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Schulz D, Feulner L, Santos Rubenich D, Heimer S, Rohrmüller S, Reinders Y, Falchetti M, Wetzel M, Braganhol E, Lummertz da Rocha E, Schäfer N, Stöckl S, Brockhoff G, Wege AK, Fritsch J, Pohl F, Reichert TE, Ettl T, Bauer RJ. Subcellular localization of PD-L1 and cell-cycle-dependent expression of nuclear PD-L1 variants: implications for head and neck cancer cell functions and therapeutic efficacy. Mol Oncol 2024; 18:431-452. [PMID: 38103190 PMCID: PMC10850815 DOI: 10.1002/1878-0261.13567] [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: 08/08/2023] [Revised: 11/24/2023] [Accepted: 12/13/2023] [Indexed: 12/18/2023] Open
Abstract
The programmed cell death 1 ligand 1 (PD-L1)/programmed cell death protein 1 (PD-1) axis is primarily associated with immunosuppression in cytotoxic T lymphocytes (CTLs). However, mounting evidence is supporting the thesis that PD-L1 not only functions as a ligand but mediates additional cellular functions in tumor cells. Moreover, it has been demonstrated that PD-L1 is not exclusively localized at the cellular membrane. Subcellular fractionation revealed the presence of PD-L1 in various cellular compartments of six well-characterized head and neck cancer (HNC) cell lines, including the nucleus. Via Western blotting, we detected PD-L1 in its well-known glycosylated/deglycosylated state at 40-55 kDa. In addition, we detected previously unknown PD-L1 variants with a molecular weight at approximately 70 and > 150 kDa exclusively in nuclear protein fractions. These in vitro findings were confirmed with primary tumor samples from head and neck squamous cell carcinoma (HNSCC) patients. Furthermore, we demonstrated that nuclear PD-L1 variant expression is cell-cycle-dependent. Immunofluorescence staining of PD-L1 in different cell cycle phases of synchronized HNC cells supported these observations. Mechanisms of nuclear PD-L1 trafficking remain less understood; however, proximity ligation assays showed a cell-cycle-dependent interaction of the cytoskeletal protein vimentin with PD-L1, whereas vimentin could serve as a potential shuttle for nuclear PD-L1 transportation. Mass spectrometry after PD-L1 co-immunoprecipitation, followed by gene ontology analysis, indicated interaction of nuclear PD-L1 with proteins involved in DNA remodeling and messenger RNA (mRNA) splicing. Our results in HNC cells suggest a highly complex regulation of PD-L1 and multiple tumor cell-intrinsic functions, independent of immune regulation. These observations bear significant implications for the therapeutic efficacy of immune checkpoint inhibition.
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Affiliation(s)
- Daniela Schulz
- Department of Oral and Maxillofacial SurgeryUniversity Hospital RegensburgGermany
- Department of Oral and Maxillofacial Surgery, Experimental Oral and Maxillofacial Surgery, Center for Medical BiotechnologyUniversity Hospital RegensburgGermany
| | - Laura Feulner
- Department of Oral and Maxillofacial SurgeryUniversity Hospital RegensburgGermany
- Department of Oral and Maxillofacial Surgery, Experimental Oral and Maxillofacial Surgery, Center for Medical BiotechnologyUniversity Hospital RegensburgGermany
| | - Dominique Santos Rubenich
- Department of Oral and Maxillofacial SurgeryUniversity Hospital RegensburgGermany
- Department of Oral and Maxillofacial Surgery, Experimental Oral and Maxillofacial Surgery, Center for Medical BiotechnologyUniversity Hospital RegensburgGermany
- Postgraduation program in BiosciencesFederal University of Health Sciences from Porto AlegreBrazil
| | - Sina Heimer
- Department of Oral and Maxillofacial SurgeryUniversity Hospital RegensburgGermany
| | - Sophia Rohrmüller
- Department of Oral and Maxillofacial SurgeryUniversity Hospital RegensburgGermany
- Department of Oral and Maxillofacial Surgery, Experimental Oral and Maxillofacial Surgery, Center for Medical BiotechnologyUniversity Hospital RegensburgGermany
| | - Yvonne Reinders
- Leibniz‐Institute for Analytical Sciences, ISAS e.V.DortmundGermany
| | - Marcelo Falchetti
- Department of Microbiology, Immunology and ParasitologyFederal University of Santa CatarinaFlorianópolisBrazil
| | - Martin Wetzel
- Department of Oral and Maxillofacial Surgery, Experimental Oral and Maxillofacial Surgery, Center for Medical BiotechnologyUniversity Hospital RegensburgGermany
| | - Elizandra Braganhol
- Department of Basic Health SciencesFederal University of Health Sciences from Porto AlegreBrazil
| | - Edroaldo Lummertz da Rocha
- Department of Microbiology, Immunology and ParasitologyFederal University of Santa CatarinaFlorianópolisBrazil
| | - Nicole Schäfer
- Department of Orthopaedic Surgery, Experimental OrthopaedicsUniversity of RegensburgGermany
- Department of Orthopaedic Surgery, Experimental Orthopaedics, Center for Medical BiotechnologyUniversity Hospital RegensburgGermany
| | - Sabine Stöckl
- Department of Orthopaedic Surgery, Experimental OrthopaedicsUniversity of RegensburgGermany
- Department of Orthopaedic Surgery, Experimental Orthopaedics, Center for Medical BiotechnologyUniversity Hospital RegensburgGermany
| | - Gero Brockhoff
- Department of Gynecology and ObstetricsUniversity Medical Center RegensburgGermany
| | - Anja K. Wege
- Department of Gynecology and ObstetricsUniversity Medical Center RegensburgGermany
| | - Jürgen Fritsch
- Department of Infection Prevention and Infectious DiseasesUniversity Medical Center RegensburgGermany
| | - Fabian Pohl
- Department of RadiotherapyUniversity Medical Center RegensburgGermany
| | - Torsten E. Reichert
- Department of Oral and Maxillofacial SurgeryUniversity Hospital RegensburgGermany
| | - Tobias Ettl
- Department of Oral and Maxillofacial SurgeryUniversity Hospital RegensburgGermany
| | - Richard J. Bauer
- Department of Oral and Maxillofacial SurgeryUniversity Hospital RegensburgGermany
- Department of Oral and Maxillofacial Surgery, Experimental Oral and Maxillofacial Surgery, Center for Medical BiotechnologyUniversity Hospital RegensburgGermany
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Chen M, Ma Y, Chang W. SARS-CoV-2 and the Nucleus. Int J Biol Sci 2022; 18:4731-4743. [PMID: 35874947 PMCID: PMC9305274 DOI: 10.7150/ijbs.72482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 06/20/2022] [Indexed: 11/22/2022] Open
Abstract
The ongoing COVID-19 pandemic is caused by an RNA virus, SARS-CoV-2. The genome of SARS-CoV-2 lacks a nuclear phase in its life cycle and is replicated in the cytoplasm. However, interfering with nuclear trafficking using pharmacological inhibitors greatly reduces virus infection and virus replication of other coronaviruses is blocked in enucleated cells, suggesting a critical role of the nucleus in virus infection. Here, we summarize the alternations of nuclear pathways caused by SARS-CoV-2, including nuclear translocation pathways, innate immune responses, mRNA metabolism, epigenetic mechanisms, DNA damage response, cytoskeleton regulation, and nuclear rupture. We consider how these alternations contribute to virus replication and discuss therapeutic treatments that target these pathways, focusing on small molecule drugs that are being used in clinical studies.
