1
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Crine SL, Acharya KR. Molecular basis of C-mannosylation - a structural perspective. FEBS J 2022; 289:7670-7687. [PMID: 34741587 DOI: 10.1111/febs.16265] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Revised: 10/22/2021] [Accepted: 11/04/2021] [Indexed: 01/14/2023]
Abstract
The structural and functional diversity of proteins can be enhanced by numerous post-translational modifications. C-mannosylation is a rare form of glycosylation consisting of a single alpha or beta D-mannopyranose forming a carbon-carbon bond with the pyrrole ring of a tryptophan residue. Despite first being discovered in 1994, C-mannosylation is still poorly understood and 3D structures are available for only a fraction of the total predicted C-mannosylated proteins. Here, we present the first comprehensive review of C-mannosylated protein structures by analysing the data for all 10 proteins with C-mannosylation/s deposited in the Research Collaboratory for Structural Bioinformatics Protein Data Bank (RCSB PDB). We analysed in detail the WXXW/WXXWXXW consensus motif and the highly conserved pair of arginine residues in thrombospondin type 1 repeat C-mannosylation sites or homologous arginine residues in other domains. Furthermore, we identified a conserved PXP sequence C-terminal of the C-mannosylation site. The PXP motif forms a tight turn region in the polypeptide chain and its universal conservation in C-mannosylated protein is worthy of further experimental study. The stabilization of C-mannopyranosyl groups was demonstrated through hydrogen bonding with arginine and other charged or polar amino acids. Where possible, the structural findings were linked to other functional studies demonstrating the role of C-mannosylation in protein stability, secretion or function. With the current technological advances in structural biology, we hope to see more progress in the study of C-mannosylation that may correspond to discoveries of novel C-mannosylation pathways and functions with implications for human health and biotechnology.
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Affiliation(s)
- Samuel L Crine
- Department of Biology and Biochemistry, University of Bath, UK
| | - K Ravi Acharya
- Department of Biology and Biochemistry, University of Bath, UK
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2
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Nishitsuji K, Ikezaki M, Manabe S, Uchimura K, Ito Y, Ihara Y. Thrombospondin type 1 repeat-derived C-mannosylated peptide attenuates synaptogenesis of cortical neurons induced by primary astrocytes via TGF-β. Glycoconj J 2021; 39:701-710. [PMID: 34791612 DOI: 10.1007/s10719-021-10030-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 10/07/2021] [Accepted: 11/09/2021] [Indexed: 10/19/2022]
Abstract
C-Mannosylation is a rare type of protein glycosylation and is reportedly critical for the proper folding and secretion of parental proteins. Still, the effects of C-mannosylation on the biological functions of these modified proteins remain to be elucidated. The Trp-x-x-Trp (WxxW) sequences, whose first tryptophan (Trp) can be C-mannosylated, constitute the consensus motifs for this glycosylation modification and are commonly found in thrombospondin type 1 repeats that regulate molecular functions of thrombospondin 1 in binding and activation of transforming growth factor β (TGF-β). TGF-β plays critical roles in the control of the central nervous system including synaptogenesis. Here, we investigated whether C-mannosylation of the synthetic Trp-Ser-Pro-Trp (WSPW) peptide may confer certain functions to this peptide in TGF-β-mediated synaptogenesis. By using primary cultured rat astrocytes and cortical neurons, we found that the C-mannosylated WSPW (C-Man-WSPW) peptide, but not non-mannosylated WSPW peptide, suppressed astrocyte-conditioned medium (ACM)-stimulated synaptogenesis. C-Man-WSPW peptide inhibited both ACM- and recombinant mature TGF-β1-induced activations of Smad 2, an important mediator in TGF-β signaling. Interactions of recombinant mature TGF-β with the C-Man-WSPW peptide were similar to those with non-C-mannosylated WSPW peptide. Taken together, our results reveal a novel function of C-mannosylation of the WxxW motif in signaling and synaptogenesis mediated by TGF-β. Molecular details of how C-mannosylation affects the biological functions of WxxW motifs deserve future study for clarification.
