1
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Picas L, André-Arpin C, Comunale F, Bousquet H, Tsai FC, Rico F, Maiuri P, Pernier J, Bodin S, Nicot AS, Laporte J, Bassereau P, Goud B, Gauthier-Rouvière C, Miserey S. BIN1 regulates actin-membrane interactions during IRSp53-dependent filopodia formation. Commun Biol 2024; 7:549. [PMID: 38724689 PMCID: PMC11082164 DOI: 10.1038/s42003-024-06168-8] [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: 05/02/2023] [Accepted: 04/09/2024] [Indexed: 05/12/2024] Open
Abstract
Amphiphysin 2 (BIN1) is a membrane and actin remodeling protein mutated in congenital and adult centronuclear myopathies. Here, we report an unexpected function of this N-BAR domain protein BIN1 in filopodia formation. We demonstrated that BIN1 expression is necessary and sufficient to induce filopodia formation. BIN1 is present at the base of forming filopodia and all along filopodia, where it colocalizes with F-actin. We identify that BIN1-mediated filopodia formation requires IRSp53, which allows its localization at negatively-curved membrane topologies. Our results show that BIN1 bundles actin in vitro. Finally, we identify that BIN1 regulates the membrane-to-cortex architecture and functions as a molecular platform to recruit actin-binding proteins, dynamin and ezrin, to promote filopodia formation.
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Affiliation(s)
- Laura Picas
- Institut de Recherche en Infectiologie de Montpellier (IRIM), University of Montpellier, CNRS UMR 9004, Montpellier, France.
| | - Charlotte André-Arpin
- Institut de Recherche en Infectiologie de Montpellier (IRIM), University of Montpellier, CNRS UMR 9004, Montpellier, France
| | - Franck Comunale
- CRBM, University of Montpellier, CNRS UMR 5237, Montpellier, France
| | - Hugo Bousquet
- Institut Curie, CNRS UMR 144, PSL Research University, Paris, France
| | - Feng-Ching Tsai
- Institut Curie, CNRS UMR 168, PSL Research University, Paris, France
| | - Félix Rico
- Aix-Marseille Université, U1325 INSERM, DyNaMo, Turing center for living systems, Marseille, France
| | - Paolo Maiuri
- Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Università degli Studi di Napoli Federico II, Naples, Italy
| | - Julien Pernier
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Stéphane Bodin
- CRBM, University of Montpellier, CNRS UMR 5237, Montpellier, France
| | - Anne-Sophie Nicot
- Grenoble Alpes University, INSERM U1216, Grenoble Institut Neurosciences, Grenoble, France
| | - Jocelyn Laporte
- Department of Translational Medicine, IGBMC, U1258, UMR7104 Strasbourg University, Collège de France, Illkirch, France
| | | | - Bruno Goud
- Institut Curie, CNRS UMR 144, PSL Research University, Paris, France
| | | | - Stéphanie Miserey
- Institut Curie, CNRS UMR 144, PSL Research University, Paris, France.
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2
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Zhu K, Guo X, Chandrasekaran A, Miao X, Rangamani P, Zhao W, Miao Y. Membrane curvature catalyzes actin nucleation through nano-scale condensation of N-WASP-FBP17. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.25.591054. [PMID: 38712166 PMCID: PMC11071460 DOI: 10.1101/2024.04.25.591054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Actin remodeling is spatiotemporally regulated by surface topographical cues on the membrane for signaling across diverse biological processes. Yet, the mechanism dynamic membrane curvature prompts quick actin cytoskeletal changes in signaling remain elusive. Leveraging the precision of nanolithography to control membrane curvature, we reconstructed catalytic reactions from the detection of nano-scale curvature by sensing molecules to the initiation of actin polymerization, which is challenging to study quantitatively in living cells. We show that this process occurs via topographical signal-triggered condensation and activation of the actin nucleation-promoting factor (NPF), Neuronal Wiskott-Aldrich Syndrome protein (N-WASP), which is orchestrated by curvature-sensing BAR-domain protein FBP17. Such N-WASP activation is fine-tuned by optimizing FBP17 to N-WASP stoichiometry over different curvature radii, allowing a curvature-guided macromolecular assembly pattern for polymerizing actin network locally. Our findings shed light on the intricate relationship between changes in curvature and actin remodeling via spatiotemporal regulation of NPF/BAR complex condensation.
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3
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Ledoux B, Zanin N, Yang J, Mercier V, Coster C, Dupont-Gillain C, Alsteens D, Morsomme P, Renard HF. Plasma membrane nanodeformations promote actin polymerization through CIP4/CDC42 recruitment and regulate type II IFN signaling. SCIENCE ADVANCES 2023; 9:eade1660. [PMID: 38091386 PMCID: PMC10848735 DOI: 10.1126/sciadv.ade1660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 11/10/2023] [Indexed: 12/18/2023]
Abstract
In their environment, cells must cope with mechanical stresses constantly. Among these, nanoscale deformations of plasma membrane induced by substrate nanotopography are now largely accepted as a biophysical stimulus influencing cell behavior and function. However, the mechanotransduction cascades involved and their precise molecular effects on cellular physiology are still poorly understood. Here, using homemade fluorescent nanostructured cell culture surfaces, we explored the role of Bin/Amphiphysin/Rvs (BAR) domain proteins as mechanosensors of plasma membrane geometry. Our data reveal that distinct subsets of BAR proteins bind to plasma membrane deformations in a membrane curvature radius-dependent manner. Furthermore, we show that membrane curvature promotes the formation of dynamic actin structures mediated by the Rho GTPase CDC42, the F-BAR protein CIP4, and the presence of PI(4,5)P2. In addition, these actin-enriched nanodomains can serve as platforms to regulate receptor signaling as they appear to contain interferon-γ receptor (IFNγ-R) and to lead to the partial inhibition of IFNγ-induced JAK/STAT signaling.
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Affiliation(s)
- Benjamin Ledoux
- UCLouvain, Louvain Institute of Biomolecular Science and Technology, Group of Molecular Physiology, Croix du Sud 4-5 bte L7.07.14, Louvain-la-Neuve 1348, Belgium
- UCLouvain, Louvain Institute of Biomolecular Science and Technology, NanoBiophysics lab, Croix du Sud 4-5 bte L7.07.07, Louvain-la-Neuve 1348, Belgium
- UNamur, Morph-Im platform, Rue de Bruxelles 61, Namur 5000, Belgium
| | - Natacha Zanin
- UNamur, NAmur Research Institute for LIfe Sciences, Unité de Recherche en Biologie Cellulaire animale, Rue de Bruxelles 61, Namur 5000, Belgium
| | - Jinsung Yang
- Gyeongsang National University, Department of Biochemistry, College of Medicine, Department of Convergence Medical Sciences, Institute of Medical Science, Jinju 52727, South Korea
| | - Vincent Mercier
- Department of Biochemistry, University of Geneva, Geneva, Switzerland
| | - Charlotte Coster
- UCLouvain, Louvain Institute of Biomolecular Science and Technology, Group of Molecular Physiology, Croix du Sud 4-5 bte L7.07.14, Louvain-la-Neuve 1348, Belgium
| | - Christine Dupont-Gillain
- UCLouvain, Institute of Condensed Matter and Nanosciences, Bio- and Soft Matter, Place Louis Pasteur 1 bte L4.01.10, Louvain-la-Neuve 1348, Belgium
| | - David Alsteens
- UCLouvain, Louvain Institute of Biomolecular Science and Technology, NanoBiophysics lab, Croix du Sud 4-5 bte L7.07.07, Louvain-la-Neuve 1348, Belgium
| | - Pierre Morsomme
- UCLouvain, Louvain Institute of Biomolecular Science and Technology, Group of Molecular Physiology, Croix du Sud 4-5 bte L7.07.14, Louvain-la-Neuve 1348, Belgium
| | - Henri-François Renard
- UNamur, Morph-Im platform, Rue de Bruxelles 61, Namur 5000, Belgium
- UNamur, NAmur Research Institute for LIfe Sciences, Unité de Recherche en Biologie Cellulaire animale, Rue de Bruxelles 61, Namur 5000, Belgium
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4
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Has C, Das SL. The Functionality of Membrane-Inserting Proteins and Peptides: Curvature Sensing, Generation, and Pore Formation. J Membr Biol 2023; 256:343-372. [PMID: 37650909 DOI: 10.1007/s00232-023-00289-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 08/04/2023] [Indexed: 09/01/2023]
Abstract
Proteins and peptides with hydrophobic and amphiphilic segments are responsible for many biological functions. The sensing and generation of membrane curvature are the functions of several protein domains or motifs. While some specific membrane proteins play an essential role in controlling the curvature of distinct intracellular membranes, others participate in various cellular processes such as clathrin-mediated endocytosis, where several proteins sort themselves at the neck of the membrane bud. A few membrane-inserting proteins form nanopores that permeate selective ions and water to cross the membrane. In addition, many natural and synthetic small peptides and protein toxins disrupt the membrane by inducing nonspecific pores in the membrane. The pore formation causes cell death through the uncontrolled exchange between interior and exterior cellular contents. In this article, we discuss the insertion depth and orientation of protein/peptide helices, and their role as a sensor and inducer of membrane curvature as well as a pore former in the membrane. We anticipate that this extensive review will assist biophysicists to gain insight into curvature sensing, generation, and pore formation by membrane insertion.
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Affiliation(s)
- Chandra Has
- Department of Chemical Engineering, GSFC University, Vadodara, 391750, Gujarat, India.
| | - Sovan Lal Das
- Physical and Chemical Biology Laboratory and Department of Mechanical Engineering, Indian Institute of Technology, Palakkad, 678623, Kerala, India
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5
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Valenzuela-Valderas KN, Farrashzadeh E, Chang YY, Shi Y, Raudonis R, Leung BM, Rohde JR, Enninga J, Cheng Z. RACK1 promotes Shigella flexneri actin-mediated invasion, motility, and cell-to-cell spreading. iScience 2023; 26:108216. [PMID: 37953961 PMCID: PMC10637933 DOI: 10.1016/j.isci.2023.108216] [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: 04/28/2023] [Revised: 08/19/2023] [Accepted: 10/11/2023] [Indexed: 11/14/2023] Open
Abstract
Shigella flexneri is an intracellular bacterium that hijacks the host actin cytoskeleton to invade and disseminate within the colonic epithelium. Shigella's virulence factors induce actin polymerization, leading to bacterial uptake, actin tail formation, actin-mediated motility, and cell-to-cell spreading. Many host factors involved in the Shigella-prompted actin rearrangements remain elusive. Here, we studied the role of a host protein receptor for activated C kinase 1 (RACK1) in actin cytoskeleton dynamics and Shigella infection. We used time-lapse imaging to demonstrate that RACK1 facilitates Shigella-induced actin cytoskeleton remodeling at multiple levels during infection of epithelial cells. Silencing RACK1 expression impaired Shigella-induced rapid polymerizing structures, reducing host cell invasion, bacterial motility, and cell-to-cell spreading. In uninfected cells, RACK1 silencing reduced jasplakinolide-mediated filamentous actin aggregate formation and negatively affected actin turnover in fast polymerizing structures, such as membrane ruffles. Our findings provide a role of RACK1 in actin cytoskeleton dynamics and Shigella infection.
