1
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Hämälistö S, Del Valle Batalla F, Yuseff MI, Mattila PK. Endolysosomal vesicles at the center of B cell activation. J Cell Biol 2024; 223:e202307047. [PMID: 38305771 PMCID: PMC10837082 DOI: 10.1083/jcb.202307047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 12/22/2023] [Accepted: 01/17/2024] [Indexed: 02/03/2024] Open
Abstract
The endolysosomal system specializes in degrading cellular components and is crucial to maintaining homeostasis and adapting rapidly to metabolic and environmental cues. Cells of the immune system exploit this network to process antigens or promote cell death by secreting lysosome-related vesicles. In B lymphocytes, lysosomes are harnessed to facilitate the extraction of antigens and to promote their processing into peptides for presentation to T cells, critical steps to mount protective high-affinity antibody responses. Intriguingly, lysosomal vesicles are now considered important signaling units within cells and also display secretory functions by releasing their content to the extracellular space. In this review, we focus on how B cells use pathways involved in the intracellular trafficking, secretion, and function of endolysosomes to promote adaptive immune responses. A basic understanding of such mechanisms poses an interesting frontier for the development of therapeutic strategies in the context of cancer and autoimmune diseases.
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Affiliation(s)
- Saara Hämälistö
- Institute of Biomedicine, and MediCity Research Laboratories, University of Turku, Turku, Finland
- Turku Bioscience, University of Turku and Åbo Akademi University, Turku, Finland
- InFLAMES Research Flagship, University of Turku, Turku, Finland
- Cancer Research Unit and FICAN West Cancer Centre Laboratory, Turku, Finland
| | - Felipe Del Valle Batalla
- Laboratory of Immune Cell Biology, Department of Cellular and Molecular Biology, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - María Isabel Yuseff
- Laboratory of Immune Cell Biology, Department of Cellular and Molecular Biology, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Pieta K. Mattila
- Institute of Biomedicine, and MediCity Research Laboratories, University of Turku, Turku, Finland
- Turku Bioscience, University of Turku and Åbo Akademi University, Turku, Finland
- InFLAMES Research Flagship, University of Turku, Turku, Finland
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2
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Bjornson KJ, Vanderplow AM, Yang Y, Anderson DR, Kermath BA, Cahill ME. Stress-mediated dysregulation of the Rap1 small GTPase impairs hippocampal structure and function. iScience 2023; 26:107566. [PMID: 37664580 PMCID: PMC10470260 DOI: 10.1016/j.isci.2023.107566] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 05/15/2023] [Accepted: 08/02/2023] [Indexed: 09/05/2023] Open
Abstract
The effects of repeated stress on cognitive impairment are thought to be mediated, at least in part, by reductions in the stability of dendritic spines in brain regions critical for proper learning and memory, including the hippocampus. Small GTPases are particularly potent regulators of dendritic spine formation, stability, and morphology in hippocampal neurons. Through the use of small GTPase protein profiling in mice, we identify increased levels of synaptic Rap1 in the hippocampal CA3 region in response to escalating, intermittent stress. We then demonstrate that increased Rap1 in the CA3 is sufficient in and of itself to produce stress-relevant dendritic spine and cognitive phenotypes. Further, using super-resolution imaging, we investigate how the pattern of Rap1 trafficking to synapses likely underlies its effects on the stability of select dendritic spine subtypes. These findings illuminate the involvement of aberrant Rap1 regulation in the hippocampus in contributing to the psychobiological effects of stress.
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Affiliation(s)
- Kathryn J. Bjornson
- Department of Comparative Biosciences, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Amanda M. Vanderplow
- Department of Comparative Biosciences, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Yezi Yang
- Department of Comparative Biosciences, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Danielle R. Anderson
- Department of Comparative Biosciences, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Bailey A. Kermath
- Department of Comparative Biosciences, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Michael E. Cahill
- Department of Comparative Biosciences, University of Wisconsin-Madison, Madison, WI 53706, USA
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3
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Wong DCP, Ding JL. The mechanobiology of NK cells- 'Forcing NK to Sense' target cells. Biochim Biophys Acta Rev Cancer 2023; 1878:188860. [PMID: 36791921 DOI: 10.1016/j.bbcan.2023.188860] [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: 11/23/2022] [Revised: 01/06/2023] [Accepted: 01/16/2023] [Indexed: 02/16/2023]
Abstract
Natural killer (NK) cells are innate immune lymphocytes that recognize and kill cancer and infected cells, which makes them unique 'off-the-shelf' candidates for a new generation of immunotherapies. Biomechanical forces in homeostasis and pathophysiology accrue additional immune regulation for NK immune responses. Indeed, cellular and tissue biomechanics impact NK receptor clustering, cytoskeleton remodeling, NK transmigration through endothelial cells, nuclear mechanics, and even NK-dendritic cell interaction, offering a plethora of unexplored yet important dynamic regulation for NK immunotherapy. Such events are made more complex by the heterogeneity of human NK cells. A significant question remains on whether and how biochemical and biomechanical cues collaborate for NK cell mechanotransduction, a process whereby mechanical force is sensed, transduced, and translated to downstream mechanical and biochemical signalling. Herein, we review recent advances in understanding how NK cells perceive and mechanotransduce biophysical cues. We focus on how the cellular cytoskeleton crosstalk regulates NK cell function while bearing in mind the heterogeneity of NK cells, the direct and indirect mechanical cues for NK anti-tumor activity, and finally, engineering advances that are of translational relevance to NK cell biology at the systems level.
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Affiliation(s)
- Darren Chen Pei Wong
- Department of Biological Sciences, National University of Singapore, 117543, Singapore.
| | - Jeak Ling Ding
- Department of Biological Sciences, National University of Singapore, 117543, Singapore; Integrative Sciences and Engineering Programme, National University of Singapore, 119077, Singapore.
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4
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Pinon L, Ruyssen N, Pineau J, Mesdjian O, Cuvelier D, Chipont A, Allena R, Guerin CL, Asnacios S, Asnacios A, Pierobon P, Fattaccioli J. Phenotyping polarization dynamics of immune cells using a lipid droplet-cell pairing microfluidic platform. CELL REPORTS METHODS 2022; 2:100335. [PMID: 36452873 PMCID: PMC9701611 DOI: 10.1016/j.crmeth.2022.100335] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Revised: 09/20/2022] [Accepted: 10/19/2022] [Indexed: 05/12/2023]
Abstract
The immune synapse is the tight contact zone between a lymphocyte and a cell presenting its cognate antigen. This structure serves as a signaling platform and entails a polarization of intracellular components necessary to the immunological function of the cell. While the surface properties of the presenting cell are known to control the formation of the synapse, their impact on polarization has not yet been studied. Using functional lipid droplets as tunable artificial presenting cells combined with a microfluidic pairing device, we simultaneously observe synchronized synapses and dynamically quantify polarization patterns of individual B cells. By assessing how ligand concentration, surface fluidity, and substrate rigidity impact lysosome polarization, we show that its onset and kinetics depend on the local antigen concentration at the synapse and on substrate rigidity. Our experimental system enables a fine phenotyping of monoclonal cell populations based on their synaptic readout.
