins with the nucleation of clathrin assembly on the plasma membrane, followed by stabilization and growth/maturation of clathrin-coated pits (CCPs) that eventually pinch off and internalize as clathrin-coated vesicles. This highly regulated process involves a myriad of endocytic accessory proteins (EAPs), many of which are multidomain proteins that encode a wide range of biochemical activities. Although domain-specific activities of EAPs have been extensively studied, their precise stage-specific functions have been identified in only a few cases. Using single-guide RNA (sgRNA)/dCas9 and small interfering RNA (siRNA)-mediated protein knockdown, combined with an image-based analysis pipeline, we have determined the phenotypic signature of 67 EAPs throughout the maturation process of CCPs. Based on these data, we show that EAPs can be partitioned into phenotypic clusters, which differentially affect CCP maturation and dynamics. Importantly, these clusters do not correlate with functional modules based on biochemical activities. Furthermore, we discover a critical role for SNARE proteins and their adaptors during early stages of CCP nucleation and stabilization and highlight the importance of GAK throughout CCP maturation that is consistent with GAK's multifunctional domain architecture. Together, these findings provide systematic, mechanistic insights into the plasticity and robustness of CME.
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Affiliation(s)
- Madhura Bhave
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Rosa E Mino
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Xinxin Wang
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
- Lyda Hill Department of Bioinformatics, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Jeon Lee
- Lyda Hill Department of Bioinformatics, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Heather M Grossman
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
- Lyda Hill Department of Bioinformatics, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Ashley M Lakoduk
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Gaudenz Danuser
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
- Lyda Hill Department of Bioinformatics, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Sandra L Schmid
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390;
| | - Marcel Mettlen
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390;
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41
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A trimeric Rab7 GEF controls NPC1-dependent lysosomal cholesterol export. Nat Commun 2020; 11:5559. [PMID: 33144569 PMCID: PMC7642327 DOI: 10.1038/s41467-020-19032-0] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 09/18/2020] [Indexed: 12/26/2022] Open
Abstract
Cholesterol import in mammalian cells is mediated by the LDL receptor pathway. Here, we perform a genome-wide CRISPR screen using an endogenous cholesterol reporter and identify >100 genes involved in LDL-cholesterol import. We characterise C18orf8 as a core subunit of the mammalian Mon1-Ccz1 guanidine exchange factor (GEF) for Rab7, required for complex stability and function. C18orf8-deficient cells lack Rab7 activation and show severe defects in late endosome morphology and endosomal LDL trafficking, resulting in cellular cholesterol deficiency. Unexpectedly, free cholesterol accumulates within swollen lysosomes, suggesting a critical defect in lysosomal cholesterol export. We find that active Rab7 interacts with the NPC1 cholesterol transporter and licenses lysosomal cholesterol export. This process is abolished in C18orf8-, Ccz1- and Mon1A/B-deficient cells and restored by a constitutively active Rab7. The trimeric Mon1-Ccz1-C18orf8 (MCC) GEF therefore plays a central role in cellular cholesterol homeostasis coordinating Rab7 activation, endosomal LDL trafficking and NPC1-dependent lysosomal cholesterol export. Lysosomes play an important role in cellular LDL-cholesterol uptake. Here, the authors perform a genome-wide genetic screen for cholesterol regulators and identify C18orf8 as a conserved subunit of a trimeric Rab7 GEF that controls LDL trafficking and NPC1-dependent lysosomal cholesterol export.
