301
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Gracida-Jiménez V, Mondragón-González R, Vélez-Aguilera G, Vásquez-Limeta A, Laredo-Cisneros MS, Gómez-López JDD, Vaca L, Gourlay SC, Jacobs LA, Winder SJ, Cisneros B. Retrograde trafficking of β-dystroglycan from the plasma membrane to the nucleus. Sci Rep 2017; 7:9906. [PMID: 28852008 PMCID: PMC5575308 DOI: 10.1038/s41598-017-09972-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Accepted: 07/31/2017] [Indexed: 12/04/2022] Open
Abstract
β-Dystroglycan (β-DG) is a transmembrane protein with critical roles in cell adhesion, cytoskeleton remodeling and nuclear architecture. This functional diversity is attributed to the ability of β-DG to target to, and conform specific protein assemblies at the plasma membrane (PM) and nuclear envelope (NE). Although a classical NLS and importin α/β mediated nuclear import pathway has already been described for β-DG, the intracellular trafficking route by which β-DG reaches the nucleus is unknown. In this study, we demonstrated that β-DG undergoes retrograde intracellular trafficking from the PM to the nucleus via the endosome-ER network. Furthermore, we provided evidence indicating that the translocon complex Sec61 mediates the release of β-DG from the ER membrane, making it accessible for importins and nuclear import. Finally, we show that phosphorylation of β-DG at Tyr890 is a key stimulus for β-DG nuclear translocation. Collectively our data describe the retrograde intracellular trafficking route that β-DG follows from PM to the nucleus. This dual role for a cell adhesion receptor permits the cell to functionally connect the PM with the nucleus and represents to our knowledge the first example of a cell adhesion receptor exhibiting retrograde nuclear trafficking and having dual roles in PM and NE.
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Affiliation(s)
- Viridiana Gracida-Jiménez
- Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Ciudad de México, Mexico, Mexico
| | - Ricardo Mondragón-González
- Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Ciudad de México, Mexico, Mexico
| | - Griselda Vélez-Aguilera
- Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Ciudad de México, Mexico, Mexico
| | - Alejandra Vásquez-Limeta
- Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Ciudad de México, Mexico, Mexico.,Laboratory of Protein Dynamics and Signaling, Center for Cancer Research-Frederick, National Cancer Institute, National Institutes of Health, Frederick, MD, 21702, USA
| | - Marco S Laredo-Cisneros
- Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Ciudad de México, Mexico, Mexico
| | - Juan de Dios Gómez-López
- Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Ciudad de México, Mexico, Mexico
| | - Luis Vaca
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de Mexico, Ciudad de Mexico, Mexico, Mexico
| | - Sarah C Gourlay
- Department of Biomedical Science, University of Sheffield, Western Bank, Sheffield, S10 2TN, United Kingdom
| | - Laura A Jacobs
- Department of Biomedical Science, University of Sheffield, Western Bank, Sheffield, S10 2TN, United Kingdom
| | - Steve J Winder
- Department of Biomedical Science, University of Sheffield, Western Bank, Sheffield, S10 2TN, United Kingdom
| | - Bulmaro Cisneros
- Departamento de Genética y Biología Molecular, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (CINVESTAV), Ciudad de México, Mexico, Mexico.
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302
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Van Ngo H, Bhalla M, Chen DY, Ireton K. A role for host cell exocytosis in InlB-mediated internalisation ofListeria monocytogenes. Cell Microbiol 2017; 19. [DOI: 10.1111/cmi.12768] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Revised: 07/10/2017] [Accepted: 07/24/2017] [Indexed: 12/17/2022]
Affiliation(s)
- Hoan Van Ngo
- Department of Microbiology and Immunology; University of Otago; Dunedin New Zealand
| | - Manmeet Bhalla
- Department of Microbiology and Immunology; University of Otago; Dunedin New Zealand
| | - Da-Yuan Chen
- Department of Microbiology and Immunology; University of Otago; Dunedin New Zealand
| | - Keith Ireton
- Department of Microbiology and Immunology; University of Otago; Dunedin New Zealand
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303
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Kraus F, Ryan MT. The constriction and scission machineries involved in mitochondrial fission. J Cell Sci 2017; 130:2953-2960. [PMID: 28842472 DOI: 10.1242/jcs.199562] [Citation(s) in RCA: 129] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
A key event in the evolution of eukaryotic cells was the engulfment of an aerobic bacterium by a larger anaerobic archaebacterium, leading to a close relationship between the host and the newly formed endosymbiont. Mitochondria, originating from this event, have evolved to be the main place of cellular ATP production. Maintaining elements of their independence, mitochondria undergo growth and division in the cell, thereby ensuring that new daughter cells inherit a mitochondrial complement. Mitochondrial division is also important for other processes, including quality control, mitochondrial (mt)DNA inheritance, transport and cell death. However, unlike bacterial fission, which uses a dynamin-related protein to constrict the membrane at its inner face, mitochondria use dynamin and dynamin-related proteins to constrict the outer membrane from the cytosolic face. In this Review, we summarize the role of proteins from the dynamin superfamily in mitochondrial division. This includes recent findings highlighting that dynamin-2 (Dnm2) is involved in mitochondrial scission, which led to the reappraisal of the role of dynamin-related protein 1 (Drp1; also known as Dnm1l) and its outer membrane adaptors as components of the mitochondrial constriction machinery along with ER components and actin.