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Affiliation(s)
- Léa Pinon
- École Normale Supérieure, UMR 8640, Laboratoire PASTEUR, Département de Chimie, PSL Research University, Sorbonne Université, CNRS, 75005 Paris, France
- Institut Curie, U932, Immunology and Cancer, INSERM, 75005 Paris, France
- Institut Pierre-Gilles de Gennes pour la Microfluidique, 75005 Paris, France
| | - Nicolas Ruyssen
- Arts et Métiers Institute of Technology, Université Paris 13, Sorbonne Paris Cité, IBHGC, HESAM Université, 75013 Paris, France
| | - Judith Pineau
- Institut Curie, U932, Immunology and Cancer, INSERM, 75005 Paris, France
| | - Olivier Mesdjian
- École Normale Supérieure, UMR 8640, Laboratoire PASTEUR, Département de Chimie, PSL Research University, Sorbonne Université, CNRS, 75005 Paris, France
- Institut Pierre-Gilles de Gennes pour la Microfluidique, 75005 Paris, France
| | - Damien Cuvelier
- Institut Pierre-Gilles de Gennes pour la Microfluidique, 75005 Paris, France
- Institut Curie, UMR 144, PSL Research University, CNRS, Paris, France
- Sorbonne Université, Faculté des Sciences et Ingénierie, UFR 926 Chemistry, 75005 Paris, France
| | - Anna Chipont
- Institut Curie, Cytometry Platform, 75005 Paris, France
| | - Rachele Allena
- Arts et Métiers Institute of Technology, Université Paris 13, Sorbonne Paris Cité, IBHGC, HESAM Université, 75013 Paris, France
- LJAD, UMR 7351, Université Côte d’Azur, 06100 Nice, France
| | - Coralie L. Guerin
- Institut Curie, Cytometry Platform, 75005 Paris, France
- Université Paris Cité, INSERM, Innovative Therapies in Haemostasis, 75006 Paris, France
| | - Sophie Asnacios
- Université de Paris, CNRS, Laboratoire Matière et Systèmes Complexes, UMR 7057, 75013 Paris, France
- Sorbonne Université, Faculté des Sciences et Ingénierie, UFR 925 Physics, 75005 Paris, France
| | - Atef Asnacios
- Université de Paris, CNRS, Laboratoire Matière et Systèmes Complexes, UMR 7057, 75013 Paris, France
| | - Paolo Pierobon
- Institut Curie, U932, Immunology and Cancer, INSERM, 75005 Paris, France
| | - Jacques Fattaccioli
- École Normale Supérieure, UMR 8640, Laboratoire PASTEUR, Département de Chimie, PSL Research University, Sorbonne Université, CNRS, 75005 Paris, France
- Institut Pierre-Gilles de Gennes pour la Microfluidique, 75005 Paris, France
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5
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Wang JC, Yim YI, Wu X, Jaumouille V, Cameron A, Waterman CM, Kehrl JH, Hammer JA. A B-cell actomyosin arc network couples integrin co-stimulation to mechanical force-dependent immune synapse formation. eLife 2022; 11:e72805. [PMID: 35404237 PMCID: PMC9142150 DOI: 10.7554/elife.72805] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 04/10/2022] [Indexed: 11/13/2022] Open
Abstract
B-cell activation and immune synapse (IS) formation with membrane-bound antigens are actin-dependent processes that scale positively with the strength of antigen-induced signals. Importantly, ligating the B-cell integrin, LFA-1, with ICAM-1 promotes IS formation when antigen is limiting. Whether the actin cytoskeleton plays a specific role in integrin-dependent IS formation is unknown. Here, we show using super-resolution imaging of mouse primary B cells that LFA-1:ICAM-1 interactions promote the formation of an actomyosin network that dominates the B-cell IS. This network is created by the formin mDia1, organized into concentric, contractile arcs by myosin 2A, and flows inward at the same rate as B-cell receptor (BCR):antigen clusters. Consistently, individual BCR microclusters are swept inward by individual actomyosin arcs. Under conditions where integrin is required for synapse formation, inhibiting myosin impairs synapse formation, as evidenced by reduced antigen centralization, diminished BCR signaling, and defective signaling protein distribution at the synapse. Together, these results argue that a contractile actomyosin arc network plays a key role in the mechanism by which LFA-1 co-stimulation promotes B-cell activation and IS formation.
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Affiliation(s)
- Jia C Wang
- Cell and Developmental Biology Center, National Heart, Lung and Blood Institute, National Institutes of HealthBethesdaUnited States
| | - Yang-In Yim
- Cell and Developmental Biology Center, National Heart, Lung and Blood Institute, National Institutes of HealthBethesdaUnited States
| | - Xufeng Wu
- Light Microscopy Core, National Heart, Lung and Blood Institute, National Institutes of HealthBethesdaUnited States
| | - Valentin Jaumouille
- Cell and Developmental Biology Center, National Heart, Lung and Blood Institute, National Institutes of HealthBethesdaUnited States
| | - Andrew Cameron
- Cell and Developmental Biology Center, National Heart, Lung and Blood Institute, National Institutes of HealthBethesdaUnited States
| | - Clare M Waterman
- Cell and Developmental Biology Center, National Heart, Lung and Blood Institute, National Institutes of HealthBethesdaUnited States
| | - John H Kehrl
- B Cell Molecular Immunology Section, National Institutes of Allergy and Infectious Diseases, National Institutes of HealthBethesdaUnited States
| | - John A Hammer
- Cell and Developmental Biology Center, National Heart, Lung and Blood Institute, National Institutes of HealthBethesdaUnited States
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6
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Sun J, Zhong X, Fu X, Miller H, Lee P, Yu B, Liu C. The Actin Regulators Involved in the Function and Related Diseases of Lymphocytes. Front Immunol 2022; 13:799309. [PMID: 35371070 PMCID: PMC8965893 DOI: 10.3389/fimmu.2022.799309] [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: 10/21/2021] [Accepted: 02/01/2022] [Indexed: 11/21/2022] Open
Abstract
Actin is an important cytoskeletal protein involved in signal transduction, cell structure and motility. Actin regulators include actin-monomer-binding proteins, Wiskott-Aldrich syndrome (WAS) family of proteins, nucleation proteins, actin filament polymerases and severing proteins. This group of proteins regulate the dynamic changes in actin assembly/disassembly, thus playing an important role in cell motility, intracellular transport, cell division and other basic cellular activities. Lymphocytes are important components of the human immune system, consisting of T-lymphocytes (T cells), B-lymphocytes (B cells) and natural killer cells (NK cells). Lymphocytes are indispensable for both innate and adaptive immunity and cannot function normally without various actin regulators. In this review, we first briefly introduce the structure and fundamental functions of a variety of well-known and newly discovered actin regulators, then we highlight the role of actin regulators in T cell, B cell and NK cell, and finally provide a landscape of various diseases associated with them. This review provides new directions in exploring actin regulators and promotes more precise and effective treatments for related diseases.
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Affiliation(s)
- Jianxuan Sun
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Department and Institute of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xingyu Zhong
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaoyu Fu
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Heather Miller
- Cytek Biosciences, R&D Clinical Reagents, Fremont, CA, United States
| | - Pamela Lee
- Department of Paediatrics and Adolescent Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, Hong Kong SAR, China
| | - Bing Yu
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Chaohong Liu
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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7
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Arve-Butler S, Mossberg A, Schmidt T, Welinder C, Yan H, Berthold E, Król P, Kahn R. Neutrophils Lose the Capacity to Suppress T Cell Proliferation Upon Migration Towards Inflamed Joints in Juvenile Idiopathic Arthritis. Front Immunol 2022; 12:795260. [PMID: 35095871 PMCID: PMC8792960 DOI: 10.3389/fimmu.2021.795260] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 12/23/2021] [Indexed: 02/03/2023] Open
Abstract
Neutrophils are highly abundant in synovial fluid of rheumatic inflamed joints. In oligoarticular juvenile idiopathic arthritis (JIA), synovial fluid neutrophils have impaired effector functions and altered phenotype. We hypothesized that these alterations might impact the immunoregulatory interplay between neutrophils and T cells. In this study we analyzed the suppressive effect of neutrophils, isolated from blood and synovial fluid of oligoarticular JIA patients, on CD4+ T cells activated by CD3/CD28 stimulation. JIA blood neutrophils suppressed T cell proliferation but synovial fluid neutrophils from several patients did not. The loss of T cell suppression was replicated in an in vitro transmigration assay, where healthy control neutrophils migrated into synovial fluid through transwell inserts with endothelial cells and synoviocytes. Non-migrated neutrophils suppressed proliferation of activated CD4+ T cells, but migrated neutrophils had no suppressive effect. Neutrophil suppression of T cells was partly dependent on reactive oxygen species (ROS), demonstrated by impaired suppression in presence of catalase. Migrated neutrophils had reduced ROS production compared to non-migrated neutrophils. A proteomic analysis of transwell-migrated neutrophils identified alterations in proteins related to neutrophil ROS production and degranulation, and biological processes involving protein transport, cell-cell contact and inflammation. In conclusion, neutrophils in synovial fluid of children with JIA have impaired capacity to suppress activated T cells, which may be due to reduced oxidative burst and alterations in proteins related to cell-cell contact and inflammation. The lack of T cell suppression by neutrophils in synovial fluid may contribute to local inflammation and autoimmune reactions in the JIA joint.