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42
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Schoppe J, Mari M, Yavavli E, Auffarth K, Cabrera M, Walter S, Fröhlich F, Ungermann C. AP-3 vesicle uncoating occurs after HOPS-dependent vacuole tethering. EMBO J 2020; 39:e105117. [PMID: 32840906 PMCID: PMC7560216 DOI: 10.15252/embj.2020105117] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 07/16/2020] [Accepted: 07/22/2020] [Indexed: 11/09/2022] Open
Abstract
Heterotetrameric adapter (AP) complexes cooperate with the small GTPase Arf1 or lipids in cargo selection, vesicle formation, and budding at endomembranes in eukaryotic cells. While most AP complexes also require clathrin as the outer vesicle shell, formation of AP-3-coated vesicles involved in Golgi-to-vacuole transport in yeast has been postulated to depend on Vps41, a subunit of the vacuolar HOPS tethering complex. HOPS has also been identified as the tether of AP-3 vesicles on vacuoles. To unravel this conundrum of a dual Vps41 function, we anchored Vps41 stably to the mitochondrial outer membrane. By monitoring AP-3 recruitment, we now show that Vps41 can tether AP-3 vesicles to mitochondria, yet AP-3 vesicles can form in the absence of Vps41 or clathrin. By proximity labeling and mass spectrometry, we identify the Arf1 GTPase-activating protein (GAP) Age2 at the AP-3 coat and show that tethering, but not fusion at the vacuole can occur without complete uncoating. We conclude that AP-3 vesicles retain their coat after budding and that their complete uncoating occurs only after tethering at the vacuole.
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Affiliation(s)
- Jannis Schoppe
- Department of Biology/Chemistry, Biochemistry Section, University of Osnabrück, Osnabrück, Germany
| | - Muriel Mari
- Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Erdal Yavavli
- Department of Biology/Chemistry, Biochemistry Section, University of Osnabrück, Osnabrück, Germany
| | - Kathrin Auffarth
- Department of Biology/Chemistry, Biochemistry Section, University of Osnabrück, Osnabrück, Germany
| | - Margarita Cabrera
- Departament de Ciències Experimentals i de la Salut, Universitat Pompeu Farba, Barcelona, Spain
| | - Stefan Walter
- Center of Cellular Nanoanalytic Osnabrück (CellNanOs), University of Osnabrück, Osnabrück, Germany
| | - Florian Fröhlich
- Center of Cellular Nanoanalytic Osnabrück (CellNanOs), University of Osnabrück, Osnabrück, Germany.,Department of Biology/Chemistry, Molecular Membrane Biology Section, University of Osnabrück, Osnabrück, Germany
| | - Christian Ungermann
- Department of Biology/Chemistry, Biochemistry Section, University of Osnabrück, Osnabrück, Germany.,Center of Cellular Nanoanalytic Osnabrück (CellNanOs), University of Osnabrück, Osnabrück, Germany
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43
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Yong XLH, Cousin MA, Anggono V. PICK1 Controls Activity-Dependent Synaptic Vesicle Cargo Retrieval. Cell Rep 2020; 33:108312. [PMID: 33113376 DOI: 10.1016/j.celrep.2020.108312] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 09/03/2020] [Accepted: 10/05/2020] [Indexed: 12/23/2022] Open
Abstract
Efficient retrieval of synaptic vesicles (SVs) is crucial to sustain synaptic transmission. Protein interacting with C-kinase 1 (PICK1) is a unique PDZ (postsynaptic density-95/disc-large/zona-occluden-1)- and BAR (Bin-Amphiphysin-Rvs )-domain-containing protein that regulates the trafficking of postsynaptic glutamate receptors. It is also expressed in presynaptic terminals and is associated with the SVs; however, its role in regulating SV recycling remains unknown. Here, we show that PICK1 loss of function selectively slows the kinetics of SV endocytosis in primary hippocampal neurons during high-frequency stimulation. PICK1 knockdown also causes surface stranding and mislocalization of major SV proteins, synaptophysin and vGlut1, along the axon. A functional PDZ domain of PICK1 and its interaction with the core endocytic adaptor protein (AP)-2 are required for the proper targeting and clustering of synaptophysin. Furthermore, PICK1 and its interaction with AP-2 are required for efficient SV endocytosis and sustained glutamate release. Our findings, therefore, identify PICK1 as a key regulator of presynaptic vesicle recycling in central synapses.