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Affiliation(s)
- Felix Kraus
- Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, 3800 Melbourne, Australia
| | - Michael T Ryan
- Department of Biochemistry and Molecular Biology, Monash Biomedicine Discovery Institute, Monash University, 3800 Melbourne, Australia
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304
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Ramachandran R. Mitochondrial dynamics: The dynamin superfamily and execution by collusion. Semin Cell Dev Biol 2017; 76:201-212. [PMID: 28754444 DOI: 10.1016/j.semcdb.2017.07.039] [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] [Received: 06/17/2017] [Revised: 07/20/2017] [Accepted: 07/24/2017] [Indexed: 11/25/2022]
Abstract
Distinct dynamin superfamily GTPases catalyze the constant fission and fusion of the elaborate mitochondrial networks that navigate the eukaryotic cytoplasm. Long believed to be the singular handiwork of dynamin-related protein 1 (Drp1), a cytosolic family member that transiently localizes to the mitochondrial surface, the execution of mitochondrial fission is now arguably believed to entail membrane remodeling events that are initiated upstream of Drp1 by ER-associated cytoskeletal networks and completed downstream by the prototypical dynamin, dynamin 2 (Dyn2). Recent developments in the field have also placed a sharp focus on the membrane microenvironment around the division apparatus and the potential facilitatory role of specific lipids in mitochondrial fission. Here, I will review current progress, as well as highlight the most visible gaps in knowledge, in elucidating the varied functions of the dynamin superfamily in the coordinated events of mitochondrial fission and fusion. The essential roles of protein and lipid cofactors are also highlighted.
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Affiliation(s)
- Rajesh Ramachandran
- Department of Physiology & Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH, 44106-4970, USA.
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305
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Chiaruttini N, Roux A. Dynamic and elastic shape transitions in curved ESCRT-III filaments. Curr Opin Cell Biol 2017; 47:126-135. [PMID: 28728013 DOI: 10.1016/j.ceb.2017.07.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The ESCRT-III complex is an evolutionary ancient and conserved complex that catalyzes fission of lipid membranes from the lumen of the neck in many, if not all processes requiring this specific fission reaction. The ESCRT-III membrane remodeling complex is unique as its molecular and polymeric structures do not intuitively suggests how it could deform and break lipid membranes. Here we review the common structural features of the ESCRT-III subunits, and the shape diversity of the various filamentous forms. We propose a simple geometry and elasticity framework that could help to isolate which features of the ESCRT-III filaments are common to all filamentous forms as well as to explain their diversity. We speculate on how these features could provide mechanistic insights into the many functions of the ESCRT-III complex.
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Affiliation(s)
- Nicolas Chiaruttini
- Department of Biochemistry, University of Geneva, CH-1211 Geneva, Switzerland
| | - Aurélien Roux
- Department of Biochemistry, University of Geneva, CH-1211 Geneva, Switzerland; Swiss National Centre for Competence in Research Programme Chemical Biology, CH-1211 Geneva, Switzerland.
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306
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Schmid SL. Reciprocal regulation of signaling and endocytosis: Implications for the evolving cancer cell. J Cell Biol 2017; 216:2623-2632. [PMID: 28674108 PMCID: PMC5584184 DOI: 10.1083/jcb.201705017] [Citation(s) in RCA: 112] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 06/05/2017] [Accepted: 06/08/2017] [Indexed: 12/19/2022] Open
Abstract
Schmid provides a perspective on exciting new research examining the relationship between signaling and endocytosis in cancer. Cell surface receptor uptake via clathrin-mediated endocytosis (CME) and subsequent intracellular sorting for degradation or recycling regulates the strength and specificity of downstream signaling. Signaling, in turn, modulates early endocytic trafficking. This reciprocal regulation of signaling and endocytosis provides opportunities for the establishment of feedback loops to enhance or suppress surface-derived signals. Recent studies suggest that dynamin-1, a presumed neuron-specific isoform of the large, membrane fission GTPase, can be activated in nonneuronal cells downstream of cancer-relevant signaling pathways and thereby function as a nexus between signaling and early endocytic trafficking. I speculate that sustained up-regulation and/or acute activation of dynamin-1 in cancer cells contributes to a program of “adaptive” CME that alters signaling to enhance cancer cell survival, migration, and proliferation.
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Affiliation(s)
- Sandra L Schmid
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX
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307
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Abstract
Clostridium difficile is the cause of antibiotics-associated diarrhea and pseudomembranous colitis. The pathogen produces three protein toxins: C. difficile toxins A (TcdA) and B (TcdB), and C. difficile transferase toxin (CDT). The single-chain toxins TcdA and TcdB are the main virulence factors. They bind to cell membrane receptors and are internalized. The N-terminal glucosyltransferase and autoprotease domains of the toxins translocate from low-pH endosomes into the cytosol. After activation by inositol hexakisphosphate (InsP6), the autoprotease cleaves and releases the glucosyltransferase domain into the cytosol, where GTP-binding proteins of the Rho/Ras family are mono-O-glucosylated and, thereby, inactivated. Inactivation of Rho proteins disturbs the organization of the cytoskeleton and affects multiple Rho-dependent cellular processes, including loss of epithelial barrier functions, induction of apoptosis, and inflammation. CDT, the third C. difficile toxin, is a binary actin-ADP-ribosylating toxin that causes depolymerization of actin, thereby inducing formation of the microtubule-based protrusions. Recent progress in understanding of the toxins' actions include insights into the toxin structures, their interaction with host cells, and functional consequences of their actions.
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Affiliation(s)
- Klaus Aktories
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Freiburg, 79104 Freiburg, Germany; , ,
| | - Carsten Schwan
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Freiburg, 79104 Freiburg, Germany; , ,
| | - Thomas Jank
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Freiburg, 79104 Freiburg, Germany; , ,
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308
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Mold Alkaloid Cytochalasin D Modifies the Morphology and Secretion of fMLP-, LPS-, or PMA-Stimulated Neutrophils upon Adhesion to Fibronectin. Mediators Inflamm 2017; 2017:4308684. [PMID: 28740333 PMCID: PMC5504967 DOI: 10.1155/2017/4308684] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Revised: 04/11/2017] [Accepted: 04/27/2017] [Indexed: 12/15/2022] Open
Abstract
Neutrophils play an essential role in innate immunity due to their ability to migrate into infected tissues and kill microbes with bactericides located in their secretory granules. Neutrophil transmigration and degranulation are tightly regulated by actin cytoskeleton. Invading pathogens produce alkaloids that cause the depolymerization of actin, such as the mold alkaloid cytochalasin D. We studied the effect of cytochalasin D on the morphology and secretion of fMLP-, LPS-, or PMA-stimulated human neutrophils upon adhesion to fibronectin. Electron microscopy showed that the morphology of the neutrophils adherent to fibronectin in the presence of various stimuli differed. But in the presence of cytochalasin D, all stimulated neutrophils exhibited a uniform nonspread shape and developed thread-like membrane tubulovesicular extensions (cytonemes) measuring 200 nm in diameter. Simultaneous detection of neutrophil secretory products by mass spectrometry showed that all tested stimuli caused the secretion of MMP-9, a key enzyme in the neutrophil migration. Cytochalasin D impaired the MMP-9 secretion but initiated the release of cathepsin G and other granular bactericides, proinflammatory agents. The release of bactericides apparently occurs through the formation, shedding, and lysis of cytonemes. The production of alkaloids which modify neutrophil responses to stimulation via actin depolymerization may be part of the strategy of pathogen invasion.
