1
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Greig J, Bates GT, Yin DI, Briant K, Simonetti B, Cullen PJ, Brodsky FM. CHC22 clathrin recruitment to the early secretory pathway requires two-site interaction with SNX5 and p115. EMBO J 2024:10.1038/s44318-024-00198-y. [PMID: 39160272 DOI: 10.1038/s44318-024-00198-y] [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: 10/04/2023] [Revised: 07/15/2024] [Accepted: 07/17/2024] [Indexed: 08/21/2024] Open
Abstract
The two clathrin isoforms, CHC17 and CHC22, mediate separate intracellular transport routes. CHC17 performs endocytosis and housekeeping membrane traffic in all cells. CHC22, expressed most highly in skeletal muscle, shuttles the glucose transporter GLUT4 from the ERGIC (endoplasmic-reticulum-to-Golgi intermediate compartment) directly to an intracellular GLUT4 storage compartment (GSC), from where GLUT4 can be mobilized to the plasma membrane by insulin. Here, molecular determinants distinguishing CHC22 from CHC17 trafficking are defined. We show that the C-terminal trimerization domain of CHC22 interacts with SNX5, which also binds the ERGIC tether p115. SNX5, and the functionally redundant SNX6, are required for CHC22 localization independently of their participation in the endosomal ESCPE-1 complex. In tandem, an isoform-specific patch in the CHC22 N-terminal domain separately mediates binding to p115. This dual mode of clathrin recruitment, involving interactions at both N- and C-termini of the heavy chain, is required for CHC22 targeting to ERGIC membranes to mediate the Golgi-bypass route for GLUT4 trafficking. Interference with either interaction inhibits GLUT4 targeting to the GSC, defining a bipartite mechanism regulating a key pathway in human glucose metabolism.
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Affiliation(s)
- Joshua Greig
- Structural and Molecular Biology, Division of Biosciences, University College London, London, WC1E 6BT, UK
- Institute of Structural and Molecular Biology, Birkbeck and University College London, London, WC1E 7HX, UK
| | - George T Bates
- Structural and Molecular Biology, Division of Biosciences, University College London, London, WC1E 6BT, UK
- Institute of Structural and Molecular Biology, Birkbeck and University College London, London, WC1E 7HX, UK
| | - Daowen I Yin
- Structural and Molecular Biology, Division of Biosciences, University College London, London, WC1E 6BT, UK
- Institute of Structural and Molecular Biology, Birkbeck and University College London, London, WC1E 7HX, UK
| | - Kit Briant
- Structural and Molecular Biology, Division of Biosciences, University College London, London, WC1E 6BT, UK
- Institute of Structural and Molecular Biology, Birkbeck and University College London, London, WC1E 7HX, UK
| | - Boris Simonetti
- School of Biochemistry, Faculty of Life Sciences, University of Bristol, Bristol, UK
| | - Peter J Cullen
- School of Biochemistry, Faculty of Life Sciences, University of Bristol, Bristol, UK
| | - Frances M Brodsky
- Structural and Molecular Biology, Division of Biosciences, University College London, London, WC1E 6BT, UK.
- Institute of Structural and Molecular Biology, Birkbeck and University College London, London, WC1E 7HX, UK.
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2
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Szewczyk-Roszczenko OK, Roszczenko P, Shmakova A, Finiuk N, Holota S, Lesyk R, Bielawska A, Vassetzky Y, Bielawski K. The Chemical Inhibitors of Endocytosis: From Mechanisms to Potential Clinical Applications. Cells 2023; 12:2312. [PMID: 37759535 PMCID: PMC10527932 DOI: 10.3390/cells12182312] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Accepted: 09/07/2023] [Indexed: 09/29/2023] Open
Abstract
Endocytosis is one of the major ways cells communicate with their environment. This process is frequently hijacked by pathogens. Endocytosis also participates in the oncogenic transformation. Here, we review the approaches to inhibit endocytosis, discuss chemical inhibitors of this process, and discuss potential clinical applications of the endocytosis inhibitors.
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Affiliation(s)
| | - Piotr Roszczenko
- Department of Biotechnology, Medical University of Bialystok, Kilinskiego 1, 15-089 Bialystok, Poland; (P.R.); (A.B.)
| | - Anna Shmakova
- CNRS, UMR 9018, Institut Gustave Roussy, Université Paris-Saclay, 94800 Villejuif, France;
| | - Nataliya Finiuk
- Department of Regulation of Cell Proliferation and Apoptosis, Institute of Cell Biology of National Academy of Sciences of Ukraine, Drahomanov 14/16, 79005 Lviv, Ukraine;
| | - Serhii Holota
- Department of Pharmaceutical, Organic and Bioorganic Chemistry, Danylo Halytsky Lviv National Medical University, Pekarska 69, 79010 Lviv, Ukraine; (S.H.); (R.L.)
| | - Roman Lesyk
- Department of Pharmaceutical, Organic and Bioorganic Chemistry, Danylo Halytsky Lviv National Medical University, Pekarska 69, 79010 Lviv, Ukraine; (S.H.); (R.L.)
| | - Anna Bielawska
- Department of Biotechnology, Medical University of Bialystok, Kilinskiego 1, 15-089 Bialystok, Poland; (P.R.); (A.B.)
| | - Yegor Vassetzky
- CNRS, UMR 9018, Institut Gustave Roussy, Université Paris-Saclay, 94800 Villejuif, France;
| | - Krzysztof Bielawski
- Department of Synthesis and Technology of Drugs, Medical University of Bialystok, Kilinskiego 1, 15-089 Bialystok, Poland;
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3
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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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4
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Placidi G, Mattu C, Ciardelli G, Campa CC. Small molecules targeting endocytic uptake and recycling pathways. Front Cell Dev Biol 2023; 11:1125801. [PMID: 36968200 PMCID: PMC10036367 DOI: 10.3389/fcell.2023.1125801] [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: 12/16/2022] [Accepted: 02/23/2023] [Indexed: 03/12/2023] Open
Abstract
Over the past years a growing number of studies highlighted the pivotal role of intracellular trafficking in cell physiology. Among the distinct transport itineraries connecting the endocytic system, both internalization (endocytosis) and recycling (endocytic recycling) pathways were found fundamental to ensure cellular sensing, cell-to-cell communication, cellular division, and collective cell migration in tissue specific-contexts. Consistently, the dysregulation of endocytic trafficking pathways is correlated with several human diseases including both cancers and neurodegeneration. Aimed at suppress specific intracellular trafficking routes involved in disease onset and progression, huge efforts have been made to identify small molecule inhibitors with suitable pharmacological properties for in vivo administration. Here, we review most used drugs and recently discovered small molecules able to block endocytosis and endocytic recycling pathways. We characterize such pharmacological inhibitors by emphasizing their target specificity, molecular affinity, biological activity and efficacy in both in vitro and in vivo experimental models.
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Affiliation(s)
- Giampaolo Placidi
- Italian Institute for Genomic Medicine, Candiolo, Italy
- Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Turin, Italy
| | - Clara Mattu
- Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Turin, Italy
| | - Gianluca Ciardelli
- Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Turin, Italy
- Chemical-Physical Processes, National Research Council (CNR-IPCF), Pisa, Italy
| | - Carlo C. Campa
- Italian Institute for Genomic Medicine, Candiolo, Italy
- Candiolo Cancer Institute, FPO-IRCCS, Candiolo, Italy
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5
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Duan D, Hanson M, Holland DO, Johnson ME. Integrating protein copy numbers with interaction networks to quantify stoichiometry in clathrin-mediated endocytosis. Sci Rep 2022; 12:5413. [PMID: 35354856 PMCID: PMC8967901 DOI: 10.1038/s41598-022-09259-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 03/21/2022] [Indexed: 11/25/2022] Open
Abstract
Proteins that drive processes like clathrin-mediated endocytosis (CME) are expressed at copy numbers within a cell and across cell types varying from hundreds (e.g. auxilin) to millions (e.g. clathrin). These variations contain important information about function, but without integration with the interaction network, they cannot capture how supply and demand for each protein depends on binding to shared and distinct partners. Here we construct the interface-resolved network of 82 proteins involved in CME and establish a metric, a stoichiometric balance ratio (SBR), that quantifies whether each protein in the network has an abundance that is sub- or super-stoichiometric dependent on the global competition for binding. We find that highly abundant proteins (like clathrin) are super-stoichiometric, but that not all super-stoichiometric proteins are highly abundant, across three cell populations (HeLa, fibroblast, and neuronal synaptosomes). Most strikingly, within all cells there is significant competition to bind shared sites on clathrin and the central AP-2 adaptor by other adaptor proteins, resulting in most being in excess supply. Our network and systematic analysis, including response to perturbations of network components, show how competition for shared binding sites results in functionally similar proteins having widely varying stoichiometries, due to variations in both abundance and their unique network of binding partners.
