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Wang P, Li Y, Sun Y, Xu T. EFHD2 cooperates with E3 ubiquitin ligase Smurf1 to facilitate virus infection by promoting the degradation of TRAF6 in teleost fish. J Virol 2024; 98:e0117623. [PMID: 38054609 PMCID: PMC10805015 DOI: 10.1128/jvi.01176-23] [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: 07/30/2023] [Accepted: 11/20/2023] [Indexed: 12/07/2023] Open
Abstract
The ubiquitin-proteasome system is one of the most important protein stability regulation systems. It can precisely regulate host immune responses by targeting signaling proteins. TRAF6 is a crucial E3 ubiquitin ligase in host antiviral signaling pathway. Here, we discovered that EF-hand domain-containing protein D2 (EFHD2) collaborated with the E3 ubiquitin ligase Smurf1 to potentiate the degradation of TRAF6, hence facilitating RNA virus Siniperca chuatsi rhabdovirus infection. The mechanism analysis revealed that EFHD2 interacted with Smurf1 and enhanced its protein stability by impairing K48-linked polyubiquitination of Smurf1, thereby promoting Smurf1-catalyzed degradation of TRAF6. This study initially demonstrated a novel mechanism by which viruses utilize host EFHD2 to achieve immune escape and provided a new perspective on the exploration of mammalian innate immunity.IMPORTANCEViruses induce host cells to activate several antiviral signaling pathways. TNF receptor-associated factor 6 (TRAF6) plays an essential role in these pathways. Numerous studies have been done on the mechanisms of TRAF6-mediated resistance to viral invasion. However, little is known about the strategies that viruses employ to antagonize TRAF6-mediated antiviral signaling pathway. Here, we discovered that EFHD2 functions as a host factor to promote viral replication. Mechanistically, EFHD2 potentiates Smurf1 to catalyze the ubiquitin-proteasomal degradation of TRAF6 by promoting the deubiquitination and stability of Smurf1, which in turn inhibits the production of proinflammatory cytokines and interferons. Our study also provides a new perspective on mammalian resistance to viral invasion.
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Affiliation(s)
- Pengfei Wang
- Laboratory of Fish Molecular Immunology, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China
| | - Ye Li
- Laboratory of Fish Molecular Immunology, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China
| | - Yuena Sun
- Laboratory of Fish Molecular Immunology, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China
- Laboratory of Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
- Key Laboratory of Freshwater Aquatic Genetic Resources, Ministry of Agriculture and Rural Affairs, Shanghai Ocean University, Shanghai, China
| | - Tianjun Xu
- Laboratory of Fish Molecular Immunology, College of Fisheries and Life Science, Shanghai Ocean University, Shanghai, China
- Laboratory of Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
- National Pathogen Collection Center for Aquatic Animals, Shanghai Ocean University, Shanghai, China
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2
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Zuo W, Tian M, Qi J, Zhang G, Hu J, Wang S, Bao Y. The functions of EF-hand proteins from host and zoonotic pathogens. Microbes Infect 2023:105276. [PMID: 38072184 DOI: 10.1016/j.micinf.2023.105276] [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: 11/08/2023] [Revised: 12/05/2023] [Accepted: 12/06/2023] [Indexed: 12/24/2023]
Abstract
EF-hand proteins not only regulate biological processes, but also influence immunity and infection. In this review, we summarize EF-hand proteins' functions in host and zoonotic pathogens, with details in structures, Ca2+ affinity, downstream targets and functional mechanisms. Studies entitled as EF-hand-related but with less solid features were also discussed. We believe it could raise cautions and facilitate proper research strategy for researchers.
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Affiliation(s)
- Wei Zuo
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Mingxing Tian
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Jingjing Qi
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Guangdong Zhang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Jiangang Hu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China
| | - Shaohui Wang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; Engineering Research Center for the Prevention and Control of Animal Original Zoonosis of Fujian Province University, College of Life Science, Longyan University, Longyan, 364012, Fujian, China.
| | - Yanqing Bao
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Shanghai 200241, China; Engineering Research Center for the Prevention and Control of Animal Original Zoonosis of Fujian Province University, College of Life Science, Longyan University, Longyan, 364012, Fujian, China.
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3
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Sołtys K, Tarczewska A, Bystranowska D. Modulation of biomolecular phase behavior by metal ions. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2023; 1870:119567. [PMID: 37582439 DOI: 10.1016/j.bbamcr.2023.119567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 08/04/2023] [Accepted: 08/08/2023] [Indexed: 08/17/2023]
Abstract
Liquid-liquid phase separation (LLPS) appears to be a newly appreciated aspect of the cellular organization of biomolecules that leads to the formation of membraneless organelles (MLOs). MLOs generate distinct microenvironments where particular biomolecules are highly concentrated compared to those in the surrounding environment. Their thermodynamically driven formation is reversible, and their liquid nature allows them to fuse with each other. Dysfunctional biomolecular condensation is associated with human diseases. Pathological states of MLOs may originate from the mutation of proteins or may be induced by other factors. In most aberrant MLOs, transient interactions are replaced by stronger and more rigid interactions, preventing their dissolution, and causing their uncontrolled growth and dysfunction. For these reasons, there is great interest in identifying factors that modulate LLPS. In this review, we discuss an enigmatic and mostly unexplored aspect of this process, namely, the regulatory effects of metal ions on the phase behavior of biomolecules.
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Affiliation(s)
- Katarzyna Sołtys
- Department of Biochemistry, Molecular Biology and Biotechnology, Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland.
| | - Aneta Tarczewska
- Department of Biochemistry, Molecular Biology and Biotechnology, Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland
| | - Dominika Bystranowska
- Department of Biochemistry, Molecular Biology and Biotechnology, Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland
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4
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Lehne F, Bogdan S. Getting cells into shape by calcium-dependent actin cross-linking proteins. Front Cell Dev Biol 2023; 11:1171930. [PMID: 37025173 PMCID: PMC10070769 DOI: 10.3389/fcell.2023.1171930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 03/09/2023] [Indexed: 04/08/2023] Open
Abstract
The actin cytoskeleton represents a highly dynamic filament system providing cell structure and mechanical forces to drive a variety of cellular processes. The dynamics of the actin cytoskeleton are controlled by a number of conserved proteins that maintain the pool of actin monomers, promote actin nucleation, restrict the length of actin filaments and cross-link filaments into networks or bundles. Previous work has been established that cytoplasmic calcium is an important signal to rapidly relay information to the actin cytoskeleton, but the underlying mechanisms remain poorly understood. Here, we summarize new recent perspectives on how calcium fluxes are transduced to the actin cytoskeleton in a physiological context. In this mini-review we will focus on three calcium-binding EF-hand-containing actin cross-linking proteins, α-actinin, plastin and EFHD2/Swiprosin-1, and how these conserved proteins affect the cell's actin reorganization in the context of cell migration and wound closure in response to calcium.
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5
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Thylur Puttalingaiah R. Role of Swiprosin-1/EFHD2 as a biomarker in the development of chronic diseases. Life Sci 2022; 297:120462. [PMID: 35276221 DOI: 10.1016/j.lfs.2022.120462] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 03/01/2022] [Accepted: 03/02/2022] [Indexed: 10/18/2022]
Abstract
Swiprosin-1 or EFHD2, is a Ca2+ binding actin protein and its expression has been shown to be distinct in various cell types. The expression of swiprosin-1 is upregulated during the activation of immune cells, epithelial and endothelial cells. The expression of swiprosin-1 is regulated by diverse signaling pathways that are contingent upon the specific type of cells. The aim of this review is to summarize and provide an overview of the role of swiprosin-1 in pathophysiological conditions of cancers, cardiovascular diseases, diabetic nephropathy, neuropsychiatric diseases, and in the process of inflammation, immune response, and inflammatory diseases. Novel approaches for the targeting of swiprosin-1 as a biomarker in the early detection and prevention of various development of chronic diseases are also explored.