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Affiliation(s)
- Mengqi Chen
- Department of Biomedical Sciences, Faculty of Health Sciences, University of Macau, Taipa, Macau, China
| | - Yue Ma
- Department of Biomedical Sciences, Faculty of Health Sciences, University of Macau, Taipa, Macau, China
| | - Wakam Chang
- Department of Biomedical Sciences, Faculty of Health Sciences, University of Macau, Taipa, Macau, China
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Bogorodskiy A, Okhrimenko I, Maslov I, Maliar N, Burkatovskii D, von Ameln F, Schulga A, Jakobs P, Altschmied J, Haendeler J, Katranidis A, Sorokin I, Mishin A, Gordeliy V, Büldt G, Voos W, Gensch T, Borshchevskiy V. Accessing Mitochondrial Protein Import in Living Cells by Protein Microinjection. Front Cell Dev Biol 2021; 9:698658. [PMID: 34307376 PMCID: PMC8292824 DOI: 10.3389/fcell.2021.698658] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 06/15/2021] [Indexed: 01/06/2023] Open
Abstract
Mitochondrial protein biogenesis relies almost exclusively on the expression of nuclear-encoded polypeptides. The current model postulates that most of these proteins have to be delivered to their final mitochondrial destination after their synthesis in the cytoplasm. However, the knowledge of this process remains limited due to the absence of proper experimental real-time approaches to study mitochondria in their native cellular environment. We developed a gentle microinjection procedure for fluorescent reporter proteins allowing a direct non-invasive study of protein transport in living cells. As a proof of principle, we visualized potential-dependent protein import into mitochondria inside intact cells in real-time. We validated that our approach does not distort mitochondrial morphology and preserves the endogenous expression system as well as mitochondrial protein translocation machinery. We observed that a release of nascent polypeptides chains from actively translating cellular ribosomes by puromycin strongly increased the import rate of the microinjected pre-protein. This suggests that a substantial amount of mitochondrial translocase complexes was involved in co-translational protein import of endogenously expressed pre-proteins. Our protein microinjection method opens new possibilities to study the role of mitochondrial protein import in cell models of various pathological conditions as well as aging processes.
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Affiliation(s)
- Andrey Bogorodskiy
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Ivan Okhrimenko
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Ivan Maslov
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Nina Maliar
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Dmitrii Burkatovskii
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Florian von Ameln
- Environmentally-Induced Cardiovascular Degeneration, Central Institute of Clinical Chemistry and Laboratory Medicine, Medical Faculty, University Hospital and Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
- IUF–Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany
| | - Alexey Schulga
- Molecular Immunology Laboratory, Shemyakin & Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Philipp Jakobs
- Environmentally-Induced Cardiovascular Degeneration, Central Institute of Clinical Chemistry and Laboratory Medicine, Medical Faculty, University Hospital and Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Joachim Altschmied
- Environmentally-Induced Cardiovascular Degeneration, Central Institute of Clinical Chemistry and Laboratory Medicine, Medical Faculty, University Hospital and Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
- IUF–Leibniz Research Institute for Environmental Medicine, Düsseldorf, Germany
| | - Judith Haendeler
- Environmentally-Induced Cardiovascular Degeneration, Central Institute of Clinical Chemistry and Laboratory Medicine, Medical Faculty, University Hospital and Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Alexandros Katranidis
- Institute of Biological Information Processing (IBI-6: Cellular Structural Biology), Forschungszentrum Jülich, Jülich, Germany
| | - Ivan Sorokin
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
- Institute of Protein Research, Russian Academy of Sciences, Pushchino, Russia
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia
| | - Alexey Mishin
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Valentin Gordeliy
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
- Institute of Biological Information Processing (IBI-7: Structural Biochemistry), Forschungszentrum Jülich, Jülich, Germany
- JuStruct: Jülich Center for Structural Biology, Forschungszentrum Jülich, Jülich, Germany
- Institut de Biologie Structurale (IBS), Université Grenoble Alpes, CEA, CNRS, Grenoble, France
| | - Georg Büldt
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Wolfgang Voos
- Institute of Biochemistry and Molecular Biology (IBMB), Faculty of Medicine, University of Bonn, Bonn, Germany
| | - Thomas Gensch
- Institute of Biological Information Processing (IBI-1: Molecular and Cellular Physiology), Forschungszentrum Jülich, Jülich, Germany
| | - Valentin Borshchevskiy
- Research Center for Molecular Mechanisms of Aging and Age-Related Diseases, Moscow Institute of Physics and Technology, Dolgoprudny, Russia
- Institute of Biological Information Processing (IBI-7: Structural Biochemistry), Forschungszentrum Jülich, Jülich, Germany
- JuStruct: Jülich Center for Structural Biology, Forschungszentrum Jülich, Jülich, Germany
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An H, Richardson A, Rajasekariah P, Zhong L, Fernando BSM, Macmillan A, Klotzsch E, Bryant K, Kaakoush NO, Tedla N. Nuclear Leukocyte Immunoglobulin-like Receptor A3 Is Monomeric and Is Involved in Multiple Layers of Regulated Gene Expression and Translation. J Proteome Res 2021; 20:3078-3089. [PMID: 33793249 DOI: 10.1021/acs.jproteome.0c00946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The leukocyte immunoglobulin-like receptor A3 (LILRA3) is a soluble protein primarily expressed by peripheral blood monocytes and is abundant in sera of healthy donors. Extracellular LILRA3 is anti-inflammatory and displays neuro-regenerative functions in vitro. However, its intracellular expression, distribution, and function(s) remain unknown. Using a combination of high-resolution confocal and super-resolution microscopy, we identified intracellular expression of native LILRA3 in the nucleus of peripheral blood monocytes and in vitro-derived macrophages. This unexpected nuclear localization of LILRA3 was confirmed in LILRA3-GFP-transfected HEK293T cells. Western blot of proteins fractionated from primary macrophages and the transfected HEK293T cells confirmed nuclear localization of the native and expressed LILRA3 proteins. Interestingly, most of the LILRA3 in the nucleus was in a monomeric form like the biologically active secreted protein, while that in the other cellular compartments was in mixed monomeric, dimeric, and oligomeric forms. The predominant presence of monomeric LILRA3 in the nucleus was independently corroborated in transfected live HEK293T cells using the number and molecular brightness (N&B) analysis method. Immunoprecipitation and mass spectrometric peptide sequencing studies revealed that nuclear LILRA3 co-immunoprecipitated with several nuclear proteins involved in host protein synthesis machinery via direct interactions to a key multifunctional RNA-binding protein, the Ewing sarcoma breakpoint region 1 protein (EWS) (data are available via ProteomeXchange with identifier PXD024602). The biological significance of the nuclear expression of LILRA3 and its interaction with these key proteins remain to be elucidated.
