1
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Shimizu H, Hosseini-Alghaderi S, Woodcock SA, Baron M. Alternative mechanisms of Notch activation by partitioning into distinct endosomal domains. J Cell Biol 2024; 223:e202211041. [PMID: 38358349 PMCID: PMC10868400 DOI: 10.1083/jcb.202211041] [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: 11/11/2022] [Revised: 11/17/2023] [Accepted: 01/30/2024] [Indexed: 02/16/2024] Open
Abstract
Different membrane microdomain compositions provide unique environments that can regulate signaling receptor function. We identify microdomains on the endosome membrane of Drosophila endosomes, enriched in lipid-raft or clathrin/ESCRT-0, which are associated with Notch activation by distinct, ligand-independent mechanisms. Transfer of Notch between microdomains is regulated by Deltex and Suppressor of deltex ubiquitin ligases and is limited by a gate-keeper role for ESCRT complexes. Ubiquitination of Notch by Deltex recruits it to the clathrin/ESCRT-0 microdomain and enhances Notch activation by an ADAM10-independent/TRPML-dependent mechanism. This requirement for Deltex is bypassed by the downregulation of ESCRT-III. In contrast, while ESCRT-I depletion also activates Notch, it does so by an ADAM10-dependent/TRPML-independent mechanism and Notch is retained in the lipid raft-like microdomain. In the absence of such endosomal perturbation, different activating Notch mutations also localize to different microdomains and are activated by different mechanisms. Our findings demonstrate the interplay between Notch regulators, endosomal trafficking components, and Notch genetics, which defines membrane locations and activation mechanisms.
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Affiliation(s)
- Hideyuki Shimizu
- School of Biological Sciences, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK
| | - Samira Hosseini-Alghaderi
- School of Biological Sciences, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK
| | - Simon A. Woodcock
- School of Biological Sciences, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK
| | - Martin Baron
- School of Biological Sciences, Manchester Academic Health Science Centre, University of Manchester, Manchester, UK
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2
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Vassilopoulos S, Montagnac G. Clathrin assemblies at a glance. J Cell Sci 2024; 137:jcs261674. [PMID: 38668719 DOI: 10.1242/jcs.261674] [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: 05/01/2024] Open
Abstract
Clathrin assembles into honeycomb-like lattices at the plasma membrane but also on internal membranes, such as at the Golgi and tubular endosomes. Clathrin assemblies primarily regulate the intracellular trafficking of different cargoes, but clathrin also has non-endocytic functions in cell adhesion through interactions with specific integrins, contributes to intraluminal vesicle formation by forming flat bilayered coats on endosomes and even assembles on kinetochore k-fibers during mitosis. In this Cell Science at a Glance article and the accompanying poster, we review our current knowledge on the different types of canonical and non-canonical membrane-associated clathrin assemblies in mammalian cells, as observed by thin-section or platinum replica electron microscopy in various cell types, and discuss how the structural plasticity of clathrin contributes to its functional diversity.
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Affiliation(s)
- Stéphane Vassilopoulos
- Sorbonne Université, Inserm U974, Institut de Myologie, Centre de Recherche en Myologie, 75013 Paris, France
| | - Guillaume Montagnac
- Inserm U1279, Gustave Roussy Institute, Université Paris-Saclay, 94800 Villejuif, France
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3
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Swords SB, Jia N, Norris A, Modi J, Cai Q, Grant BD. A conserved requirement for RME-8/DNAJC13 in neuronal autophagic lysosome reformation. Autophagy 2024; 20:792-808. [PMID: 37942902 PMCID: PMC11062384 DOI: 10.1080/15548627.2023.2269028] [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: 03/09/2023] [Accepted: 10/02/2023] [Indexed: 11/10/2023] Open
Abstract
Autophagosomes fuse with lysosomes, forming autolysosomes that degrade engulfed cargo. To maintain lysosomal capacity, autophagic lysosome reformation (ALR) must regenerate lysosomes from autolysosomes using a membrane tubule-based process. Maintaining lysosomal capacity is required to maintain cellular health, especially in neurons where lysosomal dysfunction has been repeatedly implicated in neurodegenerative disease. The DNA-J domain HSC70 co-chaperone RME-8/DNAJC13 has been linked to endosomal coat protein regulation and to neurological disease. We report new analysis of the requirements for the RME-8/DNAJC13 protein in neurons, focusing on intact C. elegans mechanosensory neurons, and primary mouse cortical neurons in culture. Loss of RME-8/DNAJC13 in both systems results in accumulation of grossly elongated autolysosomal tubules. Further C. elegans analysis revealed a similar autolysosome tubule accumulation defect in mutants known to be required for ALR in mammals, including mutants lacking bec-1/BECN1/Beclin1 and vps-15/PIK3R4/p150 that regulate the class III phosphatidylinositol 3-kinase (PtdIns3K) VPS-34, and dyn-1/dynamin that severs ALR tubules. Clathrin is also an important ALR regulator implicated in autolysosome tubule formation and release. In C. elegans we found that loss of RME-8 causes severe depletion of clathrin from neuronal autolysosomes, a phenotype shared with bec-1 and vps-15 mutants. We conclude that RME-8/DNAJC13 plays a previously unrecognized role in ALR, likely affecting autolysosome tubule severing. Additionally, in both systems, loss of RME-8/DNAJC13 reduced macroautophagic/autophagic flux, suggesting feedback regulation from ALR to autophagy. Our results connecting RME-8/DNAJC13 to ALR and autophagy provide a potential mechanism by which RME-8/DNAJC13 could influence neuronal health and the progression of neurodegenerative disease.Abbreviation: ALR, autophagic lysosome reformation; ATG-13/EPG-1, AuTophaGy (yeast Atg homolog)-13; ATG-18, AuTophaGy (yeast Atg homolog)-18; AV, autophagic vacuole; CLIC-1, Clathrin Light Chain-1; EPG-3, Ectopic P Granules-3; EPG-6, Ectopic P Granules-6; LGG-1, LC3, GABARAP and GATE-16 family-1; MAP1LC3/LC3, microtubule-associated protein 1 light chain 3; PD, Parkinson disease; PtdIns3P, phosphatidylinositol-3-phosphate; PtdIns(4,5)P2, phosphatidylinositol-4,5-bisphosphate; RME-8, Receptor Mediated Endocytosis-8; SNX-1, Sorting NeXin-1; VPS-34, related to yeast Vacuolar Protein Sorting factor-34.
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Affiliation(s)
- Sierra B. Swords
- Department of Molecular Biology and Biochemistry, Rutgers University, Piscataway, NJ, USA
| | - Nuo Jia
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ, USA
| | - Anne Norris
- Department of Molecular Biology and Biochemistry, Rutgers University, Piscataway, NJ, USA
| | - Jil Modi
- Department of Molecular Biology and Biochemistry, Rutgers University, Piscataway, NJ, USA
| | - Qian Cai
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ, USA
| | - Barth D. Grant
- Department of Molecular Biology and Biochemistry, Rutgers University, Piscataway, NJ, USA
- Center for Lipid Research, New Brunswick, NJ, USA
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4
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Schultz DF, Billadeau DD, Jois SD. EGFR trafficking: effect of dimerization, dynamics, and mutation. Front Oncol 2023; 13:1258371. [PMID: 37752992 PMCID: PMC10518470 DOI: 10.3389/fonc.2023.1258371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 08/21/2023] [Indexed: 09/28/2023] Open
Abstract
Spontaneous dimerization of EGF receptors (EGFR) and dysregulation of EGFR signaling has been associated with the development of different cancers. Under normal physiological conditions and to maintain homeostatic cell growth, once EGFR signaling occurs, it needs to be attenuated. Activated EGFRs are rapidly internalized, sorted through early endosomes, and ultimately degraded in lysosomes by a process generally known as receptor down-regulation. Through alterations to EGFR trafficking, tumors develop resistance to current treatment strategies, thus highlighting the necessity for combination treatment strategies that target EGFR trafficking. This review covers EGFR structure, trafficking, and altered surface expression of EGFR receptors in cancer, with a focus on how therapy targeting EGFR trafficking may aid tyrosine kinase inhibitor treatment of cancer.
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Affiliation(s)
| | - Daniel D. Billadeau
- Department of Immunology, Mayo Clinic, Rochester, MN, United States
- Division of Oncology Research, Mayo Clinic, Rochester, MN, United States
| | - Seetharama D. Jois
- Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA, United States
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5
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Dixson AC, Dawson TR, Di Vizio D, Weaver AM. Context-specific regulation of extracellular vesicle biogenesis and cargo selection. Nat Rev Mol Cell Biol 2023; 24:454-476. [PMID: 36765164 PMCID: PMC10330318 DOI: 10.1038/s41580-023-00576-0] [Citation(s) in RCA: 114] [Impact Index Per Article: 114.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/04/2023] [Indexed: 02/12/2023]
Abstract
To coordinate, adapt and respond to biological signals, cells convey specific messages to other cells. An important aspect of cell-cell communication involves secretion of molecules into the extracellular space. How these molecules are selected for secretion has been a fundamental question in the membrane trafficking field for decades. Recently, extracellular vesicles (EVs) have been recognized as key players in intercellular communication, carrying not only membrane proteins and lipids but also RNAs, cytosolic proteins and other signalling molecules to recipient cells. To communicate the right message, it is essential to sort cargoes into EVs in a regulated and context-specific manner. In recent years, a wealth of lipidomic, proteomic and RNA sequencing studies have revealed that EV cargo composition differs depending upon the donor cell type, metabolic cues and disease states. Analyses of distinct cargo 'fingerprints' have uncovered mechanistic linkages between the activation of specific molecular pathways and cargo sorting. In addition, cell biology studies are beginning to reveal novel biogenesis mechanisms regulated by cellular context. Here, we review context-specific mechanisms of EV biogenesis and cargo sorting, focusing on how cell signalling and cell state influence which cellular components are ultimately targeted to EVs.
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Affiliation(s)
- Andrew C Dixson
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - T Renee Dawson
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, USA
- Center for Extracellular Vesicle Research, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Dolores Di Vizio
- Department of Surgery, Division of Cancer Biology and Therapeutics, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Alissa M Weaver
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, USA.
- Center for Extracellular Vesicle Research, Vanderbilt University School of Medicine, Nashville, TN, USA.
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA.
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6
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Gonçalves D, Pinto SN, Fernandes F. Extracellular Vesicles and Infection: From Hijacked Machinery to Therapeutic Tools. Pharmaceutics 2023; 15:1738. [PMID: 37376186 DOI: 10.3390/pharmaceutics15061738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 06/12/2023] [Accepted: 06/13/2023] [Indexed: 06/29/2023] Open
Abstract
Extracellular vesicles (EVs) comprise a broad range of secreted cell-derived membrane vesicles. Beyond their more well-characterized role in cell communication, in recent years, EVs have also been shown to play important roles during infection. Viruses can hijack the biogenesis of exosomes (which are small EVs) to promote viral spreading. Additionally, these exosomes are also important mediators in inflammation and immune responses during both bacterial and viral infections. This review summarizes these mechanisms while also describing the impact of bacterial EVs in regulating immune responses. Finally, the review also focuses on the potential and challenges of using EVs, in particular, to tackle infectious diseases.
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Affiliation(s)
- Diogo Gonçalves
- iBB-Institute for Bioengineering and Biosciences and i4HB-Institute for Health and Bioeconomy, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
| | - Sandra N Pinto
- iBB-Institute for Bioengineering and Biosciences and i4HB-Institute for Health and Bioeconomy, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
| | - Fábio Fernandes
- iBB-Institute for Bioengineering and Biosciences and i4HB-Institute for Health and Bioeconomy, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
- Bioengineering Department, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal
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7
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Lin H, Deaton CA, Johnson GVW. Commentary: BAG3 as a Mediator of Endosome Function and Tau Clearance. Neuroscience 2023; 518:4-9. [PMID: 35550160 PMCID: PMC9646927 DOI: 10.1016/j.neuroscience.2022.05.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 04/12/2022] [Accepted: 05/03/2022] [Indexed: 12/25/2022]
Abstract
Tauopathies are a group of heterogeneous neurodegenerative conditions characterized by the deposition of abnormal tau protein in the brain. The underlying mechanisms that contribute to the accumulation of tau in these neurodegenerative diseases are multifactorial; nonetheless, there is a growing awareness that dysfunction of endosome-lysosome pathways is a pivotal factor. BCL2 associated athanogene 3 (BAG3) is a multidomain protein that plays a key role in maintaining neuronal proteostasis. Further, recent data indicate that BAG3 plays an important role in mediating vacuolar-dependent degradation of tau. Overexpression of BAG3 in a tauopathy mouse model decreased pathological tau levels and alleviated synapse loss. High throughput screens of BAG3 interactors have identified key players in the vacuolar system; these include clathrin and regulators of small GTPases. These findings suggest that BAG3 is an important regulator of endocytic pathways. In this commentary, we discuss the potential mechanisms by which BAG3 regulates the vacuolar system and tau proteostasis.