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Affiliation(s)
| | - Elmira Farrashzadeh
- Department of Microbiology and Immunology, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | - Yuen-Yan Chang
- Unité Dynamique des interactions hôtes-pathogènes, Institut Pasteur and CNRS UMR3691, Université de Paris-Cité, 75724 Paris, France
| | - Yunnuo Shi
- Department of Microbiology and Immunology, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | - Renee Raudonis
- Department of Microbiology and Immunology, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | - Brendan M. Leung
- Department of Applied Oral Sciences, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | - John R. Rohde
- Department of Microbiology and Immunology, Dalhousie University, Halifax, NS B3H 4R2, Canada
| | - Jost Enninga
- Unité Dynamique des interactions hôtes-pathogènes, Institut Pasteur and CNRS UMR3691, Université de Paris-Cité, 75724 Paris, France
| | - Zhenyu Cheng
- Department of Microbiology and Immunology, Dalhousie University, Halifax, NS B3H 4R2, Canada
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Singh RK, Yoon DS, Mandakhbayar N, Li C, Kurian AG, Lee NH, Lee JH, Kim HW. Diabetic bone regeneration with nanoceria-tailored scaffolds by recapitulating cellular microenvironment: Activating integrin/TGF-β co-signaling of MSCs while relieving oxidative stress. Biomaterials 2022; 288:121732. [PMID: 36031457 DOI: 10.1016/j.biomaterials.2022.121732] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 07/10/2022] [Accepted: 08/04/2022] [Indexed: 11/15/2022]
Abstract
Regenerating defective bone in patients with diabetes mellitus remains a significant challenge due to high blood glucose level and oxidative stress. Here we aim to tackle this issue by means of a drug- and cell-free scaffolding approach. We found the nanoceria decorated on various types of scaffolds (fibrous or 3D-printed one; named nCe-scaffold) could render a therapeutic surface that can recapitulate the microenvironment: modulating oxidative stress while offering a nanotopological cue to regenerating cells. Mesenchymal stem cells (MSCs) recognized the nanoscale (tens of nm) topology of nCe-scaffolds, presenting highly upregulated curvature-sensing membrane protein, integrin set, and adhesion-related molecules. Osteogenic differentiation and mineralization were further significantly enhanced by the nCe-scaffolds. Of note, the stimulated osteogenic potential was identified to be through integrin-mediated TGF-β co-signaling activation. Such MSC-regulatory effects were proven in vivo by the accelerated bone formation in rat calvarium defect model. The nCe-scaffolds further exhibited profound enzymatic and catalytic potential, leading to effectively scavenging reactive oxygen species in vivo. When implanted in diabetic calvarium defect, nCe-scaffolds significantly enhanced early bone regeneration. We consider the currently-exploited nCe-scaffolds can be a promising drug- and cell-free therapeutic means to treat defective tissues like bone in diabetic conditions.
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Affiliation(s)
- Rajendra K Singh
- Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan, 31116, Republic of Korea; Department of Nanobiomedical Science and BK21 NBM Global Research Center for Regenerative Medicine, Dankook University, Cheonan, 31116, Republic of Korea; Mechanobiology Dental Medicine Research Center, Dankook University, Cheonan, 31116, Republic of Korea
| | - Dong Suk Yoon
- Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan, 31116, Republic of Korea; Department of Orthopedic Surgery, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea
| | - Nandin Mandakhbayar
- Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan, 31116, Republic of Korea; Mechanobiology Dental Medicine Research Center, Dankook University, Cheonan, 31116, Republic of Korea
| | - Chengji Li
- Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan, 31116, Republic of Korea; Department of Nanobiomedical Science and BK21 NBM Global Research Center for Regenerative Medicine, Dankook University, Cheonan, 31116, Republic of Korea
| | - Amal George Kurian
- Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan, 31116, Republic of Korea; Department of Nanobiomedical Science and BK21 NBM Global Research Center for Regenerative Medicine, Dankook University, Cheonan, 31116, Republic of Korea
| | - Na-Hyun Lee
- Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan, 31116, Republic of Korea; Mechanobiology Dental Medicine Research Center, Dankook University, Cheonan, 31116, Republic of Korea
| | - Jung-Hwan Lee
- Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan, 31116, Republic of Korea; Department of Nanobiomedical Science and BK21 NBM Global Research Center for Regenerative Medicine, Dankook University, Cheonan, 31116, Republic of Korea; Mechanobiology Dental Medicine Research Center, Dankook University, Cheonan, 31116, Republic of Korea; Department of Biomaterials Science, College of Dentistry, Dankook University, Cheonan, 31116, Republic of Korea; Department of Regenerative Dental Medicine, College of Dentistry, Dankook University, Cheonan, 31116, Republic of Korea; Cell & Matter Institute, Dankook University, Cheonan, 31116, Republic of Korea; UCL Eastman-Korea Dental Medicine Innovation Centre, Dankook University, Cheonan, 31116, Republic of Korea.
| | - Hae-Won Kim
- Institute of Tissue Regeneration Engineering (ITREN), Dankook University, Cheonan, 31116, Republic of Korea; Department of Nanobiomedical Science and BK21 NBM Global Research Center for Regenerative Medicine, Dankook University, Cheonan, 31116, Republic of Korea; Mechanobiology Dental Medicine Research Center, Dankook University, Cheonan, 31116, Republic of Korea; Department of Biomaterials Science, College of Dentistry, Dankook University, Cheonan, 31116, Republic of Korea; Department of Regenerative Dental Medicine, College of Dentistry, Dankook University, Cheonan, 31116, Republic of Korea; Cell & Matter Institute, Dankook University, Cheonan, 31116, Republic of Korea; UCL Eastman-Korea Dental Medicine Innovation Centre, Dankook University, Cheonan, 31116, Republic of Korea.
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7
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Kramer DA, Piper HK, Chen B. WASP family proteins: Molecular mechanisms and implications in human disease. Eur J Cell Biol 2022; 101:151244. [PMID: 35667337 PMCID: PMC9357188 DOI: 10.1016/j.ejcb.2022.151244] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Revised: 05/25/2022] [Accepted: 05/27/2022] [Indexed: 02/08/2023] Open
Abstract
Proteins of the Wiskott-Aldrich syndrome protein (WASP) family play a central role in regulating actin cytoskeletal dynamics in a wide range of cellular processes. Genetic mutations or misregulation of these proteins are tightly associated with many diseases. The WASP-family proteins act by transmitting various upstream signals to their conserved WH2-Central-Acidic (WCA) peptide sequence at the C-terminus, which in turn binds to the Arp2/3 complex to stimulate the formation of branched actin networks at membranes. Despite this common feature, the regulatory mechanisms and cellular functions of distinct WASP-family proteins are very different. Here, we summarize and clarify our current understanding of WASP-family proteins and how disruption of their functions is related to human disease.
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Affiliation(s)
- Daniel A Kramer
- Roy J. Carver Department of Biochemistry, Biophysics & Molecular Biology, Iowa State University, 2437 Pammel Drive, Ames, IA 50011, USA
| | - Hannah K Piper
- Roy J. Carver Department of Biochemistry, Biophysics & Molecular Biology, Iowa State University, 2437 Pammel Drive, Ames, IA 50011, USA
| | - Baoyu Chen
- Roy J. Carver Department of Biochemistry, Biophysics & Molecular Biology, Iowa State University, 2437 Pammel Drive, Ames, IA 50011, USA.
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8
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Mechanisms and Regulation of Cardiac Ca V1.2 Trafficking. Int J Mol Sci 2021; 22:ijms22115927. [PMID: 34072954 PMCID: PMC8197997 DOI: 10.3390/ijms22115927] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 05/28/2021] [Accepted: 05/29/2021] [Indexed: 01/05/2023] Open
Abstract
During cardiac excitation contraction coupling, the arrival of an action potential at the ventricular myocardium triggers voltage-dependent L-type Ca2+ (CaV1.2) channels in individual myocytes to open briefly. The level of this Ca2+ influx tunes the amplitude of Ca2+-induced Ca2+ release from ryanodine receptors (RyR2) on the junctional sarcoplasmic reticulum and thus the magnitude of the elevation in intracellular Ca2+ concentration and ultimately the downstream contraction. The number and activity of functional CaV1.2 channels at the t-tubule dyads dictates the amplitude of the Ca2+ influx. Trafficking of these channels and their auxiliary subunits to the cell surface is thus tightly controlled and regulated to ensure adequate sarcolemmal expression to sustain this critical process. To that end, recent discoveries have revealed the existence of internal reservoirs of preformed CaV1.2 channels that can be rapidly mobilized to enhance sarcolemmal expression in times of acute stress when hemodynamic and metabolic demand increases. In this review, we provide an overview of the current thinking on CaV1.2 channel trafficking dynamics in the heart. We highlight the numerous points of control including the biosynthetic pathway, the endosomal recycling pathway, ubiquitination, and lysosomal and proteasomal degradation pathways, and discuss the effects of β-adrenergic and angiotensin receptor signaling cascades on this process.
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9
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Kapoor T, Dubey P, Shirolikar S, Ray K. An actomyosin clamp assembled by the Amphiphysin-Rho1-Dia/DAAM-Rok pathway reinforces somatic cell membrane folded around spermatid heads. Cell Rep 2021; 34:108918. [PMID: 33789114 DOI: 10.1016/j.celrep.2021.108918] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 12/22/2020] [Accepted: 03/08/2021] [Indexed: 12/14/2022] Open
Abstract
Membrane curvature recruits Bin-Amphiphysin-Rvs (BAR)-domain proteins and induces local F-actin assembly, which further modifies the membrane curvature and dynamics. The downstream molecular pathway in vivo is still unclear. Here, we show that a tubular endomembrane scaffold supported by contractile actomyosin stabilizes the somatic cyst cell membrane folded around rigid spermatid heads during the final stages of sperm maturation in Drosophila testis. The structure resembles an actin "basket" covering the bundle of spermatid heads. Genetic analyses suggest that the actomyosin organization is nucleated exclusively by the formins - Diaphanous and Dishevelled Associated Activator of Morphogenesis (DAAM) - downstream of Rho1, which is recruited by the BAR-domain protein Amphiphysin. Actomyosin activity at the actin basket gathers the spermatid heads into a compact bundle and resists the somatic cell invasion by intruding spermatids. These observations reveal a distinct response mechanism of actin-membrane interactions, which generates a cell-adhesion-like strategy through active clamping.
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Affiliation(s)
- Tushna Kapoor
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai 400005, India
| | - Pankaj Dubey
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai 400005, India
| | - Seema Shirolikar
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai 400005, India
| | - Krishanu Ray
- Department of Biological Sciences, Tata Institute of Fundamental Research, Mumbai 400005, India.
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10
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Leite DM, Matias D, Battaglia G. The Role of BAR Proteins and the Glycocalyx in Brain Endothelium Transcytosis. Cells 2020; 9:E2685. [PMID: 33327645 PMCID: PMC7765129 DOI: 10.3390/cells9122685] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 12/10/2020] [Accepted: 12/11/2020] [Indexed: 12/27/2022] Open
Abstract
Within the brain, endothelial cells lining the blood vessels meticulously coordinate the transport of nutrients, energy metabolites and other macromolecules essential in maintaining an appropriate activity of the brain. While small molecules are pumped across specialised molecular transporters, large macromolecular cargos are shuttled from one side to the other through membrane-bound carriers formed by endocytosis on one side, trafficked to the other side and released by exocytosis. Such a process is collectively known as transcytosis. The brain endothelium is recognised to possess an intricate vesicular endosomal network that mediates the transcellular transport of cargos from blood-to-brain and brain-to-blood. However, mounting evidence suggests that brain endothelial cells (BECs) employ a more direct route via tubular carriers for a fast and efficient transport from the blood to the brain. Here, we compile the mechanism of transcytosis in BECs, in which we highlight intracellular trafficking mediated by tubulation, and emphasise the possible role in transcytosis of the Bin/Amphiphysin/Rvs (BAR) proteins and glycocalyx (GC)-a layer of sugars covering BECs, in transcytosis. Both BAR proteins and the GC are intrinsically associated with cell membranes and involved in the modulation and shaping of these membranes. Hence, we aim to summarise the machinery involved in transcytosis in BECs and highlight an uncovered role of BAR proteins and the GC at the brain endothelium.
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Affiliation(s)
- Diana M. Leite
- Department of Chemistry, University College London, London WC1H 0AJ, UK; (D.M.L.); (D.M.)
- Institute of the Physics and Living Systems, University College London, London WC1H 0AJ, UK
| | - Diana Matias
- Department of Chemistry, University College London, London WC1H 0AJ, UK; (D.M.L.); (D.M.)
- Institute of the Physics and Living Systems, University College London, London WC1H 0AJ, UK
- Samantha Dickson Brain Cancer Unit, Cancer Institute, University College London, London WC1E 06DD, UK
- Cancer Research UK, City of London Centre, London WC1E 06DD, UK
| | - Giuseppe Battaglia
- Department of Chemistry, University College London, London WC1H 0AJ, UK; (D.M.L.); (D.M.)