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Affiliation(s)
- Daisy Duan
- TC Jenkins Department of Biophysics, Johns Hopkins University, 3400 N Charles St, Baltimore, MD, 21218, USA
| | - Meretta Hanson
- TC Jenkins Department of Biophysics, Johns Hopkins University, 3400 N Charles St, Baltimore, MD, 21218, USA
| | | | - Margaret E Johnson
- TC Jenkins Department of Biophysics, Johns Hopkins University, 3400 N Charles St, Baltimore, MD, 21218, USA.
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6
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Prichard KL, O'Brien NS, Murcia SR, Baker JR, McCluskey A. Role of Clathrin and Dynamin in Clathrin Mediated Endocytosis/Synaptic Vesicle Recycling and Implications in Neurological Diseases. Front Cell Neurosci 2022; 15:754110. [PMID: 35115907 PMCID: PMC8805674 DOI: 10.3389/fncel.2021.754110] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 12/10/2021] [Indexed: 12/17/2022] Open
Abstract
Endocytosis is a process essential to the health and well-being of cell. It is required for the internalisation and sorting of “cargo”—the macromolecules, proteins, receptors and lipids of cell signalling. Clathrin mediated endocytosis (CME) is one of the key processes required for cellular well-being and signalling pathway activation. CME is key role to the recycling of synaptic vesicles [synaptic vesicle recycling (SVR)] in the brain, it is pivotal to signalling across synapses enabling intracellular communication in the sensory and nervous systems. In this review we provide an overview of the general process of CME with a particular focus on two key proteins: clathrin and dynamin that have a central role to play in ensuing successful completion of CME. We examine these two proteins as they are the two endocytotic proteins for which small molecule inhibitors, often of known mechanism of action, have been identified. Inhibition of CME offers the potential to develop therapeutic interventions into conditions involving defects in CME. This review will discuss the roles and the current scope of inhibitors of clathrin and dynamin, providing an insight into how further developments could affect neurological disease treatments.
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7
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Acconcia F, Fiocchetti M, Busonero C, Fernandez VS, Montalesi E, Cipolletti M, Pallottini V, Marino M. The extra-nuclear interactome of the estrogen receptors: implications for physiological functions. Mol Cell Endocrinol 2021; 538:111452. [PMID: 34500041 DOI: 10.1016/j.mce.2021.111452] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 08/19/2021] [Accepted: 09/02/2021] [Indexed: 02/07/2023]
Abstract
Over the last decades, a great body of evidence has defined a novel view of the cellular mechanism of action of the steroid hormone 17β-estradiol (E2) through its estrogen receptors (i.e., ERα and ERβ). It is now clear that the E2-activated ERs work both as transcription factors and extra-nuclear plasma membrane-localized receptors. The activation of a plethora of signal transduction cascades follows the E2-dependent engagement of plasma membrane-localized ERs and is required for the coordination of gene expression, which ultimately controls the occurrence of the pleiotropic effects of E2. The definition of the molecular mechanisms by which the ERs locate at the cell surface (i.e., palmitoylation and protein association) determined the quest for understanding the specificity of the extra-nuclear E2 signaling. The use of mice models lacking the plasma membrane ERα localization unveiled that the extra-nuclear E2 signaling is operational in vivo but tissue-specific. However, the underlying molecular details for such ERs signaling diversity in the perspective of the E2 physiological functions in the different cellular contexts are still not understood. Therefore, to gain insights into the tissue specificity of the extra-nuclear E2 signaling to physiological functions, here we reviewed the known ERs extra-nuclear interactors and tried to extrapolate from available databases the ERα and ERβ extra-nuclear interactomes. Based on literature data, it is possible to conclude that by specifically binding to extra-nuclear localized proteins in different sub-cellular compartments, the ERs fine-tune their molecular activities. Moreover, we report that the context-dependent diversity of the ERs-mediated extra-nuclear E2 actions can be ascribed to the great flexibility of the physical structures of ERs and the spatial-temporal organization of the logistics of the cells (i.e., the endocytic compartments). Finally, we provide lists of proteins belonging to the potential ERα and ERβ extra-nuclear interactomes and propose that the systematic experimental definition of the ERs extra-nuclear interactomes in different tissues represents the next step for the research in the ERs field. Such characterization will be fundamental for the identification of novel druggable targets for the innovative treatment of ERs-related diseases.
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Affiliation(s)
- Filippo Acconcia
- Department of Sciences, Section Biomedical Sciences, and Technology, University Roma Tre, Viale Guglielmo Marconi, 446, I-00146, Rome, Italy.
| | - Marco Fiocchetti
- Department of Sciences, Section Biomedical Sciences, and Technology, University Roma Tre, Viale Guglielmo Marconi, 446, I-00146, Rome, Italy
| | - Claudia Busonero
- Department of Sciences, Section Biomedical Sciences, and Technology, University Roma Tre, Viale Guglielmo Marconi, 446, I-00146, Rome, Italy
| | - Virginia Solar Fernandez
- Department of Sciences, Section Biomedical Sciences, and Technology, University Roma Tre, Viale Guglielmo Marconi, 446, I-00146, Rome, Italy
| | - Emiliano Montalesi
- Department of Sciences, Section Biomedical Sciences, and Technology, University Roma Tre, Viale Guglielmo Marconi, 446, I-00146, Rome, Italy
| | - Manuela Cipolletti
- Department of Sciences, Section Biomedical Sciences, and Technology, University Roma Tre, Viale Guglielmo Marconi, 446, I-00146, Rome, Italy
| | - Valentina Pallottini
- Department of Sciences, Section Biomedical Sciences, and Technology, University Roma Tre, Viale Guglielmo Marconi, 446, I-00146, Rome, Italy
| | - Maria Marino
- Department of Sciences, Section Biomedical Sciences, and Technology, University Roma Tre, Viale Guglielmo Marconi, 446, I-00146, Rome, Italy.
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8
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Shimizu Y, Takagi J, Ito E, Ito Y, Ebine K, Komatsu Y, Goto Y, Sato M, Toyooka K, Ueda T, Kurokawa K, Uemura T, Nakano A. Cargo sorting zones in the trans-Golgi network visualized by super-resolution confocal live imaging microscopy in plants. Nat Commun 2021; 12:1901. [PMID: 33772008 PMCID: PMC7997971 DOI: 10.1038/s41467-021-22267-0] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 03/06/2021] [Indexed: 02/01/2023] Open
Abstract
The trans-Golgi network (TGN) has been known as a key platform to sort and transport proteins to their final destinations in post-Golgi membrane trafficking. However, how the TGN sorts proteins with different destinies still remains elusive. Here, we examined 3D localization and 4D dynamics of TGN-localized proteins of Arabidopsis thaliana that are involved in either secretory or vacuolar trafficking from the TGN, by a multicolor high-speed and high-resolution spinning-disk confocal microscopy approach that we developed. We demonstrate that TGN-localized proteins exhibit spatially and temporally distinct distribution. VAMP721 (R-SNARE), AP (adaptor protein complex)-1, and clathrin which are involved in secretory trafficking compose an exclusive subregion, whereas VAMP727 (R-SNARE) and AP-4 involved in vacuolar trafficking compose another subregion on the same TGN. Based on these findings, we propose that the single TGN has at least two subregions, or "zones", responsible for distinct cargo sorting: the secretory-trafficking zone and the vacuolar-trafficking zone.
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Affiliation(s)
- Yutaro Shimizu
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced Photonics, Wako, Saitama, Japan ,grid.26999.3d0000 0001 2151 536XDepartment of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo Japan
| | - Junpei Takagi
- grid.258669.60000 0000 8565 5938Faculty of Science and Engineering, Konan University, Kobe, Hyogo, Japan
| | - Emi Ito
- grid.412314.10000 0001 2192 178XGraduate School of Humanities and Sciences, Ochanomizu University, Bunkyo-ku, Tokyo Japan
| | - Yoko Ito
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced Photonics, Wako, Saitama, Japan ,grid.4444.00000 0001 2112 9282Laboratoire de Biogenèse Membranaire, UMR 5200, CNRS, Université de Bordeaux, Villenave d’Ornon, France
| | - Kazuo Ebine
- grid.419396.00000 0004 0618 8593Division of Cellular Dynamics, National Institute for Basic Biology, Okazaki, Aichi Japan ,grid.275033.00000 0004 1763 208XThe Department of Basic Biology, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi Japan
| | - Yamato Komatsu
- grid.26999.3d0000 0001 2151 536XDepartment of Biological Sciences, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo Japan
| | - Yumi Goto
- grid.7597.c0000000094465255Technology Platform Division, Mass Spectrometry and Microscopy Unit, RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa Japan
| | - Mayuko Sato
- grid.7597.c0000000094465255Technology Platform Division, Mass Spectrometry and Microscopy Unit, RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa Japan
| | - Kiminori Toyooka
- grid.7597.c0000000094465255Technology Platform Division, Mass Spectrometry and Microscopy Unit, RIKEN Center for Sustainable Resource Science, Yokohama, Kanagawa Japan
| | - Takashi Ueda
- grid.419396.00000 0004 0618 8593Division of Cellular Dynamics, National Institute for Basic Biology, Okazaki, Aichi Japan ,grid.275033.00000 0004 1763 208XThe Department of Basic Biology, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi Japan
| | - Kazuo Kurokawa
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced Photonics, Wako, Saitama, Japan
| | - Tomohiro Uemura
- grid.412314.10000 0001 2192 178XGraduate School of Humanities and Sciences, Ochanomizu University, Bunkyo-ku, Tokyo Japan
| | - Akihiko Nakano
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced Photonics, Wako, Saitama, Japan
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9
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Chen Z, Mino RE, Mettlen M, Michaely P, Bhave M, Reed DK, Schmid SL. Wbox2: A clathrin terminal domain-derived peptide inhibitor of clathrin-mediated endocytosis. J Cell Biol 2021; 219:151850. [PMID: 32520988 PMCID: PMC7480105 DOI: 10.1083/jcb.201908189] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 12/03/2019] [Accepted: 05/14/2020] [Indexed: 12/11/2022] Open
Abstract
Clathrin-mediated endocytosis (CME) occurs via the formation of clathrin-coated vesicles from clathrin-coated pits (CCPs). Clathrin is recruited to CCPs through interactions between the AP2 complex and its N-terminal domain, which in turn recruits endocytic accessory proteins. Inhibitors of CME that interfere with clathrin function have been described, but their specificity and mechanisms of action are unclear. Here we show that overexpression of the N-terminal domain with (TDD) or without (TD) the distal leg inhibits CME and CCP dynamics by perturbing clathrin interactions with AP2 and SNX9. TDD overexpression does not affect clathrin-independent endocytosis or, surprisingly, AP1-dependent lysosomal trafficking from the Golgi. We designed small membrane–permeant peptides that encode key functional residues within the four known binding sites on the TD. One peptide, Wbox2, encoding residues along the W-box motif binding surface, binds to SNX9 and AP2 and potently and acutely inhibits CME.
