1
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Ayagama T, Charles PD, Bose SJ, Boland B, Priestman DA, Aston D, Berridge G, Fischer R, Cribbs AP, Song Q, Mirams GR, Amponsah K, Heather L, Galione A, Herring N, Kramer H, Capel RA, Platt FM, Schotten U, Verheule S, Burton RA. Compartmentalization proteomics revealed endolysosomal protein network changes in a goat model of atrial fibrillation. iScience 2024; 27:109609. [PMID: 38827406 PMCID: PMC11141153 DOI: 10.1016/j.isci.2024.109609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 02/07/2024] [Accepted: 03/25/2024] [Indexed: 06/04/2024] Open
Abstract
Endolysosomes (EL) are known for their role in regulating both intracellular trafficking and proteostasis. EL facilitate the elimination of damaged membranes, protein aggregates, membranous organelles and play an important role in calcium signaling. The specific role of EL in cardiac atrial fibrillation (AF) is not well understood. We isolated atrial EL organelles from AF goat biopsies and conducted a comprehensive integrated omics analysis to study the EL-specific proteins and pathways. We also performed electron tomography, protein and enzyme assays on these biopsies. Our results revealed the upregulation of the AMPK pathway and the expression of EL-specific proteins that were not found in whole tissue lysates, including GAA, DYNLRB1, CLTB, SIRT3, CCT2, and muscle-specific HSPB2. We also observed structural anomalies, such as autophagic-vacuole formation, irregularly shaped mitochondria, and glycogen deposition. Our results provide molecular information suggesting EL play a role in AF disease process over extended time frames.
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Affiliation(s)
- Thamali Ayagama
- Department of Pharmacology, University of Oxford, Oxford, UK
| | | | - Samuel J. Bose
- Department of Pharmacology, University of Oxford, Oxford, UK
| | - Barry Boland
- Department of Pharmacology and Therapeutics, University College Cork, Cork, Ireland
| | | | - Daniel Aston
- Department of Anaesthesia and Critical Care, Royal Papworth Hospital NHS Foundation Trust, Papworth Road, Cambridge CB2 0AY, UK
| | | | - Roman Fischer
- Target Discovery Institute, University of Oxford, Oxford, UK
| | - Adam P. Cribbs
- Nuffield Department of Orthopaedics Rheumatology and Musculoskeletal Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, Botnar Research Centre, University of Oxford, Headington OX3 7LD, UK
| | - Qianqian Song
- Department of Pharmacology, University of Oxford, Oxford, UK
| | - Gary R. Mirams
- Centre for Mathematical Medicine & Biology, Mathematical Sciences, University of Nottingham, Nottingham NG7 2RD, UK
| | - Kwabena Amponsah
- Centre for Mathematical Medicine & Biology, Mathematical Sciences, University of Nottingham, Nottingham NG7 2RD, UK
| | - Lisa Heather
- Department of Physiology, Anatomy and Genetics, , University of Oxford, South Park Road, Oxford OX1 3PT, UK
| | - Antony Galione
- Department of Pharmacology, University of Oxford, Oxford, UK
| | - Neil Herring
- Department of Physiology, Anatomy and Genetics, , University of Oxford, South Park Road, Oxford OX1 3PT, UK
| | - Holger Kramer
- Mass spectrometry Facility, The MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | | | | | - Ulrich Schotten
- Departments of Physiology and Cardiology, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, the Netherlands
| | - Sander Verheule
- Departments of Physiology and Cardiology, Cardiovascular Research Institute Maastricht, Maastricht University, Maastricht, the Netherlands
| | - Rebecca A.B. Burton
- Department of Pharmacology, University of Oxford, Oxford, UK
- University of Liverpool, Department of Pharmacology and Therapeutics, Institute of Systems, Molecular and Integrative Biology, Liverpool, UK
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Spada SJ, Rose KM, Sette P, O'Connor SK, Dussupt V, Siddartha Yerramilli V, Nagashima K, Sjoelund VH, Cruz P, Kabat J, Ganesan S, Smelkinson M, Nita-Lazar A, Hoyt F, Scarlata S, Hirsch V, Best SM, Grigg ME, Bouamr F. Human ESCRT-I and ALIX function as scaffolding helical filaments in vivo. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.01.592080. [PMID: 38903125 PMCID: PMC11188096 DOI: 10.1101/2024.05.01.592080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/22/2024]
Abstract
The Endosomal Sorting Complex Required for Transport (ESCRT) is an evolutionarily conserved machinery that performs reverse-topology membrane scission in cells universally required from cytokinesis to budding of enveloped viruses. Upstream acting ESCRT-I and ALIX control these events and link recruitment of viral and cellular partners to late-acting ESCRT-III CHMP4 through incompletely understood mechanisms. Using structure-function analyses combined with super-resolution imaging, we show that ESCRT-I and ALIX function as distinct helical filaments in vivo . Together, they are essential for optimal structural scaffolding of HIV-1 nascent virions, the retention of viral and human genomes through defined functional interfaces, and recruitment of CHMP4 that itself assembles into corkscrew-like filaments intertwined with ESCRT-I or ALIX helices. Disruption of filament assembly or their conformationally clustered RNA binding interfaces in human cells impaired membrane abscission, resulted in major structural instability and leaked nucleic acid from nascent virions and nuclear envelopes. Thus, ESCRT-I and ALIX function as helical filaments in vivo and serve as both nucleic acid-dependent structural scaffolds as well as ESCRT-III assembly templates. Significance statement When cellular membranes are dissolved or breached, ESCRT is rapidly deployed to repair membranes to restore the integrity of intracellular compartments. Membrane sealing is ensured by ESCRT-III filaments assembled on the inner face of membrane; a mechanism termed inverse topology membrane scission. This mechanism, initiated by ESCRT-I and ALIX, is universally necessary for cytokinesis, wound repair, budding of enveloped viruses, and more. We show ESCRT-I and ALIX individually oligomerize into helical filaments that cluster newly discovered nucleic acid-binding interfaces and scaffold-in genomes within nascent virions and nuclear envelopes. These oligomers additionally appear to serve as ideal templates for ESCRT-III polymerization, as helical filaments of CHMP4B were found intertwined ESCRT-I or ALIX filaments in vivo . Similarly, corkscrew-like filaments of ALIX are also interwoven with ESCRT-I, supporting a model of inverse topology membrane scission that is synergistically reinforced by inward double filament scaffolding.
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3
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Song C, Xie K, Chen H, Xu S, Mao H. Wheat ESCRT-III protein TaSAL1 regulates male gametophyte transmission and controls tillering and heading date. JOURNAL OF EXPERIMENTAL BOTANY 2024; 75:2372-2384. [PMID: 38206130 DOI: 10.1093/jxb/erae012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Accepted: 01/10/2024] [Indexed: 01/12/2024]
Abstract
Charged multivesicular protein 1 (CHMP1) is a member of the endosomal sorting complex required for transport-III (ESCRT-III) complex that targets membrane localized signaling receptors to intralumenal vesicles in the multivesicular body of the endosome and eventually to the lysosome for degradation. Although CHMP1 plays roles in various plant growth and development processes, little is known about its function in wheat. In this study, we systematically analysed the members of the ESCRT-III complex in wheat (Triticum aestivum) and found that their orthologs were highly conserved in eukaryotic evolution. We identified CHMP1 homologous genes, TaSAL1s, and found that they were constitutively expressed in wheat tissues and essential for plant reproduction. Subcellular localization assays showed these proteins aggregated with and closely associated with the endoplasmic reticulum when ectopically expressed in tobacco leaves. We also found these proteins were toxic and caused leaf death. A genetic and reciprocal cross analysis revealed that TaSAL1 leads to defects in male gametophyte biogenesis. Moreover, phenotypic and metabolomic analysis showed that TaSAL1 may regulate tillering and heading date through phytohormone pathways. Overall, our results highlight the role of CHMP1 in wheat, particularly in male gametophyte biogenesis, with implications for improving plant growth and developing new strategies for plant breeding and genetic engineering.
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Affiliation(s)
- Chengxiang Song
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Kaidi Xie
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Hao Chen
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Shuhao Xu
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
| | - Hailiang Mao
- National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China
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4
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Parihar K, Ko SH, Bradley R, Taylor P, Ramakrishnan N, Baumgart T, Guo W, Weaver VM, Janmey PA, Radhakrishnan R. Free energy calculations for membrane morphological transformations and insights to physical biology and oncology. Methods Enzymol 2024; 701:359-386. [PMID: 39025576 PMCID: PMC11258396 DOI: 10.1016/bs.mie.2024.03.028] [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] [Indexed: 07/20/2024]
Abstract
In this chapter, we aim to bridge basic molecular and cellular principles surrounding membrane curvature generation with rewiring of cellular signals in cancer through multiscale models. We describe a general framework that integrates signaling with other cellular functions like trafficking, cell-cell and cell-matrix adhesion, and motility. The guiding question in our approach is: how does a physical change in cell membrane configuration caused by external stimuli (including those by the extracellular microenvironment) alter trafficking, signaling and subsequent cell fate? We answer this question by constructing a modeling framework based on stochastic spatial continuum models of cell membrane deformations. We apply this framework to explore the link between trafficking, signaling in the tumor microenvironment, and cell fate. At each stage, we aim to connect the results of our predictions with cellular experiments.
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Affiliation(s)
- Kshitiz Parihar
- Department of Chemical and Biomolecular Engineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, United States
| | - Seung-Hyun Ko
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, United States
| | - Ryan Bradley
- Department of Chemical and Biomolecular Engineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, United States
| | - Phillip Taylor
- Department of Chemical and Biomolecular Engineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, United States
| | - N Ramakrishnan
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, United States
| | - Tobias Baumgart
- Department of Chemistry, School of Arts & Sciences, University of Pennsylvania, Philadelphia, PA, United States
| | - Wei Guo
- Department of Biology, School of Arts & Sciences, University of Pennsylvania, Philadelphia, PA, United States
| | - Valerie M Weaver
- Department of Surgery, Center for Bioengineering and Tissue Regeneration, University of California, San Francisco, San Francisco, CA, United States
| | - Paul A Janmey
- Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, United States; Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Ravi Radhakrishnan
- Department of Chemical and Biomolecular Engineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, United States; Department of Bioengineering, School of Engineering and Applied Science, University of Pennsylvania, Philadelphia, PA, United States.
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5
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Makarova KS, Tobiasson V, Wolf YI, Lu Z, Liu Y, Zhang S, Krupovic M, Li M, Koonin EV. Diversity, origin, and evolution of the ESCRT systems. mBio 2024; 15:e0033524. [PMID: 38380930 PMCID: PMC10936438 DOI: 10.1128/mbio.00335-24] [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: 02/05/2024] [Accepted: 02/06/2024] [Indexed: 02/22/2024] Open
Abstract
Endosomal sorting complexes required for transport (ESCRT) play key roles in protein sorting between membrane-bounded compartments of eukaryotic cells. Homologs of many ESCRT components are identifiable in various groups of archaea, especially in Asgardarchaeota, the archaeal phylum that is currently considered to include the closest relatives of eukaryotes, but not in bacteria. We performed a comprehensive search for ESCRT protein homologs in archaea and reconstructed ESCRT evolution using the phylogenetic tree of Vps4 ATPase (ESCRT IV) as a scaffold and using sensitive protein sequence analysis and comparison of structural models to identify previously unknown ESCRT proteins. Several distinct groups of ESCRT systems in archaea outside of Asgard were identified, including proteins structurally similar to ESCRT-I and ESCRT-II, and several other domains involved in protein sorting in eukaryotes, suggesting an early origin of these components. Additionally, distant homologs of CdvA proteins were identified in Thermoproteales which are likely components of the uncharacterized cell division system in these archaea. We propose an evolutionary scenario for the origin of eukaryotic and Asgard ESCRT complexes from ancestral building blocks, namely, the Vps4 ATPase, ESCRT-III components, wH (winged helix-turn-helix fold) and possibly also coiled-coil, and Vps28-like domains. The last archaeal common ancestor likely encompassed a complex ESCRT system that was involved in protein sorting. Subsequent evolution involved either simplification, as in the TACK superphylum, where ESCRT was co-opted for cell division, or complexification as in Asgardarchaeota. In Asgardarchaeota, the connection between ESCRT and the ubiquitin system that was previously considered a eukaryotic signature was already established.IMPORTANCEAll eukaryotic cells possess complex intracellular membrane organization. Endosomal sorting complexes required for transport (ESCRT) play a central role in membrane remodeling which is essential for cellular functionality in eukaryotes. Recently, it has been shown that Asgard archaea, the archaeal phylum that includes the closest known relatives of eukaryotes, encode homologs of many components of the ESCRT systems. We employed protein sequence and structure comparisons to reconstruct the evolution of ESCRT systems in archaea and identified several previously unknown homologs of ESCRT subunits, some of which can be predicted to participate in cell division. The results of this reconstruction indicate that the last archaeal common ancestor already encoded a complex ESCRT system that was involved in protein sorting. In Asgard archaea, ESCRT systems evolved toward greater complexity, and in particular, the connection between ESCRT and the ubiquitin system that was previously considered a eukaryotic signature was established.