- Institute of the Physics and Living Systems, University College London, London WC1H 0AJ, UK
- Cancer Research UK, City of London Centre, London WC1E 06DD, UK
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute for Science and Technology (BIST), 08028 Barcelona, Spain
- Catalan Institute for Research and Advanced Studies, 08010 Barcelona, Spain
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11
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Guerra MJ, González‐Jamett AM, Báez‐Matus X, Navarro‐Quezada N, Martínez AD, Neely A, Cárdenas AM. The Ca2+channel subunit CaVβ2a‐subunit down‐regulates voltage‐activated ion current densities by disrupting actin‐dependent traffic in chromaffin cells. J Neurochem 2019; 151:703-715. [DOI: 10.1111/jnc.14851] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 05/01/2019] [Accepted: 08/05/2019] [Indexed: 12/11/2022]
Affiliation(s)
- María J. Guerra
- Facultad de Ciencias, Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia Universidad de Valparaíso Valparaíso Chile
| | - Arlek M. González‐Jamett
- Facultad de Ciencias, Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia Universidad de Valparaíso Valparaíso Chile
| | - Ximena Báez‐Matus
- Facultad de Ciencias, Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia Universidad de Valparaíso Valparaíso Chile
| | - Nieves Navarro‐Quezada
- Facultad de Ciencias, Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia Universidad de Valparaíso Valparaíso Chile
| | - Agustín D. Martínez
- Facultad de Ciencias, Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia Universidad de Valparaíso Valparaíso Chile
| | - Alan Neely
- Facultad de Ciencias, Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia Universidad de Valparaíso Valparaíso Chile
| | - Ana M. Cárdenas
- Facultad de Ciencias, Centro Interdisciplinario de Neurociencia de Valparaíso, Instituto de Neurociencia Universidad de Valparaíso Valparaíso Chile
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12
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SIV-Mediated Synaptic Dysfunction Is Associated with an Increase in Synapsin Site 1 Phosphorylation and Impaired PP2A Activity. J Neurosci 2019; 39:7006-7018. [PMID: 31270156 DOI: 10.1523/jneurosci.0178-19.2019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2019] [Revised: 05/31/2019] [Accepted: 06/22/2019] [Indexed: 11/21/2022] Open
Abstract
Although the reduction of viral loads in people with HIV undergoing combination antiretroviral therapy has mitigated AIDS-related symptoms, the prevalence of neurological impairments has remained unchanged. HIV-associated CNS dysfunction includes impairments in memory, attention, memory processing, and retrieval. Here, we show a significant site-specific increase in the phosphorylation of Syn I serine 9, site 1, in the frontal cortex lysates and synaptosome preparations of male rhesus macaques infected with simian immunodeficiency virus (SIV) but not in uninfected or SIV-infected antiretroviral therapy animals. Furthermore, we found that a lower protein phosphatase 2A (PP2A) activity, a phosphatase responsible for Syn I (S9) dephosphorylation, is primarily associated with the higher S9 phosphorylation in the frontal cortex of SIV-infected macaques. Comparison of brain sections confirmed higher Syn I (S9) in the frontal cortex and greater coexpression of Syn I and PP2A A subunit, which was observed as perinuclear aggregates in the somata of the frontal cortex of SIV-infected macaques. Synaptosomes from SIV-infected animals were physiologically tested using a synaptic vesicle endocytosis assay and FM4-64 dye showing a significantly higher baseline depolarization levels in synaptosomes of SIV+-infected than uninfected control or antiretroviral therapy animals. A PP2A-activating FDA-approved drug, FTY720, decreased the higher synaptosome depolarization in SIV-infected animals. Our results suggest that an impaired distribution and lower activity of serine/threonine phosphatases in the context of HIV infection may cause an indirect effect on the phosphorylation levels of essential proteins involving in synaptic transmission, supporting the occurrence of specific impairments in the synaptic activity during SIV infection.SIGNIFICANCE STATEMENT Even with antiretroviral therapy, neurocognitive deficits, including impairments in attention, memory processing, and retrieval, are still major concerns in people living with HIV. Here, we used the rhesus macaque simian immunodeficiency virus model with and without antiretroviral therapy to study the dynamics of phosphorylation of key amino acid residues of synapsin I, which critically impacts synaptic vesicle function. We found a significant increase in synapsin I phosphorylation at serine 9, which was driven by dysfunction of serine/threonine protein phosphatase 2A in the nerve terminals. Our results suggest that an impaired distribution and lower activity of serine/threonine phosphatases in the context of HIV infection may cause an indirect effect on the phosphorylation levels of essential proteins involved in synaptic transmission.
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13
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Rampérez A, Bartolomé-Martín D, García-Pascual A, Sánchez-Prieto J, Torres M. Photoconversion of FM1-43 Reveals Differences in Synaptic Vesicle Recycling and Sensitivity to Pharmacological Disruption of Actin Dynamics in Individual Synapses. ACS Chem Neurosci 2019; 10:2045-2059. [PMID: 30763065 DOI: 10.1021/acschemneuro.8b00712] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
The cycling of synaptic vesicles ensures that neurons can communicate adequately through their synapses on repeated occasions when activity is sustained, and several steps in this cycle are modulated by actin. The effects of pharmacological stabilization of actin with jasplakinolide or its depolymerization with latrunculin A was assessed on the synaptic vesicle cycle at individual boutons of cerebellar granule cells, using FM1-43 imaging to track vesicle recycling and its photoconversion to specifically label recycled organelles. Remarkable differences in the recycling capacity of individual boutons are evident, and their dependence on the actin cytoskeleton for recycling is clear. Disrupting actin dynamics causes a loss of functional boutons, and while this indicates that exo/endocytotic cycling in boutons is fully dependent on such events, this dependence is only partial in other boutons. Indeed, exocytosis and vesicle trafficking are impaired significantly by stabilizing or depolymerizing actin, whereas repositioning recycled vesicles at the active zone seems to be dependent on actin polymerization alone. These findings support the hypothesis that different steps of synaptic vesicle cycling depend on actin dynamics and that such dependence varies among individual boutons.
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Affiliation(s)
- Alberto Rampérez
- Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid 28040, Spain
| | - David Bartolomé-Martín
- Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid 28040, Spain
| | - Angeles García-Pascual
- Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid 28040, Spain
| | - Jose Sánchez-Prieto
- Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid 28040, Spain
| | - Magdalena Torres
- Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid 28040, Spain
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14
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BAR domain proteins-a linkage between cellular membranes, signaling pathways, and the actin cytoskeleton. Biophys Rev 2018; 10:1587-1604. [PMID: 30456600 DOI: 10.1007/s12551-018-0467-7] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Accepted: 10/17/2018] [Indexed: 12/23/2022] Open
Abstract
Actin filament assembly typically occurs in association with cellular membranes. A large number of proteins sit at the interface between actin networks and membranes, playing diverse roles such as initiation of actin polymerization, modulation of membrane curvature, and signaling. Bin/Amphiphysin/Rvs (BAR) domain proteins have been implicated in all of these functions. The BAR domain family of proteins comprises a diverse group of multi-functional effectors, characterized by their modular architecture. In addition to the membrane-curvature sensing/inducing BAR domain module, which also mediates antiparallel dimerization, most contain auxiliary domains implicated in protein-protein and/or protein-membrane interactions, including SH3, PX, PH, RhoGEF, and RhoGAP domains. The shape of the BAR domain itself varies, resulting in three major subfamilies: the classical crescent-shaped BAR, the more extended and less curved F-BAR, and the inverse curvature I-BAR subfamilies. Most members of this family have been implicated in cellular functions that require dynamic remodeling of the actin cytoskeleton, such as endocytosis, organelle trafficking, cell motility, and T-tubule biogenesis in muscle cells. Here, we review the structure and function of mammalian BAR domain proteins and the many ways in which they are interconnected with the actin cytoskeleton.
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15
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Somasundaram A, Taraska JW. Local protein dynamics during microvesicle exocytosis in neuroendocrine cells. Mol Biol Cell 2018; 29:1891-1903. [PMID: 29874123 PMCID: PMC6085826 DOI: 10.1091/mbc.e17-12-0716] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Calcium-triggered exocytosis is key to many physiological processes, including neurotransmitter and hormone release by neurons and endocrine cells. Dozens of proteins regulate exocytosis, yet the temporal and spatial dynamics of these factors during vesicle fusion remain unclear. Here we use total internal reflection fluorescence microscopy to visualize local protein dynamics at single sites of exocytosis of small synaptic-like microvesicles in live cultured neuroendocrine PC12 cells. We employ two-color imaging to simultaneously observe membrane fusion (using vesicular acetylcholine ACh transporter tagged to pHluorin) and the dynamics of associated proteins at the moments surrounding exocytosis. Our experiments show that many proteins, including the SNAREs syntaxin1 and VAMP2, the SNARE modulator tomosyn, and Rab proteins, are preclustered at fusion sites and rapidly lost at fusion. The ATPase N-ethylmaleimide–sensitive factor is locally recruited at fusion. Interestingly, the endocytic Bin-Amphiphysin-Rvs domain–containing proteins amphiphysin1, syndapin2, and endophilins are dynamically recruited to fusion sites and slow the loss of vesicle membrane-bound cargo from fusion sites. A similar effect on vesicle membrane protein dynamics was seen with the overexpression of the GTPases dynamin1 and dynamin2. These results suggest that proteins involved in classical clathrin-mediated endocytosis can regulate exocytosis of synaptic-like microvesicles. Our findings provide insights into the dynamics, assembly, and mechanistic roles of many key factors of exocytosis and endocytosis at single sites of microvesicle fusion in live cells.
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Affiliation(s)
- Agila Somasundaram
- Laboratory of Molecular Biophysics, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892
| | - Justin W Taraska
- Laboratory of Molecular Biophysics, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892
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16
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Candiello E, Mishra R, Schmidt B, Jahn O, Schu P. Differential regulation of synaptic AP-2/clathrin vesicle uncoating in synaptic plasticity. Sci Rep 2017; 7:15781. [PMID: 29150658 PMCID: PMC5694008 DOI: 10.1038/s41598-017-16055-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 10/24/2017] [Indexed: 11/09/2022] Open
Abstract
AP-1/σ1B-deficiency causes X-linked intellectual disability. AP-1/σ1B -/- mice have impaired synaptic vesicle recycling, fewer synaptic vesicles and enhanced endosome maturation mediated by AP-1/σ1A. Despite defects in synaptic vesicle recycling synapses contain two times more endocytic AP-2 clathrin-coated vesicles. We demonstrate increased formation of two classes of AP-2/clathrin coated vesicles. One which uncoats readily and a second with a stabilised clathrin coat. Coat stabilisation is mediated by three molecular mechanisms: reduced recruitment of Hsc70 and synaptojanin1 and enhanced μ2/AP-2 phosphorylation and activation. Stabilised AP-2 vesicles are enriched in the structural active zone proteins Git1 and stonin2 and synapses contain more Git1. Endocytosis of the synaptic vesicle exocytosis regulating Munc13 isoforms are differentially effected. Regulation of synaptic protein endocytosis by the differential stability of AP-2/clathrin coats is a novel molecular mechanism of synaptic plasticity.
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Affiliation(s)
- Ermes Candiello
- Department of Cellular Biochemistry, University Medical Center Goettingen, Georg-August-University Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
| | - Ratnakar Mishra
- Department of Cellular Biochemistry, University Medical Center Goettingen, Georg-August-University Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
| | - Bernhard Schmidt
- Department of Cellular Biochemistry, University Medical Center Goettingen, Georg-August-University Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
| | - Olaf Jahn
- The Max-Planck-Institute for Experimental Medicine, Proteomics, Hermann-Rein-Str. 3, 37073, Göttingen, Germany
| | - Peter Schu
- Department of Cellular Biochemistry, University Medical Center Goettingen, Georg-August-University Göttingen, Humboldtallee 23, 37073, Göttingen, Germany.
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17
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Dräger NM, Nachman E, Winterhoff M, Brühmann S, Shah P, Katsinelos T, Boulant S, Teleman AA, Faix J, Jahn TR. Bin1 directly remodels actin dynamics through its BAR domain. EMBO Rep 2017; 18:2051-2066. [PMID: 28893863 DOI: 10.15252/embr.201744137] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2017] [Revised: 08/07/2017] [Accepted: 08/08/2017] [Indexed: 11/09/2022] Open
Abstract
Endocytic processes are facilitated by both curvature-generating BAR-domain proteins and the coordinated polymerization of actin filaments. Under physiological conditions, the N-BAR protein Bin1 has been shown to sense and curve membranes in a variety of cellular processes. Recent studies have identified Bin1 as a risk factor for Alzheimer's disease, although its possible pathological function in neurodegeneration is currently unknown. Here, we report that Bin1 not only shapes membranes, but is also directly involved in actin binding through its BAR domain. We observed a moderate actin bundling activity by human Bin1 and describe its ability to stabilize actin filaments against depolymerization. Moreover, Bin1 is also involved in stabilizing tau-induced actin bundles, which are neuropathological hallmarks of Alzheimer's disease. We also provide evidence for this effect in vivo, where we observed that downregulation of Bin1 in a Drosophila model of tauopathy significantly reduces the appearance of tau-induced actin inclusions. Together, these findings reveal the ability of Bin1 to modify actin dynamics and provide a possible mechanistic connection between Bin1 and tau-induced pathobiological changes of the actin cytoskeleton.