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Affiliation(s)
- Xuan Ling Hilary Yong
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Michael A Cousin
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh EH8 9XD, Scotland, UK; Muir Maxwell Epilepsy Centre, University of Edinburgh, Edinburgh EH8 9XD, Scotland, UK; Simons Initiative for the Developing Brain, University of Edinburgh, Edinburgh EH8 9XD, Scotland, UK
| | - Victor Anggono
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia.
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44
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Chen Z, Schmid SL. Evolving models for assembling and shaping clathrin-coated pits. J Cell Biol 2020; 219:e202005126. [PMID: 32770195 PMCID: PMC7480099 DOI: 10.1083/jcb.202005126] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 07/13/2020] [Accepted: 07/13/2020] [Indexed: 01/01/2023] Open
Abstract
Clathrin-mediated endocytosis occurs via the assembly of clathrin-coated pits (CCPs) that invaginate and pinch off to form clathrin-coated vesicles (CCVs). It is well known that adaptor protein 2 (AP2) complexes trigger clathrin assembly on the plasma membrane, and biochemical and structural studies have revealed the nature of these interactions. Numerous endocytic accessory proteins collaborate with clathrin and AP2 to drive CCV formation. However, many questions remain as to the molecular events involved in CCP initiation, stabilization, and curvature generation. Indeed, a plethora of recent evidence derived from cell perturbation, correlative light and EM tomography, live-cell imaging, modeling, and high-resolution structural analyses has revealed more complexity and promiscuity in the protein interactions driving CCP maturation than anticipated. After briefly reviewing the evidence supporting prevailing models, we integrate these new lines of evidence to develop a more dynamic and flexible model for how redundant, dynamic, and competing protein interactions can drive endocytic CCV formation and suggest new approaches to test emerging models.
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Affiliation(s)
| | - Sandra L. Schmid
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX
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45
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Kwon Y, Kaake RM, Echeverria I, Suarez M, Karimian Shamsabadi M, Stoneham C, Ramirez PW, Kress J, Singh R, Sali A, Krogan N, Guatelli J, Jia X. Structural basis of CD4 downregulation by HIV-1 Nef. Nat Struct Mol Biol 2020; 27:822-828. [PMID: 32719457 PMCID: PMC7483821 DOI: 10.1038/s41594-020-0463-z] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 06/16/2020] [Indexed: 02/06/2023]
Abstract
The HIV-1 Nef protein suppresses multiple immune surveillance mechanisms to promote viral pathogenesis and is an attractive target for the development of novel therapeutics. A key function of Nef is to remove the CD4 receptor from the cell surface by hijacking clathrin- and adaptor protein complex 2 (AP2)-dependent endocytosis. However, exactly how Nef does this has been elusive. Here, we describe the underlying mechanism as revealed by a 3.0-Å crystal structure of a fusion protein comprising Nef and the cytoplasmic domain of CD4 bound to the tetrameric AP2 complex. An intricate combination of conformational changes occurs in both Nef and AP2 to enable CD4 binding and downregulation. A pocket on Nef previously identified as crucial for recruiting class I MHC is also responsible for recruiting CD4, revealing a potential approach to inhibit two of Nef's activities and sensitize the virus to immune clearance.