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Affiliation(s)
- Heng Lin
- Department of Anesthesiology and Perioperative Medicine, University of Rochester, 601 Elmwood Ave, Box 604, Rochester, NY 14642, USA
| | - Carol A Deaton
- Department of Anesthesiology and Perioperative Medicine, University of Rochester, 601 Elmwood Ave, Box 604, Rochester, NY 14642, USA
| | - Gail V W Johnson
- Department of Anesthesiology and Perioperative Medicine, University of Rochester, 601 Elmwood Ave, Box 604, Rochester, NY 14642, USA.
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8
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Hanafusa H, Fujita K, Kamio M, Iida S, Tamura Y, Hisamoto N, Matsumoto K. LRRK1 functions as a scaffold for PTP1B-mediated EGFR sorting into ILVs at the ER-endosome contact site. J Cell Sci 2023; 136:286918. [PMID: 36744428 PMCID: PMC10022742 DOI: 10.1242/jcs.260566] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Accepted: 01/30/2023] [Indexed: 02/07/2023] Open
Abstract
Proper control of epidermal growth factor receptor (EGFR) signaling is important for maintaining cellular homeostasis. Given that EGFR signaling occurs at the plasma membrane and endosomes following internalization, endosomal trafficking of EGFR spatiotemporally regulates EGFR signaling. In this process, leucine-rich repeat kinase 1 (LRRK1) has multiple roles in kinase activity-dependent transport of EGFR-containing endosomes and kinase-independent sorting of EGFR into the intraluminal vesicles (ILVs) of multivesicular bodies. Active, phosphorylated EGFR inactivates the LRRK1 kinase activity by phosphorylating Y944. In this study, we demonstrate that LRRK1 facilitates EGFR dephosphorylation by PTP1B (also known as PTPN1), an endoplasmic reticulum (ER)-localized protein tyrosine phosphatase, at the ER-endosome contact site, after which EGFR is sorted into the ILVs of endosomes. LRRK1 is required for the PTP1B-EGFR interaction in response to EGF stimulation, resulting in the downregulation of EGFR signaling. Furthermore, PTP1B activates LRRK1 by dephosphorylating pY944 on the contact site, which promotes the transport of EGFR-containing endosomes to the perinuclear region. These findings provide evidence that the ER-endosome contact site functions as a hub for LRRK1-dependent signaling that regulates EGFR trafficking.
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Affiliation(s)
- Hiroshi Hanafusa
- Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya 464-8602, Japan
| | - Keitaro Fujita
- Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya 464-8602, Japan
| | - Misa Kamio
- Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya 464-8602, Japan
| | - Shiori Iida
- Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya 464-8602, Japan
| | - Yasushi Tamura
- Department of Chemistry, Faculty of Science, Yamagata University, Shirakawa, Yamagata 990-8560, Japan
| | - Naoki Hisamoto
- Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya 464-8602, Japan
| | - Kunihiro Matsumoto
- Division of Biological Science, Graduate School of Science, Nagoya University, Chikusa-ku, Nagoya 464-8602, Japan
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9
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Mardi N, Haiaty S, Rahbarghazi R, Mobarak H, Milani M, Zarebkohan A, Nouri M. Exosomal transmission of viruses, a two-edged biological sword. Cell Commun Signal 2023; 21:19. [PMID: 36691072 PMCID: PMC9868521 DOI: 10.1186/s12964-022-01037-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Accepted: 12/28/2022] [Indexed: 01/24/2023] Open
Abstract
As a common belief, most viruses can egress from the host cells as single particles and transmit to uninfected cells. Emerging data have revealed en bloc viral transmission as lipid bilayer-cloaked particles via extracellular vesicles especially exosomes (Exo). The supporting membrane can be originated from multivesicular bodies during intra-luminal vesicle formation and autophagic response. Exo are nano-sized particles, ranging from 40-200 nm, with the ability to harbor several types of signaling molecules from donor to acceptor cells in a paracrine manner, resulting in the modulation of specific signaling reactions in target cells. The phenomenon of Exo biogenesis consists of multiple and complex biological steps with the participation of diverse constituents and molecular pathways. Due to similarities between Exo biogenesis and virus replication and the existence of shared pathways, it is thought that viruses can hijack the Exo biogenesis machinery to spread and evade immune cells. To this end, Exo can transmit complete virions (as single units or aggregates), separate viral components, and naked genetic materials. The current review article aims to scrutinize challenges and opportunities related to the exosomal delivery of viruses in terms of viral infections and public health. Video Abstract.
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Affiliation(s)
- Narges Mardi
- Department of Medical Biotechnology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Sanya Haiaty
- Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Reza Rahbarghazi
- Stem Cell Research Center, Tabriz University of Medical Sciences, Imam Reza St., Golgasht St., Tabriz, Iran
- Department of Applied Cell Sciences, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Halimeh Mobarak
- Stem Cell Research Center, Tabriz University of Medical Sciences, Imam Reza St., Golgasht St., Tabriz, Iran
| | - Morteza Milani
- Department of Medical Biotechnology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Amir Zarebkohan
- Department of Medical Nanotechnology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammad Nouri
- Department of Medical Biotechnology, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
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10
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Qu Q, Fu B, Long Y, Liu ZY, Tian XH. Current Strategies for Promoting the Large-scale Production of Exosomes. Curr Neuropharmacol 2023; 21:1964-1979. [PMID: 36797614 PMCID: PMC10514529 DOI: 10.2174/1570159x21666230216095938] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Revised: 10/21/2022] [Accepted: 11/05/2022] [Indexed: 02/18/2023] Open
Abstract
Exosomes, as nanoscale biological vesicles, have been shown to have great potential for biomedical applications. However, the low yield of exosomes limits their application. In this review, we focus on methods to increase exosome yield. Two main strategies are used to increase exosome production, one is based on genetic manipulation of the exosome biogenesis and release pathway, and the other is by pretreating parent cells, changing the culture method or adding different components to the medium. By applying these strategies, exosomes can be produced on a large scale to facilitate their practical application in the clinic.
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Affiliation(s)
- Qing Qu
- Department of Tissue Engineering, School of Intelligent Medicine, China Medical University, 77 Puhe Avenue, Shenbei New District, Shenyang, 110122, China
| | - Bin Fu
- Department of Tissue Engineering, School of Intelligent Medicine, China Medical University, 77 Puhe Avenue, Shenbei New District, Shenyang, 110122, China
| | - Yong Long
- Department of Tissue Engineering, School of Intelligent Medicine, China Medical University, 77 Puhe Avenue, Shenbei New District, Shenyang, 110122, China
| | - Zi-Yu Liu
- Department of Tissue Engineering, School of Intelligent Medicine, China Medical University, 77 Puhe Avenue, Shenbei New District, Shenyang, 110122, China
| | - Xiao-Hong Tian
- Department of Tissue Engineering, School of Intelligent Medicine, China Medical University, 77 Puhe Avenue, Shenbei New District, Shenyang, 110122, China
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11
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Enrich C, Lu A, Tebar F, Rentero C, Grewal T. Ca 2+ and Annexins - Emerging Players for Sensing and Transferring Cholesterol and Phosphoinositides via Membrane Contact Sites. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1422:393-438. [PMID: 36988890 DOI: 10.1007/978-3-031-21547-6_15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
Abstract
Maintaining lipid composition diversity in membranes from different organelles is critical for numerous cellular processes. However, many lipids are synthesized in the endoplasmic reticulum (ER) and require delivery to other organelles. In this scenario, formation of membrane contact sites (MCS) between neighbouring organelles has emerged as a novel non-vesicular lipid transport mechanism. Dissecting the molecular composition of MCS identified phosphoinositides (PIs), cholesterol, scaffolding/tethering proteins as well as Ca2+ and Ca2+-binding proteins contributing to MCS functioning. Compelling evidence now exists for the shuttling of PIs and cholesterol across MCS, affecting their concentrations in distinct membrane domains and diverse roles in membrane trafficking. Phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) at the plasma membrane (PM) not only controls endo-/exocytic membrane dynamics but is also critical in autophagy. Cholesterol is highly concentrated at the PM and enriched in recycling endosomes and Golgi membranes. MCS-mediated cholesterol transfer is intensely researched, identifying MCS dysfunction or altered MCS partnerships to correlate with de-regulated cellular cholesterol homeostasis and pathologies. Annexins, a conserved family of Ca2+-dependent phospholipid binding proteins, contribute to tethering and untethering events at MCS. In this chapter, we will discuss how Ca2+ homeostasis and annexins in the endocytic compartment affect the sensing and transfer of cholesterol and PIs across MCS.
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Affiliation(s)
- Carlos Enrich
- Departament de Biomedicina, Unitat de Biologia Cel⋅lular, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.
- Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain.
| | - Albert Lu
- Departament de Biomedicina, Unitat de Biologia Cel⋅lular, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain
| | - Francesc Tebar
- Departament de Biomedicina, Unitat de Biologia Cel⋅lular, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain
| | - Carles Rentero
- Departament de Biomedicina, Unitat de Biologia Cel⋅lular, Centre de Recerca Biomèdica CELLEX, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, Barcelona, Spain
| | - Thomas Grewal
- School of Pharmacy, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia
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12
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Zeng EZ, Chen I, Chen X, Yuan X. Exosomal MicroRNAs as Novel Cell-Free Therapeutics in Tissue Engineering and Regenerative Medicine. Biomedicines 2022; 10:biomedicines10102485. [PMID: 36289747 PMCID: PMC9598823 DOI: 10.3390/biomedicines10102485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Revised: 09/06/2022] [Accepted: 09/22/2022] [Indexed: 11/17/2022] Open
Abstract
Extracellular vesicles (EVs) are membrane-bound vesicles (50–1000 nm) that can be secreted by all cell types. Microvesicles and exosomes are the major subsets of EVs that exhibit the cell–cell communications and pathological functions of human tissues, and their therapeutic potentials. To further understand and engineer EVs for cell-free therapy, current developments in EV biogenesis and secretion pathways are discussed to illustrate the remaining gaps in EV biology. Specifically, microRNAs (miRs), as a major EV cargo that exert promising therapeutic results, are discussed in the context of biological origins, sorting and packing, and preclinical applications in disease progression and treatments. Moreover, advanced detection and engineering strategies for exosomal miRs are also reviewed. This article provides sufficient information and knowledge for the future design of EVs with specific miRs or protein cargos in tissue repair and regeneration.
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Affiliation(s)
- Eric Z. Zeng
- Department of Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Florida State University, Tallahassee, FL 32310, USA
| | - Isabelle Chen
- Department of Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Florida State University, Tallahassee, FL 32310, USA
- Los Altos High School, Los Altos, CA 94022, USA
| | - Xingchi Chen
- Department of Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Florida State University, Tallahassee, FL 32310, USA
| | - Xuegang Yuan
- Department of Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Florida State University, Tallahassee, FL 32310, USA
- Department of Pathology & Laboratory Medicine, David Geffen School of Medicine, University of California-Los Angeles (UCLA), Los Angeles, CA 95616, USA
- Correspondence: or
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13
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Perez Verdaguer M, Zhang T, Surve S, Paulo JA, Wallace C, Watkins SC, Gygi SP, Sorkin A. Time-resolved proximity labeling of protein networks associated with ligand-activated EGFR. Cell Rep 2022; 39:110950. [PMID: 35705039 PMCID: PMC9248364 DOI: 10.1016/j.celrep.2022.110950] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 04/13/2022] [Accepted: 05/22/2022] [Indexed: 11/26/2022] Open
Abstract
Ligand binding to the EGF receptor (EGFR) triggers multiple signal-transduction processes and promotes endocytosis of the receptor. The mechanisms of EGFR endocytosis and its cross-talk with signaling are poorly understood. Here, we combine peroxidase-catalyzed proximity labeling, isobaric peptide tagging, and quantitative mass spectrometry to define the dynamics of the proximity proteome of ligand-activated EGFR. Using this approach, we identify a network of signaling proteins, which remain associated with the receptor during its internalization and trafficking through the endosomal system. We show that Trk-fused gene (TFG), a protein known to function at the endoplasmic reticulum exit sites, is enriched in the proximity proteome of EGFR in early/sorting endosomes and localized in these endosomes and demonstrate that TFG regulates endosomal sorting of EGFR. This study provides a comprehensive resource of time-dependent nanoscale environment of EGFR, thus opening avenues to discovering new regulatory mechanisms of signaling and intracellular trafficking of receptor tyrosine kinases. Perez Verdaguer et al. use time-resolved APEX labeling of the proximity proteome of EGFR upon ligand activation to provide comprehensive information about the dynamics of the EGFR-associated protein networks involved in receptor endocytosis and signaling.