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Affiliation(s)
- Nina M Dräger
- Proteostasis in Neurodegenerative Disease (B180), Schaller Research Group at the University of Heidelberg and DKFZ, Heidelberg, Germany
| | - Eliana Nachman
- Proteostasis in Neurodegenerative Disease (B180), Schaller Research Group at the University of Heidelberg and DKFZ, Heidelberg, Germany.,German Cancer Research Center (DKFZ), DKFZ-ZMBH Alliance, Center for Molecular Biology of Heidelberg University (ZMBH), Heidelberg, Germany
| | - Moritz Winterhoff
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Stefan Brühmann
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Pranav Shah
- Schaller Research Group at CellNetworks, Department of Infectious Diseases, Virology, Heidelberg University, Heidelberg, Germany.,Cellular polarity and viral infection (F140), German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Taxiarchis Katsinelos
- Proteostasis in Neurodegenerative Disease (B180), Schaller Research Group at the University of Heidelberg and DKFZ, Heidelberg, Germany
| | - Steeve Boulant
- Schaller Research Group at CellNetworks, Department of Infectious Diseases, Virology, Heidelberg University, Heidelberg, Germany.,Cellular polarity and viral infection (F140), German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Aurelio A Teleman
- Signal Transduction in Cancer and Metabolism (B140), German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Jan Faix
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Thomas R Jahn
- Proteostasis in Neurodegenerative Disease (B180), Schaller Research Group at the University of Heidelberg and DKFZ, Heidelberg, Germany
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18
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Masuda Y, Yokose S, Sakagami H. Gene Expression Analysis of Cultured Rat-Endothelial Cells after Nd:YAG Laser Irradiation by Affymetrix GeneChip Array. ACTA ACUST UNITED AC 2017; 31:51-54. [PMID: 28064220 DOI: 10.21873/invivo.11024] [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: 10/17/2016] [Revised: 12/16/2016] [Accepted: 12/21/2016] [Indexed: 12/14/2022]
Abstract
Endothelial cells and dental pulp cells enhance osteo-/odontogenic and angiogenic differentiation. In our previous study, rat pulp cells migrated to Nd:YAG laser-irradiated endothelial cells in an insert cell culture system. The purpose of this study was to examine the possible changes in the gene expression of cultured rat aortic endothelial cells after Nd:YAG laser irradiation using affymetrix GeneChip Array. Total RNA was extracted from the cells at 5 h after laser irradiation. Gene expressions were evaluated by DNA array chip. Up-regulated genes were related to cell migration and cell structure (membrane stretch, actin regulation and junctional complexes), neurotransmission and inflammation. Heat-shock 70 kDa protein (Hsp70) was related to the development of tooth germ. This study offers candidate genes for understanding the relationship between the laser-stimulated endothelial cells and dental pulp cells.
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Affiliation(s)
- Yoshiko Masuda
- Meikai Pharmaco-Medical Laboratory (MPL), Meikai University School of Dentistry, Saitama, Japan
| | - Satoshi Yokose
- Division of Endodontics and Operative, Meikai University School of Dentistry, Saitama, Japan
| | - Hiroshi Sakagami
- Meikai Pharmaco-Medical Laboratory (MPL), Meikai University School of Dentistry, Saitama, Japan.,Division of Pharmacology, Meikai University School of Dentistry, Saitama, Japan
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19
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Kong Y, Janssen BJC, Malinauskas T, Vangoor VR, Coles CH, Kaufmann R, Ni T, Gilbert RJC, Padilla-Parra S, Pasterkamp RJ, Jones EY. Structural Basis for Plexin Activation and Regulation. Neuron 2016; 91:548-60. [PMID: 27397516 PMCID: PMC4980550 DOI: 10.1016/j.neuron.2016.06.018] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Revised: 05/11/2016] [Accepted: 06/07/2016] [Indexed: 12/17/2022]
Abstract
Class A plexins (PlxnAs) act as semaphorin receptors and control diverse aspects of nervous system development and plasticity, ranging from axon guidance and neuron migration to synaptic organization. PlxnA signaling requires cytoplasmic domain dimerization, but extracellular regulation and activation mechanisms remain unclear. Here we present crystal structures of PlxnA (PlxnA1, PlxnA2, and PlxnA4) full ectodomains. Domains 1-9 form a ring-like conformation from which the C-terminal domain 10 points away. All our PlxnA ectodomain structures show autoinhibitory, intermolecular "head-to-stalk" (domain 1 to domain 4-5) interactions, which are confirmed by biophysical assays, live cell fluorescence microscopy, and cell-based and neuronal growth cone collapse assays. This work reveals a 2-fold role of the PlxnA ectodomains: imposing a pre-signaling autoinhibitory separation for the cytoplasmic domains via intermolecular head-to-stalk interactions and supporting dimerization-based PlxnA activation upon ligand binding. More generally, our data identify a novel molecular mechanism for preventing premature activation of axon guidance receptors.
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Affiliation(s)
- Youxin Kong
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Bert J C Janssen
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Tomas Malinauskas
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Vamshidhar R Vangoor
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Charlotte H Coles
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Rainer Kaufmann
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom; Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Tao Ni
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Robert J C Gilbert
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Sergi Padilla-Parra
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - R Jeroen Pasterkamp
- Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, The Netherlands.
| | - E Yvonne Jones
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom.
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20
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Fluvoxamine, an anti-depressant, inhibits human glioblastoma invasion by disrupting actin polymerization. Sci Rep 2016; 6:23372. [PMID: 26988603 PMCID: PMC4796892 DOI: 10.1038/srep23372] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 03/02/2016] [Indexed: 12/31/2022] Open
Abstract
Glioblastoma multiforme (GBM) is the most common malignant brain tumor with a median survival time about one year. Invasion of GBM cells into normal brain is the major cause of poor prognosis and requires dynamic reorganization of the actin cytoskeleton, which includes lamellipodial protrusions, focal adhesions, and stress fibers at the leading edge of GBM. Therefore, we hypothesized that inhibitors of actin polymerization can suppress GBM migration and invasion. First, we adopted a drug repositioning system for screening with a pyrene-actin-based actin polymerization assay and identified fluvoxamine, a clinically used antidepressant. Fluvoxamine, selective serotonin reuptake inhibitor, was a potent inhibitor of actin polymerization and confirmed as drug penetration through the blood-brain barrier (BBB) and accumulation of whole brain including brain tumor with no drug toxicity. Fluvoxamine inhibited serum-induced ruffle formation, cell migration, and invasion of human GBM and glioma stem cells in vitro by suppressing both FAK and Akt/mammalian target of rapamycin signaling. Daily treatment of athymic mice bearing human glioma-initiating cells with fluvoxamine blocked tumor cell invasion and prolonged the survival with almost same dose of anti-depressant effect. In conclusion, fluvoxamine is a promising anti-invasive treatment against GBM with reliable approach.
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21
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Falcone S, Roman W, Hnia K, Gache V, Didier N, Lainé J, Auradé F, Marty I, Nishino I, Charlet-Berguerand N, Romero NB, Marazzi G, Sassoon D, Laporte J, Gomes ER. N-WASP is required for Amphiphysin-2/BIN1-dependent nuclear positioning and triad organization in skeletal muscle and is involved in the pathophysiology of centronuclear myopathy. EMBO Mol Med 2015; 6:1455-75. [PMID: 25262827 PMCID: PMC4237471 DOI: 10.15252/emmm.201404436] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Mutations in amphiphysin-2/BIN1, dynamin 2, and myotubularin are associated with centronuclear myopathy (CNM), a muscle disorder characterized by myofibers with atypical central nuclear positioning and abnormal triads. Mis-splicing of amphiphysin-2/BIN1 is also associated with myotonic dystrophy that shares histopathological hallmarks with CNM. How amphiphysin-2 orchestrates nuclear positioning and triad organization and how CNM-associated mutations lead to muscle dysfunction remains elusive. We find that N-WASP interacts with amphiphysin-2 in myofibers and that this interaction and N-WASP distribution are disrupted by amphiphysin-2 CNM mutations. We establish that N-WASP functions downstream of amphiphysin-2 to drive peripheral nuclear positioning and triad organization during myofiber formation. Peripheral nuclear positioning requires microtubule/Map7/Kif5b-dependent distribution of nuclei along the myofiber and is driven by actin and nesprins. In adult myofibers, N-WASP and amphiphysin-2 are only involved in the maintenance of triad organization but not in the maintenance of peripheral nuclear positioning. Importantly, we confirmed that N-WASP distribution is disrupted in CNM and myotonic dystrophy patients. Our results support a role for N-WASP in amphiphysin-2-dependent nuclear positioning and triad organization and in CNM and myotonic dystrophy pathophysiology.
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Affiliation(s)
- Sestina Falcone
- Myology Group, UMR S 787 INSERM, Université Pierre et Marie Curie Paris 6, Paris, France Institut de Myologie, Groupe Hospitalier Pitié-Salpêtrière, Paris, France
| | - William Roman
- Myology Group, UMR S 787 INSERM, Université Pierre et Marie Curie Paris 6, Paris, France
| | - Karim Hnia
- IGBMC-CNRS, UMR 7104 INSERM U964, Illkirch, France
| | - Vincent Gache
- Myology Group, UMR S 787 INSERM, Université Pierre et Marie Curie Paris 6, Paris, France Institut de Myologie, Groupe Hospitalier Pitié-Salpêtrière, Paris, France
| | - Nathalie Didier
- Myology Group, UMR S 787 INSERM, Université Pierre et Marie Curie Paris 6, Paris, France
| | - Jeanne Lainé
- Institut de Myologie, Groupe Hospitalier Pitié-Salpêtrière, Paris, France
| | - Frederic Auradé
- Myology Group, UMR S 787 INSERM, Université Pierre et Marie Curie Paris 6, Paris, France
| | - Isabelle Marty
- INSERM U836, Grenoble Institut des Neurosciences, Equipe Muscle et Pathologies, Grenoble, France
| | - Ichizo Nishino
- National Center of Neurology and Psychiatry, Tokyo, Japan
| | | | | | - Giovanna Marazzi
- Myology Group, UMR S 787 INSERM, Université Pierre et Marie Curie Paris 6, Paris, France
| | - David Sassoon
- Myology Group, UMR S 787 INSERM, Université Pierre et Marie Curie Paris 6, Paris, France
| | | | - Edgar R Gomes
- Myology Group, UMR S 787 INSERM, Université Pierre et Marie Curie Paris 6, Paris, France Institut de Myologie, Groupe Hospitalier Pitié-Salpêtrière, Paris, France Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Lisboa, Portugal
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22
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Zhao Y, Ren J, Padilla-Parra S, Fry EE, Stuart DI. Lysosome sorting of β-glucocerebrosidase by LIMP-2 is targeted by the mannose 6-phosphate receptor. Nat Commun 2014; 5:4321. [PMID: 25027712 PMCID: PMC4104448 DOI: 10.1038/ncomms5321] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Accepted: 06/05/2014] [Indexed: 01/25/2023] Open
Abstract
The integral membrane protein LIMP-2 has been a paradigm for mannose 6-phosphate receptor (MPR) independent lysosomal targeting, binding to β-glucocerebrosidase (β-GCase) and directing it to the lysosome, before dissociating in the late-endosomal/lysosomal compartments. Here we report structural results illuminating how LIMP-2 binds and releases β-GCase according to changes in pH, via a histidine trigger, and suggesting that LIMP-2 localizes the ceramide portion of the substrate adjacent to the β-GCase catalytic site. Remarkably, we find that LIMP-2 bears P-Man9GlcNAc2 covalently attached to residue N325, and that it binds MPR, via mannose 6-phosphate, with a similar affinity to that observed between LIMP-2 and β-GCase. The binding sites for β-GCase and the MPR are functionally separate, so that a stable ternary complex can be formed. By fluorescence lifetime imaging microscopy, we also demonstrate that LIMP-2 interacts with MPR in living cells. These results revise the accepted view of LIMP-2-β-GCase lysosomal targeting.
