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Itell HL, Humes D, Baumgarten NE, Overbaugh J. Host cell glycosylation selects for infection with CCR5- versus CXCR4-tropic HIV-1. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.05.556399. [PMID: 37732222 PMCID: PMC10508750 DOI: 10.1101/2023.09.05.556399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/22/2023]
Abstract
HIV-1 infection involves a selection bottleneck that leads to transmission of one or a few HIV variants, which nearly always use CCR5 as the coreceptor (R5 viruses) for viral entry as opposed to CXCR4 (X4 viruses). The host properties that drive this selection are not well understood and may hold keys to factors that govern HIV susceptibility. In this report, we identified SLC35A2, a transporter of UDP-galactose, as a candidate X4-specific restriction factor in CRISPR-knockout screens in primary target CD4+ T cells. SLC35A2 inactivation in CD4+ T cells, which resulted in truncation of glycans due to the absence of galactose, not only increased X4 infection levels, but also consistently decreased infection levels of R5 HIV strains. Single cycle infections demonstrated that the effect is host cell dependent. SLC35A2 is expressed in CD4+ T cells at different tissue sites, with high levels in the genital tract - the site of most HIV infections. These data support a role for a host cell protein that regulates glycan structure on HIV infection, with enhanced R5 infection but reduced X4 infection associated with SLC35A2-mediated glycosylation. Host cell glycosylation may therefore contribute to R5 selection and host susceptibility during HIV transmission.
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Affiliation(s)
- Hannah L. Itell
- Molecular and Cellular Biology PhD Program, University of Washington, Seattle, WA, 98109, USA
- Division of Human Biology, Fred Hutchinson Cancer Center, Seattle, WA, 98109, USA
| | - Daryl Humes
- Division of Human Biology, Fred Hutchinson Cancer Center, Seattle, WA, 98109, USA
- Present address: Tr1X Inc, La Jolla, CA, 92037, USA
| | - Nell E. Baumgarten
- Division of Human Biology, Fred Hutchinson Cancer Center, Seattle, WA, 98109, USA
| | - Julie Overbaugh
- Division of Human Biology, Fred Hutchinson Cancer Center, Seattle, WA, 98109, USA
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2
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Bona A, Seifert M, Thünauer R, Zodel K, Frew IJ, Römer W, Walz G, Yakulov TA. MARVEL domain containing CMTM4 affects CXCR4 trafficking. Mol Biol Cell 2022; 33:ar116. [PMID: 36044337 PMCID: PMC9634968 DOI: 10.1091/mbc.e22-05-0152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The MARVEL proteins CMTM4 and CMTM6 control PD-L1, thereby influencing tumor immunity. We found that defective zebrafish cmtm4 slowed the development of the posterior lateral line (pLL) by altering the Cxcr4b gradient across the pLL primordium (pLLP). Analysis in mammalian cells uncovered that CMTM4 interacted with CXCR4, altering its glycosylation pattern, but did not affect internalization or degradation of CXCR4 in the absence of its ligand CXCL12. Synchronized release of CXCR4 from the endoplasmic reticulum revealed that CMTM4 slowed CXCR4 trafficking from the endoplasmic reticulum to the plasma membrane without affecting overall cell surface expression. Altered CXCR4 trafficking reduced ligand-induced CXCR4 degradation and affected AKT but not ERK1/2 activation. CMTM4 expression, in contrast to that of CXCR4, correlated with the survival of patients with renal cell cancer in the TCGA cohort. Furthermore, we observed that cmtm4 depletion promotes the separation of cells from the pLLP cell cluster in zebrafish embryos. Collectively, our findings indicate that CMTM4 exerts general roles in the biosynthetic pathway of cell surface molecules and seems to affect CXCR4-dependent cell migration.
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Affiliation(s)
- Alexandra Bona
- Renal Division and,Spemann Graduate School of Biology and Medicine (SGBM), University of Freiburg, 79104 Freiburg, Germany,*Address correspondence to: Alexandra Bona (); Toma A. Yakulov ()
| | | | - Roland Thünauer
- Technology Platform Light Microscopy and Image Analysis (TP MIA), Leibniz Institute for Experimental Virology (HPI), 20251 Hamburg, Germany,Advanced Light and Fluorescence Microscopy (ALFM) Facility, Centre for Structural Systems Biology (CSSB), 22607 Hamburg, Germany
| | - Kyra Zodel
- Department of Medicine I, Medical Center, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany
| | - Ian J. Frew
- Department of Medicine I, Medical Center, Faculty of Medicine, University of Freiburg, 79106 Freiburg, Germany,German Cancer Consortium (DKTK), Partner Site Freiburg, and German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany,Signalling Research Centres BIOSS and CIBSS
| | - Winfried Römer
- Signalling Research Centres BIOSS and CIBSS,Freiburg Institute for Advanced Studies (FRIAS), and,Faculty of Biology, Albert-Ludwigs-University Freiburg, 79104 Freiburg, Germany
| | - Gerd Walz
- Renal Division and,Signalling Research Centres BIOSS and CIBSS
| | - Toma A. Yakulov
- Renal Division and,*Address correspondence to: Alexandra Bona (); Toma A. Yakulov ()
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3
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Bondos SE, Dunker AK, Uversky VN. Intrinsically disordered proteins play diverse roles in cell signaling. Cell Commun Signal 2022; 20:20. [PMID: 35177069 PMCID: PMC8851865 DOI: 10.1186/s12964-022-00821-7] [Citation(s) in RCA: 56] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 12/11/2021] [Indexed: 11/29/2022] Open
Abstract
Abstract Signaling pathways allow cells to detect and respond to a wide variety of chemical (e.g. Ca2+ or chemokine proteins) and physical stimuli (e.g., sheer stress, light). Together, these pathways form an extensive communication network that regulates basic cell activities and coordinates the function of multiple cells or tissues. The process of cell signaling imposes many demands on the proteins that comprise these pathways, including the abilities to form active and inactive states, and to engage in multiple protein interactions. Furthermore, successful signaling often requires amplifying the signal, regulating or tuning the response to the signal, combining information sourced from multiple pathways, all while ensuring fidelity of the process. This sensitivity, adaptability, and tunability are possible, in part, due to the inclusion of intrinsically disordered regions in many proteins involved in cell signaling. The goal of this collection is to highlight the many roles of intrinsic disorder in cell signaling. Following an overview of resources that can be used to study intrinsically disordered proteins, this review highlights the critical role of intrinsically disordered proteins for signaling in widely diverse organisms (animals, plants, bacteria, fungi), in every category of cell signaling pathway (autocrine, juxtacrine, intracrine, paracrine, and endocrine) and at each stage (ligand, receptor, transducer, effector, terminator) in the cell signaling process. Thus, a cell signaling pathway cannot be fully described without understanding how intrinsically disordered protein regions contribute to its function. The ubiquitous presence of intrinsic disorder in different stages of diverse cell signaling pathways suggest that more mechanisms by which disorder modulates intra- and inter-cell signals remain to be discovered. Graphical abstract ![]()
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Affiliation(s)
- Sarah E Bondos
- Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, TX, 77843, USA.
| | - A Keith Dunker
- Center for Computational Biology and Bioinformatics, Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL, 33612, USA.,Institute for Biological Instrumentation of the Russian Academy of Sciences, Federal Research Center "Pushchino Scientific Center for Biological Research of the Russian Academy of Sciences", Pushchino, Moscow Region, Russia, 142290
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4
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Gutjahr JC, Crawford KS, Jensen DR, Naik P, Peterson FC, Samson GPB, Legler DF, Duchene J, Veldkamp CT, Rot A, Volkman BF. The dimeric form of CXCL12 binds to atypical chemokine receptor 1. Sci Signal 2021; 14:14/696/eabc9012. [PMID: 34404752 DOI: 10.1126/scisignal.abc9012] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The pleiotropic chemokine CXCL12 is involved in diverse physiological and pathophysiological processes, including embryogenesis, hematopoiesis, leukocyte migration, and tumor metastasis. It is known to engage the classical receptor CXCR4 and the atypical receptor ACKR3. Differential receptor engagement can transduce distinct cellular signals and effects as well as alter the amount of free, extracellular chemokine. CXCR4 binds both monomeric and the more commonly found dimeric forms of CXCL12, whereas ACKR3 binds monomeric forms. Here, we found that CXCL12 also bound to the atypical receptor ACKR1 (previously known as Duffy antigen/receptor for chemokines or DARC). In vitro nuclear magnetic resonance spectroscopy and isothermal titration calorimetry revealed that dimeric CXCL12 bound to the extracellular N terminus of ACKR1 with low nanomolar affinity, whereas the binding affinity of monomeric CXCL12 was orders of magnitude lower. In transfected MDCK cells and primary human Duffy-positive erythrocytes, a dimeric, but not a monomeric, construct of CXCL12 efficiently bound to and internalized with ACKR1. This interaction between CXCL12 and ACKR1 provides another layer of regulation of the multiple biological functions of CXCL12. The findings also raise the possibility that ACKR1 can bind other dimeric chemokines, thus potentially further expanding the role of ACKR1 in chemokine retention and presentation.
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Affiliation(s)
- Julia C Gutjahr
- Centre for Microvascular Research, William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London EC1M 6BQ, UK
| | - Kyler S Crawford
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Davin R Jensen
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Prachi Naik
- Centre for Microvascular Research, William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London EC1M 6BQ, UK
| | - Francis C Peterson
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Guerric P B Samson
- Biotechnology Institute Thurgau (BITg), University of Konstanz, 8280 Kreuzlingen, Switzerland
| | - Daniel F Legler
- Biotechnology Institute Thurgau (BITg), University of Konstanz, 8280 Kreuzlingen, Switzerland.,Theodor Kocher Institute, University of Bern, 3012 Bern, Switzerland
| | - Johan Duchene
- Institute for Cardiovascular Prevention, Ludwig-Maximilians University, 80336 Munich, Germany
| | | | - Antal Rot
- Centre for Microvascular Research, William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London EC1M 6BQ, UK. .,Institute for Cardiovascular Prevention, Ludwig-Maximilians University, 80336 Munich, Germany.,Centre for Inflammation and Therapeutic Innovation, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London EC1M 6BQ, UK
| | - Brian F Volkman
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
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Ugonotti J, Chatterjee S, Thaysen-Andersen M. Structural and functional diversity of neutrophil glycosylation in innate immunity and related disorders. Mol Aspects Med 2020; 79:100882. [PMID: 32847678 DOI: 10.1016/j.mam.2020.100882] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 07/14/2020] [Indexed: 12/11/2022]
Abstract
The granulated neutrophils are abundant innate immune cells that utilize bioactive glycoproteins packed in cytosolic granules to fight pathogenic infections, but the neutrophil glycobiology remains poorly understood. Facilitated by technological advances in glycoimmunology, systems glycobiology and glycoanalytics, a considerable body of literature reporting on novel aspects of neutrophil glycosylation has accumulated. Herein, we summarize the building knowledge of the structural and functional diversity displayed by N- and O-linked glycoproteins spatiotemporally expressed and sequentially brought-into-action across the diverse neutrophil life stages during bone marrow maturation, movements to, from and within the blood circulation and microbicidal processes at the inflammatory sites in peripheral tissues. It transpires that neutrophils abundantly decorate their granule glycoproteins including neutrophil elastase, myeloperoxidase and cathepsin G with peculiar glyco-signatures not commonly reported in other areas of human glycobiology such as hyper-truncated chitobiose core- and paucimannosidic-type N-glycans and monoantennary complex-type N-glycans. Sialyl Lewisx, Lewisx, poly-N-acetyllactosamine extensions and core 1-/2-type O-glycans are also common neutrophil glyco-signatures. Granule-specific glycosylation is another fascinating yet not fully understood feature of neutrophils. Recent literature suggests that unconventional biosynthetic pathways and functions underpin these prominent neutrophil-associated glyco-phenotypes. The impact of glycosylation on key neutrophil effector functions including extravasation, degranulation, phagocytosis and formation of neutrophil extracellular traps during normal physiological conditions and in innate immune-related diseases is discussed. We also highlight new technologies that are expected to further advance neutrophil glycobiology and briefly discuss the untapped diagnostic and therapeutic potential of neutrophil glycosylation that could open avenues to combat the increasingly prevalent innate immune disorders.
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Affiliation(s)
- Julian Ugonotti
- Department of Molecular Sciences, Macquarie University, Sydney, NSW, 2109, Australia; Biomolecular Discovery Research Centre, Macquarie University, Sydney, NSW, 2109, Australia
| | - Sayantani Chatterjee
- Department of Molecular Sciences, Macquarie University, Sydney, NSW, 2109, Australia; Biomolecular Discovery Research Centre, Macquarie University, Sydney, NSW, 2109, Australia
| | - Morten Thaysen-Andersen
- Department of Molecular Sciences, Macquarie University, Sydney, NSW, 2109, Australia; Biomolecular Discovery Research Centre, Macquarie University, Sydney, NSW, 2109, Australia.