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Affiliation(s)
- Ramesh Thylur Puttalingaiah
- Stanley S. Scott Cancer Center, Louisiana State University Health Sciences Center, 1700 Tulane Avenue, Room 945-B1, New Orleans, LA 70112, USA..
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6
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Reimer D, Meyer-Hermann M, Rakhymzhan A, Steinmetz T, Tripal P, Thomas J, Boettcher M, Mougiakakos D, Schulz SR, Urbanczyk S, Hauser AE, Niesner RA, Mielenz D. B Cell Speed and B-FDC Contacts in Germinal Centers Determine Plasma Cell Output via Swiprosin-1/EFhd2. Cell Rep 2021; 32:108030. [PMID: 32783949 DOI: 10.1016/j.celrep.2020.108030] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 04/15/2020] [Accepted: 07/22/2020] [Indexed: 12/20/2022] Open
Abstract
Plasma cells secreting affinity-matured antibodies develop in germinal centers (GCs), where B cells migrate persistently and directionally over defined periods of time. How modes of GC B cell migration influence plasma cell development remained unclear. Through genetic deletion of the F-actin bundling protein Swiprosin-1/EF-hand domain family member 2 (EFhd2) and by two-photon microscopy, we show that EFhd2 restrains B cell speed in GCs and hapten-specific plasma cell output. Modeling the GC reaction reveals that increasing GC B cell speed promotes plasma cell generation. Lack of EFhd2 also reduces contacts of GC B cells with follicular dendritic cells in vivo. Computational modeling uncovers that both GC output and antibody affinity depend quantitatively on contacts of GC B cells with follicular dendritic cells when B cells migrate more persistently. Collectively, our data explain how GC B cells integrate speed and persistence of cell migration with B cell receptor affinity.
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Affiliation(s)
- Dorothea Reimer
- Division of Molecular Immunology, Universitätsklinikum Erlangen, Nikolaus-Fiebiger-Zentrum, FAU Erlangen-Nürnberg, Erlangen, Germany
| | - Michael Meyer-Hermann
- Department of Systems Immunology and Braunschweig, Integrated Centre of Systems Biology, Helmholtz Center for Infection Research, Braunschweig, Germany
| | | | - Tobit Steinmetz
- Division of Molecular Immunology, Universitätsklinikum Erlangen, Nikolaus-Fiebiger-Zentrum, FAU Erlangen-Nürnberg, Erlangen, Germany
| | - Philipp Tripal
- Optical Imaging Center (OICE), Universitätsklinikum Erlangen, FAU Erlangen-Nürnberg, Erlangen, Germany
| | - Jana Thomas
- Division of Molecular Immunology, Universitätsklinikum Erlangen, Nikolaus-Fiebiger-Zentrum, FAU Erlangen-Nürnberg, Erlangen, Germany
| | - Martin Boettcher
- Department of Internal Medicine V, Universitätsklinikum Erlangen, FAU Erlangen-Nürnberg, Erlangen, Germany
| | - Dimitrios Mougiakakos
- Department of Internal Medicine V, Universitätsklinikum Erlangen, FAU Erlangen-Nürnberg, Erlangen, Germany
| | - Sebastian R Schulz
- Division of Molecular Immunology, Universitätsklinikum Erlangen, Nikolaus-Fiebiger-Zentrum, FAU Erlangen-Nürnberg, Erlangen, Germany
| | - Sophia Urbanczyk
- Division of Molecular Immunology, Universitätsklinikum Erlangen, Nikolaus-Fiebiger-Zentrum, FAU Erlangen-Nürnberg, Erlangen, Germany
| | - Anja E Hauser
- Deutsches Rheumaforschungszentrum (DRFZ), Berlin, Germany; Charité - University Medicine, Berlin, Germany
| | - Raluca A Niesner
- Deutsches Rheumaforschungszentrum (DRFZ), Berlin, Germany; Dynamic and Functional In Vivo Imaging, Veterinary Medicine, Freie Universität, Berlin, Germany
| | - Dirk Mielenz
- Division of Molecular Immunology, Universitätsklinikum Erlangen, Nikolaus-Fiebiger-Zentrum, FAU Erlangen-Nürnberg, Erlangen, Germany.
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7
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Skóra MN, Pattij T, Beroun A, Kogias G, Mielenz D, de Vries T, Radwanska K, Müller CP. Personality driven alcohol and drug abuse: New mechanisms revealed. Neurosci Biobehav Rev 2020; 116:64-73. [PMID: 32565173 DOI: 10.1016/j.neubiorev.2020.06.023] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 05/15/2020] [Accepted: 06/16/2020] [Indexed: 12/15/2022]
Abstract
While the majority of the regular consumers of alcohol controls their consumption well over life span and even takes instrumentalization benefits from it, a minority, but yet high total number of users develops an alcohol addiction. It has long been known that particular personality types are more addiction prone than others. Here we review recent progress in the understanding of neurobiological pathways that determine personality and facilitate drug abuse. Novel approaches to characterize personality traits leading to addiction proneness in social settings in mice are discussed. A common genetic and neurobiological base for the behavioural traits of sensation seeking or a depressed phenotype and escalating alcohol consumption are reviewed. Furthermore, recent progress on how social and cognitive factors, including impulsivity and decision making, act at brain level to make an individual more vulnerable to alcohol abuse, are discussed. Altogether, this review provides an update on brain mechanisms underlying a broad spectrum of personality traits that make an individual more prone to alcohol and drug abuse and addiction.
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Affiliation(s)
- Maria Nalberczak Skóra
- Laboratory of Molecular Basis of Behavior, Nencki Institute, ul. L. Pasteura 3, Warsaw 02-093, Poland
| | - Tommy Pattij
- Department of Anatomy and Neurosciences, Amsterdam Neuroscience, Amsterdam University Medical Centers, Location VU University Medical Center, Amsterdam, the Netherlands
| | - Anna Beroun
- BRAINCITY, Nencki Institute, Warsaw 02-093, Poland
| | - Georgios Kogias
- Department of Psychiatry and Psychotherapy, Friedrich-Alexander University Erlangen-Nürnberg, Schwabachanlage 6, 91054 Erlangen, Germany
| | - Dirk Mielenz
- Division of Molecular Immunology, Department of Internal Medicine III, Nikolaus-Fiebiger-Center, University Clinic, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Taco de Vries
- Department of Anatomy and Neurosciences, Amsterdam Neuroscience, Amsterdam University Medical Centers, Location VU University Medical Center, Amsterdam, the Netherlands; Department of Molecular and Cellular Neuroscience, CNCR, VU University, Amsterdam, The Netherlands
| | - Kasia Radwanska
- Laboratory of Molecular Basis of Behavior, Nencki Institute, ul. L. Pasteura 3, Warsaw 02-093, Poland
| | - Christian P Müller
- Department of Psychiatry and Psychotherapy, Friedrich-Alexander University Erlangen-Nürnberg, Schwabachanlage 6, 91054 Erlangen, Germany.