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Affiliation(s)
- Yuguang Zhao
- Division of Structural Biology, University of Oxford, The Henry Wellcome Building for Genomic Medicine, Headington, Oxford OX3 7BN, UK
- These authors contributed equally to this work
| | - Jingshan Ren
- Division of Structural Biology, University of Oxford, The Henry Wellcome Building for Genomic Medicine, Headington, Oxford OX3 7BN, UK
- These authors contributed equally to this work
| | - Sergi Padilla-Parra
- Division of Structural Biology, University of Oxford, The Henry Wellcome Building for Genomic Medicine, Headington, Oxford OX3 7BN, UK
| | - Elizabeth E. Fry
- Division of Structural Biology, University of Oxford, The Henry Wellcome Building for Genomic Medicine, Headington, Oxford OX3 7BN, UK
| | - David I. Stuart
- Division of Structural Biology, University of Oxford, The Henry Wellcome Building for Genomic Medicine, Headington, Oxford OX3 7BN, UK
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23
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Hong T, Yang H, Zhang SS, Cho HC, Kalashnikova M, Sun B, Zhang H, Bhargava A, Grabe M, Olgin J, Gorelik J, Marbán E, Jan LY, Shaw RM. Cardiac BIN1 folds T-tubule membrane, controlling ion flux and limiting arrhythmia. Nat Med 2014; 20:624-32. [PMID: 24836577 PMCID: PMC4048325 DOI: 10.1038/nm.3543] [Citation(s) in RCA: 172] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Accepted: 03/24/2014] [Indexed: 11/08/2022]
Abstract
Cardiomyocyte T tubules are important for regulating ion flux. Bridging integrator 1 (BIN1) is a T-tubule protein associated with calcium channel trafficking that is downregulated in failing hearts. Here we find that cardiac T tubules normally contain dense protective inner membrane folds that are formed by a cardiac isoform of BIN1. In mice with cardiac Bin1 deletion, T-tubule folding is decreased, which does not change overall cardiomyocyte morphology but leads to free diffusion of local extracellular calcium and potassium ions, prolonging action-potential duration and increasing susceptibility to ventricular arrhythmias. We also found that T-tubule inner folds are rescued by expression of the BIN1 isoform BIN1+13+17, which promotes N-WASP-dependent actin polymerization to stabilize the T-tubule membrane at cardiac Z discs. BIN1+13+17 recruits actin to fold the T-tubule membrane, creating a 'fuzzy space' that protectively restricts ion flux. When the amount of the BIN1+13+17 isoform is decreased, as occurs in acquired cardiomyopathy, T-tubule morphology is altered, and arrhythmia can result.
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Affiliation(s)
- TingTing Hong
- Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Huanghe Yang
- Departments of Physiology, Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, USA
| | - Shan-Shan Zhang
- Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Hee Cheol Cho
- Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Mariya Kalashnikova
- Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Baiming Sun
- Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Hao Zhang
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, CA, USA
| | - Anamika Bhargava
- Imperial Center for Translational and Experimental Medicine, Imperial College, London, UK
| | - Michael Grabe
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, CA, USA
| | - Jeffrey Olgin
- Division of Cardiology, Department of Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Julia Gorelik
- Imperial Center for Translational and Experimental Medicine, Imperial College, London, UK
| | - Eduardo Marbán
- Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Lily Y. Jan
- Departments of Physiology, Biochemistry and Biophysics, University of California San Francisco, San Francisco, CA, USA
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, CA, USA
- Howard Hughes Medical Institute, USA
| | - Robin M. Shaw
- Cedars-Sinai Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA, USA
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Roybal KT, Sinai P, Verkade P, Murphy RF, Wülfing C. The actin-driven spatiotemporal organization of T-cell signaling at the system scale. Immunol Rev 2014; 256:133-47. [PMID: 24117818 DOI: 10.1111/imr.12103] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
T cells are activated through interaction with antigen-presenting cells (APCs). During activation, receptors and signaling intermediates accumulate in diverse spatiotemporal distributions. These distributions control the probability of signaling interactions and thus govern information flow through the signaling system. Spatiotemporally resolved system-scale investigation of signaling can extract the regulatory information thus encoded, allowing unique insight into the control of T-cell function. Substantial technical challenges exist, and these are briefly discussed herein. While much of the work assessing T-cell spatiotemporal organization uses planar APC substitutes, we focus here on B-cell APCs with often stark differences. Spatiotemporal signaling distributions are driven by cell biologically distinct structures, a large protein assembly at the interface center, a large invagination, the actin-supported interface periphery as extended by smaller individual lamella, and a newly discovered whole-interface actin-driven lamellum. The more than 60 elements of T-cell activation studied to date are dynamically distributed between these structures, generating a complex organization of the signaling system. Signal initiation and core signaling prefer the interface center, while signal amplification is localized in the transient lamellum. Actin dynamics control signaling distributions through regulation of the underlying structures and drive a highly undulating T-cell/APC interface that imposes substantial constraints on T-cell organization. We suggest that the regulation of actin dynamics, by controlling signaling distributions and membrane topology, is an important rheostat of T-cell signaling.
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Affiliation(s)
- Kole T Roybal
- Department of Immunology, UT Southwestern Medical Center, Dallas, TX, USA
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Wolf M, Zimmermann AM, Görlich A, Gurniak CB, Sassoè-Pognetto M, Friauf E, Witke W, Rust MB. ADF/Cofilin Controls Synaptic Actin Dynamics and Regulates Synaptic Vesicle Mobilization and Exocytosis. Cereb Cortex 2014; 25:2863-75. [PMID: 24770705 DOI: 10.1093/cercor/bhu081] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Actin is a regulator of synaptic vesicle mobilization and exocytosis, but little is known about the mechanisms that regulate actin at presynaptic terminals. Genetic data on LIMK1, a negative regulator of actin-depolymerizing proteins of the ADF/cofilin family, suggest a role for ADF/cofilin in presynaptic function. However, synapse physiology is fully preserved upon genetic ablation of ADF in mice, and n-cofilin mutant mice display defects in postsynaptic plasticity, but not in presynaptic function. One explanation for this phenomenon is overlapping functions of ADF and n-cofilin in presynaptic physiology. Here, we tested this hypothesis and genetically removed ADF together with n-cofilin from synapses. In double mutants for ADF and n-cofilin, synaptic actin dynamics was impaired and more severely affected than in single mutants. The resulting cytoskeletal defects heavily affected the organization, mobilization, and exocytosis of synaptic vesicles in hippocampal CA3-CA1 synapses. Our data for the first time identify overlapping functions for ADF and n-cofilin in presynaptic physiology and vesicle trafficking. We conclude that n-cofilin is a limiting factor in postsynaptic plasticity, a function which cannot be substituted by ADF. On the presynaptic side, the presence of either ADF or n-cofilin is sufficient to control actin remodeling during vesicle release.
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Affiliation(s)
- Michael Wolf
- Department of Biology, Neurobiology/Neurophysiology Group, University of Kaiserslautern, Kaiserslautern 67663, Germany
| | - Anika-Maria Zimmermann
- Department of Biology, Neurobiology/Neurophysiology Group, University of Kaiserslautern, Kaiserslautern 67663, Germany
| | - Andreas Görlich
- Department of Biology, Neurobiology/Neurophysiology Group, University of Kaiserslautern, Kaiserslautern 67663, Germany Current address: Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | | | - Marco Sassoè-Pognetto
- Department of Anatomy, Pharmacology and Forensic Medicine and National Institute of Neuroscience-Italy, University of Turin, Turin 10126, Italy
| | - Eckhard Friauf
- Animal Physiology Group, University of Kaiserslautern, Kaiserslautern 67663, Germany
| | - Walter Witke
- Institute of Genetics, University of Bonn, Bonn 53115, Germany
| | - Marco B Rust
- Department of Biology, Neurobiology/Neurophysiology Group, University of Kaiserslautern, Kaiserslautern 67663, Germany Institute of Physiological Chemistry, University of Marburg, 35043 Marburg, Germany
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26
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Amphiphysin 2 (BIN1) in physiology and diseases. J Mol Med (Berl) 2014; 92:453-63. [DOI: 10.1007/s00109-014-1138-1] [Citation(s) in RCA: 102] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2013] [Revised: 02/11/2014] [Accepted: 02/17/2014] [Indexed: 12/15/2022]
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Idrissi FZ, Geli MI. Zooming in on the molecular mechanisms of endocytic budding by time-resolved electron microscopy. Cell Mol Life Sci 2014; 71:641-57. [PMID: 24002236 PMCID: PMC11113444 DOI: 10.1007/s00018-013-1452-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Revised: 07/17/2013] [Accepted: 08/08/2013] [Indexed: 12/31/2022]
Abstract
Endocytic budding implies the remodeling of a plasma membrane portion from a flat sheet to a closed vesicle. Clathrin- and actin-mediated endocytosis in yeast has proven a very powerful model to study this process, with more than 60 evolutionarily conserved proteins involved in fashioning primary endocytic vesicles. Major progress in the field has been made during the last decades by defining the sequential recruitment of the endocytic machinery at the cell cortex using live-cell fluorescence microscopy. Higher spatial resolution has been recently achieved by developing time-resolved electron microscopy methods, allowing for the first time the visualization of changes in the plasma membrane shape, coupled to the dynamics of the endocytic machinery. Here, we highlight these advances and review recent findings from yeast and mammals that have increased our understanding of where and how endocytic proteins may apply force to remodel the plasma membrane during different stages of the process.
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Affiliation(s)
- Fatima-Zahra Idrissi
- Department of Cell Biology, Instituto de Biología Molecular de Barcelona (CSIC), Baldiri i Reixac 15, 08028, Barcelona, Spain,
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N'-[4-(dipropylamino)benzylidene]-2-hydroxybenzohydrazide is a dynamin GTPase inhibitor that suppresses cancer cell migration and invasion by inhibiting actin polymerization. Biochem Biophys Res Commun 2013; 443:511-7. [PMID: 24316215 DOI: 10.1016/j.bbrc.2013.11.118] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2013] [Accepted: 11/29/2013] [Indexed: 11/24/2022]
Abstract
Dynasore, a specific dynamin GTPase inhibitor, suppresses lamellipodia formation and cancer cell invasion by destabilizing actin filaments. In search for novel dynamin inhibitors that suppress actin dynamics more efficiently, dynasore analogues were screened. N'-[4-(dipropylamino)benzylidene]-2-hydroxybenzohydrazide (DBHA) markedly reduced in vitro actin polymerization, and dose-dependently inhibited phosphatidylserine-stimulated dynamin GTPase activity. DBHA significantly suppressed both the recruitment of dynamin 2 to the leading edge in U2OS cells and ruffle formation in H1299 cells. Furthermore, DBHA suppressed both the migration and invasion of H1299 cells by approximately 70%. Furthermore, intratumoral DBHA delivery significantly repressed tumor growth. DBHA was much less cytotoxic than dynasore. These results strongly suggest that DBHA inhibits dynamin-dependent actin polymerization by altering the interactions between dynamin and lipid membranes. DBHA and its derivative may be potential candidates for potent anti-cancer drugs.
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Leray A, Padilla-Parra S, Roul J, Héliot L, Tramier M. Spatio-Temporal Quantification of FRET in living cells by fast time-domain FLIM: a comparative study of non-fitting methods [corrected]. PLoS One 2013; 8:e69335. [PMID: 23874948 PMCID: PMC3715500 DOI: 10.1371/journal.pone.0069335] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Accepted: 06/09/2013] [Indexed: 11/30/2022] Open
Abstract
Förster Resonance Energy Transfer (FRET) measured with Fluorescence Lifetime Imaging Microscopy (FLIM) is a powerful technique to investigate spatio-temporal regulation of protein-protein interactions in living cells. When using standard fitting methods to analyze time domain FLIM, the correct estimation of the FRET parameters requires a high number of photons and therefore long acquisition times which are incompatible with the observation of dynamic protein-protein interactions. Recently, non-fitting strategies have been developed for the analysis of FLIM images: the polar plot or "phasor" and the minimal fraction of interacting donor mfD . We propose here a novel non-fitting strategy based on the calculation of moments. We then compare the performance of these three methods when shortening the acquisition time: either by reducing the number of counted photons N or the number of temporal channels Nch , which is particularly adapted for the original fast-FLIM prototype presented in this work that employs the time gated approach. Based on theoretical calculations, Monte Carlo simulations and experimental data, we determine the domain of validity of each method. We thus demonstrate that the polar approach remains accurate for a large range of conditions (low N, Nch or small fractions of interacting donor fD ). The validity domain of the moments method is more restricted (not applicable when fD <0.25 or when Nch = 4) but it is more precise than the polar approach. We also demonstrate that the mfD is robust in all conditions and it is the most precise strategy; although it does not strictly provide the fraction of interacting donor. We show using the fast-FLIM prototype (with an acquisition rate up to 1 Hz) that these non-fitting strategies are very powerful for on-line analysis on a standard computer and thus for quantifying automatically the spatio-temporal activation of Rac-GTPase in living cells by FRET.