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Affiliation(s)
- Kira S. Makarova
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, Maryland, USA
| | - Victor Tobiasson
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, Maryland, USA
| | - Yuri I. Wolf
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, Maryland, USA
| | - Zhongyi Lu
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Yang Liu
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Siyu Zhang
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Mart Krupovic
- Archaeal Virology Unit, Institut Pasteur, Université de Paris, Paris, France
| | - Meng Li
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Eugene V. Koonin
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, Maryland, USA
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6
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Makarova KS, Tobiasson V, Wolf YI, Lu Z, Liu Y, Zhang S, Krupovic M, Li M, Koonin EV. Diversity, Origin and Evolution of the ESCRT Systems. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.06.579148. [PMID: 38903064 PMCID: PMC11188069 DOI: 10.1101/2024.02.06.579148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/22/2024]
Abstract
Endosomal Sorting Complexes Required for Transport (ESCRT) play key roles in protein sorting between membrane-bounded compartments of eukaryotic cells. Homologs of many ESCRT components are identifiable in various groups of archaea, especially in Asgardarchaeota, the archaeal phylum that is currently considered to include the closest relatives of eukaryotes, but not in bacteria. We performed a comprehensive search for ESCRT protein homologs in archaea and reconstructed ESCRT evolution using the phylogenetic tree of Vps4 ATPase (ESCRT IV) as a scaffold, using sensitive protein sequence analysis and comparison of structural models to identify previously unknown ESCRT proteins. Several distinct groups of ESCRT systems in archaea outside of Asgard were identified, including proteins structurally similar to ESCRT-I and ESCRT-II, and several other domains involved in protein sorting in eukaryotes, suggesting an early origin of these components. Additionally, distant homologs of CdvA proteins were identified in Thermoproteales which are likely components of the uncharacterized cell division system in these archaea. We propose an evolutionary scenario for the origin of eukaryotic and Asgard ESCRT complexes from ancestral building blocks, namely, the Vps4 ATPase, ESCRT-III components, wH (winged helix-turn-helix fold) and possibly also coiled-coil, and Vps28-like domains. The Last Archaeal Common Ancestor likely encompassed a complex ESCRT system that was involved in protein sorting. Subsequent evolution involved either simplification, as in the TACK superphylum, where ESCRT was co-opted for cell division, or complexification as in Asgardarchaeota. In Asgardarchaeota, the connection between ESCRT and the ubiquitin system that was previously considered a eukaryotic signature was already established.
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Affiliation(s)
- Kira S. Makarova
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, MD 20894, USA
| | - Victor Tobiasson
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, MD 20894, USA
| | - Yuri I. Wolf
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, MD 20894, USA
| | - Zhongyi Lu
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
| | - Yang Liu
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
| | - Siyu Zhang
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
| | - Mart Krupovic
- Archaeal Virology Unit, Institut Pasteur, Université de Paris, F-75015 Paris, France
| | - Meng Li
- Archaeal Biology Center, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
- Shenzhen Key Laboratory of Marine Microbiome Engineering, Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
| | - Eugene V Koonin
- National Center for Biotechnology Information, National Library of Medicine, Bethesda, MD 20894, USA
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7
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Hudait A, Hurley JH, Voth GA. Dynamics of upstream ESCRT organization at the HIV-1 budding site. Biophys J 2023; 122:2655-2674. [PMID: 37218128 PMCID: PMC10397573 DOI: 10.1016/j.bpj.2023.05.020] [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: 12/09/2022] [Revised: 03/27/2023] [Accepted: 05/11/2023] [Indexed: 05/24/2023] Open
Abstract
In the late stages of the HIV-1 life cycle, membrane localization and self-assembly of Gag polyproteins induce membrane deformation and budding. Release of the virion requires direct interaction between immature Gag lattice and upstream ESCRT machinery at the viral budding site, followed by assembly of downstream ESCRT-III factors, culminating in membrane scission. However, molecular details of upstream ESCRT assembly dynamics at the viral budding site remain unclear. In this work, using coarse-grained (CG) molecular dynamics (MD) simulations, we investigated the interactions between Gag, ESCRT-I, ESCRT-II, and membrane to delineate the dynamical mechanisms by which upstream ESCRTs assemble templated by late-stage immature Gag lattice. We first systematically derived "bottom-up" CG molecular models and interactions of upstream ESCRT proteins from experimental structural data and extensive all-atom MD simulations. Using these molecular models, we performed CG MD simulations of ESCRT-I oligomerization and ESCRT-I/II supercomplex formation at the neck of the budding virion. Our simulations demonstrate that ESCRT-I can effectively oligomerize to higher-order complexes templated by the immature Gag lattice both in the absence of ESCRT-II and when multiple copies of ESCRT-II are localized at the bud neck. The ESCRT-I/II supercomplexes formed in our simulations exhibit predominantly columnar structures, which has important implications for the nucleation pathway of downstream ESCRT-III polymers. Importantly, ESCRT-I/II supercomplexes bound to Gag initiate membrane neck constriction by pulling the inner edge of the bud neck closer to the ESCRT-I headpiece ring. Our findings serve to elucidate a network of interactions between upstream ESCRT machinery, immature Gag lattice, and membrane neck that regulate protein assembly dynamics at the HIV-1 budding site.
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Affiliation(s)
- Arpa Hudait
- Department of Chemistry, Chicago Center for Theoretical Chemistry, Institute for Biophysical Dynamics, and James Franck Institute, The University of Chicago, Chicago, Illinois
| | - James H Hurley
- Department of Molecular and Cell Biology and California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, California; California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, California
| | - Gregory A Voth
- Department of Chemistry, Chicago Center for Theoretical Chemistry, Institute for Biophysical Dynamics, and James Franck Institute, The University of Chicago, Chicago, Illinois.
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8
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York SB, Hurwitz SN, Liu X, Meckes DG. Ceramide-dependent trafficking of Epstein-Barr virus LMP1 to small extracellular vesicles. Virology 2023; 581:128-138. [PMID: 36958217 DOI: 10.1016/j.virol.2023.02.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 02/14/2023] [Accepted: 02/21/2023] [Indexed: 03/11/2023]
Abstract
Epstein-Barr virus (EBV) is a human herpesvirus that is associated with a multitude of cancers. The primary EBV oncogene latent membrane protein 1 (LMP1) is secreted from infected cancer cells in small extracellular vesicles (EVs). Additionally, the tetraspanin protein CD63 forms a complex with LMP1 and CD63 can be trafficked to EVs through a ceramide-dependent manner. Therefore, we hypothesize that ceramide is required for efficient packaging of LMP1 into small EVs. Following treatment with the neutral sphingomyelinase inhibitor GW4869, LMP1 cellular localization was disrupted and immunoblotting of EV lysates revealed a significant reduction in extracellular LMP1. NTA of EVs from the LCLs treated with GW4869 demonstrated a significant decrease in particle secretion. Additionally, ceramide inhibition resulted in enhanced LMP1-mediated NFkB activation in EV producing cells. Taken together, these data reveal a critical role for the lipid ceramide in LMP1 exosomal trafficking and the oncogenic signaling properties of the viral protein.
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Affiliation(s)
- Sara B York
- Florida State University College of Medicine, Department of Biomedical Sciences, Tallahassee, FL, 32306, USA.
| | - Stephanie N Hurwitz
- Florida State University College of Medicine, Department of Biomedical Sciences, Tallahassee, FL, 32306, USA
| | - Xia Liu
- Florida State University College of Medicine, Department of Biomedical Sciences, Tallahassee, FL, 32306, USA
| | - David G Meckes
- Florida State University College of Medicine, Department of Biomedical Sciences, Tallahassee, FL, 32306, USA
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Whitehead M, Yusoff S, Ahmad S, Schmidt L, Mayr M, Madine J, Middleton D, Shanahan CM. Vascular smooth muscle cell senescence accelerates medin aggregation via small extracellular vesicle secretion and extracellular matrix reorganization. Aging Cell 2023; 22:e13746. [PMID: 36433666 PMCID: PMC9924949 DOI: 10.1111/acel.13746] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 11/07/2022] [Accepted: 11/13/2022] [Indexed: 11/27/2022] Open
Abstract
Vascular amyloidosis, caused when peptide monomers aggregate into insoluble amyloid, is a prevalent age-associated pathology. Aortic medial amyloid (AMA) is the most common human amyloid and is composed of medin, a 50-amino acid peptide. Emerging evidence has implicated extracellular vesicles (EVs) as mediators of pathological amyloid accumulation in the extracellular matrix (ECM). To determine the mechanisms of AMA formation with age, we explored the impact of vascular smooth muscle cell (VSMC) senescence, EV secretion, and ECM remodeling on medin accumulation. Medin was detected in EVs secreted from primary VSMCs. Small, round medin aggregates colocalized with EV markers in decellularized ECM in vitro and medin was shown on the surface of EVs deposited in the ECM. Decreasing EV secretion with an inhibitor attenuated aggregation and deposition of medin in the ECM. Medin accumulation in the aortic wall of human subjects was strongly correlated with age and VSMC senescence increased EV secretion, increased EV medin loading and triggered deposition of fibril-like medin. Proteomic analysis showed VSMC senescence induced changes in EV cargo and ECM composition, which led to enhanced EV-ECM binding and accelerated medin aggregation. Abundance of the proteoglycan, HSPG2, was increased in the senescent ECM and colocalized with EVs and medin. Isolated EVs selectively bound to HSPG2 in the ECM and its knock-down decreased formation of fibril-like medin structures. These data identify VSMC-derived EVs and HSPG2 in the ECM as key mediators of medin accumulation, contributing to age-associated AMA development.
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Affiliation(s)
- Meredith Whitehead
- School of Cardiovascular and Metabolic Medicine & SciencesKing's College LondonLondonUK
| | - Syabira Yusoff
- School of Cardiovascular and Metabolic Medicine & SciencesKing's College LondonLondonUK
| | - Sadia Ahmad
- School of Cardiovascular and Metabolic Medicine & SciencesKing's College LondonLondonUK
| | - Lukas Schmidt
- School of Cardiovascular and Metabolic Medicine & SciencesKing's College LondonLondonUK
| | - Manuel Mayr
- School of Cardiovascular and Metabolic Medicine & SciencesKing's College LondonLondonUK
| | - Jillian Madine
- Institute of Systems, Molecular and Integrative BiologyUniversity of LiverpoolLondonUK
| | | | - Catherine M. Shanahan
- School of Cardiovascular and Metabolic Medicine & SciencesKing's College LondonLondonUK
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10
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Azad K, Guilligay D, Boscheron C, Maity S, De Franceschi N, Sulbaran G, Effantin G, Wang H, Kleman JP, Bassereau P, Schoehn G, Roos WH, Desfosses A, Weissenhorn W. Structural basis of CHMP2A-CHMP3 ESCRT-III polymer assembly and membrane cleavage. Nat Struct Mol Biol 2023; 30:81-90. [PMID: 36604498 DOI: 10.1038/s41594-022-00867-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 10/12/2022] [Indexed: 01/07/2023]
Abstract
The endosomal sorting complex required for transport (ESCRT) is a highly conserved protein machinery that drives a divers set of physiological and pathological membrane remodeling processes. However, the structural basis of ESCRT-III polymers stabilizing, constricting and cleaving negatively curved membranes is yet unknown. Here we present cryo-EM structures of membrane-coated CHMP2A-CHMP3 filaments from Homo sapiens of two different diameters at 3.3 and 3.6 Å resolution. The structures reveal helical filaments assembled by CHMP2A-CHMP3 heterodimers in the open ESCRT-III conformation, which generates a partially positive charged membrane interaction surface, positions short N-terminal motifs for membrane interaction and the C-terminal VPS4 target sequence toward the tube interior. Inter-filament interactions are electrostatic, which may facilitate filament sliding upon VPS4-mediated polymer remodeling. Fluorescence microscopy as well as high-speed atomic force microscopy imaging corroborate that VPS4 can constrict and cleave CHMP2A-CHMP3 membrane tubes. We therefore conclude that CHMP2A-CHMP3-VPS4 act as a minimal membrane fission machinery.
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Affiliation(s)
- Kimi Azad
- Institute of Structural Biology (IBS), University Grenoble Alpes, CEA, CNRS, Grenoble, France
| | - Delphine Guilligay
- Institute of Structural Biology (IBS), University Grenoble Alpes, CEA, CNRS, Grenoble, France
| | - Cecile Boscheron
- Institute of Structural Biology (IBS), University Grenoble Alpes, CEA, CNRS, Grenoble, France
| | - Sourav Maity
- Moleculaire Biofysica, Zernike Institute, Rijksuniversiteit Groningen, Groningen, the Netherlands
| | - Nicola De Franceschi
- Institute of Structural Biology (IBS), University Grenoble Alpes, CEA, CNRS, Grenoble, France.,Curie Institute, Laboratory of Physical Chemistry Curie, University of PSL, Sorbonne University, CNRS, Paris, France
| | - Guidenn Sulbaran
- Institute of Structural Biology (IBS), University Grenoble Alpes, CEA, CNRS, Grenoble, France
| | - Gregory Effantin
- Institute of Structural Biology (IBS), University Grenoble Alpes, CEA, CNRS, Grenoble, France
| | - Haiyan Wang
- Institute of Structural Biology (IBS), University Grenoble Alpes, CEA, CNRS, Grenoble, France
| | - Jean-Philippe Kleman
- Institute of Structural Biology (IBS), University Grenoble Alpes, CEA, CNRS, Grenoble, France
| | - Patricia Bassereau
- Curie Institute, Laboratory of Physical Chemistry Curie, University of PSL, Sorbonne University, CNRS, Paris, France
| | - Guy Schoehn
- Institute of Structural Biology (IBS), University Grenoble Alpes, CEA, CNRS, Grenoble, France
| | - Wouter H Roos
- Moleculaire Biofysica, Zernike Institute, Rijksuniversiteit Groningen, Groningen, the Netherlands
| | - Ambroise Desfosses
- Institute of Structural Biology (IBS), University Grenoble Alpes, CEA, CNRS, Grenoble, France.
| | - Winfried Weissenhorn
- Institute of Structural Biology (IBS), University Grenoble Alpes, CEA, CNRS, Grenoble, France.