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Affiliation(s)
- Sabine Arve-Butler
- Department of Rheumatology, Clinical Sciences Lund, Lund University, Lund, Sweden.,Wallenberg Center for Molecular Medicine, Lund University, Lund, Sweden
| | - Anki Mossberg
- Wallenberg Center for Molecular Medicine, Lund University, Lund, Sweden.,Department of Pediatrics, Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Tobias Schmidt
- Wallenberg Center for Molecular Medicine, Lund University, Lund, Sweden.,Department of Pediatrics, Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Charlotte Welinder
- Department of Clinical Sciences, Division of Oncology, Lund University, Lund, Sweden
| | - Hong Yan
- Swedish National Infrastructure for Biological Mass Spectrometry, Biological Mass Spectrometry (BioMS), Lund, Sweden
| | - Elisabet Berthold
- Department of Rheumatology, Clinical Sciences Lund, Lund University, Lund, Sweden.,Wallenberg Center for Molecular Medicine, Lund University, Lund, Sweden
| | - Petra Król
- Department of Pediatrics, Clinical Sciences Lund, Lund University, Lund, Sweden
| | - Robin Kahn
- Wallenberg Center for Molecular Medicine, Lund University, Lund, Sweden.,Department of Pediatrics, Clinical Sciences Lund, Lund University, Lund, Sweden
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8
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Abstract
Actin filaments and microtubules are cytoskeletal polymers that participate in many vital cell functions including division, morphogenesis, phagocytosis, and motility. Despite the persistent dogma that actin filament and microtubule networks are distinct in localization, structure, and function, a growing body of evidence shows that these elements are choreographed through intricate mechanisms sensitive to either polymer. Many proteins and cellular signals that mediate actin–microtubule interactions have already been identified. However, the impact of these regulators is typically assessed with actin filament or microtubule polymers alone, independent of the other system. Further, unconventional modes and regulators coordinating actin–microtubule interactions are still being discovered. Here we examine several methods of actin–microtubule crosstalk with an emphasis on the molecular links between both polymer systems and their higher-order interactions.
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Affiliation(s)
- Morgan L Pimm
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, NY 13210
| | - Jessica L Henty-Ridilla
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, NY 13210.,Department of Neuroscience and Physiology, SUNY Upstate Medical University, Syracuse, NY 13210
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9
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Wei T, Lambert PF. Role of IQGAP1 in Carcinogenesis. Cancers (Basel) 2021; 13:3940. [PMID: 34439095 PMCID: PMC8391515 DOI: 10.3390/cancers13163940] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 07/28/2021] [Accepted: 08/02/2021] [Indexed: 12/31/2022] Open
Abstract
Scaffolding proteins can play important roles in cell signaling transduction. IQ motif-containing GTPase-activating protein 1 (IQGAP1) influences many cellular activities by scaffolding multiple key signaling pathways, including ones involved in carcinogenesis. Two decades of studies provide evidence that IQGAP1 plays an essential role in promoting cancer development. IQGAP1 is overexpressed in many types of cancer, and its overexpression in cancer is associated with lower survival of the cancer patient. Here, we provide a comprehensive review of the literature regarding the oncogenic roles of IQGAP1. We start by describing the major cancer-related signaling pathways scaffolded by IQGAP1 and their associated cellular activities. We then describe clinical and molecular evidence for the contribution of IQGAP1 in different types of cancers. In the end, we review recent evidence implicating IQGAP1 in tumor-related immune responses. Given the critical role of IQGAP1 in carcinoma development, anti-tumor therapies targeting IQGAP1 or its associated signaling pathways could be beneficial for patients with many types of cancer.
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Affiliation(s)
| | - Paul F. Lambert
- McArdle Laboratory for Cancer Research, Department of Oncology, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA;
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10
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Serum levels of cytoskeleton remodeling proteins and their mRNA expression in tumor tissue of metastatic laryngeal and hypopharyngeal cancers. Mol Biol Rep 2021; 48:5135-5142. [PMID: 34231097 DOI: 10.1007/s11033-021-06510-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 06/21/2021] [Indexed: 12/09/2022]
Abstract
Actin-binding proteins (ABPs) and various signaling systems are involved in the process of squamous cell carcinoma of the larynx and hypopharynx (SCCLH) metastasis. The clinical significance of these proteins has not yet been determined. We analyzed the relationship between the mRNA levels of cofilin 1 (CFL1), profilin 1 (PFN1), adenylyl cyclase-associated protein 1 (CAP1), SNAI1 and RND3 and SCCLH metastasis. The serum levels of the above ABPs were estimated and the relationship between them and their mRNA expressions was analyzed. The expression levels of ABP mRNAs were measured by real-time RT-PCR in paired tissue samples taken from 54 patients with SCCLH (T1-4N0-1M0). Expression analysis was performed using the 2-ΔΔCT method. The levels of ABPs in the blood serum were measured by ELISA. Statistical analysis was carried out using the SPSS Statistica 20.0 software package. No significant difference in the mRNA gene expression in tumor tissue of patients with T1-3N0M0 SCCLH and patients with T2-4N1-2M0 SCCLH was found. High expression of RND3 mRNA was accompanied by an increase in mRNA expression of all studied ABPs. In the blood serum of T2-4N1-2M0 patients, the level of PFN1 was lower by 21% and the level of CAP1 was higher by 75% than those observed in T1-4N0M0 patients. The data obtained showed that RND3 is involved in the regulation of molecular cascades of SCCLH metastasis. PFN1 and CAP1 serum levels can be good classifiers of metastases in patients with SCCLH.
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11
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Ishihara S, Sato T, Sugioka R, Miwa R, Saito H, Sato R, Fukuyama H, Nakajima A, Sawai S, Kotani A, Katagiri K. Rap1 Is Essential for B-Cell Locomotion, Germinal Center Formation and Normal B-1a Cell Population. Front Immunol 2021; 12:624419. [PMID: 34140948 PMCID: PMC8203927 DOI: 10.3389/fimmu.2021.624419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Accepted: 05/17/2021] [Indexed: 11/24/2022] Open
Abstract
Integrin regulation by Rap1 is indispensable for lymphocyte recirculation. In mice having B-cell-specific Rap1a/b double knockouts (DKO), the number of B cells in lymph nodes decreased to approximately 4% of that of control mice, and B cells were present in the spleen and blood. Upon the immunization with NP-CGG, DKO mice demonstrated the defective GC formation in the spleen, and the reduced NP-specific antibody production. In vitro, Rap1 deficiency impaired the movement of activated B cells along the gradients of chemoattractants known to be critical for their localization in the follicles. Furthermore, B-1a cells were almost completely absent in the peritoneal cavity, spleen and blood of adult DKO mice, and the number of B-cell progenitor/precursor (B-p) were reduced in neonatal and fetal livers. However, DKO B-ps normally proliferated, and differentiated into IgM+ cells in the presence of IL-7. CXCL12-dependent migration of B-ps on the VCAM-1 was severely impaired by Rap1 deficiency. Immunostaining study of fetal livers revealed defects in the co-localization of DKO B-ps and IL-7-producing stromal cells. This study proposes that the profound effects of Rap1-deficiency on humoral responses and B-1a cell generation may be due to or in part caused by impairments of the chemoattractant-dependent positioning and the contact with stromal cells.