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8
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Kogias G, Zheng F, Kalinichenko LS, Kornhuber J, Alzheimer C, Mielenz D, Müller CP. Swiprosin1/EFhd2 is involved in the monoaminergic and locomotor responses of psychostimulant drugs. J Neurochem 2020; 154:424-440. [DOI: 10.1111/jnc.14959] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 01/08/2020] [Accepted: 01/10/2020] [Indexed: 12/13/2022]
Affiliation(s)
- Georgios Kogias
- Department of Psychiatry and Psychotherapy Friedrich‐Alexander University Erlangen‐Nürnberg Erlangen Germany
| | - Fang Zheng
- Institute of Physiology and Pathophysiology Friedrich‐Alexander University Erlangen‐Nürnberg Erlangen Germany
| | - Liubov S. Kalinichenko
- Department of Psychiatry and Psychotherapy Friedrich‐Alexander University Erlangen‐Nürnberg Erlangen Germany
| | - Johannes Kornhuber
- Department of Psychiatry and Psychotherapy Friedrich‐Alexander University Erlangen‐Nürnberg Erlangen Germany
| | - Christian Alzheimer
- Institute of Physiology and Pathophysiology Friedrich‐Alexander University Erlangen‐Nürnberg Erlangen Germany
| | - Dirk Mielenz
- Division of Molecular Immunology Department of Internal Medicine III Nikolaus‐Fiebiger‐Center University Clinic Friedrich‐Alexander University Erlangen‐Nürnberg Erlangen Germany
| | - Christian P. Müller
- Department of Psychiatry and Psychotherapy Friedrich‐Alexander University Erlangen‐Nürnberg Erlangen Germany
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9
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Phospholipase C-Gamma 2 Activity in Familial Steroid-Sensitive Nephrotic Syndrome. Pediatr Res 2019; 85:719-723. [PMID: 30568185 DOI: 10.1038/s41390-018-0259-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 11/21/2018] [Accepted: 11/28/2018] [Indexed: 11/08/2022]
Abstract
BACKGROUND Familial Steroid-sensitive Nephrotic Syndrome (SSNS) is rare, complicating the identification of candidate genes. A recent population-based approach study of SSNS identified HLA-DQA1 and Phospholipase C-Gamma 2 (PLCG2) missense coding variants as candidate loci. PLCG2 is a signaling molecule regulated by phosphorylation and is critical for Ca2+ flux in cells of the immune system. METHODS In order to detect a candidate gene for familial SSNS, we conducted an whole-exome sequencing in a pedigree consisting of two healthy parents, two non-identical twin brothers with SSNS, and a healthy young sibling. Flow cytometric assays were conducted to investigate the effects of the identified PLCG2 rare variants on B cell receptor-mediated PLCG2 tyrosine 759 phosphorylation, as well as on Ca2+ flux. RESULTS Two missense rare variants in the PLCG2 gene were detected in the affected twins. An increase in tyrosine phosphorylation of PLCG2 as well as more rapid Ca2+ flux were noted in response to stimulation in the affected twins compared to their parents. CONCLUSIONS Rare variants in PLCG2 segregated with disease in familial SSNS. Functional studies suggest the combined rare variants result in a gain of function in PLCG2 activity. Taken together, these results support PLCG2 as a possible candidate locus for familial SSNS.
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Fürnrohr BG, Mielenz D. Quantification of Human Swiprosin-1/EFhd2 Expression on Protein and RNA Level. Methods Mol Biol 2019; 1929:595-605. [PMID: 30710299 DOI: 10.1007/978-1-4939-9030-6_37] [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: 12/30/2022]
Abstract
Many Ca2+-binding proteins are differentially regulated under pro-inflammatory conditions in different organs. Specific quantification of RNA and protein expression of those proteins demands validated protocols. Peripheral blood mononuclear cells (PBMC) can mirror an inflammatory status originating from several organs and can therefore be an important diagnostic tool. Swiprosin-1/EFhd2 (EFhd2) is a ~30 kDa Ca2+ and F-actin binding, cytoskeletal protein with two central EF hands and a C-terminal coiled-coil domain. Unbiased gene expression analyses and proteomics revealed that EFhd2 is regulated under pro-inflammatory conditions in several cell types and tissues. Here we describe validated protocols to quantify the expression of the human orthologue of Swiprosin-1/EFhd2 on RNA and protein level in PBMC. Both methods reveal that EFhd2 is stronger expressed in monocytes than in B cells of healthy donors. Thus, initial experiments relying on qPCR are likely to provide results with functional relevance. The higher expression of EFhd2 in monocytes could be related to monocyte migration under inflammatory conditions.
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Affiliation(s)
- Barbara G Fürnrohr
- Division of Molecular immunology, Department of Internal Medicine III, Nikolaus-Fiebiger-Center, University of Erlangen-Nürnberg, Erlangen, Germany
| | - Dirk Mielenz
- Division of Molecular immunology, Department of Internal Medicine III, Nikolaus-Fiebiger-Center, University of Erlangen-Nürnberg, Erlangen, Germany.
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11
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Conserved Noncoding Sequences Boost ADR1 and SP1 Regulated Human Swiprosin-1 Promoter Activity. Sci Rep 2018; 8:16481. [PMID: 30405162 PMCID: PMC6220333 DOI: 10.1038/s41598-018-34802-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 10/26/2018] [Indexed: 11/24/2022] Open
Abstract
Swiprosin-1 is expressed in various types of cells or tissues of different species. To investigate the mechanisms underlying Swiprosin-1 expression pattern, we analyzed the promoter activity of 2-kilobase genomic sequences located at 5′ flanking region of the Swiprosin-1 gene. The −2000/+41 bp of 5′ flanking untranslated promoter region of Swiprosin-1 gene was constitutively transactivated without significant effect of PMA, A23187, or PMA/A23187 stimulation in Jurkat T cells. Further, we identified 5′ deletant of proximal promoter region (−100/+41 to −70/+41) plays a pivotal role in activating the Swiprosin-1 gene in Jurkat T cells. Our studies also verified that ADR1 and Sp1 transcription factors were located between −70 and -100 locus of 5′ flanking proximal promoter region, which is critical for the Swiprosin-1 promoter activity. ADR1 and Sp1 were shown to bind the regions of −82, −79, −76, −73 and −70 and; −79, −78 and −77, respectively, within the proximal promoter region of Swiprosin-1. Finally conserved noncoding sequences (CNS) -1, -2 and -3 were located between the exon 1 and exon 2 of Swiprosin-1 gene and synergistically transactivated the Swiprosin-1 promoter. In summary, Swiprosin-1 was constitutively expressed in Jurkat T cells by the coordinate action of ADR1 and SP1 transcription factors at the transcriptional level and CNS further boost the proximal region of Swiprosin-1 promoter activity. Our findings provide novel insights that the transcriptional regulation of Swiprosin-1 by targeting ADR1 and Sp1 binding sites may be helpful in exploring novel therapeutic strategies for advanced immune or other disorders.
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12
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Peled M, Dragovich MA, Adam K, Strazza M, Tocheva AS, Vega IE, Mor A. EF Hand Domain Family Member D2 Is Required for T Cell Cytotoxicity. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2018; 201:2824-2831. [PMID: 30275048 PMCID: PMC6200634 DOI: 10.4049/jimmunol.1800839] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Accepted: 08/24/2018] [Indexed: 12/29/2022]
Abstract
Programmed cell death 1 (PD-1) is a major coinhibitory receptor and a member of the immunological synapse (IS). To uncover proteins that regulate PD-1 recruitment to the IS, we searched for cytoskeleton-related proteins that also interact with PD-1 using affinity purification mass spectrometry. Among these proteins, EF hand domain family member D2 (EFHD2), a calcium binding adaptor protein, was functionally and mechanistically analyzed for its contribution to PD-1 signaling. EFHD2 was required for PD-1 to inhibit cytokine secretion, proliferation, and adhesion of human T cells. Interestingly, EFHD2 was also required for human T cell-mediated cytotoxicity and for mounting an antitumor immune response in a syngeneic murine tumor model. Mechanistically, EFHD2 contributed to IS stability, lytic vesicles trafficking, and granzyme B secretion. Altogether, EFHD2 is an important regulator of T cell cytotoxicity and further studies should evaluate its role in T cell-mediated inflammation.