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Affiliation(s)
- Mireia Perez Verdaguer
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Tian Zhang
- Department of Cell Biology, Harvard University Medical School, Boston, MA, USA
| | - Sachin Surve
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Joao A Paulo
- Department of Cell Biology, Harvard University Medical School, Boston, MA, USA
| | - Callen Wallace
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Simon C Watkins
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Steven P Gygi
- Department of Cell Biology, Harvard University Medical School, Boston, MA, USA.
| | - Alexander Sorkin
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
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14
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Blanchette CR, Scalera AL, Harris KP, Zhao Z, Dresselhaus EC, Koles K, Yeh A, Apiki JK, Stewart BA, Rodal AA. Local regulation of extracellular vesicle traffic by the synaptic endocytic machinery. J Cell Biol 2022; 221:e202112094. [PMID: 35320349 PMCID: PMC8952828 DOI: 10.1083/jcb.202112094] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 02/14/2022] [Accepted: 02/28/2022] [Indexed: 02/01/2023] Open
Abstract
Neuronal extracellular vesicles (EVs) are locally released from presynaptic terminals, carrying cargoes critical for intercellular signaling and disease. EVs are derived from endosomes, but it is unknown how these cargoes are directed to the EV pathway rather than for conventional endolysosomal degradation. Here, we find that endocytic machinery plays an unexpected role in maintaining a release-competent pool of EV cargoes at synapses. Endocytic mutants, including nervous wreck (nwk), shibire/dynamin, and AP-2, unexpectedly exhibit local presynaptic depletion specifically of EV cargoes. Accordingly, nwk mutants phenocopy synaptic plasticity defects associated with loss of the EV cargo synaptotagmin-4 (Syt4) and suppress lethality upon overexpression of the EV cargo amyloid precursor protein (APP). These EV defects are genetically separable from canonical endocytic functions in synaptic vesicle recycling and synaptic growth. Endocytic machinery opposes the endosomal retromer complex to regulate EV cargo levels and acts upstream of synaptic cargo removal by retrograde axonal transport. Our data suggest a novel molecular mechanism that locally promotes cargo loading into synaptic EVs.
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Affiliation(s)
| | | | - Kathryn P. Harris
- Department of Biology, University of Toronto Mississauga, Mississauga, Canada
- Department of Cell and Systems Biology, University of Toronto, Toronto, Canada
| | - Zechuan Zhao
- Department of Biology, Brandeis University, Waltham, MA
| | | | - Kate Koles
- Department of Biology, Brandeis University, Waltham, MA
| | - Anna Yeh
- Department of Biology, Brandeis University, Waltham, MA
| | | | - Bryan A. Stewart
- Department of Biology, University of Toronto Mississauga, Mississauga, Canada
- Department of Cell and Systems Biology, University of Toronto, Toronto, Canada
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15
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Migliano SM, Wenzel EM, Stenmark H. Biophysical and molecular mechanisms of ESCRT functions, and their implications for disease. Curr Opin Cell Biol 2022; 75:102062. [DOI: 10.1016/j.ceb.2022.01.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 01/14/2022] [Accepted: 01/22/2022] [Indexed: 12/31/2022]
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16
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Gock N, Follett J, Rintoul GL, Beischlag TV, Lee FJ. Endosomal recycling and dopamine neurotransmission: Exploring the links between the retromer and Parkinson's disease. Synapse 2022; 76:e22224. [DOI: 10.1002/syn.22224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 12/17/2021] [Accepted: 01/23/2022] [Indexed: 11/11/2022]
Affiliation(s)
- Nathan Gock
- Faculty of Health Sciences Simon Fraser University 8888 University Dr Burnaby BC V5A 1S6 Canada
- Centre for Cell Biology, Development, and Disease Simon Fraser University 8888 University Dr Burnaby BC V5A 1S6 Canada
| | - Jordan Follett
- Laboratory of Neurogenetics and Neuroscience Department of Neurology University of Florida 1149 Newell Dr Gainesville FL 32610‐0236 United States
| | - Gordon L Rintoul
- Department of Biological Sciences Simon Fraser University 8888 University Dr Burnaby BC V5A 1S6 Canada
- Centre for Cell Biology, Development, and Disease Simon Fraser University 8888 University Dr Burnaby BC V5A 1S6 Canada
| | - Timothy V Beischlag
- Faculty of Health Sciences Simon Fraser University 8888 University Dr Burnaby BC V5A 1S6 Canada
- Centre for Cell Biology, Development, and Disease Simon Fraser University 8888 University Dr Burnaby BC V5A 1S6 Canada
| | - Frank J.S. Lee
- Faculty of Health Sciences Simon Fraser University 8888 University Dr Burnaby BC V5A 1S6 Canada
- Centre for Cell Biology, Development, and Disease Simon Fraser University 8888 University Dr Burnaby BC V5A 1S6 Canada
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17
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van der Beek J, de Heus C, Liv N, Klumperman J. Quantitative correlative microscopy reveals the ultrastructural distribution of endogenous endosomal proteins. J Cell Biol 2022; 221:212877. [PMID: 34817533 PMCID: PMC8624803 DOI: 10.1083/jcb.202106044] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 10/22/2021] [Accepted: 11/01/2021] [Indexed: 02/07/2023] Open
Abstract
The key endosomal regulators Rab5, EEA1, and APPL1 are frequently applied in fluorescence microscopy to mark early endosomes, whereas Rab7 is used as a marker for late endosomes and lysosomes. However, endogenous levels of these proteins localize poorly in immuno-EM, and systematic studies on their native ultrastructural distributions are lacking. To address this gap, we here present a quantitative, on-section correlative light and electron microscopy (CLEM) approach. Using the sensitivity of fluorescence microscopy, we label hundreds of organelles that are subsequently visualized by EM and classified by ultrastructure. We show that Rab5 predominantly marks small, endocytic vesicles and early endosomes. EEA1 colocalizes with Rab5 on early endosomes, but unexpectedly also labels Rab5-negative late endosomes, which are positive for PI(3)P but lack Rab7. APPL1 is restricted to small Rab5-positive, tubulo-vesicular profiles. Rab7 primarily labels late endosomes and lysosomes. These data increase our understanding of the structural-functional organization of the endosomal system and introduce quantitative CLEM as a sensitive alternative for immuno-EM.
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Affiliation(s)
- Jan van der Beek
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Institute of Biomembranes, Utrecht University, Utrecht, the Netherlands
| | - Cecilia de Heus
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Institute of Biomembranes, Utrecht University, Utrecht, the Netherlands
| | - Nalan Liv
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Institute of Biomembranes, Utrecht University, Utrecht, the Netherlands
| | - Judith Klumperman
- Section Cell Biology, Center for Molecular Medicine, University Medical Center Utrecht, Institute of Biomembranes, Utrecht University, Utrecht, the Netherlands
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18
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Kazan JM, Desrochers G, Martin CE, Jeong H, Kharitidi D, Apaja PM, Roldan A, St. Denis N, Gingras AC, Lukacs GL, Pause A. Endofin is required for HD-PTP and ESCRT-0 interdependent endosomal sorting of ubiquitinated transmembrane cargoes. iScience 2021; 24:103274. [PMID: 34761192 PMCID: PMC8567383 DOI: 10.1016/j.isci.2021.103274] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 08/18/2021] [Accepted: 10/12/2021] [Indexed: 11/20/2022] Open
Abstract
Internalized and ubiquitinated signaling receptors are silenced by their intraluminal budding into multivesicular bodies aided by the endosomal sorting complexes required for transport (ESCRT) machinery. HD-PTP, an ESCRT protein, forms complexes with ESCRT-0, -I and -III proteins, and binds to Endofin, a FYVE-domain protein confined to endosomes with poorly understood roles. Using proximity biotinylation, we showed that Endofin forms a complex with ESCRT constituents and Endofin depletion increased integrin α5-and EGF-receptor plasma membrane density and stability by hampering their lysosomal delivery. This coincided with sustained receptor signaling and increased cell migration. Complementation of Endofin- or HD-PTP-depleted cells with wild-type Endofin or HD-PTP, but not with mutants harboring impaired Endofin/HD-PTP association or cytosolic Endofin, restored EGFR lysosomal delivery. Endofin also promoted Hrs indirect interaction with HD-PTP. Jointly, our results indicate that Endofin is required for HD-PTP and ESCRT-0 interdependent sorting of ubiquitinated transmembrane cargoes to ensure efficient receptor desensitization and lysosomal delivery.
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Affiliation(s)
- Jalal M. Kazan
- Goodman Cancer Research Center, McGill University, Montreal, QC H3A 1A3, Canada
- Biochemistry Department, McGill University, Montreal, QC H3G 1Y6, Canada
| | - Guillaume Desrochers
- Goodman Cancer Research Center, McGill University, Montreal, QC H3A 1A3, Canada
- Biochemistry Department, McGill University, Montreal, QC H3G 1Y6, Canada
| | - Claire E. Martin
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, ON M5G 1X5, Canada
| | - Hyeonju Jeong
- Goodman Cancer Research Center, McGill University, Montreal, QC H3A 1A3, Canada
- Biochemistry Department, McGill University, Montreal, QC H3G 1Y6, Canada
| | - Dmitri Kharitidi
- Goodman Cancer Research Center, McGill University, Montreal, QC H3A 1A3, Canada
- Biochemistry Department, McGill University, Montreal, QC H3G 1Y6, Canada
| | - Pirjo M. Apaja
- Physiology Department, McGill University, Montreal, QC H3G 1Y6, Canada
| | - Ariel Roldan
- Physiology Department, McGill University, Montreal, QC H3G 1Y6, Canada
| | - Nicole St. Denis
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, ON M5G 1X5, Canada
| | - Anne-Claude Gingras
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, ON M5G 1X5, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Gergely L. Lukacs
- Biochemistry Department, McGill University, Montreal, QC H3G 1Y6, Canada
- Physiology Department, McGill University, Montreal, QC H3G 1Y6, Canada
| | - Arnim Pause
- Goodman Cancer Research Center, McGill University, Montreal, QC H3A 1A3, Canada
- Biochemistry Department, McGill University, Montreal, QC H3G 1Y6, Canada
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19
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Placidi G, Campa CC. Deliver on Time or Pay the Fine: Scheduling in Membrane Trafficking. Int J Mol Sci 2021; 22:11773. [PMID: 34769203 PMCID: PMC8583995 DOI: 10.3390/ijms222111773] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 10/23/2021] [Accepted: 10/27/2021] [Indexed: 12/12/2022] Open
Abstract
Membrane trafficking is all about time. Automation in such a biological process is crucial to ensure management and delivery of cellular cargoes with spatiotemporal precision. Shared molecular regulators and differential engagement of trafficking components improve robustness of molecular sorting. Sequential recruitment of low affinity protein complexes ensures directionality of the process and, concomitantly, serves as a kinetic proofreading mechanism to discriminate cargoes from the whole endocytosed material. This strategy helps cells to minimize losses and operating errors in membrane trafficking, thereby matching the appealed deadline. Here, we summarize the molecular pathways of molecular sorting, focusing on their timing and efficacy. We also highlight experimental procedures and genetic approaches to robustly probe these pathways, in order to guide mechanistic studies at the interface between biochemistry and quantitative biology.
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Affiliation(s)
- Giampaolo Placidi
- Italian Institute for Genomic Medicine, c/o IRCCS, Str. Prov.le 142, km 3.95, 10060 Candiolo, Italy;
- Candiolo Cancer Institute, FPO-IRCCS, Str. Prov.le 142, km 3.95, 10060 Candiolo, Italy
| | - Carlo C. Campa
- Italian Institute for Genomic Medicine, c/o IRCCS, Str. Prov.le 142, km 3.95, 10060 Candiolo, Italy;
- Candiolo Cancer Institute, FPO-IRCCS, Str. Prov.le 142, km 3.95, 10060 Candiolo, Italy
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20
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Štimac I, Jug Vučko N, Blagojević Zagorac G, Marcelić M, Mahmutefendić Lučin H, Lučin P. Dynamin Inhibitors Prevent the Establishment of the Cytomegalovirus Assembly Compartment in the Early Phase of Infection. Life (Basel) 2021; 11:life11090876. [PMID: 34575026 PMCID: PMC8469281 DOI: 10.3390/life11090876] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 08/21/2021] [Accepted: 08/23/2021] [Indexed: 12/30/2022] Open
Abstract
Cytomegalovirus (CMV) infection initiates massive rearrangement of cytoplasmic organelles to generate assembly compartment (AC). The earliest events, the establishment of the preAC, are initiated in the early phase as an extensive reorganization of early endosomes (EEs), endosomal recycling compartment (ERC), trans-Golgi network (TGN), and the Golgi. Here, we demonstrate that dynamin inhibitors (Dynasore, Dyngo-4a, MiTMAB, and Dynole-34-2) block the establishment of the preAC in murine CMV (MCMV) infected cells. In this study, we extensively analyzed the effect of Dynasore on the Golgi reorganization sequence into the outer preAC. We also monitored the development of the inner preAC using a set of markers that define EEs (Rab5, Vps34, EEA1, and Hrs), the EE-ERC interface (Rab10), the ERC (Rab11, Arf6), three layers of the Golgi (GRASP65, GM130, Golgin97), and late endosomes (Lamp1). Dynasore inhibited the pericentriolar accumulation of all markers that display EE-ERC-TGN interface in the inner preAC and prevented Golgi unlinking and dislocation to the outer preAC. Furthermore, in pulse-chase experiments, we demonstrated that the presence of dynasore only during the early phase of MCMV infection (4-14 hpi) is sufficient to prevent not only AC formation but also the synthesis of late-phase proteins and virion production. Therefore, our results indicate that dynamin-2 acts as a part of the machinery required for AC generation and rearrangement of EE/ERC/Golgi membranes in the early phase of CMV infection.