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Affiliation(s)
- Hongyan An
- Mechanisms of Diseases and Translational Research, School of Medical Sciences, Department of Pathology, UNSW, Sydney 2052, Australia
| | - Alexander Richardson
- Mechanisms of Diseases and Translational Research, School of Medical Sciences, Department of Pathology, UNSW, Sydney 2052, Australia
| | - Poornima Rajasekariah
- Mechanisms of Diseases and Translational Research, School of Medical Sciences, Department of Pathology, UNSW, Sydney 2052, Australia
| | - Ling Zhong
- Bioanalytical Mass Spectrometry Facility, Mark Wainwright Analytical Centre, UNSW, Sydney 2052, Australia
| | - Bentotage Samitha M Fernando
- Mechanisms of Diseases and Translational Research, School of Medical Sciences, Department of Pathology, UNSW, Sydney 2052, Australia
| | - Alexander Macmillan
- Biomedical Imaging Facility, Mark Wainwright Analytical Centre, UNSW, Sydney 2052, Australia
| | - Enrico Klotzsch
- Laboratory of Applied Mechanobiology, Department for Health Sciences and Technology, ETH Zürich, Zürich 8093, Switzerland.,Institute for Biology, Experimental Biophysics/Mechanobiology, Humboldt University of Berlin, Berlin 10115, German
| | - Katherine Bryant
- Mechanisms of Diseases and Translational Research, School of Medical Sciences, Department of Pathology, UNSW, Sydney 2052, Australia
| | - Nadeem O Kaakoush
- Mechanisms of Diseases and Translational Research, School of Medical Sciences, Department of Pathology, UNSW, Sydney 2052, Australia
| | - Nicodemus Tedla
- Mechanisms of Diseases and Translational Research, School of Medical Sciences, Department of Pathology, UNSW, Sydney 2052, Australia
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Yu J, Qin B, Moyer AM, Nowsheen S, Tu X, Dong H, Boughey JC, Goetz MP, Weinshilboum R, Lou Z, Wang L. Regulation of sister chromatid cohesion by nuclear PD-L1. Cell Res 2020; 30:590-601. [PMID: 32350394 PMCID: PMC7343880 DOI: 10.1038/s41422-020-0315-8] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 03/31/2020] [Indexed: 12/31/2022] Open
Abstract
Programmed death ligand-1 (PD-L1 or B7-H1) is well known for its role in immune checkpoint regulation, but its function inside the tumor cells has rarely been explored. Here we report that nuclear PD-L1 is important for cancer cell sister chromatid cohesion. We found that depletion of PD-L1 suppresses cancer cell proliferation, colony formation in vitro, and tumor growth in vivo in immune-deficient NSG mice independent of its role in immune checkpoint. Specifically, PD-L1 functions as a subunit of the cohesin complex, and its deficiency leads to formation of multinucleated cells and causes a defect in sister chromatid cohesion. Mechanistically, PD-L1 compensates for the loss of Sororin, whose expression is suppressed in cancer cells overexpressing PD-L1. PD-L1 competes with Wing Apart-Like (WAPL) for binding to PDS5B, and secures proper sister chromatid cohesion and segregation. Our findings suggest an important role for nuclear PD-L1 in cancer cells independent of its function in immune checkpoint.
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Affiliation(s)
- Jia Yu
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, 55905, USA
| | - Bo Qin
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, 55905, USA
- Department of Oncology, Mayo Clinic, Rochester, MN, 55905, USA
| | - Ann M Moyer
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, 55905, USA
| | - Somaira Nowsheen
- Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic School of Medicine and the Mayo Clinic Medical Scientist Training Program, Mayo Clinic, Rochester, MN, 55905, USA
| | - Xinyi Tu
- Department of Oncology, Mayo Clinic, Rochester, MN, 55905, USA
| | - Haidong Dong
- Departments of Urology and Immunology, Mayo Clinic, Rochester, MN, 55905, USA
| | - Judy C Boughey
- Department of Surgery, Mayo Clinic, Rochester, MN, 55905, USA
| | - Matthew P Goetz
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, 55905, USA
- Department of Oncology, Mayo Clinic, Rochester, MN, 55905, USA
| | - Richard Weinshilboum
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, 55905, USA
| | - Zhenkun Lou
- Department of Oncology, Mayo Clinic, Rochester, MN, 55905, USA.
| | - Liewei Wang
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, 55905, USA.