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Affiliation(s)
- Kazuchika Nishitsuji
- Department of Biochemistry, Wakayama Medical University, Wakayama, 641-8509, Japan.
| | - Midori Ikezaki
- Department of Biochemistry, Wakayama Medical University, Wakayama, 641-8509, Japan
| | - Shino Manabe
- Laboratory of Functional Molecule Chemistry, Pharmaceutical Department and Institute of Medicinal Chemistry, Hoshi University, Tokyo, 142-8501, Japan.,Research Center for Pharmaceutical Development, Graduate School of Pharmaceutical Sciences & Faculty of Pharmaceutical Sciences, Tohoku University, Miyagi, 980-8578, Japan
| | - Kenji Uchimura
- Unité de Glycobiologie Structurale Et Fonctionnelle, UMR 8576, CNRS, Université de Lille, 59655, Villeneuve d'Ascq, France
| | - Yukishige Ito
- RIKEN Cluster for Pioneering Research, Saitama, 351-0198, Japan.,Graduate School of Science, Osaka University, Osaka, 560-0043, Japan
| | - Yoshito Ihara
- Department of Biochemistry, Wakayama Medical University, Wakayama, 641-8509, Japan.
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3
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Ikezaki M, Nishitsuji K, Matsumura K, Manabe S, Shibukawa Y, Wada Y, Ito Y, Ihara Y. C-Mannosylated tryptophan-containing WSPW peptide binds to actinin-4 and alters E-cadherin subcellular localization in lung epithelial-like A549 cells. Biochimie 2021; 192:136-146. [PMID: 34673139 DOI: 10.1016/j.biochi.2021.10.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 10/08/2021] [Accepted: 10/14/2021] [Indexed: 11/18/2022]
Abstract
The Trp-x-x-Trp (W-x-x-W) peptide motif, a consensus site for C-mannosylation, is the functional motif in cytokine type I receptors or thrombospondin type I repeat (TSR) superfamily proteins. W-x-x-W motifs are important for physiological and pathological functions of their parental proteins, but effects of C-mannosylation on protein functions remain to be elucidated. By using chemically synthesized WSPW peptides and C-mannosylated WSPW peptides (C-Man-WSPW), we herein investigated whether C-mannosylation of WSPW peptides confer additional biological functions to WSPW peptides. C-Man-WSPW peptide, but not non-mannosylated WSPW, reduced E-cadherin levels in A549 cells. Via peptide mass fingerprinting analysis, we identified actinin-4 as a C-Man-WSPW-binding protein in A549 cells. Actinin-4 partly co-localized with E-cadherin or β-catenin, despite no direct interaction between actinin-4 and E-cadherin. C-Man-WSPW reduced co-localization of E-cadherin and actinin-4; non-mannosylated WSPW had no effect on localization. In actinin-4-knockdown cells, E-cadherin was upregulated and demonstrated a punctate staining pattern in the cytoplasm, which suggests that actinin-4 regulated cell-surface E-cadherin localization. Thus, C-mannosylation of WSPW peptides is required for interaction with actinin-4 that subsequently alters expression and subcellular localization of E-cadherin and morphology of epithelial-like cells. Our results therefore suggest a regulatory role of C-mannosylation of the W-x-x-W motif in interactions between the motif and its binding partner and will thereby enhance understanding of protein C-mannosylation.
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Affiliation(s)
- Midori Ikezaki
- Department of Biochemistry, School of Medicine, Wakayama Medical University, Wakayama, 641-8509, Japan
| | - Kazuchika Nishitsuji
- Department of Biochemistry, School of Medicine, Wakayama Medical University, Wakayama, 641-8509, Japan.
| | - Ko Matsumura
- Department of Biochemistry, School of Medicine, Wakayama Medical University, Wakayama, 641-8509, Japan
| | - Shino Manabe
- Laboratory of Functional Molecule Chemistry, Pharmaceutical Department and Institute of Medicinal Chemistry, Hoshi University, Tokyo, 142-8501, Japan; Research Center for Pharmaceutical Development, Graduate School of Pharmaceutical Sciences & Faculty of Pharmaceutical Sciences, Tohoku University, Miyagi, 980-8578, Japan
| | - Yukinao Shibukawa
- Department of Molecular Medicine, Osaka Medical Center and Research Institute for Maternal and Child Health, Osaka, 594-1101, Japan
| | - Yoshinao Wada
- Department of Molecular Medicine, Osaka Medical Center and Research Institute for Maternal and Child Health, Osaka, 594-1101, Japan
| | - Yukishige Ito
- RIKEN Cluster for Pioneering Research, Saitama, 351-0198, Japan; Graduate School of Science, Osaka University, Osaka, 560-0043, Japan
| | - Yoshito Ihara
- Department of Biochemistry, School of Medicine, Wakayama Medical University, Wakayama, 641-8509, Japan.