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Affiliation(s)
- Igor Štimac
- Department of Physiology and Immunology, Faculty of Medicine, University of Rijeka, 51000 Rijeka, Croatia; (I.Š.); (N.J.V.); (G.B.Z.); (M.M.); (P.L.)
| | - Natalia Jug Vučko
- Department of Physiology and Immunology, Faculty of Medicine, University of Rijeka, 51000 Rijeka, Croatia; (I.Š.); (N.J.V.); (G.B.Z.); (M.M.); (P.L.)
| | - Gordana Blagojević Zagorac
- Department of Physiology and Immunology, Faculty of Medicine, University of Rijeka, 51000 Rijeka, Croatia; (I.Š.); (N.J.V.); (G.B.Z.); (M.M.); (P.L.)
- Nursing Department, University North, University Center Varaždin, Jurja Križanića 31b, 42000 Varaždin, Croatia
| | - Marina Marcelić
- Department of Physiology and Immunology, Faculty of Medicine, University of Rijeka, 51000 Rijeka, Croatia; (I.Š.); (N.J.V.); (G.B.Z.); (M.M.); (P.L.)
| | - Hana Mahmutefendić Lučin
- Department of Physiology and Immunology, Faculty of Medicine, University of Rijeka, 51000 Rijeka, Croatia; (I.Š.); (N.J.V.); (G.B.Z.); (M.M.); (P.L.)
- Nursing Department, University North, University Center Varaždin, Jurja Križanića 31b, 42000 Varaždin, Croatia
- Correspondence:
| | - Pero Lučin
- Department of Physiology and Immunology, Faculty of Medicine, University of Rijeka, 51000 Rijeka, Croatia; (I.Š.); (N.J.V.); (G.B.Z.); (M.M.); (P.L.)
- Nursing Department, University North, University Center Varaždin, Jurja Križanića 31b, 42000 Varaždin, Croatia
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21
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Coudert L, Osseni A, Gangloff YG, Schaeffer L, Leblanc P. The ESCRT-0 subcomplex component Hrs/Hgs is a master regulator of myogenesis via modulation of signaling and degradation pathways. BMC Biol 2021; 19:153. [PMID: 34330273 PMCID: PMC8323235 DOI: 10.1186/s12915-021-01091-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Accepted: 07/09/2021] [Indexed: 11/30/2022] Open
Abstract
Background Myogenesis is a highly regulated process ending with the formation of myotubes, the precursors of skeletal muscle fibers. Differentiation of myoblasts into myotubes is controlled by myogenic regulatory factors (MRFs) that act as terminal effectors of signaling cascades involved in the temporal and spatial regulation of muscle development. Such signaling cascades converge and are controlled at the level of intracellular trafficking, but the mechanisms by which myogenesis is regulated by the endosomal machinery and trafficking is largely unexplored. The Endosomal Sorting Complex Required for Transport (ESCRT) machinery composed of four complexes ESCRT-0 to ESCRT-III regulates the biogenesis and trafficking of endosomes as well as the associated signaling and degradation pathways. Here, we investigate its role in regulating myogenesis. Results We uncovered a new function of the ESCRT-0 hepatocyte growth factor-regulated tyrosine kinase substrate Hrs/Hgs component in the regulation of myogenesis. Hrs depletion strongly impairs the differentiation of murine and human myoblasts. In the C2C12 murine myogenic cell line, inhibition of differentiation was attributed to impaired MRF in the early steps of differentiation. This alteration is associated with an upregulation of the MEK/ERK signaling pathway and a downregulation of the Akt2 signaling both leading to the inhibition of differentiation. The myogenic repressors FOXO1 as well as GSK3β were also found to be both activated when Hrs was absent. Inhibition of the MEK/ERK pathway or of GSK3β by the U0126 or azakenpaullone compounds respectively significantly restores the impaired differentiation observed in Hrs-depleted cells. In addition, functional autophagy that is required for myogenesis was also found to be strongly inhibited. Conclusions We show for the first time that Hrs/Hgs is a master regulator that modulates myogenesis at different levels through the control of trafficking, signaling, and degradation pathways. Supplementary Information The online version contains supplementary material available at 10.1186/s12915-021-01091-4.
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Affiliation(s)
- L Coudert
- Institut NeuroMyoGène, CNRS UMR5310, INSERM U1217, Faculté de Médecine Rockefeller, Université Claude Bernard Lyon, 8 avenue Rockefeller, 69373, 09, Lyon, Cedex, France
| | - A Osseni
- Institut NeuroMyoGène, CNRS UMR5310, INSERM U1217, Faculté de Médecine Rockefeller, Université Claude Bernard Lyon, 8 avenue Rockefeller, 69373, 09, Lyon, Cedex, France
| | - Y G Gangloff
- Institut NeuroMyoGène, CNRS UMR5310, INSERM U1217, Faculté de Médecine Rockefeller, Université Claude Bernard Lyon, 8 avenue Rockefeller, 69373, 09, Lyon, Cedex, France
| | - L Schaeffer
- Institut NeuroMyoGène, CNRS UMR5310, INSERM U1217, Faculté de Médecine Rockefeller, Université Claude Bernard Lyon, 8 avenue Rockefeller, 69373, 09, Lyon, Cedex, France
| | - P Leblanc
- Institut NeuroMyoGène, CNRS UMR5310, INSERM U1217, Faculté de Médecine Rockefeller, Université Claude Bernard Lyon, 8 avenue Rockefeller, 69373, 09, Lyon, Cedex, France.
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22
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Turegano-Lopez M, Santuy A, DeFelipe J, Merchan-Perez A. Size, Shape, and Distribution of Multivesicular Bodies in the Juvenile Rat Somatosensory Cortex: A 3D Electron Microscopy Study. Cereb Cortex 2021; 30:1887-1901. [PMID: 31665237 PMCID: PMC7132939 DOI: 10.1093/cercor/bhz211] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 07/30/2019] [Accepted: 08/16/2019] [Indexed: 12/27/2022] Open
Abstract
Multivesicular bodies (MVBs) are membrane-bound organelles that belong to the endosomal pathway. They participate in the transport, sorting, storage, recycling, degradation, and release of multiple substances. They interchange cargo with other organelles and participate in their renovation and degradation. We have used focused ion beam milling and scanning electron microscopy (FIB-SEM) to obtain stacks of serial sections from the neuropil of the somatosensory cortex of the juvenile rat. Using dedicated software, we have 3D-reconstructed 1618 MVBs. The mean density of MVBs was 0.21 per cubic micron. They were unequally distributed between dendrites (39.14%), axons (18.16%), and nonsynaptic cell processes (42.70%). About one out of five MVBs (18.16%) were docked on mitochondria, representing the process by which the endosomal pathway participates in mitochondrial maintenance. Other features of MVBs, such as the presence of tubular protrusions (6.66%) or clathrin coats (19.74%) can also be interpreted in functional terms, since both are typical of early endosomes. The sizes of MVBs follow a lognormal distribution, with differences across cortical layers and cellular compartments. The mean volume of dendritic MVBs is more than twice as large as the volume of axonic MVBs. In layer I, they are smaller, on average, than in the other layers.
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Affiliation(s)
- M Turegano-Lopez
- Laboratorio Cajal de Circuitos Corticales, Centro de Tecnología Biomédica, Universidad Politécnica de Madrid, Pozuelo de Alarcón, 28223 Madrid, Spain
| | - A Santuy
- Laboratorio Cajal de Circuitos Corticales, Centro de Tecnología Biomédica, Universidad Politécnica de Madrid, Pozuelo de Alarcón, 28223 Madrid, Spain
| | - J DeFelipe
- Laboratorio Cajal de Circuitos Corticales, Centro de Tecnología Biomédica, Universidad Politécnica de Madrid, Pozuelo de Alarcón, 28223 Madrid, Spain.,Instituto Cajal, Consejo Superior de Investigaciones Científicas (CSIC), Avda Doctor Arce, 37, 28002 Madrid, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED) ISCIII, Madrid, Spain
| | - A Merchan-Perez
- Laboratorio Cajal de Circuitos Corticales, Centro de Tecnología Biomédica, Universidad Politécnica de Madrid, Pozuelo de Alarcón, 28223 Madrid, Spain.,Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED) ISCIII, Madrid, Spain.,Departamento de Arquitectura y Tecnología de Sistemas Informáticos, Universidad Politécnica de Madrid, Pozuelo de Alarcón, 28223 Madrid, Spain
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23
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Dynamic control of the dopamine transporter in neurotransmission and homeostasis. NPJ Parkinsons Dis 2021; 7:22. [PMID: 33674612 PMCID: PMC7935902 DOI: 10.1038/s41531-021-00161-2] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 01/08/2021] [Indexed: 01/31/2023] Open
Abstract
The dopamine transporter (DAT) transports extracellular dopamine into the intracellular space contributing to the regulation of dopamine neurotransmission. A reduction of DAT density is implicated in Parkinson's disease (PD) by neuroimaging; dopamine turnover is dopamine turnover is elevated in early symptomatic PD and in presymptomatic individuals with monogenic mutations causal for parkinsonism. As an integral plasma membrane protein, DAT surface expression is dynamically regulated through endocytic trafficking, enabling flexible control of dopamine signaling in time and space, which in turn critically modulates movement, motivation and learning behavior. Yet the cellular machinery and functional implications of DAT trafficking remain enigmatic. In this review we summarize mechanisms governing DAT trafficking under normal physiological conditions and discuss how PD-linked mutations may disturb DAT homeostasis. We highlight the complexity of DAT trafficking and reveal DAT dysregulation as a common theme in genetic models of parkinsonism.
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24
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Conrad KP. Might proton pump or sodium-hydrogen exchanger inhibitors be of value to ameliorate SARs-CoV-2 pathophysiology? Physiol Rep 2021; 8:e14649. [PMID: 33369281 PMCID: PMC7762781 DOI: 10.14814/phy2.14649] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Revised: 09/17/2020] [Accepted: 09/18/2020] [Indexed: 12/26/2022] Open
Abstract
Discovering therapeutics for COVID-19 is a priority. Besides high-throughput screening of compounds, candidates might be identified based on their known mechanisms of action and current understanding of the SARs-CoV-2 life cycle. Using this approach, proton pump (PPIs) and sodium-hydrogen exchanger inhibitors (NHEIs) emerged, because of their potential to inhibit the release of extracellular vesicles (EVs; exosomes and/or microvesicles) that could promote disease progression, and to directly disrupt SARs-CoV-2 pathogenesis. If EVs exacerbate SARs-CoV-2 infection as suggested for other viruses, then inhibiting EV release by PPIs/NHEIs should be beneficial. Mechanisms underlying inhibition of EV release by these drugs remain uncertain, but may involve perturbing endosomal pH especially of multivesicular bodies where intraluminal vesicles (nascent exosomes) are formed. Additionally, PPIs might inhibit the endosomal sorting complex for transport machinery involved in EV biogenesis. Through perturbing endocytic vesicle pH, PPIs/NHEIs could also impede cleavage of SARs-CoV-2 spike protein by cathepsins necessary for viral fusion with the endosomal membrane. Although pulmonary epithelial cells may rely mainly on plasma membrane serine protease TMPRSS2 for cell entry, PPIs/NHEIs might be efficacious in ACE2-expressing cells where viral endocytosis is the major or a contributing entry pathway. These pharmaceutics might also perturb pH in the endoplasmic reticulum-Golgi intermediate and Golgi compartments, thereby potentially disrupting viral assembly and glycosylation of spike protein/ACE2, respectively. A caveat, however, is that facilitation not inhibition of avian infectious bronchitis CoV pathogenesis was reported in one study after increasing Golgi pH. Envelope protein-derived viroporins contributed to pulmonary edema formation in mice infected with SARs-CoV. If similar pathogenesis occurs with SARs-CoV-2, then blocking these channels with NHEIs could ameliorate disease pathogenesis. To ascertain their potential efficacy, PPIs/NHEIs need evaluation in cell and animal models at various phases of SARs-CoV-2 infection. If they prove to be therapeutic, the greatest benefit might be realized with the administration before the onset of severe cytokine release syndrome.