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Affiliation(s)
- Zhiming Chen
- Department of Cell Biology, University of Texas Southwestern Medical Center, TX
| | - Rosa E Mino
- Department of Cell Biology, University of Texas Southwestern Medical Center, TX
| | - Marcel Mettlen
- Department of Cell Biology, University of Texas Southwestern Medical Center, TX
| | - Peter Michaely
- Department of Cell Biology, University of Texas Southwestern Medical Center, TX
| | - Madhura Bhave
- Department of Cell Biology, University of Texas Southwestern Medical Center, TX
| | - Dana Kim Reed
- Department of Cell Biology, University of Texas Southwestern Medical Center, TX
| | - Sandra L Schmid
- Department of Cell Biology, University of Texas Southwestern Medical Center, TX
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10
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Bayati A, Kumar R, Francis V, McPherson PS. SARS-CoV-2 infects cells after viral entry via clathrin-mediated endocytosis. J Biol Chem 2021; 296:100306. [PMID: 33476648 PMCID: PMC7816624 DOI: 10.1016/j.jbc.2021.100306] [Citation(s) in RCA: 291] [Impact Index Per Article: 97.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 01/06/2021] [Accepted: 01/15/2021] [Indexed: 12/19/2022] Open
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of COVID-19, so understanding its biology and infection mechanisms is critical to facing this major medical challenge. SARS-CoV-2 is known to use its spike glycoprotein to interact with the cell surface as a first step in the infection process. As for other coronaviruses, it is likely that SARS-CoV-2 next undergoes endocytosis, but whether or not this is required for infectivity and the precise endocytic mechanism used are unknown. Using purified spike glycoprotein and lentivirus pseudotyped with spike glycoprotein, a common model of SARS-CoV-2 infectivity, we now demonstrate that after engagement with the plasma membrane, SARS-CoV-2 undergoes rapid, clathrin-mediated endocytosis. This suggests that transfer of viral RNA to the cell cytosol occurs from the lumen of the endosomal system. Importantly, we further demonstrate that knockdown of clathrin heavy chain, which blocks clathrin-mediated endocytosis, reduces viral infectivity. These discoveries reveal that SARS-CoV-2 uses clathrin-mediated endocytosis to gain access into cells and suggests that this process is a key aspect of virus infectivity.
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Affiliation(s)
- Armin Bayati
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Rahul Kumar
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Vincent Francis
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
| | - Peter S McPherson
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada.
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11
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Tolsma TO, Febvre HP, Olson DM, Di Pietro SM. Cargo-mediated recruitment of the endocytic adaptor protein Sla1 in S. cerevisiae. J Cell Sci 2020; 133:jcs247684. [PMID: 32907853 PMCID: PMC7578355 DOI: 10.1242/jcs.247684] [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: 04/17/2020] [Accepted: 08/27/2020] [Indexed: 11/20/2022] Open
Abstract
Endocytosis of plasma membrane proteins is mediated by their interaction with adaptor proteins. Conversely, emerging evidence suggests that adaptor protein recruitment to the plasma membrane may depend on binding to endocytic cargo. To test this idea, we analyzed the yeast adaptor protein Sla1, which binds membrane proteins harboring the endocytic signal NPFxD via the Sla1 SHD1 domain. Consistently, SHD1 domain point mutations that disrupted NPFxD binding caused a proportional reduction in Sla1-GFP recruitment to endocytic sites. Furthermore, simultaneous SHD1 domain point mutation and deletion of the C-terminal LxxQxTG repeat (SR) region linking Sla1 to coat proteins Pan1 and End3 resulted in total loss of Sla1-GFP recruitment to the plasma membrane. These data suggest that multiple interactions are needed for recruitment of Sla1 to the membrane. Interestingly, a Sla1 fragment containing just the third SH3 domain, which binds ubiquitin, and the SHD1 domain displayed broad surface localization, suggesting plasma membrane recruitment is mediated by interaction with both NPFxD-containing and ubiquitylated plasma membrane proteins. Our results also imply that a Sla1 NPF motif adjacent to the SR region might regulate the Sla1-cargo interaction, mechanistically linking Sla1 cargo binding to endocytic site recruitment.
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Affiliation(s)
- Thomas O Tolsma
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523-1870, USA
| | - Hallie P Febvre
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523-1870, USA
| | - Deanna M Olson
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523-1870, USA
| | - Santiago M Di Pietro
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523-1870, USA
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12
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Rondelet A, Lin YC, Singh D, Porfetye AT, Thakur HC, Hecker A, Brinkert P, Schmidt N, Bendre S, Müller F, Mazul L, Widlund PO, Bange T, Hiller M, Vetter IR, Bird AW. Clathrin's adaptor interaction sites are repurposed to stabilize microtubules during mitosis. J Cell Biol 2020; 219:133599. [PMID: 31932847 PMCID: PMC7041688 DOI: 10.1083/jcb.201907083] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 10/31/2019] [Accepted: 11/24/2019] [Indexed: 11/22/2022] Open
Abstract
Clathrin ensures mitotic spindle stability and efficient chromosome alignment, independently of its vesicle trafficking function. Although clathrin localizes to the mitotic spindle and kinetochore fiber microtubule bundles, the mechanisms by which clathrin stabilizes microtubules are unclear. We show that clathrin adaptor interaction sites on clathrin heavy chain (CHC) are repurposed during mitosis to directly recruit the microtubule-stabilizing protein GTSE1 to the spindle. Structural analyses reveal that these sites interact directly with clathrin-box motifs on GTSE1. Disruption of this interaction releases GTSE1 from spindles, causing defects in chromosome alignment. Surprisingly, this disruption destabilizes astral microtubules, but not kinetochore-microtubule attachments, and chromosome alignment defects are due to a failure of chromosome congression independent of kinetochore-microtubule attachment stability. GTSE1 recruited to the spindle by clathrin stabilizes microtubules by inhibiting the microtubule depolymerase MCAK. This work uncovers a novel role of clathrin adaptor-type interactions to stabilize nonkinetochore fiber microtubules to support chromosome congression, defining for the first time a repurposing of this endocytic interaction mechanism during mitosis.