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Montgomery MR, Hull EE. Alterations in the glycome after HDAC inhibition impact oncogenic potential in epigenetically plastic SW13 cells. BMC Cancer 2019; 19:79. [PMID: 30651077 PMCID: PMC6335691 DOI: 10.1186/s12885-018-5129-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Accepted: 11/23/2018] [Indexed: 02/07/2023] Open
Abstract
Background Defects in the type and degree of cellular glycosylation impact oncogenesis on multiple levels. Although the type of glycosylation is determined by protein sequence encoded by the genome, the extent and modifications of glycosylation depends on the activity of biosynthetic enzymes and recent data suggests that the glycome is also subject to epigenetic regulation. This study focuses on the ability of HDAC inhibition to alter glycosylation and to lead to pro-oncogenic alterations in the glycome as assessed by metastatic potential and chemoresistance. Methods Epigenetically plastic SW13 adrenocortical carcinoma cells were treated with FK228, an HDAC inhibitor with high affinity for HDAC1 and, to a lesser extent, HDAC2. In comparing HDAC inhibitor treated and control cells, differential expression of glycome-related genes were assessed by microarray. Differential glycosylation was then assessed by lectin binding arrays and the ability of cellular proteins to bind to glycans was assessed by glycan binding arrays. Differential sensitivity to paclitaxel, proliferation, and MMP activity were also assessed. Results Treatment with FK228 alters expression of enzymes in the biosynthetic pathways for a large number of glycome related genes including enzymes in all major glycosylation pathways and several glycan binding proteins. 84% of these differentially expressed glycome-related genes are linked to cancer, some as prognostic markers and others contributing basic oncogenic functions such as metastasis or chemoresistance. Glycan binding proteins also appear to be differentially expressed as protein extracts from treated and untreated cells show differential binding to glycan arrays. The impact of differential mRNA expression of glycosylation enzymes was documented by differential lectin binding. However, the assessment of changes in the glycome is complicated by the fact that detection of differential glycosylation through lectin binding is dependent on the methods used to prepare samples as protein-rich lysates show different binding than fixed cells in several cases. Paralleling the alterations in the glycome, treatment of SW13 cells with FK228 increases metastatic potential and reduces sensitivity to paclitaxel. Conclusions The glycome is substantially altered by HDAC inhibition and these changes may have far-reaching impacts on oncogenesis. Electronic supplementary material The online version of this article (10.1186/s12885-018-5129-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- McKale R Montgomery
- College of Human Sciences, Oklahoma State University, Stillwater, OK, 74078, USA
| | - Elizabeth E Hull
- Biomedical Sciences Program, College of Graduate Studies, Midwestern University, Glendale, AZ, 85308, USA.
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The Role of Stress-Induced O-GlcNAc Protein Modification in the Regulation of Membrane Transport. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2017; 2017:1308692. [PMID: 29456783 PMCID: PMC5804373 DOI: 10.1155/2017/1308692] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 12/03/2017] [Indexed: 02/06/2023]
Abstract
O-linked N-acetylglucosamine (O-GlcNAc) is a posttranslational modification that is increasingly recognized as a signal transduction mechanism. Unlike other glycans, O-GlcNAc is a highly dynamic and reversible process that involves the addition and removal of a single N-acetylglucosamine molecule to Ser/Thr residues of proteins. UDP-GlcNAc—the direct substrate for O-GlcNAc modification—is controlled by the rate of cellular metabolism, and thus O-GlcNAc is dependent on substrate availability. Serving as a feedback mechanism, O-GlcNAc influences the regulation of insulin signaling and glucose transport. Besides nutrient sensing, O-GlcNAc was also implicated in the regulation of various physiological and pathophysiological processes. Due to improvements of mass spectrometry techniques, more than one thousand proteins were detected to carry the O-GlcNAc moiety; many of them are known to participate in the regulation of metabolites, ions, or protein transport across biological membranes. Recent studies also indicated that O-GlcNAc is involved in stress adaptation; overwhelming evidences suggest that O-GlcNAc levels increase upon stress. O-GlcNAc elevation is generally considered to be beneficial during stress, although the exact nature of its protective effect is not understood. In this review, we summarize the current data regarding the oxidative stress-related changes of O-GlcNAc levels and discuss the implications related to membrane trafficking.
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Gurzawska K, Dirscherl K, Jørgensen B, Berglundh T, Jørgensen NR, Gotfredsen K. Pectin nanocoating of titanium implant surfaces - an experimental study in rabbits. Clin Oral Implants Res 2016; 28:298-307. [DOI: 10.1111/clr.12798] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/24/2016] [Indexed: 12/16/2022]
Affiliation(s)
- Katarzyna Gurzawska
- Institute of Odontology; Faculty of Health and Medical Sciences; University of Copenhagen; Copenhagen N Denmark
| | | | - Bodil Jørgensen
- Department of Plant and Environmental Sciences; Faculty of Life Sciences; University of Copenhagen; Frederiksberg C Denmark
| | - Tord Berglundh
- Department of Periodontolgy; Institute of Odontology; The Sahlgrenska Academy at University of Gothenburg; Gothenburg Sweden
- Institute of Clinical Medicine; Faculty of Health and Medical Sciences; University of Copenhagen; Copenhagen N Denmark
| | - Niklas Rye Jørgensen
- Research Center for Ageing and Osteoporosis; Departments of Diagnostics and Medicine and Clinical Biochemistry; Copenhagen University Hospital Glostrup; Glostrup Denmark
| | - Klaus Gotfredsen
- Institute of Odontology; Faculty of Health and Medical Sciences; University of Copenhagen; Copenhagen N Denmark
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9
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Reissmann S. Cell penetration: scope and limitations by the application of cell-penetrating peptides. J Pept Sci 2014; 20:760-84. [DOI: 10.1002/psc.2672] [Citation(s) in RCA: 176] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Revised: 06/06/2014] [Accepted: 06/10/2014] [Indexed: 12/23/2022]
Affiliation(s)
- Siegmund Reissmann
- Friedrich Schiller University, Biological and Pharmaceutical Faculty; Institute of Biochemistry and Biophysics; Dornburger Strasse 25 07743 Jena Germany
- Jena Bioscience GmbH; Loebstedter Strasse 80 07749 Jena Germany
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10
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Wiederschain GY. Glycobiology: progress, problems, and perspectives. BIOCHEMISTRY (MOSCOW) 2014; 78:679-96. [PMID: 24010832 DOI: 10.1134/s0006297913070018] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This review highlights different aspects of glycobiology with analysis of recent progress in the study of biosynthesis, degradation, and biological role of glycoconjugates and of hereditary diseases related to the metabolism of these compounds. In addition, the review presents some analysis of the papers of other authors who have contributed to this special issue.