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Affiliation(s)
- Kirk P. Conrad
- Departments of Physiology and Functional Genomics, and of Obstetrics and GynecologyUniversity of Florida College of MedicineGainesvilleFLUSA
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Protein crowding mediates membrane remodeling in upstream ESCRT-induced formation of intraluminal vesicles. Proc Natl Acad Sci U S A 2020; 117:28614-28624. [PMID: 33139578 DOI: 10.1073/pnas.2014228117] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
As part of the lysosomal degradation pathway, the endosomal sorting complexes required for transport (ESCRT-0 to -III/VPS4) sequester receptors at the endosome and simultaneously deform the membrane to generate intraluminal vesicles (ILVs). Whereas ESCRT-III/VPS4 have an established function in ILV formation, the role of upstream ESCRTs (0 to II) in membrane shape remodeling is not understood. Combining experimental measurements and electron microscopy analysis of ESCRT-III-depleted cells with a mathematical model, we show that upstream ESCRT-induced alteration of the Gaussian bending rigidity and their crowding in concert with the transmembrane cargo on the membrane induce membrane deformation and facilitate ILV formation: Upstream ESCRT-driven budding does not require ATP consumption as only a small energy barrier needs to be overcome. Our model predicts that ESCRTs do not become part of the ILV, but localize with a high density at the membrane neck, where the steep decline in the Gaussian curvature likely triggers ESCRT-III/VPS4 assembly to enable neck constriction and scission.
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Norris A, Grant BD. Endosomal microdomains: Formation and function. Curr Opin Cell Biol 2020; 65:86-95. [PMID: 32247230 PMCID: PMC7529669 DOI: 10.1016/j.ceb.2020.02.018] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 02/24/2020] [Accepted: 02/25/2020] [Indexed: 12/18/2022]
Abstract
It is widely recognized that after endocytosis, internalized cargo is delivered to endosomes that act as sorting stations. The limiting membrane of endosomes contain specialized subregions, or microdomains, that represent distinct functions of the endosome, including regions competing for cargo capture leading to degradation or recycling. Great progress has been made in defining the endosomal protein coats that sort cargo in these domains, including Retromer that recycles transmembrane cargo, and ESCRT (endosomal sorting complex required for transport) that degrades transmembrane cargo. In this review, we discuss recent work that is beginning to unravel how such coat complexes contribute to the creation and maintenance of endosomal microdomains. We highlight data that indicates that adjacent microdomains do not act independently but rather interact to cross-regulate. We posit that these interactions provide an agile means for the cell to adjust sorting in response to extracellular signals and intracellular metabolic cues.
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Affiliation(s)
- Anne Norris
- Rutgers University, Department of Molecular Biology and Biochemistry, Piscataway, NJ, 08854, USA
| | - Barth D Grant
- Rutgers University, Department of Molecular Biology and Biochemistry, Piscataway, NJ, 08854, USA.
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Munthe E, Raiborg C, Stenmark H, Wenzel EM. Clathrin regulates Wnt/β-catenin signaling by affecting Golgi to plasma membrane transport of transmembrane proteins. J Cell Sci 2020; 133:jcs244467. [PMID: 32546530 DOI: 10.1242/jcs.244467] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 06/04/2020] [Indexed: 12/19/2022] Open
Abstract
The canonical Wnt/β-catenin signaling pathway regulates cell proliferation in development and adult tissue homeostasis. Dysregulated signaling contributes to human diseases, in particular cancer. Growing evidence suggests a role for clathrin and/or endocytosis in the regulation of this pathway, but conflicting results exist and demand a deeper mechanistic understanding. We investigated the consequences of clathrin depletion on Wnt/β-catenin signaling in cell lines and found a pronounced reduction in β-catenin protein levels, which affects the amount of nuclear β-catenin and β-catenin target gene expression. Although we found no evidence that clathrin affects β-catenin levels via endocytosis or multivesicular endosome formation, an inhibition of protein transport through the biosynthetic pathway led to reduced levels of a Wnt co-receptor, low-density lipoprotein receptor-related protein 6 (LRP6), and cell adhesion molecules of the cadherin family, thereby affecting steady-state levels of β-catenin. We conclude that clathrin impacts on Wnt/β-catenin signaling by controlling exocytosis of transmembrane proteins, including cadherins and Wnt co-receptors that together control the membrane-bound and soluble pools of β-catenin.
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Affiliation(s)
- Else Munthe
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, N-0379 Oslo, Norway
- Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, N-0316 Oslo, Norway
| | - Camilla Raiborg
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, N-0379 Oslo, Norway
- Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, N-0316 Oslo, Norway
| | - Harald Stenmark
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, N-0379 Oslo, Norway
- Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, N-0316 Oslo, Norway
| | - Eva Maria Wenzel
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, N-0379 Oslo, Norway
- Centre for Cancer Cell Reprogramming, Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, N-0316 Oslo, Norway
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Botté A, Lainé J, Xicota L, Heiligenstein X, Fontaine G, Kasri A, Rivals I, Goh P, Faklaris O, Cossec JC, Morel E, Rebillat AS, Nizetic D, Raposo G, Potier MC. Ultrastructural and dynamic studies of the endosomal compartment in Down syndrome. Acta Neuropathol Commun 2020; 8:89. [PMID: 32580751 PMCID: PMC7315513 DOI: 10.1186/s40478-020-00956-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 05/27/2020] [Indexed: 12/17/2022] Open
Abstract
Enlarged early endosomes have been visualized in Alzheimer's disease (AD) and Down syndrome (DS) using conventional confocal microscopy at a resolution corresponding to endosomal size (hundreds of nm). In order to overtake the diffraction limit, we used super-resolution structured illumination microscopy (SR-SIM) and transmission electron microscopies (TEM) to analyze the early endosomal compartment in DS.By immunofluorescence and confocal microscopy, we confirmed that the volume of Early Endosome Antigen 1 (EEA1)-positive puncta was 13-19% larger in fibroblasts and iPSC-derived neurons from individuals with DS, and in basal forebrain cholinergic neurons (BFCN) of the Ts65Dn mice modelling DS. However, EEA1-positive structures imaged by TEM or SR-SIM after chemical fixation had a normal size but appeared clustered. In order to disentangle these discrepancies, we imaged optimally preserved High Pressure Freezing (HPF)-vitrified DS fibroblasts by TEM and found that early endosomes were 75% denser but remained normal-sized.RNA sequencing of DS and euploid fibroblasts revealed a subgroup of differentially-expressed genes related to cargo sorting at multivesicular bodies (MVBs). We thus studied the dynamics of endocytosis, recycling and MVB-dependent degradation in DS fibroblasts. We found no change in endocytosis, increased recycling and delayed degradation, suggesting a "traffic jam" in the endosomal compartment.Finally, we show that the phosphoinositide PI (3) P, involved in early endosome fusion, is decreased in DS fibroblasts, unveiling a new mechanism for endosomal dysfunctions in DS and a target for pharmacotherapy.
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Affiliation(s)
- Alexandra Botté
- Paris Brain Institute (ICM), CNRS UMR7225, INSERM U1127, Sorbonne Université, Hôpital de la Pitié-Salpêtrière, Paris, France
| | - Jeanne Lainé
- Paris Brain Institute (ICM), CNRS UMR7225, INSERM U1127, Sorbonne Université, Hôpital de la Pitié-Salpêtrière, Paris, France
- Sorbonne Université, Département de Physiologie, Hôpital de la Pitié-Salpêtrière, Paris, France
| | - Laura Xicota
- Paris Brain Institute (ICM), CNRS UMR7225, INSERM U1127, Sorbonne Université, Hôpital de la Pitié-Salpêtrière, Paris, France
| | - Xavier Heiligenstein
- CryoCapCell, 155 Bd de l’hôpital, 75013 Paris, France
- Institut Curie, PSL Research University, CNRS, UMR144, Structure and Membrane Compartments, Paris, France
| | - Gaëlle Fontaine
- Paris Brain Institute (ICM), CNRS UMR7225, INSERM U1127, Sorbonne Université, Hôpital de la Pitié-Salpêtrière, Paris, France
| | - Amal Kasri
- Paris Brain Institute (ICM), CNRS UMR7225, INSERM U1127, Sorbonne Université, Hôpital de la Pitié-Salpêtrière, Paris, France
| | - Isabelle Rivals
- Equipe de Statistique Appliquée, ESPCI Paris, PSL Research University, UMRS 1158, Paris, France
| | - Pollyanna Goh
- The Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary, University of London, London, UK
| | - Orestis Faklaris
- ImagoSeine Imaging Core Facility, Institut Jacques Monod, CNRS UMR7592, Université Paris-Diderot, Sorbonne Paris Cité, Paris, France
| | - Jack-Christophe Cossec
- Paris Brain Institute (ICM), CNRS UMR7225, INSERM U1127, Sorbonne Université, Hôpital de la Pitié-Salpêtrière, Paris, France
| | - Etienne Morel
- Institut Necker-Enfants Malades (INEM), INSERM U1151 CNRS UMR 8253, Université Paris Descartes-Sorbonne Paris Cité, Paris, France
| | | | - Dean Nizetic
- The Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary, University of London, London, UK
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Graça Raposo
- Institut Curie, PSL Research University, CNRS, UMR144, Structure and Membrane Compartments, Paris, France
| | - Marie-Claude Potier
- Paris Brain Institute (ICM), CNRS UMR7225, INSERM U1127, Sorbonne Université, Hôpital de la Pitié-Salpêtrière, Paris, France
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Han J, Goldstein LA, Hou W, Watkins SC, Rabinowich H. Involvement of CASP9 (caspase 9) in IGF2R/CI-MPR endosomal transport. Autophagy 2020; 17:1393-1409. [PMID: 32397873 DOI: 10.1080/15548627.2020.1761742] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Recently, we reported that increased expression of CASP9 pro-domain, at the endosomal membrane in response to HSP90 inhibition, mediates a cell-protective effect that does not involve CASP9 apoptotic activity. We report here that a non-apoptotic activity of endosomal membrane CASP9 facilitates the retrograde transport of IGF2R/CI-MPR from the endosomes to the trans-Golgi network, indicating the involvement of CASP9 in endosomal sorting and lysosomal biogenesis. CASP9-deficient cells demonstrate the missorting of CTSD (cathepsin D) and other acid hydrolases, accumulation of late endosomes, and reduced degradation of bafilomycin A1-sensitive proteins. In the absence of CASP9, IGF2R undergoes significant degradation, and its rescue is achieved by the re-expression of a non-catalytic CASP9 mutant. This endosomal activity of CASP9 is potentially mediated by herein newly identified interactions of CASP9 with the components of the endosomal membrane transport complexes. These endosomal complexes include the retromer VPS35 and the SNX dimers, SNX1-SNX5 and SNX2-SNX6, which are involved in the IGF2R retrieval mechanism. Additionally, CASP9 interacts with HGS/HRS/ESCRT-0 and the CLTC (clathrin heavy chain) that participate in the initiation of the endosomal ESCRT degradation pathway. We propose that endosomal CASP9 inhibits the endosomal membrane degradative subdomain(s) from initiating the ESCRT-mediated degradation of IGF2R, allowing its retrieval to transport-designated endosomal membrane subdomain(s). These findings are the first to identify a cell survival, non-apoptotic function for CASP9 at the endosomal membrane, a site distinctly removed from the cytoplasmic apoptosome. Via its non-apoptotic endosomal function, CASP9 impacts the retrograde transport of IGF2R and, consequently, lysosomal biogenesis.Abbreviations: ACTB: actin beta; ATG7: autophagy related 7; BafA1: bafilomycin A1; CASP: caspase; CLTC/CHC: clathrin, heavy chain; CTSD: cathepsin D; ESCRT: endosomal sorting complexes required for transport; HEXB: hexosaminidase subunit beta; HGS/HRS/ESCRT-0: hepatocyte growth factor-regulated tyrosine kinase substrate; IGF2R/CI-MPR: insulin like growth factor 2 receptor; ILV: intraluminal vesicles; KD: knockdown; KO: knockout; M6PR/CD-MPR: mannose-6-phosphate receptor, cation dependent; MEF: murine embryonic fibroblasts; MWU: Mann-Whitney U test; PepA: pepstatin A; RAB7A: RAB7, member RAS oncogene family; SNX-BAR: sorting nexin dimers with a Bin/Amphiphysin/Rvs (BAR) domain each; TGN: trans-Golgi network; TUBB: tubulin beta; VPS26: VPS26 retromer complex component; VPS29: VPS29 retromer complex component; VPS35: VPS35 retromer complex component.