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Affiliation(s)
- Michael Peled
- Perlmutter Cancer Center, New York University School of Medicine, New York, NY 10016
- Pulmonary Department, The Chaim Sheba Medical Center, Ramat Gan 52620, Israel
| | - Matthew A Dragovich
- Perlmutter Cancer Center, New York University School of Medicine, New York, NY 10016
| | - Kieran Adam
- Perlmutter Cancer Center, New York University School of Medicine, New York, NY 10016
| | - Marianne Strazza
- Perlmutter Cancer Center, New York University School of Medicine, New York, NY 10016
| | - Anna S Tocheva
- Perlmutter Cancer Center, New York University School of Medicine, New York, NY 10016
| | - Irving E Vega
- Department of Translational Science and Molecular Medicine, College of Human Medicine, Michigan State University, Grand Rapids, MI 49503; and
| | - Adam Mor
- Perlmutter Cancer Center, New York University School of Medicine, New York, NY 10016;
- Columbia Center for Translational Immunology, Columbia University Medical Center, New York, NY 10032
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13
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Urbanczyk S, Stein M, Schuh W, Jäck HM, Mougiakakos D, Mielenz D. Regulation of Energy Metabolism during Early B Lymphocyte Development. Int J Mol Sci 2018; 19:E2192. [PMID: 30060475 PMCID: PMC6121686 DOI: 10.3390/ijms19082192] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Accepted: 07/25/2018] [Indexed: 01/03/2023] Open
Abstract
The most important feature of humoral immunity is the adaptation of the diversity of newly generated B cell receptors, that is, the antigen receptor repertoire, to the body's own and foreign structures. This includes the transient propagation of B progenitor cells and B cells, which possess receptors that are positively selected via anabolic signalling pathways under highly competitive conditions. The metabolic regulation of early B-cell development thus has important consequences for the expansion of normal or malignant pre-B cell clones. In addition, cellular senescence programs based on the expression of B cell identity factors, such as Pax5, act to prevent excessive proliferation and cellular deviation. Here, we review the basic mechanisms underlying the regulation of glycolysis and oxidative phosphorylation during early B cell development in bone marrow. We focus on the regulation of glycolysis and mitochondrial oxidative phosphorylation at the transition from non-transformed pro- to pre-B cells and discuss some ongoing issues. We introduce Swiprosin-2/EFhd1 as a potential regulator of glycolysis in pro-B cells that has also been linked to Ca2+-mediated mitoflashes. Mitoflashes are bioenergetic mitochondrial events that control mitochondrial metabolism and signalling in both healthy and disease states. We discuss how Ca2+ fluctuations in pro- and pre-B cells may translate into mitoflashes in early B cells and speculate about the consequences of these changes.
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Affiliation(s)
- Sophia Urbanczyk
- Division of Molecular Immunology, Nikolaus-Fiebiger-Center, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany.
| | - Merle Stein
- Department of Internal Medicine V, University Hospital, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany.
| | - Wolfgang Schuh
- Division of Molecular Immunology, Nikolaus-Fiebiger-Center, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany.
| | - Hans-Martin Jäck
- Division of Molecular Immunology, Nikolaus-Fiebiger-Center, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany.
| | - Dimitrios Mougiakakos
- Institute of Comparative Molecular Endocrinology (CME), University of Ulm, 89081 Ulm, Germany.
| | - Dirk Mielenz
- Division of Molecular Immunology, Nikolaus-Fiebiger-Center, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany.
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EFhd2/Swiprosin-1 is a common genetic determinator for sensation-seeking/low anxiety and alcohol addiction. Mol Psychiatry 2018; 23:1303-1319. [PMID: 28397836 PMCID: PMC5984092 DOI: 10.1038/mp.2017.63] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Revised: 02/03/2017] [Accepted: 02/10/2017] [Indexed: 12/19/2022]
Abstract
In many societies, the majority of adults regularly consume alcohol. However, only a small proportion develops alcohol addiction. Individuals at risk often show a high sensation-seeking/low-anxiety behavioural phenotype. Here we asked which role EF hand domain containing 2 (EFhd2; Swiprosin-1) plays in the control of alcohol addiction-associated behaviours. EFhd2 knockout (KO) mice drink more alcohol than controls and spontaneously escalate their consumption. This coincided with a sensation-seeking and low-anxiety phenotype. A reversal of the behavioural phenotype with β-carboline, an anxiogenic inverse benzodiazepine receptor agonist, normalized alcohol preference in EFhd2 KO mice, demonstrating an EFhd2-driven relationship between personality traits and alcohol preference. These findings were confirmed in a human sample where we observed a positive association of the EFhd2 single-nucleotide polymorphism rs112146896 with lifetime drinking and a negative association with anxiety in healthy adolescents. The lack of EFhd2 reduced extracellular dopamine levels in the brain, but enhanced responses to alcohol. In confirmation, gene expression analysis revealed reduced tyrosine hydroxylase expression and the regulation of genes involved in cortex development, Eomes and Pax6, in EFhd2 KO cortices. These findings were corroborated in Xenopus tadpoles by EFhd2 knockdown. Magnetic resonance imaging (MRI) in mice showed that a lack of EFhd2 reduces cortical volume in adults. Moreover, human MRI confirmed the negative association between lifetime alcohol drinking and superior frontal gyrus volume. We propose that EFhd2 is a conserved resilience factor against alcohol consumption and its escalation, working through Pax6/Eomes. Reduced EFhd2 function induces high-risk personality traits of sensation-seeking/low anxiety associated with enhanced alcohol consumption, which may be related to cortex function.
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15
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Regensburger M, Prots I, Reimer D, Brachs S, Loskarn S, Lie DC, Mielenz D, Winner B. Impact of Swiprosin-1/Efhd2 on Adult Hippocampal Neurogenesis. Stem Cell Reports 2018; 10:347-355. [PMID: 29337116 PMCID: PMC5830914 DOI: 10.1016/j.stemcr.2017.12.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2017] [Revised: 12/13/2017] [Accepted: 12/13/2017] [Indexed: 12/13/2022] Open
Abstract
Swiprosin-1/Efhd2 (Efhd2) is highly expressed in the CNS during development and in the adult. EFHD2 is regulated by Ca2+ binding, stabilizes F-actin, and promotes neurite extension. Previous studies indicated a dysregulation of EFHD2 in human Alzheimer's disease brains. We hypothesized a detrimental effect of genetic ablation of Efhd2 on hippocampal integrity and specifically investigated adult hippocampal neurogenesis. Efhd2 was expressed throughout adult neuronal development and in mature neurons. We observed a severe reduction of the survival of adult newborn neurons in Efhd2 knockouts, starting at the early neuroblast stage. Spine formation and dendrite growth of newborn neurons were compromised in full Efhd2 knockouts, but not upon cell-autonomous Efhd2 deletion. Together with our finding of severe hippocampal tauopathy in Efhd2 knockout mice, these data connect Efhd2 to impaired synaptic plasticity as present in Alzheimer's disease and identify a role of Efhd2 in neuronal survival and synaptic integration in the adult hippocampus. Efhd2 is expressed in the dentate gyrus and its loss reduces adult neurogenesis Reduced neurite complexity and spine density in new neurons of Efhd2 knockout mice Role of cell-extrinsic EFHD2 for dendrite morphology of adult newborn neurons Increased levels of pathological TAU in the hippocampus of Efhd2 knockout mice
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Affiliation(s)
- Martin Regensburger
- Department of Stem Cell Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Glueckstrasse 6, Erlangen 91054, Germany; Department of Neurology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen 91054, Germany; IZKF Junior Research Group III and BMBF Research Group Neuroscience, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen 91054, Germany
| | - Iryna Prots
- Department of Stem Cell Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Glueckstrasse 6, Erlangen 91054, Germany; IZKF Junior Research Group III and BMBF Research Group Neuroscience, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen 91054, Germany
| | - Dorothea Reimer
- Department of Molecular Immunology, Department of Internal Medicine III, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Glueckstrasse 6, Erlangen 91054, Germany
| | - Sebastian Brachs
- Department of Molecular Immunology, Department of Internal Medicine III, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Glueckstrasse 6, Erlangen 91054, Germany
| | - Sandra Loskarn
- Department of Stem Cell Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Glueckstrasse 6, Erlangen 91054, Germany; Department of Neurology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen 91054, Germany; IZKF Junior Research Group III and BMBF Research Group Neuroscience, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen 91054, Germany
| | - Dieter Chichung Lie
- Emil-Fischer Centre, Institute of Biochemistry, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen 91054, Germany
| | - Dirk Mielenz
- Department of Molecular Immunology, Department of Internal Medicine III, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Glueckstrasse 6, Erlangen 91054, Germany.
| | - Beate Winner
- Department of Stem Cell Biology, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Glueckstrasse 6, Erlangen 91054, Germany; IZKF Junior Research Group III and BMBF Research Group Neuroscience, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Erlangen 91054, Germany.