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Affiliation(s)
- Sayaka Ishihara
- Department of Biosciences, School of Science, Kitasato University, Sagamihara, Japan
| | - Tsuyoshi Sato
- Department of Biosciences, School of Science, Kitasato University, Sagamihara, Japan
| | - Risa Sugioka
- Department of Biosciences, School of Science, Kitasato University, Sagamihara, Japan
| | - Ryota Miwa
- Department of Biosciences, School of Science, Kitasato University, Sagamihara, Japan
| | - Haruka Saito
- Department of Biosciences, School of Science, Kitasato University, Sagamihara, Japan
| | - Ryota Sato
- Laboratory of Lymphocyte Differentiation, RIKEN Center for Integrative Medical Sciences (IMS), Yokohama, Japan
| | - Hidehiro Fukuyama
- Laboratory of Lymphocyte Differentiation, RIKEN Center for Integrative Medical Sciences (IMS), Yokohama, Japan
| | - Akihiko Nakajima
- Department of Basic Science, Graduate School of Arts and Sciences, University of Tokyo, Tokyo, Japan
| | - Satoshi Sawai
- Department of Basic Science, Graduate School of Arts and Sciences, University of Tokyo, Tokyo, Japan
| | - Ai Kotani
- Department of Hematological Malignancy, Institute of Medical Science, Tokai University, Isehara, Japan
| | - Koko Katagiri
- Department of Biosciences, School of Science, Kitasato University, Sagamihara, Japan
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12
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Bolger-Munro M, Choi K, Cheung F, Liu YT, Dang-Lawson M, Deretic N, Keane C, Gold MR. The Wdr1-LIMK-Cofilin Axis Controls B Cell Antigen Receptor-Induced Actin Remodeling and Signaling at the Immune Synapse. Front Cell Dev Biol 2021; 9:649433. [PMID: 33928084 PMCID: PMC8076898 DOI: 10.3389/fcell.2021.649433] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 03/12/2021] [Indexed: 12/27/2022] Open
Abstract
When B cells encounter membrane-bound antigens, the formation and coalescence of B cell antigen receptor (BCR) microclusters amplifies BCR signaling. The ability of B cells to probe the surface of antigen-presenting cells (APCs) and respond to APC-bound antigens requires remodeling of the actin cytoskeleton. Initial BCR signaling stimulates actin-related protein (Arp) 2/3 complex-dependent actin polymerization, which drives B cell spreading as well as the centripetal movement and coalescence of BCR microclusters at the B cell-APC synapse. Sustained actin polymerization depends on concomitant actin filament depolymerization, which enables the recycling of actin monomers and Arp2/3 complexes. Cofilin-mediated severing of actin filaments is a rate-limiting step in the morphological changes that occur during immune synapse formation. Hence, regulators of cofilin activity such as WD repeat-containing protein 1 (Wdr1), LIM domain kinase (LIMK), and coactosin-like 1 (Cotl1) may also be essential for actin-dependent processes in B cells. Wdr1 enhances cofilin-mediated actin disassembly. Conversely, Cotl1 competes with cofilin for binding to actin and LIMK phosphorylates cofilin and prevents it from binding to actin filaments. We now show that Wdr1 and LIMK have distinct roles in BCR-induced assembly of the peripheral actin structures that drive B cell spreading, and that cofilin, Wdr1, and LIMK all contribute to the actin-dependent amplification of BCR signaling at the immune synapse. Depleting Cotl1 had no effect on these processes. Thus, the Wdr1-LIMK-cofilin axis is critical for BCR-induced actin remodeling and for B cell responses to APC-bound antigens.
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Affiliation(s)
- Madison Bolger-Munro
- Department of Microbiology & Immunology and Life Sciences Institute, University of British Columbia, Vancouver, BC, Canada
| | - Kate Choi
- Department of Microbiology & Immunology and Life Sciences Institute, University of British Columbia, Vancouver, BC, Canada
| | - Faith Cheung
- Department of Microbiology & Immunology and Life Sciences Institute, University of British Columbia, Vancouver, BC, Canada
| | - Yi Tian Liu
- Department of Microbiology & Immunology and Life Sciences Institute, University of British Columbia, Vancouver, BC, Canada
| | - May Dang-Lawson
- Department of Microbiology & Immunology and Life Sciences Institute, University of British Columbia, Vancouver, BC, Canada
| | - Nikola Deretic
- Department of Microbiology & Immunology and Life Sciences Institute, University of British Columbia, Vancouver, BC, Canada
| | - Connor Keane
- Department of Microbiology & Immunology and Life Sciences Institute, University of British Columbia, Vancouver, BC, Canada
| | - Michael R Gold
- Department of Microbiology & Immunology and Life Sciences Institute, University of British Columbia, Vancouver, BC, Canada
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13
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Rey-Suarez I, Rogers N, Kerr S, Shroff H, Upadhyaya A. Actomyosin dynamics modulate microtubule deformation and growth during T-cell activation. Mol Biol Cell 2021; 32:1641-1653. [PMID: 33826369 PMCID: PMC8684730 DOI: 10.1091/mbc.e20-10-0685] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Activation of T-cells leads to the formation of immune synapses (ISs) with antigen-presenting cells. This requires T-cell polarization and coordination between the actomyosin and microtubule cytoskeletons. The interactions between these two cytoskeletal components during T-cell activation are not well understood. Here, we elucidate the interactions between microtubules and actin at the IS with high-resolution fluorescence microscopy. We show that microtubule growth dynamics in the peripheral actin-rich region is distinct from that in the central actin-free region. We further demonstrate that these differences arise from differential involvement of Arp2/3- and formin-nucleated actin structures. Formin inhibition results in a moderate decrease in microtubule growth rates, which is amplified in the presence of integrin engagement. In contrast, Arp2/3 inhibition leads to an increase in microtubule growth rates. We find that microtubule filaments are more deformed and exhibit greater shape fluctuations in the periphery of the IS than at the center. Using small molecule inhibitors, we show that actin dynamics and actomyosin contractility play key roles in defining microtubule deformations and shape fluctuations. Our results indicate a mechanical coupling between the actomyosin and microtubule systems during T-cell activation, whereby different actin structures influence microtubule dynamics in distinct ways.