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11
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Avalos-Padilla Y, Georgiev VN, Ewins E, Robinson T, Orozco E, Lipowsky R, Dimova R. Stepwise remodeling and subcompartment formation in individual vesicles by three ESCRT-III proteins. iScience 2022; 26:105765. [PMID: 36590172 PMCID: PMC9800321 DOI: 10.1016/j.isci.2022.105765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 10/21/2022] [Accepted: 12/06/2022] [Indexed: 12/13/2022] Open
Abstract
The endosomal sorting complex required for transport (ESCRT) is a multi-protein machinery involved in several membrane remodeling processes. Different approaches have been used to resolve how ESCRT proteins scission membranes. However, the underlying mechanisms generating membrane deformations are still a matter of debate. Here, giant unilamellar vesicles, microfluidic technology, and micropipette aspiration are combined to continuously follow the ESCRT-III-mediated membrane remodeling on the single-vesicle level for the first time. With this approach, we identify different mechanisms by which a minimal set of three ESCRT-III proteins from Entamoeba histolytica reshape the membrane. These proteins modulate the membrane stiffness and spontaneous curvature to regulate bud size and generate intraluminal vesicles even in the absence of ATP. We demonstrate that the bud stability depends on the protein concentration and membrane tension. The approaches introduced here should open the road to diverse applications in synthetic biology for establishing artificial cells with several membrane compartments.
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Affiliation(s)
- Yunuen Avalos-Padilla
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14476 Potsdam, Germany,Nanomalaria Group, Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Baldiri Reixac 10-12, ES-08028 Barcelona, Spain,Barcelona Institute for Global Health (ISGlobal, Hospital Clínic-Universitat de Barcelona), Rosselló 149-153, ES-08036 Barcelona, Spain
| | - Vasil N. Georgiev
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14476 Potsdam, Germany
| | - Eleanor Ewins
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14476 Potsdam, Germany
| | - Tom Robinson
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14476 Potsdam, Germany
| | - Esther Orozco
- Departamento de Infectómica y Patogénesis Molecular, CINVESTAV IPN, 07360 Ciudad de México, México
| | - Reinhard Lipowsky
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14476 Potsdam, Germany
| | - Rumiana Dimova
- Max Planck Institute of Colloids and Interfaces, Science Park Golm, 14476 Potsdam, Germany,Corresponding author
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12
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Bañuelos C, Betanzos A, Javier-Reyna R, Galindo A, Orozco E. Molecular interplays of the Entamoeba histolytica endosomal sorting complexes required for transport during phagocytosis. Front Cell Infect Microbiol 2022; 12:855797. [PMID: 36389174 PMCID: PMC9647190 DOI: 10.3389/fcimb.2022.855797] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Accepted: 10/06/2022] [Indexed: 08/23/2024] Open
Abstract
Entamoeba histolytica, the causative agent of human amoebiasis, exhibits a continuous membrane remodelling to exert its virulence properties. During this dynamic process, the Endosomal Sorting Complexes Required for Transport (ESCRT) machinery is a key player, particularly in phagocytosis, a virulence hallmark of this parasite. In addition to ESCRT, other molecules contribute to membrane remodelling, including the EhADH adhesin, EhRabs, actin, and the lysobisphosphatidic acid (LBPA). The endocytosis of a prey or molecules induces membrane invaginations, resulting in endosome and multivesicular bodies (MVBs) formation for cargo delivery into lysosomes. Alternatively, some proteins are recycled or secreted. Most of these pathways have been broadly characterized in other biological systems, but poorly described in protozoan parasites. Here, we encompass 10 years of ESCRT research in E. histolytica, highlighting the role of the ESCRT-I and ESCRT-III components and the EhADH and EhVps4-ATPase accessory proteins during phagocytosis. In particular, EhADH exhibits a multifunctional role along the endocytic pathway, from cargo recognition to endosome maturation and lysosomal degradation. Interestingly, the interaction of EhADH with EhVps32 seems to shape a concurrent route to the conventional one for MVBs biogenesis, that could optimize their formation. Furthermore, this adhesin is secreted, but its role in this event remains under study. Other components from the endosomal pathway, such as EhVps23 and LBPA, are also secreted. A proteomic approach performed here, using an anti-LBPA antibody, revealed that some proteins related to membrane trafficking, cellular transport, cytoskeleton dynamics, and transcriptional and translational functions are secreted and associated to LBPA. Altogether, the accumulated knowledge around the ESCRT machinery in E. histolytica, points it out as a dynamic platform facilitating the interaction of molecules participating in different cellular events. Seen as an integrated system, ESCRTs lead to a better understanding of E. histolytica phagocytosis.
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Affiliation(s)
- Cecilia Bañuelos
- Coordinación General de Programas de Posgrado Multidisciplinarios, Programa de Doctorado Transdisciplinario en Desarrollo Científico y Tecnológico para la Sociedad, Centro de Investigación y de Estudios Avanzados (CINVESTAV), Mexico City, Mexico
| | - Abigail Betanzos
- Investigadores por Mexico, Consejo Nacional de Ciencia y Tecnología (CONACYT), Mexico City, Mexico
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados (CINVESTAV), Mexico City, Mexico
| | - Rosario Javier-Reyna
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados (CINVESTAV), Mexico City, Mexico
| | - Ausencio Galindo
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados (CINVESTAV), Mexico City, Mexico
| | - Esther Orozco
- Departamento de Infectómica y Patogénesis Molecular, Centro de Investigación y de Estudios Avanzados (CINVESTAV), Mexico City, Mexico
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13
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Hatano T, Palani S, Papatziamou D, Salzer R, Souza DP, Tamarit D, Makwana M, Potter A, Haig A, Xu W, Townsend D, Rochester D, Bellini D, Hussain HMA, Ettema TJG, Löwe J, Baum B, Robinson NP, Balasubramanian M. Asgard archaea shed light on the evolutionary origins of the eukaryotic ubiquitin-ESCRT machinery. Nat Commun 2022; 13:3398. [PMID: 35697693 PMCID: PMC9192718 DOI: 10.1038/s41467-022-30656-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Accepted: 05/10/2022] [Indexed: 11/23/2022] Open
Abstract
The ESCRT machinery, comprising of multiple proteins and subcomplexes, is crucial for membrane remodelling in eukaryotic cells, in processes that include ubiquitin-mediated multivesicular body formation, membrane repair, cytokinetic abscission, and virus exit from host cells. This ESCRT system appears to have simpler, ancient origins, since many archaeal species possess homologues of ESCRT-III and Vps4, the components that execute the final membrane scission reaction, where they have been shown to play roles in cytokinesis, extracellular vesicle formation and viral egress. Remarkably, metagenome assemblies of Asgard archaea, the closest known living relatives of eukaryotes, were recently shown to encode homologues of the entire cascade involved in ubiquitin-mediated membrane remodelling, including ubiquitin itself, components of the ESCRT-I and ESCRT-II subcomplexes, and ESCRT-III and Vps4. Here, we explore the phylogeny, structure, and biochemistry of Asgard homologues of the ESCRT machinery and the associated ubiquitylation system. We provide evidence for the ESCRT-I and ESCRT-II subcomplexes being involved in ubiquitin-directed recruitment of ESCRT-III, as it is in eukaryotes. Taken together, our analyses suggest a pre-eukaryotic origin for the ubiquitin-coupled ESCRT system and a likely path of ESCRT evolution via a series of gene duplication and diversification events.
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Grants
- MC_U105184326 Medical Research Council
- MC_UP_1201/27 Medical Research Council
- 203276/Z/16/Z Wellcome Trust
- Wellcome Trust
- WT101885MA Wellcome Trust
- Wellcome Trust (Wellcome)
- Leverhulme Trust
- Svenska Forskningsrådet Formas (Swedish Research Council Formas)
- Above funding attributed to the authors as follows (from paper acknowledgements): Computational analysis was facilitated by resources provided by the Swedish National Infrastructure for Computing (SNIC) at the Uppsala Multidisciplinary Center for Advanced Computational Science (UPPMAX), partially funded by the Swedish Research Council through grant agreement no. 2018-05973. We thank the Warwick Proteomics RTP for mass spectrometry. MKB was supported by the Wellcome Trust (WT101885MA) and the European Research Council (ERC-2014-ADG No. 671083). Work by the NR laboratory was supported by start-up funds from the Division of Biomedical and Life Sciences (BLS, Lancaster University) and a Leverhulme Research Project Grant (RPG-2019-297). NR would like to thank Johanna Syrjanen for performing trial expressions of the Odinarchaeota ESCRT proteins, and Joseph Maman for helpful discussion regarding the SEC-MALS. NR, WX and AP would like to thank Charley Lai and Siu-Kei Yau for assistance with initial Odinarchaeota ESCRT protein purifications. DPS and BB would like to thank Chris Johnson at the MRC LMB Biophysics facility for performing the SEC-MALS assay on Heimdallarchaeotal Vps22. TH, HH, MB, RS, JL, D Tamarit, TE, DPS and BB received support from a Wellcome Trust collaborative award (203276/Z/16/Z). BB and DPS were supported by the MRC. D Tamarit was supported by the Swedish Research Council (International Postdoc grant 2018-06609).
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Affiliation(s)
- Tomoyuki Hatano
- Centre for Mechanochemical Cell Biology, Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, CV4 7AL, UK
| | - Saravanan Palani
- Centre for Mechanochemical Cell Biology, Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, CV4 7AL, UK
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Dimitra Papatziamou
- Division of Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster, LA1 4YG, UK
| | - Ralf Salzer
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK
| | - Diorge P Souza
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK
| | - Daniel Tamarit
- Laboratory of Microbiology, Wageningen University, 6708 WE, Wageningen, The Netherlands
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, SE-75007, Uppsala, Sweden
| | - Mehul Makwana
- Division of Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster, LA1 4YG, UK
| | - Antonia Potter
- Division of Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster, LA1 4YG, UK
| | - Alexandra Haig
- Division of Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster, LA1 4YG, UK
| | - Wenjue Xu
- Division of Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster, LA1 4YG, UK
| | - David Townsend
- Department of Chemistry, Lancaster University, Lancaster, LA1 4YB, UK
| | - David Rochester
- Department of Chemistry, Lancaster University, Lancaster, LA1 4YB, UK
| | - Dom Bellini
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK
| | - Hamdi M A Hussain
- Centre for Mechanochemical Cell Biology, Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, CV4 7AL, UK
| | - Thijs J G Ettema
- Laboratory of Microbiology, Wageningen University, 6708 WE, Wageningen, The Netherlands
| | - Jan Löwe
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK
| | - Buzz Baum
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK.
| | - Nicholas P Robinson
- Division of Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancaster, LA1 4YG, UK.
| | - Mohan Balasubramanian
- Centre for Mechanochemical Cell Biology, Division of Biomedical Sciences, Warwick Medical School, University of Warwick, Coventry, CV4 7AL, UK.
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14
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Morris‐Love J, O'Hara BA, Gee GV, Dugan AS, O'Rourke RS, Armstead BE, Assetta B, Haley SA, Atwood WJ. Biogenesis of JC polyomavirus associated extracellular vesicles. JOURNAL OF EXTRACELLULAR BIOLOGY 2022; 1:e43. [PMID: 36688929 PMCID: PMC9854252 DOI: 10.1002/jex2.43] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 04/09/2022] [Accepted: 04/13/2022] [Indexed: 01/26/2023]
Abstract
JC polyomavirus (JCPyV) is a small, non-enveloped virus that persists in the kidney in about half the adult population. In severely immune-compromised individuals JCPyV causes the neurodegenerative disease progressive multifocal leukoencephalopathy (PML) in the brain. JCPyV has been shown to infect cells by both direct and indirect mechanisms, the latter involving extracellular vesicle (EV) mediated infection. While direct mechanisms of infection are well studied indirect EV mediated mechanisms are poorly understood. Using a combination of chemical and genetic approaches we show that several overlapping intracellular pathways are responsible for the biogenesis of virus containing EV. Here we show that targeting neutral sphingomyelinase 2 (nSMase2) with the drug cambinol decreased the spread of JCPyV over several viral life cycles. Genetic depletion of nSMase2 by either shRNA or CRISPR/Cas9 reduced EV-mediated infection. Individual knockdown of seven ESCRT-related proteins including HGS, ALIX, TSG101, VPS25, VPS20, CHMP4A, and VPS4A did not significantly reduce JCPyV associated EV (JCPyV(+) EV) infectivity, whereas knockdown of the tetraspanins CD9 and CD81 or trafficking and/or secretory autophagy-related proteins RAB8A, RAB27A, and GRASP65 all significantly reduced the spread of JCPyV and decreased EV-mediated infection. These findings point to a role for exosomes and secretory autophagosomes in the biogenesis of JCPyV associated EVs with specific roles for nSMase2, CD9, CD81, RAB8A, RAB27A, and GRASP65 proteins.