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4
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Minakata S, Manabe S, Inai Y, Ikezaki M, Nishitsuji K, Ito Y, Ihara Y. Protein C-Mannosylation and C-Mannosyl Tryptophan in Chemical Biology and Medicine. Molecules 2021; 26:molecules26175258. [PMID: 34500691 PMCID: PMC8433626 DOI: 10.3390/molecules26175258] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 08/25/2021] [Accepted: 08/26/2021] [Indexed: 12/25/2022] Open
Abstract
C-Mannosylation is a post-translational modification of proteins in the endoplasmic reticulum. Monomeric α-mannose is attached to specific Trp residues at the first Trp in the Trp-x-x-Trp/Cys (W-x-x-W/C) motif of substrate proteins, by the action of C-mannosyltransferases, DPY19-related gene products. The acceptor substrate proteins are included in the thrombospondin type I repeat (TSR) superfamily, cytokine receptor type I family, and others. Previous studies demonstrated that C-mannosylation plays critical roles in the folding, sorting, and/or secretion of substrate proteins. A C-mannosylation-defective gene mutation was identified in humans as the disease-associated variant affecting a C-mannosylation motif of W-x-x-W of ADAMTSL1, which suggests the involvement of defects in protein C-mannosylation in human diseases such as developmental glaucoma, myopia, and/or retinal defects. On the other hand, monomeric C-mannosyl Trp (C-Man-Trp), a deduced degradation product of C-mannosylated proteins, occurs in cells and extracellular fluids. Several studies showed that the level of C-Man-Trp is upregulated in blood of patients with renal dysfunction, suggesting that the metabolism of C-Man-Trp may be involved in human kidney diseases. Together, protein C-mannosylation is considered to play important roles in the biosynthesis and functions of substrate proteins, and the altered regulation of protein C-manosylation may be involved in the pathophysiology of human diseases. In this review, we consider the biochemical and biomedical knowledge of protein C-mannosylation and C-Man-Trp, and introduce recent studies concerning their significance in biology and medicine.
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Affiliation(s)
- Shiho Minakata
- Department of Biochemistry, Wakayama Medical University, 811-1 Kimiidera, Wakayama, Wakayama 641-0012, Japan; (S.M.); (Y.I.); (M.I.); (K.N.)
| | - Shino Manabe
- Pharmaceutical Department, The Institute of Medicinal Chemistry, Hoshi University, 2-4-41 Ebara, Shinagawa, Tokyo 142-8501, Japan;
- Research Center for Pharmaceutical Development, Graduate School of Pharmaceutical Science & Faculty of Pharmaceutical Sciences, Tohoku University, 6-3 Aoba, Sendai, Miyagi 980-8578, Japan
| | - Yoko Inai
- Department of Biochemistry, Wakayama Medical University, 811-1 Kimiidera, Wakayama, Wakayama 641-0012, Japan; (S.M.); (Y.I.); (M.I.); (K.N.)
| | - Midori Ikezaki
- Department of Biochemistry, Wakayama Medical University, 811-1 Kimiidera, Wakayama, Wakayama 641-0012, Japan; (S.M.); (Y.I.); (M.I.); (K.N.)
| | - Kazuchika Nishitsuji
- Department of Biochemistry, Wakayama Medical University, 811-1 Kimiidera, Wakayama, Wakayama 641-0012, Japan; (S.M.); (Y.I.); (M.I.); (K.N.)
| | - Yukishige Ito
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka 560-0043, Japan;
- RIKEN Cluster for Pioneering Research, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Yoshito Ihara
- Department of Biochemistry, Wakayama Medical University, 811-1 Kimiidera, Wakayama, Wakayama 641-0012, Japan; (S.M.); (Y.I.); (M.I.); (K.N.)