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Affiliation(s)
- Jie Han
- Departments of Pathology, University of Pittsburgh School of Medicine and the University of Pittsburgh Cancer Institute, Pittsburgh, PA, USA
| | - Leslie A Goldstein
- Departments of Pathology, University of Pittsburgh School of Medicine and the University of Pittsburgh Cancer Institute, Pittsburgh, PA, USA
| | - Wen Hou
- Departments of Pathology, University of Pittsburgh School of Medicine and the University of Pittsburgh Cancer Institute, Pittsburgh, PA, USA
| | - Simon C Watkins
- Cell Biology, University of Pittsburgh School of Medicine and the University of Pittsburgh Cancer Institute, Pittsburgh, PA, USA
| | - Hannah Rabinowich
- Departments of Pathology, University of Pittsburgh School of Medicine and the University of Pittsburgh Cancer Institute, Pittsburgh, PA, USA
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Teng F, Fussenegger M. Shedding Light on Extracellular Vesicle Biogenesis and Bioengineering. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2020; 8:2003505. [PMID: 33437589 PMCID: PMC7788585 DOI: 10.1002/advs.202003505] [Citation(s) in RCA: 179] [Impact Index Per Article: 44.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 10/16/2020] [Indexed: 05/14/2023]
Abstract
Extracellular vesicles (EVs) are biocompatible, nano-sized secreted vesicles containing many types of biomolecules, including proteins, RNAs, DNAs, lipids, and metabolites. Their low immunogenicity and ability to functionally modify recipient cells by transferring diverse bioactive constituents make them an excellent candidate for a next-generation drug delivery system. Here, the recent advances in EV biology and emerging strategies of EV bioengineering are summarized, and the prospects for clinical translation of bioengineered EVs and the challenges to be overcome are discussed.
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Affiliation(s)
- Fei Teng
- Department of Biosystems Science and EngineeringETH ZurichMattenstrasse 26BaselCH‐4058Switzerland
| | - Martin Fussenegger
- Department of Biosystems Science and EngineeringETH ZurichMattenstrasse 26BaselCH‐4058Switzerland
- Faculty of ScienceUniversity of BaselMattenstrasse 26BaselCH‐4058Switzerland
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Abstract
Cellular membranes can form two principally different involutions, which either exclude or contain cytosol. The 'classical' budding reactions, such as those occurring during endocytosis or formation of exocytic vesicles, involve proteins that assemble on the cytosol-excluding face of the bud neck. Inverse membrane involution occurs in a wide range of cellular processes, supporting cytokinesis, endosome maturation, autophagy, membrane repair and many other processes. Such inverse membrane remodelling is mediated by a heteromultimeric protein machinery known as endosomal sorting complex required for transport (ESCRT). ESCRT proteins assemble on the cytosolic (or nucleoplasmic) face of the neck of the forming involution and cooperate with the ATPase VPS4 to drive membrane scission or sealing. Here, we review similarities and differences of various ESCRT-dependent processes, with special emphasis on mechanisms of ESCRT recruitment.
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32
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Saffi GT, Botelho RJ. Lysosome Fission: Planning for an Exit. Trends Cell Biol 2019; 29:635-646. [PMID: 31171420 DOI: 10.1016/j.tcb.2019.05.003] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Revised: 05/01/2019] [Accepted: 05/03/2019] [Indexed: 01/26/2023]
Abstract
Lysosomes are acidic and degradative organelles that receive and digest a plethora of molecular and particulate cargo delivered by endocytosis, autophagy, and phagocytosis. The mechanisms responsible for sorting, transporting, and ultimately delivering membranes and cargo to lysosomes through fusion have been intensely investigated. Much less is understood about lysosome fission, which is necessary to balance the incessant flow of cargo into lysosomes and maintain steady-state number, size, and function of lysosomes. Here, we review the emerging picture of how lipid signals, coat and adaptor proteins, and motor-cytoskeletal assemblies drive budding, tubulation, splitting, and 'kiss-and-run' events that enable fission and exit from lysosomes and related organelles.
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Affiliation(s)
- Golam T Saffi
- Department of Chemistry and Biology and the Molecular Science Graduate Program, Ryerson University, Toronto, ONT, M5B2K3, Canada
| | - Roberto J Botelho
- Department of Chemistry and Biology and the Molecular Science Graduate Program, Ryerson University, Toronto, ONT, M5B2K3, Canada.
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Song Q, Yi F, Zhang Y, Jun Li DK, Wei Y, Yu H, Zhang Y. CRKL regulates alternative splicing of cancer-related genes in cervical cancer samples and HeLa cell. BMC Cancer 2019; 19:499. [PMID: 31133010 PMCID: PMC6537309 DOI: 10.1186/s12885-019-5671-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 05/02/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Aberrant spliced isoforms are specifically associated with cancer progression and metastasis. The cytoplasmic adaptor CRKL (v-crk avian sarcoma virus CT10 oncogene homolog-like) is a CRK like proto-oncogene, which encodes a SH2 and SH3 (src homology) domain-containing adaptor protein. CRKL is tightly linked to leukemia via its binding partners BCR-ABL and TEL-ABL, upregulated in multiple types of human cancers, and induce cancer cell proliferation and invasion. However, it remains unclear whether signaling adaptors such as CRKL could regulate alternative splicing. METHODS We analyzed the expression level of CRKL in 305 cervical cancer tissue samples available in TCGA database, and then selected two groups of cancer samples with CRKL differentially expressed to analyzed potential CRKL-regulated alternative splicing events (ASEs). CRKL was knocked down by shRNA to further study CRKL-regulated alternative splicing and the activity of SR protein kinases in HeLa cells using RNA-Seq and Western blot techniques. We validated 43 CRKL-regulated ASEs detected by RNA-seq in HeLa cells, using RT-qPCR analysis of HeLa cell samples and using RNA-seq data of the two group of clinical cervical samples. RESULTS The expression of CRKL was mostly up-regulated in stage I cervical cancer samples. Knock-down of CRKL led to a reduced cell proliferation. CRKL-regulated alternative splicing of a large number of genes were enriched in cancer-related functional pathways, among which DNA repair and G2/M mitotic cell cycle, GnRH signaling were shared among the top 10 enriched GO terms and KEGG pathways by results from clinical samples and HeLa cell model. We showed that CRKL-regulated ASEs revealed by computational analysis using ABLas software in HeLa cell were highly validated by RT-qPCR, and also validated by cervical cancer clinical samples. CONCLUSIONS This is the first report of CRKL-regulation of the alternative splicing of a number of genes critical in tumorigenesis and cancer progression, which is consistent with CRKL reported role as a signaling adaptor and a kinase. Our results underline that the signaling adaptor CRKL might integrate the external and intrinsic cellular signals and coordinate the dynamic activation of cellular signaling pathways including alternative splicing regulation.
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Affiliation(s)
- Qingling Song
- Department of Oncology and Radiotherapy, Wuhan General Hospital of Guangzhou Military Command, Wuhan, 430070, Hubei Province, China
| | - Fengtao Yi
- Department of Oncology and Radiotherapy, Wuhan General Hospital of Guangzhou Military Command, Wuhan, 430070, Hubei Province, China.
| | - Yuhong Zhang
- Laboratory of Human Health and Genome Regulation, Wuhan, 430075, Hubei, China.,Center for Genome Analysis, ABLife Inc, Wuhan, 430075, Hubei, China
| | - Daniel K Jun Li
- Center for Genome Analysis, ABLife Inc, Wuhan, 430075, Hubei, China.,Department of Biology and Biotechnology, School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, Wuhan, 430070, Hubei, China
| | - Yaxun Wei
- Center for Genome Analysis, ABLife Inc, Wuhan, 430075, Hubei, China
| | - Han Yu
- Laboratory of Human Health and Genome Regulation, Wuhan, 430075, Hubei, China
| | - Yi Zhang
- Laboratory of Human Health and Genome Regulation, Wuhan, 430075, Hubei, China. .,Center for Genome Analysis, ABLife Inc, Wuhan, 430075, Hubei, China.
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Hasegawa J, Imen J, Yamamoto H, Tsujita K, Tokuda E, Shibata H, Maki M, Itoh T. SH3YL1 cooperates with ESCRT-I in the sorting and degradation of the EGF receptor. J Cell Sci 2019; 132:jcs.229179. [DOI: 10.1242/jcs.229179] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 08/29/2019] [Indexed: 12/12/2022] Open
Abstract
Ubiquitinated membrane proteins such as epidermal growth factor receptor (EGFR) are delivered to early endosomes and then sorted to lysosomes via multivesicular bodies (MVBs) for degradation. The regulatory mechanism underlying formation of intralumenal vesicles en route to generation of MVBs is not fully understood. In this study, we found that SH3YL1, a phosphoinositide-binding protein, had a vesicular localization pattern overlapping with internalized EGF in endosomes in the degradative pathway. Deficiency of SH3YL1 prevents EGF trafficking from early to late endosomes and inhibits degradation of EGFR. Moreover, we show that SH3YL1 mediates EGFR sorting into MVBs in a manner dependent on its carboxy-terminal SH3 domain, which is necessary for the interaction with an ESCRT-I component, Vps37B. Taken together, our observations reveal an indispensable role of SH3YL1 in MVB-sorting and EGFR degradation mediated by ESCRT complexes.
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Affiliation(s)
- Junya Hasegawa
- Division of Membrane Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017, Japan
| | - Jebri Imen
- Division of Membrane Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017, Japan
- Biosignal Research Center, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan
| | - Hikaru Yamamoto
- Biosignal Research Center, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan
| | - Kazuya Tsujita
- Division of Membrane Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017, Japan
- Biosignal Research Center, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan
| | - Emi Tokuda
- Integrated Center for Mass Spectrometry, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017, Japan
| | - Hideki Shibata
- Department of Applied Biosciences, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
| | - Masatoshi Maki
- Department of Applied Biosciences, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan
| | - Toshiki Itoh
- Division of Membrane Biology, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, Hyogo 650-0017, Japan
- Biosignal Research Center, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, Hyogo 657-8501, Japan
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Cullen PJ, Steinberg F. To degrade or not to degrade: mechanisms and significance of endocytic recycling. Nat Rev Mol Cell Biol 2018; 19:679-696. [PMID: 30194414 DOI: 10.1038/s41580-018-0053-7] [Citation(s) in RCA: 293] [Impact Index Per Article: 48.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Newly endocytosed integral cell surface proteins are typically either directed for degradation or subjected to recycling back to the plasma membrane. The sorting of integral cell surface proteins, including signalling receptors, nutrient transporters, ion channels, adhesion molecules and polarity markers, within the endolysosomal network for recycling is increasingly recognized as an essential feature in regulating the complexities of physiology at the cell, tissue and organism levels. Historically, endocytic recycling has been regarded as a relatively passive process, where the majority of internalized integral proteins are recycled via a nonspecific sequence-independent 'bulk membrane flow' pathway. Recent work has increasingly challenged this view. The discovery of sequence-specific sorting motifs and the identification of cargo adaptors and associated coat complexes have begun to uncover the highly orchestrated nature of endosomal cargo recycling, thereby providing new insight into the function and (patho)physiology of this process.
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Affiliation(s)
- Peter J Cullen
- School of Biochemistry, Biomedical Sciences Building, University of Bristol, Bristol, UK.
| | - Florian Steinberg
- Center for Biological Systems Analysis, Albert Ludwigs Universitaet Freiburg, Freiburg im Breisgau, Germany.
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Roles for ER:endosome membrane contact sites in ligand-stimulated intraluminal vesicle formation. Biochem Soc Trans 2018; 46:1055-1062. [PMID: 30242114 PMCID: PMC6195632 DOI: 10.1042/bst20170432] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 07/31/2018] [Accepted: 08/08/2018] [Indexed: 12/12/2022]
Abstract
Multivesicular endosomes/bodies (MVBs) sort membrane proteins between recycling and degradative pathways. Segregation of membrane proteins onto intraluminal vesicles (ILVs) of MVBs removes them from the recycling pathway and facilitates their degradation following fusion of MVBs with lysosomes. Sorting of many cargos onto ILVs depends on the ESCRT (Endosomal Sorting Complex Required for Transport) machinery, although ESCRT-independent mechanisms also exist. In mammalian cells, efficient sorting of ligand-stimulated epidermal growth factor receptors onto ILVs also depends on the tyrosine phosphatase, PTP1B, an ER-localised enzyme that interacts with endosomal targets at membrane contacts between MVBs and the ER. This review focuses on the potential roles played by ER:MVB membrane contact sites in regulating ESCRT-dependent ILV formation.