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Affiliation(s)
- Jenna Morris‐Love
- Graduate Program in PathobiologyBrown UniversityProvidenceRIUSA
- Department of Molecular biologyCellular Biologyand BiochemistryBrown UniversityProvidenceRIUSA
| | - Bethany A. O'Hara
- Department of Molecular biologyCellular Biologyand BiochemistryBrown UniversityProvidenceRIUSA
| | - Gretchen V. Gee
- Department of Molecular biologyCellular Biologyand BiochemistryBrown UniversityProvidenceRIUSA
- MassBiologicsUniversity of Massachusetts Medical SchoolFall RiverMAUSA
| | - Aisling S. Dugan
- Department of BiologyAssumption UniversityWorcesterMAUSA
- Department of Molecular Microbiology and ImmunologyBrown UniversityProvidenceRIUSA
| | - Ryan S. O'Rourke
- Graduate Program in PathobiologyBrown UniversityProvidenceRIUSA
- Department of Molecular biologyCellular Biologyand BiochemistryBrown UniversityProvidenceRIUSA
| | | | - Benedetta Assetta
- Department of Molecular biologyCellular Biologyand BiochemistryBrown UniversityProvidenceRIUSA
| | - Sheila A. Haley
- Department of Molecular biologyCellular Biologyand BiochemistryBrown UniversityProvidenceRIUSA
| | - Walter J. Atwood
- Department of Molecular biologyCellular Biologyand BiochemistryBrown UniversityProvidenceRIUSA
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15
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Wang BZ, Luo L, Vunjak-Novakovic G. RNA and Protein Delivery by Cell-Secreted and Bioengineered Extracellular Vesicles. Adv Healthc Mater 2022; 11:e2101557. [PMID: 34706168 PMCID: PMC8891029 DOI: 10.1002/adhm.202101557] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 09/28/2021] [Indexed: 12/22/2022]
Abstract
Extracellular vesicles (EVs) are carriers of biological signals through export and delivery of RNAs and proteins. Of increasing interest is the use of EVs as a platform for delivery of biomolecules. Preclinical studies have effectively used EVs to treat a number of diseases. Uniquely, endogenous machinery within cells can be manipulated in order to produce desirable loading of cargo within secreted EVs. In order to inform the development of such approaches, an understanding of the cellular mechanisms by which cargo is sorted to EVs is required. Here, the current knowledge of cargo sorting within EVs is reviewed. Here is given an overview of recent bioengineering approaches that leverage these advances. Methods of externally manipulating EV cargo are also discussed. Finally, a perspective on the current challenges of EVs as a drug delivery platform is offered. It is proposed that standardized bioengineering methods for therapeutic EV preparation will be required to create a well-defined clinical product.
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Affiliation(s)
- Bryan Z. Wang
- Department of Biomedical Engineering, 622 West 168th Street VC12-234, 10032, U.S.A
- Department of Medicine, 622 West 168th Street VC12-234, 10032, U.S.A
| | - Lori Luo
- Department of Medicine, 622 West 168th Street VC12-234, 10032, U.S.A
| | - Gordana Vunjak-Novakovic
- Department of Biomedical Engineering, 622 West 168th Street VC12-234, 10032, U.S.A
- Department of Medicine, 622 West 168th Street VC12-234, 10032, U.S.A
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16
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Georgiev V, Avalos-Padilla Y, Fernàndez-Busquets X, Dimova R. Femtoliter Injection of ESCRT-III Proteins into Adhered Giant Unilamellar Vesicles. Bio Protoc 2022; 12:e4328. [DOI: 10.21769/bioprotoc.4328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 11/12/2021] [Accepted: 01/06/2022] [Indexed: 11/02/2022] Open
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17
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ESCRT-III induces phase separation in model membranes prior to budding and causes invagination of the liquid-ordered phase. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2021; 1863:183689. [PMID: 34224704 DOI: 10.1016/j.bbamem.2021.183689] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 06/05/2021] [Accepted: 06/27/2021] [Indexed: 11/21/2022]
Abstract
Membrane fission triggered by the endosomal sorting complex required for transport (ESCRT) is an important process observed in several pathogenic and non-pathogenic cellular events. From a synthetic-biology viewpoint, ESCRT proteins represent an interesting machinery for the construction of cell mimetic sub-compartments produced by fission. Since their discovery, the studies on ESCRT-III-mediated action, have mainly focused on protein dynamics, ignoring the role of lipid organization and membrane phase state. Recently, it has been suggested that membrane buds formed by the action of ESCRT-III are generated from transient microdomains in endosomal membranes. However, the interplay between membrane domain formation and ESCRT remodeling pathways has not been investigated. Here, giant unilamellar vesicles made of ternary lipid mixtures, either homogeneous in phase or exhibiting liquid-ordered/liquid-disordered phase coexistence, were employed as a model membrane system. These vesicles were incubated with purified recombinant ESCRT-III proteins from the parasite Entamoeba histolytica. In homogeneous membranes, we observe that EhVps32 can trigger domain formation while EhVps20 preferentially co-localizes in the liquid disordered phase. The addition of EhVps24 appears to induce the formation of intraluminal vesicles produced from the liquid-ordered phase. In phase separated membranes, the intraluminal vesicles are also generated from the liquid-ordered phase and presumably emerge from the phase boundary region. Our findings reinforce the hypothesis that ESCRT-mediated remodeling depends on the membrane phase state. Furthermore, the obtained results point to a potential synthetic biology approach for establishing eukaryotic mimics of artificial cells with microcompartments of specific membrane composition, which can also differ from that of the mother vesicle.
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18
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Mandal T, Spagnolie SE, Audhya A, Cui Q. Protein-induced membrane curvature in coarse-grained simulations. Biophys J 2021; 120:3211-3221. [PMID: 34197798 DOI: 10.1016/j.bpj.2021.05.029] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 05/06/2021] [Accepted: 05/28/2021] [Indexed: 12/01/2022] Open
Abstract
Using the endosomal sorting complex required for transport (ESCRT)-III membrane remodeling complex as an example, we analyze three popular coarse-grained models (the regular MARTINI, polarizable MARTINI (POL-MARTINI), and big multipole water MARTINI (BMW-MARTINI)) for the description of membrane curvature sensing and generation activities of peripheral proteins. Although the three variants of the MARTINI model provide consistent descriptions for the protein-protein interface in a linear filament model of ESCRT-III, they differ considerably in terms of protein-membrane interface and therefore membrane curvature sensing and generation behaviors. In particular, BMW-MARTINI provides the most consistent description of the protein-membrane interface as compared to all-atom simulations, whereas the regular MARTINI is most consistent with atomistic simulations in terms of the qualitative sign of membrane curvature sensing and generation. With POL-MARTINI, the ESCRT-III model interacts weakly with the membrane and therefore does not exhibit any curvature-sensitive activities. Analysis suggests that the incorrect membrane curvature activities predicted by BMW-MARTINI are due to overestimated insertion depth of an amphipathic helix and incorrect sign for the spontaneous curvature of anionic lipids. These results not only point to ways that coarse-grained models can be improved but also explicitly highlight local lipid composition and insertion depth of protein motifs as essential regulatory factors for membrane curvature sensing and generation.
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Affiliation(s)
- Taraknath Mandal
- Department of Chemistry, Boston University, Boston, Massachusetts; Department of Physics, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Saverio E Spagnolie
- Department of Mathematics, University of Wisconsin-Madison, Madison, Wisconsin
| | - Anjon Audhya
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, Wisconsin
| | - Qiang Cui
- Departments of Chemistry, Physics, and Biomedical Engineering, Boston University, Boston, Massachusetts.
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19
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Avalos-Padilla Y, Georgiev VN, Lantero E, Pujals S, Verhoef R, N. Borgheti-Cardoso L, Albertazzi L, Dimova R, Fernàndez-Busquets X. The ESCRT-III machinery participates in the production of extracellular vesicles and protein export during Plasmodium falciparum infection. PLoS Pathog 2021; 17:e1009455. [PMID: 33798247 PMCID: PMC9159051 DOI: 10.1371/journal.ppat.1009455] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 04/14/2021] [Accepted: 03/08/2021] [Indexed: 01/08/2023] Open
Abstract
Infection with Plasmodium falciparum enhances extracellular
vesicle (EV) production in parasitized red blood cells (pRBCs), an important
mechanism for parasite-to-parasite communication during the asexual
intraerythrocytic life cycle. The endosomal
sorting complex
required for transport
(ESCRT), and in particular the ESCRT-III sub-complex, participates in the
formation of EVs in higher eukaryotes. However, RBCs have lost the majority of
their organelles through the maturation process, including an important
reduction in their vesicular network. Therefore, the mechanism of EV production
in P. falciparum-infected RBCs remains to be
elucidated. Here we demonstrate that P.
falciparum possesses a functional ESCRT-III machinery
activated by an alternative recruitment pathway involving the action of PfBro1
and PfVps32/PfVps60 proteins. Additionally, multivesicular body formation and
membrane shedding, both reported mechanisms of EV production, were reconstituted
in the membrane model of giant unilamellar vesicles using the purified
recombinant proteins. Moreover, the presence of PfVps32, PfVps60 and PfBro1 in
EVs purified from a pRBC culture was confirmed by super-resolution microscopy
and dot blot assays. Finally, disruption of the PfVps60 gene
led to a reduction in the number of the produced EVs in the KO strain and
affected the distribution of other ESCRT-III components. Overall, our results
increase the knowledge on the underlying molecular mechanisms during malaria
pathogenesis and demonstrate that ESCRT-III P.
falciparum proteins participate in EV production. Malaria is a disease caused by Plasmodium parasites that is
still a leading cause of death in many low-income countries, and for which
currently available therapeutic strategies are not succeeding in its control,
let alone eradication. An interesting feature observed after
Plasmodium invasion is the increase of extracellular
vesicles (EVs) generated by parasitized red blood cells (pRBCs), which lack a
vesicular trafficking that would explain EV production. Here, by combining
different approaches, we demonstrated the participation of the
endosomal sorting
complex required for
transport (ESCRT) machinery from Plasmodium
falciparum in the production of EVs in pRBCs. Moreover, we were
able to detect ESCRT-III proteins adjacent to the membrane of the host and in
EVs purified from a pRBC culture, which shows the export of these proteins and
their participation in EV production. Finally, the disruption of an ESCRT-III
associated gene, Pfvps60, led to a significant reduction in the
amount of EVs. Altogether, these results confirm ESCRT-III participation in EV
production and provide novel information on the P.
falciparum protein export mechanisms, which can be used for
the development of new therapeutic strategies against malaria, based on the
disruption of EV formation and trafficking.
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Affiliation(s)
- Yunuen Avalos-Padilla
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute
of Science and Technology (BIST), Barcelona, Spain
- Barcelona Institute for Global Health (ISGlobal, Hospital
Clínic-Universitat de Barcelona), Barcelona, Spain
- Department of Theory and Bio-Systems, Max Planck Institute of Colloids
and Interfaces, Science Park Golm, Potsdam, Germany
- * E-mail: (YA-P); (XF-B)
| | - Vasil N. Georgiev
- Department of Theory and Bio-Systems, Max Planck Institute of Colloids
and Interfaces, Science Park Golm, Potsdam, Germany
| | - Elena Lantero
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute
of Science and Technology (BIST), Barcelona, Spain
- Barcelona Institute for Global Health (ISGlobal, Hospital
Clínic-Universitat de Barcelona), Barcelona, Spain
| | - Silvia Pujals
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute
of Science and Technology (BIST), Barcelona, Spain
- Department of Electronics and Biomedical Engineering, Faculty of Physics,
Universitat de Barcelona, Barcelona, Spain
| | - René Verhoef
- Computational Biology Group, Eindhoven University of Technology,
Eindhoven, The Netherlands
| | - Livia N. Borgheti-Cardoso
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute
of Science and Technology (BIST), Barcelona, Spain
| | - Lorenzo Albertazzi
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute
of Science and Technology (BIST), Barcelona, Spain
- Department of Biomedical Engineering and the Institute for Complex
Molecular Systems, Eindhoven University of Technology, Eindhoven, The
Netherlands
| | - Rumiana Dimova
- Department of Theory and Bio-Systems, Max Planck Institute of Colloids
and Interfaces, Science Park Golm, Potsdam, Germany
| | - Xavier Fernàndez-Busquets
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute
of Science and Technology (BIST), Barcelona, Spain
- Barcelona Institute for Global Health (ISGlobal, Hospital
Clínic-Universitat de Barcelona), Barcelona, Spain
- * E-mail: (YA-P); (XF-B)
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20
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Meusser B, Purfuerst B, Luft FC. HIV-1 Gag release from yeast reveals ESCRT interaction with the Gag N-terminal protein region. J Biol Chem 2020; 295:17950-17972. [PMID: 32994219 PMCID: PMC7939435 DOI: 10.1074/jbc.ra120.014710] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 09/25/2020] [Indexed: 11/30/2022] Open
Abstract
The HIV-1 protein Gag assembles at the plasma membrane and drives virion budding, assisted by the cellular endosomal complex required for transport (ESCRT) proteins. Two ESCRT proteins, TSG101 and ALIX, bind to the Gag C-terminal p6 peptide. TSG101 binding is important for efficient HIV-1 release, but how ESCRTs contribute to the budding process and how their activity is coordinated with Gag assembly is poorly understood. Yeast, allowing genetic manipulation that is not easily available in human cells, has been used to characterize the cellular ESCRT function. Previous work reported Gag budding from yeast spheroplasts, but Gag release was ESCRT-independent. We developed a yeast model for ESCRT-dependent Gag release. We combined yeast genetics and Gag mutational analysis with Gag-ESCRT binding studies and the characterization of Gag-plasma membrane binding and Gag release. With our system, we identified a previously unknown interaction between ESCRT proteins and the Gag N-terminal protein region. Mutations in the Gag-plasma membrane-binding matrix domain that reduced Gag-ESCRT binding increased Gag-plasma membrane binding and Gag release. ESCRT knockout mutants showed that the release enhancement was an ESCRT-dependent effect. Similarly, matrix mutation enhanced Gag release from human HEK293 cells. Release enhancement partly depended on ALIX binding to p6, although binding site mutation did not impair WT Gag release. Accordingly, the relative affinity for matrix compared with p6 in GST-pulldown experiments was higher for ALIX than for TSG101. We suggest that a transient matrix-ESCRT interaction is replaced when Gag binds to the plasma membrane. This step may activate ESCRT proteins and thereby coordinate ESCRT function with virion assembly.