- Correspondence: ; Tel.: +81-73-441-0628
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5
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Roy A, Shrivastva S, Naseer S. In and out: Traffic and dynamics of thrombopoietin receptor. J Cell Mol Med 2021; 25:9073-9083. [PMID: 34448528 PMCID: PMC8500957 DOI: 10.1111/jcmm.16878] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 07/27/2021] [Accepted: 08/04/2021] [Indexed: 12/17/2022] Open
Abstract
Thrombopoiesis had long been a challenging area of study due to the rarity of megakaryocyte precursors in the bone marrow and the incomplete understanding of its regulatory cytokines. A breakthrough was achieved in the early 1990s with the discovery of the thrombopoietin receptor (TpoR) and its ligand thrombopoietin (TPO). This accelerated research in thrombopoiesis, including the uncovering of the molecular basis of myeloproliferative neoplasms (MPN) and the advent of drugs to treat thrombocytopenic purpura. TpoR mutations affecting its membrane dynamics or transport were increasingly associated with pathologies such as MPN and thrombocytosis. It also became apparent that TpoR affected hematopoietic stem cell (HSC) quiescence while priming hematopoietic stem cells (HSCs) towards the megakaryocyte lineage. Thorough knowledge of TpoR surface localization, dimerization, dynamics and stability is therefore crucial to understanding thrombopoiesis and related pathologies. In this review, we will discuss the mechanisms of TpoR traffic. We will focus on the recent progress in TpoR membrane dynamics and highlight the areas that remain unexplored.
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Affiliation(s)
- Anita Roy
- Kusuma School of Biological Sciences, Indian Institute of Technology, New Delhi, India
| | - Saurabh Shrivastva
- Kusuma School of Biological Sciences, Indian Institute of Technology, New Delhi, India
| | - Saadia Naseer
- Kusuma School of Biological Sciences, Indian Institute of Technology, New Delhi, India
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6
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Cirksena K, Hütte HJ, Shcherbakova A, Thumberger T, Sakson R, Weiss S, Jensen LR, Friedrich A, Todt D, Kuss AW, Ruppert T, Wittbrodt J, Bakker H, Buettner FFR. The C-Mannosylome of Human Induced Pluripotent Stem Cells Implies a Role for ADAMTS16 C-Mannosylation in Eye Development. Mol Cell Proteomics 2021; 20:100092. [PMID: 33975020 PMCID: PMC8256286 DOI: 10.1016/j.mcpro.2021.100092] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 04/22/2021] [Accepted: 05/04/2021] [Indexed: 12/11/2022] Open
Abstract
C-mannosylation is a modification of tryptophan residues with a single mannose and can affect protein folding, secretion, and/or function. To date, only a few proteins have been demonstrated to be C-mannosylated, and studies that globally assess protein C-mannosylation are scarce. To interrogate the C-mannosylome of human induced pluripotent stem cells, we compared the secretomes of CRISPR–Cas9 mutants lacking either the C-mannosyltransferase DPY19L1 or DPY19L3 to WT human induced pluripotent stem cells using MS-based quantitative proteomics. The secretion of numerous proteins was reduced in these mutants, including that of A Disintegrin And Metalloproteinase with ThromboSpondin Motifs 16 (ADAMTS16), an extracellular protease that was previously reported to be essential for optic fissure fusion in zebrafish eye development. To test the functional relevance of this observation, we targeted dpy19l1 or dpy19l3 in embryos of the Japanese rice fish medaka (Oryzias latipes) by CRISPR–Cas9. We observed that targeting of dpy19l3 partially caused defects in optic fissure fusion, called coloboma. We further showed in a cellular model that DPY19L1 and DPY19L3 mediate C-mannosylation of a recombinantly expressed thrombospondin type 1 repeat of ADAMTS16 and thereby support its secretion. Taken together, our findings imply that DPY19L3-mediated C-mannosylation is involved in eye development by assisting secretion of the extracellular protease ADAMTS16. TSR1 of ADAMTS16 can be C-mannosylated. Deletion of DPY19L1 or DPY19L3 in hiPSCs caused reduced secretion of ADAMTS16. Targeting of dpy19l3 in medaka occasionally led to coloboma.