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309
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Ince S, Kutsch M, Shydlovskyi S, Herrmann C. The human guanylate-binding proteins hGBP-1 and hGBP-5 cycle between monomers and dimers only. FEBS J 2017; 284:2284-2301. [PMID: 28580591 DOI: 10.1111/febs.14126] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 04/18/2017] [Accepted: 06/01/2017] [Indexed: 12/11/2022]
Abstract
Belonging to the dynamin superfamily of large GTPases, human guanylate-binding proteins (hGBPs) comprise a family of seven isoforms (hGBP-1 to hGBP-7) that are strongly upregulated in response to interferon-γ and other cytokines. Accordingly, several hGBPs are found to exhibit various cellular functions encompassing inhibitory effects on cell proliferation, tumor suppression as well as antiviral and antibacterial activity; however, their mechanism of action is only poorly understood. Often, cellular functions of dynamin-related proteins are closely linked to their ability to form nucleotide-dependent oligomers, a feature that also applies to hGBP-1 and hGBP-5. hGBPs are described as monomers, dimers, tetramers, and higher oligomeric species, the function of which is not clearly established. Therefore, this work focused on the oligomerization capability of hGBP-1 and hGBP-5, which are reported to assemble to homodimers and homotetramers. Employing independent methods such as size-exclusion chromatography, which relies on the hydrodynamic radius, and multiangle light scattering, which relies on the mass of the protein, revealed that previous interpretations regarding the size of the proteins and their complexes have to be revised. Additional studies using inter- and intramolecular Förster resonance energy transfer demonstrated that nucleotide-triggered intramolecular structural changes lead to a more extended shape of hGBP-1 being responsible for the appearance of larger oligomeric species. Thus, previously reported tetrameric and dimeric species of hGBP-1 and hGBP-5 were unmasked as dimers and monomers, respectively, with their shapes depending on both the bound nucleotide and the ionic strength of the solution.
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Affiliation(s)
- Semra Ince
- Physical Chemistry I, Ruhr-University Bochum, Germany
| | - Miriam Kutsch
- Physical Chemistry I, Ruhr-University Bochum, Germany
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310
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Lin MH, Liu YC, Liu SY, Chen FC, Yang PJ, Li GH, Liu PY, Yen CY. Clathrin-mediated endocytosis is required for ANE 30-100K-induced autophagy. J Oral Pathol Med 2017; 47:25-31. [PMID: 28520088 DOI: 10.1111/jop.12593] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/12/2017] [Indexed: 01/30/2023]
Abstract
BACKGROUND We identified an autophagy-inducing areca nut (AN) ingredient (AIAI) in the 30-100 kDa fraction of AN extract (ANE 30-100K). This study was to analyze the role of endocytosis in ANE 30-100K-induced autophagy. METHODS We used benzyl alcohol, dynasore, and shRNA of clathrin and dynamin to assess whether ANE 30-100K-induced cytotoxicity and accumulation of microtubule-associated protein 1 light chain 3 (LC3)-II were affected in oral (OECM-1) and esophageal (CE81T/VGH) carcinoma cells. RESULTS Both benzyl alcohol and dynasore effectively reduced ANE 30-100K-induced cytotoxicity and LC3-II accumulation in OECM-1 and CE81T/VGH cells. Downregulated protein expression of both clathrin and dynamin by their shRNA also significantly attenuated ANE 30-100K-induced elevation of LC3-II levels in CE81T/VGH cells. CONCLUSIONS These results indicate that AIAI may be engulfed by cells through clathrin-mediated endocytosis, which promotes the execution of the following autophagy program.
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Affiliation(s)
- Mei-Huei Lin
- Department of Biotechnology, Chia Nan University of Pharmacy, Tainan, Taiwan.,Department of Medical Research, Chi Mei Medical Center, Tainan, Taiwan
| | - Young-Chau Liu
- Department of Medical Research, Chi Mei Medical Center, Tainan, Taiwan.,Division of Natural Science, College of Liberal Education, Shu-Te University, Kaohsiung City, Taiwan
| | - Shyun-Yeu Liu
- Department of Dentistry, Taipei Medical University, Taipei, Taiwan.,Department of Dentistry, National Defense Medical Center, Taipei, Taiwan.,Oral and Maxillofacial Surgery Section, Chi Mei Medical Center, Tainan, Taiwan
| | - Fang-Chi Chen
- Department of Biotechnology, Chia Nan University of Pharmacy, Tainan, Taiwan
| | - Pei-Jung Yang
- Department of Biotechnology, Chia Nan University of Pharmacy, Tainan, Taiwan
| | - Guan-Hua Li
- Department of Biotechnology, Chia Nan University of Pharmacy, Tainan, Taiwan
| | - Pang-Yen Liu
- Department of Biotechnology, Chia Nan University of Pharmacy, Tainan, Taiwan
| | - Ching-Yu Yen
- Department of Dentistry, Taipei Medical University, Taipei, Taiwan.,Department of Dentistry, National Defense Medical Center, Taipei, Taiwan.,Oral and Maxillofacial Surgery Section, Chi Mei Medical Center, Tainan, Taiwan
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311
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Conformational dynamics of dynamin-like MxA revealed by single-molecule FRET. Nat Commun 2017; 8:15744. [PMID: 28548099 PMCID: PMC5458555 DOI: 10.1038/ncomms15744] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 04/25/2017] [Indexed: 12/14/2022] Open
Abstract
Human myxovirus resistance protein 1 (MxA) restricts a wide range of viruses and is closely related to the membrane-remodelling GTPase dynamin. The functions of MxA rely on domain rearrangements coupled with GTP hydrolysis cycles. To gain insight into this process, we studied real-time domain dynamics of MxA by single-molecule fluorescence resonance energy transfer. We find that the GTPase domain-bundle-signalling-element (BSE) region can adopt either an ‘open' or a ‘closed' conformation in all nucleotide-loading conditions. Whereas the open conformation is preferred in nucleotide-free, GDP·AlF4−-bound and GDP-bound forms, loading of GTP activates the relative movement between the two domains and alters the conformational preference to the ‘closed' state. Moreover, frequent relative movement was observed between BSE and stalk via hinge 1. On the basis of these results, we suggest how MxA molecules within a helical polymer collectively generate a stable torque through random GTP hydrolysis cycles. Our study provides mechanistic insights into fundamental cellular events such as viral resistance and endocytosis. MxA (myxovirus resistance protein A) is a viral restriction factor whose activity depends on self-assembly into polymeric rings and helical filaments. Here the authors reveal the conformational movements involved in generating torque within polymeric MxA molecules and the dynamic conformational changes that occur upon GTP loading and hydrolysis.