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Affiliation(s)
- Birgit Meusser
- Charité Medical Faculty, Berlin, Germany; Max-Delbrück-Center for Molecular Medicine, Berlin, Germany
| | | | - Friedrich C Luft
- Charité Medical Faculty, Berlin, Germany; Max-Delbrück-Center for Molecular Medicine, Berlin, Germany; Experimental and Clinical Research Center, Berlin, Germany.
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21
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Koul S, Schaal VL, Chand S, Pittenger ST, Nanoth Vellichirammal N, Kumar V, Guda C, Bevins RA, Yelamanchili SV, Pendyala G. Role of Brain Derived Extracellular Vesicles in Decoding Sex Differences Associated with Nicotine Self-Administration. Cells 2020; 9:cells9081883. [PMID: 32796722 PMCID: PMC7464419 DOI: 10.3390/cells9081883] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2020] [Revised: 08/04/2020] [Accepted: 08/06/2020] [Indexed: 02/06/2023] Open
Abstract
Smoking remains a significant health and economic concern in the United States. Furthermore, the emerging pattern of nicotine intake between sexes further adds a layer of complexity. Nicotine is a potent psychostimulant with a high addiction liability that can significantly alter brain function. However, the neurobiological mechanisms underlying nicotine’s impact on brain function and behavior remain unclear. Elucidation of these mechanisms is of high clinical importance and may lead to improved therapeutics for smoking cessation. To fill in this critical knowledge gap, our current study focused on identifying sex-specific brain-derived extracellular vesicles (BDEV) signatures in male and female rats post nicotine self-administration. Extracellular vesicles (EVs) are comprised of phospholipid nanovesicles such as apoptotic bodies, microvesicles (MVs), and exosomes based on their origin or size. EVs are garnering significant attention as molecules involved in cell–cell communication and thus regulating the pathophysiology of several diseases. Interestingly, females post nicotine self-administration, showed larger BDEV sizes, along with impaired EV biogenesis compared to males. Next, using quantitative mass spectrometry-based proteomics, we identified BDEV signatures, including distinct molecular pathways, impacted between males and females. In summary, this study has identified sex-specific changes in BDEV biogenesis, protein cargo signatures, and molecular pathways associated with long-term nicotine self-administration.
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Affiliation(s)
- Sneh Koul
- Department of Anesthesiology, University of Nebraska Medical Center, Omaha, NE 68198, USA; (S.K.); (V.L.S.); (S.C.); (S.V.Y.)
| | - Victoria L. Schaal
- Department of Anesthesiology, University of Nebraska Medical Center, Omaha, NE 68198, USA; (S.K.); (V.L.S.); (S.C.); (S.V.Y.)
| | - Subhash Chand
- Department of Anesthesiology, University of Nebraska Medical Center, Omaha, NE 68198, USA; (S.K.); (V.L.S.); (S.C.); (S.V.Y.)
| | - Steven T. Pittenger
- Department of Psychology, University of Nebraska-Lincoln, Lincoln, NE 68588, USA; (S.T.P.); (R.A.B.)
| | - Neetha Nanoth Vellichirammal
- Department of Genetics Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE 68198, USA; (N.N.V.); (C.G.)
| | - Vikas Kumar
- Mass Spectrometry and Proteomics Core Facility, University of Nebraska Medical Center, Omaha, NE 68198, USA;
| | - Chittibabu Guda
- Department of Genetics Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE 68198, USA; (N.N.V.); (C.G.)
| | - Rick A. Bevins
- Department of Psychology, University of Nebraska-Lincoln, Lincoln, NE 68588, USA; (S.T.P.); (R.A.B.)
| | - Sowmya V. Yelamanchili
- Department of Anesthesiology, University of Nebraska Medical Center, Omaha, NE 68198, USA; (S.K.); (V.L.S.); (S.C.); (S.V.Y.)
| | - Gurudutt Pendyala
- Department of Anesthesiology, University of Nebraska Medical Center, Omaha, NE 68198, USA; (S.K.); (V.L.S.); (S.C.); (S.V.Y.)
- Correspondence: ; Tel.: +1-402-559-8690
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22
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Rosen E, Fatanmi OO, Wise SY, Rao VA, Singh VK. Tocol Prophylaxis for Total-body Irradiation: A Proteomic Analysis in Murine Model. HEALTH PHYSICS 2020; 119:12-20. [PMID: 32205715 DOI: 10.1097/hp.0000000000001221] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The aim of this study was to analyze the changes in mouse jejunum protein expression in response to prophylactic administration of two promising tocols, γ-tocotrienol (GT3) and α-tocopherol succinate (TS), as radiation countermeasures before irradiation to elucidate the molecular mechanism(s) of their radioprotective efficacy. Mice were administered GT3 or TS (200 mg kg) subcutaneously 24 h prior to exposure to 11 Gy Co γ-radiation, a supralethal dose for mice. Jejunum was harvested 24 h post-irradiation. Results of the two-dimensional differential in-gel electrophoresis (2D-DIGE), coupled with mass spectrometry, and advanced bioinformatics tools suggest that the tocols have a corresponding impact on expression of 13 proteins as identified by mass spectrometry. Ingenuity Pathway Analysis (IPA) reveals a network of associated proteins involved in inflammatory response, organismal injury and abnormalities, and cellular development. Relevant signaling pathways including actin cytoskeleton signaling, RhoA signaling, and Rho family GTPase were identified. This study reveals the major proteins, pathways, and networks involved in preventing the radiation-induced injury in gut that may be contributing to enhanced survival.
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Affiliation(s)
- Elliot Rosen
- Division of Biotechnology Research and Review III, Office of Biotechnology Products, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, MD
| | | | | | - V Ashutosh Rao
- Division of Biotechnology Research and Review III, Office of Biotechnology Products, Center for Drug Evaluation and Research, U.S. Food and Drug Administration, Silver Spring, MD
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23
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von Appen A, LaJoie D, Johnson IE, Trnka MJ, Pick SM, Burlingame AL, Ullman KS, Frost A. LEM2 phase separation promotes ESCRT-mediated nuclear envelope reformation. Nature 2020; 582:115-118. [PMID: 32494070 PMCID: PMC7321842 DOI: 10.1038/s41586-020-2232-x] [Citation(s) in RCA: 84] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 02/26/2020] [Indexed: 01/01/2023]
Abstract
During cell division, remodelling of the nuclear envelope enables chromosome segregation by the mitotic spindle1. The reformation of sealed nuclei requires ESCRTs (endosomal sorting complexes required for transport) and LEM2, a transmembrane ESCRT adaptor2-4. Here we show how the ability of LEM2 to condense on microtubules governs the activation of ESCRTs and coordinated spindle disassembly. The LEM motif of LEM2 binds BAF, conferring on LEM2 an affinity for chromatin5,6, while an adjacent low-complexity domain (LCD) promotes LEM2 phase separation. A proline-arginine-rich sequence within the LCD binds to microtubules and targets condensation of LEM2 to spindle microtubules that traverse the nascent nuclear envelope. Furthermore, the winged-helix domain of LEM2 activates the ESCRT-II/ESCRT-III hybrid protein CHMP7 to form co-oligomeric rings. Disruption of these events in human cells prevented the recruitment of downstream ESCRTs, compromised spindle disassembly, and led to defects in nuclear integrity and DNA damage. We propose that during nuclear reassembly LEM2 condenses into a liquid-like phase and coassembles with CHMP7 to form a macromolecular O-ring seal at the confluence between membranes, chromatin and the spindle. The properties of LEM2 described here, and the homologous architectures of related inner nuclear membrane proteins7,8, suggest that phase separation may contribute to other critical envelope functions, including interphase repair8-13 and chromatin organization14-17.
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Affiliation(s)
- Alexander von Appen
- Department of Biochemistry and Biophysics, University of California, San Francisco, CA, USA
| | - Dollie LaJoie
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, UT, USA
| | - Isabel E Johnson
- Department of Biochemistry and Biophysics, University of California, San Francisco, CA, USA
| | - Michael J Trnka
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA, USA
| | - Sarah M Pick
- Faculty of Chemistry and Pharmacy, University of Freiburg, Freiburg, Germany
| | - Alma L Burlingame
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA, USA
| | - Katharine S Ullman
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, UT, USA.
| | - Adam Frost
- Department of Biochemistry and Biophysics, University of California, San Francisco, CA, USA.
- Chan Zuckerberg Biohub, San Francisco, CA, USA.
- Quantitative Biosciences Institute, University of California, San Francisco, San Francisco, CA, USA.
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24
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Mandal T, Lough W, Spagnolie SE, Audhya A, Cui Q. Molecular Simulation of Mechanical Properties and Membrane Activities of the ESCRT-III Complexes. Biophys J 2020; 118:1333-1343. [PMID: 32078797 PMCID: PMC7091516 DOI: 10.1016/j.bpj.2020.01.033] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 01/26/2020] [Accepted: 01/29/2020] [Indexed: 01/16/2023] Open
Abstract
The endosomal sorting complex required for transport (ESCRT) machinery carries out the membrane scission reactions that are required for many biological processes throughout cells. How ESCRTs bind and deform cellular membranes and ultimately produce vesicles has been a matter of active research in recent years. In this study, we use fully atomistic molecular dynamics simulations to scrutinize the structural details of a filament composed of Vps32 protomers, a major component of ESCRT-III complexes. The simulations show that both hydrophobic and electrostatic interactions between monomers help maintain the structural stability of the filament, which exhibits an intrinsic bend and twist. Our findings suggest that the accumulation of bending and twisting stresses as the filament elongates on the membrane surface likely contributes to the driving force for membrane invagination. The filament exposes a large cationic surface that senses the negatively charged lipids in the membrane, and the N-terminal amphipathic helix of the monomers not only acts as a membrane anchor but also generates significant positive membrane curvature. Taking all results together, we discuss a plausible mechanism for membrane invagination driven by ESCRT-III.
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Affiliation(s)
- Taraknath Mandal
- Department of Chemistry, Boston University, Boston, Massachusetts
| | | | | | - Anjon Audhya
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, Wisconsin
| | - Qiang Cui
- Departments of Chemistry, Physics, and Biomedical Engineering, Boston University, Boston, Massachusetts.
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25
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Booth A, Marklew CJ, Ciani B, Beales PA. In Vitro Membrane Remodeling by ESCRT is Regulated by Negative Feedback from Membrane Tension. iScience 2019; 15:173-184. [PMID: 31060000 PMCID: PMC6503128 DOI: 10.1016/j.isci.2019.04.021] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Revised: 02/08/2019] [Accepted: 04/17/2019] [Indexed: 01/08/2023] Open
Abstract
Artificial cells can shed new light on the molecular basis for life and hold potential for new chemical technologies. Inspired by how nature dynamically regulates its membrane compartments, we aim to repurpose the endosomal sorting complex required for transport (ESCRT) to generate complex membrane architectures as suitable scaffolds for artificial cells. Purified ESCRT-III components perform topological transformations on giant unilamellar vesicles to create complex “vesicles-within-a-vesicle” architectures resembling the compartmentalization in eukaryotic cells. Thus far, the proposed mechanisms for this activity are based on how assembly and disassembly of ESCRT-III on the membrane drives deformation. Here we demonstrate the existence of a negative feedback mechanism from membrane mechanics that regulates ESCRT-III remodeling activity. Intraluminal vesicle (ILV) formation removes excess membrane area, increasing tension, which in turn suppresses downstream ILV formation. This mechanism for in vitro regulation of ESCRT-III activity may also have important implications for its in vivo functions. ESCRT proteins are used to create compartmentalized artificial cell architectures In vitro ESCRT activity is weakly dependent on the stoichiometry of Vps20 or Vps24 ESCRT function is strongly regulated by membrane tension Membrane tension provides a negative feedback mechanism to attenuate remodeling
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Affiliation(s)
- Andrew Booth
- School of Chemistry and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK
| | - Christopher J Marklew
- Department of Chemistry and Centre for Membrane Interactions and Dynamics, University of Sheffield, Sheffield S3 7HF, UK
| | - Barbara Ciani
- Department of Chemistry and Centre for Membrane Interactions and Dynamics, University of Sheffield, Sheffield S3 7HF, UK.
| | - Paul A Beales
- School of Chemistry and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds LS2 9JT, UK.