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Affiliation(s)
- Karsten Cirksena
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Hermann J Hütte
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | | | - Thomas Thumberger
- Centre for Organismal Studies Heidelberg, Heidelberg University, Heidelberg, Germany
| | - Roman Sakson
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH), DKFZ-ZMBH Alliance, Heidelberg, Germany; HBIGS, Heidelberg Biosciences International Graduate School, Heidelberg University, Heidelberg, Germany; Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V., Dortmund, Germany
| | - Stefan Weiss
- Human Molecular Genetics Group, Department of Functional Genomics, Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Germany
| | - Lars Riff Jensen
- Human Molecular Genetics Group, Department of Functional Genomics, Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Germany
| | - Alina Friedrich
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Daniel Todt
- Department for Molecular and Medical Virology, Ruhr University Bochum, Bochum, Germany; European Virus Bioinformatics Center (EVBC), Jena, Germany
| | - Andreas W Kuss
- Human Molecular Genetics Group, Department of Functional Genomics, Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald, Greifswald, Germany
| | - Thomas Ruppert
- Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH), DKFZ-ZMBH Alliance, Heidelberg, Germany
| | - Joachim Wittbrodt
- Centre for Organismal Studies Heidelberg, Heidelberg University, Heidelberg, Germany
| | - Hans Bakker
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Falk F R Buettner
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany.
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7
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Monomeric C-mannosyl tryptophan is a degradation product of autophagy in cultured cells. Glycoconj J 2020; 37:635-645. [PMID: 32803368 DOI: 10.1007/s10719-020-09938-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2019] [Revised: 07/30/2020] [Accepted: 08/06/2020] [Indexed: 12/14/2022]
Abstract
C-Mannosyl tryptophan (C-Man-Trp) is a unique glycosylated amino acid present in various eukaryotes. The C-Man-Trp structure can be found as a monomeric form or a part of post-translational modifications within polypeptide chains in living organisms. However, the mechanism of how monomeric C-Man-Trp is produced has not been fully investigated. In this study, we assessed levels of cellular C-Man-Trp by ultra performance liquid chromatography with a mass spectrometry assay system, and investigated whether the cellular C-Man-Trp is affected by autophagy induction. The intracellular C-Man-Trp level was significantly increased under serum and/or amino acid starvation in A549, HaCaT, HepG2, NIH3T3, and NRK49F cells. The increase in C-Man-Trp was also observed in NIH3T3 cells treated with rapamycin, an autophagy inducer. The up-regulation of C-Man-Trp caused by starvation was reversed by the inhibition of lysosomal enzymes. We further showed that C-Man-Trp is produced by incubating a synthetic C-mannosylated peptide (C-Man-Trp-Ser-Pro-Trp) or thrombospondin (TSP) in a lysosomal fraction that was prepared from a mouse liver, which provides supporting evidence that C-Man-Trp is a degradation product of the C-mannosylated peptide or protein following lysosome-related proteolysis. Taken together, we propose that the autophagic pathway is a novel pathway that at least partly contributes to intracellular C-Man-Trp production under certain conditions, such as nutrient starvation.
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8
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Metcalfe RD, Putoczki TL, Griffin MDW. Structural Understanding of Interleukin 6 Family Cytokine Signaling and Targeted Therapies: Focus on Interleukin 11. Front Immunol 2020; 11:1424. [PMID: 32765502 PMCID: PMC7378365 DOI: 10.3389/fimmu.2020.01424] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 06/02/2020] [Indexed: 12/12/2022] Open
Abstract
Cytokines are small signaling proteins that have central roles in inflammation and cell survival. In the half-century since the discovery of the first cytokines, the interferons, over fifty cytokines have been identified. Amongst these is interleukin (IL)-6, the first and prototypical member of the IL-6 family of cytokines, nearly all of which utilize the common signaling receptor, gp130. In the last decade, there have been numerous advances in our understanding of the structural mechanisms of IL-6 family signaling, particularly for IL-6 itself. However, our understanding of the detailed structural mechanisms underlying signaling by most IL-6 family members remains limited. With the emergence of new roles for IL-6 family cytokines in disease and, in particular, roles of IL-11 in cardiovascular disease, lung disease, and cancer, there is an emerging need to develop therapeutics that can progress to clinical use. Here we outline our current knowledge of the structural mechanism of signaling by the IL-6 family of cytokines. We discuss how this knowledge allows us to understand the mechanism of action of currently available inhibitors targeting IL-6 family cytokine signaling, and most importantly how it allows for improved opportunities to pharmacologically disrupt cytokine signaling. We focus specifically on the need to develop and understand inhibitors that disrupt IL-11 signaling.