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Thylur RP, Gowda R, Mishra S, Jun CD. Swiprosin-1: Its Expression and Diverse Biological Functions. J Cell Biochem 2017; 119:150-156. [PMID: 28590012 DOI: 10.1002/jcb.26199] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2017] [Accepted: 06/06/2017] [Indexed: 02/02/2023]
Abstract
Swiprosin-1/EFhd2 is a Ca2+ binding adapter protein involved in the various cellular functions. Swiprosin-1 is significantly upregulated in a number of pathological conditions of inflammation, neurodegeneration, and cancer. Swiprosin-1 associated with actin and its expression level amplifies the production of proinflammatory mediators and modulates the activation of transcription factor during immune cells activation. This review aims at providing an overview of the expression and function of swiprosin-1/EFhd2 in various pathophysiological conditions. We also discussed the key role of swiprosin-1 in immune cell activation, cell migration, apoptosis, humoral immunity, cancer invasion and metastasis, neuronal transport, and major signaling cascades. J. Cell. Biochem. 119: 150-156, 2018. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Ramesh P Thylur
- School of Life Science, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-ro, Buk-gu, Gwangju, 61005, Republic of Korea
| | - Raghavendra Gowda
- Department of Pharmacology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Sumita Mishra
- Department of Pediatrics, Division of Medicine, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Chang-Duk Jun
- School of Life Science, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-ro, Buk-gu, Gwangju, 61005, Republic of Korea
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17
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Physiological and pathophysiological functions of Swiprosin-1/EFhd2 in the nervous system. Biochem J 2017; 473:2429-37. [PMID: 27515255 DOI: 10.1042/bcj20160168] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 05/03/2016] [Indexed: 12/15/2022]
Abstract
Synaptic dysfunction and dysregulation of Ca(2+) are linked to neurodegenerative processes and behavioural disorders. Our understanding of the causes and factors involved in behavioural disorders and neurodegeneration, especially Alzheimer's disease (AD), a tau-related disease, is on the one hand limited and on the other hand controversial. Here, we review recent data about the links between the Ca(2+)-binding EF-hand-containing cytoskeletal protein Swiprosin-1/EFhd2 and neurodegeneration. Specifically, we summarize the functional biochemical data obtained in vitro with the use of recombinant EFhd2 protein, and integrated them with in vivo data in order to interpret the emerging role of EFhd2 in synaptic plasticity and in the pathophysiology of neurodegenerative disorders, particularly involving the tauopathies. We also discuss its functions in actin remodelling through cofilin and small GTPases, thereby linking EFhd2, synapses and the actin cytoskeleton. Expression data and functional experiments in mice and in humans have led to the hypothesis that down-regulation of EFhd2, especially in the cortex, is involved in dementia.
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18
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Wang ZB, Han P, Tong LC, Luo Y, Su WH, Wei X, Yu XH, Liu WY, Zhang XH, Lei H, Li ZZ, Wang F, Chen JG, Ma TH, Su DF, Li L. Low level of swiprosin-1/EFhd2 in vestibular nuclei of spontaneously hypersensitive motion sickness mice. Sci Rep 2017; 7:40986. [PMID: 28128226 PMCID: PMC5269593 DOI: 10.1038/srep40986] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 12/14/2016] [Indexed: 11/13/2022] Open
Abstract
Susceptibility to motion sickness (MS) varies considerably among humans. However, the cause of such variation is unclear. Here, we used a classical genetic approach to obtain mouse strains highly sensitive and resistant to MS (SMS and RMS). Proteomics analysis revealed substantially lower swiprosin-1 expression in SMS mouse brains. Inducing MS via rotary stimulation decreased swiprosin-1 in the mouse brains. Swiprosin-1 knockout mice were much more sensitive to motion disturbance. Immunohistochemistry revealed strong swiprosin-1 expression in the vestibular nuclei (VN). Over-expressing swiprosin-1 in the VN of SMS mice decreased MS susceptibility. Down-regulating swiprosin-1 in the VN of RMS mice by RNAi increased MS susceptibility. Additional in vivo experiments revealed decreased swiprosin-1 expression by glutamate via the NMDA receptor. Glutamate increased neuronal excitability in SMS or swiprosin-1 knockout mice more prominently than in RMS or wild-type mice. These results indicate that swiprosin-1 in the VN is a critical determinant of the susceptibility to MS.
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Affiliation(s)
- Zhi-Bin Wang
- Department of Pharmacology, College of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Ping Han
- Department of Pharmacology, College of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Ling-Chang Tong
- Department of Pharmacology, College of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Yi Luo
- Department of Pharmacology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
| | - Wei-Heng Su
- Basal medical College, Dalian Medical University, Dalian, Liaoning 130041, China
| | - Xin Wei
- Department of Pharmacology, College of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Xu-Hong Yu
- Department of Pharmacology, College of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Wei-Ye Liu
- Department of Pharmacology, College of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Xiu-Hua Zhang
- Department of Pharmacology, College of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Hong Lei
- Department of Pharmacology, College of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Zhen-Zhen Li
- Department of Pharmacology, College of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Fang Wang
- Department of Pharmacology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
| | - Jian-Guo Chen
- Department of Pharmacology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China
| | - Tong-Hui Ma
- Basal medical College, Dalian Medical University, Dalian, Liaoning 130041, China
| | - Ding-Feng Su
- Department of Pharmacology, College of Pharmacy, Second Military Medical University, Shanghai 200433, China
| | - Ling Li
- Department of Pharmacology, College of Pharmacy, Second Military Medical University, Shanghai 200433, China
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Structural implications of Ca 2+-dependent actin-bundling function of human EFhd2/Swiprosin-1. Sci Rep 2016; 6:39095. [PMID: 27974828 PMCID: PMC5156911 DOI: 10.1038/srep39095] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Accepted: 11/17/2016] [Indexed: 01/20/2023] Open
Abstract
EFhd2/Swiprosin-1 is a cytoskeletal Ca2+-binding protein implicated in Ca2+-dependent cell spreading and migration in epithelial cells. EFhd2 domain architecture includes an N-terminal disordered region, a PxxP motif, two EF-hands, a ligand mimic helix and a C-terminal coiled-coil domain. We reported previously that EFhd2 displays F-actin bundling activity in the presence of Ca2+ and this activity depends on the coiled-coil domain and direct interaction of the EFhd2 core region. However, the molecular mechanism for the regulation of F-actin binding and bundling by EFhd2 is unknown. Here, the Ca2+-bound crystal structure of the EFhd2 core region is presented and structures of mutants defective for Ca2+-binding are also described. These structures and biochemical analyses reveal that the F-actin bundling activity of EFhd2 depends on the structural rigidity of F-actin binding sites conferred by binding of the EF-hands to Ca2+. In the absence of Ca2+, the EFhd2 core region exhibits local conformational flexibility around the EF-hand domain and C-terminal linker, which retains F-actin binding activity but loses the ability to bundle F-actin. In addition, we establish that dimerisation of EFhd2 via the C-terminal coiled-coil domain, which is necessary for F-actin bundling, occurs through the parallel coiled-coil interaction.