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Affiliation(s)
- Aymeric Leray
- Institut de Recherche Interdisciplinaire, USR 3078 CNRS, Université de Lille-Nord de France, Biophotonique Cellulaire Fonctionnelle, Villeneuve d'Ascq, France.
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Stabilization of actin bundles by a dynamin 1/cortactin ring complex is necessary for growth cone filopodia. J Neurosci 2013; 33:4514-26. [PMID: 23467367 DOI: 10.1523/jneurosci.2762-12.2013] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Dynamin GTPase, a key molecule in endocytosis, mechanically severs the invaginated membrane upon GTP hydrolysis. Dynamin functions also in regulating actin cytoskeleton, but the mechanisms are yet to be defined. Here we show that dynamin 1, a neuronal isoform of dynamin, and cortactin form ring complexes, which twine around F-actin bundles and stabilize them. By negative-staining EM, dynamin 1-cortactin complexes appeared as "open" or "closed" rings depending on guanine nucleotide conditions. By pyrene actin assembly assay, dynamin 1 stimulated actin assembly in mouse brain cytosol. In vitro incubation of F-actin with both dynamin 1 and cortactin led to the formation of long and thick actin bundles, on which dynamin 1 and cortactin were periodically colocalized in puncta. A depolymerization assay revealed that dynamin 1 and cortactin increased the stability of actin bundles, most prominently in the presence of GTP. In rat cortical neurons and human neuroblastoma cell line, SH-SY5Y, both dynamin 1 and cortactin localized on actin filaments and the bundles at growth cone filopodia as revealed by immunoelectron microscopy. In SH-SY5Y cell, acute inhibition of dynamin 1 by application of dynamin inhibitor led to growth cone collapse. Cortactin knockdown also reduced growth cone filopodia. Together, our results strongly suggest that dynamin 1 and cortactin ring complex mechanically stabilizes F-actin bundles in growth cone filopodia. Thus, the GTPase-dependent mechanochemical enzyme property of dynamin is commonly used both in endocytosis and regulation of F-actin bundles by a dynamin 1-cortactin complex.
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Amphiphysin I but not dynamin I nor synaptojanin mRNA expression increased after repeated methamphetamine administration in the rat cerebrum and cerebellum. J Neural Transm (Vienna) 2012; 120:1039-52. [PMID: 23224692 DOI: 10.1007/s00702-012-0931-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Accepted: 11/16/2012] [Indexed: 01/13/2023]
Abstract
Dopamine increases/decreases synaptic vesicle recycling and in schizophrenia the proteins/mRNA is decreased. We isolated cDNA clone, similar to amphiphysin 1 (vesicle protein) mRNA from the neocortex of rats injected repeatedly with methamphetamine using polymerase chain reaction (PCR) differential display. This clone is highly homologous to the 3' region of the human amphiphysin gene. PCR extension study using a primer specific for the rat amphiphysin 1 gene and a primer located within the clone revealed that it is the 3' UTR region of the rat amphiphysin 1 gene. Furthermore, in situ hybridization revealed that amphiphysin 1 mRNA is expressed in the cerebrum, medial thalamus, hippocampus and cerebellum. In the cerebellum, amphiphysin mRNA expression was confined to upper granule cell layer. Repeated methamphetamine administration increased amphiphysin I mRNA expression in both anterior part of the cerebrum, and the cerebellum. However, the repeated administration did not alter mRNA expression of the other vesicle proteins, synaptotagmin I, synapsin I, synaptojanin and dynamin I, we conclude that the repeated administration selectively increased amphiphysin 1 mRNA expression. Thus, amphiphysin 1 does not work as synaptic recycling, but it is suggested, as a part of pathogenesis of brain tissue injury (under Ca²⁺ and Mg²⁺ devoid environment) in repeated methamphetamine-injected states, the gene regulate actin-asssembly, learning, cell stress signaling and cell polarity.
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32
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Smith CM, Chircop M. Clathrin-mediated endocytic proteins are involved in regulating mitotic progression and completion. Traffic 2012; 13:1628-41. [PMID: 22901037 DOI: 10.1111/tra.12001] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2012] [Revised: 08/14/2012] [Accepted: 08/17/2012] [Indexed: 12/23/2022]
Abstract
A few proteins required for clathrin-mediated endocytosis (CME) are associated with successful completion of mitosis at distinct mitotic stages. Clathrin heavy chain (CHC) and epsin are required for chromosome segregation independent of their CME function and dynamin II (dynII) functions in the abscission stage of cytokinesis. In this study we screened for mitotic roles of eight CME proteins: CHC, α-adaptin, CALM, epsin, eps15, endophilin II (edpnII), syndapin II (sdpnII) and the GTPase dynII using a small interfering RNA targeting approach. All proteins, except for CALM, are associated with completion of the abscission stage of cytokinesis, suggesting that they function in this process in an endocytic-dependent manner. In support of this concept, overexpression of epsin(S357D), which blocks endocytosis, induced multinucleation. Moreover, six of them have a secondary role at earlier mitotic stages that is not dependent on their endocytic function: CHC, epsin and eps15 in chromosome segregation, and sdpnII, α-adaptin and CALM have a role in furrow ingression. Therefore, the role of endocytic proteins in mitosis is much broader than previously recognized.
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Affiliation(s)
- Charlotte M Smith
- Children's Medical Research Institute, The University of Sydney, 214 Hawkesbury Road, Westmead, NSW, 2145, Australia
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33
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External push and internal pull forces recruit curvature-sensing N-BAR domain proteins to the plasma membrane. Nat Cell Biol 2012; 14:874-81. [PMID: 22750946 PMCID: PMC3519285 DOI: 10.1038/ncb2533] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Accepted: 05/30/2012] [Indexed: 12/18/2022]
Abstract
Many of the more than 20 mammalian proteins with N-BAR domains1-2 control cell architecture3 and endocytosis4-5 by associating with curved sections of the plasma membrane (PM)6. It is not well understood whether N-BAR proteins are recruited directly by processes that mechanically curve the PM or indirectly by PM-associated adaptor proteins that recruit proteins with N-BAR domains that then induce membrane curvature. Here, we show that externally-induced inward deformation of the PM by cone-shaped nanostructures (Nanocones) and internally-induced inward deformation by contracting actin cables both trigger recruitment of isolated N-BAR domains to the curved PM. Markedly, live-cell imaging in adherent cells showed selective recruitment of full length N-BAR proteins and isolated N-BAR domains to PM sub-regions above Nanocone stripes. Electron microscopy confirmed that N-BAR domains are recruited to local membrane sites curved by Nanocones. We further showed that N-BAR domains are periodically recruited to curved PM sites during local lamellipodia retraction in the front of migrating cells. Recruitment required Myosin II-generated force applied to PM connected actin cables. Together, our study shows that N-BAR domains can be directly recruited to the PM by external push or internal pull forces that locally curve the PM.
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34
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Chen Y, Aardema J, Misra A, Corey SJ. BAR proteins in cancer and blood disorders. INTERNATIONAL JOURNAL OF BIOCHEMISTRY AND MOLECULAR BIOLOGY 2012; 3:198-208. [PMID: 22773959 PMCID: PMC3388730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 04/13/2012] [Accepted: 04/18/2012] [Indexed: 06/01/2023]
Abstract
Remodeling of the membrane and cytoskeleton is involved in a wide range of normal and pathologic cellular function. These are complex, highly-coordinated biochemical and biophysical processes involving dozens of proteins. Serving as a scaffold for a variety of proteins and possessing a domain that interacts with plasma membranes, the BAR family of proteins contribute to a range of cellular functions characterized by membrane and cytoskeletal remodeling. There are several subgroups of BAR proteins: BAR, N-BAR, I-BAR, and F-BAR. They differ in their ability to induce angles of membrane curvature and in their recruitment of effector proteins. Evidence is accumulating that BAR proteins contribute to cancer cell invasion, T cell trafficking, phagocytosis, and platelet production. In this review, we discuss the physiological function of BAR proteins and discuss how they contribute to blood and cancer disorders.
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Affiliation(s)
- Yolande Chen
- Departments of Pediatrics and Cell & Molecular Biology, Children’s Memorial Hospital, Robert H. Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of MedicineChicago, IL
| | - Jorie Aardema
- Departments of Pediatrics and Cell & Molecular Biology, Children’s Memorial Hospital, Robert H. Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of MedicineChicago, IL
| | - Ashish Misra
- Division of Cardiology, Department of Medicine, Yale University School of MedicineNew Haven, CT, USA
| | - Seth J Corey
- Departments of Pediatrics and Cell & Molecular Biology, Children’s Memorial Hospital, Robert H. Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of MedicineChicago, IL
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35
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Li DDU, Ameer-Beg S, Arlt J, Tyndall D, Walker R, Matthews DR, Visitkul V, Richardson J, Henderson RK. Time-domain fluorescence lifetime imaging techniques suitable for solid-state imaging sensor arrays. SENSORS 2012; 12:5650-69. [PMID: 22778606 PMCID: PMC3386705 DOI: 10.3390/s120505650] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/24/2012] [Revised: 04/18/2012] [Accepted: 04/26/2012] [Indexed: 11/27/2022]
Abstract
We have successfully demonstrated video-rate CMOS single-photon avalanche diode (SPAD)-based cameras for fluorescence lifetime imaging microscopy (FLIM) by applying innovative FLIM algorithms. We also review and compare several time-domain techniques and solid-state FLIM systems, and adapt the proposed algorithms for massive CMOS SPAD-based arrays and hardware implementations. The theoretical error equations are derived and their performances are demonstrated on the data obtained from 0.13 μm CMOS SPAD arrays and the multiple-decay data obtained from scanning PMT systems. In vivo two photon fluorescence lifetime imaging data of FITC-albumin labeled vasculature of a P22 rat carcinosarcoma (BD9 rat window chamber) are used to test how different algorithms perform on bi-decay data. The proposed techniques are capable of producing lifetime images with enough contrast.
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Affiliation(s)
- David Day-Uei Li
- Department of Engineering and Design, School of Engineering and Informatics, University of Sussex, Brighton BN1 9QT, UK
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +44-127-387-3513
| | - Simon Ameer-Beg
- Division of Cancer Research & Randall Division of Cell and Molecular Biophysics, Richard Dimbleby Department of Cancer Research, Guy's Campus, London SE1 1UL, UK; E-Mails: (S.A.B.); (V.V.)
| | - Jochen Arlt
- SUPA, COSMIC, School of Physics and Astronomy, The University of Edinburgh, The King's Buildings, Mayfield Road, Edinburgh EH9 3JZ, Scotland, UK; E-Mail:
| | - David Tyndall
- Institute for Integrated Micro and Nano Systems, The School of Engineering, The University of Edinburgh, The King's Buildings, Mayfield Road, Edinburgh EH9 3JL, Scotland, UK; E-Mails: (D.T.); (R.W.); (J.R.); (R.K.H.)
| | - Richard Walker
- Institute for Integrated Micro and Nano Systems, The School of Engineering, The University of Edinburgh, The King's Buildings, Mayfield Road, Edinburgh EH9 3JL, Scotland, UK; E-Mails: (D.T.); (R.W.); (J.R.); (R.K.H.)
| | - Daniel R. Matthews
- Queensland Brain Institute, University of Queensland, St. Lucia, QLD 4072, Australia; E-Mail:
| | - Viput Visitkul
- Division of Cancer Research & Randall Division of Cell and Molecular Biophysics, Richard Dimbleby Department of Cancer Research, Guy's Campus, London SE1 1UL, UK; E-Mails: (S.A.B.); (V.V.)
| | - Justin Richardson
- Institute for Integrated Micro and Nano Systems, The School of Engineering, The University of Edinburgh, The King's Buildings, Mayfield Road, Edinburgh EH9 3JL, Scotland, UK; E-Mails: (D.T.); (R.W.); (J.R.); (R.K.H.)
| | - Robert K. Henderson
- Institute for Integrated Micro and Nano Systems, The School of Engineering, The University of Edinburgh, The King's Buildings, Mayfield Road, Edinburgh EH9 3JL, Scotland, UK; E-Mails: (D.T.); (R.W.); (J.R.); (R.K.H.)