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6
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Host-Virus Arms Races Drive Elevated Adaptive Evolution in Viral Receptors. J Virol 2020; 94:JVI.00684-20. [PMID: 32493827 DOI: 10.1128/jvi.00684-20] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 06/01/2020] [Indexed: 02/02/2023] Open
Abstract
Viral receptors are the cell surface proteins that are hijacked by viruses to initialize their infections. Viral receptors are subject to two conflicting directional forces, namely, negative selection due to functional constraints and positive selection due to host-virus arms races. It remains largely obscure whether negative pleiotropy limits the rate of adaptation in viral receptors. Here, we perform evolutionary analyses of 96 viral receptor genes in primates and find that 41 out of 96 viral receptors experienced adaptive evolution. Many positively selected residues in viral receptors are located at the virus-receptor interfaces. Compared with control proteins, viral receptors exhibit significantly elevated rate of adaptation. Further analyses of genetic polymorphisms in human populations reveal signals of positive selection and balancing selection for 53 and 5 viral receptors, respectively. Moreover, we find that 49 viral receptors experienced different selection pressures in different human populations, indicating that viruses represent an important driver of local adaptation in humans. Our findings suggest that diverse viruses, many of which have not been known to infect nonhuman primates, have maintained antagonistic associations with primates for millions of years, and the host-virus conflicts drive accelerated adaptive evolution in viral receptors.IMPORTANCE Viruses hijack cellular proteins, termed viral receptors, to assist their entry into host cells. While viral receptors experience negative selection to maintain their normal functions, they also undergo positive selection due to an everlasting evolutionary arms race between viruses and hosts. A complete picture on how viral receptors evolve under two conflicting forces is still lacking. In this study, we systematically analyzed the evolution of 96 viral receptors in primates and human populations. We found around half of viral receptors underwent adaptive evolution and exhibit significantly elevated rates of adaptation compared to control genes in primates. We also found signals of past natural selection for 58 viral receptors in human populations. Interestingly, 49 viral receptors experienced different selection pressures in different human populations, indicating that viruses represent an important driver of local adaptation in humans. Our results suggest that host-virus arms races drive accelerated adaptive evolution in viral receptors.
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7
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Gao W, Li S, Xu Q, Zhu D, Zhang Q, Luo K, Zhang W. Molecular characterization and expression analysis of Asian swamp eel (Monopterus albus) CXC chemokine receptor (CXCR) 1a, CXCR1b, CXCR2, CXCR3a, CXCR3b, and CXCR4 after bacteria and poly I:C challenge. FISH & SHELLFISH IMMUNOLOGY 2019; 84:572-586. [PMID: 30359750 DOI: 10.1016/j.fsi.2018.10.055] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 10/13/2018] [Accepted: 10/22/2018] [Indexed: 06/08/2023]
Abstract
The CXC chemokine receptors (CXCRs) play critical roles in innate and adaptive immune systems. In this study, six Asian swamp eel (Monopterus albus) CXCRs (MaCXCR1-4) were identified and their molecular characterization and expression patterns were analyzed. The open reading frames (ORFs) of MaCXCR1a, MaCXCR1b, MaCXCR2, MaCXCR3a, MaCXCR3b, and MaCXCR4 were 1074 bp (base pairs), 1080 bp, 1125 bp, 1146 bp, 1083 bp, and 1140 bp, and encoded proteins of 357 aa (amino acids), 359 aa, 374 aa, 381 aa, 360 aa, and 379 aa, respectively. All these CXCRs have seven conserved transmembrane domains and four cysteines (with the exception of MaCXCR3b). Multiple sequence alignment revealed that the MaCXCRs possess a typical G-protein receptor family 1 signature and a DRY motif. There are also one to four potential N-glycosylation sites in the extracellular regions of the MaCXCRs, mainly distributed in the N-terminus and extracellular hydrophilic loop (ECL) 2 region. Phylogenetic analysis demonstrated that the MaCXCRs were clustered together with homologous proteins from other fish. Taken together with the amino acid identity and similarity analysis, these results suggested that the MaCXCRs are conserved with other homologous genes, in which CXCR4 is more conserved than CXCR1-3. The MaCXCRs loci showed conserved synteny among teleost fish, and we found that human CXCR1 shares a common ancestor with fish CXCR1a. MaCXCRs were constitutively expressed in a wide range of tissues (especially in immune-related tissues) with different expression levels, suggesting that the MaCXCRs have different roles in un-stimulated tissues, and may play vital roles under normal conditions. MaCXCRs showed different fold changes in the spleen after Aeromonas veronii and polyinosinic-polycytidylic acid (poly I:C) challenge, which suggested that MaCXCR1a and MaCXCR3a have longer antiviral activities compared with their antibacterial functions, and that MaCXCR1b possesses stronger antiviral than antibacterial activity. MaCXCR4 may play vital roles during bacterial and viral infection; however, MaCXCR2 has relatively small effect in antibacterial and antiviral responses. The differential responses of these genes to bacteria and poly I:C implied the differences in the mechanisms of defense against viruses and bacteria.
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Affiliation(s)
- Weihua Gao
- Engineering Research Center of Ecology and Agricultural Use of Wetland (Ministry of Education), Yangtze University, Jingzhou, 434024, PR China; Guangxi Key Laboratory of Marine Biotechnology, Guangxi Institute of Oceanology, Beihai, 536006, PR China
| | - Shuai Li
- Engineering Research Center of Ecology and Agricultural Use of Wetland (Ministry of Education), Yangtze University, Jingzhou, 434024, PR China; Guangxi Key Laboratory of Marine Biotechnology, Guangxi Institute of Oceanology, Beihai, 536006, PR China
| | - Qiaoqing Xu
- Engineering Research Center of Ecology and Agricultural Use of Wetland (Ministry of Education), Yangtze University, Jingzhou, 434024, PR China
| | - Dashi Zhu
- Engineering Research Center of Ecology and Agricultural Use of Wetland (Ministry of Education), Yangtze University, Jingzhou, 434024, PR China
| | - Qin Zhang
- Guangxi Key Laboratory of Marine Biotechnology, Guangxi Institute of Oceanology, Beihai, 536006, PR China
| | - Kai Luo
- Engineering Research Center of Ecology and Agricultural Use of Wetland (Ministry of Education), Yangtze University, Jingzhou, 434024, PR China; The Key Laboratory of Mariculture (Education Ministry of China), Ocean University of China, 5 Yushan Road, Qingdao, Shandong, 266003, PR China.
| | - Wenbing Zhang
- Engineering Research Center of Ecology and Agricultural Use of Wetland (Ministry of Education), Yangtze University, Jingzhou, 434024, PR China; The Key Laboratory of Mariculture (Education Ministry of China), Ocean University of China, 5 Yushan Road, Qingdao, Shandong, 266003, PR China.
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8
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How post-translational modifications influence the biological activity of chemokines. Cytokine 2018; 109:29-51. [DOI: 10.1016/j.cyto.2018.02.026] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Revised: 02/27/2018] [Accepted: 02/28/2018] [Indexed: 12/17/2022]
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9
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Zhou J, Zhao S, Dunker AK. Intrinsically Disordered Proteins Link Alternative Splicing and Post-translational Modifications to Complex Cell Signaling and Regulation. J Mol Biol 2018; 430:2342-2359. [DOI: 10.1016/j.jmb.2018.03.028] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 03/25/2018] [Accepted: 03/27/2018] [Indexed: 10/24/2022]
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10
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Abstract
Glycans are essential for the maintenance of normal biological function, with alterations in glycan expression being a hallmark of cancer. Cancer stem cells (CSCs) are a subset of cells within a tumour capable of self-renewal, cellular differentiation and resistances to conventional therapies. As is the case with stem cells, marker proteins present on the cell surface are frequently used to identify and enrich CSCs, with the expression of these markers statistical correlating with the likelihood of cancer recurrence and overall patient survival. As such CSC markers are of high clinical relevance. The majority of markers currently used to identify CSC populations are glycoproteins, and although the diverse biological roles for many of these markers are known, the nature and function of the glycan moiety on these glycoproteins remains to be fully elucidated. This mini-review summarises our current knowledge regarding the types and extent of CSC marker glycosylation, and the various roles that these glycans play in CSC biology, including in mediating cell adhesion, metastasis, evading apoptosis, tear shear resistance, tumour growth, maintaining pluripotency, self-renewal, trafficking, maintaining stability, maintaining enzymatic activity and aiding epithelial mesenchymal transitioning. Given that CSCs markers have multiple diverse biological functions, and are potentially of significant diagnostic and therapeutic benefit the search for new markers that are uniquely expressed on CSCs is vital to selectively target/identify this subset of cancer cells. As such we have also outlined how high-throughput lectin microarrays can be used to successfully profile the glycosylation status of CSC and to identify glyco-markers unique to CSCs.
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11
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Stone MJ, Hayward JA, Huang C, E Huma Z, Sanchez J. Mechanisms of Regulation of the Chemokine-Receptor Network. Int J Mol Sci 2017; 18:E342. [PMID: 28178200 PMCID: PMC5343877 DOI: 10.3390/ijms18020342] [Citation(s) in RCA: 184] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 01/18/2017] [Accepted: 01/26/2017] [Indexed: 12/18/2022] Open
Abstract
The interactions of chemokines with their G protein-coupled receptors promote the migration of leukocytes during normal immune function and as a key aspect of the inflammatory response to tissue injury or infection. This review summarizes the major cellular and biochemical mechanisms by which the interactions of chemokines with chemokine receptors are regulated, including: selective and competitive binding interactions; genetic polymorphisms; mRNA splice variation; variation of expression, degradation and localization; down-regulation by atypical (decoy) receptors; interactions with cell-surface glycosaminoglycans; post-translational modifications; oligomerization; alternative signaling responses; and binding to natural or pharmacological inhibitors.
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Affiliation(s)
- Martin J Stone
- Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia.
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia.
| | - Jenni A Hayward
- Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia.
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia.
| | - Cheng Huang
- Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia.
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia.
| | - Zil E Huma
- Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia.
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia.
| | - Julie Sanchez
- Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia.
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC 3800, Australia.
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12
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Benredjem B, Girard M, Rhainds D, St-Onge G, Heveker N. Mutational Analysis of Atypical Chemokine Receptor 3 (ACKR3/CXCR7) Interaction with Its Chemokine Ligands CXCL11 and CXCL12. J Biol Chem 2016; 292:31-42. [PMID: 27875312 DOI: 10.1074/jbc.m116.762252] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2016] [Revised: 11/09/2016] [Indexed: 12/21/2022] Open
Abstract
Atypical chemokine receptors do not mediate chemotaxis or G protein signaling, but they recruit arrestin. They also efficiently scavenge their chemokine ligands, thereby contributing to gradient maintenance and termination. ACKR3, also known as CXCR7, binds and degrades the constitutive chemokine CXCL12, which also binds the canonical receptor CXCR4, and CXCL11, which also binds CXCR3. Here we report comprehensive mutational analysis of the ACKR3 interaction with its chemokine ligands, using 30 substitution mutants. Readouts are radioligand binding competition, arrestin recruitment, and chemokine scavenging. Our results suggest different binding modes for both chemokines. CXCL11 depends on the ACKR3 N terminus and some extracellular loop (ECL) positions for primary binding, ECL residues mediate secondary binding and arrestin recruitment potency. CXCL12 binding required key residues Asp-1794.60 and Asp-2756.58 (residue numbering follows the Ballesteros-Weinstein scheme), with no evident involvement of N-terminal residues, suggesting an uncommon mode of receptor engagement. Mutation of residues corresponding to CRS2 in CXCR4 (positions Ser-1032.63 and Gln-3017.39) increased CXCL11 binding, but reduced CXCL12 affinity. Mutant Q301E7.39 did not recruit arrestin. Mutant K118A3.26 in ECL1 showed moderate baseline arrestin recruitment with ablation of ligand-induced responses. Substitutions that affected CXCL11 binding also diminished scavenging. However, detection of reduced CXCL12 scavenging by mutants with impaired CXCL12 affinity required drastically reduced receptor expression levels, suggesting that scavenging pathways can be saturated and that CXCL12 binding exceeds scavenging at higher receptor expression levels. Arrestin recruitment did not correlate with scavenging; although Q301E7.39 degraded chemokines in the absence of arrestin, S103D2.63 had reduced CXCL11 scavenging despite intact arrestin responses.