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20
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Comparison of Integrated Responses to Nonlethal and Lethal Hypothermal Stress in Milkfish (Chanos chanos): A Proteomics Study. PLoS One 2016; 11:e0163538. [PMID: 27657931 PMCID: PMC5033585 DOI: 10.1371/journal.pone.0163538] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2016] [Accepted: 09/10/2016] [Indexed: 11/19/2022] Open
Abstract
Milkfish is an important aquaculture species in Taiwan, and its high mortality during cold snaps in winter usually causes huge economic losses. To understand the effect of hypothermal stress and the corresponding compensatory stress response in milkfish, this study aimed to compare liver and gill protein levels between milkfish exposed to nonlethal (18°C), lethal (16°C), and control (28°C) temperatures. Using a proteomics approach based on two-dimensional electrophoresis and nano-LC-MS/MS analysis, this study identified thirty unique protein spots from milkfish livers and gills for which protein abundance was significantly different between nonlethal, lethal, and control temperature groups. Proteins identified in the liver were classified into three different categories according to their cellular function: (1) anti-oxidative stress, (2) apoptotic pathway, and (3) cytoskeleton. Similarly, proteins identified in the gill were sorted in five different functional categories: (1) cytoskeleton, (2) immune response, (3) protein quality control, (4) energy production, and (5) intracellular homeostasis. Based on functional information derived from the identified proteins, we assumed that different levels of hypothermal stress had a different effect and induced a different cellular response. Upon nonlethal hypothermal stress, the identified proteins were involved in anti-oxidative stress and anti-inflammation pathways, suggesting that milkfish had high levels of oxidative stress in the liver and exhibited inflammation response in the gill. Upon lethal hypothermal stress, however, identified proteins were associated with apoptosis in the liver and regulation of intracellular homeostasis in the gill. The present study provided evidence to illustrate different multi-physiological responses to nonlethal and lethal hypothermal stress in milkfish livers and gills.
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21
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Vega IE. EFhd2, a Protein Linked to Alzheimer's Disease and Other Neurological Disorders. Front Neurosci 2016; 10:150. [PMID: 27064956 PMCID: PMC4814571 DOI: 10.3389/fnins.2016.00150] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 03/21/2016] [Indexed: 01/20/2023] Open
Abstract
EFhd2 is a conserved calcium binding protein linked to different neurological disorders and types of cancer. Although, EFhd2 is more abundant in neurons, it is also found in other cell types. The physiological function of this novel protein is still unclear, but it has been shown in vitro to play a role in calcium signaling, apoptosis, actin cytoskeleton, and regulation of synapse formation. Recently, EFhd2 was shown to promote cell motility by modulating the activity of Rac1, Cdc42, and RhoA. Although, EFhd2's role in promoting cell invasion and metastasis is of great interest in cancer biology, this review focusses on the evidence that links EFhd2 to Alzheimer's disease (AD) and other neurological disorders. Altered expression of EFhd2 has been documented in AD, Parkinson's disease, Huntington's disease, Amyotrophic Lateral Sclerosis, and schizophrenia, indicating that Efhd2 gene expression is regulated in response to neuropathological processes. However, the specific role that EFhd2 plays in the pathophysiology of neurological disorders is still poorly understood. Recent studies demonstrated that EFhd2 has structural characteristics similar to amyloid proteins found in neurological disorders. Moreover, EFhd2 co-aggregates and interacts with known neuropathological proteins, such as tau, C9orf72, and Lrrk2. These results suggest that EFhd2 may play an important role in the pathophysiology of neurodegenerative diseases. Therefore, the understanding of EFhd2's role in health and disease could lead to decipher molecular mechanisms that become activated in response to neuronal stress and degeneration.
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Affiliation(s)
- Irving E Vega
- Department of Translational Science and Molecular Medicine, College of Human Medicine, Michigan State University Grand Rapids, MI, USA
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22
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The calcium-binding protein EFhd2 modulates synapse formation in vitro and is linked to human dementia. J Neuropathol Exp Neurol 2015; 73:1166-82. [PMID: 25383639 PMCID: PMC4238966 DOI: 10.1097/nen.0000000000000138] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
EFhd2 is a calcium-binding adaptor protein that has been found to be associated with pathologically aggregated tau in the brain in Alzheimer disease and in a mouse model of frontotemporal dementia. EFhd2 has cell type-specific functions, including the modulation of intracellular calcium responses, actin dynamics, and microtubule transport. Here we report that EFhd2 protein and mRNA levels are reduced in human frontal cortex tissue affected by different types of dementia with and without tau pathology. We show that EFhd2 is mainly a neuronal protein in the brain and is abundant in the forebrain. Using short hairpin RNA-mediated knockdown of EFhd2 expression in cultured cortical neurons, we demonstrate that loss of EFhd2 affects the number of synapses developed in vitro whereas it does not alter neurite outgrowth per se. Our data suggest that EFhd2 is involved in the control of synapse development and maintenance through means other than affecting neurite development. The changes in expression levels observed in human dementias might, therefore, play a significant role in disease onset and progression of dementia, which is characterized by the loss of synapses.
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The adaptor protein Swiprosin-1/EFhd2 is dispensable for platelet function in mice. PLoS One 2014; 9:e107139. [PMID: 25243606 PMCID: PMC4170979 DOI: 10.1371/journal.pone.0107139] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 08/06/2014] [Indexed: 11/19/2022] Open
Abstract
Background Platelets are anuclear cell fragments derived from bone marrow megakaryocytes that safeguard vascular integrity, but may also cause pathological vessel occlusion. Reorganizations of the platelet cytoskeleton and agonist-induced intracellular Ca2+-mobilization are crucial for platelet hemostatic function. EF-hand domain containing 2 (EFhd2, Swiprosin-1) is a Ca2+-binding cytoskeletal adaptor protein involved in actin remodeling in different cell types, but its function in platelets is unknown. Objective Based on the described functions of EFhd2 in immune cells, we tested the hypothesis that EFhd2 is a crucial adaptor protein for platelet function acting as a regulator of Ca2+-mobilization and cytoskeletal rearrangements. Methods and Results We generated EFhd2-deficient mice and analyzed their platelets in vitro and in vivo. Efhd2-/- mice displayed normal platelet count and size, exhibited an unaltered in vivo life span and showed normal Ca2+-mobilization and activation/aggregation responses to classic agonists. Interestingly, upon stimulation of the immunoreceptor tyrosine-based activation motif-coupled receptor glycoprotein (GP) VI, Efhd2-/- platelets showed a slightly increased coagulant activity. Furthermore, absence of EFhd2 had no significant impact on integrin-mediated clot retraction, actomyosin rearrangements and spreading of activated platelets on fibrinogen. In vivo EFhd2-deficiency resulted in unaltered hemostatic function and unaffected arterial thrombus formation. Conclusion These results show that EFhd2 is not essential for platelet function in mice indicating that other cytoskeletal adaptors may functionally compensate its loss.
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Brachs S, Turqueti-Neves A, Stein M, Reimer D, Brachvogel B, Bösl M, Winkler T, Voehringer D, Jäck HM, Mielenz D. Swiprosin-1/EFhd2 limits germinal center responses and humoral type 2 immunity. Eur J Immunol 2014; 44:3206-19. [PMID: 25092375 DOI: 10.1002/eji.201444479] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Revised: 06/27/2014] [Accepted: 07/31/2014] [Indexed: 01/19/2023]
Abstract
Activated B cells are selected for in germinal centers by regulation of their apoptosis. The Ca2+ -binding cytoskeletal adaptor protein Swiprosin-1/EFhd2 (EFhd2) can promote apoptosis in activated B cells. We therefore hypothesized that EFhd2 might limit humoral immunity by repressing both the germinal center reaction and the expected enhancement of immune responses in the absence of EFhd2. Here, we established EFhd2(-/-) mice on a C57BL/6 background, which revealed normal B- and T-cell development, basal Ab levels, and T-cell independent type 1, and T-cell independent type 2 responses. However, T cell-dependent immunization with sheep red blood cells and infection with the helminth Nippostrongylus brasiliensis (N.b) increased production of antibodies of multiple isotypes, as well as germinal center formation in EFhd2(-/-) mice. In addition, serum IgE levels and numbers of IgE+ plasma cells were strongly increased in EFhd2(-/-) mice, both after primary as well as after secondary N.b infection. Finally, mixed bone marrow chimeras unraveled an EFhd2-dependent B cell-intrinsic contribution to increased IgE plasma cell numbers in N.b-infected mice. Hence, we established a role for EFhd2 as a negative regulator of germinal center-dependent humoral type 2 immunity, with implications for the generation of IgE.