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Affiliation(s)
- G Ya Wiederschain
- Program in Glycobiology, Department of Biology, Boston College, Chestnut Hill, MA 02467, USA.
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11
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Akita H, Ishii S, Miura N, Shaheen SM, Hayashi Y, Nakamura T, Kaji N, Baba Y, Harashima H. A DNA microarray-based analysis of immune-stimulatory and transcriptional responses of dendritic cells to KALA-modified nanoparticles. Biomaterials 2013; 34:8979-90. [DOI: 10.1016/j.biomaterials.2013.08.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Accepted: 08/01/2013] [Indexed: 01/05/2023]
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12
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Presence of urotensin-II receptors at the cell nucleus: Specific tissue distribution and hypoxia-induced modulation. Int J Biochem Cell Biol 2012; 44:639-47. [DOI: 10.1016/j.biocel.2011.12.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2011] [Revised: 12/14/2011] [Accepted: 12/27/2011] [Indexed: 02/07/2023]
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13
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Chatenet D, Nguyen TTM, Létourneau M, Fournier A. Update on the urotensinergic system: new trends in receptor localization, activation, and drug design. Front Endocrinol (Lausanne) 2012; 3:174. [PMID: 23293631 PMCID: PMC3533682 DOI: 10.3389/fendo.2012.00174] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Accepted: 12/10/2012] [Indexed: 12/17/2022] Open
Abstract
The urotensinergic system plays central roles in the physiological regulation of major mammalian organ systems, including the cardiovascular system. As a matter of fact, this system has been linked to numerous pathophysiological states including atherosclerosis, heart failure, hypertension, diabetes as well as psychological, and neurological disorders. The delineation of the (patho)physiological roles of the urotensinergic system has been hampered by the absence of potent and selective antagonists for the urotensin II-receptor (UT). Thus, a more precise definition of the molecular functioning of the urotensinergic system, in normal conditions as well as in a pathological state is still critically needed. The recent discovery of nuclear UT within cardiomyocytes has highlighted the cellular complexity of this system and suggested that UT-associated biological responses are not only initiated at the cell surface but may result from the integration of extracellular and intracellular signaling pathways. Thus, such nuclear-localized receptors, regulating distinct signaling pathways, may represent new therapeutic targets. With the recent observation that urotensin II (UII) and urotensin II-related peptide (URP) exert different biological effects and the postulate that they could also have distinct pathophysiological roles in hypertension, it appears crucial to reassess the recognition process involving UII and URP with UT, and to push forward the development of new analogs of the UT system aimed at discriminating UII- and URP-mediated biological activities. The recent development of such compounds, i.e. urocontrin A and rUII(1-7), is certainly useful to decipher the specific roles of UII and URP in vitro and in vivo. Altogether, these studies, which provide important information regarding the pharmacology of the urotensinergic system and the conformational requirements for binding and activation, will ultimately lead to the development of potent and selective drugs.
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Affiliation(s)
- David Chatenet
- Laboratoire d'études moléculaires et pharmacologiques des peptides, INRS – Institut Armand-Frappier, Université du Québec, Ville de LavalQC, Canada
- Laboratoire International Associé Samuel de Champlain (INSERM/INRS-Université de Rouen)France
- *Correspondence: David Chatenet and Alain Fournier, Laboratoire d'études moléculaires et pharmacologiques des peptides, INRS – Institut Armand-Frappier, Université du Québec, 531 Boulevard des Prairies, Ville de Laval, QC H7V 1B7, Canada. e-mail: ;
| | - Thi-Tuyet M. Nguyen
- Laboratoire d'études moléculaires et pharmacologiques des peptides, INRS – Institut Armand-Frappier, Université du Québec, Ville de LavalQC, Canada
- Laboratoire International Associé Samuel de Champlain (INSERM/INRS-Université de Rouen)France
| | - Myriam Létourneau
- Laboratoire d'études moléculaires et pharmacologiques des peptides, INRS – Institut Armand-Frappier, Université du Québec, Ville de LavalQC, Canada
- Laboratoire International Associé Samuel de Champlain (INSERM/INRS-Université de Rouen)France
| | - Alain Fournier
- Laboratoire d'études moléculaires et pharmacologiques des peptides, INRS – Institut Armand-Frappier, Université du Québec, Ville de LavalQC, Canada
- Laboratoire International Associé Samuel de Champlain (INSERM/INRS-Université de Rouen)France
- *Correspondence: David Chatenet and Alain Fournier, Laboratoire d'études moléculaires et pharmacologiques des peptides, INRS – Institut Armand-Frappier, Université du Québec, 531 Boulevard des Prairies, Ville de Laval, QC H7V 1B7, Canada. e-mail: ;
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Sekiguchi S, Niikura K, Matsuo Y, Yoshimura SH, Ijiro K. Nuclear transport facilitated by the interaction between nuclear pores and carbohydrates. RSC Adv 2012. [DOI: 10.1039/c1ra00616a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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15
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Akita H, Masuda T, Nishio T, Niikura K, Ijiro K, Harashima H. Improving in Vivo Hepatic Transfection Activity by Controlling Intracellular Trafficking: The Function of GALA and Maltotriose. Mol Pharm 2011; 8:1436-42. [DOI: 10.1021/mp200189s] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Hidetaka Akita
- Faculty of Pharmaceutical Sciences, Hokkaido University, Kita 12 Nishi 6, Kita-Ku, Sapporo, Hokkaido, 060-0812 Japan
| | - Tomoya Masuda
- Faculty of Pharmaceutical Sciences, Hokkaido University, Kita 12 Nishi 6, Kita-Ku, Sapporo, Hokkaido, 060-0812 Japan
| | - Takashi Nishio
- Research Institute for Electronic Science, Hokkaido University, Kita 21 Nishi 10, Kita-Ku, Sapporo, Hokkaido, 001-0021, Japan
| | - Kenichi Niikura
- Research Institute for Electronic Science, Hokkaido University, Kita 21 Nishi 10, Kita-Ku, Sapporo, Hokkaido, 001-0021, Japan
| | - Kuniharu Ijiro
- Research Institute for Electronic Science, Hokkaido University, Kita 21 Nishi 10, Kita-Ku, Sapporo, Hokkaido, 001-0021, Japan
| | - Hideyoshi Harashima
- Faculty of Pharmaceutical Sciences, Hokkaido University, Kita 12 Nishi 6, Kita-Ku, Sapporo, Hokkaido, 060-0812 Japan