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Affiliation(s)
- Besma Benredjem
- From the Department of Biochemistry and Molecular Medicine, University of Montreal, Montréal H3T 1J4, Canada and.,Research Centre, Saint-Justine Hospital, University of Montreal, Montréal H3T 1C5, Canada
| | - Mélanie Girard
- From the Department of Biochemistry and Molecular Medicine, University of Montreal, Montréal H3T 1J4, Canada and.,Research Centre, Saint-Justine Hospital, University of Montreal, Montréal H3T 1C5, Canada
| | - David Rhainds
- From the Department of Biochemistry and Molecular Medicine, University of Montreal, Montréal H3T 1J4, Canada and.,Research Centre, Saint-Justine Hospital, University of Montreal, Montréal H3T 1C5, Canada
| | - Geneviève St-Onge
- Research Centre, Saint-Justine Hospital, University of Montreal, Montréal H3T 1C5, Canada
| | - Nikolaus Heveker
- From the Department of Biochemistry and Molecular Medicine, University of Montreal, Montréal H3T 1J4, Canada and .,Research Centre, Saint-Justine Hospital, University of Montreal, Montréal H3T 1C5, Canada
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13
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Wei XM, Xu HF, Cheng XD, Bu N, Zhou HZ. Position 22 of the V3 loop is associated with HIV infectivity. Arch Virol 2016; 162:637-643. [PMID: 27815696 DOI: 10.1007/s00705-016-3138-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Accepted: 10/28/2016] [Indexed: 11/29/2022]
Abstract
Human immunodeficiency virus subtype 1B (HIV-1B) binds to the CD4 receptor and co-receptor CCR5 or CXCR4 to enter T lymphocytes. The amino acid sequence of the HIV envelope glycoprotein V3 region determines the co-receptor tropism, thereby influencing the infectivity of the virus. Our research group previously found that the amino acid at position 22 of the V3 region may affect the infectivity of the virus, and in this study, we tested this hypothesis. We constructed pseudoviruses by changing the amino acids at position 22 of the V3 region in CCR5-tropic and CXCR4-tropic viruses and tested their infectivity. When the amino acid at V3 position 22 was altered in the CCR5- and CXCR4-tropic viruses, their ability to infect cells decreased to 20.6% and 17.14%, respectively. Therefore, we propose that residue 22 in the V3 region of subtype HIV-1B significantly influences the infectivity of the virus.
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Affiliation(s)
- Xue-Mei Wei
- Department of Laboratory Diagnosis, the First Affiliated Hospital of Harbin Medical University, 23 Youzheng Street, Nangang District, Harbin, Heilongjiang, 150001, People's Republic of China
| | - Hua-Feng Xu
- Department of Laboratory Diagnosis, Heilongjiang Provincial Hospital, Harbin, Heilongjiang, 150081, People's Republic of China
| | - Xue-Di Cheng
- Department of Laboratory Diagnosis, the First Affiliated Hospital of Harbin Medical University, 23 Youzheng Street, Nangang District, Harbin, Heilongjiang, 150001, People's Republic of China
| | - Nan Bu
- Department of Digestive Medicine, Jiamusi Central Hospital, Jiamusi, Heilongjiang, 154002, People's Republic of China
| | - Hai-Zhou Zhou
- Department of Laboratory Diagnosis, the First Affiliated Hospital of Harbin Medical University, 23 Youzheng Street, Nangang District, Harbin, Heilongjiang, 150001, People's Republic of China.
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14
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Peng L, Damschroder MM, Cook KE, Wu H, Dall'Acqua WF. Molecular basis for the antagonistic activity of an anti-CXCR4 antibody. MAbs 2016; 8:163-75. [PMID: 26514996 PMCID: PMC4966504 DOI: 10.1080/19420862.2015.1113359] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Antagonistic antibodies targeting the G-protein C-X-C chemokine receptor 4 (CXCR4) hold promising therapeutic potential in various diseases. We report for the first time the detailed mechanism of action at a molecular level of a potent anti-CXCR4 antagonistic antibody (MEDI3185). We characterized the MEDI3185 paratope using alanine scanning on all 6 complementary-determining regions (CDRs). We also mapped its epitope using CXCR4 mutagenesis to assess the relative importance of the CXCR4 N-terminal peptide, extracellular loops (ECL) and ligand-binding pocket. We show that the interaction between MEDI3185 and CXCR4 is mediated mostly by CDR3H in MEDI3185 and ECL2 in CXCR4. The MEDI3185 epitope comprises the entire ECL2 sequence, lacks any so-called ‘hot-spot’ and is remarkably resistant to mutations. The structure of MEDI3185 variable domains was modeled, and suggested a β-strand/β-strand interaction between MEDI3185 CDR3H and CXCR4 ECL2, resulting in direct steric hindrance with CXCR4 ligand SDF-1. These findings may have important implications for designing antibody therapies against CXCR4.
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Affiliation(s)
- Li Peng
- a Department of Antibody Discovery and Protein Engineering ; MedImmune LLC; One MedImmune Way ; Gaithersburg , MD 20878 , USA
| | - Melissa M Damschroder
- a Department of Antibody Discovery and Protein Engineering ; MedImmune LLC; One MedImmune Way ; Gaithersburg , MD 20878 , USA
| | - Kimberly E Cook
- a Department of Antibody Discovery and Protein Engineering ; MedImmune LLC; One MedImmune Way ; Gaithersburg , MD 20878 , USA
| | - Herren Wu
- a Department of Antibody Discovery and Protein Engineering ; MedImmune LLC; One MedImmune Way ; Gaithersburg , MD 20878 , USA
| | - William F Dall'Acqua
- a Department of Antibody Discovery and Protein Engineering ; MedImmune LLC; One MedImmune Way ; Gaithersburg , MD 20878 , USA
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15
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Shen HS, Yin J, Leng F, Teng RF, Xu C, Xia XY, Pan XM. HIV coreceptor tropism determination and mutational pattern identification. Sci Rep 2016; 6:21280. [PMID: 26883082 PMCID: PMC4756667 DOI: 10.1038/srep21280] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 01/20/2016] [Indexed: 12/20/2022] Open
Abstract
In the early stages of infection, Human Immunodeficiency Virus Type 1 (HIV-1) generally selects CCR5 as the primary coreceptor for entering the host cell. As infection progresses, the virus evolves and may exhibit a coreceptor-switch to CXCR4. Accurate determination coreceptor usage and identification key mutational patterns associated tropism switch are essential for selection of appropriate therapies and understanding mechanism of coreceptor change. We developed a classifier composed of two coreceptor-specific weight matrices (CMs) based on a full-scale dataset. For this classifier, we found an AUC of 0.97, an accuracy of 95.21% and an MCC of 0.885 (sensitivity 92.92%; specificity 95.54%) in a ten-fold cross-validation, outperforming all other methods on an independent dataset (13% higher MCC value than geno2pheno and 15% higher MCC value than PSSM). A web server (http://spg.med.tsinghua.edu.cn/CM.html) based on our classifier was provided. Patterns of genetic mutations that occur along with coreceptor transitions were further identified based on the score of each sequence. Six pairs of one-AA mutational patterns and three pairs of two-AA mutational patterns were identified to associate with increasing propensity for X4 tropism. These mutational patterns offered new insights into the mechanism of coreceptor switch and aided in monitoring coreceptor switch.
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Affiliation(s)
- Hui-Shuang Shen
- The Key Laboratory of Bioinformatics, Ministry of Education, School of Life Sciences, Tsinghua University, China
| | - Jason Yin
- Department of Biostatistics, Saw Swee Hock School of Public Health, National University of Singapore, Singapore
| | - Fei Leng
- The Key Laboratory of Bioinformatics, Ministry of Education, School of Life Sciences, Tsinghua University, China
| | - Rui-Fang Teng
- The Key Laboratory of Bioinformatics, Ministry of Education, School of Life Sciences, Tsinghua University, China
| | - Chao Xu
- The Key Laboratory of Bioinformatics, Ministry of Education, School of Life Sciences, Tsinghua University, China
| | - Xia-Yu Xia
- The Key Laboratory of Bioinformatics, Ministry of Education, School of Life Sciences, Tsinghua University, China
| | - Xian-Ming Pan
- The Key Laboratory of Bioinformatics, Ministry of Education, School of Life Sciences, Tsinghua University, China
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16
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Sand LGL, Jochemsen AG, Beletkaia E, Schmidt T, Hogendoorn PCW, Szuhai K. Novel splice variants of CXCR4 identified by transcriptome sequencing. Biochem Biophys Res Commun 2015; 466:89-94. [PMID: 26321665 DOI: 10.1016/j.bbrc.2015.08.113] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 08/25/2015] [Indexed: 10/23/2022]
Abstract
Chemokine receptor CXCR4 is involved in tumor growth, angiogenesis and metastasis. Its function is regulated in many ways and one of them is alternative splicing. We identified two novel coding splice variants (CXCR4-3 and CXCR4-4) of CXCR4 in Ewing sarcoma (EWS) cell lines by whole transcriptome sequencing and validated these with reverse transcriptase- PCR and Sanger sequencing. The novel splice variants were expressed at RNA level in Ewing sarcoma samples and in other tumor cell lines and placenta, but not in lung. Due to inclusion of an additional exon the new isoforms have a 70 and 33 amino acid elongation of the N-terminal end of CXCR4. For validation at protein and functional level, the identified isoforms and normal CXCR4 were cloned into an EYFP tagged vector and ectopically expressed in HEK293T cell line and EWS cell line A673. Of the novel isoforms CXCR4-3 showed cell membrane localization and a functional response after addition of CXCR4 ligand CXCL12a. CXCR4-4 showed strong cytoplasmic accumulation and no response to ligand treatment. The role of the newly discovered isoforms in CXCR4 signaling is likely to be limited. Our data stresses the importance of functional validation of newly identified isoforms.
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Affiliation(s)
- L G L Sand
- Department of Pathology, Leiden University Medical Center, Leiden, The Netherlands
| | - A G Jochemsen
- Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, The Netherlands
| | - E Beletkaia
- Huygens-Kamerlingh Onnes Laboratory, Leiden Institute of Physics, Leiden University, Leiden, The Netherlands
| | - T Schmidt
- Huygens-Kamerlingh Onnes Laboratory, Leiden Institute of Physics, Leiden University, Leiden, The Netherlands
| | - P C W Hogendoorn
- Department of Pathology, Leiden University Medical Center, Leiden, The Netherlands
| | - K Szuhai
- Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, The Netherlands.
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17
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Sand LGL, Szuhai K, Hogendoorn PCW. Sequencing Overview of Ewing Sarcoma: A Journey across Genomic, Epigenomic and Transcriptomic Landscapes. Int J Mol Sci 2015; 16:16176-215. [PMID: 26193259 PMCID: PMC4519945 DOI: 10.3390/ijms160716176] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 07/03/2015] [Accepted: 07/07/2015] [Indexed: 12/17/2022] Open
Abstract
Ewing sarcoma is an aggressive neoplasm occurring predominantly in adolescent Caucasians. At the genome level, a pathognomonic EWSR1-ETS translocation is present. The resulting fusion protein acts as a molecular driver in the tumor development and interferes, amongst others, with endogenous transcription and splicing. The Ewing sarcoma cell shows a poorly differentiated, stem-cell like phenotype. Consequently, the cellular origin of Ewing sarcoma is still a hot discussed topic. To further characterize Ewing sarcoma and to further elucidate the role of EWSR1-ETS fusion protein multiple genome, epigenome and transcriptome level studies were performed. In this review, the data from these studies were combined into a comprehensive overview. Presently, classical morphological predictive markers are used in the clinic and the therapy is dominantly based on systemic chemotherapy in combination with surgical interventions. Using sequencing, novel predictive markers and candidates for immuno- and targeted therapy were identified which were summarized in this review.
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Affiliation(s)
- Laurens G L Sand
- Department of Pathology, Leiden University Medical Center, Leiden 2333 ZA, The Netherlands.
| | - Karoly Szuhai
- Department of Molecular Cell Biology, Leiden University Medical Center, Leiden 2333 ZA, The Netherlands.
| | - Pancras C W Hogendoorn
- Department of Pathology, Leiden University Medical Center, Leiden 2333 ZA, The Netherlands.