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Affiliation(s)
- Yonghwa Kwon
- Department of Chemistry and Biochemistry, University of Massachusetts Dartmouth, Dartmouth, MA, USA
| | - Robyn M Kaake
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA, USA
- Gladstone Institutes, San Francisco, CA, USA
| | - Ignacia Echeverria
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, CA, USA
| | | | | | - Charlotte Stoneham
- The VA San Diego Healthcare System, San Diego, CA, USA
- Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Peter W Ramirez
- Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Jacob Kress
- Department of Chemistry and Biochemistry, University of Massachusetts Dartmouth, Dartmouth, MA, USA
| | - Rajendra Singh
- The VA San Diego Healthcare System, San Diego, CA, USA
- Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Andrej Sali
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, CA, USA
- Department of Pharmaceutical Chemistry and Quantitative Biosciences Institute, University of California, San Francisco, San Francisco, CA, USA
| | - Nevan Krogan
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA, USA
- Gladstone Institutes, San Francisco, CA, USA
| | - John Guatelli
- The VA San Diego Healthcare System, San Diego, CA, USA
- Department of Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Xiaofei Jia
- Department of Chemistry and Biochemistry, University of Massachusetts Dartmouth, Dartmouth, MA, USA.
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46
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Redpath GMI, Betzler VM, Rossatti P, Rossy J. Membrane Heterogeneity Controls Cellular Endocytic Trafficking. Front Cell Dev Biol 2020; 8:757. [PMID: 32850860 PMCID: PMC7419583 DOI: 10.3389/fcell.2020.00757] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Accepted: 07/20/2020] [Indexed: 12/21/2022] Open
Abstract
Endocytic trafficking relies on highly localized events in cell membranes. Endocytosis involves the gathering of protein (cargo/receptor) at distinct plasma membrane locations defined by specific lipid and protein compositions. Simultaneously, the molecular machinery that drives invagination and eventually scission of the endocytic vesicle assembles at the very same place on the inner leaflet of the membrane. It is membrane heterogeneity - the existence of specific lipid and protein domains in localized regions of membranes - that creates the distinct molecular identity required for an endocytic event to occur precisely when and where it is required rather than at some random location within the plasma membrane. Accumulating evidence leads us to believe that the trafficking fate of internalized proteins is sealed following endocytosis, as this distinct membrane identity is preserved through the endocytic pathway, upon fusion of endocytic vesicles with early and sorting endosomes. In fact, just like at the plasma membrane, multiple domains coexist at the surface of these endosomes, regulating local membrane tubulation, fission and sorting to recycling pathways or to the trans-Golgi network via late endosomes. From here, membrane heterogeneity ensures that fusion events between intracellular vesicles and larger compartments are spatially regulated to promote the transport of cargoes to their intracellular destination.
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Affiliation(s)
- Gregory M I Redpath
- Department of Biochemistry, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand.,The ANZAC Research Institute, Concord Repatriation General Hospital, Concord, NSW, Australia
| | - Verena M Betzler
- Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland.,Biotechnology Institute Thurgau (BITg) at the University of Konstanz, Kreuzlingen, Switzerland
| | - Pascal Rossatti
- Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland.,Biotechnology Institute Thurgau (BITg) at the University of Konstanz, Kreuzlingen, Switzerland
| | - Jérémie Rossy
- Biotechnology Institute Thurgau (BITg) at the University of Konstanz, Kreuzlingen, Switzerland.,Department of Biology, University of Konstanz, Konstanz, Germany
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47
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Yuan S, Chu H, Huang J, Zhao X, Ye ZW, Lai PM, Wen L, Cai JP, Mo Y, Cao J, Liang R, Poon VKM, Sze KH, Zhou J, To KKW, Chen Z, Chen H, Jin DY, Chan JFW, Yuen KY. Viruses harness YxxØ motif to interact with host AP2M1 for replication: A vulnerable broad-spectrum antiviral target. SCIENCE ADVANCES 2020; 6:eaba7910. [PMID: 32923629 PMCID: PMC7455044 DOI: 10.1126/sciadv.aba7910] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2020] [Accepted: 07/14/2020] [Indexed: 05/24/2023]
Abstract
Targeting a universal host protein exploited by most viruses would be a game-changing strategy that offers broad-spectrum solution and rapid pandemic control including the current COVID-19. Here, we found a common YxxØ-motif of multiple viruses that exploits host AP2M1 for intracellular trafficking. A library chemical, N-(p-amylcinnamoyl)anthranilic acid (ACA), was identified to interrupt AP2M1-virus interaction and exhibit potent antiviral efficacy against a number of viruses in vitro and in vivo, including the influenza A viruses (IAVs), Zika virus (ZIKV), human immunodeficiency virus, and coronaviruses including MERS-CoV and SARS-CoV-2. YxxØ mutation, AP2M1 depletion, or disruption by ACA causes incorrect localization of viral proteins, which is exemplified by the failure of nuclear import of IAV nucleoprotein and diminished endoplasmic reticulum localization of ZIKV-NS3 and enterovirus-A71-2C proteins, thereby suppressing viral replication. Our study reveals an evolutionarily conserved mechanism of protein-protein interaction between host and virus that can serve as a broad-spectrum antiviral target.