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Wang H, Tao T, Tang J, Mao YH, Li W, Peng J, Tan G, Zhou YP, Zhong JX, Tseng SCG, Kawakita T, Zhao YX, Liu ZG. Importin 13 serves as a potential marker for corneal epithelial progenitor cells. Stem Cells 2010; 27:2516-26. [PMID: 19593795 DOI: 10.1002/stem.174] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Importin13 (IPO13), the newest member of importin-beta family discovered recently, is a unique nucleus-cytoplasm bidirectional transport receptor protein. In this study, IPO13 expression in human corneal tissue, limbal epithelial primary explant and clonal culture was evaluated by immunostaining and reverse-transcription polymerase chain reasgon. IPO13 function was evaluated in the corneal epithelial culture treated with IPO13 inhibitor, or fetal bovine serum (FBS)-containing Dulbecco's modified Eagle's medium (DMEM) medium by colony-forming efficiency, clone growth capacity, MTT, immunostaining, and Western blotting assay. IPO13 protein was expressed mainly in nuclei of limbal epithelial basal cells, but not in the other cell layers of limbus and full thickness of corneal epithelia. IPO13 was expressed in the majority of epithelial cells in early-stage clones and in the margin of late-stage clones. IPO13 was positively expressed in mouse TKE2 progenitor cells cultured in keratinocyte serum-free defined medium, while it became negative in FBS-containing DMEM, which promoted TKE2 cell differentiation. In the presence of IPO13 inhibitor, IPO13 expression and the proliferative capacity decreased in human limbal epithelial clones and mouse TKE2 cells, which were accompanied with the cell differentiation. In conclusion, our findings demonstrate for the first time that IPO13 is uniquely expressed by human limbal basal epithelial cells, and plays an important role in maintaining the phenotype, high proliferative potential, and less differentiation of corneal epithelial progenitor cells, suggesting that IPO13 could serve as a novel potential marker for corneal epithelial progenitor cells.
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Affiliation(s)
- Hua Wang
- Eye Institute and Affiliated Xiamen Eye Center, Xiamen University, Xiamen, Fujian, China
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Antony PMA, Mäntele S, Mollenkopf P, Boy J, Kehlenbach RH, Riess O, Schmidt T. Identification and functional dissection of localization signals within ataxin-3. Neurobiol Dis 2009; 36:280-92. [DOI: 10.1016/j.nbd.2009.07.020] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2009] [Revised: 07/22/2009] [Accepted: 07/27/2009] [Indexed: 10/20/2022] Open
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Niikura K, Ijiro K, Sekiguchi S. Multivalent display of oligosaccharides on nanoparticles accelerates their nuclear import. TRENDS GLYCOSCI GLYC 2009. [DOI: 10.4052/tigg.21.335] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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20
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Niikura K, Sekiguchi S, Nishio T, Masuda T, Akita H, Matsuo Y, Kogure K, Harashima H, Ijiro K. Oligosaccharide-Mediated Nuclear Transport of Nanoparticles. Chembiochem 2008; 9:2623-7. [DOI: 10.1002/cbic.200800464] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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21
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Masuda T, Akita H, Nishio T, Niikura K, Kogure K, Ijiro K, Harashima H. Development of lipid particles targeted via sugar-lipid conjugates as novel nuclear gene delivery system. Biomaterials 2007; 29:709-23. [PMID: 18001828 DOI: 10.1016/j.biomaterials.2007.09.039] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2007] [Accepted: 09/28/2007] [Indexed: 11/27/2022]
Abstract
Efficient nuclear gene delivery is essential for successful gene therapy. This study developed a novel system that mimics the mechanism of nuclear entry of adenovirus (Ad) by means of a Multifunctional Envelope-type Nano Device (MEND). In this system, plasmid DNA (pDNA) was condensed with polycation, followed by encapsulation in a lipid membrane. To target MEND to the nuclear pore complex (NPC), sugar served as a NPC-mediated nuclear targeting device was modified on the surface of the lipid envelope. This was accomplished via synthesis of a sugar-cholesterol conjugate. After binding of the MEND to the NPC, the pDNA core was transferred into the nucleus in conjunction with a breakdown of the lipid envelope. Sugar-modified MEND showed higher transfection efficiency compared with unmodified MEND, in non-dividing and dividing cells. Confocal microscopy confirmed that nuclear transfer of pDNA was improved by sugar modification of MEND. Furthermore, destabilization of the lipid envelope significantly enhanced transfection activity: therefore, nuclear-delivery efficiency was closely related to lipid envelope stability. Moreover, quantitative evaluation of cellular uptake and nuclear transfer processes by real-time PCR confirmed that the surface sugars affected nuclear transfer, but not cellular uptake. In summary, a novel system for the nuclear delivery of pDNA was successfully developed by using a sugar-modified MEND and by optimizing the lipid envelope stability.
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Affiliation(s)
- Tomoya Masuda
- Faculty of Pharmaceutical Sciences, Hokkaido University, Kita 12 Nishi 6, Kita-Ku, Sapporo, Hokkaido 060-0812, Japan
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Mishra G, Das RH. Characterization of a eukaryotic type serine/threonine kinase in Spodoptera litura nucleopolyhedrovirus-I (SpltNPV-I). Virus Res 2007; 128:126-34. [PMID: 17553586 DOI: 10.1016/j.virusres.2007.04.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2007] [Revised: 04/16/2007] [Accepted: 04/17/2007] [Indexed: 10/23/2022]
Abstract
An open reading frame (ORF) of 819nt coding for a predicted protein of 272 amino acids was identified in the genome of Spodoptera litura nucleopolyhedrovirus (SpltNPV-I). Sequence derived amino acid sequence analysis of this ORF suggested it to be a eukaryotic type protein kinase having conserved I-XI subdomains of Hanks kinase. In addition to kinase catalytic domains, this hypothetical protein had two bromodomains which could play regulatory roles in transcription. The ORF was expressed as approximately 31 kDa apoprotein in E. coli and approximately 33 kDa glycoprotein in Sf9 cells, and was called SpltNPV-I pk1 or pk1. The protein was localized in the nuclei of infected cells of the SpltNPV-I permissive cell line, NIV-HA-197. The recombinant protein had autophosphorylation and substrate phosphorylation activities in presence of Mn(2+) or Mg(2+), and these activities were inhibited by staurosporine. Mutation of Lys-50 to Met but not Lys-44 to Gln abolished pk1 kinase activity. Kinetics of pk1 showed that the rate of phosphorylation of SpltNPV-I pk1>MBP>histone H1, and both MBP and histone H1 had the K(m)s of 3muM. Analysis of phosphorylated protein showed the phosphorylation of serine and threonine residues, but not tyrosine. All these results suggested that identified SpltNPV-I ORF codes for a serine/threonine kinase.