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Affiliation(s)
- Sebastian Brachs
- Division of Molecular Immunology, Department of Internal Medicine III, Nikolaus Fiebiger Center, Universitätsklinikum Erlangen and Friedrich-Alexander University Erlangen-Nuremberg, Nuremberg, Germany
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The Ca2+ sensor protein swiprosin-1/EFhd2 is present in neurites and involved in kinesin-mediated transport in neurons. PLoS One 2014; 9:e103976. [PMID: 25133820 PMCID: PMC4136728 DOI: 10.1371/journal.pone.0103976] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Accepted: 07/08/2014] [Indexed: 01/10/2023] Open
Abstract
Swiprosin-1/EFhd2 (EFhd2) is a cytoskeletal Ca2+ sensor protein strongly expressed in the brain. It has been shown to interact with mutant tau, which can promote neurodegeneration, but nothing is known about the physiological function of EFhd2 in the nervous system. To elucidate this question, we analyzed EFhd2−/−/lacZ reporter mice and showed that lacZ was strongly expressed in the cortex, the dentate gyrus, the CA1 and CA2 regions of the hippocampus, the thalamus, and the olfactory bulb. Immunohistochemistry and western blotting confirmed this pattern and revealed expression of EFhd2 during neuronal maturation. In cortical neurons, EFhd2 was detected in neurites marked by MAP2 and co-localized with pre- and post-synaptic markers. Approximately one third of EFhd2 associated with a biochemically isolated synaptosome preparation. There, EFhd2 was mostly confined to the cytosolic and plasma membrane fractions. Both synaptic endocytosis and exocytosis in primary hippocampal EFhd2−/− neurons were unaltered but transport of synaptophysin-GFP containing vesicles was enhanced in EFhd2−/− primary hippocampal neurons, and notably, EFhd2 inhibited kinesin mediated microtubule gliding. Therefore, we found that EFhd2 is a neuronal protein that interferes with kinesin-mediated transport.
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26
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Vázquez-Rosa E, Rodríguez-Cruz EN, Serrano S, Rodríguez-Laureano L, Vega IE. Cdk5 phosphorylation of EFhd2 at S74 affects its calcium binding activity. Protein Sci 2014; 23:1197-207. [PMID: 24917152 DOI: 10.1002/pro.2499] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 06/04/2014] [Accepted: 06/05/2014] [Indexed: 12/31/2022]
Abstract
EFhd2 is a calcium binding protein, which is highly expressed in the central nervous system and associated with pathological forms of tau proteins in tauopathies. Previous phosphoproteomics studies and bioinformatics analysis suggest that EFhd2 may be phosphorylated. Here, we determine whether Cdk5, a hyperactivated kinase in tauopathies, phosphorylates EFhd2 and influence its known molecular activities. The results indicated that EFhd2 is phosphorylated by brain extract of the transgenic mouse CK-p25, which overexpresses the Cdk5 constitutive activator p25. Consistently, in vitro kinase assays demonstrated that Cdk5, but not GSK3β, directly phosphorylates EFhd2. Biomass, tandem mass spectrometry, and mutagenesis analyses indicated that Cdk5 monophosphorylates EFhd2 at S74, but not the adjacent S76. Furthermore, Cdk5-mediated phosphorylation of EFhd2 affected its calcium binding activity. Finally, a phospho-specific antibody was generated against EFhd2 phosphorylated at S74 and was used to detect this phosphorylation event in postmortem brain tissue from Alzheimer's disease and normal-aging control cases. Results demonstrated that EFhd2 is phosphorylated in vivo at S74. These results imply that EFhd2's physiological and/or pathological function could be regulated by its phosphorylation state.
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Affiliation(s)
- Edwin Vázquez-Rosa
- Department of Chemistry, College of Natural Sciences, University of Puerto Rico-Río Piedras Campus, San Juan, Puerto Rico, 00931; Protein Mass Spectrometry Core Facility, College of Natural Sciences, University of Puerto Rico - Río Piedras Campus, San Juan, Puerto Rico, 00931
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27
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Brachs S, Lang C, Buslei R, Purohit P, Fürnrohr B, Kalbacher H, Jäck HM, Mielenz D. Monoclonal antibodies to discriminate the EF hand containing calcium binding adaptor proteins EFhd1 and EFhd2. Monoclon Antib Immunodiagn Immunother 2014; 32:237-45. [PMID: 23909416 DOI: 10.1089/mab.2013.0014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Small Ca(2+) binding adaptor proteins of the EF hand family play important roles in neuronal and immune cell Ca(2+) signaling. Swiprosin-1/EFhd2 (EFhd2) and Swiprosin-2/EFhd1 (EFhd1) are conserved and very homologous Ca(2+) binding adaptor proteins of the EF hand family, with possibly redundant functions. In particular, EFhd2 has been proposed to be involved in B cell signaling and neuropathological disorders. Little is known thus far about the expression of EFhd2 on the single cell level in tissue sections or blood cells. Here we describe the generation of four specific anti-EFhd2 monoclonal antibodies. These recognize murine and human EFhd2, but not murine EFhd1, and their binding site maps to a region in the N-terminal part of EFhd2, where EFhd2 and EFhd1 differ most. Moreover, to detect EFhd1 specifically, we also generated anti-EFhd1 polyclonal antibodies, making use of a singular peptide of the N-terminal part of the protein. Using anti-EFhd2 MAb, we reveal two EFhd2 pools in B cells, one at the membrane and one cytoplasmic pool. Staining of human peripheral blood mononuclear cells shows EFhd2 expression in B cells but a ∼5 fold higher expression in monocytes. Taken together, EFhd2 monoclonal antibodies will be valuable to assess the real subcellular localization and expression level of EFhd2 in healthy and diseased primary cells and tissues.
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Affiliation(s)
- Sebastian Brachs
- Division of Molecular Immunology, Department of Medicine III, University of Erlangen-Nürnberg, Nikolaus Fiebiger Center, Erlangen, Germany
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Kwon MS, Park KR, Kim YD, Na BR, Kim HR, Choi HJ, Piragyte I, Jeon H, Chung KH, Song WK, Eom SH, Jun CD. Swiprosin-1 is a novel actin bundling protein that regulates cell spreading and migration. PLoS One 2013; 8:e71626. [PMID: 23977092 PMCID: PMC3744483 DOI: 10.1371/journal.pone.0071626] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Accepted: 06/28/2013] [Indexed: 11/18/2022] Open
Abstract
Protein functions are often revealed by their localization to specialized cellular sites. Recent reports demonstrated that swiprosin-1 is found together with actin and actin-binding proteins in the cytoskeleton fraction of human mast cells and NK-like cells. However, direct evidence of whether swiprosin-1 regulates actin dynamics is currently lacking. We found that swiprosin-1 localizes to microvilli-like membrane protrusions and lamellipodia and exhibits actin-binding activity. Overexpression of swiprosin-1 enhanced lamellipodia formation and cell spreading. In contrast, swiprosin-1 knockdown showed reduced cell spreading and migration. Swiprosin-1 induced actin bundling in the presence of Ca(2+), and deletion of the EF-hand motifs partially reduced bundling activity. Swiprosin-1 dimerized in the presence of Ca(2+) via its coiled-coil domain, and a lysine (Lys)-rich region in the coiled-coil domain was essential for regulation of actin bundling. Consistent with these observations, mutations of the EF-hand motifs and coiled-coil region significantly reduced cell spreading and lamellipodia formation. We provide new evidence of how swiprosin-1 influences cytoskeleton reorganization and cell spreading.