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Affiliation(s)
- Riley D Metcalfe
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Technology Institute, The University of Melbourne, Parkville, VIC, Australia
| | - Tracy L Putoczki
- Personalised Oncology Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia.,Department of Medical Biology, The University of Melbourne, Parkville, VIC, Australia
| | - Michael D W Griffin
- Department of Biochemistry and Molecular Biology, Bio21 Molecular Science and Technology Institute, The University of Melbourne, Parkville, VIC, Australia
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9
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Shcherbakova A, Preller M, Taft MH, Pujols J, Ventura S, Tiemann B, Buettner FF, Bakker H. C-mannosylation supports folding and enhances stability of thrombospondin repeats. eLife 2019; 8:52978. [PMID: 31868591 PMCID: PMC6954052 DOI: 10.7554/elife.52978] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Accepted: 12/22/2019] [Indexed: 12/12/2022] Open
Abstract
Previous studies demonstrated importance of C-mannosylation for efficient protein secretion. To study its impact on protein folding and stability, we analyzed both C-mannosylated and non-C-mannosylated thrombospondin type 1 repeats (TSRs) of netrin receptor UNC-5. In absence of C-mannosylation, UNC-5 TSRs could only be obtained at low temperature and a significant proportion displayed incorrect intermolecular disulfide bridging, which was hardly observed when C-mannosylated. Glycosylated TSRs exhibited higher resistance to thermal and reductive denaturation processes, and the presence of C-mannoses promoted the oxidative folding of a reduced and denatured TSR in vitro. Molecular dynamics simulations supported the experimental studies and showed that C-mannoses can be involved in intramolecular hydrogen bonding and limit the flexibility of the TSR tryptophan-arginine ladder. We propose that in the endoplasmic reticulum folding process, C-mannoses orient the underlying tryptophan residues and facilitate the formation of the tryptophan-arginine ladder, thereby influencing the positioning of cysteines and disulfide bridging.
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Affiliation(s)
| | - Matthias Preller
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Manuel H Taft
- Institute for Biophysical Chemistry, Hannover Medical School, Hannover, Germany
| | - Jordi Pujols
- Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Salvador Ventura
- Institut de Biotecnologia i Biomedicina, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Birgit Tiemann
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Falk Fr Buettner
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
| | - Hans Bakker
- Institute of Clinical Biochemistry, Hannover Medical School, Hannover, Germany
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10
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Semlali A, Almutairi M, Azzi A, Reddy Parine N, AlAmri A, Alsulami S, Meshal Alumri T, Saud Alanazi M, Rouabhia M. TSLP and TSLP receptors variants are associated with smoking. Mol Genet Genomic Med 2019; 7:e842. [PMID: 31290290 PMCID: PMC6687645 DOI: 10.1002/mgg3.842] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 05/21/2019] [Accepted: 05/31/2019] [Indexed: 12/18/2022] Open
Abstract
Background To search for new prevention markers for early detection of the diseases caused by tobacco, we aimed to investigate the polymorphisms in TSLP and TSLPRs associated with cigarette smoking in the Saudi population. Materials and methods Samples were collected from 177 smokers and 126 healthy controls. Three TSLP SNPs [rs3806933, rs2289276, and rs10043985], three TSLPR SNPs [rs36133495, rs36177645, and rs36139698], and two IL7R SNPs rs1053496 and rs12516866 were analyzed by genotyping. Results Two TSLP SNPs (rs10043985 and rs3806933) and one TSLPR SNP (rs36139698) showed significant correlations with smoking behavior, but not IL7R rs12516866 and rs1053496. rs10043985 showed a clear association with long‐term smoking regardless of daily cigarette consumption. rs2289276 was associated with short‐term smoking but not with daily cigarette consumption. rs3806933 was highly associated with different smoker subgroups. Rs36139698 was highly associated with long‐term smokers who consumed ≥20 cigarettes/day, and the “T” allele was associated only with individuals who smoked ≤20 cigarettes/day. Rs36139698 corresponds to a P195L substitution and produces a TSLPR mutant with a predicted ΔΔG increase of 2.15 kcal/mol and has a more stable structure than the wild‐type variant. Conclusions Investigating TSLP and TSLPR polymorphisms is crucial for elucidating the mechanisms underlying tobacco‐induced diseases.