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18
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Hsiao JJ, Ng BH, Smits MM, Wang J, Jasavala RJ, Martinez HD, Lee J, Alston JJ, Misonou H, Trimmer JS, Wright ME. Androgen receptor and chemokine receptors 4 and 7 form a signaling axis to regulate CXCL12-dependent cellular motility. BMC Cancer 2015; 15:204. [PMID: 25884570 PMCID: PMC4393632 DOI: 10.1186/s12885-015-1201-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Accepted: 03/17/2015] [Indexed: 11/21/2022] Open
Abstract
Background Identifying cellular signaling pathways that become corrupted in the presence of androgens that increase the metastatic potential of organ-confined tumor cells is critical to devising strategies capable of attenuating the metastatic progression of hormone-naïve, organ-confined tumors. In localized prostate cancers, gene fusions that place ETS-family transcription factors under the control of androgens drive gene expression programs that increase the invasiveness of organ-confined tumor cells. C-X-C chemokine receptor type 4 (CXCR4) is a downstream target of ERG, whose upregulation in prostate-tumor cells contributes to their migration from the prostate gland. Recent evidence suggests that CXCR4-mediated proliferation and metastasis of tumor cells is regulated by CXCR7 through its scavenging of chemokine CXCL12. However, the role of androgens in regulating CXCR4-mediated motility with respect to CXCR7 function in prostate-cancer cells remains unclear. Methods Immunocytochemistry, western blot, and affinity-purification analyses were used to study how androgens influenced the expression, subcellular localization, and function of CXCR7, CXCR4, and androgen receptor (AR) in LNCaP prostate-tumor cells. Moreover, luciferase assays and quantitative polymerase chain reaction (qPCR) were used to study how chemokines CXCL11 and CXCL12 regulate androgen-regulated genes (ARGs) in LNCaP prostate-tumor cells. Lastly, cell motility assays were carried out to determine how androgens influenced CXCR4-dependent motility through CXCL12. Results Here we show that, in the LNCaP prostate-tumor cell line, androgens coordinate the expression of CXCR4 and CXCR7, thereby promoting CXCL12/CXCR4-mediated cell motility. RNA interference experiments revealed functional interactions between AR and CXCR7 in these cells. Co-localization and affinity-purification experiments support a physical interaction between AR and CXCR7 in LNCaP cells. Unexpectedly, CXCR7 resided in the nuclear compartment and modulated AR-mediated transcription. Moreover, androgen-mediated cell motility correlated positively with the co-localization of CXCR4 and CXCR7 receptors, suggesting that cell migration may be linked to functional CXCR4/CXCR7 heterodimers. Lastly, CXCL12-mediated cell motility was CXCR7-dependent, with CXCR7 expression required for optimal expression of CXCR4 protein. Conclusions Overall, our results suggest that inhibition of CXCR7 function might decrease the metastatic potential of organ-confined prostate cancers. Electronic supplementary material The online version of this article (doi:10.1186/s12885-015-1201-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jordy J Hsiao
- Department of Molecular Physiology & Biophysics, The University of Iowa, Carver College of Medicine, 51 Newton Road, Iowa City, Iowa, 52242, USA.
| | - Brandon H Ng
- Department of Molecular Physiology & Biophysics, The University of Iowa, Carver College of Medicine, 51 Newton Road, Iowa City, Iowa, 52242, USA.
| | - Melinda M Smits
- Department of Molecular Physiology & Biophysics, The University of Iowa, Carver College of Medicine, 51 Newton Road, Iowa City, Iowa, 52242, USA.
| | - Jiahui Wang
- Department of Molecular Physiology & Biophysics, The University of Iowa, Carver College of Medicine, 51 Newton Road, Iowa City, Iowa, 52242, USA.
| | - Rohini J Jasavala
- Department of Pharmacology, Davis Genome Center, University of California Davis School of Medicine, One Shields Avenue, Davis, California, 95616, USA.
| | - Harryl D Martinez
- Department of Molecular Physiology & Biophysics, The University of Iowa, Carver College of Medicine, 51 Newton Road, Iowa City, Iowa, 52242, USA.
| | - Jinhee Lee
- Department of Molecular Physiology & Biophysics, The University of Iowa, Carver College of Medicine, 51 Newton Road, Iowa City, Iowa, 52242, USA.
| | - Jhullian J Alston
- Department of Molecular Physiology & Biophysics, The University of Iowa, Carver College of Medicine, 51 Newton Road, Iowa City, Iowa, 52242, USA.
| | - Hiroaki Misonou
- Graduate School of Brain Science, Doshisha University, Kyoto, Japan.
| | - James S Trimmer
- Department of Neurobiology, Physiology and Behavior and Department of Physiology and Membrane Biology, University of California Davis, School of Medicine, One Shields Avenue, Davis, California, 95616, USA.
| | - Michael E Wright
- Department of Molecular Physiology & Biophysics, The University of Iowa, Carver College of Medicine, 51 Newton Road, Iowa City, Iowa, 52242, USA.
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19
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Xu T, Zhu Z, Sun Y, Ren L, Wang R. Characterization and expression of the CXCR1 and CXCR4 in miiuy croaker and evolutionary analysis shows the strong positive selection pressures imposed in mammal CXCR1. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2014; 44:133-144. [PMID: 24333436 DOI: 10.1016/j.dci.2013.12.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Revised: 11/29/2013] [Accepted: 12/02/2013] [Indexed: 06/03/2023]
Abstract
The innate immune system can recognize non-self, danger signals, and pathogen associated molecular patterns and provides a first line of antimicrobial host defense. Therefore, it plays an instructive role and is pretty important in vertebrates. In innate immune responses, CXCRs act as the main receptors of CXC chemokines and play a vital role in host defense and inflammation. In present study, we cloned two cDNA molecules of CXCR1 and CXCR4 in Miichthys miiuy (miiuy croaker). In these two genes, we found the most highly conserved DRY motif in the second intracellular loop adjacent to the third transmembrane domain. The expressions of CXCR1 and CXCR4 showed that they were ubiquitously expressed in ten normal tissues. After infection with Vibrio anguillarum and Vibrio harveyi, the expressions of CXCRs in the immune tissues were significantly regulated in most of tissues except that of CXCR1 in the kidney after V. harveyi injection. Evolutionary analysis showed that only the ancestral lineages of CXCR4 in amphibians underwent positive selection, indicating that the ancestors of amphibians boarded the land and had to further evolve to adapt to terrestrial environments. Multiple ML methods were implemented to detect the robust positively selected candidates for sites. In total, we detected 12 and 3 positively selected sites in the subsets of current mammal and fish CXCR1 genes, and only one site under positive selection was found in mammalian CXCR4 subsets. These positively selected sites were mainly located in the extracellular domains of CXCRs. The sliding window analysis and evolution test tended to favor positive selection acting on the N-terminal domain of CXCR1, which was the critical region for ligand/receptor signaling for neutrophils and receptor-ligand interaction, indicating that the N-terminal of CXCR1 in mammals underwent more positive selection than that of fish.
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Affiliation(s)
- Tianjun Xu
- Laboratory of Fish Biogenetics & Immune Evolution, College of Marine Science, Zhejiang Ocean University, Zhoushan, PR China.
| | - Zhihuang Zhu
- Laboratory of Fish Biogenetics & Immune Evolution, College of Marine Science, Zhejiang Ocean University, Zhoushan, PR China
| | - Yuena Sun
- Laboratory of Fish Biogenetics & Immune Evolution, College of Marine Science, Zhejiang Ocean University, Zhoushan, PR China
| | - Liping Ren
- Laboratory of Fish Biogenetics & Immune Evolution, College of Marine Science, Zhejiang Ocean University, Zhoushan, PR China
| | - Rixin Wang
- Laboratory of Fish Biogenetics & Immune Evolution, College of Marine Science, Zhejiang Ocean University, Zhoushan, PR China
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20
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Molecular recognition of CXCR4 by a dual tropic HIV-1 gp120 V3 loop. Biophys J 2014; 105:1502-14. [PMID: 24048002 DOI: 10.1016/j.bpj.2013.07.049] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2013] [Revised: 07/16/2013] [Accepted: 07/29/2013] [Indexed: 01/01/2023] Open
Abstract
HIV-1 cell entry is initiated by the interaction of the viral envelope glycoprotein gp120 with CD4, and chemokine coreceptors CXCR4 and CCR5. The molecular recognition of CXCR4 or CCR5 by the HIV-1 gp120 is mediated through the V3 loop, a fragment of gp120. The binding of the V3 loop to CXCR4 or CCR5 determines the cell tropism of HIV-1 and constitutes a key step before HIV-1 cell entry. Thus, elucidating the molecular recognition of CXCR4 by the V3 loop is important for understanding HIV-1 viral infectivity and tropism, and for the design of HIV-1 inhibitors. We employed a comprehensive set of computational tools, predominantly based on free energy calculations and molecular-dynamics simulations, to investigate the molecular recognition of CXCR4 by a dual tropic V3 loop. We report what is, to our knowledge, the first HIV-1 gp120 V3 loop:CXCR4 complex structure. The computationally derived structure reveals an abundance of polar and nonpolar intermolecular interactions contributing to the HIV-1 gp120:CXCR4 binding. Our results are in remarkable agreement with previous experimental findings. Therefore, this work sheds light on the functional role of HIV-1 gp120 V3 loop and CXCR4 residues associated with HIV-1 coreceptor activity.
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21
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Ping LH, Joseph SB, Anderson JA, Abrahams MR, Salazar-Gonzalez JF, Kincer LP, Treurnicht FK, Arney L, Ojeda S, Zhang M, Keys J, Potter EL, Chu H, Moore P, Salazar MG, Iyer S, Jabara C, Kirchherr J, Mapanje C, Ngandu N, Seoighe C, Hoffman I, Gao F, Tang Y, Labranche C, Lee B, Saville A, Vermeulen M, Fiscus S, Morris L, Karim SA, Haynes BF, Shaw GM, Korber BT, Hahn BH, Cohen MS, Montefiori D, Williamson C, Swanstrom R. Comparison of viral Env proteins from acute and chronic infections with subtype C human immunodeficiency virus type 1 identifies differences in glycosylation and CCR5 utilization and suggests a new strategy for immunogen design. J Virol 2013; 87:7218-33. [PMID: 23616655 PMCID: PMC3700278 DOI: 10.1128/jvi.03577-12] [Citation(s) in RCA: 95] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2013] [Accepted: 04/15/2013] [Indexed: 12/18/2022] Open
Abstract
Understanding human immunodeficiency virus type 1 (HIV-1) transmission is central to developing effective prevention strategies, including a vaccine. We compared phenotypic and genetic variation in HIV-1 env genes from subjects in acute/early infection and subjects with chronic infections in the context of subtype C heterosexual transmission. We found that the transmitted viruses all used CCR5 and required high levels of CD4 to infect target cells, suggesting selection for replication in T cells and not macrophages after transmission. In addition, the transmitted viruses were more likely to use a maraviroc-sensitive conformation of CCR5, perhaps identifying a feature of the target T cell. We confirmed an earlier observation that the transmitted viruses were, on average, modestly underglycosylated relative to the viruses from chronically infected subjects. This difference was most pronounced in comparing the viruses in acutely infected men to those in chronically infected women. These features of the transmitted virus point to selective pressures during the transmission event. We did not observe a consistent difference either in heterologous neutralization sensitivity or in sensitivity to soluble CD4 between the two groups, suggesting similar conformations between viruses from acute and chronic infection. However, the presence or absence of glycosylation sites had differential effects on neutralization sensitivity for different antibodies. We suggest that the occasional absence of glycosylation sites encoded in the conserved regions of env, further reduced in transmitted viruses, could expose specific surface structures on the protein as antibody targets.
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Affiliation(s)
- Li-Hua Ping
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Sarah B. Joseph
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Jeffrey A. Anderson
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Division of Infectious Diseases, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Melissa-Rose Abrahams
- Institute of Infectious Diseases and Molecular Medicine, Division of Medical Virology, University of Cape Town and National Health Laboratory Services, Cape Town, South Africa
| | | | - Laura P. Kincer
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Florette K. Treurnicht
- Institute of Infectious Diseases and Molecular Medicine, Division of Medical Virology, University of Cape Town and National Health Laboratory Services, Cape Town, South Africa
| | - Leslie Arney
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Suany Ojeda
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Ming Zhang
- Theoretical Biology, Los Alamos National Laboratory, Los Alamos, New Mexico, USA
- Department of Epidemiology and Biostatistics, University of Georgia, Athens, Georgia, USA
| | - Jessica Keys
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - E. Lake Potter
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Haitao Chu
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Penny Moore
- Centre for HIV and STIs, National Institute for Communicable Diseases, Johannesburg, South Africa
| | - Maria G. Salazar
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Shilpa Iyer
- Departments of Medicine and Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Cassandra Jabara
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Jennifer Kirchherr
- Duke Human Vaccine Institute, Department of Medicine, Duke University, Durham, North Carolina, USA
| | | | - Nobubelo Ngandu
- Institute of Infectious Diseases and Molecular Medicine, Division of Medical Virology, University of Cape Town and National Health Laboratory Services, Cape Town, South Africa
| | | | - Irving Hoffman
- Division of Infectious Diseases, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Feng Gao
- Duke Human Vaccine Institute, Department of Medicine, Duke University, Durham, North Carolina, USA
| | - Yuyang Tang
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Celia Labranche
- Department of Surgery, Duke University, Durham, North Carolina, USA
| | - Benhur Lee
- Department of Microbiology, Immunology and Molecular Genetics, University of California at Los Angeles, Los Angeles, California, USA
| | - Andrew Saville
- South African National Blood Service, Weltevreden Park, South Africa
| | - Marion Vermeulen
- South African National Blood Service, Weltevreden Park, South Africa
| | - Susan Fiscus
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Lynn Morris
- Centre for HIV and STIs, National Institute for Communicable Diseases, Johannesburg, South Africa
| | - Salim Abdool Karim
- Center for AIDS Program Research in South Africa, Doris Duke Medical Research Institute, University of KwaZulu-Natal, Durban, South Africa
| | - Barton F. Haynes
- Duke Human Vaccine Institute, Department of Medicine, Duke University, Durham, North Carolina, USA
| | - George M. Shaw
- Departments of Medicine and Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Bette T. Korber
- Los Alamos National Laboratory, Los Alamos, New Mexico, USA
- Santa Fe Institute, Santa Fe, New Mexico, USA
| | - Beatrice H. Hahn
- Departments of Medicine and Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Myron S. Cohen
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Division of Infectious Diseases, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - David Montefiori
- Department of Surgery, Duke University, Durham, North Carolina, USA
| | - Carolyn Williamson
- Institute of Infectious Diseases and Molecular Medicine, Division of Medical Virology, University of Cape Town and National Health Laboratory Services, Cape Town, South Africa
| | - Ronald Swanstrom
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
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22
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Transmitted/founder and chronic HIV-1 envelope proteins are distinguished by differential utilization of CCR5. J Virol 2012; 87:2401-11. [PMID: 23269796 DOI: 10.1128/jvi.02964-12] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Infection by HIV-1 most often results from the successful transmission and propagation of a single virus variant, termed the transmitted/founder (T/F) virus. Here, we compared the attachment and entry properties of envelope (Env) glycoproteins from T/F and chronic control (CC) viruses. Using a panel of 40 T/F and 47 CC Envs, all derived by single genome amplification, we found that 52% of clade C and B CC Envs exhibited partial resistance to the CCR5 antagonist maraviroc (MVC) on cells expressing high levels of CCR5, while only 15% of T/F Envs exhibited this same property. Moreover, subtle differences in the magnitude with which MVC inhibited infection on cells expressing low levels of CCR5, including primary CD4(+) T cells, were highly predictive of MVC resistance when CCR5 expression levels were high. These results are consistent with previous observations showing a greater sensitivity of T/F Envs to MVC inhibition on cells expressing very high levels of CCR5 and indicate that CC Envs are often capable of recognizing MVC-bound CCR5, albeit inefficiently on cells expressing physiologic levels of CCR5. When CCR5 expression levels are high, this phenotype becomes readily detectable. The utilization of drug-bound CCR5 conformations by many CC Envs was seen with other CCR5 antagonists, with replication-competent viruses, and did not obviously correlate with other phenotypic traits. The striking ability of clade C and B CC Envs to use MVC-bound CCR5 relative to T/F Envs argues that the more promiscuous use of CCR5 by these Env proteins is selected against at the level of virus transmission and is selected for during chronic infection.