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Affiliation(s)
- Ivan Rey-Suarez
- Institute for Physical Science and Technology, University of Maryland, College Park, MD 20742
| | - Nate Rogers
- Department of Physics, University of Maryland, College Park, MD 20742
| | - Sarah Kerr
- Department of Physics, University of Colorado, Boulder, CO 80302
| | - Hari Shroff
- National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892
| | - Arpita Upadhyaya
- Institute for Physical Science and Technology, University of Maryland, College Park, MD 20742.,Department of Physics, University of Maryland, College Park, MD 20742
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14
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Nieman DC, Groen AJ, Pugachev A, Simonson AJ, Polley K, James K, El-Khodor BF, Varadharaj S, Hernández-Armenta C. Proteomics-Based Detection of Immune Dysfunction in an Elite Adventure Athlete Trekking Across the Antarctica. Proteomes 2020; 8:proteomes8010004. [PMID: 32138228 PMCID: PMC7151708 DOI: 10.3390/proteomes8010004] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 02/29/2020] [Accepted: 03/01/2020] [Indexed: 12/31/2022] Open
Abstract
Proteomics monitoring of an elite adventure athlete (age 33 years) was conducted over a 28-week period that culminated in the successful, solo, unassisted, and unsupported two month trek across the Antarctica (1500 km). Training distress was monitored weekly using a 19-item, validated training distress scale (TDS). Weekly dried blood spot (DBS) specimens were collected via fingerprick blood drops onto standard blood spot cards. DBS proteins were measured with nano-electrospray ionization liquid chromatography tandem mass spectrometry (nanoLC-MS/MS) in data-independent acquisition (DIA) mode, and 712 proteins were identified and quantified. The 28-week period was divided into time segments based on TDS scores, and a contrast analysis between weeks five and eight (low TDS) and between weeks 20 and 23 (high TDS, last month of Antarctica trek) showed that 31 proteins (n = 20 immune related) were upregulated and 35 (n = 17 immune related) were downregulated. Protein-protein interaction (PPI) networks supported a dichotomous immune response. Gene ontology (GO) biological process terms for the upregulated immune proteins showed an increase in regulation of the immune system process, especially inflammation, complement activation, and leukocyte mediated immunity. At the same time, GO terms for the downregulated immune-related proteins indicated a decrease in several aspects of the overall immune system process including neutrophil degranulation and the antimicrobial humoral response. These proteomics data support a dysfunctional immune response in an elite adventure athlete during a sustained period of mental and physical distress while trekking solo across the Antarctica.
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Affiliation(s)
- David C. Nieman
- North Carolina Research Campus, Appalachian State University, Kannapolis, NC 28081, USA;
- Correspondence: ; Tel.: +1-828-773-0056
| | - Arnoud J. Groen
- ProteiQ Biosciences GmbH, 10967 Berlin, Germany; (A.J.G.); (A.P.); (C.H.-A.)
| | - Artyom Pugachev
- ProteiQ Biosciences GmbH, 10967 Berlin, Germany; (A.J.G.); (A.P.); (C.H.-A.)
| | - Andrew J. Simonson
- North Carolina Research Campus, Appalachian State University, Kannapolis, NC 28081, USA;
| | - Kristine Polley
- Standard Process Nutrition Innovation, Kannapolis, NC 28081, USA; (K.P.); (K.J.); (B.F.E.-K.); (S.V.)
| | - Karma James
- Standard Process Nutrition Innovation, Kannapolis, NC 28081, USA; (K.P.); (K.J.); (B.F.E.-K.); (S.V.)
| | - Bassem F. El-Khodor
- Standard Process Nutrition Innovation, Kannapolis, NC 28081, USA; (K.P.); (K.J.); (B.F.E.-K.); (S.V.)
| | - Saradhadevi Varadharaj
- Standard Process Nutrition Innovation, Kannapolis, NC 28081, USA; (K.P.); (K.J.); (B.F.E.-K.); (S.V.)
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15
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Spolitu S, Okamoto H, Dai W, Zadroga JA, Wittchen ES, Gromada J, Ozcan L. Hepatic Glucagon Signaling Regulates PCSK9 and Low-Density Lipoprotein Cholesterol. Circ Res 2019; 124:38-51. [PMID: 30582457 DOI: 10.1161/circresaha.118.313648] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
RATIONALE Glucagon is a key hormone that regulates the adaptive metabolic responses to fasting. In addition to maintaining glucose homeostasis, glucagon participates in the regulation of cholesterol metabolism; however, the molecular pathways underlying this effect are incompletely understood. OBJECTIVE We sought to determine the role of hepatic Gcgr (glucagon receptor) signaling in plasma cholesterol regulation and identify its underlying molecular mechanisms. METHODS AND RESULTS We show that Gcgr signaling plays an essential role in LDL-C (low-density lipoprotein cholesterol) homeostasis through regulating the PCSK9 (proprotein convertase subtilisin/kexin type 9) levels. Silencing of hepatic Gcgr or inhibition of glucagon action increased hepatic and plasma PCSK9 and resulted in lower LDLR (LDL receptor) protein and increased plasma LDL-C. Conversely, treatment of wild-type (WT) mice with glucagon lowered LDL-C levels, whereas this response was abrogated in Pcsk9-/- and Ldlr-/- mice. Our gain- and loss-of-function studies identified Epac2 (exchange protein activated by cAMP-2) and Rap1 (Ras-related protein-1) as the downstream mediators of glucagon's action on PCSK9 homeostasis. Moreover, mechanistic studies revealed that glucagon affected the half-life of PCSK9 protein without changing the level of its mRNA, indicating that Gcgr signaling regulates PCSK9 degradation. CONCLUSIONS These findings provide novel insights into the molecular interplay between hepatic glucagon signaling and lipid metabolism and describe a new posttranscriptional mechanism of PCSK9 regulation.
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Affiliation(s)
- Stefano Spolitu
- From the Department of Medicine, Columbia University, New York (S.S., W.D., J.A.Z., L.O.)
| | - Haruka Okamoto
- Regeneron Pharmaceuticals, Inc, Tarrytown, NY (H.O., J.G.)
| | - Wen Dai
- From the Department of Medicine, Columbia University, New York (S.S., W.D., J.A.Z., L.O.)
| | - John A Zadroga
- From the Department of Medicine, Columbia University, New York (S.S., W.D., J.A.Z., L.O.)
| | - Erika S Wittchen
- Department of Cell Biology and Physiology, University of North Carolina, Chapel Hill (E.S.W.)
| | - Jesper Gromada
- Regeneron Pharmaceuticals, Inc, Tarrytown, NY (H.O., J.G.)
| | - Lale Ozcan
- From the Department of Medicine, Columbia University, New York (S.S., W.D., J.A.Z., L.O.)
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16
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Bolger-Munro M, Choi K, Scurll JM, Abraham L, Chappell RS, Sheen D, Dang-Lawson M, Wu X, Priatel JJ, Coombs D, Hammer JA, Gold MR. Arp2/3 complex-driven spatial patterning of the BCR enhances immune synapse formation, BCR signaling and B cell activation. eLife 2019; 8:e44574. [PMID: 31157616 PMCID: PMC6591008 DOI: 10.7554/elife.44574] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 06/01/2019] [Indexed: 12/17/2022] Open
Abstract
When B cells encounter antigens on the surface of an antigen-presenting cell (APC), B cell receptors (BCRs) are gathered into microclusters that recruit signaling enzymes. These microclusters then move centripetally and coalesce into the central supramolecular activation cluster of an immune synapse. The mechanisms controlling BCR organization during immune synapse formation, and how this impacts BCR signaling, are not fully understood. We show that this coalescence of BCR microclusters depends on the actin-related protein 2/3 (Arp2/3) complex, which nucleates branched actin networks. Moreover, in murine B cells, this dynamic spatial reorganization of BCR microclusters amplifies proximal BCR signaling reactions and enhances the ability of membrane-associated antigens to induce transcriptional responses and proliferation. Our finding that Arp2/3 complex activity is important for B cell responses to spatially restricted membrane-bound antigens, but not for soluble antigens, highlights a critical role for Arp2/3 complex-dependent actin remodeling in B cell responses to APC-bound antigens.