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Affiliation(s)
- Abdelhabib Semlali
- Groupe de Recherche en Écologie Buccale, Département de stomatologie, Faculté de Médecine Dentaire, Université Laval, Québec, Québec, Canada.,Department of Biochemistry, College of Science King Saud University, Riyadh, Kingdom of Saudi Arabia
| | - Mikhlid Almutairi
- Zoology Department, College of Science King Saud University, Riyadh, Kingdom of Saudi Arabia
| | - Arezki Azzi
- Department of Biochemistry, College of Medicine, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh, Kingdom of Saudi Arabia
| | - Narasimha Reddy Parine
- Department of Biochemistry, College of Science King Saud University, Riyadh, Kingdom of Saudi Arabia
| | - Abdullah AlAmri
- Department of Biochemistry, College of Science King Saud University, Riyadh, Kingdom of Saudi Arabia
| | - Saleh Alsulami
- Department of Biochemistry, College of Medicine, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh, Kingdom of Saudi Arabia
| | - Talal Meshal Alumri
- Department of Biochemistry, College of Medicine, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh, Kingdom of Saudi Arabia
| | - Mohammad Saud Alanazi
- Department of Biochemistry, College of Science King Saud University, Riyadh, Kingdom of Saudi Arabia
| | - Mahmoud Rouabhia
- Groupe de Recherche en Écologie Buccale, Département de stomatologie, Faculté de Médecine Dentaire, Université Laval, Québec, Québec, Canada
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11
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Fernandez IZ, Baxter RM, Garcia-Perez JE, Vendrame E, Ranganath T, Kong DS, Lundquist K, Nguyen T, Ogolla S, Black J, Galambos C, Gumbart JC, Dawany N, Kelsen JR, de Zoeten EF, Quinones R, Eissa H, Verneris MR, Sullivan KE, Rochford R, Blish CA, Kedl RM, Dutmer CM, Hsieh EWY. A novel human IL2RB mutation results in T and NK cell-driven immune dysregulation. J Exp Med 2019; 216:1255-1267. [PMID: 31040184 PMCID: PMC6547857 DOI: 10.1084/jem.20182015] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 02/24/2019] [Accepted: 04/04/2019] [Indexed: 11/13/2022] Open
Abstract
A novel homozygous mutation in human IL2RB results in decreased IL-2Rβ protein expression and dysregulated IL-2/15 signaling. This hypomorphic mutation leads to decreased regulatory T cell frequency and an abnormal NK cell compartment, with clinical manifestations of autoimmunity and susceptibility to CMV. The pleiotropic actions of interleukin-2 (IL-2) are essential for regulation of immune responses and maintenance of immune tolerance. The IL-2 receptor (IL-2R) is composed of IL-2Rα, IL-2Rβ, and IL-2Rγ subunits, with defects in IL-2Rα and IL-2Rγ and their downstream signaling effectors resulting in known primary immunodeficiency disorders. Here, we report the first human defect in IL-2Rβ, occurring in two infant siblings with a homozygous IL2RB mutation in the WSXWS motif, manifesting as multisystem autoimmunity and susceptibility to CMV infection. The hypomorphic mutation results in diminished IL-2Rβ surface expression and dysregulated IL-2/15 signaling, with an anticipated reduction in regulatory T cells. However, in contrast to the IL-2Rβ−/− animal model, which lacks NK cells, these siblings demonstrate an expansion of NK cells, particularly the CD56bright subset, and a lack of terminally differentiated NK cells. Thus, the early-onset autoimmunity and immunodeficiency are linked to functional deficits arising from altered IL-2Rβ expression and signaling in T and NK cells.