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Boulais PE, Escher E, Leduc R. Analysis by substituted cysteine scanning mutagenesis of the fourth transmembrane domain of the CXCR4 receptor in its inactive and active state. Biochem Pharmacol 2012; 85:541-50. [PMID: 23219524 DOI: 10.1016/j.bcp.2012.11.022] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Revised: 11/23/2012] [Accepted: 11/27/2012] [Indexed: 11/28/2022]
Abstract
The chemokine SDF-1 (CXCL12) selectively binds to CXCR4, a member of the G protein-coupled receptor (GPCR) superfamily. In this study, we used the substituted-cysteine accessibility method (SCAM) to identify specific residues of the fourth transmembrane domain (TM4) that contribute to the formation of the binding pocket of CXCR4 in its inactive and active state. We successively substituted each residue from E179((4.68)) to K154((4.43)) with cysteine and expressed the mutants in COS-7 cells. Mutant receptors were then alkylated with methanethiosulfonate-ethylammonium (MTSEA), and binding inhibition was monitored using the CXCR4 antagonist FC131 [cyclo(-D-Tyr(1)-Arg(2)-Arg(3)-Nal(4)-Gly(5)-)], which displays anti-HIV activity. MTSEA treatment resulted in a significant reduction of FC131 binding to D171C((4.60)) and P170C((4.59)). To assess TM4 accessibility in an active state of CXCR4, TM4 cysteine mutants were transposed within the constitutively active mutant N119S((3.35)). MTSEA treatment of TM4 mutants N119S-S178C((4.67)), N119S-V177C((4.66)) and N119S-I173C((4.62)) resulted in a significant reduction in FC131 binding. Protection assays using FC131 prior to MTSEA treatment significantly reduced the alkylation of all MTSEA-sensitive mutants. The accessibility of the D171C((4.60)) and P170C((4.59)) residues suggests that they are oriented towards a water-accessible area of the binding pocket of CXCR4. S178C((4.67)), V177C((4.66)) and I173C((4.62)) showed binding inhibition only in an N119S((3.35)) background. Taken together our results suggest that TM4 and ECL2 undergo conformational changes during CXCR4 activation and also demonstrate how TM4 is an important feature for the binding of anti-HIV compounds.
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Affiliation(s)
- Philip E Boulais
- Department of Pharmacology, Institut de Pharmacologie de Sherbrooke, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec J1H5N4, Canada
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Kriechbaumer V, Nabok A, Widdowson R, Smith DP, Abell BM. Quantification of ligand binding to G-protein coupled receptors on cell membranes by ellipsometry. PLoS One 2012; 7:e46221. [PMID: 23049983 PMCID: PMC3458955 DOI: 10.1371/journal.pone.0046221] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Accepted: 08/28/2012] [Indexed: 12/18/2022] Open
Abstract
G-protein-coupled receptors (GPCRs) are prime drug targets and targeted by approximately 60% of current therapeutic drugs such as β-blockers, antipsychotics and analgesics. However, no biophysical methods are available to quantify their interactions with ligand binding in a native environment. Here, we use ellipsometry to quantify specific interactions of receptors within native cell membranes. As a model system, the GPCR-ligand CXCL12α and its receptor CXCR4 are used. Human-derived Ishikawa cells were deposited onto gold coated slides via Langmuir-Schaefer film deposition and interactions between the receptor CXCR4 on these cells and its ligand CXCL12α were detected via total internal reflection ellipsometry (TIRE). This interaction could be inhibited by application of the CXCR4-binding drug AMD3100. Advantages of this approach are that it allows measurement of interactions in a lipid environment without the need for labelling, protein purification or reconstitution of membrane proteins. This technique is potentially applicable to a wide variety of cell types and their membrane receptors, providing a novel method to determine ligand or drug interactions targeting GPCRs and other membrane proteins.
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Affiliation(s)
- Verena Kriechbaumer
- Biomedical Research Centre, Sheffield Hallam University, Sheffield, United Kingdom.
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Szpakowska M, Fievez V, Arumugan K, van Nuland N, Schmit JC, Chevigné A. Function, diversity and therapeutic potential of the N-terminal domain of human chemokine receptors. Biochem Pharmacol 2012; 84:1366-80. [PMID: 22935450 DOI: 10.1016/j.bcp.2012.08.008] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2012] [Revised: 08/08/2012] [Accepted: 08/09/2012] [Indexed: 11/16/2022]
Abstract
Chemokines and their receptors play fundamental roles in many physiological and pathological processes such as leukocyte trafficking, inflammation, cancer and HIV-1 infection. Chemokine-receptor interactions are particularly intricate and therefore require precise orchestration. The flexible N-terminal domain of human chemokine receptors has regularly been demonstrated to hold a crucial role in the initial recognition and selective binding of the receptor ligands. The length and the amino acid sequences of the N-termini vary considerably among different receptors but they all show a high content of negatively charged residues and are subject to post-translational modifications such as O-sulfation and N- or O-glycosylation. In addition, a conserved cysteine that is most likely engaged in a receptor-stabilizing disulfide bond delimits two functionally distinct parts in the N-terminus, characterized by specific molecular signatures. Structural analyses have shown that the N-terminus of chemokine receptors recognizes a groove on the chemokine surface and that this interaction is stabilized by high-affinity binding to a conserved sulfotyrosine-binding pocket. Altogether, these data provide new insights on the chemokine-receptor molecular interplay and identify the receptor N-terminus-binding site as a new target for the development of therapeutic molecules. This review presents and discusses the diversity and function of human chemokine receptor N-terminal domains and provides a comprehensive annotated inventory of their sequences, laying special emphasis on the presence of post-translational modifications and functional features. Finally, it identifies new molecular signatures and proposes a computational model for the positioning and the conformation of the CXCR4 N-terminus grafted on the first chemokine receptor X-ray structure.
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Affiliation(s)
- Martyna Szpakowska
- Laboratory of Retrovirology, Public Research Center for Health, Luxembourg, Luxembourg.
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Kuil J, Buckle T, van Leeuwen FWB. Imaging agents for the chemokine receptor 4 (CXCR4). Chem Soc Rev 2012; 41:5239-61. [PMID: 22743644 DOI: 10.1039/c2cs35085h] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The interaction between the chemokine receptor 4 (CXCR4) and stromal cell-derived factor-1 (SDF-1, also known as CXCL12) is a natural regulatory process in the human body. However, CXCR4 over-expression is also found in diseases such as cancer, where it plays a role in, among others, the metastatic spread. For this reason it is an interesting biomarker for the field of diagnostic oncology, and therefore, it is gaining increasing interest for applications in molecular imaging. Especially "small-molecule" imaging agents based on T140, FC131 and AMD3100 have been extensively studied. SDF-1, antibodies, pepducins and bioluminescence have also been used to visualize CXCR4. In this critical review reported CXCR4 targeting imaging agents are described based on their affinity, specificity and biodistribution. The level wherein CXCR4 is up-regulated in cancer patients and its relation to the different cell lines and animal models used to evaluate the efficacy of the imaging agents is also discussed (221 references).
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Affiliation(s)
- Joeri Kuil
- Department of Radiology, Interventional Molecular Imaging, Leiden University Medical Center, 2300 RC, Leiden, The Netherlands
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Endo M, Gejima S, Endo A, Takamune N, Shoji S, Misumi S. Treatment of breast cancer cells with proteasome inhibitor lactacystin increases the level of sensitivity to cell death induced by human immunodeficiency virus type 1. Biol Pharm Bull 2011; 33:1903-6. [PMID: 21048319 DOI: 10.1248/bpb.33.1903] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Upon binding to CD4, the human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein gp120 undergoes conformational changes that facilitate subsequent interactions with the chemokine coreceptor CXCR4 on the T cells. Our previous study showed that HIV-1 induces breast cancer cell death through gp120-CXCR4 interaction without CD4-induced conformational change of gp120. To characterize the structural properties of CXCR4 on breast cancer cells, the structural differences in CXCR4 between breast cancer cell lines and T cells were investigated. Immunoblots of whole cell lysates from breast cancer cell and T cell lines demonstrated that the predominant forms of CXCR4 on the breast cancer cell lines and T cell lines were three species (45, 61, 100 kDa) and one species (45 kDa), respectively. Cell surface biotin labeling revealed that the 100-kDa polyubiquitinated form of CXCR4 is specifically expressed on the surface of breast cancer cell line DU4475 but not T cell line Molt4#8. The treatment of breast cancer cell lines MDA-MB231 and DU4475 with proteasome inhibitor lactacystin leads to increased surface expression of the 100-kDa polyubiquitinated form of CXCR4 and increases the level of sensitivity to cell death induced by HIV-1. These data suggest that the 100-kDa polyubiquitinated form of CXCR4 plays an important role as a trigger for gp120-induced breast cancer cell death.
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Affiliation(s)
- Masafumi Endo
- Department of Pharmaceutical Biochemistry, Faculty of Medical and Pharmaceutical Sciences, Kumamoto University, 5–1 Oe-honmachi, Kumamoto 862–0973, Japan
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Multiple CCR5 conformations on the cell surface are used differentially by human immunodeficiency viruses resistant or sensitive to CCR5 inhibitors. J Virol 2011; 85:8227-40. [PMID: 21680525 DOI: 10.1128/jvi.00767-11] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Resistance to small-molecule CCR5 inhibitors arises when HIV-1 variants acquire the ability to use inhibitor-bound CCR5 while still recognizing free CCR5. Two isolates, CC101.19 and D1/85.16, became resistant via four substitutions in the gp120 V3 region and three in the gp41 fusion peptide (FP), respectively. The binding characteristics of a panel of monoclonal antibodies (MAbs) imply that several antigenic forms of CCR5 are expressed at different levels on the surfaces of U87-CD4-CCR5 cells and primary CD4(+) T cells, in a cell-type-dependent manner. CCR5 binding and HIV-1 infection inhibition experiments suggest that the two CCR5 inhibitor-resistant viruses altered their interactions with CCR5 in different ways. As a result, both mutants became generally more sensitive to inhibition by CCR5 MAbs, and the FP mutant is specifically sensitive to a MAb that stains discrete cell surface clusters of CCR5 that may correspond to lipid rafts. We conclude that some MAbs detect different antigenic forms of CCR5 and that inhibitor-sensitive and -resistant viruses can use these CCR5 forms differently for entry in the presence or absence of CCR5 inhibitors.
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Tagliamonte M, Tornesello ML, Buonaguro FM, Buonaguro L. Conformational HIV-1 envelope on particulate structures: a tool for chemokine coreceptor binding studies. J Transl Med 2011; 9 Suppl 1:S1. [PMID: 21284899 PMCID: PMC3105500 DOI: 10.1186/1479-5876-9-s1-s1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The human immunodeficiency virus type 1 (HIV-1) external envelope glycoprotein gp120 presents conserved binding sites for binding to the primary virus receptor CD4 as well as the major HIV chemokine coreceptors, CCR5 and CXCR4. Concerted efforts are underway to understand the specific interactions between gp120 and coreceptors as well as their contribution to the subsequent membrane fusion process. The present review summarizes the current knowledge on this biological aspect, which represents one of the key and essential points of the HIV-host cell interplay and HIV life cycle. The relevance of conformational HIV-1 Envelope proteins presented on Virus-like Particles for appropriate assessment of this molecular interaction, is also discussed.