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MESH Headings
- A549 Cells
- Adaptor Proteins, Vesicular Transport/metabolism
- Animals
- Antiviral Agents/pharmacology
- Betacoronavirus/drug effects
- Binding Sites/genetics
- COVID-19
- Cell Line, Tumor
- Chlorocebus aethiops
- Cinnamates/pharmacology
- Coronavirus Infections/drug therapy
- Coronavirus Infections/pathology
- Dogs
- HEK293 Cells
- HIV Infections/drug therapy
- HIV Infections/pathology
- HIV-1/drug effects
- Host-Pathogen Interactions/drug effects
- Humans
- Influenza A virus/drug effects
- Influenza, Human/drug therapy
- Influenza, Human/pathology
- Madin Darby Canine Kidney Cells
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Knockout
- Middle East Respiratory Syndrome Coronavirus/drug effects
- Pandemics
- Pneumonia, Viral/drug therapy
- Pneumonia, Viral/pathology
- Protein Binding/genetics
- Protein Transport/drug effects
- RNA, Viral/genetics
- Receptor, Interferon alpha-beta/genetics
- SARS-CoV-2
- Transforming Growth Factor beta1/metabolism
- Vero Cells
- Virus Replication/drug effects
- Zika Virus/drug effects
- Zika Virus Infection/pathology
- ortho-Aminobenzoates/pharmacology
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Affiliation(s)
- Shuofeng Yuan
- State Key Laboratory of Emerging Infectious Diseases, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- Carol Yu Centre for Infection, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- Department of Clinical Microbiology and Infection Control, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Hin Chu
- State Key Laboratory of Emerging Infectious Diseases, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- Carol Yu Centre for Infection, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- Department of Clinical Microbiology and Infection Control, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Jingjing Huang
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
| | - Xiaoyu Zhao
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
| | - Zi-Wei Ye
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
| | - Pok-Man Lai
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
| | - Lei Wen
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
| | - Jian-Piao Cai
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
| | - Yufei Mo
- Department of Microbiology, Queen Mary Hospital, Pokfulam, Hong Kong Special Administrative Region, China
| | - Jianli Cao
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
| | - Ronghui Liang
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
| | - Vincent Kwok-Man Poon
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
| | - Kong-Hung Sze
- State Key Laboratory of Emerging Infectious Diseases, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- Carol Yu Centre for Infection, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
| | - Jie Zhou
- State Key Laboratory of Emerging Infectious Diseases, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- Carol Yu Centre for Infection, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- Department of Clinical Microbiology and Infection Control, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Kelvin Kai-Wang To
- State Key Laboratory of Emerging Infectious Diseases, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- Carol Yu Centre for Infection, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- Department of Clinical Microbiology and Infection Control, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
- Department of Microbiology, Queen Mary Hospital, Pokfulam, Hong Kong Special Administrative Region, China
| | - Zhiwei Chen
- State Key Laboratory of Emerging Infectious Diseases, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- Carol Yu Centre for Infection, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- AIDS Institute, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China
| | - Honglin Chen
- State Key Laboratory of Emerging Infectious Diseases, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- Carol Yu Centre for Infection, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- Department of Clinical Microbiology and Infection Control, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
| | - Dong-Yan Jin
- School of Biomedical Sciences, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
| | - Jasper Fuk-Woo Chan
- State Key Laboratory of Emerging Infectious Diseases, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- Carol Yu Centre for Infection, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- Department of Clinical Microbiology and Infection Control, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