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DeLeo AM, Ikezu T. Extracellular Vesicle Biology in Alzheimer's Disease and Related Tauopathy. J Neuroimmune Pharmacol 2018; 13:292-308. [PMID: 29185187 PMCID: PMC5972041 DOI: 10.1007/s11481-017-9768-z] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Accepted: 10/23/2017] [Indexed: 12/14/2022]
Abstract
Extracellular vesicles (EVs) are physiological vesicles secreted from most eukaryotes and contain cargos of their cell of origin. EVs, and particularly a subset of EV known as exosomes, are emerging as key mediators of cell to cell communication and waste management for cells both during normal organismal function and in disease. In this review, we investigate the rapidly growing field of exosome biology, their biogenesis, cargo loading, and uptake by other cells. We particularly consider the role of exosomes in Alzheimer's disease, both as a pathogenic agent and as a disease biomarker. We also explore the emerging role of exosomes in chronic traumatic encephalopathy. Finally, we highlight open questions in these fields and the possible use of exosomes as therapeutic targets and agents.
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Affiliation(s)
- Annina M DeLeo
- Laboratory of Molecular NeuroTherapeutics, Department of Pharmacology & Experimental Therapeutics, Boston University School of Medicine, 72 East Concord St, L-606, Boston, MA, 02118, USA.
| | - Tsuneya Ikezu
- Laboratory of Molecular NeuroTherapeutics, Department of Pharmacology & Experimental Therapeutics, Boston University School of Medicine, 72 East Concord St, L-606, Boston, MA, 02118, USA.
- Department of Neurology, Boston University School of Medicine, Boston, MA, 02118, USA.
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38
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Endosomal Retrieval of Cargo: Retromer Is Not Alone. Trends Cell Biol 2018; 28:807-822. [PMID: 30072228 DOI: 10.1016/j.tcb.2018.06.005] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 06/15/2018] [Accepted: 06/22/2018] [Indexed: 11/20/2022]
Abstract
Endosomes are major protein sorting stations in cells. Endosomally localised multi-protein complexes sort integral proteins, including signaling receptors, nutrient transporters, adhesion molecules, and lysosomal hydrolase receptors, for lysosomal degradation or conversely for retrieval and subsequent recycling to various membrane compartments. Correct endosomal sorting of these proteins is essential for maintaining cellular homeostasis, with defects in endosomal sorting implicated in various human pathologies including neurodegenerative disorders. Retromer, an ancient multi-protein complex, is essential for the retrieval and recycling of hundreds of transmembrane proteins. While retromer is a major player in endosomal retrieval and recycling, several studies have recently identified retrieval mechanisms that are independent of retromer. Here, we review endosomal retrieval complexes, with a focus on recently discovered retromer-independent mechanisms.
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Concerted ESCRT and clathrin recruitment waves define the timing and morphology of intraluminal vesicle formation. Nat Commun 2018; 9:2932. [PMID: 30050131 PMCID: PMC6062606 DOI: 10.1038/s41467-018-05345-8] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2017] [Accepted: 06/29/2018] [Indexed: 01/09/2023] Open
Abstract
The endosomal sorting complex required for transport (ESCRT) machinery mediates cargo sorting, membrane deformation and membrane scission on the surface of endosomes, generating intraluminal vesicles (ILVs) to degrade signaling receptors. By live-cell imaging of individual endosomes in human cells, we find that ESCRT proteins are recruited in a repetitive pattern: ESCRT-0 and -I show a gradual and linear recruitment and dissociation, whereas ESCRT-III and its regulatory ATPase VPS4 display fast and transient dynamics. Electron microscopy shows that ILVs are formed consecutively, starting immediately after endocytic uptake of cargo proteins and correlating with the repeated ESCRT recruitment waves, unraveling the timing of ILV formation. Clathrin, recruited by ESCRT-0, is required for timely ESCRT-0 dissociation, efficient ILV formation, correct ILV size and cargo degradation. Thus, cargo sorting and ILV formation occur by concerted, coordinated and repetitive recruitment waves of individual ESCRT subcomplexes and are controlled by clathrin. Intraluminal vesicles are formed by the endosomal sorting complex required for transport (ESCRT) machinery. Here, the authors unravel the timing of vesicle budding, and that endosomal clathrin regulates concerted recruitment of ESCRT subcomplexes, required for efficient membrane remodeling.
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40
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Zhang J, Liu J, Norris A, Grant BD, Wang X. A novel requirement for ubiquitin-conjugating enzyme UBC-13 in retrograde recycling of MIG-14/Wntless and Wnt signaling. Mol Biol Cell 2018; 29:2098-2112. [PMID: 29927348 PMCID: PMC6232959 DOI: 10.1091/mbc.e17-11-0639] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
After endocytosis, transmembrane cargoes such as signaling receptors, channels, and transporters enter endosomes where they are sorted to different destinations. Retromer and ESCRT (endosomal sorting complex required for transport) are functionally distinct protein complexes on endosomes that direct cargo sorting into the recycling retrograde transport pathway and the degradative multivesicular endosome pathway (MVE), respectively. Cargoes destined for degradation in lysosomes are decorated with K63-linked ubiquitin chains, which serve as an efficient sorting signal for entry into the MVE pathway. Defects in K63-linked ubiquitination disrupt MVE sorting and degradation of membrane proteins. Here, we unexpectedly found that UBC-13, the E2 ubiquitin-conjugating enzyme that generates K63-linked ubiquitin chains, is essential for retrograde transport of multiple retromer-dependent cargoes including MIG-14/Wntless. Loss of ubc-13 disrupts MIG-14/Wntless trafficking from endosomes to the Golgi, causing missorting of MIG-14 to lysosomes and impairment of Wnt-dependent processes. We observed that retromer-associated SNX-1 and the ESCRT-0 subunit HGRS-1/Hrs localized to distinct regions on a common endosome in wild type but overlapped on ubc-13(lf) endosomes, indicating that UBC-13 is important for the separation of retromer and ESCRT microdomains on endosomes. Our data suggest that cargo ubiquitination mediated by UBC-13 plays an important role in maintaining the functionally distinct subdomains to ensure efficient cargo segregation on endosomes.
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Affiliation(s)
- Junbing Zhang
- College of Life Science, Beijing Normal University, Beijing 100875, China.,National Institute of Biological Sciences, Beijing 102206, China.,National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Jinchao Liu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Anne Norris
- Department of Molecular Biology and Biochemistry, Rutgers University, Piscataway, NJ 08854
| | - Barth D Grant
- Department of Molecular Biology and Biochemistry, Rutgers University, Piscataway, NJ 08854
| | - Xiaochen Wang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.,College of Life Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
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41
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To be or not to be... secreted as exosomes, a balance finely tuned by the mechanisms of biogenesis. Essays Biochem 2018; 62:177-191. [PMID: 29717057 DOI: 10.1042/ebc20170076] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 02/27/2018] [Accepted: 03/06/2018] [Indexed: 12/19/2022]
Abstract
The release of extracellular vesicles such as exosomes provides an attractive intercellular communication pathway. Exosomes are 30- to 150-nm membrane vesicles that are generated in endosomal compartment and act as intercellular mediators in both physiological and pathological context. Despite the growing interest in exosome functions, the mechanisms responsible for their biogenesis and secretion are still not completely understood. Knowledge about these mechanisms is important because they control the composition, and hence the function and secretion, of exosomes. Exosomes are produced as intraluminal vesicles in extremely dynamic endosomal organelles, which undergo various maturation processes in order to form multivesicular endosomes. Notably, the function of multivesicular endosomes is balanced between exosome secretion and lysosomal degradation. In the present review, we present and discuss each intracellular trafficking pathway that has been reported or proposed as regulating exosome biogenesis, with a particular focus on the importance of endosomal dynamics in sorting out cargo proteins to exosomes and to the secretion of multivesicular endosomes. An overall picture reveals several key mechanisms, which mainly act at the crossroads of endosomal pathways as regulatory checkpoints of exosome biogenesis.
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42
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Endosomal binding kinetics of Eps15 and Hrs specifically regulate the degradation of RTKs. Sci Rep 2017; 7:17962. [PMID: 29269784 PMCID: PMC5740074 DOI: 10.1038/s41598-017-17320-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 10/25/2017] [Indexed: 01/25/2023] Open
Abstract
Activation of EGF-R and PDGF-R triggers autophosphorylation and the recruitment of Eps15 and Hrs. These two endosomal proteins are important for specific receptor sorting. Hrs is recruiting ubiquitinated receptors to early endosomes to further facilitate degradation through the ESCRT complex. Upon receptor activation Hrs becomes phosphorylated and is relocated to the cytosol, important for receptor degradation. In this work we have studied the endosomal binding dynamics of Eps15 and Hrs upon EGF-R and PDGF-R stimulation. By analysing the fluorescence intensity on single endosomes after ligand stimulation we measured a time-specific decrease in the endosomal fluorescence level of Eps15-GFP and Hrs-YFP. Through FRAP experiments we could further register a specific change in the endosomal-membrane to cytosol binding properties of Eps15-GFP and Hrs-YFP. This specific change in membrane fractions proved to be a redistribution of the immobile fraction, which was not shown for the phosphorylation deficient mutants. We here describe a mechanism that can explain the previously observed relocation of Hrs from the endosomes to cytosol after EGF stimulation and show that Eps15 follows a similar mechanism. Moreover, this specific redistribution of the endosomal protein binding dynamics proved to be of major importance for receptor degradation.
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43
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Nagel MK, Kalinowska K, Vogel K, Reynolds GD, Wu Z, Anzenberger F, Ichikawa M, Tsutsumi C, Sato MH, Kuster B, Bednarek SY, Isono E. Arabidopsis SH3P2 is an ubiquitin-binding protein that functions together with ESCRT-I and the deubiquitylating enzyme AMSH3. Proc Natl Acad Sci U S A 2017; 114:E7197-E7204. [PMID: 28784794 PMCID: PMC5576839 DOI: 10.1073/pnas.1710866114] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Clathrin-mediated endocytosis of plasma membrane proteins is an essential regulatory process that controls plasma membrane protein abundance and is therefore important for many signaling pathways, such as hormone signaling and biotic and abiotic stress responses. On endosomal sorting, plasma membrane proteins maybe recycled or targeted for vacuolar degradation, which is dependent on ubiquitin modification of the cargos and is driven by the endosomal sorting complexes required for transport (ESCRTs). Components of the ESCRT machinery are highly conserved among eukaryotes, but homologs of ESCRT-0 that are responsible for recognition and concentration of ubiquitylated proteins are absent in plants. Recently several ubiquitin-binding proteins have been identified that serve in place of ESCRT-0; however, their function in ubiquitin recognition and endosomal trafficking is not well understood yet. In this study, we identified Src homology-3 (SH3) domain-containing protein 2 (SH3P2) as a ubiquitin- and ESCRT-I-binding protein that functions in intracellular trafficking. SH3P2 colocalized with clathrin light chain-labeled punctate structures and interacted with clathrin heavy chain in planta, indicating a role for SH3P2 in clathrin-mediated endocytosis. Furthermore, SH3P2 cofractionates with clathrin-coated vesicles (CCVs), suggesting that it associates with CCVs in planta Mutants of SH3P2 and VPS23 genetically interact, suggesting that they could function in the same pathway. Based on these results, we suggest a role of SH3P2 as an ubiquitin-binding protein that binds and transfers ubiquitylated proteins to the ESCRT machinery.
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Affiliation(s)
- Marie-Kristin Nagel
- Chair of Plant Physiology and Biochemistry, Department of Biology, University of Konstanz, 78457 Konstanz, Germany
- Chair of Plant Systems Biology, School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising, Germany
| | - Kamila Kalinowska
- Chair of Plant Systems Biology, School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising, Germany
| | - Karin Vogel
- Chair of Plant Physiology and Biochemistry, Department of Biology, University of Konstanz, 78457 Konstanz, Germany
- Chair of Plant Systems Biology, School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising, Germany
| | - Gregory D Reynolds
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706
| | - Zhixiang Wu
- Chair of Proteomics and Bioanalytics, School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising, Germany
| | - Franziska Anzenberger
- Chair of Plant Systems Biology, School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising, Germany
| | - Mie Ichikawa
- Department of Life and Environmental Sciences, Kyoto Prefectural University, 606-0823 Kyoto, Japan
| | - Chie Tsutsumi
- Department of Botany, National Museum of Nature and Science, 305-0005 Tsukuba, Japan
| | - Masa H Sato
- Department of Life and Environmental Sciences, Kyoto Prefectural University, 606-0823 Kyoto, Japan
| | - Bernhard Kuster
- Chair of Proteomics and Bioanalytics, School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising, Germany
| | | | - Erika Isono
- Chair of Plant Physiology and Biochemistry, Department of Biology, University of Konstanz, 78457 Konstanz, Germany;
- Chair of Plant Systems Biology, School of Life Sciences Weihenstephan, Technical University of Munich, 85354 Freising, Germany
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44
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Meister M, Bänfer S, Gärtner U, Koskimies J, Amaddii M, Jacob R, Tikkanen R. Regulation of cargo transfer between ESCRT-0 and ESCRT-I complexes by flotillin-1 during endosomal sorting of ubiquitinated cargo. Oncogenesis 2017; 6:e344. [PMID: 28581508 PMCID: PMC5519196 DOI: 10.1038/oncsis.2017.47] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 04/02/2017] [Accepted: 05/02/2017] [Indexed: 01/02/2023] Open
Abstract
Ubiquitin-dependent sorting of membrane proteins in endosomes directs them to lysosomal degradation. In the case of receptors such as the epidermal growth factor receptor (EGFR), lysosomal degradation is important for the regulation of downstream signalling. Ubiquitinated proteins are recognised in endosomes by the endosomal sorting complexes required for transport (ESCRT) complexes, which sequentially interact with the ubiquitinated cargo. Although the role of each ESCRT complex in sorting is well established, it is not clear how the cargo is passed on from one ESCRT to the next. We here show that flotillin-1 is required for EGFR degradation, and that it interacts with the subunits of ESCRT-0 and -I complexes (hepatocyte growth factor-regulated tyrosine kinase substrate (Hrs) and Tsg101). Flotillin-1 is required for cargo recognition and sorting by ESCRT-0/Hrs and for its interaction with Tsg101. In addition, flotillin-1 is also required for the sorting of human immunodeficiency virus 1 Gag polyprotein, which mimics ESCRT-0 complex during viral assembly. We propose that flotillin-1 functions in cargo transfer between ESCRT-0 and -I complexes.