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Affiliation(s)
- Maria Tagliamonte
- Lab, of Molecular Biology and Viral Oncogenesis & AIDS Reference Center, Istituto Nazionale Tumori Fond, G, Pascale, Naples, Italy
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Ferreira LM, Romão TP, de-Melo-Neto OP, Silva-Filha MHNL. The orthologue to the Cpm1/Cqm1 receptor in Aedes aegypti is expressed as a midgut GPI-anchored α-glucosidase, which does not bind to the insecticidal binary toxin. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2010; 40:604-610. [PMID: 20685335 DOI: 10.1016/j.ibmb.2010.05.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Revised: 05/14/2010] [Accepted: 05/27/2010] [Indexed: 05/29/2023]
Abstract
Aedes aegypti larvae are refractory to the insecticidal binary (Bin) toxin from Bacillus sphaericus, which is not able to bind to its target tissue in the larval midgut. In contrast, Culex pipiens larvae are highly susceptible to that toxin, which targets its midgut brush border membranes (BBMF) through the binding of the BinB subunit to specific receptors, the Cpm1/Cqm1 membrane-bound α-glucosidases. The identification of an Ae. aegypti gene encoding a Cpm1/Cqm1 orthologue, here named Aam1, led to the major goal of this study which was to investigate its expression. The aam1 transcript was found in larvae and adults from Ae. aegypti and a ≈73-kDa protein was recognized by an anti-Cqm1 antibody in midgut BBMF. The Aam1 protein displayed α-glucosidase activity and localized to the midgut epithelium, bound through a GPI anchor, similarly to Cpm1/Cqm1. However, no binding of native Aam1 was observed to the recombinant BinB subunit. Treatment of both proteins with endoglycosidase led to changes in the molecular weight of Aam1, but not Cqm1, implying that the former was glycosylated. The findings from this work rule out lack of receptors in larval stages, or its expression as soluble proteins, as a reason for Ae. aegypti refractoriness to Bin toxin.
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Affiliation(s)
- Lígia Maria Ferreira
- Department of Entomology, Centro de Pesquisas Aggeu Magalhães/FIOCRUZ, Av. Moraes Rego s/n, Cidade Universitária, Recife-PE 50670-420, Brazil
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31
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Wong JP, Reboul E, Molday RS, Kast J. A carboxy-terminal affinity tag for the purification and mass spectrometric characterization of integral membrane proteins. J Proteome Res 2009; 8:2388-96. [PMID: 19236039 DOI: 10.1021/pr801008c] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
G-protein-coupled receptors (GPCRs) and other structurally and functionally related membrane proteins represent particularly attractive targets for drug discovery. Integral membrane proteins are often difficult to purify from native contexts, and lack of sufficient quantities hampers subsequent structural and functional proteomic studies. We describe here an optimized enrichment strategy involving a membrane protein-compatible 1D4 affinity tag that is derived from the carboxy-terminal nine amino residues of bovine rhodopsin, and its corresponding tag-specific, high-affinity monoclonal antibody. When two GPCRs as well as two related ATP binding cassette (ABC) transporters are expressed in their functional forms in human cell lines, we have shown that a single detergent and wash condition can be employed for the purification of all said membrane proteins. Subsequent in-gel digestion with trypsin and mass spectrometric peptide analysis resulted in high sequence coverage for the ABC transporters ABCA1-1D4 and ABCA4-1D4. In contrast, digestion by various enzymatic combinations was necessary to obtain the best sequence coverage for affinity-enriched GPCRs CXCR4-1D4 and CCR5-1D4 as compared against other entries in an annotated spectrum library. Furthermore, specific enzyme combinations were necessary to produce suitable peptides for deducing N-glycosylation sites on CXCR4. Our results demonstrate that the 1D4-tag enrichment strategy is a versatile tool for the characterization of integral membrane proteins that can be employed for functional proteomic studies.
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Affiliation(s)
- Julie P Wong
- Biomedical Research Centre, Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
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32
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Naganawa S, Yokoyama M, Shiino T, Suzuki T, Ishigatsubo Y, Ueda A, Shirai A, Takeno M, Hayakawa S, Sato S, Tochikubo O, Kiyoura S, Sawada K, Ikegami T, Kanda T, Kitamura K, Sato H. Net positive charge of HIV-1 CRF01_AE V3 sequence regulates viral sensitivity to humoral immunity. PLoS One 2008; 3:e3206. [PMID: 18787705 PMCID: PMC2527523 DOI: 10.1371/journal.pone.0003206] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2008] [Accepted: 08/21/2008] [Indexed: 12/22/2022] Open
Abstract
The third variable region (V3) of the human immunodeficiency virus type 1 (HIV-1) envelope gp120 subunit participates in determination of viral infection coreceptor tropism and host humoral immune responses. Positive charge of the V3 plays a key role in determining viral coreceptor tropism. Here, we examined by bioinformatics, experimental, and protein modelling approaches whether the net positive charge of V3 sequence regulates viral sensitivity to humoral immunity. We chose HIV-1 CRF01_AE strain as a model virus to address the question. Diversity analyses using CRF01_AE V3 sequences from 37 countries during 1984 and 2005 (n = 1361) revealed that reduction in the V3's net positive charge makes V3 less variable due to limited positive selection. Consistently, neutralization assay using CRF01_AE V3 recombinant viruses (n = 30) showed that the reduction in the V3's net positive charge rendered HIV-1 less sensitive to neutralization by the blood anti-V3 antibodies. The especially neutralization resistant V3 sequences were the particular subset of the CCR5-tropic V3 sequences with net positive charges of +2 to +4. Molecular dynamics simulation of the gp120 monomers showed that the V3's net positive charge regulates the V3 configuration. This and reported gp120 structural data predict a less-exposed V3 with a reduced net positive charge in the native gp120 trimer context. Taken together, these data suggest a key role of the V3's net positive charge in the immunological escape and coreceptor tropism evolution of HIV-1 CRF01_AE in vivo. The findings have molecular implications for the adaptive evolution and vaccine design of HIV-1.
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Affiliation(s)
- Satoshi Naganawa
- Department of Public Health, Yokohama City University School of Medicine, Kanagawa, Japan
- Department of Pathology and Microbiology, Nihon University School of Medicine, Tokyo, Japan
| | - Masaru Yokoyama
- Center for Pathogen Genomics, National Institute of Infectious Diseases, Tokyo, Japan
| | - Teiichiro Shiino
- AIDS Research Center, National Institute of Infectious Diseases, Tokyo, Japan
| | - Takeyuki Suzuki
- Department of Internal Medicine and Clinical Immunology, Yokohama City University Graduate School of Medicine, Kanagawa, Japan
| | - Yoshiaki Ishigatsubo
- Department of Internal Medicine and Clinical Immunology, Yokohama City University Graduate School of Medicine, Kanagawa, Japan
| | - Atsuhisa Ueda
- Department of Internal Medicine and Clinical Immunology, Yokohama City University Graduate School of Medicine, Kanagawa, Japan
| | - Akira Shirai
- College of Nursing, Yokohama City University School of Medicine, Kanagawa, Japan
| | - Mitsuhiro Takeno
- Department of Internal Medicine and Clinical Immunology, Yokohama City University Graduate School of Medicine, Kanagawa, Japan
| | - Satoshi Hayakawa
- Department of Pathology and Microbiology, Nihon University School of Medicine, Tokyo, Japan
| | - Shigehiro Sato
- Department of Bacteriology, Iwate Medical University, Iwate, Japan
| | - Osamu Tochikubo
- Department of Public Health, Yokohama City University School of Medicine, Kanagawa, Japan
| | | | | | | | - Tadahito Kanda
- Center for Pathogen Genomics, National Institute of Infectious Diseases, Tokyo, Japan
| | - Katsuhiko Kitamura
- Department of Public Health, Yokohama City University School of Medicine, Kanagawa, Japan
| | - Hironori Sato
- Center for Pathogen Genomics, National Institute of Infectious Diseases, Tokyo, Japan
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Low AJ, Marchant D, Brumme CJ, Brumme ZL, Dong W, Sing T, Hogg RS, Montaner JS, Gill V, Cheung PK, Harrigan PR. CD4-dependent characteristics of coreceptor use and HIV type 1 V3 sequence in a large population of therapy-naive individuals. AIDS Res Hum Retroviruses 2008; 24:219-28. [PMID: 18240966 DOI: 10.1089/aid.2007.0140] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We investigated the associations between coreceptor use, V3 loop sequence, and CD4 count in a cross-sectional analysis of a large cohort of chronically HIV-infected, treatment-naive patients. HIV coreceptor usage was determined in the last pretherapy plasma sample for 977 individuals initiating HAART in British Columbia, Canada using the Monogram Trofile Tropism assay. Relative light unit (RLU) readouts from the Trofile assay, as well as HIV V3 loop sequence data, were examined as a function of baseline CD4 cell count for 953 (97%) samples with both phenotype and genotype data available. Median CCR5 RLUs were high for both R5 and X4-capable samples, while CXCR4 RLUs were orders of magnitude lower for X4 samples (p < 0.001). CCR5 RLUs in R5 samples (N = 799) increased with decreasing CD4 count (p < 0.001), but did not vary with plasma viral load (pVL) (p = 0.74). In X4 samples (N = 178), CCR5 RLUs decreased with decreasing CD4 count (p = 0.046) and decreasing pVL (p = 0.097), while CXCR4 RLUs increased with decreasing pVL (p = 0.0008) but did not vary with CD4 (p = 0.96). RLUs varied with the presence of substitutions at V3 loop positions 11, 25, and 6-8. The prevalence and impact of substitutions at codons 25 and 6-8 were CD4 dependent as was the presence of amino acid mixtures in the V3; substitutions at position 11 were CD4 independent. Assay RLU measures predictably vary with both immunological and virological parameters. The ability to predict X4 virus using genotypic determinants at positions 25 and 6-8 of the V3 loop is CD4 dependent, while position 11 appears to be CD4 independent.
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Affiliation(s)
- Andrew J. Low
- B.C. Centre for Excellence in HIV/AIDS, St. Paul's Hospital, Vancouver, British Columbia, Canada
- Faculty of Medicine, University of British Columbia, British Columbia, Canada
| | - David Marchant
- The iCAPTURE Centre, Department of Pathology and Laboratory Medicine, Vancouver, British Columbia, Canada
| | - Chanson J. Brumme
- B.C. Centre for Excellence in HIV/AIDS, St. Paul's Hospital, Vancouver, British Columbia, Canada
| | - Zabrina L. Brumme
- B.C. Centre for Excellence in HIV/AIDS, St. Paul's Hospital, Vancouver, British Columbia, Canada
| | - Winnie Dong
- B.C. Centre for Excellence in HIV/AIDS, St. Paul's Hospital, Vancouver, British Columbia, Canada
| | - Tobias Sing
- Max Planck Institute for Informatics, Saarbrücken, Germany
| | - Robert S. Hogg
- B.C. Centre for Excellence in HIV/AIDS, St. Paul's Hospital, Vancouver, British Columbia, Canada
| | - Julio S.G. Montaner
- B.C. Centre for Excellence in HIV/AIDS, St. Paul's Hospital, Vancouver, British Columbia, Canada
- Faculty of Medicine, University of British Columbia, British Columbia, Canada
| | - Vikram Gill
- B.C. Centre for Excellence in HIV/AIDS, St. Paul's Hospital, Vancouver, British Columbia, Canada
- Faculty of Medicine, University of British Columbia, British Columbia, Canada
| | - Peter K. Cheung
- B.C. Centre for Excellence in HIV/AIDS, St. Paul's Hospital, Vancouver, British Columbia, Canada
| | - P. Richard Harrigan
- B.C. Centre for Excellence in HIV/AIDS, St. Paul's Hospital, Vancouver, British Columbia, Canada
- Faculty of Medicine, University of British Columbia, British Columbia, Canada
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Lobo PI, Schlegel KH, Yuan W, Townsend GC, White JA. Inhibition of HIV-1 Infectivity through an Innate Mechanism Involving Naturally Occurring IgM Anti-Leukocyte Autoantibodies. THE JOURNAL OF IMMUNOLOGY 2008; 180:1769-79. [DOI: 10.4049/jimmunol.180.3.1769] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Lobo PI, Schlegel KH, Spencer CE, Okusa MD, Chisholm C, Mchedlishvili N, Park A, Christ C, Burtner C. Naturally Occurring IgM Anti-Leukocyte Autoantibodies (IgM-ALA) Inhibit T Cell Activation and Chemotaxis. THE JOURNAL OF IMMUNOLOGY 2008; 180:1780-91. [DOI: 10.4049/jimmunol.180.3.1780] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Brass AL, Dykxhoorn DM, Benita Y, Yan N, Engelman A, Xavier RJ, Lieberman J, Elledge SJ. Identification of host proteins required for HIV infection through a functional genomic screen. Science 2008; 319:921-6. [PMID: 18187620 DOI: 10.1126/science.1152725] [Citation(s) in RCA: 1109] [Impact Index Per Article: 69.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
HIV-1 exploits multiple host proteins during infection. We performed a large-scale small interfering RNA screen to identify host factors required by HIV-1 and identified more than 250 HIV-dependency factors (HDFs). These proteins participate in a broad array of cellular functions and implicate new pathways in the viral life cycle. Further analysis revealed previously unknown roles for retrograde Golgi transport proteins (Rab6 and Vps53) in viral entry, a karyopherin (TNPO3) in viral integration, and the Mediator complex (Med28) in viral transcription. Transcriptional analysis revealed that HDF genes were enriched for high expression in immune cells, suggesting that viruses evolve in host cells that optimally perform the functions required for their life cycle. This effort illustrates the power with which RNA interference and forward genetics can be used to expose the dependencies of human pathogens such as HIV, and in so doing identify potential targets for therapy.