- Department of Microbiology, Queen Mary Hospital, Pokfulam, Hong Kong Special Administrative Region, China
- Hainan Medical University-The University of Hong Kong Joint Laboratory of Tropical Infectious Diseases, Hainan Medical University, Haikou, Hainan, China
| | - Kwok-Yung Yuen
- State Key Laboratory of Emerging Infectious Diseases, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- Carol Yu Centre for Infection, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China
- Department of Clinical Microbiology and Infection Control, The University of Hong Kong-Shenzhen Hospital, Shenzhen, China
- Department of Microbiology, Queen Mary Hospital, Pokfulam, Hong Kong Special Administrative Region, China
- Hainan Medical University-The University of Hong Kong Joint Laboratory of Tropical Infectious Diseases, Hainan Medical University, Haikou, Hainan, China
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48
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Mino RE, Chen Z, Mettlen M, Schmid SL. An internally eGFP-tagged α-adaptin is a fully functional and improved fiduciary marker for clathrin-coated pit dynamics. Traffic 2020; 21:603-616. [PMID: 32657003 PMCID: PMC7495412 DOI: 10.1111/tra.12755] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 07/05/2020] [Accepted: 07/06/2020] [Indexed: 12/18/2022]
Abstract
Clathrin mediated endocytosis (CME) has been extensively studied in living cells by quantitative total internal reflection fluorescence microscopy (TIRFM). Fluorescent protein fusions to subunits of the major coat proteins, clathrin light chains or the heterotetrameric adaptor protein (AP2) complexes, have been used as fiduciary markers of clathrin coated pits (CCPs). However, the functionality of these fusion proteins has not been rigorously compared. Here, we generated stable cells lines overexpressing mRuby‐CLCa and/or μ2‐eGFP, σ2‐eGFP, two markers currently in use, or a novel marker generated by inserting eGFP into the unstructured hinge region of the α subunit (α‐eGFP). Using biochemical and TIRFM‐based assays, we compared the functionality of the AP2 markers. All of the eGFP‐tagged subunits were efficiently incorporated into AP2 and displayed greater accuracy in image‐based CCP analyses than mRuby‐CLCa. However, overexpression of either μ2‐eGFP or σ2‐eGFP impaired transferrin receptor uptake. In addition, μ2‐eGFP reduced the rates of CCP initiation and σ2‐eGFP perturbed AP2 incorporation into CCPs and CCP maturation. In contrast, CME and CCP dynamics were unperturbed in cells overexpressing α‐eGFP. Moreover, α‐eGFP was a more sensitive and accurate marker of CCP dynamics than mRuby‐CLCa. Thus, our work establishes α‐eGFP as a robust, fully functional marker for CME.
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Affiliation(s)
- Rosa E Mino
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Zhiming Chen
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Marcel Mettlen
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Sandra L Schmid
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, Texas, USA
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49
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Kovtun O, Dickson VK, Kelly BT, Owen DJ, Briggs JAG. Architecture of the AP2/clathrin coat on the membranes of clathrin-coated vesicles. SCIENCE ADVANCES 2020; 6:eaba8381. [PMID: 32743075 PMCID: PMC7375805 DOI: 10.1126/sciadv.aba8381] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 04/17/2020] [Indexed: 05/19/2023]
Abstract
Clathrin-mediated endocytosis (CME) is crucial for modulating the protein composition of a cell's plasma membrane. Clathrin forms a cage-like, polyhedral outer scaffold around a vesicle, to which cargo-selecting clathrin adaptors are attached. Adaptor protein complex (AP2) is the key adaptor in CME. Crystallography has shown AP2 to adopt a range of conformations. Here, we used cryo-electron microscopy, tomography, and subtomogram averaging to determine structures, interactions, and arrangements of clathrin and AP2 at the key steps of coat assembly, from AP2 in solution to membrane-assembled clathrin-coated vesicles (CCVs). AP2 binds cargo and PtdIns(4,5)P 2 (phosphatidylinositol 4,5-bisphosphate)-containing membranes via multiple interfaces, undergoing conformational rearrangement from its cytosolic state. The binding mode of AP2 β2 appendage into the clathrin lattice in CCVs and buds implies how the adaptor structurally modulates coat curvature and coat disassembly.