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26
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Kinslechner K, Schütz B, Pistek M, Rapolter P, Weitzenböck HP, Hundsberger H, Mikulits W, Grillari J, Röhrl C, Hengstschläger M, Stangl H, Mikula M. Loss of SR-BI Down-Regulates MITF and Suppresses Extracellular Vesicle Release in Human Melanoma. Int J Mol Sci 2019; 20:E1063. [PMID: 30823658 PMCID: PMC6429474 DOI: 10.3390/ijms20051063] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 02/22/2019] [Accepted: 02/26/2019] [Indexed: 02/06/2023] Open
Abstract
Melanoma is a skin tumor with a high tendency for metastasis and thus is one of the deadliest cancers worldwide. Here, we investigated the expression of the scavenger receptor class B type 1 (SR-BI), a high-density lipoprotein (HDL) receptor, and tested for its role in melanoma pigmentation as well as extracellular vesicle release. We first analyzed the expression of SR-BI in patient samples and found a strong correlation with MITF expression as well as with the melanin synthesis pathway. Hence, we asked whether SR-BI could also play a role for the secretory pathway in metastatic melanoma cells. Interestingly, gain- and loss-of-function of SR-BI revealed regulation of the proto-oncogene MET. In line, SR-BI knockdown reduced expression of the small GTPase RABB22A, the ESCRT-II protein VPS25, and SNAP25, a member of the SNARE complex. Accordingly, reduced overall extracellular vesicle generation was detected upon loss of SR-BI. In summary, SR-BI expression in human melanoma enhances the formation and transport of extracellular vesicles, thereby contributing to the metastatic phenotype. Therapeutic targeting of SR-BI would not only interfere with cholesterol uptake, but also with the secretory pathway, therefore suppressing a key hallmark of the metastatic program.
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Affiliation(s)
- Katharina Kinslechner
- Center for Pathobiochemistry and Genetics, Medical University of Vienna, 1090 Vienna, Austria.
| | - Birgit Schütz
- Center for Pathobiochemistry and Genetics, Medical University of Vienna, 1090 Vienna, Austria.
| | - Martina Pistek
- Center for Pathobiochemistry and Genetics, Medical University of Vienna, 1090 Vienna, Austria.
| | - Philipp Rapolter
- Center for Pathobiochemistry and Genetics, Medical University of Vienna, 1090 Vienna, Austria.
| | - Hans P Weitzenböck
- Medical and Pharmaceutical Biotechnology, IMC University of Applied Sciences, 3500 Krems, Austria.
| | - Harald Hundsberger
- Medical and Pharmaceutical Biotechnology, IMC University of Applied Sciences, 3500 Krems, Austria.
| | - Wolfgang Mikulits
- Department of Medicine I, Division: Institute of Cancer Research, Comprehensive Cancer Center, Medical University of Vienna, 1090 Vienna, Austria.
| | - Johannes Grillari
- Department of Biotechnology, BOKU -University of Natural Resources and Life Sciences, 1190 Vienna, Austria.
| | - Clemens Röhrl
- Center for Pathobiochemistry and Genetics, Medical University of Vienna, 1090 Vienna, Austria.
| | - Markus Hengstschläger
- Center for Pathobiochemistry and Genetics, Medical University of Vienna, 1090 Vienna, Austria.
| | - Herbert Stangl
- Center for Pathobiochemistry and Genetics, Medical University of Vienna, 1090 Vienna, Austria.
| | - Mario Mikula
- Center for Pathobiochemistry and Genetics, Medical University of Vienna, 1090 Vienna, Austria.
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27
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The role of VPS4 in ESCRT-III polymer remodeling. Biochem Soc Trans 2019; 47:441-448. [DOI: 10.1042/bst20180026] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Revised: 01/16/2019] [Accepted: 01/21/2019] [Indexed: 01/04/2023]
Abstract
Abstract
The endosomal sorting complex required for transport-III (ESCRT-III) and VPS4 catalyze a variety of membrane-remodeling processes in eukaryotes and archaea. Common to these processes is the dynamic recruitment of ESCRT-III proteins from the cytosol to the inner face of a membrane neck structure, their activation and filament formation inside or at the membrane neck and the subsequent or concomitant recruitment of the AAA-type ATPase VPS4. The dynamic assembly of ESCRT-III filaments and VPS4 on cellular membranes induces constriction of membrane necks with large diameters such as the cytokinetic midbody and necks with small diameters such as those of intraluminal vesicles or enveloped viruses. The two processes seem to use different sets of ESCRT-III filaments. Constriction is then thought to set the stage for membrane fission. Here, we review recent progress in understanding the structural transitions of ESCRT-III proteins required for filament formation, the functional role of VPS4 in dynamic ESCRT-III assembly and its active role in filament constriction. The recent data will be discussed in the context of different mechanistic models for inside-out membrane fission.
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28
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McCullough J, Frost A, Sundquist WI. Structures, Functions, and Dynamics of ESCRT-III/Vps4 Membrane Remodeling and Fission Complexes. Annu Rev Cell Dev Biol 2018; 34:85-109. [PMID: 30095293 PMCID: PMC6241870 DOI: 10.1146/annurev-cellbio-100616-060600] [Citation(s) in RCA: 167] [Impact Index Per Article: 27.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The endosomal sorting complexes required for transport (ESCRT) pathway mediates cellular membrane remodeling and fission reactions. The pathway comprises five core complexes: ALIX, ESCRT-I, ESCRT-II, ESCRT-III, and Vps4. These soluble complexes are typically recruited to target membranes by site-specific adaptors that bind one or both of the early-acting ESCRT factors: ALIX and ESCRT-I/ESCRT-II. These factors, in turn, nucleate assembly of ESCRT-III subunits into membrane-bound filaments that recruit the AAA ATPase Vps4. Together, ESCRT-III filaments and Vps4 remodel and sever membranes. Here, we review recent advances in our understanding of the structures, activities, and mechanisms of the ESCRT-III and Vps4 machinery, including the first high-resolution structures of ESCRT-III filaments, the assembled Vps4 enzyme in complex with an ESCRT-III substrate, the discovery that ESCRT-III/Vps4 complexes can promote both inside-out and outside-in membrane fission reactions, and emerging mechanistic models for ESCRT-mediated membrane fission.
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Affiliation(s)
- John McCullough
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah 84112, USA;
| | - Adam Frost
- Department of Biochemistry and Biophysics, University of California, San Francisco, California 94158, USA
- Chan Zuckerberg Biohub, San Francisco, California 94158, USA
| | - Wesley I Sundquist
- Department of Biochemistry, University of Utah School of Medicine, Salt Lake City, Utah 84112, USA;
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29
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Cheng J, Yin Z, Zhang Z, Liang Y. Functional analysis of MoSnf7 in Magnaporthe oryzae. Fungal Genet Biol 2018; 121:29-45. [PMID: 30240788 DOI: 10.1016/j.fgb.2018.09.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 09/14/2018] [Accepted: 09/17/2018] [Indexed: 12/20/2022]
Abstract
Snf7 is the core subunit protein of the yeast endosomal sorting complex required for transport (ESCRT) complex, which plays important roles in endocytosis and autophagy. In this study, we characterized MoSnf7 in Magnaporthe oryzae, a homolog of yeast Snf7, the core protein of ESCRT-III subcomplex. Like Snf7, MoSnf7 also localizes next to the vacuoles. Deletion of MoSNF7 resulted in significant decrease in vegetative growth and pathogenicity. Further analyses of ΔMosnf7 mutants showed that they were defective in endocytosis, sexual and asexual development, turgor pressure maintenance of appressorium at hyphal tips, and cell wall integrity. Additional assays for the localization and degradation of GFP-MoAtg8 in ΔMosnf7 mutants showed that they were defective in autophagy pathway. Based on the roles of yeast Snf7 in endocytosis and autophagy, we propose that the decreased vegetative growth and pathogenicity of ΔMosnf7 rice blast fungus M. oryzae, was partly due to the conservative roles of MoSnf7 in vesicle trafficking and autophagy pathway.
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Affiliation(s)
- Jie Cheng
- Department of Microbiology, College of Life Sciences, Nanjing Agricultural University, and Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture and Rural Affairs, Nanjing 210095, China
| | - Ziyi Yin
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China
| | - Zhengguang Zhang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China
| | - Yongheng Liang
- Department of Microbiology, College of Life Sciences, Nanjing Agricultural University, and Key Laboratory of Agricultural Environmental Microbiology, Ministry of Agriculture and Rural Affairs, Nanjing 210095, China.
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30
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Marklew CJ, Booth A, Beales PA, Ciani B. Membrane remodelling by a lipidated endosomal sorting complex required for transport-III chimera, in vitro. Interface Focus 2018; 8:20180035. [PMID: 30443329 DOI: 10.1098/rsfs.2018.0035] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/17/2018] [Indexed: 01/28/2023] Open
Abstract
The complexity of eukaryotic cells is underscored by the compartmentalization of chemical signals by phospholipid membranes. A grand challenge of synthetic biology is building life from the 'bottom-up', for the purpose of generating systems simple enough to precisely interrogate biological pathways or for adapting biology to perform entirely novel functions. Achieving compartmentalization of chemistries in an addressable manner is a task exquisitely refined by nature and embodied in a unique membrane remodelling machinery that pushes membranes away from the cytosol, the ESCRT-III (endosomal sorting complex required for transport-III) complex. Here, we show efforts to engineer a single ESCRT-III protein merging functional features from its different components. The activity of such a designed ESCRT-III is shown by its ability to drive the formation of compartments encapsulating fluorescent cargo. It appears that the modular nature of ESCRT-III allows its functional repurposing into a minimal machinery that performs sophisticated membrane remodelling, therefore enabling its use to create eukaryotic-like multi-compartment architectures.
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Affiliation(s)
- C J Marklew
- Department of Chemistry and Centre for Membrane Interactions and Dynamics, University of Sheffield, Sheffield, UK
| | - A Booth
- School of Chemistry and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, UK
| | - P A Beales
- School of Chemistry and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, UK
| | - B Ciani
- Department of Chemistry and Centre for Membrane Interactions and Dynamics, University of Sheffield, Sheffield, UK
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31
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Emerman AB, Blower MD. The RNA-binding complex ESCRT-II in Xenopus laevis eggs recognizes purine-rich sequences through its subunit, Vps25. J Biol Chem 2018; 293:12593-12605. [PMID: 29903915 DOI: 10.1074/jbc.ra118.003718] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 06/12/2018] [Indexed: 12/29/2022] Open
Abstract
RNA-binding proteins (RBP) are critical regulators of gene expression. Recent studies have uncovered hundreds of mRNA-binding proteins that do not contain annotated RNA-binding domains and have well-established roles in other cellular processes. Investigation of these nonconventional RBPs is critical for revealing novel RNA-binding domains and may disclose connections between RNA regulation and other aspects of cell biology. The endosomal sorting complex required for transport II (ESCRT-II) is a nonconventional RNA-binding complex that has a canonical role in multivesicular body formation. ESCRT-II was identified previously as an RNA-binding complex in Drosophila oocytes, but whether its RNA-binding properties extend beyond Drosophila is unknown. In this study, we found that the RNA-binding properties of ESCRT-II are conserved in Xenopus eggs, where ESCRT-II interacted with hundreds of mRNAs. Using a UV cross-linking approach, we demonstrated that ESCRT-II binds directly to RNA through its subunit, Vps25. UV cross-linking and immunoprecipitation (CLIP)-Seq revealed that Vps25 specifically recognizes a polypurine (i.e. GA-rich) motif in RNA. Using purified components, we could reconstitute the selective Vps25-mediated binding of the polypurine motif in vitro Our results provide insight into the mechanism by which ESCRT-II selectively binds to mRNA and also suggest an unexpected link between endosome biology and RNA regulation.
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Affiliation(s)
- Amy B Emerman
- From the Department of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts 02114 and the Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115
| | - Michael D Blower
- From the Department of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts 02114 and the Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115
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Caspi Y, Dekker C. Dividing the Archaeal Way: The Ancient Cdv Cell-Division Machinery. Front Microbiol 2018; 9:174. [PMID: 29551994 PMCID: PMC5840170 DOI: 10.3389/fmicb.2018.00174] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 01/25/2018] [Indexed: 01/06/2023] Open
Abstract
Cell division in most prokaryotes is mediated by the well-studied fts genes, with FtsZ as the principal player. In many archaeal species, however, division is orchestrated differently. The Crenarchaeota phylum of archaea features the action of the three proteins, CdvABC. This Cdv system is a unique and less-well-studied division mechanism that merits closer inspection. In vivo, the three Cdv proteins form a composite band that contracts concomitantly with the septum formation. Of the three Cdv proteins, CdvA is the first to be recruited to the division site, while CdvB and CdvC are thought to participate in the active part of the Cdv division machinery. Interestingly, CdvB shares homology with a family of proteins from the eukaryotic ESCRT-III complex, and CdvC is a homolog of the eukaryotic Vps4 complex. These two eukaryotic complexes are key factors in the endosomal sorting complex required for transport (ESCRT) pathway, which is responsible for various budding processes in eukaryotic cells and which participates in the final stages of division in Metazoa. There, ESCRT-III forms a contractile machinery that actively cuts the membrane, whereas Vps4, which is an ATPase, is necessary for the turnover of the ESCRT membrane-abscission polymers. In contrast to CdvB and CdvC, CdvA is unique to the archaeal Crenarchaeota and Thaumarchaeota phyla. The Crenarchaeota division mechanism has often been suggested to represent a simplified version of the ESCRT division machinery thus providing a model system to study the evolution and mechanism of cell division in higher organisms. However, there are still many open questions regarding this parallelism and the division mechanism of Crenarchaeota. Here, we review the existing data on the role of the Cdv proteins in the division process of Crenarchaeota as well as concisely review the ESCRT system in eukaryotes. We survey the similarities and differences between the division and abscission mechanisms in the two cases. We suggest that the Cdv system functions differently in archaea than ESCRT does in eukaryotes, and that, unlike the eukaryotic case, the Cdv system's main function may be related to surplus membrane invagination and cell-wall synthesis.