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312
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The Peroxisome-Mitochondria Connection: How and Why? Int J Mol Sci 2017; 18:ijms18061126. [PMID: 28538669 PMCID: PMC5485950 DOI: 10.3390/ijms18061126] [Citation(s) in RCA: 204] [Impact Index Per Article: 29.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Revised: 05/15/2017] [Accepted: 05/20/2017] [Indexed: 12/14/2022] Open
Abstract
Over the past decades, peroxisomes have emerged as key regulators in overall cellular lipid and reactive oxygen species metabolism. In mammals, these organelles have also been recognized as important hubs in redox-, lipid-, inflammatory-, and innate immune-signaling networks. To exert these activities, peroxisomes must interact both functionally and physically with other cell organelles. This review provides a comprehensive look of what is currently known about the interconnectivity between peroxisomes and mitochondria within mammalian cells. We first outline how peroxisomal and mitochondrial abundance are controlled by common sets of cis- and trans-acting factors. Next, we discuss how peroxisomes and mitochondria may communicate with each other at the molecular level. In addition, we reflect on how these organelles cooperate in various metabolic and signaling pathways. Finally, we address why peroxisomes and mitochondria have to maintain a healthy relationship and why defects in one organelle may cause dysfunction in the other. Gaining a better insight into these issues is pivotal to understanding how these organelles function in their environment, both in health and disease.
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313
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Abstract
Exocytosis is an important cellular process controlled by metabolic signaling. It involves vesicle fusion to the plasma membrane, followed by the opening of a fusion pore, and the subsequent release of the vesicular lumen content into the extracellular space. While most modeling efforts focus on the events leading to membrane fusion, how the vesicular membrane remodels after fusing to plasma membrane remains unclear. This latter event dictates the nature and the efficiency of exocytotic vesicular secretions, and is thus critical for exocytotic function. We provide a generic membrane mechanical model to systematically study the fate of post-fusion vesicles. We show that while membrane stiffness favors full-collapse vesicle fusion into the plasma membrane, the intravesicular pressure swells the vesicle and causes the fusion pore to shrink. Dimensions of the vesicle and its associated fusion pore further modulate this mechanical antagonism. We systematically define the mechanical conditions that account for the full spectrum of the observed vesicular secretion modes. Our model therefore can serve as a unified theoretical framework that sheds light on the elaborate control mechanism of exocytosis.
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Affiliation(s)
- Thomas Stephens
- Biochemistry and Biophysics Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, United States of America. Equal contribution
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314
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Gormal R, Valmas N, Fath T, Meunier F. A role for tropomyosins in activity-dependent bulk endocytosis? Mol Cell Neurosci 2017; 84:112-118. [PMID: 28545680 DOI: 10.1016/j.mcn.2017.04.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 04/06/2017] [Accepted: 04/11/2017] [Indexed: 02/06/2023] Open
Abstract
Bulk endocytosis allows stimulated neurons to take up a large portion of the presynaptic plasma membrane in order to regenerate synaptic vesicle pools. Actin, one of the most abundant proteins in eukaryotic cells, plays an important role in this process, but a detailed mechanistic understanding of the involvement of the cortical actin network is still lacking, in part due to the relatively small size of nerve terminals and the limitation of optical microscopy. We recently discovered that neurosecretory cells display a similar, albeit much larger, form of bulk endocytosis in response to secretagogue stimulation. This allowed us to identify a novel highly dynamic role for the acto-myosin II cortex in generating constricting rings that precede the fission of nascent bulk endosomes. In this review we focus on the mechanism underpinning this dramatic switch in the organization and function of the cortical actin network. We provide additional experimental data that suggest a role of tropomyosin Tpm3.1 and Tpm4.2 in this process, together with an emerging model of how actin controls bulk endocytosis.
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Affiliation(s)
- Rachel Gormal
- The University of Queensland, Queensland Brain Institute, Clem Jones Centre for Ageing Dementia Research, Brisbane, Queensland 4072, Australia
| | - Nicholas Valmas
- The University of Queensland, Queensland Brain Institute, Brisbane, Queensland 4072, Australia
| | - Thomas Fath
- School of Medical Sciences, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Frederic Meunier
- The University of Queensland, Queensland Brain Institute, Clem Jones Centre for Ageing Dementia Research, Brisbane, Queensland 4072, Australia.