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Affiliation(s)
- Arnaud Rondelet
- Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Yu-Chih Lin
- Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Divya Singh
- Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | | | - Harish C Thakur
- Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Andreas Hecker
- Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Pia Brinkert
- Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Nadine Schmidt
- Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Shweta Bendre
- Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | | | - Lisa Mazul
- Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Per O Widlund
- Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
| | - Tanja Bange
- Max Planck Institute of Molecular Physiology, Dortmund, Germany
| | - Michael Hiller
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany.,Max Planck Institute for the Physics of Complex Systems, Dresden, Germany.,Center for Systems Biology, Dresden, Germany
| | - Ingrid R Vetter
- Max Planck Institute of Molecular Physiology, Dortmund, Germany
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13
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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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14
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Dunn VK, Gleason E. Inhibition of endocytosis suppresses the nitric oxide-dependent release of Cl- in retinal amacrine cells. PLoS One 2018; 13:e0201184. [PMID: 30044876 PMCID: PMC6059450 DOI: 10.1371/journal.pone.0201184] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 07/10/2018] [Indexed: 11/18/2022] Open
Abstract
Our lab has previously shown that nitric oxide (NO) can alter the synaptic response properties of amacrine cells by releasing Cl- from internal acidic compartments. This alteration in the Cl- gradient brings about a positive shift in the reversal potential of the GABA-gated current, which can convert inhibitory synapses into excitatory synapses. Recently, we have shown that the cystic fibrosis transmembrane regulator (CFTR) Cl- channel is involved in the Cl- release. Here, we test the hypothesis that (acidic) synaptic vesicles are a source of NO-releasable Cl- in chick retinal amacrine cells. If SVs are a source of Cl-, then depleting synaptic vesicles should decrease the nitric oxide-dependent shift in the reversal potential of the GABA-gated current. The efficacy of four inhibitors of dynamin (dynasore, Dyngo 4a, Dynole 34-2, and MiTMAB) were evaluated. In order to deplete synaptic vesicles, voltage-steps were used to activate V-gated Ca2+ channels and stimulate the synaptic vesicle cycle either under control conditions or after treatment with the dynamin inhibitors. Voltage-ramps were used to measure the NO-dependent shift in the reversal potential of the GABA-gated currents under both conditions. Our results reveal that activating the synaptic vesicle cycle in the presence of dynasore or Dyngo 4a blocked the NO-dependent shift in EGABA. However, we also discovered that some dynamin inhibitors reduced Ca2+ signaling and L-type Ca2+ currents. Conversely, dynasore also increased neurotransmitter release at autaptic sites. To further resolve the mechanism underlying the inhibition of the NO-dependent shift in the reversal potential for the GABA-gated currents, we also tested the effects of the clathrin assembly inhibitor Pitstop 2 and found that this compound also inhibited the shift. These data provide evidence that dynamin inhibitors have multiple effects on amacrine cell synaptic transmission. These data also suggest that inhibition of endocytosis disrupts the ability of NO to elicit Cl- release from internal stores which may in part be due to depletion of synaptic vesicles.
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Affiliation(s)
- Vernon K. Dunn
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, United States of America
| | - Evanna Gleason
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana, United States of America
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15
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Tolsma TO, Cuevas LM, Di Pietro SM. The Sla1 adaptor-clathrin interaction regulates coat formation and progression of endocytosis. Traffic 2018. [PMID: 29542219 DOI: 10.1111/tra.12563] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Clathrin-mediated endocytosis is a fundamental transport pathway that depends on numerous protein-protein interactions. Testing the importance of the adaptor protein-clathrin interaction for coat formation and progression of endocytosis in vivo has been difficult due to experimental constrains. Here, we addressed this question using the yeast clathrin adaptor Sla1, which is unique in showing a cargo endocytosis defect upon substitution of 3 amino acids in its clathrin-binding motif (sla1AAA ) that disrupt clathrin binding. Live-cell imaging showed an impaired Sla1-clathrin interaction causes reduced clathrin levels but increased Sla1 levels at endocytic sites. Moreover, the rate of Sla1 recruitment was reduced indicating proper dynamics of both clathrin and Sla1 depend on their interaction. sla1AAA cells showed a delay in progression through the various stages of endocytosis. The Arp2/3-dependent actin polymerization machinery was present for significantly longer time before actin polymerization ensued, revealing a link between coat formation and activation of actin polymerization. Ultimately, in sla1AAA cells a larger than normal actin network was formed, dramatically higher levels of various machinery proteins other than clathrin were recruited, and the membrane profile of endocytic invaginations was longer. Thus, the Sla1-clathrin interaction is important for coat formation, regulation of endocytic progression and membrane bending.
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Affiliation(s)
- Thomas O Tolsma
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado
| | - Lena M Cuevas
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado
| | - Santiago M Di Pietro
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, Colorado
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16
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Sorkina T, Ma S, Larsen MB, Watkins SC, Sorkin A. Small molecule induced oligomerization, clustering and clathrin-independent endocytosis of the dopamine transporter. eLife 2018; 7:32293. [PMID: 29630493 PMCID: PMC5896956 DOI: 10.7554/elife.32293] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 03/22/2018] [Indexed: 12/14/2022] Open
Abstract
Clathrin-independent endocytosis (CIE) mediates internalization of many transmembrane proteins but the mechanisms of cargo recruitment during CIE are poorly understood. We found that the cell-permeable furopyrimidine AIM-100 promotes dramatic oligomerization, clustering and CIE of human and mouse dopamine transporters (DAT), but not of their close homologues, norepinephrine and serotonin transporters. All effects of AIM-100 on DAT and the occupancy of substrate binding sites in the transporter were mutually exclusive, suggesting that AIM-100 may act by binding to DAT. Surprisingly, AIM-100-induced DAT endocytosis was independent of dynamin, cholesterol-rich microdomains and actin cytoskeleton, implying that a novel endocytic mechanism is involved. AIM-100 stimulated trafficking of internalized DAT was also unusual: DAT accumulated in early endosomes without significant recycling or degradation. We propose that AIM-100 augments DAT oligomerization through an allosteric mechanism associated with the DAT conformational state, and that oligomerization-triggered clustering leads to a coat-independent endocytosis and subsequent endosomal retention of DAT.
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Affiliation(s)
- Tatiana Sorkina
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, United States
| | - Shiqi Ma
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, United States
| | - Mads Breum Larsen
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, United States
| | - Simon C Watkins
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, United States
| | - Alexander Sorkin
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, United States
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17
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Smith SM, Baker M, Halebian M, Smith CJ. Weak Molecular Interactions in Clathrin-Mediated Endocytosis. Front Mol Biosci 2017; 4:72. [PMID: 29184887 PMCID: PMC5694535 DOI: 10.3389/fmolb.2017.00072] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 10/11/2017] [Indexed: 11/21/2022] Open
Abstract
Clathrin-mediated endocytosis is a process by which specific molecules are internalized from the cell periphery for delivery to early endosomes. The key stages in this step-wise process, from the starting point of cargo recognition, to the later stage of assembly of the clathrin coat, are dependent on weak interactions between a large network of proteins. This review discusses the structural and functional data that have improved our knowledge and understanding of the main weak molecular interactions implicated in clathrin-mediated endocytosis, with a particular focus on the two key proteins: AP2 and clathrin.
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Affiliation(s)
- Sarah M Smith
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Michael Baker
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Mary Halebian
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Corinne J Smith
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
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18
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Gao W, Shi P, Chen X, Zhang L, Liu J, Fan X, Luo X. Clathrin-mediated integrin αIIbβ3 trafficking controls platelet spreading. Platelets 2017; 29:610-621. [PMID: 28961039 DOI: 10.1080/09537104.2017.1353682] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Dynamic endocytic and exocytic trafficking of integrins is an important mechanism for cell migration, invasion, and cytokinesis. Endocytosis of integrin can be classified as clathrin dependent and clathrin independent manners. And rapid delivery of endocytic integrins back to the plasma membrane is key intracellular signals and is indispensable for cell movement. Integrin αIIbβ3 plays a critical role in thrombosis and hemostasis. Although previous studies have demonstrated that internalization of fibrinogen-bound αIIbβ3 may regulate platelet activation, the roles of endocytic and exocytic trafficking of integrin αIIbβ3 in platelet activation are unclear. In this study, we found that a selective inhibitor of clathrin-mediated endocytosis pitstop 2 inhibited human platelet spreading on immobilized fibrinogen (Fg). Mechanism studies revealed that pitstop 2 did not block the endocytosis of αIIbβ3 and Fg uptake, but inhibit the recycling of αIIbβ3 to plasma membrane during platelet or CHO cells bearing αIIbβ3 spreading on immobilized Fg. And pitstop 2 enhanced the association of αIIbβ3 with clathrin, and AP2 indicated that pitstop 2 inhibit platelet activation is probably due to disturbance of the dynamic dissociation of αIIbβ3 from clathrin and AP2. Further study demonstrated that Src/PLC/PKC was the key pathway to trigger the endocytosis of αIIbβ3 during platelet activation. Pitstop 2 also inhibited platelet aggregation and secretion. Our findings suggest integrin αIIbβ3 trafficking is clathrin dependent and plays a critical role in platelet spreading, and pitstop 2 may serve as an effective tool to address clathrin-mediated trafficking in platelets.