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Affiliation(s)
- Yaron Caspi
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, Netherlands
| | - Cees Dekker
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Delft, Netherlands
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Wang S, Sun H, Tanowitz M, Liang XH, Crooke ST. Intra-endosomal trafficking mediated by lysobisphosphatidic acid contributes to intracellular release of phosphorothioate-modified antisense oligonucleotides. Nucleic Acids Res 2017; 45:5309-5322. [PMID: 28379543 PMCID: PMC5605259 DOI: 10.1093/nar/gkx231] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 03/27/2017] [Indexed: 12/12/2022] Open
Abstract
Antisense oligonucleotides (ASOs) with phosphorothioate (PS) linkages are broadly used as research tools and therapeutic agents. Chemically modified PS-ASOs can mediate efficient target reduction by site-specific cleavage of RNA through RNase H1. PS-ASOs are known to be internalized via a number of endocytotic pathways and are released from membrane-enclosed endocytotic organelles, mainly late endosomes (LEs). This study was focused on the details of PS-ASO trafficking through endocytic pathways. It was found that lysobisphosphatidic acid (LBPA) is required for release of PS-ASOs from LEs. PS-ASOs exited early endosomes (EEs) rapidly after internalization and became co-localized with LBPA by 2 hours in LEs. Inside LEs, PS-ASOs and LBPA were co-localized in punctate, dot-like structures, likely intraluminal vesicles (ILVs). Deactivation of LBPA using anti-LBPA antibody significantly decreased PS-ASO activities without affecting total PS-ASO uptake. Reduction of Alix also substantially decreased PS-ASO activities without affecting total PS-ASO uptake. Furthermore, Alix reduction decreased LBPA levels and limited co-localization of LBPA with PS-ASOs at ILVs inside LEs. Thus, the fusion properties of ILVs, which are supported by LBPA, contribute to PS-ASO intracellular release from LEs.
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Affiliation(s)
- Shiyu Wang
- Department of Core Antisense Research, Ionis Pharmaceuticals, Inc. 2855 Gazelle Court, Carlsbad, CA 92010, USA
| | - Hong Sun
- Department of Core Antisense Research, Ionis Pharmaceuticals, Inc. 2855 Gazelle Court, Carlsbad, CA 92010, USA
| | - Michael Tanowitz
- Department of Medicinal Chemistry, Ionis Pharmaceuticals, Inc. 2855 Gazelle Court, Carlsbad, CA 92010, USA
| | - Xue-Hai Liang
- Department of Core Antisense Research, Ionis Pharmaceuticals, Inc. 2855 Gazelle Court, Carlsbad, CA 92010, USA
| | - Stanley T Crooke
- Department of Core Antisense Research, Ionis Pharmaceuticals, Inc. 2855 Gazelle Court, Carlsbad, CA 92010, USA
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35
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Growing functions of the ESCRT machinery in cell biology and viral replication. Biochem Soc Trans 2017; 45:613-634. [PMID: 28620025 DOI: 10.1042/bst20160479] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Revised: 02/17/2017] [Accepted: 02/21/2017] [Indexed: 01/31/2023]
Abstract
The vast expansion in recent years of the cellular processes promoted by the endosomal sorting complex required for transport (ESCRT) machinery has reinforced its identity as a modular system that uses multiple adaptors to recruit the core membrane remodelling activity at different intracellular sites and facilitate membrane scission. Functional connections to processes such as the aurora B-dependent abscission checkpoint also highlight the importance of the spatiotemporal regulation of the ESCRT machinery. Here, we summarise the role of ESCRTs in viral budding, and what we have learned about the ESCRT pathway from studying this process. These advances are discussed in the context of areas of cell biology that have been transformed by research in the ESCRT field, including cytokinetic abscission, nuclear envelope resealing and plasma membrane repair.
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36
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Lippincott-Schwartz J, Freed EO, van Engelenburg SB. A Consensus View of ESCRT-Mediated Human Immunodeficiency Virus Type 1 Abscission. Annu Rev Virol 2017; 4:309-325. [PMID: 28715971 DOI: 10.1146/annurev-virology-101416-041840] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The strong dependence of retroviruses, such as human immunodeficiency virus type 1 (HIV-1), on host cell factors is no more apparent than when the endosomal sorting complex required for transport (ESCRT) machinery is purposely disengaged. The resulting potent inhibition of retrovirus release underscores the importance of understanding fundamental structure-function relationships at the ESCRT-HIV-1 interface. Recent studies utilizing advanced imaging technologies have helped clarify these relationships, overcoming hurdles to provide a range of potential models for ESCRT-mediated virus abscission. Here, we discuss these models in the context of prior work detailing ESCRT machinery and the HIV-1 release process. To provide a template for further refinement, we propose a new working model for ESCRT-mediated HIV-1 release that reconciles disparate and seemingly conflicting studies.
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Affiliation(s)
| | - E O Freed
- The Virus-Cell Interaction Section, HIV Dynamics and Replication Program, National Cancer Institute, Frederick, Maryland 21701
| | - S B van Engelenburg
- Department of Biological Sciences, University of Denver, Denver, Colorado 80210;
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Johnson N, West M, Odorizzi G. Regulation of yeast ESCRT-III membrane scission activity by the Doa4 ubiquitin hydrolase. Mol Biol Cell 2017; 28:661-672. [PMID: 28057764 PMCID: PMC5328624 DOI: 10.1091/mbc.e16-11-0761] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Revised: 12/15/2016] [Accepted: 12/30/2016] [Indexed: 11/23/2022] Open
Abstract
Doa4 is the ubiquitin hydrolase in yeast that deubiquitinates transmembrane proteins sorted by ESCRTs. Results support a model for bidirectional regulation between Doa4 and the ESCRT-III complex. ESCRT-III executes membrane scission during the budding of intralumenal vesicles (ILVs) at endosomes. The scission mechanism is unknown but appears to be linked to the cycle of assembly and disassembly of ESCRT-III complexes at membranes. Regulating this cycle is therefore expected to be important for determining the timing of ESCRT-III–mediated membrane scission. We show that in Saccharomyces cerevisiae, ESCRT-III complexes are stabilized and ILV membrane scission is delayed by Doa4, which is the ubiquitin hydrolase that deubiquitinates transmembrane proteins sorted as cargoes into ILVs. These results suggest a mechanism to delay ILV budding while cargoes undergo deubiquitination. We further show that deubiquitination of ILV cargoes is inhibited via Doa4 binding to Vps20, which is the subunit of ESCRT-III that initiates assembly of the complex. Current models suggest that ESCRT-III complexes surround ubiquitinated cargoes to trap them at the site of ILV budding while the cargoes undergo deubiquitination. Thus our results also propose a mechanism to prevent the onset of ILV cargo deubiquitination at the initiation of ESCRT-III complex assembly.
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Affiliation(s)
- Natalie Johnson
- Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, CO 80309
| | - Matt West
- Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, CO 80309
| | - Greg Odorizzi
- Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, CO 80309
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38
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Christ L, Raiborg C, Wenzel EM, Campsteijn C, Stenmark H. Cellular Functions and Molecular Mechanisms of the ESCRT Membrane-Scission Machinery. Trends Biochem Sci 2017; 42:42-56. [DOI: 10.1016/j.tibs.2016.08.016] [Citation(s) in RCA: 300] [Impact Index Per Article: 42.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 08/24/2016] [Accepted: 08/31/2016] [Indexed: 12/22/2022]
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Webster BM, Thaller DJ, Jäger J, Ochmann SE, Borah S, Lusk CP. Chm7 and Heh1 collaborate to link nuclear pore complex quality control with nuclear envelope sealing. EMBO J 2016; 35:2447-2467. [PMID: 27733427 DOI: 10.15252/embj.201694574] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2016] [Revised: 09/21/2016] [Accepted: 09/22/2016] [Indexed: 11/09/2022] Open
Abstract
The integrity of the nuclear envelope barrier relies on membrane remodeling by the ESCRTs, which seal nuclear envelope holes and contribute to the quality control of nuclear pore complexes (NPCs); whether these processes are mechanistically related remains poorly defined. Here, we show that the ESCRT-II/III chimera, Chm7, is recruited to a nuclear envelope subdomain that expands upon inhibition of NPC assembly and is required for the formation of the storage of improperly assembled NPCs (SINC) compartment. Recruitment to sites of NPC assembly is mediated by its ESCRT-II domain and the LAP2-emerin-MAN1 (LEM) family of integral inner nuclear membrane proteins, Heh1 and Heh2. We establish direct binding between Heh2 and the "open" forms of both Chm7 and the ESCRT-III, Snf7, and between Chm7 and Snf7. Interestingly, Chm7 is required for the viability of yeast strains where double membrane seals have been observed over defective NPCs; deletion of CHM7 in these strains leads to a loss of nuclear compartmentalization suggesting that the sealing of defective NPCs and nuclear envelope ruptures could proceed through similar mechanisms.
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Affiliation(s)
- Brant M Webster
- Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA
| | - David J Thaller
- Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA
| | - Jens Jäger
- Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA
| | - Sarah E Ochmann
- Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA
| | - Sapan Borah
- Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA
| | - C Patrick Lusk
- Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA
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40
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Olmos Y, Perdrix-Rosell A, Carlton JG. Membrane Binding by CHMP7 Coordinates ESCRT-III-Dependent Nuclear Envelope Reformation. Curr Biol 2016; 26:2635-2641. [PMID: 27618263 PMCID: PMC5069351 DOI: 10.1016/j.cub.2016.07.039] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 06/25/2016] [Accepted: 07/15/2016] [Indexed: 10/27/2022]
Abstract
In addition to its role in membrane abscission during cytokinesis, viral budding, endosomal sorting, and plasma membrane repair [1], the endosomal sorting complex required for transport-III (ESCRT-III) machinery has recently been shown to seal holes in the reforming nuclear envelope (NE) during mitotic exit [2, 3]. ESCRT-III also acts during interphase to repair the NE upon migration-induced rupture [4, 5], highlighting its key role as an orchestrator of membrane integrity at this organelle. While NE localization of ESCRT-III is dependent upon the ESCRT-III component CHMP7 [3], it is unclear how this complex is able to engage nuclear membranes. Here we show that the N terminus of CHMP7 acts as a novel membrane-binding module. This membrane-binding ability allows CHMP7 to bind to the ER, an organelle continuous with the NE, and it provides a platform to direct NE recruitment of ESCRT-III during mitotic exit. CHMP7's N terminus comprises tandem Winged-Helix domains [6], and, by using homology modeling and structure-function analysis, we identify point mutations that disrupt membrane binding and prevent both ER localization of CHMP7 and its subsequent enrichment at the reforming NE. These mutations also prevent assembly of downstream ESCRT-III components at the reforming NE and proper establishment of post-mitotic nucleo-cytoplasmic compartmentalization. These data identify a novel membrane-binding activity within an ESCRT-III subunit that is essential for post-mitotic nuclear regeneration.
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Affiliation(s)
- Yolanda Olmos
- Division of Cancer Studies, King's College London, London SE1 1UL, UK
| | | | - Jeremy G Carlton
- Division of Cancer Studies, King's College London, London SE1 1UL, UK.
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41
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Abstract
The narrow membrane necks formed during viral, exosomal and intra-endosomal budding from membranes, as well as during cytokinesis and related processes, have interiors that are contiguous with the cytosol. Severing these necks involves action from the opposite face of the membrane as occurs during the well-characterized formation of coated vesicles. This 'reverse' (or 'inverse')-topology membrane scission is carried out by the endosomal sorting complex required for transport (ESCRT) proteins, which form filaments, flat spirals, tubes and conical funnels that are thought to direct membrane remodelling and scission. Their assembly, and their disassembly by the ATPase vacuolar protein sorting-associated 4 (VPS4) have been intensively studied, but the mechanism of scission has been elusive. New insights from cryo-electron microscopy and various types of spectroscopy may finally be close to rectifying this situation.