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315
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Zala D, Schlattner U, Desvignes T, Bobe J, Roux A, Chavrier P, Boissan M. The advantage of channeling nucleotides for very processive functions. F1000Res 2017; 6:724. [PMID: 28663786 PMCID: PMC5473427 DOI: 10.12688/f1000research.11561.2] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/17/2017] [Indexed: 12/26/2022] Open
Abstract
Nucleoside triphosphate (NTP)s, like ATP (adenosine 5'-triphosphate) and GTP (guanosine 5'-triphosphate), have long been considered sufficiently concentrated and diffusible to fuel all cellular ATPases (adenosine triphosphatases) and GTPases (guanosine triphosphatases) in an energetically healthy cell without becoming limiting for function. However, increasing evidence for the importance of local ATP and GTP pools, synthesised in close proximity to ATP- or GTP-consuming reactions, has fundamentally challenged our view of energy metabolism. It has become evident that cellular energy metabolism occurs in many specialised 'microcompartments', where energy in the form of NTPs is transferred preferentially from NTP-generating modules directly to NTP-consuming modules. Such energy channeling occurs when diffusion through the cytosol is limited, where these modules are physically close and, in particular, if the NTP-consuming reaction has a very high turnover, i.e. is very processive. Here, we summarise the evidence for these conclusions and describe new insights into the physiological importance and molecular mechanisms of energy channeling gained from recent studies. In particular, we describe the role of glycolytic enzymes for axonal vesicle transport and nucleoside diphosphate kinases for the functions of dynamins and dynamin-related GTPases.
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Affiliation(s)
- Diana Zala
- ESPCI - Paris, PSL Research University, Paris, F-75005, France.,CNRS, UMR8249, Paris, F-75005, France
| | - Uwe Schlattner
- Laboratory of Fundamental and Applied Bioenergetics (LBFA), and SFR Environmental and Systems Biology (BEeSy), U1055, University Grenoble Alpes, Grenoble, 38058, France.,Inserm-U1055, Grenoble, F-38058, France
| | - Thomas Desvignes
- Institute of Neuroscience, University of Oregon, Eugene, OR, 97401, USA
| | - Julien Bobe
- INRA, UR1037 LPGP, Campus de Beaulieu, Rennes, F-35000, France
| | - Aurélien Roux
- Department of Biochemistry, University of Geneva, Geneva, CH-1211, Switzerland.,Swiss National Centre for Competence in Research Programme Chemical Biology, Geneva, CH-1211, Switzerland
| | - Philippe Chavrier
- Institut Curie, Paris, F-75248, France.,PSL Research University, Paris, F-75005, France.,CNRS, UMR144, Paris, F-75248, France
| | - Mathieu Boissan
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, UMRS938, Saint-Antoine Research Center, Paris, F-75012, France.,AP-HP, Hospital Tenon, Service de Biochimie et Hormonologie, Paris, F-75020, France
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316
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Zala D, Schlattner U, Desvignes T, Bobe J, Roux A, Chavrier P, Boissan M. The advantage of channeling nucleotides for very processive functions. F1000Res 2017; 6:724. [PMID: 28663786 DOI: 10.12688/f1000research.11561.1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/15/2017] [Indexed: 01/01/2023] Open
Abstract
Nucleoside triphosphate (NTP)s, like ATP (adenosine 5'-triphosphate) and GTP (guanosine 5'-triphosphate), have long been considered sufficiently concentrated and diffusible to fuel all cellular ATPases (adenosine triphosphatases) and GTPases (guanosine triphosphatases) in an energetically healthy cell without becoming limiting for function. However, increasing evidence for the importance of local ATP and GTP pools, synthesised in close proximity to ATP- or GTP-consuming reactions, has fundamentally challenged our view of energy metabolism. It has become evident that cellular energy metabolism occurs in many specialised 'microcompartments', where energy in the form of NTPs is transferred preferentially from NTP-generating modules directly to NTP-consuming modules. Such energy channeling occurs when diffusion through the cytosol is limited, where these modules are physically close and, in particular, if the NTP-consuming reaction has a very high turnover, i.e. is very processive. Here, we summarise the evidence for these conclusions and describe new insights into the physiological importance and molecular mechanisms of energy channeling gained from recent studies. In particular, we describe the role of glycolytic enzymes for axonal vesicle transport and nucleoside diphosphate kinases for the functions of dynamins and dynamin-related GTPases.
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Affiliation(s)
- Diana Zala
- ESPCI - Paris, PSL Research University, Paris, F-75005, France.,CNRS, UMR8249, Paris, F-75005, France
| | - Uwe Schlattner
- Laboratory of Fundamental and Applied Bioenergetics (LBFA), and SFR Environmental and Systems Biology (BEeSy), U1055, University Grenoble Alpes, Grenoble, 38058, France.,Inserm-U1055, Grenoble, F-38058, France
| | - Thomas Desvignes
- Institute of Neuroscience, University of Oregon, Eugene, OR, 97401, USA
| | - Julien Bobe
- INRA, UR1037 LPGP, Campus de Beaulieu, Rennes, F-35000, France
| | - Aurélien Roux
- Department of Biochemistry, University of Geneva, Geneva, CH-1211, Switzerland.,Swiss National Centre for Competence in Research Programme Chemical Biology, Geneva, CH-1211, Switzerland
| | - Philippe Chavrier
- Institut Curie, Paris, F-75248, France.,PSL Research University, Paris, F-75005, France.,CNRS, UMR144, Paris, F-75248, France
| | - Mathieu Boissan
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, UMRS938, Saint-Antoine Research Center, Paris, F-75012, France.,AP-HP, Hospital Tenon, Service de Biochimie et Hormonologie, Paris, F-75020, France
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317
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Dynamic remodeling of the dynamin helix during membrane constriction. Proc Natl Acad Sci U S A 2017; 114:5449-5454. [PMID: 28484031 DOI: 10.1073/pnas.1619578114] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Dynamin is a dimeric GTPase that assembles into a helix around the neck of endocytic buds. Upon GTP hydrolysis, dynamin breaks these necks, a reaction called membrane fission. Fission requires dynamin to first constrict the membrane. It is unclear, however, how dynamin helix constriction works. Here we undertake a direct high-speed atomic force microscopy imaging analysis to visualize the constriction of single dynamin-coated membrane tubules. We show GTP-induced dynamic rearrangements of the dynamin helix turns: the average distances between turns reduce with GTP hydrolysis. These distances vary, however, over time because helical turns were observed to transiently pair and dissociate. At fission sites, these cycles of association and dissociation were correlated with relative lateral displacement of the turns and constriction. Our findings show relative longitudinal and lateral displacements of helical turns related to constriction. Our work highlights the potential of high-speed atomic force microscopy for the observation of mechanochemical proteins onto membranes during action at almost molecular resolution.