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Affiliation(s)
- M Meister
- Institute of Biochemistry, Medical Faculty, Justus-Liebig University of Giessen, Giessen, Germany
| | - S Bänfer
- Department of Cell Biology and Cell Pathology, Philipps University of Marburg, Marburg, Germany
| | - U Gärtner
- Institute of Anatomy and Cell Biology, Medical Faculty, Justus-Liebig University of Giessen, Giessen, Germany
| | - J Koskimies
- Institute of Biochemistry, Medical Faculty, Justus-Liebig University of Giessen, Giessen, Germany
| | - M Amaddii
- Institute of Biochemistry, Medical Faculty, Justus-Liebig University of Giessen, Giessen, Germany
| | - R Jacob
- Department of Cell Biology and Cell Pathology, Philipps University of Marburg, Marburg, Germany
| | - R Tikkanen
- Institute of Biochemistry, Medical Faculty, Justus-Liebig University of Giessen, Giessen, Germany
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45
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SNX-1 and RME-8 oppose the assembly of HGRS-1/ESCRT-0 degradative microdomains on endosomes. Proc Natl Acad Sci U S A 2017; 114:E307-E316. [PMID: 28053230 DOI: 10.1073/pnas.1612730114] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
After endocytosis, transmembrane cargo reaches endosomes, where it encounters complexes dedicated to opposing functions: recycling and degradation. Microdomains containing endosomal sorting complexes required for transport (ESCRT)-0 component Hrs [hepatocyte growth factor-regulated tyrosine kinase substrate (HGRS-1) in Caenorhabditis elegans] mediate cargo degradation, concentrating ubiquitinated cargo and organizing the activities of ESCRT. At the same time, retromer associated sorting nexin one (SNX-1) and its binding partner, J-domain protein RME-8, sort cargo away from degradation, promoting cargo recycling to the Golgi. Thus, we hypothesized that there could be important regulatory interactions between retromer and ESCRT that balance degradative and recycling functions. Taking advantage of the naturally large endosomes of the C. elegans coelomocyte, we visualized complementary ESCRT-0 and RME-8/SNX-1 microdomains in vivo and assayed the ability of retromer and ESCRT microdomains to regulate one another. We found in snx-1(0) and rme-8(ts) mutants increased endosomal coverage and intensity of HGRS-1-labeled microdomains, as well as increased total levels of HGRS-1 bound to membranes. These effects are specific to SNX-1 and RME-8, as loss of other retromer components SNX-3 and vacuolar protein sorting-associated protein 35 (VPS-35) did not affect HGRS-1 microdomains. Additionally, knockdown of hgrs-1 had little to no effect on SNX-1 and RME-8 microdomains, suggesting directionality to the interaction. Separation of the functionally distinct ESCRT-0 and SNX-1/RME-8 microdomains was also compromised in the absence of RME-8 and SNX-1, a phenomenon we observed to be conserved, as depletion of Snx1 and Snx2 in HeLa cells also led to greater overlap of Rme-8 and Hrs on endosomes.
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46
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Thomas P, Wohlford D, Aoh QL. SCAMP 3 is a novel regulator of endosomal morphology and composition. Biochem Biophys Res Commun 2016; 478:1028-34. [PMID: 27507217 DOI: 10.1016/j.bbrc.2016.08.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 08/03/2016] [Indexed: 12/15/2022]
Abstract
Secretory Carrier Membrane Proteins (SCAMPs) are transmembrane proteins that function in the plasma membrane, endosomes, and trans-Golgi network. Here we show that SCAMP 3 is a novel regulator of endosomal morphology and composition. Under certain nutrient-starved conditions, SCAMP 3 concentrates in enlarged early endosomes. The enlarged contain ubiquitylated and non-ubiquitylated SCAMP 3 as well as other SCAMPs, EEA1, and the ESCRT-0 protein Hrs. We demonstrate that SCAMP 3 is sufficient to recruit Hrs to the enlarged endosomes. Taken together, our results suggest a novel role for SCAMP 3 in modifying endosome structure through interactions that involve its ubiquitylation and ESCRT proteins.
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Affiliation(s)
- Priscilla Thomas
- Department of Biology, Gannon University, Erie, PA 16514, United States
| | - Dacey Wohlford
- Department of Biology, Gannon University, Erie, PA 16514, United States
| | - Quyen L Aoh
- Department of Biology, Gannon University, Erie, PA 16514, United States.
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47
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Abstract
In order to achieve coordinated growth and patterning during development, cells must communicate with one another, sending and receiving signals that regulate their activities. Such developmental signals can be soluble, bound to the extracellular matrix, or tethered to the surface of adjacent cells. Cells can also signal by releasing exosomes – extracellular vesicles containing bioactive molecules such as RNA, DNA and enzymes. Recent work has suggested that exosomes can also carry signalling proteins, including ligands of the Notch receptor and secreted proteins of the Hedgehog and WNT families. Here, we describe the various types of exosomes and their biogenesis. We then survey the experimental strategies used so far to interfere with exosome formation and critically assess the role of exosomes in developmental signalling.
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Affiliation(s)
- Ian John McGough
- Laboratory of Epithelial Interactions, The Francis Crick Institute, Mill Hill Laboratory, The Ridgeway, London NW7 1AA, UK
| | - Jean-Paul Vincent
- Laboratory of Epithelial Interactions, The Francis Crick Institute, Mill Hill Laboratory, The Ridgeway, London NW7 1AA, UK
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48
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Tian X, Irannejad R, Bowman SL, Du Y, Puthenveedu MA, von Zastrow M, Benovic JL. The α-Arrestin ARRDC3 Regulates the Endosomal Residence Time and Intracellular Signaling of the β2-Adrenergic Receptor. J Biol Chem 2016; 291:14510-25. [PMID: 27226565 DOI: 10.1074/jbc.m116.716589] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Indexed: 01/12/2023] Open
Abstract
Arrestin domain-containing protein 3 (ARRDC3) is a member of the mammalian α-arrestin family, which is predicted to share similar tertiary structure with visual-/β-arrestins and also contains C-terminal PPXY motifs that mediate interaction with E3 ubiquitin ligases. Recently, ARRDC3 has been proposed to play a role in regulating the trafficking of G protein-coupled receptors, although mechanistic insight into this process is lacking. Here, we focused on characterizing the role of ARRDC3 in regulating the trafficking of the β2-adrenergic receptor (β2AR). We find that ARRDC3 primarily localizes to EEA1-positive early endosomes and directly interacts with the β2AR in a ligand-independent manner. Although ARRDC3 has no effect on β2AR endocytosis or degradation, it negatively regulates β2AR entry into SNX27-occupied endosomal tubules. This results in delayed recycling of the receptor and a concomitant increase in β2AR-dependent endosomal signaling. Thus, ARRDC3 functions as a switch to modulate the endosomal residence time and subsequent intracellular signaling of the β2AR.
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Affiliation(s)
- Xufan Tian
- From the Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107
| | - Roshanak Irannejad
- the Department of Psychiatry, University of California at San Francisco, San Francisco, California 94158
| | - Shanna L Bowman
- the Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, and
| | - Yang Du
- the Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, California 94305
| | - Manojkumar A Puthenveedu
- the Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, and
| | - Mark von Zastrow
- the Department of Psychiatry, University of California at San Francisco, San Francisco, California 94158
| | - Jeffrey L Benovic
- From the Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107,
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49
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Schreij AMA, Fon EA, McPherson PS. Endocytic membrane trafficking and neurodegenerative disease. Cell Mol Life Sci 2016; 73:1529-45. [PMID: 26721251 PMCID: PMC11108351 DOI: 10.1007/s00018-015-2105-x] [Citation(s) in RCA: 105] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Revised: 10/26/2015] [Accepted: 11/26/2015] [Indexed: 12/11/2022]
Abstract
Neurodegenerative diseases are amongst the most devastating of human disorders. New technologies have led to a rapid increase in the identification of disease-related genes with an enhanced appreciation of the key roles played by genetics in the etiology of these disorders. Importantly, pinpointing the normal function of disease gene proteins leads to new understanding of the cellular machineries and pathways that are altered in the disease process. One such emerging pathway is membrane trafficking in the endosomal system. This key cellular process controls the localization and levels of a myriad of proteins and is thus critical for normal cell function. In this review we will focus on three neurodegenerative diseases; Parkinson disease, amyotrophic lateral sclerosis, and hereditary spastic paraplegias, for which a large number of newly discovered disease genes encode proteins that function in endosomal membrane trafficking. We will describe how alterations in these proteins affect endosomal function and speculate on the contributions of these disruptions to disease pathophysiology.
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Affiliation(s)
- Andrea M A Schreij
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, 3801 University Street, Montreal, QC, H3A 2B4, Canada
| | - Edward A Fon
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, 3801 University Street, Montreal, QC, H3A 2B4, Canada
| | - Peter S McPherson
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, 3801 University Street, Montreal, QC, H3A 2B4, Canada.
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50
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Salova AV, Belyaeva TN, Leontieva EA, Zlobina MV, Kharchenko MV, Kornilova ES. Quantum dots implementation as a label for analysis of early stages of EGF receptor endocytosis: a comparative study on cultured cells. Oncotarget 2016; 7:6029-47. [PMID: 26716513 PMCID: PMC4868738 DOI: 10.18632/oncotarget.6720] [Citation(s) in RCA: 8] [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: 07/28/2015] [Accepted: 11/25/2015] [Indexed: 12/16/2022] Open
Abstract
EGF complexed to fluorescent photostable quantum dots by biotin-streptavidin system (bEGF-savQD) is attractive for both the basic research and therapeutic application such as targeted drug delivery in EGF-receptor (EGFR) expressing cancers. However, compared to native EGF, the large size of QD and its quasi-multivalency can have unpredictable effects on EGFR endocytosis changing the internalization portal and/or endosomal processing tightly bound to EGF signaling. We have found that bEGF-savQDs enter HeLa cells via the temperature-dependent clathrin-mediated EGF-receptor-specific pathway characteristic for native EGF. We also found that EGF-to-QD concentration ratios used for the complex preparation and the level of EGF receptor expression affect the number and integral densities of the formed endosomes. So, at EGF-to-QD ratio from 4:1 to 12:1 (at nanomolar bEGF concentrations) on average 100 bright endosomes per HeLa cell were formed 15 min after the complex addition, while 1:1 ratio resulted in formation of very few dim endosomes. However, in A431 cells overexpressing EGFR 1:1 ratio was effective. Using dynamin inhibition and Na-acidic washout we showed that bEGF-savQDs bind surface receptors and enter clathrin-coated pits slower than the same ligands without QD. Yet, the bEGF-savQD demonstrated similar to native EGF and bEGF-savCy3 co-localization dynamics with tethering protein EEA1 and HRS, the key component of sorting ESCRT0 complex. In conclusion, our comparative study reveals that in respect to entrapment into coated pits, endosomal recruitment, endosome fusions, and the initial steps of endosomal maturation, bEGF-savQD behaves like native EGF and QD implementation does not affect these important events.
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Affiliation(s)
- Anna V. Salova
- Institute of Cytology of the Russian Academy of Sciences, St. Petersburg, Russia
| | - Tatiana N. Belyaeva
- Institute of Cytology of the Russian Academy of Sciences, St. Petersburg, Russia
| | | | - Maria V. Zlobina
- Institute of Cytology of the Russian Academy of Sciences, St. Petersburg, Russia
- Central European Institute of Technology, Brno, Czech Republic
| | | | - Elena S. Kornilova
- Institute of Cytology of the Russian Academy of Sciences, St. Petersburg, Russia
- Peter the Great St. Petersburg Polytechnic University, St. Petersburg, Russia
- St. Petersburg State University, St. Petersburg, Russia
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