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Affiliation(s)
- Min-Sung Kwon
- School of Life Sciences, Immune Synapse Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Gwangju, Korea
| | - Kyoung Ryoung Park
- School of Life Sciences, Immune Synapse Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Gwangju, Korea
| | - Young-Dae Kim
- School of Life Sciences, Immune Synapse Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Gwangju, Korea
| | - Bo-Ra Na
- School of Life Sciences, Immune Synapse Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Gwangju, Korea
| | - Hye-Ran Kim
- School of Life Sciences, Immune Synapse Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Gwangju, Korea
| | - Hak-Jong Choi
- School of Life Sciences, Immune Synapse Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Gwangju, Korea
| | - Indre Piragyte
- School of Life Sciences, Immune Synapse Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Gwangju, Korea
| | - Hyesung Jeon
- Biomedical Research Center, Korea Institute of Science and Technology, Seongbuk-gu, Seoul, Korea
| | - Kyung Hwun Chung
- School of Life Sciences, Immune Synapse Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Gwangju, Korea
| | - Woo Keun Song
- School of Life Sciences, Immune Synapse Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Gwangju, Korea
| | - Soo Hyun Eom
- School of Life Sciences, Immune Synapse Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Gwangju, Korea
| | - Chang-Duk Jun
- School of Life Sciences, Immune Synapse Research Center and Cell Dynamics Research Center, Gwangju Institute of Science and Technology, Gwangju, Korea
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Ferrer-Acosta Y, Rodríguez-Cruz EN, Orange F, De Jesús-Cortés H, Madera B, Vaquer-Alicea J, Ballester J, Guinel MJF, Bloom GS, Vega IE. EFhd2 is a novel amyloid protein associated with pathological tau in Alzheimer's disease. J Neurochem 2013; 125:921-31. [PMID: 23331044 PMCID: PMC3676478 DOI: 10.1111/jnc.12155] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2013] [Revised: 01/08/2013] [Accepted: 01/14/2013] [Indexed: 11/28/2022]
Abstract
EFhd2 is a conserved calcium-binding protein, abundant within the central nervous system. Previous studies identified EFhd2 associated with pathological forms of tau proteins in the tauopathy mouse model JNPL3, which expresses the human tau(P301L) mutant. This association was validated in human tauopathies, such as Alzheimer's disease (AD). However, the role that EFhd2 may play in tauopathies is still unknown. Here, we show that EFhd2 formed amyloid structures in vitro, a capability that is reduced by calcium ions. Electron microscopy (EM) analyses demonstrated that recombinant EFhd2 formed filamentous structures. EM analyses of sarkosyl-insoluble fractions derived from human AD brains also indicated that EFhd2 co-localizes with aggregated tau proteins and formed granular structures. Immunohistological analyses of brain slices demonstrated that EFhd2 co-localizes with pathological tau proteins in AD brains, confirming the co-aggregation of EFhd2 and pathological tau. Furthermore, EFhd2's coiled-coil domain mediated its self-oligomerization in vitro and its association with tau proteins in JNPL3 mouse brain extracts. The results demonstrate that EFhd2 is a novel amyloid protein associated with pathological tau proteins in AD brain and that calcium binding may regulate the formation of EFhd2's amyloid structures. Hence, EFhd2 may play an important role in the pathobiology of tau-mediated neurodegeneration.
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Affiliation(s)
- Yancy Ferrer-Acosta
- Department of Biology, College of Natural Sciences, University of Puerto Rico, PO Box 23360, San Juan, Puerto Rico 00931-3360, USA
| | - Eva N. Rodríguez-Cruz
- Department of Biology, College of Natural Sciences, University of Puerto Rico, PO Box 23360, San Juan, Puerto Rico 00931-3360, USA
| | - François Orange
- Nanoscopy Facility, College of Natural Sciences, University of Puerto Rico, PO Box 70377, San Juan, Puerto Rico 00936-8377, USA
- Department of Physics, College of Natural Sciences, University of Puerto Rico, PO Box 70377, San Juan, Puerto Rico 00936-8377, USA
| | - Hector De Jesús-Cortés
- Department of Biology, College of Natural Sciences, University of Puerto Rico, PO Box 23360, San Juan, Puerto Rico 00931-3360, USA
| | - Bismark Madera
- Department of Biology, College of Natural Sciences, University of Puerto Rico, PO Box 23360, San Juan, Puerto Rico 00931-3360, USA
- Confocal Microscopy Facility, College of Natural Sciences, University of Puerto Rico – Río Piedras Campus, San Juan, PR 00931
| | - Jaime Vaquer-Alicea
- Department of Biology, College of Natural Sciences, University of Puerto Rico, PO Box 23360, San Juan, Puerto Rico 00931-3360, USA
| | - Juan Ballester
- Department of Biology, College of Natural Sciences, University of Puerto Rico, PO Box 23360, San Juan, Puerto Rico 00931-3360, USA
| | - Maxime J-F. Guinel
- Nanoscopy Facility, College of Natural Sciences, University of Puerto Rico, PO Box 70377, San Juan, Puerto Rico 00936-8377, USA
- Department of Physics, College of Natural Sciences, University of Puerto Rico, PO Box 70377, San Juan, Puerto Rico 00936-8377, USA
- Department of Chemistry, College of Natural Sciences, University of Puerto Rico, PO Box 70377, San Juan, Puerto Rico 00936-8377, USA
| | - George S. Bloom
- Department of Biology, University of Virgina, Charlottesville, VA 22904, USA
| | - Irving E. Vega
- Department of Biology, College of Natural Sciences, University of Puerto Rico, PO Box 23360, San Juan, Puerto Rico 00931-3360, USA
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30
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Acosta YF, Rodríguez Cruz EN, Vaquer ADC, Vega IE. Functional and structural analysis of the conserved EFhd2 protein. Protein Pept Lett 2013; 20:573-83. [PMID: 22973849 PMCID: PMC3633529 DOI: 10.2174/0929866511320050011] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Revised: 08/25/2012] [Accepted: 08/26/2012] [Indexed: 01/14/2023]
Abstract
EFhd2 is a novel protein conserved from C. elegans to H. sapiens. This novel protein was originally identified in cells of the immune and central nervous systems. However, it is most abundant in the central nervous system, where it has been found associated with pathological forms of the microtubule-associated protein tau. The physiological or pathological roles of EFhd2 are poorly understood. In this study, a functional and structural analysis was carried to characterize the molecular requirements for EFhd2's calcium binding activity. The results showed that mutations of a conserved aspartate on either EF-hand motif disrupted the calcium binding activity, indicating that these motifs work in pair as a functional calcium binding domain. Furthermore, characterization of an identified single-nucleotide polymorphisms (SNP) that introduced a missense mutation indicates the importance of a conserved phenylalanine on EFhd2 calcium binding activity. Structural analysis revealed that EFhd2 is predominantly composed of alpha helix and random coil structures and that this novel protein is thermostable. EFhd2's thermo stability depends on its N-terminus. In the absence of the N-terminus, calcium binding restored EFhd2's thermal stability. Overall, these studies contribute to our understanding on EFhd2 functional and structural properties, and introduce it into the family of canonical EF-hand domain containing proteins.
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Affiliation(s)
- Yancy Ferrer Acosta
- Department of Biology, University of Puerto Rico-Río Piedras Campus, San Juan, PR 00931
| | - Eva N. Rodríguez Cruz
- Department of Biology, University of Puerto Rico-Río Piedras Campus, San Juan, PR 00931
| | - Ana del C. Vaquer
- Department of Biology, University of Puerto Rico-Río Piedras Campus, San Juan, PR 00931
| | - Irving E. Vega
- Department of Biology, University of Puerto Rico-Río Piedras Campus, San Juan, PR 00931
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