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318
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Bordi M, Nazio F, Campello S. The Close Interconnection between Mitochondrial Dynamics and Mitophagy in Cancer. Front Oncol 2017; 7:81. [PMID: 28512624 PMCID: PMC5411450 DOI: 10.3389/fonc.2017.00081] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 04/11/2017] [Indexed: 01/11/2023] Open
Abstract
Recent decades have revealed the shape changes of mitochondria and their regulators to be main players in a plethora of physiological cell processes. Mitochondria are extremely dynamic organelles whose highly controlled morphological changes respond to specific and diverse pathophysiological needs. Thus, their qualitative control is crucial for the determination of cell function and fate. Moreover, ever-new metabolic changes, mainly attributable to mitochondrial (dys)functions, are strongly connected to cancer and its microenvironment. For this reason, the aspects controlling mitochondria activity and status are in the oncological spotlight. In this review, we elucidate the most intriguing discoveries related to two apparently independent but strictly interconnected processes crucial for the organelle functionality and fate, mitochondrial dynamics, and mitophagy. We will mostly focus on their metabolic interconnections and regulations that can causally foster a tumoral context.
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Affiliation(s)
- Matteo Bordi
- Department of Biology, University of Rome Tor Vergata, Rome, Italy
| | - Francesca Nazio
- Department of Pediatric Hematology and Oncology, IRCCS Bambino Gesù Children's Hospital, Rome, Italy
| | - Silvia Campello
- Department of Biology, University of Rome Tor Vergata, Rome, Italy.,IRCCS, Fondazione Santa Lucia, Rome, Italy
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319
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Abstract
Membrane fission, which facilitates compartmentalization of biological processes into discrete, membrane-bound volumes, is essential for cellular life. Proteins with specific structural features including constricting rings, helical scaffolds, and hydrophobic membrane insertions are thought to be the primary drivers of fission. In contrast, here we report a mechanism of fission that is independent of protein structure-steric pressure among membrane-bound proteins. In particular, random collisions among crowded proteins generate substantial pressure, which if unbalanced on the opposite membrane surface can dramatically increase membrane curvature, leading to fission. Using the endocytic protein epsin1 N-terminal homology domain (ENTH), previously thought to drive fission by hydrophobic insertion, our results show that membrane coverage correlates equally with fission regardless of the hydrophobicity of insertions. Specifically, combining FRET-based measurements of membrane coverage with multiple, independent measurements of membrane vesiculation revealed that fission became spontaneous as steric pressure increased. Further, fission efficiency remained equally potent when helices were replaced by synthetic membrane-binding motifs. These data challenge the view that hydrophobic insertions drive membrane fission, suggesting instead that the role of insertions is to anchor proteins strongly to membrane surfaces, amplifying steric pressure. In line with these conclusions, even green fluorescent protein (GFP) was able to drive fission efficiently when bound to the membrane at high coverage. Our conclusions are further strengthened by the finding that intrinsically disordered proteins, which have large hydrodynamic radii yet lack a defined structure, drove fission with substantially greater potency than smaller, structured proteins.
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320
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Stephan M, Edelmann B, Winoto-Morbach S, Janssen O, Bertsch U, Perrotta C, Schütze S, Fritsch J. Role of caspases in CD95-induced biphasic activation of acid sphingomyelinase. Oncotarget 2017; 8:20067-20085. [PMID: 28223543 PMCID: PMC5386744 DOI: 10.18632/oncotarget.15379] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Accepted: 01/24/2017] [Indexed: 12/04/2022] Open
Abstract
Acid sphingomyelinase (A-SMase) plays an important role in the initiation of CD95 signaling by forming ceramide-enriched membrane domains that enable clustering and activation of the death receptors. In TNF-R1 and TRAIL-R1/R2 signaling, A-SMase also contributes to the lysosomal apoptosis pathway triggered by receptor internalization. Here, we investigated the molecular mechanism of CD95-mediated A-SMase activation, demonstrating that A-SMase is located in internalized CD95-receptosomes and is activated by the CD95/CD95L complex in a biphasic manner.Since several caspases have been described to be involved in the activation of A-SMase, we evaluated expression levels of caspase-8, caspase-7 and caspase-3 in CD95-receptosomes. The occurrence of cleaved caspase-8 correlated with the first peak of A-SMase activity and translocation of the A-SMase to the cell surface which could be blocked by the caspase-8 inhibitor IETD.Inhibition of CD95-internalization selectively reduced the second phase of A-SMase activity, suggesting a fusion between internalized CD95-receptosomes and an intracellular vesicular pool of A-SMase. Further analysis demonstrated that caspase-7 activity correlates with the second phase of the A-SMase activity, whereas active caspase-3 is present at early and late internalization time points. Blocking caspases-7/ -3 by DEVD reduced the second phase of A-SMase activation in CD95-receptosomes suggesting the potential role of caspase-7 or -3 for late A-SMase activation.In summary, we describe a biphasic A-SMase activation in CD95-receptosomes indicating (I.) a caspase-8 dependent translocation of A-SMase to plasma membrane and (II.) a caspase-7 and/or -3 dependent fusion of internalized CD95-receptosomes with intracellular A-SMase-containing vesicles.