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Affiliation(s)
- Oleksiy Kovtun
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge CB2 0QH, UK
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, 69117 Heidelberg , Germany
| | - Veronica Kane Dickson
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK
| | - Bernard T. Kelly
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK
- Corresponding author. (B.T.K.); (D.J.O.); (J.A.G.B.)
| | - David J. Owen
- Cambridge Institute for Medical Research, University of Cambridge, Hills Road, Cambridge CB2 0XY, UK
- Corresponding author. (B.T.K.); (D.J.O.); (J.A.G.B.)
| | - John A. G. Briggs
- MRC Laboratory of Molecular Biology, Cambridge Biomedical Campus, Cambridge CB2 0QH, UK
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, 69117 Heidelberg , Germany
- Corresponding author. (B.T.K.); (D.J.O.); (J.A.G.B.)
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50
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Paraan M, Mendez J, Sharum S, Kurtin D, He H, Stagg SM. The structures of natively assembled clathrin-coated vesicles. SCIENCE ADVANCES 2020; 6:eaba8397. [PMID: 32743076 PMCID: PMC7375819 DOI: 10.1126/sciadv.aba8397] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 06/05/2020] [Indexed: 05/19/2023]
Abstract
Clathrin-coated vesicles mediate trafficking of proteins and nutrients in the cell and between organelles. Proteins included in the clathrin-coated vesicles (CCVs) category include clathrin heavy chain (CHC), clathrin light chain (CLC), and a variety of adaptor protein complexes. Much is known about the structures of the individual CCV components, but data are lacking about the structures of the fully assembled complexes together with membrane and in complex with cargo. Here, we determined the structures of natively assembled CCVs in a variety of geometries. We show that the adaptor β2 appendages crosslink adjacent CHC β-propellers and that the appendage densities are enriched in CCV hexagonal faces. We resolve how adaptor protein 2 and other associated factors in hexagonal faces form an assembly hub with an extensive web of interactions between neighboring β-propellers and propose a structural model that explains how adaptor binding can direct the formation of pentagonal and hexagonal faces.
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Affiliation(s)
- Mohammadreza Paraan
- Institute of Molecular Biophysics, Florida State University, 91 Chieftan Way, Tallahassee, FL 32306, USA
| | - Joshua Mendez
- Department of Physics, Florida State University, 77 Chieftan Way, Tallahassee, FL 32306, USA
| | - Savanna Sharum
- Institute of Molecular Biophysics, Florida State University, 91 Chieftan Way, Tallahassee, FL 32306, USA
| | - Danielle Kurtin
- Institute of Molecular Biophysics, Florida State University, 91 Chieftan Way, Tallahassee, FL 32306, USA
| | - Huan He
- Institute of Molecular Biophysics, Florida State University, 91 Chieftan Way, Tallahassee, FL 32306, USA
| | - Scott M. Stagg
- Institute of Molecular Biophysics, Florida State University, 91 Chieftan Way, Tallahassee, FL 32306, USA
- Department of Chemistry and Biochemistry, Florida State University, 95 Chieftain Way, Tallahassee, FL 32306, USA
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