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Affiliation(s)
- Wen Gao
- a Department of Cardiology , Huashan Hospital, Fudan University , Shanghai , China
| | - Panlai Shi
- b Department of Biochemistry and Molecular Cell Biology, Shanghai Key Laboratory of Tumor Microenvironment and Inflammation , Shanghai Jiao Tong University of Medscine , Shanghai , China
| | - Xue Chen
- b Department of Biochemistry and Molecular Cell Biology, Shanghai Key Laboratory of Tumor Microenvironment and Inflammation , Shanghai Jiao Tong University of Medscine , Shanghai , China
| | - Lin Zhang
- b Department of Biochemistry and Molecular Cell Biology, Shanghai Key Laboratory of Tumor Microenvironment and Inflammation , Shanghai Jiao Tong University of Medscine , Shanghai , China
| | - Junling Liu
- b Department of Biochemistry and Molecular Cell Biology, Shanghai Key Laboratory of Tumor Microenvironment and Inflammation , Shanghai Jiao Tong University of Medscine , Shanghai , China
| | - Xuemei Fan
- b Department of Biochemistry and Molecular Cell Biology, Shanghai Key Laboratory of Tumor Microenvironment and Inflammation , Shanghai Jiao Tong University of Medscine , Shanghai , China
| | - Xinping Luo
- a Department of Cardiology , Huashan Hospital, Fudan University , Shanghai , China
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19
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Functional implication of the common evolutionary origin of nuclear pore complex and endomembrane management systems. Semin Cell Dev Biol 2017; 68:10-17. [PMID: 28473267 DOI: 10.1016/j.semcdb.2017.04.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Accepted: 04/26/2017] [Indexed: 11/24/2022]
Abstract
Nuclear pore complexes (NPCs) are the sole gateway between the cytoplasm and the nucleus serving both as stringent permeability barrier and active transporters between the two compartments of eukaryotic cells. Complete mechanistic understanding of how these two functions are implemented within one and the same transport machine has not been attained to date. Based on several lines of structural evidence, a hypothesis was proposed postulating that NPCs shares common evolutionary origin with other intracellular systems responsible for active management of endomembranes. In this review we attempt to summarize the evidence supporting this hypothesis. The structural data obtained so far is evaluated and supplemented with the analysis of the functional evidence. Based on this analysis, a model is proposed which integrates the knowledge from the field of NPC function with that obtained from other endomembrane management systems in an attempt to shed new light on the mechanism of the NPC active transport.
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20
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Giani M, den Otter WK, Briels WJ. Early stages of clathrin aggregation at a membrane in coarse-grained simulations. J Chem Phys 2017; 146:155102. [DOI: 10.1063/1.4979985] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Affiliation(s)
- M. Giani
- Multi Scale Mechanics, Faculty of Engineering Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
- Computational BioPhysics, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
- MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - W. K. den Otter
- Multi Scale Mechanics, Faculty of Engineering Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
- Computational BioPhysics, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
- MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - W. J. Briels
- Computational BioPhysics, Faculty of Science and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
- MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
- Forschungszentrum Jülich, ICS 3, D-52425 Jülich, Germany
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21
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Martzoukou O, Amillis S, Zervakou A, Christoforidis S, Diallinas G. The AP-2 complex has a specialized clathrin-independent role in apical endocytosis and polar growth in fungi. eLife 2017; 6. [PMID: 28220754 PMCID: PMC5338921 DOI: 10.7554/elife.20083] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 02/07/2017] [Indexed: 12/26/2022] Open
Abstract
Filamentous fungi provide excellent systems for investigating the role of the AP-2 complex in polar growth. Using Aspergillus nidulans, we show that AP-2 has a clathrin-independent essential role in polarity maintenance and growth. This is in line with a sequence analysis showing that the AP-2 β subunit (β2) of higher fungi lacks a clathrin-binding domain, and experiments showing that AP-2 does not co-localize with clathrin. We provide genetic and cellular evidence that AP-2 interacts with endocytic markers SlaBEnd4 and SagAEnd3 and the lipid flippases DnfA and DnfB in the sub-apical collar region of hyphae. The role of AP-2 in the maintenance of proper apical membrane lipid and cell wall composition is further supported by its functional interaction with BasA (sphingolipid biosynthesis) and StoA (apical sterol-rich membrane domains), and its essentiality in polar deposition of chitin. Our findings support that the AP-2 complex of dikarya has acquired, in the course of evolution, a specialized clathrin-independent function necessary for fungal polar growth. DOI:http://dx.doi.org/10.7554/eLife.20083.001
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Affiliation(s)
- Olga Martzoukou
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - Sotiris Amillis
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - Amalia Zervakou
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - Savvas Christoforidis
- Institute of Molecular Biology and Biotechnology-Biomedical Research, Foundation for Research and Technology, Ioannina, Greece.,Laboratory of Biological Chemistry, Department of Medicine, School of Health Sciences, University of Ioannina, Ioannina, Greece
| | - George Diallinas
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
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22
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Hoepflinger MC, Hoeftberger M, Sommer A, Hametner C, Foissner I. Clathrin in Chara australis: Molecular Analysis and Involvement in Charasome Degradation and Constitutive Endocytosis. FRONTIERS IN PLANT SCIENCE 2017; 8:20. [PMID: 28184226 PMCID: PMC5266738 DOI: 10.3389/fpls.2017.00020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 01/04/2017] [Indexed: 05/31/2023]
Abstract
Charasomes are convoluted plasma membrane domains in characean green algae. They are known to form in response to light via secretion of trans-Golgi network (TGN) vesicles and local inhibition of endocytosis. Charasomes are involved in the acidification of their aqueous environment, thereby facilitating photosynthesis-dependent carbon uptake. Charasome formation is reversible to allow cells to adapt to different light conditions. Here, we show that darkness-induced degradation of charasomes involves the formation of coated pits and coated vesicles. The darkness-induced degradation of charasomes can be inhibited by 1-2 μM ikarugamycin (IKA), which is considered to be a specific inhibitor of clathrin-dependent endocytosis. At a much higher concentration (100 μM), IKA also significantly reduces the internalization of styryl dyes, indicating uptake via clathrin-coated vesicles (CV). We are the first to present evidence, based on fine structure investigation, that IKA does not interfere with the formation of clathrin coat, but inhibits the detachment and/or further processing of coated vesicles. Both charasome degradation and constitutive endocytosis are also significantly inhibited by sterol complexing agents (methyl-ß-cyclodextrin and filipin). The absence of an additive effect, when applied together with IKA, suggests that charasome degradation and constitutive endocytosis (measured via styryl dye uptake) is not inhibited due to membrane retrieval via lipid rafts, but due to clathrin coat formation requirement of a specific set of sterols. Analysis of Chara australis clathrin proteins revealed two heavy chains and several light chains with sequence peculiarities, suggesting functional and/or species specific differences. The data obtained indicate that clathrin plays a central role not only in constitutive endocytosis but also in the degradation of charasomes, thereby representing a valuable system for studying targeted exo- and endocytosis.
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23
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Muenzner J, Traub LM, Kelly BT, Graham SC. Cellular and viral peptides bind multiple sites on the N-terminal domain of clathrin. Traffic 2016; 18:44-57. [PMID: 27813245 PMCID: PMC5182127 DOI: 10.1111/tra.12457] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Revised: 10/31/2016] [Accepted: 10/31/2016] [Indexed: 12/17/2022]
Abstract
Short peptide motifs in unstructured regions of clathrin‐adaptor proteins recruit clathrin to membranes to facilitate post‐Golgi membrane transport. Three consensus clathrin‐binding peptide sequences have been identified and structural studies show that each binds distinct sites on the clathrin heavy chain N‐terminal domain (NTD). A fourth binding site for adaptors on NTD has been functionally identified but not structurally characterised. We have solved high resolution structures of NTD bound to peptide motifs from the cellular clathrin adaptors β2 adaptin and amphiphysin plus a putative viral clathrin adaptor, hepatitis D virus large antigen (HDAg‐L). Surprisingly, with each peptide we observe simultaneous peptide binding at multiple sites on NTD and viral peptides binding to the same sites as cellular peptides. Peptides containing clathrin‐box motifs (CBMs) with the consensus sequence LΦxΦ[DE] bind at the ‘arrestin box’ on NTD, between β‐propeller blades 4 and 5, which had previously been thought to bind a distinct consensus sequence. Further, we structurally define the fourth peptide binding site on NTD, which we term the Royle box. In vitro binding assays show that clathrin is more readily captured by cellular CBMs than by HDAg‐L, and site‐directed mutagenesis confirms that multiple binding sites on NTD contribute to efficient capture by CBM peptides.
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Affiliation(s)
- Julia Muenzner
- Department of Pathology, University of Cambridge, Cambridge, UK
| | - Linton M Traub
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Bernard T Kelly
- Cambridge Institute for Medical Research, Department of Clinical Biochemistry, University of Cambridge, Cambridge, UK
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24
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Windheim M. Interleukin-1-induced gene expression requires the membrane-raft-dependent internalization of the interleukin-1 receptor. Cell Signal 2016; 28:1520-9. [PMID: 27327966 DOI: 10.1016/j.cellsig.2016.06.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Revised: 06/16/2016] [Accepted: 06/16/2016] [Indexed: 12/27/2022]
Affiliation(s)
- Mark Windheim
- Institute of Biochemistry, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625 Hannover, Germany.