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Affiliation(s)
- Mario Stephan
- Institute of Immunology, Christian-Albrechts-University of Kiel, Kiel, Germany
| | - Bärbel Edelmann
- Department of Hematology and Oncology, University Hospital Magdeburg, Magdeburg, Germany
| | | | - Ottmar Janssen
- Institute of Immunology, Christian-Albrechts-University of Kiel, Kiel, Germany
| | - Uwe Bertsch
- Institute of Immunology, Christian-Albrechts-University of Kiel, Kiel, Germany
| | - Cristiana Perrotta
- Department of Biomedical and Clinical Sciences “Luigi Sacco” (DIBIC), Università degli Studi di Milano, Milano, Italy
| | - Stefan Schütze
- Institute of Immunology, Christian-Albrechts-University of Kiel, Kiel, Germany
| | - Jürgen Fritsch
- Institute of Immunology, Christian-Albrechts-University of Kiel, Kiel, Germany
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321
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Kweon DH, Kong B, Shin YK. Hemifusion in Synaptic Vesicle Cycle. Front Mol Neurosci 2017; 10:65. [PMID: 28360835 PMCID: PMC5352705 DOI: 10.3389/fnmol.2017.00065] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Accepted: 02/27/2017] [Indexed: 01/04/2023] Open
Abstract
In the neuron, early neurotransmitters are released through the fusion pore prior to the complete vesicle fusion. It has been thought that the fusion pore is a gap junction-like structure made of transmembrane domains (TMDs) of soluble N-ethylmaleimide-sensitive-factor attachment protein receptor (SNARE) proteins. However, evidence has accumulated that lipid mixing occurs prior to the neurotransmitter release through the fusion pore lined predominantly with lipids. To explain these observations, the hemifusion, a membrane structure in which two bilayers are partially merged, has emerged as a key step preceding the formation of the fusion pore. Furthermore, the hemifusion appears to be the bona fide intermediate step not only for the synaptic vesicle cycle, but for a wide range of membrane remodeling processes, such as viral membrane fusion and endocytotic membrane fission.
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Affiliation(s)
- Dae-Hyuk Kweon
- Department of Genetic Engineering, College of Biotechnology and Bioengineering, Sungkyunkwan University Suwon, South Korea
| | - Byoungjae Kong
- Department of Genetic Engineering, College of Biotechnology and Bioengineering, Sungkyunkwan University Suwon, South Korea
| | - Yeon-Kyun Shin
- Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University Ames, IA, USA
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322
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Curchoe CL, Manor U. Actin Cytoskeleton-Mediated Constriction of Membrane Organelles via Endoplasmic Reticulum Scaffolding. ACS Biomater Sci Eng 2017; 3:2727-2732. [PMID: 29250592 DOI: 10.1021/acsbiomaterials.6b00802] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Intracellular organelles constantly undergo fission to facilitate turnover, transport, and functional changes. The cytoskeleton has long been understood to play a role in these events, and recent work strongly suggests that several conserved molecular players cooperate with the cytoskeleton to mediate the fission process. Membrane curvature-inducing, membrane scission proteins, and force-inducing cytoskeletal proteins all cooperate to drive the fission process. Recent work suggests that the endoplasmic reticulum serves as the linchpin that orchestrates and spatially organizes fission via these curvature-inducing, scission, and force-producing molecules. This all leads us to postulate a "universal theory" of organelle fission with distinct biophysical and biochemical features mediated by a finite number of physical and molecular constraints. This new physical paradigm deserves special attention from those who wish to model these processes, since previous theoretical and experimental attempts to elucidate these fission mechanisms have not included the organizing factor of the endoplasmic reticulum. Here we review the basic concepts of this new model for organelle fission, and explore the implications thereof. Previous studies that didn't include this component can now be interpreted in light of these new data and serve as a useful guide for understanding how this process happens in vivo. Thus, this review provides direction for future modeling and experimental efforts to better understand how these complex systems and processes are regulated in both healthy and diseased biological systems.
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Affiliation(s)
- Carol Lynn Curchoe
- Waitt Advanced Biophotonics Center, The Salk Institute for Biological Studies, 10010 N Torrey Pines Rd., La Jolla, CA 92037
| | - Uri Manor
- Waitt Advanced Biophotonics Center, The Salk Institute for Biological Studies, 10010 N Torrey Pines Rd., La Jolla, CA 92037
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323
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Recursive Alterations of the Relationship between Simple Membrane Geometry and Insertion of Amphiphilic Motifs. MEMBRANES 2017; 7:membranes7010006. [PMID: 28208740 PMCID: PMC5371967 DOI: 10.3390/membranes7010006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 12/23/2016] [Accepted: 01/05/2017] [Indexed: 11/30/2022]
Abstract
The shape and composition of a membrane directly regulate the localization, activity, and signaling properties of membrane associated proteins. Proteins that both sense and generate membrane curvature, e.g., through amphiphilic insertion motifs, potentially engage in recursive binding dynamics, where the recruitment of the protein itself changes the properties of the membrane substrate. Simple geometric models of membrane curvature interactions already provide prediction tools for experimental observations, however these models are treating curvature sensing and generation as separated phenomena. Here, we outline a model that applies both geometric and basic thermodynamic considerations. This model allows us to predict the consequences of recursive properties in such interaction schemes and thereby integrate the membrane as a dynamic substrate. We use this combined model to hypothesize the origin and properties of tubular carrier systems observed in cells. Furthermore, we pinpoint the coupling to a membrane reservoir as a factor that influences the membrane curvature sensing and generation properties of local curvatures in the cell in line with classic determinants such as lipid composition and membrane geometry.
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324
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Updegrove TB, Ramamurthi KS. Geometric protein localization cues in bacterial cells. Curr Opin Microbiol 2017; 36:7-13. [PMID: 28110195 DOI: 10.1016/j.mib.2016.12.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 12/15/2016] [Accepted: 12/17/2016] [Indexed: 10/20/2022]
Abstract
Bacterial cells are highly organized at a molecular level. Understanding how specific proteins localize to their proper subcellular address has been a major challenge in bacterial cell biology. One mechanism, which appears to be increasingly more common, is the use of 'geometric cues' for protein localization. In this model, certain shape-sensing proteins recognize, and preferentially embed into, either negatively or positively curved (concave or convex, respectively) membranes. Here, we review examples of bacterial proteins that reportedly localize by sensing geometric cues and highlight emerging mechanistic understandings of how proteins may recognize subtle differences in membrane curvature.