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Affiliation(s)
- Gourav Mishra
- Comparative Genomics Unit, Institute of Genomics and Integrative Biology (CSIR), Delhi University Campus, Mall Road, Delhi 110 007, India
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Arnoys EJ, Wang JL. Dual localization: proteins in extracellular and intracellular compartments. Acta Histochem 2007; 109:89-110. [PMID: 17257660 DOI: 10.1016/j.acthis.2006.10.002] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2006] [Revised: 10/01/2006] [Accepted: 10/09/2006] [Indexed: 12/24/2022]
Abstract
The goal of this article is to provide a comprehensive catalog of those proteins documented to exhibit dual localization, being found in both the extracellular compartment (cell surface and extracellular medium) as well as the intracellular compartment (cytosol and nucleus). A large subset of these proteins that show dual localization is found both in the nucleus and outside of cells. Proteins destined to be secreted out of the cell or to be expressed at the cell surface usually enter the endomembrane pathway on the basis of a signal sequence that targets them into the endoplasmic reticulum. Proteins destined for import into the nucleus, on the other hand, usually carry a nuclear localization signal. We have organized our catalog in terms of the presence and absence of these trafficking signals: (a) proteins that contain a signal sequence but no nuclear localization signal; (b) proteins that contain both a signal sequence as well as a nuclear localization signal; (c) proteins that contain a nuclear localization signal but lack a signal sequence; and (d) proteins containing neither a signal sequence nor a nuclear localization signal. Novel insights regarding the activities of several classes of proteins exhibiting dual localization can be derived when one targeting signal is experimentally abrogated. For example, the mitogenic activity of both fibroblasts growth factor-1 and schwannoma-derived growth factor clearly requires nuclear localization, independent of the activation of the receptor tyrosine kinase signaling pathway. In addition, there is a growing list of integral membrane receptors that undergo translocation to the nucleus, with bona fide nuclear localization signals and transcription activation activity. The information provided in this descriptive catalog will, hopefully, stimulate investigations into the pathways and mechanisms of transport between these compartments and the physiological significance of dual localization.
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Affiliation(s)
- Eric J Arnoys
- Department of Chemistry and Biochemistry, Calvin College, Grand Rapids, MI 49546, USA
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Shu Y, Rintala-Maki ND, Wall VE, Wang K, Goard CA, Langdon CE, Sutherland LC. The apoptosis modulator and tumour suppressor protein RBM5 is a phosphoprotein. Cell Biochem Funct 2007; 25:643-53. [PMID: 16927403 DOI: 10.1002/cbf.1366] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
RBM5/LUCA-15/H37 is a nuclear SR-related RNA binding protein with the ability to modulate both apoptosis and the cell cycle, and retard tumour formation. How RBM5 functions to carry out these, potentially interrelated, biological activities is unknown. Since reversible phosphorylation has been shown to play an important role in the regulation of SR protein function, apoptosis and cell cycle control, in an attempt to elucidate the underlying mechanisms regulating RBM5 function, the phosphorylation status of RBM5 was investigated. Whole cell lysate from growing cell cultures was treated with the broad phosphatase spectrum of CIP, resulting in a decrease in the molecular mass of RBM5. A similar decrease in molecular mass, of a subset of RBM5 proteins, was observed during growth factor deprivation, in a manner consistent with partial dephosphorylation of RBM5. Molecular mass increased upon growth factor addition, demonstrating that this apoptosis-associated alteration in molecular mass was a reversible process. Immunoprecipitation and mutagenesis experiments strongly suggested that phosphotyrosines are not present in RBM5 under normal growth conditions, and that serine 69 is phosphorylated, but not by Akt kinase. Taken together, these results suggest that reversible phosphorylation of RBM5 is a mechanism capable of regulating RBM5 participation in modulating apoptosis, and perhaps tumour suppression.
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Affiliation(s)
- Yanjun Shu
- Tumour Biology Group, Regional Cancer Program of the Hôpital régional de Sudbury Regional Hospital, Sudbury, Ontario, Canada
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Gobeil F, Fortier A, Zhu T, Bossolasco M, Leduc M, Grandbois M, Heveker N, Bkaily G, Chemtob S, Barbaz D. G-protein-coupled receptors signalling at the cell nucleus: an emerging paradigm. Can J Physiol Pharmacol 2006; 84:287-97. [PMID: 16902576 DOI: 10.1139/y05-127] [Citation(s) in RCA: 139] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
G-protein-coupled receptors (GPCRs) comprise a wide family of monomeric heptahelical glycoproteins that recognize a broad array of extracellular mediators including cationic amines, lipids, peptides, proteins, and sensory agents. Thus far, much attention has been given towards the comprehension of intracellular signaling mechanisms activated by cell membrane GPCRs, which convert extracellular hormonal stimuli into acute, non-genomic (e.g., hormone secretion, muscle contraction, and cell metabolism) and delayed, genomic biological responses (e.g., cell division, proliferation, and apoptosis). However, with respect to the latter response, there is compelling evidence for a novel intracrine mode of genomic regulation by GPCRs that implies either the endocytosis and nuclear translocation of peripheral-liganded GPCR and (or) the activation of nuclearly located GPCR by endogenously produced, nonsecreted ligands. A noteworthy example of the last scenario is given by heptahelical receptors that are activated by bioactive lipoids (e.g., PGE(2) and PAF), many of which may be formed from bilayer membranes including those of the nucleus. The experimental evidence for the nuclear localization and signalling of GPCRs will be reviewed. We will also discuss possible molecular mechanisms responsible for the atypical compartmentalization of GPCRs at the cell nucleus, along with their role in gene expression.