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25
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Deci MB, Ferguson SW, Liu M, Peterson DC, Koduvayur SP, Nguyen J. Utilizing clathrin triskelions as carriers for spatially controlled multi-protein display. Biomaterials 2016; 108:120-8. [PMID: 27627809 DOI: 10.1016/j.biomaterials.2016.08.044] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 08/20/2016] [Accepted: 08/26/2016] [Indexed: 10/21/2022]
Abstract
The simultaneous and spatially controlled display of different proteins on nanocarriers is a desirable property not often achieved in practice. Here, we report the use of clathrin triskelions as a versatile platform for functional protein display. We hypothesized that site-specific molecular epitope recognition would allow for effective and ordered protein attachment to clathrin triskelions. Clathrin binding peptides (CBPs) were genetically fused to mCherry and green fluorescent protein (GFP), expressed, and loaded onto clathrin triskelions by site-specific binding. Attachment was confirmed by surface plasmon resonance. mCherry fusion proteins modified with various CBPs displayed binding affinities between 470 nM and 287 μM for the clathrin triskelions. Simultaneous attachment of GFP-Wbox and mCherry-Cbox fusion constructs to the clathrin terminal domain was verified by Förster resonance energy transfer. The circulating half-lives, area under the curve, and the terminal half-lives of GFP and mCherry were significantly increased when attached to clathrin triskelions. Clathrin triskelion technology is useful for the development of versatile and multifunctional carriers for spatially controlled protein or peptide display with tremendous potential in nanotechnology, drug delivery, vaccine development, and targeted therapeutic applications.
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Affiliation(s)
- Michael B Deci
- Department of Pharmaceutical Sciences, School of Pharmacy, University at Buffalo, The State University of New York, Buffalo, NY, 14214, USA
| | - Scott W Ferguson
- Department of Pharmaceutical Sciences, School of Pharmacy, University at Buffalo, The State University of New York, Buffalo, NY, 14214, USA
| | - Maixian Liu
- Department of Pharmaceutical Sciences, School of Pharmacy, University at Buffalo, The State University of New York, Buffalo, NY, 14214, USA
| | - Damian C Peterson
- Department of Pharmaceutical Sciences, School of Pharmacy, University at Buffalo, The State University of New York, Buffalo, NY, 14214, USA
| | - Sujatha P Koduvayur
- Department of Electrical and Computer Engineering, Stevens Institute of Technology, Hoboken, NJ, 07030, USA
| | - Juliane Nguyen
- Department of Pharmaceutical Sciences, School of Pharmacy, University at Buffalo, The State University of New York, Buffalo, NY, 14214, USA.
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26
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Elkin SR, Oswald NW, Reed DK, Mettlen M, MacMillan JB, Schmid SL. Ikarugamycin: A Natural Product Inhibitor of Clathrin-Mediated Endocytosis. Traffic 2016; 17:1139-49. [PMID: 27392092 DOI: 10.1111/tra.12425] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 07/05/2016] [Accepted: 07/05/2016] [Indexed: 12/14/2022]
Abstract
Ikarugamycin (IKA) is a previously discovered antibiotic, which has been shown to inhibit the uptake of oxidized low-density lipoproteins in macrophages. Furthermore, several groups have previously used IKA to inhibit clathrin-mediated endocytosis (CME) in plant cell lines. However, detailed characterization of IKA has yet to be performed. Consequently, we performed biochemistry and microscopy experiments to further characterize the effects of IKA on CME. We show that IKA has an IC50 of 2.7 μm in H1299 cells and acutely inhibits CME, but not other endocytic pathways, in a panel of cell lines. Although long-term incubation with IKA has cytotoxic effects, the short-term inhibitory effects on CME are reversible. Thus, IKA can be a useful tool for probing routes of endocytic trafficking.
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Affiliation(s)
- Sarah R Elkin
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Nathaniel W Oswald
- Department of Biochemistry, UT Southwestern Medical Center, Dallas, TX, USA
| | - Dana K Reed
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Marcel Mettlen
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX, USA
| | - John B MacMillan
- Department of Biochemistry, UT Southwestern Medical Center, Dallas, TX, USA
| | - Sandra L Schmid
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX, USA.
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27
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Sobhy H. A Review of Functional Motifs Utilized by Viruses. Proteomes 2016; 4:proteomes4010003. [PMID: 28248213 PMCID: PMC5217368 DOI: 10.3390/proteomes4010003] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 01/07/2016] [Accepted: 01/13/2016] [Indexed: 01/05/2023] Open
Abstract
Short linear motifs (SLiM) are short peptides that facilitate protein function and protein-protein interactions. Viruses utilize these motifs to enter into the host, interact with cellular proteins, or egress from host cells. Studying functional motifs may help to predict protein characteristics, interactions, or the putative cellular role of a protein. In virology, it may reveal aspects of the virus tropism and help find antiviral therapeutics. This review highlights the recent understanding of functional motifs utilized by viruses. Special attention was paid to the function of proteins harboring these motifs, and viruses encoding these proteins. The review highlights motifs involved in (i) immune response and post-translational modifications (e.g., ubiquitylation, SUMOylation or ISGylation); (ii) virus-host cell interactions, including virus attachment, entry, fusion, egress and nuclear trafficking; (iii) virulence and antiviral activities; (iv) virion structure; and (v) low-complexity regions (LCRs) or motifs enriched with residues (Xaa-rich motifs).
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Affiliation(s)
- Haitham Sobhy
- Department of Molecular Biology, Umeå University, 901 87 Umeå, Sweden.
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28
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Ybe JA. Novel clathrin activity: developments in health and disease. Biomol Concepts 2015; 5:175-82. [PMID: 25372751 DOI: 10.1515/bmc-2013-0040] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Accepted: 02/18/2014] [Indexed: 12/21/2022] Open
Abstract
Clathrin self-assembles into a coat around vesicles filled with cargo such as nutrients, hormones, and proteins destined for degradation. Recent developments indicate clathrin is not a specialist, but is involved in different processes relevant to health and disease. Clathrin is used to strengthen centrosomes and mitotic spindles essential for chromosome segregation in cell division. In Wnt signaling, clathrin is a component of signalosomes on the plasma membrane needed to produce functional Wnt receptors. In glucose metabolism, a muscle-specific isoform, CHC22 clathrin, is key to the formation of storage compartments for GLUT4 receptor, and CHC22 dysfunction has been tied to type 2 diabetes. The activity of clathrin to self-assemble and to work with huntingtin-interacting proteins to organize actin is exploited by Listeria and enteropathic Escherichia coli in their infection pathways. Finally, there is an important connection between clathrin and human malignancies. Clathrin is argued to help transactivate tumor suppressor p53 that controls specific genes in DNA repair and apoptosis. However, this is debatable because trimeric clathrin must be made monomeric. To get insight on how the clathrin structure could be converted, the crystal structure of the trimerization domain is used in the development of the detrimerization switch hypothesis. This novel hypothesis will be relevant if connections continue to be found between CHC17 and p53 anti-cancer activity in the nucleus.
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29
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Zhuo Y, Cano KE, Wang L, Ilangovan U, Hinck AP, Sousa R, Lafer EM. Nuclear Magnetic Resonance Structural Mapping Reveals Promiscuous Interactions between Clathrin-Box Motif Sequences and the N-Terminal Domain of the Clathrin Heavy Chain. Biochemistry 2015; 54:2571-80. [PMID: 25844500 PMCID: PMC4429812 DOI: 10.1021/acs.biochem.5b00065] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
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The recruitment and organization
of clathrin at endocytic sites
first to form coated pits and then clathrin-coated vesicles depend
on interactions between the clathrin N-terminal domain (TD) and multiple
clathrin binding sequences on the cargo adaptor and accessory proteins
that are concentrated at such sites. Up to four distinct protein binding
sites have been proposed to be present on the clathrin TD, with each
site proposed to interact with a distinct clathrin binding motif.
However, an understanding of how such interactions contribute to clathrin
coat assembly must take into account observations that any three of
these four sites on clathrin TD can be mutationally ablated without
causing loss of clathrin-mediated endocytosis. To take an unbiased
approach to mapping binding sites for clathrin-box motifs on clathrin
TD, we used isothermal titration calorimetry (ITC) and nuclear magnetic
resonance spectroscopy. Our ITC experiments revealed that a canonical
clathrin-box motif peptide from the AP-2 adaptor binds to clathrin
TD with a stoichiometry of 3:1. Assignment of 90% of the total visible
amide resonances in the TROSY-HSQC spectrum of 13C-, 2H-, and 15N-labeled TD40 allowed us to map these
three binding sites by analyzing the chemical shift changes as clathrin-box
motif peptides were titrated into clathrin TD. We found that three
different clathrin-box motif peptides can each simultaneously bind
not only to the previously characterized clathrin-box site but also
to the W-box site and the β-arrestin splice loop site on a single
TD. The promiscuity of these binding sites can help explain why their
mutation does not lead to larger effects on clathrin function and
suggests a mechanism by which clathrin may be transferred between
different proteins during the course of an endocytic event.