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Affiliation(s)
- Abraham L Brass
- Department of Genetics, Center for Genetics and Genomics, Brigham and Women's Hospital, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA 02115, USA
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Kubo Y, Yokoyama M, Yoshii H, Mitani C, Tominaga C, Tanaka Y, Sato H, Yamamoto N. Inhibitory role of CXCR4 glycan in CD4-independent X4-tropic human immunodeficiency virus type 1 infection and its abrogation in CD4-dependent infection. J Gen Virol 2007; 88:3139-3144. [PMID: 17947541 DOI: 10.1099/vir.0.83202-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
CXCR4 functions as an infection receptor of X4 human immunodeficiency virus type 1 (HIV-1) . CXCR4 is glycosylated at the N-terminal extracellular region, which is important for viral envelope (Env) protein binding. We compared the effects of CXCR4 glycan on the CD4-dependent and -independent infections in human cells by X4 viruses. We found that transduction mediated by Env proteins of CD4-independent HIV-1 strains increased up to 5.5-fold in cells expressing unglycosylated CXCR4, suggesting that the CXCR4 glycan inhibits CD4-independent X4 virus infection. Co-expression of CD4 on the target cell surface or pre-incubation of virus particles with soluble CD4 abrogates the glycan-mediated inhibition of X4 virus infection, suggesting that interaction of Env protein with CD4 counteracts the inhibition. These findings indicate that it will be advantageous for X4 HIV-1 to remain CD4-dependent. A structural model that explains the glycan-mediated inhibition is discussed.
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Affiliation(s)
- Yoshinao Kubo
- Department of AIDS Research, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Masaru Yokoyama
- Laboratory of Viral Genomics, Center for Pathogen Genomics, National Institute of Infectious Diseases, Tokyo, Japan.,Department of AIDS Research, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Hiroaki Yoshii
- Department of AIDS Research, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Chiho Mitani
- Department of AIDS Research, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Chika Tominaga
- Department of AIDS Research, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Yuetsu Tanaka
- Department of Immunology, Graduate School and Faculty of Medicine, University of the Ryukyus, Okinawa, Japan
| | - Hironori Sato
- Laboratory of Viral Genomics, Center for Pathogen Genomics, National Institute of Infectious Diseases, Tokyo, Japan.,Department of AIDS Research, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Naoki Yamamoto
- Department of Molecular Virology, Tokyo Medical and Dental University, Tokyo, Japan.,AIDS Research Center, National Institute of Infectious Diseases, Tokyo, Japan.,Department of AIDS Research, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
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38
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Xu C, Sui J, Tao H, Zhu Q, Marasco WA. Human anti-CXCR4 antibodies undergo VH replacement, exhibit functional V-region sulfation, and define CXCR4 antigenic heterogeneity. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2007; 179:2408-18. [PMID: 17675502 DOI: 10.4049/jimmunol.179.4.2408] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The chemokine receptor CXCR4 and its ligand stromal-derived factor-1 (SDF-1/CXCL12) are essential for many biological processes and various pathological conditions. However, the relationship between CXCR4 antigenic structure and SDF-1-mediated biological responses is poorly understood. In this report, a panel of human anti-CXCR4 Abs were isolated and used to explore CXCR4 antigenic heterogeneity and function. Multiple fixed CXCR4 antigenic isoforms were detected on the surface of hemopoietic cells. Epitope mapping studies demonstrated the complex nature of the surface-exposed CXCR4 epitopes. Ab-mediated inhibition of chemotaxis correlated strongly with binding affinity, epitope recognition, as well as the level of CXCR4 isoform expression. In addition, detailed genetic analyses of these Abs showed evidence of V(H) replacement. Importantly, structural and biochemical studies demonstrated tyrosine sulfation in novel regions of the V genes that contributed bidirectionally to the binding activity of the Abs. These data provide the first evidence that functional tyrosine sulfation occurs in self-reactive Abs and suggest a potential new mechanism that may contribute to the pathogenesis of Ab-mediated autoimmune disease. These Abs also provide valuable tools to explore the selective in vivo targeting of CXCR4 isoforms that may be preferentially expressed in certain disease states and involved in steady-state CXCR4-SDF-1 homeostasis.
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Affiliation(s)
- Chen Xu
- Department of Cancer Immunology and AIDS, Dana-Farber Cancer Institute, Boston, MA, USA
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39
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McReynolds KD, Gervay-Hague J. Chemotherapeutic Interventions Targeting HIV Interactions with Host-Associated Carbohydrates. Chem Rev 2007; 107:1533-52. [PMID: 17439183 DOI: 10.1021/cr0502652] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Katherine D McReynolds
- Department of Chemistry, California State University, Sacramento, Sacramento, California 95819, USA.
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40
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Huskens D, Princen K, Schreiber M, Schols D. The role of N-glycosylation sites on the CXCR4 receptor for CXCL-12 binding and signaling and X4 HIV-1 viral infectivity. Virology 2007; 363:280-7. [PMID: 17331556 DOI: 10.1016/j.virol.2007.01.031] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2006] [Revised: 01/03/2007] [Accepted: 01/26/2007] [Indexed: 11/24/2022]
Abstract
The chemokine receptor CXCR4 functions as one of the HIV-1 coreceptors and can be considered as an attractive target for the development of novel anti-HIV drugs. Here, we investigated the effect of its two known N-glycosylation sites g1 (NYT) and g2 (NVS) on the antiviral potential of several classes of entry inhibitors. The lack of g1 clearly affected the binding of the amino-terminal directed 2B11 mAb, but not the 12G5 mAb. No dramatic effects on CXCL-12 binding and CXCL-12-induced intracellular calcium responses were observed. Importantly, the anti-HIV-1 activity and antagonistic activity of the prototype compound of CXCR4 inhibitors, AMD3100, were not affected by the presence or absence of the CXCR4 N-glycans. Since CXCR4 N-glycans play a less important role in viral entry compared to the N-glycans on the HIV envelope, cells expressing CXCR4 N-glycosylation mutants might be no relevant alternative to allow HIV-1 escape from antivirals.
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MESH Headings
- Amino Acid Sequence
- Amino Acids/physiology
- Anti-HIV Agents/pharmacology
- Antibodies/metabolism
- Antibodies/pharmacology
- Antibodies, Monoclonal/metabolism
- Antibodies, Monoclonal/pharmacology
- Benzylamines
- Binding Sites/physiology
- Cell Line, Tumor
- Chemokine CXCL12
- Chemokines, CXC/metabolism
- Chemokines, CXC/pharmacology
- Cyclams
- Drug Resistance, Viral
- Glycosylation
- HIV Fusion Inhibitors/pharmacology
- HIV-1/pathogenicity
- HIV-1/physiology
- Heterocyclic Compounds/metabolism
- Heterocyclic Compounds/pharmacology
- Humans
- Lectins/metabolism
- Lectins/pharmacology
- Molecular Sequence Data
- Mutation
- Protein Binding
- Protein Structure, Secondary
- Receptors, CXCR4/drug effects
- Receptors, CXCR4/genetics
- Receptors, CXCR4/immunology
- Receptors, CXCR4/metabolism
- Receptors, HIV/genetics
- Receptors, HIV/metabolism
- Signal Transduction
- Virulence
- Virus Replication
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Affiliation(s)
- Dana Huskens
- Rega Institute for Medical Research, Katholieke Universiteit Leuven, Minderbroedersstraat 10, B-3000 Leuven, Belgium
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41
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Busillo JM, Benovic JL. Regulation of CXCR4 signaling. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2006; 1768:952-63. [PMID: 17169327 PMCID: PMC1952230 DOI: 10.1016/j.bbamem.2006.11.002] [Citation(s) in RCA: 451] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2006] [Accepted: 11/04/2006] [Indexed: 12/31/2022]
Abstract
The chemokine receptor CXCR4 belongs to the large superfamily of G protein-coupled receptors, and is directly involved in a number of biological processes including organogenesis, hematopoiesis, and immune response. Recent evidence has highlighted the role of CXCR4 in a variety of diseases including HIV, cancer, and WHIM syndrome. Importantly, the involvement of CXCR4 in cancer metastasis and WHIM syndrome appears to be due to dysregulation of the receptor leading to enhanced signaling. Herein we review what is currently known regarding the regulation of CXCR4 and how dysregulation contributes to disease progression.
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Affiliation(s)
- John M. Busillo
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, PA 19107
| | - Jeffrey L. Benovic
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, Philadelphia, PA 19107
- To whom correspondence should be addressed:
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42
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Venzke S, Michel N, Allespach I, Fackler OT, Keppler OT. Expression of Nef downregulates CXCR4, the major coreceptor of human immunodeficiency virus, from the surfaces of target cells and thereby enhances resistance to superinfection. J Virol 2006; 80:11141-52. [PMID: 16928758 PMCID: PMC1642143 DOI: 10.1128/jvi.01556-06] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Lentiviral Nef proteins are key factors for pathogenesis and are known to downregulate functionally important molecules, including CD4 and major histocompatibility complex class I (MHC-I), from the surfaces of infected cells. Recently, we demonstrated that Nef reduces cell surface levels of the human immunodeficiency virus type 1 (HIV-1) entry coreceptor CCR5 (N. Michel, I. Allespach, S. Venzke, O. T. Fackler, and O. T. Keppler, Curr. Biol. 15:714-723, 2005). Here, we report that Nef downregulates the second major HIV-1 coreceptor, CXCR4, from the surfaces of HIV-infected primary CD4 T lymphocytes with efficiencies comparable to those of the natural CXCR4 ligand, stromal cell-derived factor-1 alpha. Analysis of a panel of mutants of HIV-1(SF2) Nef revealed that the viral protein utilized the same signature motifs for downmodulation of CXCR4 and MHC-I, including the proline-rich motif P(73)P(76)P(79)P(82) and the acidic cluster motif E(66)E(67)E(68)E(69.) Expression of wild-type Nef, but not of specific Nef mutants, resulted in a perinuclear accumulation of the coreceptor. Remarkably, the carboxy terminus of CXCR4, which harbors the classical motifs critical for basal and ligand-induced receptor endocytosis, was dispensable for the Nef-mediated reduction of surface exposure. Functionally, the ability of Nef to simultaneously downmodulate CXCR4 and CD4 correlated with maximum-level protection of Nef-expressing target cells from fusion with cells exposing X4 HIV-1 envelopes. Furthermore, the Nef-mediated downregulation of CXCR4 alone on target T lymphocytes was sufficient to diminish cells' susceptibility to X4 HIV-1 virions at the entry step. The downregulation of chemokine coreceptors is a conserved activity of Nef to modulate infected cells, an important functional consequence of which is an enhanced resistance to HIV superinfection.
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Affiliation(s)
- Stephanie Venzke
- Department of Virology, University of Heidelberg, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany
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43
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Dukkipati A, Vaclavikova J, Waghray D, Garcia KC. In vitro reconstitution and preparative purification of complexes between the chemokine receptor CXCR4 and its ligands SDF-1alpha, gp120-CD4 and AMD3100. Protein Expr Purif 2006; 50:203-14. [PMID: 16962791 DOI: 10.1016/j.pep.2006.07.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2006] [Revised: 07/13/2006] [Accepted: 07/23/2006] [Indexed: 01/18/2023]
Abstract
CXCR4 belongs to the family of G protein-coupled receptors and mediates the various developmental and regulatory effects of the chemokine SDF-1alpha. In addition, CXCR4 acts as a co-receptor along with CD4 for the HIV-1 viral glycoprotein gp120. Recently, there has also been a small molecule described that antagonizes both SDF-1 and gp120 binding to CXCR4. The structural and mechanistic basis for this dual recognition ability of CXCR4 is unknown largely due to the technical challenges of biochemically producing the components of the various complexes. We expressed the human CXCR4 receptor using a modified baculovirus expression vector that facilitates a single step antibody affinity purification of CXCR4 to >80% purity from Hi5 cells. The recombinant receptor undergoes N-linked glycosylation, tyrosine sulfation and is recognized by the 12G5 conformation specific antibody against human CXCR4. We are able to purify CXCR4 alone as well as complexed with its endogenous ligand SDF-1, its viral ligand gp120, and a small molecule antagonist AMD3100 by ion-exchange chromatography. We anticipate that the expression and purification scheme described in this paper will facilitate structure-function studies aimed at elucidating the molecular basis for CXCR4 recognition of its endogenous chemokine and viral ligands.