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Affiliation(s)
- Taylor B Updegrove
- Laboratory of Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, United States
| | - Kumaran S Ramamurthi
- Laboratory of Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, United States.
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325
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Hughes L, Borrett S, Towers K, Starborg T, Vaughan S. Patterns of organelle ontogeny through a cell cycle revealed by whole-cell reconstructions using 3D electron microscopy. J Cell Sci 2017; 130:637-647. [PMID: 28049718 DOI: 10.1242/jcs.198887] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Accepted: 12/01/2016] [Indexed: 12/29/2022] Open
Abstract
The major mammalian bloodstream form of the African sleeping sickness parasite Trypanosoma brucei multiplies rapidly, and it is important to understand how these cells divide. Organelle inheritance involves complex spatiotemporal re-arrangements to ensure correct distribution to daughter cells. Here, serial block face scanning electron microscopy (SBF-SEM) was used to reconstruct whole individual cells at different stages of the cell cycle to give an unprecedented temporal, spatial and quantitative view of organelle division, inheritance and abscission in a eukaryotic cell. Extensive mitochondrial branching occurred only along the ventral surface of the parasite, but the mitochondria returned to a tubular form during cytokinesis. Fission of the mitochondrion occurred within the cytoplasmic bridge during the final stage of cell division, correlating with cell abscission. The nuclei were located underneath each flagellum at mitosis and the mitotic spindle was located along the ventral surface, further demonstrating the asymmetric arrangement of cell cleavage in trypanosomes. Finally, measurements demonstrated that multiple Golgi bodies were accurately positioned along the flagellum attachment zone, suggesting a mechanism for determining the location of Golgi bodies along each flagellum during the cell cycle.
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Affiliation(s)
- Louise Hughes
- Department of Biological and Medical Sciences, Faculty of Health and Life Science, Oxford Brookes University, Oxford OX3 0BP, UK
| | - Samantha Borrett
- Department of Biological and Medical Sciences, Faculty of Health and Life Science, Oxford Brookes University, Oxford OX3 0BP, UK
| | - Katie Towers
- Department of Biological and Medical Sciences, Faculty of Health and Life Science, Oxford Brookes University, Oxford OX3 0BP, UK
| | - Tobias Starborg
- Wellcome Centre for Cell Matrix Research, University of Manchester, Michael Smith Building, Manchester M13 9PT, UK
| | - Sue Vaughan
- Department of Biological and Medical Sciences, Faculty of Health and Life Science, Oxford Brookes University, Oxford OX3 0BP, UK
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326
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Affiliation(s)
- Heidi M McBride
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Adam Frost
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, California 94143, USA
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327
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Antonny B, Burd C, De Camilli P, Chen E, Daumke O, Faelber K, Ford M, Frolov VA, Frost A, Hinshaw JE, Kirchhausen T, Kozlov MM, Lenz M, Low HH, McMahon H, Merrifield C, Pollard TD, Robinson PJ, Roux A, Schmid S. Membrane fission by dynamin: what we know and what we need to know. EMBO J 2016; 35:2270-2284. [PMID: 27670760 PMCID: PMC5090216 DOI: 10.15252/embj.201694613] [Citation(s) in RCA: 327] [Impact Index Per Article: 40.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Accepted: 07/25/2016] [Indexed: 12/04/2022] Open
Abstract
The large GTPase dynamin is the first protein shown to catalyze membrane fission. Dynamin and its related proteins are essential to many cell functions, from endocytosis to organelle division and fusion, and it plays a critical role in many physiological functions such as synaptic transmission and muscle contraction. Research of the past three decades has focused on understanding how dynamin works. In this review, we present the basis for an emerging consensus on how dynamin functions. Three properties of dynamin are strongly supported by experimental data: first, dynamin oligomerizes into a helical polymer; second, dynamin oligomer constricts in the presence of GTP; and third, dynamin catalyzes membrane fission upon GTP hydrolysis. We present the two current models for fission, essentially diverging in how GTP energy is spent. We further discuss how future research might solve the remaining open questions presently under discussion.
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Affiliation(s)
- Bruno Antonny
- CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, Université de Nice Sophia-Antipolis, Valbonne, France
| | - Christopher Burd
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
| | - Pietro De Camilli
- Departments of Neuroscience and Cell Biology, Howard Hughes Medical Institute and Kavli Institute for Neuroscience, Yale University School of Medicine, New Haven, CT, USA
| | - Elizabeth Chen
- Department of Molecular Biology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Oliver Daumke
- Department of Crystallography, Max-Delbrück Centrum für Molekulare Medizin, Berlin, Germany
| | - Katja Faelber
- Department of Crystallography, Max-Delbrück Centrum für Molekulare Medizin, Berlin, Germany
| | - Marijn Ford
- Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Vadim A Frolov
- Biofisika Institute (CSIC, UPV/EHU) and Department of Biochemistry and Molecular Biology, University of the Basque Country, Leioa, Spain.,IKERBASQUE, Basque Foundation for Science, Bilbao, Spain
| | - Adam Frost
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA, USA
| | - Jenny E Hinshaw
- Laboratory of Cell and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, MD, USA
| | - Tom Kirchhausen
- Departments of Cell Biology and Pediatrics, Harvard Medical School, Boston, MA, USA.,Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA, USA
| | - Michael M Kozlov
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Martin Lenz
- LPTMS, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Orsay, France
| | - Harry H Low
- Department of Life Sciences, Imperial College, London, UK
| | | | | | - Thomas D Pollard
- Department of Molecular Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - Phillip J Robinson
- Cell Signalling Unit, Children's Medical Research Institute, The University of Sydney, Westmead, NSW, Australia
| | - Aurélien Roux
- Department of Biochemistry and Swiss NCCR Chemical Biology, University of Geneva, Geneva 4, Switzerland
| | - Sandra Schmid
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX, USA
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