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Affiliation(s)
- Yue Zhuo
- Department of Biochemistry and Center for Biomedical Neuroscience, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229, United States
| | - Kristin E Cano
- Department of Biochemistry and Center for Biomedical Neuroscience, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229, United States
| | - Liping Wang
- Department of Biochemistry and Center for Biomedical Neuroscience, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229, United States
| | - Udayar Ilangovan
- Department of Biochemistry and Center for Biomedical Neuroscience, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229, United States
| | - Andrew P Hinck
- Department of Biochemistry and Center for Biomedical Neuroscience, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229, United States
| | - Rui Sousa
- Department of Biochemistry and Center for Biomedical Neuroscience, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229, United States
| | - Eileen M Lafer
- Department of Biochemistry and Center for Biomedical Neuroscience, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229, United States
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30
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Totta P, Pesiri V, Enari M, Marino M, Acconcia F. Clathrin Heavy Chain Interacts With Estrogen Receptor α and Modulates 17β-Estradiol Signaling. Mol Endocrinol 2015; 29:739-55. [PMID: 25860340 DOI: 10.1210/me.2014-1385] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
17β-estradiol (E2)-induced signaling and control of estrogen receptor (ER)α degradation both play a major role in breast cancer cell proliferation. We recently reported the involvement of lysosomal function in both E2-dependent ERα breakdown and E2-induced cell proliferation and thus hypothesized a role for endocytic proteins in ERα signaling. An small interfering RNA screen identified proteins that regulate intracellular endocytic traffic and whose silencing alters E2-induced ERα degradation. One such protein was the clathrin heavy chain (CHC), whose role in E2:ERα signaling to cell proliferation is unknown. Here, we show that CHC physically interacts with ERα in the cytoplasm of breast cancer cells and regulates E2-induced cell proliferation. Surprisingly, the CHC:ERα interaction is required to sustain E2 signaling but is dispensable for ERα degradation. Our data also demonstrate that many membrane trafficking proteins contribute to the regulation of ERα degradation, thus unraveling the contribution of endocytic proteins in E2:ERα signaling.
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Affiliation(s)
- Pierangela Totta
- Department of Sciences (P.T., V.P., M.M., F.A.), Section Biomedical Sciences and Technology, University Roma Tre, I-00146, Rome, Italy; and Division of Refractory Cancer Research (M.E.), National Cancer Center Research Institute, Chuo-ku, Tokyo 104-0045, Japan
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31
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Dutta D, Donaldson JG. Search for inhibitors of endocytosis: Intended specificity and unintended consequences. CELLULAR LOGISTICS 2014; 2:203-208. [PMID: 23538558 PMCID: PMC3607622 DOI: 10.4161/cl.23967] [Citation(s) in RCA: 326] [Impact Index Per Article: 32.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
We discuss here the variety of approaches that have been taken to inhibit different forms of endocytosis. Typically, both non-specific and specific chemical inhibitors of endocytosis are tried in order to “classify” entry of a new plasma membrane protein into one of the various types of endocytosis. This classification can be confirmed through genetic approaches of protein depletion or overexpression of mutants of known endocytosis machinery components. Although some new compounds have been designed to be selective in biochemical assays, we caution investigators to be alert to the unintended consequences that sometimes arise when these compounds are applied to intact cells.
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Affiliation(s)
- Dipannita Dutta
- Cell Biology & Physiology Center; National Heart, Lung, and Blood Institute; National Institutes of Health; Bethesda, MD USA
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32
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Abstract
Small molecule inhibitors of clathrin-mediated endocytosis are highly desired for the dissection of membrane trafficking pathways in the lab and for potential use as anti-infectives in the clinic. One inhibition strategy is to prevent clathrin from contacting adaptor proteins so that clathrin-mediated endocytosis cannot occur. “Pitstop” compounds have been developed that block only one of the four functional interaction sites on the N-terminal domain of clathrin heavy chain. Despite this limitation, Pitstop 2 causes profound inhibition of clathrin-mediated endocytosis. In this study, we probed for non-specific activity of Pitstop 2 by examining its action in cells expressing clathrin heavy chain harbouring mutations in the N-terminal domain interaction sites. We conclude that the inhibition observed with this compound is due to non-specificity, i.e. it causes inhibition away from its proposed mode of action. We recommend that these compounds be used with caution in cells and that they should not be used to conclude anything of the function of clathrin's N-terminal domain.
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Affiliation(s)
- Anna K Willox
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool L69 3BX, UK
| | - Yasmina M E Sahraoui
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool L69 3BX, UK
| | - Stephen J Royle
- Department of Cellular and Molecular Physiology, Institute of Translational Medicine, University of Liverpool, Liverpool L69 3BX, UK Division of Biomedical Cell Biology, Warwick Medical School, Gibbet Hill Road, Coventry CV4 7AL, UK
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33
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Stabley D, Retterer S, Marshall S, Salaita K. Manipulating the lateral diffusion of surface-anchored EGF demonstrates that receptor clustering modulates phosphorylation levels. Integr Biol (Camb) 2013; 5:659-68. [PMID: 23416883 DOI: 10.1039/c3ib20239a] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Upon activation, the epidermal growth factor (EGF) receptor becomes phosphorylated and triggers a vast signaling network that has profound effects on cell growth. The EGF receptor is observed to assemble into clusters after ligand binding and tyrosine kinase autophosphorylation, but the role of these assemblies in the receptor signaling pathway remains unclear. To address this question, we measured the phosphorylation of EGFR when the EGF ligand was anchored onto laterally mobile and immobile surfaces. We found that cells generated clusters of ligand-receptor complex on mobile EGF surfaces, and displayed a lower ratio of phosphorylated EGFR to EGF when compared to immobilized EGF that is unable to cluster. This result was verified by tuning the lateral assembly of ligand-receptor complexes on the surface of living cells using patterned supported lipid bilayers. Nanoscale metal lines fabricated into the supported membrane constrained lipid diffusion and EGF receptor assembly into micron and sub-micron scale corrals. Single cell analysis indicated that clustering impacts EGF receptor activation, and larger clusters (>1 μm(2)) of ligand-receptor complex generated lower EGF receptor phosphorylation per ligand than smaller assemblies (<1 μm(2)) in HCC1143 cells that were engaged to ligand-functionalized surfaces. We investigated the mechanism of EGFR clustering by treating cells with compounds that disrupt the cytoskeleton (Latrunculin B), clathrin-mediated endocytosis (Pitstop2), and inhibit EGFR activation (Gefitinib). These results help elucidate the nature of large-scale EGFR clustering, thus underscoring the general significance of receptor spatial organization in tuning biochemical function.
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Affiliation(s)
- D Stabley
- Department of Chemistry, Emory University, Atlanta, GA, USA
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34
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Cleyrat C, Darehshouri A, Anderson KL, Page C, Lidke DS, Volkmann N, Hanein D, Wilson BS. The architectural relationship of components controlling mast cell endocytosis. J Cell Sci 2013; 126:4913-25. [PMID: 23986485 DOI: 10.1242/jcs.128876] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Eukaryotic cells use multiple routes for receptor internalization. Here, we examine the topographical relationships of clathrin-dependent and clathrin-independent endocytic structures on the plasma membranes of leukemia-derived mast cells. The high affinity IgE receptor (FcεRI) utilizes both pathways, whereas transferrin receptor serves as a marker for the classical clathrin-mediated endocytosis pathway. Both receptors were tracked by live-cell imaging in the presence or absence of inhibitors that established their differential dependence on specific endocytic adaptor proteins. The topology of antigen-bound FcεRI, clathrin, dynamin, Arf6 and Eps15-positive structures were analyzed by 2D and 3D immunoelectron microscopy techniques, revealing their remarkable spatial relationships and unique geometry. We conclude that the mast cell plasma membrane has multiple specialized domains for endocytosis. Their close proximity might reflect shared components, such as lipids and adaptor proteins, that facilitate inward membrane curvature. Intersections between these specialized domains might represent sorting stations that direct cargo to specific endocytic pathways.
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Affiliation(s)
- Cédric Cleyrat
- Department of Pathology University of New Mexico Health Sciences Center, Albuquerque, NM 87131, USA
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35
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Hirst J, Borner GHH, Edgar J, Hein MY, Mann M, Buchholz F, Antrobus R, Robinson MS. Interaction between AP-5 and the hereditary spastic paraplegia proteins SPG11 and SPG15. Mol Biol Cell 2013; 24:2558-69. [PMID: 23825025 PMCID: PMC3744948 DOI: 10.1091/mbc.e13-03-0170] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The AP-5 complex is a recently identified but evolutionarily ancient member of the family of heterotetrameric adaptor proteins (AP complexes). It is associated with two proteins that are mutated in patients with hereditary spastic paraplegia, SPG11 and SPG15. Here we show that the four AP-5 subunits can be coimmunoprecipitated with SPG11 and SPG15, both from cytosol and from detergent-extracted membranes, with a stoichiometry of ∼1:1:1:1:1:1. Knockdowns of SPG11 or SPG15 phenocopy knockdowns of AP-5 subunits: all six knockdowns cause the cation-independent mannose 6-phosphate receptor to become trapped in clusters of early endosomes. In addition, AP-5, SPG11, and SPG15 colocalize on a late endosomal/lysosomal compartment. Both SPG11 and SPG15 have predicted secondary structures containing α-solenoids related to those of clathrin heavy chain and COPI subunits. SPG11 also has an N-terminal, β-propeller-like domain, which interacts in vitro with AP-5. We propose that AP-5, SPG15, and SPG11 form a coat-like complex, with AP-5 involved in protein sorting, SPG15 facilitating the docking of the coat onto membranes by interacting with PI3P via its FYVE domain, and SPG11 (possibly together with SPG15) forming a scaffold.