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42
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Campsteijn C, Vietri M, Stenmark H. Novel ESCRT functions in cell biology: spiraling out of control? Curr Opin Cell Biol 2016; 41:1-8. [DOI: 10.1016/j.ceb.2016.03.008] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Revised: 03/08/2016] [Accepted: 03/11/2016] [Indexed: 01/05/2023]
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43
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Christ L, Wenzel EM, Liestøl K, Raiborg C, Campsteijn C, Stenmark H. ALIX and ESCRT-I/II function as parallel ESCRT-III recruiters in cytokinetic abscission. J Cell Biol 2016; 212:499-513. [PMID: 26929449 PMCID: PMC4772496 DOI: 10.1083/jcb.201507009] [Citation(s) in RCA: 103] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Cytokinetic abscission, the final stage of cell division, is mediated by the ESCRT machinery. Here, Christ et al. dissect the regulation of ESCRT-III recruitment and abscission timing and identify an intersection with abscission checkpoint signaling in cells with chromatin bridges. Cytokinetic abscission, the final stage of cell division where the two daughter cells are separated, is mediated by the endosomal sorting complex required for transport (ESCRT) machinery. The ESCRT-III subunit CHMP4B is a key effector in abscission, whereas its paralogue, CHMP4C, is a component in the abscission checkpoint that delays abscission until chromatin is cleared from the intercellular bridge. How recruitment of these components is mediated during cytokinesis remains poorly understood, although the ESCRT-binding protein ALIX has been implicated. Here, we show that ESCRT-II and the ESCRT-II–binding ESCRT-III subunit CHMP6 cooperate with ESCRT-I to recruit CHMP4B, with ALIX providing a parallel recruitment arm. In contrast to CHMP4B, we find that recruitment of CHMP4C relies predominantly on ALIX. Accordingly, ALIX depletion leads to furrow regression in cells with chromosome bridges, a phenotype associated with abscission checkpoint signaling failure. Collectively, our work reveals a two-pronged recruitment of ESCRT-III to the cytokinetic bridge and implicates ALIX in abscission checkpoint signaling.
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Affiliation(s)
- Liliane Christ
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, N-0379 Oslo, Norway Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, N-0379 Oslo, Norway
| | - Eva M Wenzel
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, N-0379 Oslo, Norway Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, N-0379 Oslo, Norway
| | - Knut Liestøl
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, N-0379 Oslo, Norway Department of Informatics, University of Oslo, N-0373 Oslo, Norway
| | - Camilla Raiborg
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, N-0379 Oslo, Norway Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, N-0379 Oslo, Norway
| | - Coen Campsteijn
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, N-0379 Oslo, Norway Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, N-0379 Oslo, Norway
| | - Harald Stenmark
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, N-0379 Oslo, Norway Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, N-0379 Oslo, Norway
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44
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Dores MR, Grimsey NJ, Mendez F, Trejo J. ALIX Regulates the Ubiquitin-Independent Lysosomal Sorting of the P2Y1 Purinergic Receptor via a YPX3L Motif. PLoS One 2016; 11:e0157587. [PMID: 27301021 PMCID: PMC4907476 DOI: 10.1371/journal.pone.0157587] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 06/01/2016] [Indexed: 12/22/2022] Open
Abstract
Endocytic sorting and lysosomal degradation are integral to the regulation of G protein-coupled receptor (GPCR) function. Upon ligand binding, classical GPCRs are activated, internalized and recycled or sorted to lysosomes for degradation, a process that requires receptor ubiquitination. However, recent studies have demonstrated that numerous GPCRs are sorted to lysosomes independent of receptor ubiquitination. Here, we describe an ubiquitin-independent lysosomal sorting pathway for the purinergic GPCR P2Y1. After activation, P2Y1 sorts to lysosomes for degradation independent of direct ubiquitination that is mediated by a YPX3L motif within the second intracellular loop that serves as a binding site for the adaptor protein ALIX. Depletion of ALIX or site-directed mutation of the YPX3L motif inhibits P2Y1 sorting into the lumen of multivesicular endosomes/lysosomes and degradation. These findings confirm the function of YPX3L motifs as lysosomal targeting sequences for GPCRs and demonstrate that ALIX mediates the ubiquitin-independent degradation of certain GPCRs.
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Affiliation(s)
- Michael R. Dores
- Department of Pharmacology, School of Medicine, University of California San Diego, La Jolla, CA 92093, United States of America
- Department of Biology, Hofstra University, Hempstead, NY 11549, United States of America
| | - Neil J. Grimsey
- Department of Pharmacology, School of Medicine, University of California San Diego, La Jolla, CA 92093, United States of America
| | - Francisco Mendez
- Department of Pharmacology, School of Medicine, University of California San Diego, La Jolla, CA 92093, United States of America
| | - JoAnn Trejo
- Department of Pharmacology, School of Medicine, University of California San Diego, La Jolla, CA 92093, United States of America
- * E-mail:
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45
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Abstract
The multivesicular body (MVB) pathway sorts ubiquitinated membrane cargo to intraluminal vesicles (ILVs) within the endosome, en route to the lysosomal lumen. The pathway involves the sequential action of conserved protein complexes [endosomal sorting complexes required for transport (ESCRTs)], culminating in the activation by ESCRT-II of ESCRT-III, a membrane-sculpting complex. Although this linear pathway of ESCRT activation is widely accepted, a study by Luzio and colleagues in a recent issue of the Biochemical Journal suggests that there is greater complexity in ESCRT-III activation, at least for some MVB cargoes. They show that ubiquitin-dependent sorting of major histocompatibility complex (MHC) class I to the MVB requires the central ESCRT-III complex but does not involve either ESCRT-II or functional links between ESCRT-II and ESCRT-III. Instead, they propose that MHC class I utilizes histidine-domain protein tyrosine phosphatase (HD-PTP), a non-canonical ESCRT interactor, to promote ESCRT-III activation.
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46
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Tang S, Buchkovich NJ, Henne WM, Banjade S, Kim YJ, Emr SD. ESCRT-III activation by parallel action of ESCRT-I/II and ESCRT-0/Bro1 during MVB biogenesis. eLife 2016; 5. [PMID: 27074665 PMCID: PMC4865371 DOI: 10.7554/elife.15507] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 04/11/2016] [Indexed: 11/13/2022] Open
Abstract
The endosomal sorting complexes required for transport (ESCRT) pathway facilitates multiple fundamental membrane remodeling events. Previously, we determined X-ray crystal structures of ESCRT-III subunit Snf7, the yeast CHMP4 ortholog, in its active and polymeric state (Tang et al., 2015). However, how ESCRT-III activation is coordinated by the upstream ESCRT components at endosomes remains unclear. Here, we provide a molecular explanation for the functional divergence of structurally similar ESCRT-III subunits. We characterize novel mutations in ESCRT-III Snf7 that trigger activation, and identify a novel role of Bro1, the yeast ALIX ortholog, in Snf7 assembly. We show that upstream ESCRTs regulate Snf7 activation at both its N-terminal core domain and the C-terminus α6 helix through two parallel ubiquitin-dependent pathways: the ESCRT-I-ESCRT-II-Vps20 pathway and the ESCRT-0-Bro1 pathway. We therefore provide an enhanced understanding for the activation of the spatially unique ESCRT-III-mediated membrane remodeling. DOI:http://dx.doi.org/10.7554/eLife.15507.001
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Affiliation(s)
- Shaogeng Tang
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, United States.,Department of Molecular Biology and Genetics, Cornell University, Ithaca, United States
| | - Nicholas J Buchkovich
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, United States.,Department of Molecular Biology and Genetics, Cornell University, Ithaca, United States
| | - W Mike Henne
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, United States.,Department of Molecular Biology and Genetics, Cornell University, Ithaca, United States
| | - Sudeep Banjade
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, United States.,Department of Molecular Biology and Genetics, Cornell University, Ithaca, United States
| | - Yun Jung Kim
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, United States.,Department of Molecular Biology and Genetics, Cornell University, Ithaca, United States
| | - Scott D Emr
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, United States.,Department of Molecular Biology and Genetics, Cornell University, Ithaca, United States
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47
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Closing a gap in the nuclear envelope. Curr Opin Cell Biol 2016; 40:90-97. [PMID: 27016712 DOI: 10.1016/j.ceb.2016.03.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Revised: 02/13/2016] [Accepted: 03/05/2016] [Indexed: 11/22/2022]
Abstract
The nuclear envelope (NE) ensures nucleo-cytoplasmic compartmentalization, with trafficking of macromolecules across this double membrane controlled by embedded nuclear pore complexes (NPCs). The NE and associated proteins are dismantled during open mitosis and reestablishment of this barrier during mitotic exit requires dynamic remodeling of endoplasmic reticulum (ER) membranes and coordination with NPC reformation, with NPC deposition continuing during subsequent interphase. In this review, we discuss recent progress in our understanding of NE reformation and nuclear pore complex generation, with special focus on work implicating the endosomal sorting complex required for transport (ESCRT) membrane remodeling machinery in these events.
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48
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Alonso Y Adell M, Migliano SM, Teis D. ESCRT-III and Vps4: a dynamic multipurpose tool for membrane budding and scission. FEBS J 2016; 283:3288-302. [PMID: 26910595 DOI: 10.1111/febs.13688] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Revised: 01/19/2016] [Accepted: 02/17/2016] [Indexed: 12/11/2022]
Abstract
Complex molecular machineries bud, scission and repair cellular membranes. Components of the multi-subunit endosomal sorting complex required for transport (ESCRT) machinery are enlisted when multivesicular bodies are generated, extracellular vesicles are formed, the plasma membrane needs to be repaired, enveloped viruses bud out of host cells, defective nuclear pores have to be cleared, the nuclear envelope must be resealed after mitosis and for final midbody abscission during cytokinesis. While some ESCRT components are only required for specific processes, the assembly of ESCRT-III polymers on target membranes and the action of the AAA-ATPase Vps4 are mandatory for every process. In this review, we summarize the current knowledge of structural and functional features of ESCRT-III/Vps4 assemblies in the growing pantheon of ESCRT-dependent pathways. We describe specific recruitment processes for ESCRT-III to different membranes, which could be useful to selectively inhibit ESCRT function during specific processes, while not affecting other ESCRT-dependent processes. Finally, we speculate how ESCRT-III and Vps4 might function together and highlight how the characterization of their precise spatiotemporal organization will improve our understanding of ESCRT-mediated membrane budding and scission in vivo.
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Affiliation(s)
| | - Simona M Migliano
- Division of Cell Biology, Biocenter, Medical University of Innsbruck, Austria
| | - David Teis
- Division of Cell Biology, Biocenter, Medical University of Innsbruck, Austria.
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49
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Tang S, Henne WM, Borbat PP, Buchkovich NJ, Freed JH, Mao Y, Fromme JC, Emr SD. Structural basis for activation, assembly and membrane binding of ESCRT-III Snf7 filaments. eLife 2015; 4:e12548. [PMID: 26670543 PMCID: PMC4720517 DOI: 10.7554/elife.12548] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2015] [Accepted: 12/13/2015] [Indexed: 12/14/2022] Open
Abstract
The endosomal sorting complexes required for transport (ESCRTs) constitute hetero-oligomeric machines that catalyze multiple topologically similar membrane-remodeling processes. Although ESCRT-III subunits polymerize into spirals, how individual ESCRT-III subunits are activated and assembled together into a membrane-deforming filament remains unknown. Here, we determine X-ray crystal structures of the most abundant ESCRT-III subunit Snf7 in its active conformation. Using pulsed dipolar electron spin resonance spectroscopy (PDS), we show that Snf7 activation requires a prominent conformational rearrangement to expose protein-membrane and protein-protein interfaces. This promotes the assembly of Snf7 arrays with ~30 Å periodicity into a membrane-sculpting filament. Using a combination of biochemical and genetic approaches, both in vitro and in vivo, we demonstrate that mutations on these protein interfaces halt Snf7 assembly and block ESCRT function. The architecture of the activated and membrane-bound Snf7 polymer provides crucial insights into the spatially unique ESCRT-III-mediated membrane remodeling.
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Affiliation(s)
- Shaogeng Tang
- Weill Institute of Cell and Molecular Biology, Cornell University, Ithaca, United States
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, United States
| | - W Mike Henne
- Weill Institute of Cell and Molecular Biology, Cornell University, Ithaca, United States
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, United States
| | - Peter P Borbat
- National Biomedical Center for Advanced Electron Spin Resonance Technology, Cornell University, Ithaca, United States
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, United States
| | - Nicholas J Buchkovich
- Weill Institute of Cell and Molecular Biology, Cornell University, Ithaca, United States
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, United States
| | - Jack H Freed
- National Biomedical Center for Advanced Electron Spin Resonance Technology, Cornell University, Ithaca, United States
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, United States
| | - Yuxin Mao
- Weill Institute of Cell and Molecular Biology, Cornell University, Ithaca, United States
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, United States
| | - J Christopher Fromme
- Weill Institute of Cell and Molecular Biology, Cornell University, Ithaca, United States
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, United States
| | - Scott D Emr
- Weill Institute of Cell and Molecular Biology, Cornell University, Ithaca, United States
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, United States
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Negative membrane curvature catalyzes nucleation of endosomal sorting complex required for transport (ESCRT)-III assembly. Proc Natl Acad Sci U S A 2015; 112:15892-7. [PMID: 26668364 DOI: 10.1073/pnas.1518765113] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The endosomal sorting complexes required for transport (ESCRT) machinery functions in HIV-1 budding, cytokinesis, multivesicular body biogenesis, and other pathways, in the course of which it interacts with concave membrane necks and bud rims. To test the role of membrane shape in regulating ESCRT assembly, we nanofabricated templates for invaginated supported lipid bilayers. The assembly of the core ESCRT-III subunit CHMP4B/Snf7 is preferentially nucleated in the resulting 100-nm-deep membrane concavities. ESCRT-II and CHMP6 accelerate CHMP4B assembly by increasing the concentration of nucleation seeds. Superresolution imaging was used to visualize CHMP4B/Snf7 concentration in a negatively curved annulus at the rim of the invagination. Although Snf7 assemblies nucleate slowly on flat membranes, outward growth onto the flat membrane is efficiently nucleated at invaginations. The nucleation behavior provides a biophysical explanation for the timing of ESCRT-III recruitment and membrane scission in HIV-1 budding.
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