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Affiliation(s)
- Madison Bolger-Munro
- Department of Microbiology and ImmunologyUniversity of British ColumbiaVancouverCanada
- Life Sciences Institute, I3 Research GroupUniversity of British ColumbiaVancouverCanada
| | - Kate Choi
- Department of Microbiology and ImmunologyUniversity of British ColumbiaVancouverCanada
- Life Sciences Institute, I3 Research GroupUniversity of British ColumbiaVancouverCanada
| | - Joshua M Scurll
- Department of Mathematics, Institute of Applied MathematicsUniversity of British ColumbiaVancouverCanada
| | - Libin Abraham
- Department of Microbiology and ImmunologyUniversity of British ColumbiaVancouverCanada
- Life Sciences Institute, I3 Research GroupUniversity of British ColumbiaVancouverCanada
- Department of Mathematics, Institute of Applied MathematicsUniversity of British ColumbiaVancouverCanada
| | - Rhys S Chappell
- Department of Mathematics, Institute of Applied MathematicsUniversity of British ColumbiaVancouverCanada
| | - Duke Sheen
- Department of Microbiology and ImmunologyUniversity of British ColumbiaVancouverCanada
- Life Sciences Institute, I3 Research GroupUniversity of British ColumbiaVancouverCanada
| | - May Dang-Lawson
- Department of Microbiology and ImmunologyUniversity of British ColumbiaVancouverCanada
- Life Sciences Institute, I3 Research GroupUniversity of British ColumbiaVancouverCanada
| | - Xufeng Wu
- Cell Biology and Physiology CenterNational Heart, Lung and Blood Institute, National Institutes of HealthBethesdaUnited States
| | - John J Priatel
- Department of Pathology and Laboratory MedicineUniversity of British ColumbiaVancouverCanada
- BC Children’s Hospital Research InstituteVancouverCanada
| | - Daniel Coombs
- Department of Mathematics, Institute of Applied MathematicsUniversity of British ColumbiaVancouverCanada
| | - John A Hammer
- Cell Biology and Physiology CenterNational Heart, Lung and Blood Institute, National Institutes of HealthBethesdaUnited States
| | - Michael R Gold
- Department of Microbiology and ImmunologyUniversity of British ColumbiaVancouverCanada
- Life Sciences Institute, I3 Research GroupUniversity of British ColumbiaVancouverCanada
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17
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Woo JAA, Liu T, Fang CC, Cazzaro S, Kee T, LePochat P, Yrigoin K, Penn C, Zhao X, Wang X, Liggett SB, Kang DE. Activated cofilin exacerbates tau pathology by impairing tau-mediated microtubule dynamics. Commun Biol 2019; 2:112. [PMID: 30911686 PMCID: PMC6430779 DOI: 10.1038/s42003-019-0359-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Accepted: 02/15/2019] [Indexed: 12/27/2022] Open
Abstract
Alzheimer's disease (AD) is a progressive neurodegenerative disorder and the most common form of dementia. While the accumulation of Aβ is pivotal to the etiology of AD, both the microtubule-associated protein tau (MAPT) and the F-actin severing protein cofilin are necessary for the deleterious effects of Aβ. However, the molecular link between tau and cofilin remains unclear. In this study, we found that cofilin competes with tau for direct microtubule binding in vitro, in cells, and in vivo, which inhibits tau-induced microtubule assembly. Genetic reduction of cofilin mitigates tauopathy and synaptic defects in Tau-P301S mice and movement deficits in tau transgenic C. elegans. The pathogenic effects of cofilin are selectively mediated by activated cofilin, as active but not inactive cofilin selectively interacts with tubulin, destabilizes microtubules, and promotes tauopathy. These results therefore indicate that activated cofilin plays an essential intermediary role in neurotoxic signaling that promotes tauopathy.
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Affiliation(s)
- Jung-A. A. Woo
- USF Health Byrd Alzheimer’s Institute, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
- Department of Molecular Pharmacology and Physiology, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
| | - Tian Liu
- USF Health Byrd Alzheimer’s Institute, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
- Department of Molecular Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
| | - Cenxiao C. Fang
- USF Health Byrd Alzheimer’s Institute, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
- Department of Molecular Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
| | - Sara Cazzaro
- USF Health Byrd Alzheimer’s Institute, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
- Department of Molecular Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
| | - Teresa Kee
- USF Health Byrd Alzheimer’s Institute, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
| | - Patrick LePochat
- USF Health Byrd Alzheimer’s Institute, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
- Department of Molecular Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
| | - Ksenia Yrigoin
- USF Health Byrd Alzheimer’s Institute, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
| | - Courtney Penn
- USF Health Byrd Alzheimer’s Institute, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
- Department of Molecular Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
| | - Xingyu Zhao
- USF Health Byrd Alzheimer’s Institute, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
- Department of Molecular Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
| | - Xinming Wang
- USF Health Byrd Alzheimer’s Institute, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
| | - Stephen B. Liggett
- USF Health Byrd Alzheimer’s Institute, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
- Department of Molecular Pharmacology and Physiology, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
| | - David E. Kang
- USF Health Byrd Alzheimer’s Institute, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
- Department of Molecular Medicine, University of South Florida, Morsani College of Medicine, Tampa, FL 33613 USA
- James A. Haley Veteran’s Administration Hospital, Tampa, FL 33612 USA
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18
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Li J, Yin W, Jing Y, Kang D, Yang L, Cheng J, Yu Z, Peng Z, Li X, Wen Y, Sun X, Ren B, Liu C. The Coordination Between B Cell Receptor Signaling and the Actin Cytoskeleton During B Cell Activation. Front Immunol 2019; 9:3096. [PMID: 30687315 PMCID: PMC6333714 DOI: 10.3389/fimmu.2018.03096] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2018] [Accepted: 12/13/2018] [Indexed: 01/27/2023] Open
Abstract
B-cell activation plays a crucial part in the immune system and is initiated via interaction between the B cell receptor (BCR) and specific antigens. In recent years with the help of modern imaging techniques, it was found that the cortical actin cytoskeleton changes dramatically during B-cell activation. In this review, we discuss how actin-cytoskeleton reorganization regulates BCR signaling in different stages of B-cell activation, specifically when stimulated by antigens, and also how this reorganization is mediated by BCR signaling molecules. Abnormal BCR signaling is associated with the progression of lymphoma and immunological diseases including autoimmune disorders, and recent studies have proved that impaired actin cytoskeleton can devastate the normal activation of B cells. Therefore, to figure out the coordination between the actin cytoskeleton and BCR signaling may reveal an underlying mechanism of B-cell activation, which has potential for new treatments for B-cell associated diseases.
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Affiliation(s)
- Jingwen Li
- Department of Microbiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Wei Yin
- Wuhan Children's Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yukai Jing
- Department of Microbiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Danqing Kang
- Department of Microbiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Lu Yang
- Department of Microbiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jiali Cheng
- Department of Microbiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Ze Yu
- Department of Microbiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zican Peng
- Department of Microbiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xingbo Li
- Department of Microbiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yue Wen
- Department of Microbiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xizi Sun
- Department of Microbiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Boxu Ren
- Department of Immunology, School of Medicine, Yangtze University, Jingzhou, China
- Clinical Molecular Immunology Center, School of Medicine, Yangtze University, Jingzhou, China
| | - Chaohong Liu
- Department of Microbiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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19
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Lim WM, Ito Y, Sakata-Sogawa K, Tokunaga M. CLIP-170 is essential for MTOC repositioning during T cell activation by regulating dynein localisation on the cell surface. Sci Rep 2018; 8:17447. [PMID: 30487641 PMCID: PMC6261991 DOI: 10.1038/s41598-018-35593-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 11/06/2018] [Indexed: 02/02/2023] Open
Abstract
The microtubule-organizing centre (MTOC) is repositioned to the centre of the contacted cell surface, the immunological synapse, during T cell activation. However, our understanding of its molecular mechanism remains limited. Here, we found that the microtubule plus-end tracking cytoplasmic linker protein 170 (CLIP-170) plays a novel role in MTOC repositioning using fluorescence imaging. Inhibition of CLIP-170 phosphorylation impaired both MTOC repositioning and interleukin-2 (IL-2) expression. T cell stimulation induced some fraction of dynein to colocalise with CLIP-170 and undergo plus-end tracking. Concurrently, it increased dynein in minus-end-directed movement. It also increased dynein relocation to the centre of the contact surface. Dynein not colocalised with CLIP-170 showed both an immobile state and minus-end-directed movement at a velocity in good agreement with the velocity of MTOC repositioning, which suggests that dynein at the immunological synapse may pull the microtubules and the MTOC. Although CLIP-170 is phosphorylated by AMP-activated protein kinase (AMPK) irrespective of stimulation, phosphorylated CLIP-170 is essential for dynein recruitment to plus-end tracking and for dynein relocation. This indicates that dynein relocation results from coexistence of plus-end- and minus-end-directed translocation. In conclusion, CLIP-170 plays an indispensable role in MTOC repositioning and full activation of T cells by regulating dynein localisation.