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Affiliation(s)
- Abhiram Dukkipati
- Department of Microbiology and Immunology, Stanford University School of Medicine, 299 Campus Drive, Stanford, CA 94305, USA
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44
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Clevestig P, Pramanik L, Leitner T, Ehrnst A. CCR5 use by human immunodeficiency virus type 1 is associated closely with the gp120 V3 loop N-linked glycosylation site. J Gen Virol 2006; 87:607-612. [PMID: 16476981 DOI: 10.1099/vir.0.81510-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Human immunodeficiency virus type 1 (HIV-1) enters cells through the chemokine receptors CCR5 (R5 virus) and/or CXCR4 (X4 virus). Loss of N-linked glycans and increased net charge of the third variable loop (V3) of the gp120 envelope glycoprotein have been observed to be important steps towards CXCR4 use. All reported sequences using CCR5 or CXCR4 exclusively, or using both, were gathered from the Los Alamos HIV Database and analysed with regard to the V3 N-linked glycosylation motifs (sequons) and charge. The V3 loop glycan had a sensitivity of 0.98 and a 0.92 positive predictive value in the context of CCR5 use. The difference from X4 was remarkable (P<10(-12)). Especially, the sequon motif NNT within the V3 loop was conserved in 99.2 % of the major clades. The results suggest a close association between the V3 loop glycan and CCR5 use and may provide new insight into HIV-1 tropism and help to improve phenotype-prediction models.
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Affiliation(s)
- Peter Clevestig
- Microbiology and Tumor Biology Center, Karolinska Institutet, Box 280, SE-171 77 Stockholm, Sweden
| | - Lotta Pramanik
- Microbiology and Tumor Biology Center, Karolinska Institutet, Box 280, SE-171 77 Stockholm, Sweden
| | - Thomas Leitner
- Theoretical Biology and Biophysics Group, Los Alamos National Laboratory, Los Alamos, NM, USA
| | - Anneka Ehrnst
- Department of Laboratory Medicine, Division of Clinical Virology, Karolinska University Hospital Huddinge, Karolinska Institutet, Box 280, SE-171 77 Stockholm, Sweden
- Microbiology and Tumor Biology Center, Karolinska Institutet, Box 280, SE-171 77 Stockholm, Sweden
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45
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Dong HF, Wigmore K, Carrington MN, Dean M, Turpin JA, Howard OMZ. Variants of CCR5, which are permissive for HIV-1 infection, show distinct functional responses to CCL3, CCL4 and CCL5. Genes Immun 2005; 6:609-19. [PMID: 16015368 PMCID: PMC1369982 DOI: 10.1038/sj.gene.6364247] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
CCR5 is one of the primary coreceptors for Env-mediated fusion between cells and human immunodeficiency virus type 1 (HIV-1). Analyses of CCR5 variants in cohorts of HIV-1 high-risk individuals led to the identification of multiple single amino-acid substitutions, which may have functional consequences. This study focused on eight naturally occurring allelic variants located between amino-acid residues 60 and 334 of CCR5. All studied allelic variants were highly expressed on the cell surface of HEK-293 cells and permissive for HIV-1 infection. Variant G301V showed 3.5-fold increase in 50% effective concentration (EC(50)) for CCL4 (MIP 1beta) in a competitive binding assay. There was also a significant reduction in CCL5 (RANTES) EC(50) for the R223Q, A335V and Y339F variants. The most unexpected functional abnormality was exhibited by the R60S variant that exhibited a loss of ligand-induced desensitization in chemotaxis assays, but showed normal CCL4 and CCL5 binding avidity. This mutation is located in the first intracellular loop, a domain that has not previously been shown to be involved in receptor desensitization. In conclusion, our results support earlier studies showing that these naturally occurring point mutations do not limit HIV-1 infection, and indicated that single amino-acid changes can have unexpected functional consequences.
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Affiliation(s)
- H-F Dong
- Basic Research Program, SAIC Frederick, Bethesda, MD, USA
| | - K Wigmore
- Basic Research Program, SAIC Frederick, Bethesda, MD, USA
| | - MN Carrington
- Basic Research Program, SAIC Frederick, Bethesda, MD, USA
| | - M Dean
- National Cancer Institute (NCI) Center for Cancer Research (CCR) Laboratory of Genomic Diversity, Bethesda MD, USA
| | - JA Turpin
- Southern Research Institute, Bethesda MD, USA
| | - OMZ Howard
- NCI/CCR/Laboratory of Molecular Immunoregulation, NCI-Frederick, Frederick, MD, USA
- Correspondence: Dr OMZ Howard, NCI/CCR/Laboratory of Molecular Immunoregulation, NCI-Frederick, PO Box B, 1050 Boyles Street, Frederick, MD 21702, USA. E-mail:
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46
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Coil DA, Miller AD. Phosphatidylserine treatment relieves the block to retrovirus infection of cells expressing glycosylated virus receptors. Retrovirology 2005; 2:49. [PMID: 16091143 PMCID: PMC1201173 DOI: 10.1186/1742-4690-2-49] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2005] [Accepted: 08/09/2005] [Indexed: 01/13/2023] Open
Abstract
Background A major determinant of retrovirus host range is the presence or absence of appropriate cell-surface receptors required for virus entry. Often orthologs of functional receptors are present in a wide range of species, but amino acid differences can render these receptors non-functional. In some cases amino acid differences result in additional N-linked glycosylation that blocks virus infection. The latter block to retrovirus infection can be overcome by treatment of cells with compounds such as tunicamycin, which prevent the addition of N-linked oligosaccharides. Results We have discovered that treatment of cells with liposomes composed of phosphatidylserine (PS) can also overcome the block to infection mediated by N-linked glycosylation. Importantly, this effect occurs without apparent change in the glycosylation state of the receptors for these viruses. This effect occurs with delayed kinetics compared to previous results showing enhancement of virus infection by PS treatment of cells expressing functional virus receptors. Conclusion We have demonstrated that PS treatment can relieve the block to retrovirus infection of cells expressing retroviral receptors that have been rendered non-functional by glycosylation. These findings have important implications for the current model describing inhibition of virus entry by receptor glycosylation.
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Affiliation(s)
- David A Coil
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109-1024 USA
- Molecular and Cellular Biology Program, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109-1024 USA
| | - A Dusty Miller
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109-1024 USA
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47
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Sloane AJ, Raso V, Dimitrov DS, Xiao X, Deo S, Muljadi N, Restuccia D, Turville S, Kearney C, Broder CC, Zoellner H, Cunningham AL, Bendall L, Lynch GW. Marked structural and functional heterogeneity in CXCR4: separation of HIV-1 and SDF-1alpha responses. Immunol Cell Biol 2005; 83:129-43. [PMID: 15748209 DOI: 10.1111/j.1440-1711.2004.01304.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
CXCR4, the chemotactic cell receptor for SDF-1alpha, is essential for immune trafficking and HIV infection. CXCR4 is remarkably heterogeneous and the purpose of this study was to better identify the isoforms expressed by cells and compare their structure and function. We found that cells express either a predominant isoform or multiple isoforms. These were best resolved on SDS-PAGE using sucrose-gradient-fractionated, triton-insoluble, membrane extracts. We hypothesized that glycosyl modification may underpin some of this heterogeneity and that cell isoform(s) differences may underscore CXCR4's multiple cell functions. A comparison of wild-type (WT) and dual N-linked glycosylation site, N11A/N176A, mutant CXCR4 expressed in 3T3 and HEK-293 cells served to implicate variabilities in glycosylation and oligomerization in almost half of the isoforms. Immunoprecipitation of CXCR4 revealed monomer and dimer non-glycosylated forms of 34 kDa and 68 kDa from the N11A/N176A mutant, compared with glycosylated 40 kDa and 47 kDa and 73 kDa and 80 kDa forms from WT. The functional specificity of isoform action was also implicated because, despite CEMT4 cells expressing high levels of CXCR4 and 11 different isoforms, a single 83 kDa form was found to bind gp120 for HIV-1 IIIB infection. Furthermore, comparative studies found that in contrast to SDF-1alpha-responsive Nalm-6 cells that expressed similar levels of a single isoform, CEMT4 cells did not show a Ca(++) flux or a chemotactic response to SDF-1alpha. Thus, CXCR4 can differ both structurally and functionally between cells, with HIV-1 infection and chemotaxis apparently mediated by different isoforms. This separation of structure and function has implications for understanding HIV-1 entry and SDF-1alpha responses and may indicate therapeutic possibilities.
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Affiliation(s)
- Andrew J Sloane
- HIV-Protein Interactions Laboratory, Centre for Virus Research, Westmead, NSW, Australia
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48
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Neel NF, Schutyser E, Sai J, Fan GH, Richmond A. Chemokine receptor internalization and intracellular trafficking. Cytokine Growth Factor Rev 2005; 16:637-58. [PMID: 15998596 PMCID: PMC2668263 DOI: 10.1016/j.cytogfr.2005.05.008] [Citation(s) in RCA: 172] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2005] [Accepted: 05/03/2005] [Indexed: 01/25/2023]
Abstract
The internalization and intracellular trafficking of chemokine receptors have important implications for the cellular responses elicited by chemokine receptors. The major pathway by which chemokine receptors internalize is the clathrin-mediated pathway, but some receptors may utilize lipid rafts/caveolae-dependent internalization routes. This review discusses the current knowledge and controversies regarding these two different routes of endocytosis. The functional consequences of internalization and the regulation of chemokine receptor recycling will also be addressed. Modifications of chemokine receptors, such as palmitoylation, ubiquitination, glycosylation, and sulfation, may also impact trafficking, chemotaxis and signaling. Finally, this review will cover the internalization and trafficking of viral and decoy chemokine receptors.
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Affiliation(s)
- Nicole F Neel
- Department of Veterans Affairs Medical Center, Vanderbilt University School of Medicine, 432 PRB, 23rd Avenue South at Pierce, Nashville, TN 37232, USA.
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49
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Conti L, Fantuzzi L, Del Cornò M, Belardelli F, Gessani S. Immunomodulatory effects of the HIV-1 gp120 protein on antigen presenting cells: implications for AIDS pathogenesis. Immunobiology 2005; 209:99-115. [PMID: 15481145 DOI: 10.1016/j.imbio.2004.02.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Antigen presenting cell (APC) function is central to the development of an effective anti-viral immune response. Among APC, monocytes, macrophages and dendritic cells (DC) form the principal non-T cell compartment involved in in vivo HIV infection, and these cells play important and well-established roles in multiple aspects of viral pathogenesis. HIV infection may result in APC defects, which could ultimately contribute to the loss of CD4+ T cell responses observed early in HIV infection, when the CD4+ T cell number is still within the normal range. Extensive in vitro studies have demonstrated that the envelope glycoproteins of HIV-1 exert profound influences on various cell populations of the immune system, including hematopoietic progenitors, T and B lymphocytes, monocytes/ macrophages and DC, as well as on neuronal cells. The demonstration of the presence of envelope proteins both free in the circulation and bound to the surface of CD4+ cells suggests that gp120 interactions with non-infected cells can influence cellular functions in vivo, thus contributing to the immunopathogenesis of AIDS. This paper provides an overview of the present knowledge on gp120 binding, signal transduction triggering and interference with macrophage and DC functions and it highlights the importance of this interaction in the pathogenesis of AIDS.
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Affiliation(s)
- Lucia Conti
- Department of Cell Biology and Neurosciences, Istituto Superiore di Sanità, Viale Regina Elena, 299, Rome 00161, Italy
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50
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Platt EJ, Shea DM, Rose PP, Kabat D. Variants of human immunodeficiency virus type 1 that efficiently use CCR5 lacking the tyrosine-sulfated amino terminus have adaptive mutations in gp120, including loss of a functional N-glycan. J Virol 2005; 79:4357-68. [PMID: 15767436 PMCID: PMC1061536 DOI: 10.1128/jvi.79.7.4357-4368.2005] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
By selecting the R5 human immunodeficiency virus type 1 (HIV-1) strain JR-CSF for efficient use of a CCR5 coreceptor with a badly damaged amino terminus [i.e., CCR5(Y14N)], we previously isolated variants that weakly utilize CCR5(Delta18), a low-affinity mutant lacking the normal tyrosine sulfate-containing amino-terminal region of the coreceptor. These previously isolated HIV-1(JR-CSF) variants contained adaptive mutations situated exclusively in the V3 loop of their gp120 envelope glycoproteins. We now have weaned the virus from all dependency on the CCR5 amino terminus by performing additional selections with HeLa-CD4 cells that express only a low concentration of CCR5(Delta18). The adapted variants had additional mutations in their V3 loops, as well as one in the V2 stem (S193N) and four alternative mutations in the V4 loop that eliminated the same N-linked oligosaccharide from position N403. Assays using pseudotyped viruses suggested that these new gp120 mutations all made strong contributions to use of CCR5(Delta18) by accelerating a rate-limiting CCR5-dependent conformational change in gp41 rather than by increasing viral affinity for this damaged coreceptor. Consistent with this interpretation, loss of the V4 N-glycan at position N403 also enhanced HIV-1 use of a different low-affinity CCR5 coreceptor with a mutation in extracellular loop 2 (ECL2) [i.e., CCR5(G163R)], whereas the double mutant CCR5(Delta18,G163R) was inactive. We conclude that loss of the N-glycan at position N403 helps to convert the HIV-1 envelope into a hair-trigger form that no longer requires strong interactions with both the CCR5 amino terminus and ECL2 but efficiently uses either site alone. These results demonstrate a novel functional role for a gp120 N-linked oligosaccharide and a high degree of adaptability in coreceptor usage by HIV-1.
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Affiliation(s)
- Emily J Platt
- Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, OR 97239-3098, USA
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