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Upadhyay RD, Kumar AV, Ganeshan M, Balasinor NH. Tubulobulbar complex: cytoskeletal remodeling to release spermatozoa. Reprod Biol Endocrinol 2012; 10:27. [PMID: 22510523 PMCID: PMC3442992 DOI: 10.1186/1477-7827-10-27] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Accepted: 03/30/2012] [Indexed: 11/15/2022] Open
Abstract
Tubulobulbar complexes (TBCs) are actin-based structures that help establish close contact between Sertoli-Sertoli cells or Sertoli-mature germ cells (spermatids) in the seminiferous tubules of the testes. They are actin-rich push-through devices that eliminate excess spermatid cytoplasm and prepare mature spermatids for release into the tubular lumen. Just prior to spermiation, the elongated spermatid interacts with the Sertoli cell via an extensive structure comprising various adhesion molecules called the apical ectoplasmic specialization which is partially replaced by the apical TBC, on the concave surface of the spermatid head. The sperm release process involves extensive restructuring, namely the disassembly and reassembly of junctions at the Sertoli-spermatid interface in the seminiferous epithelium. Based on the presence of different classes of molecules in the TBCs or the defects observed in the absence of TBCs, the main functions attributed to TBCs are elimination of excess spermatid cytoplasm, endocytosis and recycling of junctional molecules, shaping of the spermatid acrosome, and forming transient anchoring devices for mature spermatids before they are released. This review summarizes the recent findings that focus on the role of TBCs in cell cytoskeleton restructuring during sperm release in the testes and the molecular mechanism involved.
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Affiliation(s)
- Rahul D Upadhyay
- Department of Neuroendocrinology, National Institute for Research in Reproductive Health, J.M.Street, Parel, Mumbai, 400012, India
| | - Anita V Kumar
- Department of Neuroendocrinology, National Institute for Research in Reproductive Health, J.M.Street, Parel, Mumbai, 400012, India
| | - Malti Ganeshan
- Department of Neuroendocrinology, National Institute for Research in Reproductive Health, J.M.Street, Parel, Mumbai, 400012, India
| | - Nafisa H Balasinor
- Department of Neuroendocrinology, National Institute for Research in Reproductive Health, J.M.Street, Parel, Mumbai, 400012, India
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Padilla-Parra S, Tramier M. FRET microscopy in the living cell: Different approaches, strengths and weaknesses. Bioessays 2012; 34:369-76. [DOI: 10.1002/bies.201100086] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Revised: 09/15/2011] [Accepted: 09/28/2011] [Indexed: 02/02/2023]
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The BAR Domain Superfamily Proteins from Subcellular Structures to Human Diseases. MEMBRANES 2012; 2:91-117. [PMID: 24957964 PMCID: PMC4021885 DOI: 10.3390/membranes2010091] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2012] [Revised: 02/07/2012] [Accepted: 02/15/2012] [Indexed: 12/11/2022]
Abstract
Eukaryotic cells have complicated membrane systems. The outermost plasma membrane contains various substructures, such as invaginations and protrusions, which are involved in endocytosis and cell migration. Moreover, the intracellular membrane compartments, such as autophagosomes and endosomes, are essential for cellular viability. The Bin-Amphiphysin-Rvs167 (BAR) domain superfamily proteins are important players in membrane remodeling through their structurally determined membrane binding surfaces. A variety of BAR domain superfamily proteins exist, and each family member appears to be involved in the formation of certain subcellular structures or intracellular membrane compartments. Most of the BAR domain superfamily proteins contain SH3 domains, which bind to the membrane scission molecule, dynamin, as well as the actin regulatory WASP/WAVE proteins and several signal transduction molecules, providing possible links between the membrane and the cytoskeleton or other machineries. In this review, we summarize the current information about each BAR superfamily protein with an SH3 domain(s). The involvement of BAR domain superfamily proteins in various diseases is also discussed.
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Suetsugu S, Gautreau A. Synergistic BAR-NPF interactions in actin-driven membrane remodeling. Trends Cell Biol 2012; 22:141-50. [PMID: 22306177 DOI: 10.1016/j.tcb.2012.01.001] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2011] [Revised: 12/29/2011] [Accepted: 01/03/2012] [Indexed: 10/14/2022]
Abstract
Cell and organelle shape can profoundly influence proper cellular function. In recent years, two machineries have emerged as major regulators of membrane shape: Bin-Amphiphysin-Rvs161/167 (BAR) domain-containing proteins, which induce membrane invaginations or protrusions, and nucleation promoting factors (NPFs), which activate the Arp2/3 complex and are thus responsible for the generation of branched actin networks that push on membranes. Several BAR-NPF interactions have been shown to induce various types of protrusions, such as lamellipodia or filopodia, or invaginations, including trafficking organelles such as caveolae, endosomes and clathrin-coated pits (CCPs). This review focuses on how collaboration between these two interacting machineries, which emerges as a unified mechanism of membrane remodeling, accounts for such a variety of membrane shapes.
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Affiliation(s)
- Shiro Suetsugu
- Laboratory of Membrane and Cytoskeleton Dynamics, Institute of Molecular and Cellular Biosciences, University of Tokyo, 1-1-1, Yayoi, Tokyo, 113-0032, Japan.
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Abstract
Synaptic transmission is amongst the most sophisticated and tightly controlled biological phenomena in higher eukaryotes. In the past few decades, tremendous progress has been made in our understanding of the molecular mechanisms underlying multiple facets of neurotransmission, both pre- and postsynaptically. Brought under the spotlight by pioneer studies in the areas of secretion and signal transduction, phosphoinositides and their metabolizing enzymes have been increasingly recognized as key protagonists in fundamental aspects of neurotransmission. Not surprisingly, dysregulation of phosphoinositide metabolism has also been implicated in synaptic malfunction associated with a variety of brain disorders. In the present chapter, we summarize current knowledge on the role of phosphoinositides at the neuronal synapse and highlight some of the outstanding questions in this research field.
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Affiliation(s)
- Samuel G Frere
- Department of Pathology and Cell Biology, Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, 630 West 168th Street, P&S 12-420C, 10032, New York, USA
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Park J, Sung JY, Park J, Song WJ, Chang S, Chung KC. Dyrk1A negatively regulates the actin cytoskeleton through threonine phosphorylation of N-WASP. J Cell Sci 2012; 125:67-80. [PMID: 22250195 DOI: 10.1242/jcs.086124] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Neural Wiskott-Aldrich syndrome protein (N-WASP) is involved in tight regulation of actin polymerization and dynamics. N-WASP activity is regulated by intramolecular interaction, binding to small GTPases and tyrosine phosphorylation. Here, we report on a novel regulatory mechanism; we demonstrate that N-WASP interacts with dual-specificity tyrosine-phosphorylation-regulated kinase 1A (Dyrk1A). In vitro kinase assays indicate that Dyrk1A directly phosphorylates the GTPase-binding domain (GBD) of N-WASP at three sites (Thr196, Thr202 and Thr259). Phosphorylation of the GBD by Dyrk1A promotes the intramolecular interaction of the GBD and verprolin, cofilin and acidic (VCA) domains of N-WASP, and subsequently inhibits Arp2/3-complex-mediated actin polymerization. Overexpression of either Dyrk1A or a phospho-mimetic N-WASP mutant inhibits filopodia formation in COS-7 cells. By contrast, the knockdown of Dyrk1A expression or overexpression of a phospho-deficient N-WASP mutant promotes filopodia formation. Furthermore, the overexpression of a phospho-mimetic N-WASP mutant significantly inhibits dendritic spine formation in primary hippocampal neurons. These findings suggest that Dyrk1A negatively regulates actin filament assembly by phosphorylating N-WASP, which ultimately promotes the intramolecular interaction of its GBD and VCA domains. These results provide insight on the mechanisms contributing to diverse actin-based cellular processes such as cell migration, endocytosis and neuronal differentiation.
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Affiliation(s)
- Joongkyu Park
- Department of Systems Biology, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea
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Abstract
Clathrin-mediated endocytosis (CME) is the major pathway for internalization of membrane proteins from the cell surface. Half a century of studies have uncovered tremendous insights into how a clathrin-coated vesicle is formed. More recently, the advent of live-cell imaging has provided a dynamic view of this process. As CME is highly conserved from yeast to humans, budding yeast provides an evolutionary template for this process and has been a valuable system for dissecting the underlying molecular mechanisms. In this review we trace the formation of a clathrin-coated vesicle from initiation to uncoating, focusing on key findings from the yeast system.
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Rao Y, Haucke V. Membrane shaping by the Bin/amphiphysin/Rvs (BAR) domain protein superfamily. Cell Mol Life Sci 2011; 68:3983-93. [PMID: 21769645 PMCID: PMC11114942 DOI: 10.1007/s00018-011-0768-5] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Revised: 06/27/2011] [Accepted: 06/30/2011] [Indexed: 01/27/2023]
Abstract
BAR domain superfamily proteins have emerged as central regulators of dynamic membrane remodeling, thereby playing important roles in a wide variety of cellular processes, such as organelle biogenesis, cell division, cell migration, secretion, and endocytosis. Here, we review the mechanistic and structural basis for the membrane curvature-sensing and deforming properties of BAR domain superfamily proteins. Moreover, we summarize the present state of knowledge with respect to their regulation by autoinhibitory mechanisms or posttranslational modifications, and their interactions with other proteins, in particular with GTPases, and with membrane lipids. We postulate that BAR superfamily proteins act as membrane-deforming scaffolds that spatiotemporally orchestrate membrane remodeling.
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Affiliation(s)
- Yijian Rao
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Takustraße 6, 14195 Berlin, Germany
- Present Address: Max Planck Institute for Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - Volker Haucke
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Takustraße 6, 14195 Berlin, Germany
- NeuroCure Cluster of Excellence, Charité Berlin, Charitéplatz 1, 10117 Berlin, Germany
- Leibniz-Institut für Molekulare Pharmakologie (FMP), Robert-Rössle-Straße 10, 13125 Berlin, Germany
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44
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Function and regulation of Saccharomyces cerevisiae myosins-I in endocytic budding. Biochem Soc Trans 2011; 39:1185-90. [DOI: 10.1042/bst0391185] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Myosins-I are widely expressed actin-dependent motors which bear a phospholipid-binding domain. In addition, some members of the family can trigger Arp2/3 complex (actin-related protein 2/3 complex)-dependent actin polymerization. In the early 1990s, the development of powerful genetic tools in protozoa and mammals and discovery of these motors in yeast allowed the demonstration of their roles in membrane traffic along the endocytic and secretory pathways, in vacuole contraction, in cell motility and in mechanosensing. The powerful yeast genetics has contributed towards dissecting in detail the function and regulation of Saccharomyces cerevisiae myosins-I Myo3 and Myo5 in endocytic budding from the plasma membrane. In the present review, we summarize the evidence, dissecting their exact role in membrane budding and the molecular mechanisms controlling their recruitment and biochemical activities at the endocytic sites.
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Qualmann B, Koch D, Kessels MM. Let's go bananas: revisiting the endocytic BAR code. EMBO J 2011; 30:3501-15. [PMID: 21878992 DOI: 10.1038/emboj.2011.266] [Citation(s) in RCA: 182] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Accepted: 07/15/2011] [Indexed: 12/27/2022] Open
Abstract
Against the odds of membrane resistance, members of the BIN/Amphiphysin/Rvs (BAR) domain superfamily shape membranes and their activity is indispensable for a plethora of life functions. While crystal structures of different BAR dimers advanced our understanding of membrane shaping by scaffolding and hydrophobic insertion mechanisms considerably, especially life-imaging techniques and loss-of-function studies of clathrin-mediated endocytosis with its gradually increasing curvature show that the initial idea that solely BAR domain curvatures determine their functions is oversimplified. Diagonal placing, lateral lipid-binding modes, additional lipid-binding modules, tilde shapes and formation of macromolecular lattices with different modes of organisation and arrangement increase versatility. A picture emerges, in which BAR domain proteins create macromolecular platforms, that recruit and connect different binding partners and ensure the connection and coordination of the different events during the endocytic process, such as membrane invagination, coat formation, actin nucleation, vesicle size control, fission, detachment and uncoating, in time and space, and may thereby offer mechanistic explanations for how coordination, directionality and effectiveness of a complex process with several steps and key players can be achieved.
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Affiliation(s)
- Britta Qualmann
- Institute for Biochemistry I, University Hospital Jena-Friedrich Schiller University Jena, Germany.