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Affiliation(s)
- Wei Ming Lim
- School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho, Midori, Yokohama, Kanagawa, 226-8501, Japan
| | - Yuma Ito
- School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho, Midori, Yokohama, Kanagawa, 226-8501, Japan
| | - Kumiko Sakata-Sogawa
- School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho, Midori, Yokohama, Kanagawa, 226-8501, Japan.
| | - Makio Tokunaga
- School of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta-cho, Midori, Yokohama, Kanagawa, 226-8501, Japan.
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20
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Abel AM, Tiwari AA, Gerbec ZJ, Siebert JR, Yang C, Schloemer NJ, Dixon KJ, Thakar MS, Malarkannan S. IQ Domain-Containing GTPase-Activating Protein 1 Regulates Cytoskeletal Reorganization and Facilitates NKG2D-Mediated Mechanistic Target of Rapamycin Complex 1 Activation and Cytokine Gene Translation in Natural Killer Cells. Front Immunol 2018; 9:1168. [PMID: 29892299 PMCID: PMC5985319 DOI: 10.3389/fimmu.2018.01168] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Accepted: 05/09/2018] [Indexed: 12/25/2022] Open
Abstract
Natural killer (NK) cells are innate lymphocytes that play essential roles in mediating antitumor immunity. NK cells respond to various inflammatory stimuli including cytokines and stress-induced cellular ligands which activate germline-encoded activation receptors (NKRs), such as NKG2D. The signaling molecules activated downstream of NKRs are well defined; however, the mechanisms that regulate these pathways are not fully understood. IQ domain-containing GTPase-activating protein 1 (IQGAP1) is a ubiquitously expressed scaffold protein. It regulates diverse cellular signaling programs in various physiological contexts, including immune cell activation and function. Therefore, we sought to investigate the role of IQGAP1 in NK cells. Development and maturation of NK cells from mice lacking IQGAP1 (Iqgap1-/- ) were mostly intact; however, the absolute number of splenic NK cells was significantly reduced. Phenotypic and functional characterization revealed a significant reduction in the egression of NK cells from the bone marrow of Iqagp1-/- mice altering their peripheral homeostasis. Lack of IQGAP1 resulted in reduced NK cell motility and their ability to mediate antitumor immunity in vivo. Activation of Iqgap1-/- NK cells via NKRs, including NKG2D, resulted in significantly reduced levels of inflammatory cytokines compared with wild-type (WT). This reduction in Iqgap1-/- NK cells is neither due to an impaired membrane proximal signaling nor a defect in gene transcription. The levels of Ifng transcripts were comparable between WT and Iqgap1-/- , suggesting that IQGAP1-dependent regulation of cytokine production is regulated by a post-transcriptional mechanism. To this end, Iqgap1-/- NK cells failed to fully induce S6 phosphorylation and showed significantly reduced protein translation following NKG2D-mediated activation, revealing a previously undefined regulatory function of IQGAP1 via the mechanistic target of rapamycin complex 1. Together, these results implicate IQGAP1 as an essential scaffold for NK cell homeostasis and function and provide novel mechanistic insights to the post-transcriptional regulation of inflammatory cytokine production.
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Affiliation(s)
- Alex M Abel
- Department of Microbiology and Immunology, Medical College of Wisconsin, Milwaukee, WI, United States.,Laboratory of Molecular Immunology and Immunotherapy, Blood Research Institute, Milwaukee, WI, United States
| | - Aradhana A Tiwari
- Laboratory of Molecular Immunology and Immunotherapy, Blood Research Institute, Milwaukee, WI, United States
| | - Zachary J Gerbec
- Department of Microbiology and Immunology, Medical College of Wisconsin, Milwaukee, WI, United States.,Laboratory of Molecular Immunology and Immunotherapy, Blood Research Institute, Milwaukee, WI, United States
| | - Jason R Siebert
- Department of Microbiology and Immunology, Medical College of Wisconsin, Milwaukee, WI, United States.,Laboratory of Molecular Immunology and Immunotherapy, Blood Research Institute, Milwaukee, WI, United States
| | - Chao Yang
- Department of Microbiology and Immunology, Medical College of Wisconsin, Milwaukee, WI, United States.,Laboratory of Molecular Immunology and Immunotherapy, Blood Research Institute, Milwaukee, WI, United States
| | - Nathan J Schloemer
- Laboratory of Molecular Immunology and Immunotherapy, Blood Research Institute, Milwaukee, WI, United States.,Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Kate J Dixon
- Department of Microbiology and Immunology, Medical College of Wisconsin, Milwaukee, WI, United States.,Laboratory of Molecular Immunology and Immunotherapy, Blood Research Institute, Milwaukee, WI, United States
| | - Monica S Thakar
- Laboratory of Molecular Immunology and Immunotherapy, Blood Research Institute, Milwaukee, WI, United States.,Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Subramaniam Malarkannan
- Department of Microbiology and Immunology, Medical College of Wisconsin, Milwaukee, WI, United States.,Laboratory of Molecular Immunology and Immunotherapy, Blood Research Institute, Milwaukee, WI, United States.,Department of Medicine, Medical College of Wisconsin, Milwaukee, WI, United States
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21
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Wang JC, Bolger-Munro M, Gold MR. Visualizing the Actin and Microtubule Cytoskeletons at the B-cell Immune Synapse Using Stimulated Emission Depletion (STED) Microscopy. J Vis Exp 2018. [PMID: 29683438 DOI: 10.3791/57028] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
B cells that bind to membrane-bound antigens (e.g., on the surface of an antigen-presenting cell) form an immune synapse, a specialized cellular structure that optimizes B-cell receptor (BCR) signaling and BCR-mediated antigen acquisition. Both the remodeling of the actin cytoskeleton and the reorientation of the microtubule network towards the antigen contact site are essential for immune synapse formation. Remodeling of the actin cytoskeleton into a dense peripheral ring of F-actin is accompanied by polarization of the microtubule-organizing center towards the immune synapse. Microtubule plus-end binding proteins, as well as cortical plus-end capture proteins mediate physical interactions between the actin and microtubule cytoskeletons, which allow them to be reorganized in a coordinated manner. Elucidating the mechanisms that control this cytoskeletal reorganization, as well as understanding how these cytoskeletal structures shape immune synapse formation and BCR signaling, can provide new insights into B cell activation. This has been aided by the development of super-resolution microscopy approaches that reveal new details of cytoskeletal network organization. We describe here a method for using stimulated emission depletion (STED) microscopy to simultaneously image actin structures, microtubules, and transfected GFP-tagged microtubule plus-end binding proteins in B cells. To model the early events in immune synapse formation, we allow B cells to spread on coverslips coated with anti-immunoglobulin (anti-Ig) antibodies, which initiate BCR signaling and cytoskeleton remodeling. We provide step-by-step protocols for expressing GFP fusion proteins in A20 B-lymphoma cells, for anti-Ig-induced cell spreading, and for subsequent cell fixation, Immunostaining, image acquisition, and image deconvolution steps. The high-resolution images obtained using these procedures allow one to simultaneously visualize actin structures, microtubules, and the microtubule plus-end binding proteins that may link these two cytoskeletal networks.