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Affiliation(s)
- Jennifer Hirst
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, United Kingdom.
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36
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Zlatic SA, Grossniklaus EJ, Ryder PV, Salazar G, Mattheyses AL, Peden AA, Faundez V. Chemical-genetic disruption of clathrin function spares adaptor complex 3-dependent endosome vesicle biogenesis. Mol Biol Cell 2013; 24:2378-88. [PMID: 23761069 PMCID: PMC3727930 DOI: 10.1091/mbc.e12-12-0860] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Clathrin–AP-3 association is dispensable for AP-3 vesicle budding from endosomes, which suggests that AP-3–clathrin interactions differ from those by which AP-1 and AP-2 adaptors productively engage clathrin in vesicle biogenesis. A role for clathrin in AP-3–dependent vesicle biogenesis has been inferred from biochemical interactions and colocalization between this adaptor and clathrin. The functionality of these molecular associations, however, is controversial. We comprehensively explore the role of clathrin in AP-3–dependent vesicle budding, using rapid chemical-genetic perturbation of clathrin function with a clathrin light chain–FKBP chimera oligomerizable by the drug AP20187. We find that AP-3 interacts and colocalizes with endogenous and recombinant FKBP chimeric clathrin polypeptides in PC12-cell endosomes. AP-3 displays, however, a divergent behavior from AP-1, AP-2, and clathrin chains. AP-3 cofractionates with clathrin-coated vesicle fractions isolated from PC12 cells even after clathrin function is acutely inhibited by AP20187. We predicted that AP20187 would inhibit AP-3 vesicle formation from endosomes after a brefeldin A block. AP-3 vesicle formation continued, however, after brefeldin A wash-out despite impairment of clathrin function by AP20187. These findings indicate that AP-3–clathrin association is dispensable for endosomal AP-3 vesicle budding and suggest that endosomal AP-3–clathrin interactions differ from those by which AP-1 and AP-2 adaptors productively engage clathrin in vesicle biogenesis.
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37
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Interface-resolved network of protein-protein interactions. PLoS Comput Biol 2013; 9:e1003065. [PMID: 23696724 PMCID: PMC3656101 DOI: 10.1371/journal.pcbi.1003065] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Accepted: 04/08/2013] [Indexed: 12/01/2022] Open
Abstract
We define an interface-interaction network (IIN) to capture the specificity and competition between protein-protein interactions (PPI). This new type of network represents interactions between individual interfaces used in functional protein binding and thereby contains the detail necessary to describe the competition and cooperation between any pair of binding partners. Here we establish a general framework for the construction of IINs that merges computational structure-based interface assignment with careful curation of available literature. To complement limited structural data, the inclusion of biochemical data is critical for achieving the accuracy and completeness necessary to analyze the specificity and competition between the protein interactions. Firstly, this procedure provides a means to clarify the information content of existing data on purported protein interactions and to remove indirect and spurious interactions. Secondly, the IIN we have constructed here for proteins involved in clathrin-mediated endocytosis (CME) exhibits distinctive topological properties. In contrast to PPI networks with their global and relatively dense connectivity, the fragmentation of the IIN into distinctive network modules suggests that different functional pressures act on the evolution of its topology. Large modules in the IIN are formed by interfaces sharing specificity for certain domain types, such as SH3 domains distributed across different proteins. The shared and distinct specificity of an interface is necessary for effective negative and positive design of highly selective binding targets. Lastly, the organization of detailed structural data in a network format allows one to identify pathways of specific binding interactions and thereby predict effects of mutations at specific surfaces on a protein and of specific binding inhibitors, as we explore in several examples. Overall, the endocytosis IIN is remarkably complex and rich in features masked in the coarser PPI, and collects relevant detail of protein association in a readily interpretable format. Much of the work inside the cell is carried out by proteins interacting with other proteins. Each edge in a protein-protein interaction network reflects these functional interactions and each node a separate protein, creating a complex structure that nevertheless follows well-established global and local patterns related to robust protein function. However, this network is not detailed enough to assess whether a particular protein can bind multiple interaction partners simultaneously through distinct interfaces, or whether the partners targeting a specific interface share similar structural or chemical properties. By breaking each protein node into its constituent interface nodes, we generate and assess such a detailed new network. To sample protein binding interactions broadly and accurately beyond those seen in crystal structures, our method combines computational interface assignment with data from biochemical studies. Using this approach we are able to assign interfaces to the majority of known interactions between proteins involved in the clathrin-mediated endocytosis pathway in yeast. Analysis of this interface-interaction network provides novel insights into the functional specificity of protein interactions, and highlights elements of cooperativity and competition among the proteins. By identifying diverse multi-protein complexes, interface-interaction networks also provide a map for targeted drug development.
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38
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Dutta D, Williamson CD, Cole NB, Donaldson JG. Pitstop 2 is a potent inhibitor of clathrin-independent endocytosis. PLoS One 2012; 7:e45799. [PMID: 23029248 PMCID: PMC3448704 DOI: 10.1371/journal.pone.0045799] [Citation(s) in RCA: 158] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Accepted: 08/24/2012] [Indexed: 12/13/2022] Open
Abstract
Clathrin independent endocytosis (CIE) is a form of endocytosis present in all cells that mediates the entry of nutrients, macromolecules and membrane proteins into cells. When compared to clathrin-dependent endocytosis (CDE), however, much less is known about the machinery involved in forming CIE endosomes. One way to distinguish CIE from CDE has been to deplete cells of coat proteins involved in CDE such as clathrin or the dynamin GTPase, leading to a block of CDE but not CIE. A drawback of such genetic manipulations is that depletion of proteins important for mediating CDE over a period of days can have complex indirect effects on cellular function. The identification of chemical compounds that specifically and rapidly block CDE or CIE would facilitate the determination of whether a process involved CDE or CIE. To date, all of those compounds have targeted CDE. Dynasore and the dynoles specifically target and block dynamin activity thus inhibiting CDE but not most forms of CIE. Recently, a new compound called pitstop 2 was identified as an inhibitor of the interaction of amphiphysin with the amino terminal domain of clathrin, and shown to inhibit CDE in cells. Here we show that pitstop 2 is also a potent inhibitor of CIE. The effects of pitstop 2 are not restricted to inhibition of clathrin since knockdown of clathrin fails to rescue the inhibition of endocytosis of CIE proteins by the drug. Thus pitstop 2 has additional cellular targets besides the amino terminal domain of clathrin and thus cannot be used to distinguish CIE from CDE.
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Affiliation(s)
- Dipannita Dutta
- Laboratory of Cell Biology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Chad D. Williamson
- Laboratory of Cell Biology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Nelson B. Cole
- Laboratory of Cell Biology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Julie G. Donaldson
- Laboratory of Cell Biology, National Heart, Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail:
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39
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Jackson LP, Kümmel D, Reinisch KM, Owen DJ. Structures and mechanisms of vesicle coat components and multisubunit tethering complexes. Curr Opin Cell Biol 2012; 24:475-83. [PMID: 22728063 PMCID: PMC3425711 DOI: 10.1016/j.ceb.2012.05.013] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Accepted: 05/23/2012] [Indexed: 11/17/2022]
Abstract
Eukaryotic cells face a logistical challenge in ensuring prompt and precise delivery of vesicular cargo to specific organelles within the cell. Coat protein complexes select cargo and initiate vesicle formation, while multisubunit tethering complexes participate in the delivery of vesicles to target membranes. Understanding these macromolecular assemblies has greatly benefited from their structural characterization. Recent structural data highlight principles in coat recruitment and uncoating in both the endocytic and retrograde pathways, and studies on the architecture of tethering complexes provide a framework for how they might link vesicles to the respective acceptor compartments and the fusion machinery.
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Affiliation(s)
- Lauren P Jackson
- Cambridge Institute for Medical Research, Department of Clinical Biochemistry, University of Cambridge, Cambridge CB2 0XY, UK.
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40
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Abstract
Clathrin is considered the prototype vesicle coat protein whose self-assembly mediates sorting of membrane cargo and recruitment of lipid modifiers. Detailed knowledge of clathrin biochemistry, structure, and interacting proteins has accumulated since the first observation, almost 50 years ago, of its role in receptor-mediated endocytosis of yolk protein. This review summarizes that knowledge, and focuses on properties of the clathrin heavy and light chain subunits and interaction of the latter with Hip proteins, to address the diversity of clathrin function beyond conventional receptor-mediated endocytosis. The distinct functions of the two human clathrin isoforms (CHC17 and CHC22) are discussed, highlighting CHC22's specialized involvement in traffic of the GLUT4 glucose transporter and consequent role in human glucose metabolism. Analysis of clathrin light chain function and interaction with the actin-binding Hip proteins during bacterial infection defines a novel actin-organizing function for CHC17 clathrin. By considering these diverse clathrin functions, along with intracellular sorting roles and influences on mitosis, further relevance of clathrin function to human health and disease is established.
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Affiliation(s)
- Frances M Brodsky
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, California 94143-0552, USA.
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