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Mahankali M, Peng HJ, Cox D, Gomez-Cambronero J. The mechanism of cell membrane ruffling relies on a phospholipase D2 (PLD2), Grb2 and Rac2 association. Cell Signal 2011; 23:1291-8. [PMID: 21419846 PMCID: PMC3095729 DOI: 10.1016/j.cellsig.2011.03.010] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2011] [Revised: 03/09/2011] [Accepted: 03/10/2011] [Indexed: 01/20/2023]
Abstract
Membrane ruffling is the formation of actin rich membrane protrusions, essential for cell motility. The exact mechanism of ruffling is not fully known. Using YFP and CFP fluorescent chimeras, we show for the first time a co-localization of Phospholipase D2 (PLD2) and Growth factor Receptor Bound protein-2 (Grb2) with actin-rich membrane protrusions of macrophages. Grb2 cooperates with PLD2 in enhancing membrane ruffling, whether in resting cells or in cells stimulated with the growth factor M-CSF, although in the latter an increase in dorsal ruffles was observed, consistent with receptor-ligand internalization. Cells transfected with PLD2 mutated in the PH domain (Y169F) or with Grb2 mutated in the SH2 site (R86K) negate this effect, indicating an association PLD2(Y169)-SH2-Grb2 that was confirmed by immunoprecipitation and Western blotting. The association results in enhanced PLD activity, but the lipase activity can only partially explain the formation of membrane ruffles in vivo. A third component involves the Rho-GTPase Rac2 and it is only when Rac2 is overexpressed along with PLD2 and Rac2 that a full biological effect, including actin polymerization in vivo, is obtained. The mechanism involved is, then, as follows: PLD enzymatic action, after having been increased due to the binding to Grb2-SH2 via Y169, cooperates with Rac2, and the three molecules stimulate actin polymerization and consequently, membrane ruffle formation. Since membrane ruffling precedes cell migration, the results herein provide a novel mechanism for control of membrane dynamics, crucial for the physiology of leukocytes.
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Affiliation(s)
- Madhu Mahankali
- Dept. Biochemistry & Molecular Biology, Wright State University School Medicine, Dayton, OH 45435
| | - Hong-Juan Peng
- Dept. Biochemistry & Molecular Biology, Wright State University School Medicine, Dayton, OH 45435
| | - Dianne Cox
- Albert Einstein School of Medicine Yeshiva University, NY
| | - Julian Gomez-Cambronero
- Dept. Biochemistry & Molecular Biology, Wright State University School Medicine, Dayton, OH 45435
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Liu F, He K, Yang X, Xu N, Liang Z, Xu M, Zhao X, Han Q, Zhang Y. α1A-adrenergic receptor induces activation of extracellular signal-regulated kinase 1/2 through endocytic pathway. PLoS One 2011; 6:e21520. [PMID: 21738688 PMCID: PMC3125289 DOI: 10.1371/journal.pone.0021520] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2011] [Accepted: 05/30/2011] [Indexed: 11/22/2022] Open
Abstract
G protein-coupled receptors (GPCRs) activate mitogen-activated protein kinases through a number of distinct pathways in cells. Increasing evidence has suggested that endosomal signaling has an important role in receptor signal transduction. Here we investigated the involvement of endocytosis in α1A-adrenergic receptor (α1A-AR)-induced activation of extracellular signal-regulated kinase 1/2 (ERK1/2). Agonist-mediated endocytic traffic of α1A-AR was assessed by real-time imaging of living, stably transfected human embryonic kidney 293A cells (HEK-293A). α1A-AR was internalized dynamically in cells with agonist stimulation, and actin filaments regulated the initial trafficking of α1A-AR. α1A-AR-induced activation of ERK1/2 but not p38 MAPK was sensitive to disruption of endocytosis, as demonstrated by 4°C chilling, dynamin mutation and treatment with cytochalasin D (actin depolymerizing agent). Activation of protein kinase C (PKC) and C-Raf by α1A-AR was not affected by 4°C chilling or cytochalasin D treatment. U73122 (a phospholipase C [PLC] inhibitor) and Ro 31–8220 (a PKC inhibitor) inhibited α1B-AR- but not α1A-AR-induced ERK1/2 activation. These data suggest that the endocytic pathway is involved in α1A-AR-induced ERK1/2 activation, which is independent of Gq/PLC/PKC signaling.
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Affiliation(s)
- Fei Liu
- Institute of Vascular Medicine, Peking University Third Hospital, and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing, China
| | - Kangmin He
- Institute of Vascular Medicine, Peking University Third Hospital, and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing, China
| | - Xinxing Yang
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Biodynamic Optical Imaging Center, Peking University, Beijing, China
| | - Ning Xu
- Institute of Vascular Medicine, Peking University Third Hospital, and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing, China
| | - Zhangyi Liang
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Biodynamic Optical Imaging Center, Peking University, Beijing, China
| | - Ming Xu
- Institute of Vascular Medicine, Peking University Third Hospital, and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing, China
| | - Xinsheng Zhao
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Department of Chemical Biology, College of Chemistry and Molecular Engineering, Biodynamic Optical Imaging Center, Peking University, Beijing, China
| | - Qide Han
- Institute of Vascular Medicine, Peking University Third Hospital, and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing, China
| | - Youyi Zhang
- Institute of Vascular Medicine, Peking University Third Hospital, and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Beijing, China
- * E-mail:
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Non fitting based FRET-FLIM analysis approaches applied to quantify protein-protein interactions in live cells. Biophys Rev 2011; 3:63-70. [PMID: 28510004 DOI: 10.1007/s12551-011-0047-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2011] [Accepted: 04/26/2011] [Indexed: 01/14/2023] Open
Abstract
New imaging methodologies in quantitative fluorescence microscopy and nanoscopy have been developed in the last few years and are beginning to be extensively applied to biological problems, such as the localization and quantification of protein interactions. Fluorescence resonance energy transfer (FRET) detected by fluorescence lifetime imaging microscopy (FLIM) is currently employed not only in biophysics or chemistry but also in bio-medicine, thanks to new advancements in technology and also new developments in data treatment. FRET-FLIM can be a very useful tool to ascertain protein interactions occurring in single living cells. In this review, we stress the importance of increasing the acquisition speed when working in vivo employing Time-Domain FLIM. The development of the new mathematical-based non-fitting methods allows the determining of the fraction of interacting donor without the requirement of high count statistics, and thus allows the performing of high speed acquisitions in FRET-FLIM to still be quantitative.
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Popescu CI, Callens N, Trinel D, Roingeard P, Moradpour D, Descamps V, Duverlie G, Penin F, Héliot L, Rouillé Y, Dubuisson J. NS2 protein of hepatitis C virus interacts with structural and non-structural proteins towards virus assembly. PLoS Pathog 2011; 7:e1001278. [PMID: 21347350 PMCID: PMC3037360 DOI: 10.1371/journal.ppat.1001278] [Citation(s) in RCA: 125] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2010] [Accepted: 01/07/2011] [Indexed: 02/07/2023] Open
Abstract
Growing experimental evidence indicates that, in addition to the physical virion components, the non-structural proteins of hepatitis C virus (HCV) are intimately involved in orchestrating morphogenesis. Since it is dispensable for HCV RNA replication, the non-structural viral protein NS2 is suggested to play a central role in HCV particle assembly. However, despite genetic evidences, we have almost no understanding about NS2 protein-protein interactions and their role in the production of infectious particles. Here, we used co-immunoprecipitation and/or fluorescence resonance energy transfer with fluorescence lifetime imaging microscopy analyses to study the interactions between NS2 and the viroporin p7 and the HCV glycoprotein E2. In addition, we used alanine scanning insertion mutagenesis as well as other mutations in the context of an infectious virus to investigate the functional role of NS2 in HCV assembly. Finally, the subcellular localization of NS2 and several mutants was analyzed by confocal microscopy. Our data demonstrate molecular interactions between NS2 and p7 and E2. Furthermore, we show that, in the context of an infectious virus, NS2 accumulates over time in endoplasmic reticulum-derived dotted structures and colocalizes with both the envelope glycoproteins and components of the replication complex in close proximity to the HCV core protein and lipid droplets, a location that has been shown to be essential for virus assembly. We show that NS2 transmembrane region is crucial for both E2 interaction and subcellular localization. Moreover, specific mutations in core, envelope proteins, p7 and NS5A reported to abolish viral assembly changed the subcellular localization of NS2 protein. Together, these observations indicate that NS2 protein attracts the envelope proteins at the assembly site and it crosstalks with non-structural proteins for virus assembly. Hepatitis C virus (HCV) causes major health problems worldwide. Understanding the major steps of the life cycle of this virus is essential to developing new and more efficient antiviral molecules. Virus assembly is the least understood step of the HCV life cycle. Growing experimental evidence indicates that, in addition to the physical virion components, the HCV non-structural proteins are intimately involved in orchestrating morphogenesis. Since it is dispensable for HCV RNA replication, the non-structural viral protein NS2 is suggested to play a central role in HCV particle assembly. Molecular interactions between NS2 and other HCV proteins were demonstrated. Furthermore, NS2 was shown to accumulate over time in endoplasmic reticulum-derived structures and to colocalize with the viral envelope glycoproteins and viral components of the replication complex in close proximity to the HCV core protein and lipid droplets. Importantly, specific mutations within NS2 that affected HCV infectivity could also alter the subcellular localization of NS2 protein and its interactions, suggesting that this subcellular localization and its interactions are essential for HCV particle assembly. Altogether, these observations indicate that NS2 protein plays an important role in connecting different viral components that are essential for virus assembly.
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Affiliation(s)
- Costin-Ioan Popescu
- Inserm U1019, CNRS UMR8204, Center for Infection & Immunity of Lille (CIIL), Institut Pasteur de Lille, Université Lille Nord de France, Lille, France
- Institute of Biochemistry of the Romanian Academy, Bucharest, Romania
| | - Nathalie Callens
- Inserm U1019, CNRS UMR8204, Center for Infection & Immunity of Lille (CIIL), Institut Pasteur de Lille, Université Lille Nord de France, Lille, France
| | - Dave Trinel
- Institute of Interdisciplinary Research, University Lille 1, Villeneuve d'Ascq, France
| | - Philippe Roingeard
- INSERM U966, Université François Rabelais and CHRU de Tours, Tours, France
| | - Darius Moradpour
- Division of Gastroenterology and Hepatology, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
| | - Véronique Descamps
- Laboratoire de Virologie, Centre Hospitalier Universitaire d'Amiens, Amiens, France
| | - Gilles Duverlie
- Laboratoire de Virologie, Centre Hospitalier Universitaire d'Amiens, Amiens, France
| | - François Penin
- Institut de Biologie et Chimie des Protéines, UMR-5086-CNRS, Université de Lyon, Lyon, France
| | - Laurent Héliot
- Institute of Interdisciplinary Research, University Lille 1, Villeneuve d'Ascq, France
| | - Yves Rouillé
- Inserm U1019, CNRS UMR8204, Center for Infection & Immunity of Lille (CIIL), Institut Pasteur de Lille, Université Lille Nord de France, Lille, France
| | - Jean Dubuisson
- Inserm U1019, CNRS UMR8204, Center for Infection & Immunity of Lille (CIIL), Institut Pasteur de Lille, Université Lille Nord de France, Lille, France
- * E-mail:
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O'Donnell L, Nicholls PK, O'Bryan MK, McLachlan RI, Stanton PG. Spermiation: The process of sperm release. SPERMATOGENESIS 2011; 1:14-35. [PMID: 21866274 DOI: 10.4161/spmg.1.1.14525] [Citation(s) in RCA: 244] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Revised: 12/16/2010] [Accepted: 12/17/2010] [Indexed: 02/06/2023]
Abstract
Spermiation is the process by which mature spermatids are released from Sertoli cells into the seminiferous tubule lumen prior to their passage to the epididymis. It takes place over several days at the apical edge of the seminiferous epithelium, and involves several discrete steps including remodelling of the spermatid head and cytoplasm, removal of specialized adhesion structures and the final disengagement of the spermatid from the Sertoli cell. Spermiation is accomplished by the co-ordinated interactions of various structures, cellular processes and adhesion complexes which make up the "spermiation machinery". This review addresses the morphological, ultrastructural and functional aspects of mammalian spermiation. The molecular composition of the spermiation machinery, its dynamic changes and regulatory factors are examined. The causes of spermiation failure and their impact on sperm morphology and function are assessed in an effort to understand how this process may contribute to sperm count suppression during contraception and to phenotypes of male infertility.
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Affiliation(s)
- Liza O'Donnell
- Prince Henry's Institute of Medical Research; Clayton, VIC Australia
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