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Affiliation(s)
- Jia C Wang
- Department of Microbiology and Immunology, University of British Columbia
| | | | - Michael R Gold
- Department of Microbiology and Immunology, University of British Columbia;
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22
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Zhang X, Cao S, Barila G, Edreira MM, Hong K, Wankhede M, Naim N, Buck M, Altschuler DL. Cyclase-associated protein 1 (CAP1) is a prenyl-binding partner of Rap1 GTPase. J Biol Chem 2018; 293:7659-7673. [PMID: 29618512 DOI: 10.1074/jbc.ra118.001779] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 02/22/2018] [Indexed: 12/20/2022] Open
Abstract
Rap1 proteins are members of the Ras subfamily of small GTPases involved in many biological responses, including adhesion, cell proliferation, and differentiation. Like all small GTPases, they work as molecular allosteric units that are active in signaling only when associated with the proper membrane compartment. Prenylation, occurring in the cytosol, is an enzymatic posttranslational event that anchors small GTPases at the membrane, and prenyl-binding proteins are needed to mask the cytoplasm-exposed lipid during transit to the target membrane. However, several of these proteins still await discovery. In this study, we report that cyclase-associated protein 1 (CAP1) binds Rap1. We found that this binding is GTP-independent, does not involve Rap1's effector domain, and is fully contained in its C-terminal hypervariable region (HVR). Furthermore, Rap1 prenylation was required for high-affinity interactions with CAP1 in a geranylgeranyl-specific manner. The prenyl binding specifically involved CAP1's C-terminal hydrophobic β-sheet domain. We present a combination of experimental and computational approaches, yielding a model whereby the high-affinity binding between Rap1 and CAP1 involves electrostatic and nonpolar side-chain interactions between Rap1's HVR residues, lipid, and CAP1 β-sheet domain. The binding was stabilized by the lipid insertion into the β-solenoid whose interior was occupied by nonpolar side chains. This model was reminiscent of the recently solved structure of the PDEδ-K-Ras complex; accordingly, disruptors of this complex, e.g. deltarasin, blocked the Rap1-CAP1 interaction. These findings indicate that CAP1 is a geranylgeranyl-binding partner of Rap1.
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Affiliation(s)
- Xuefeng Zhang
- From the Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261 and
| | - Shufen Cao
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, Ohio 44116
| | - Guillermo Barila
- From the Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261 and
| | - Martin M Edreira
- From the Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261 and
| | - Kyoungja Hong
- From the Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261 and
| | - Mamta Wankhede
- From the Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261 and
| | - Nyla Naim
- From the Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261 and
| | - Matthias Buck
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, Ohio 44116
| | - Daniel L Altschuler
- From the Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261 and
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23
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Wang JC, Lee JYJ, Dang-Lawson M, Pritchard C, Gold MR. The Rap2c GTPase facilitates B cell receptor-induced reorientation of the microtubule-organizing center. Small GTPases 2018; 11:402-412. [PMID: 29457987 DOI: 10.1080/21541248.2018.1441626] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
When B lymphocytes encounter antigen-bearing surfaces, B-cell receptor (BCR) signaling initiates remodeling of the F-actin network and reorientation of the microtubule-organizing center (MTOC) towards the antigen contact site. We have previously shown that the Rap1 GTPase, an evolutionarily conserved regulator of cell polarity, is essential for these processes and that Rap1-regulated actin remodeling is required for MTOC polarization. The role of Rap2 proteins in establishing cell polarity is not well understood. We now show that depleting Rap2c, the only Rap2 isoform expressed in the A20 B-cell line, impairs BCR-induced MTOC reorientation as well as the actin remodeling that supports MTOC polarization. Thus Rap1 and Rap2 proteins may have similar but non-redundant functions in coupling the BCR to MTOC polarization.
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Affiliation(s)
- Jia C Wang
- Department of Microbiology & Immunology and the Life Sciences Institute, University of British Columbia , Vancouver, BC, Canada
| | - Jeff Y-J Lee
- Department of Microbiology & Immunology and the Life Sciences Institute, University of British Columbia , Vancouver, BC, Canada
| | - May Dang-Lawson
- Department of Microbiology & Immunology and the Life Sciences Institute, University of British Columbia , Vancouver, BC, Canada
| | - Caitlin Pritchard
- Department of Microbiology & Immunology and the Life Sciences Institute, University of British Columbia , Vancouver, BC, Canada
| | - Michael R Gold
- Department of Microbiology & Immunology and the Life Sciences Institute, University of British Columbia , Vancouver, BC, Canada
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24
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Schirmer B, Giehl K, Kubatzky KF. Report of the Signal Transduction Society Meeting 2017-Metabolism in Health and Disease. Int J Mol Sci 2018; 19:ijms19020549. [PMID: 29439515 PMCID: PMC5855771 DOI: 10.3390/ijms19020549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 01/31/2018] [Accepted: 02/01/2018] [Indexed: 11/16/2022] Open
Abstract
The annual “Joint Meeting Signal Transduction—Receptors, Mediators and Genes” of the Signal Transduction Society (STS) aims to be an interdisciplinary forum for researchers who share a common interest in deciphering signal transduction pathways in normal or transformed cells, in health and disease, in humans and animal models, or in plants or bacteria. The special focus of the 21st annual Joint Meeting, which took place from 8–10 November 2017 in Weimar, was the topic “Metabolism in Health and Disease” and covered multiple aspects of this highly exciting and fast developing research field. Invited keynote speakers introduced the impact of metabolism on tumor immunology, immune cell signaling, and posttranslational modifications in three specific workshops to the audience. Various other aspects of signal transduction were intensively discussed in five additional workshops. Here, we give an overview of the various workshops and further aspects of the scientific program.
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Affiliation(s)
- Bastian Schirmer
- Institut für Pharmakologie, Medizinische Hochschule Hannover, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
| | - Klaudia Giehl
- Signaltransduktion Zellulärer Motilität, Innere Medizin V, Justus-Liebig-Universität Giessen, Aulweg 128, 35392 Giessen, Germany.
| | - Katharina F Kubatzky
- Zentrum für Infektiologie, Medizinische Mikrobiologie und Hygiene, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany.
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25
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Wang JC, Bolger-Munro M, Gold MR. Imaging the Interactions Between B Cells and Antigen-Presenting Cells. Methods Mol Biol 2018; 1707:131-161. [PMID: 29388105 DOI: 10.1007/978-1-4939-7474-0_10] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In vivo, B cells are often activated by antigens that are displayed on the surface of antigen-presenting cells (APCs). Binding of membrane-associated antigens to the B cell receptor (BCR) causes rapid cytoskeleton-dependent changes in the spatial organization of the BCR and other B cell membrane proteins, leading to the formation of an immune synapse. This process has been modeled using antigens attached to artificial planar lipid bilayers or to plasma membrane sheets. As a more physiological system for studying B cell-APC interactions, we have expressed model antigens in easily transfected adherent cell lines such as Cos-7 cells. The model antigens that we have used are a transmembrane form of a single-chain anti-Igκ antibody and a transmembrane form of hen egg lysozyme that is fused to a fluorescent protein. This has allowed us to study multiple aspects of B cell immune synapse formation including cytoskeletal reorganization, BCR microcluster coalescence, BCR-mediated antigen gathering, and BCR signaling. Here, we provide protocols for expressing these model antigens on the surface of Cos-7 cells, transfecting B cells with siRNAs or with plasmids encoding fluorescent proteins, using fixed cell and live cell fluorescence microscopy to image B cell-APC interactions, and quantifying APC-induced changes in BCR spatial organization and signaling.
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Affiliation(s)
- Jia C Wang
- Department of Microbiology & Immunology and the Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Madison Bolger-Munro
- Department of Microbiology & Immunology and the Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Michael R Gold
- Department of Microbiology & Immunology and the Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC, V6T 1Z3, Canada.
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