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Affiliation(s)
- Fernand Gobeil
- Department of Pharmacology, Faculty of Medicine, Université de Sherbrooke, Fleurimont, Canada.
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Grosse S, Thévenot G, Monsigny M, Fajac I. Which mechanism for nuclear import of plasmid DNA complexed with polyethylenimine derivatives? J Gene Med 2006; 8:845-51. [PMID: 16685744 DOI: 10.1002/jgm.915] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND To investigate the nuclear import mechanism of plasmid/polyethylenimine (PEI) derivative complexes and the putative nuclear targeting of therapeutic genes by the use of oligosaccharides, we have studied the nuclear import of plasmid DNA complexed either with PEI or with lactosylated PEI (Lac-PEI) in cystic fibrosis human airway epithelial cells ( summation operatorCFTE29o- cells). METHODS AND RESULTS Cells were synchronized by a double-thymidine block protocol and gene transfer efficiency was evaluated: Lac-PEI- and PEI-mediated gene transfer was greatly increased when cells have undergone mitosis during the course of transfection. However, both types of complexes were able to transfect some growth-arrested cells. When the nuclear import of plasmid/Lac-PEI or plasmid/unsubstituted PEI complexes was studied in digitonin-permeabilized cells, the nuclear uptake of both types of complexes did not follow the classic pathway of nuclear localization sequence (NLS)-containing proteins and lactose residues did not act as a nuclear localization signal. CONCLUSIONS Our results show that for complexes made with PEI derivatives, the major route for plasmid DNA nuclear entry is a passive nuclear importation during mitosis when the nuclear membrane temporarily breaks down. However, albeit to a lesser extent as that observed in dividing cells, a plasmid DNA importation also occurs in nondividing cells by a yet unknown mechanism.
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Affiliation(s)
- Stéphanie Grosse
- Université Paris-Descartes, Faculté de Médecine, AP-HP, Hôpital Cochin, EA 2511, Paris, France
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Schlummer S, Vetter R, Kuder N, Henkel A, Chen YX, Li YM, Kuhlmann J, Waldmann H. Influence of serine O-glycosylation or O-phosphorylation close to the vJun nuclear localisation sequence on nuclear import. Chembiochem 2006; 7:88-97. [PMID: 16345111 DOI: 10.1002/cbic.200500212] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Nuclear import triggered by the nuclear-localisation sequence (NLS) of the viral Jun (vJun) protein is mediated by phosphorylation of a serine close to the NLS. Since phosphorylation and glycosylation of serine residues are often in a reciprocal "yin-yang" relationship, we investigated whether glycosylation of this serine with O-linked N-acetylglucosamine (O-GlcNAc) would also regulate nuclear import via the vJun NLS. Peptides containing the vJun NLS with an adjacent O-phosphorylated, O-GlcNAc-functionalised or unmodified serine, and equipped with an N-terminal biotin or a 7-nitrobenz-2-oxa-1,3-diazolyl (NBD) fluorescent label, were synthesised on the solid phase by means of an Fmoc/Boc strategy and a Pd0-sensitive HYCRON linker. Fluorescence-polarisation measurements on the NBD-labelled peptides indicated that modification with phosphate or O-GlcNAc leads to a decrease in affinity to the import-mediating adapter protein, importin alpha, of about one order of magnitude compared to the unmodified NLS. Microinjection of biotinylated NLS peptide conjugated with fluorescently labelled avidin into NIH/3T3 and MDCK cells, revealed that avidin-unmodified-NLS peptide was rapidly imported into the nucleus. However, either phosphate or O-GlcNAc next to the NLS caused almost complete exclusion of the protein conjugate from nuclear import. These findings indicate that nuclear import by the vJun NLS might not be regulated by a "yin-yang" modification of an adjacent serine with phosphate or O-GlcNAc. Rather, negative regulation of binding between the polybasic NLS and importin by a negatively charged or a bulky, uncharged residue appears likely.
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Affiliation(s)
- Stefanie Schlummer
- Max-Planck-Institut für Molekulare Physiologie, Abteilung Chemische Biologie, Otto-Hahn-Strasse 11, 44227 Dortmund, Germany
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Guinez C, Morelle W, Michalski JC, Lefebvre T. O-GlcNAc glycosylation: a signal for the nuclear transport of cytosolic proteins? Int J Biochem Cell Biol 2005; 37:765-74. [PMID: 15694836 DOI: 10.1016/j.biocel.2004.12.001] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2004] [Indexed: 11/28/2022]
Abstract
Year 2004 marks the 20th anniversary of the discovery of O-linked N-acetylglucosamine (O-GlcNAc) by Gerald W. Hart. Despite interest for O-GlcNAc, the functions played by this single monosaccharide remain poorly understood, though numerous roles have been suggested, among which is the involvement of O-GlcNAc in the nuclear transport of cytosolic proteins. This idea was first sustained by studies on bovine serum albumin that showed that the protein could be actively carried to the nucleus when it was modified with sugars. In this paper, we will review data on this puzzling problem. We will first describe the well-established nuclear localisation signal (NLS)-dependent nuclear transport by presenting the different factors involved, and then, we will examine where and how O-GlcNAc could be involved in nuclear transport. Whereas it has been suggested that O-GlcNAc could interfere at two levels in the nuclear transport both by modifying proteins to be translocated to the nucleus and by modifying the nucleoporins of the nuclear pore complex, according to us, this second idea seems unlikely. Part of this study will also be dedicated to a relatively new concept in the nuclear transport: the role of the 70-kDa heat shock proteins (HSP70). The action of the chaperone in nuclear translocation was put forward 10 years ago, but new findings suggest that this mechanism could be linked to O-GlcNAc glycosylation.
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Affiliation(s)
- Céline Guinez
- Unité Mixte de Recherches 8576 du CNRS, Glycobiologie Structurale et Fonctionnelle, IFR 118, USTL, Bâtiment C9, 59655 Villeneuve d'Ascq, France
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La microscopie confocale et le pathologiste. Ann Pathol 2004. [DOI: 10.1016/s0242-6498(04)94040-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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