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Affiliation(s)
- Isabel Z Fernandez
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO
| | - Ryan M Baxter
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO
| | - Josselyn E Garcia-Perez
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO
| | - Elena Vendrame
- Department of Medicine, Stanford University School of Medicine, Stanford, CA
| | - Thanmayi Ranganath
- Department of Medicine, Stanford University School of Medicine, Stanford, CA
| | - Daniel S Kong
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO
| | - Karl Lundquist
- School of Physics, Georgia Institute of Technology, Atlanta, GA
| | - Tom Nguyen
- Department of Pediatrics, Division of Gastroenterology, Hepatology and Nutrition, University of Colorado School of Medicine, Digestive Health Institute, Children's Hospital Colorado, Aurora, CO
| | - Sidney Ogolla
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO
| | - Jennifer Black
- Department of Pathology and Laboratory Medicine, University of Colorado School of Medicine, Children's Hospital Colorado, Aurora, CO
| | - Csaba Galambos
- Department of Pathology and Laboratory Medicine, University of Colorado School of Medicine, Children's Hospital Colorado, Aurora, CO
| | - James C Gumbart
- School of Physics, Georgia Institute of Technology, Atlanta, GA
| | - Noor Dawany
- Department of Biomedical and Health Informatics, Children's Hospital of Philadelphia, Philadelphia, PA
| | - Judith R Kelsen
- Department of Pediatrics, Division of Gastroenterology, Children's Hospital of Philadelphia, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Edwin F de Zoeten
- Department of Pediatrics, Division of Gastroenterology, Hepatology and Nutrition, University of Colorado School of Medicine, Digestive Health Institute, Children's Hospital Colorado, Aurora, CO
| | - Ralph Quinones
- Department of Pediatrics, Division of Hematology/Oncology and Blood and Marrow Transplantation, University of Colorado School of Medicine, Children's Hospital Colorado, Aurora, CO
| | - Hesham Eissa
- Department of Pediatrics, Division of Hematology/Oncology and Blood and Marrow Transplantation, University of Colorado School of Medicine, Children's Hospital Colorado, Aurora, CO
| | - Michael R Verneris
- Department of Pediatrics, Division of Hematology/Oncology and Blood and Marrow Transplantation, University of Colorado School of Medicine, Children's Hospital Colorado, Aurora, CO
| | - Kathleen E Sullivan
- Department of Pediatrics, Division of Allergy and Immunology, Children's Hospital of Philadelphia, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | - Rosemary Rochford
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO
| | - Catherine A Blish
- Department of Medicine, Stanford University School of Medicine, Stanford, CA.,Immunology Program, School of Medicine, Stanford University, Stanford, CA
| | - Ross M Kedl
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO
| | - Cullen M Dutmer
- Department of Pediatrics, Section of Allergy and Immunology, University of Colorado School of Medicine, Children's Hospital Colorado, Aurora, CO
| | - Elena W Y Hsieh
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO .,Department of Pediatrics, Section of Allergy and Immunology, University of Colorado School of Medicine, Children's Hospital Colorado, Aurora, CO
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12
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Klein C, Waldhauer I, Nicolini VG, Freimoser-Grundschober A, Nayak T, Vugts DJ, Dunn C, Bolijn M, Benz J, Stihle M, Lang S, Roemmele M, Hofer T, van Puijenbroek E, Wittig D, Moser S, Ast O, Brünker P, Gorr IH, Neumann S, de Vera Mudry MC, Hinton H, Crameri F, Saro J, Evers S, Gerdes C, Bacac M, van Dongen G, Moessner E, Umaña P. Cergutuzumab amunaleukin (CEA-IL2v), a CEA-targeted IL-2 variant-based immunocytokine for combination cancer immunotherapy: Overcoming limitations of aldesleukin and conventional IL-2-based immunocytokines. Oncoimmunology 2017; 6:e1277306. [PMID: 28405498 PMCID: PMC5384349 DOI: 10.1080/2162402x.2016.1277306] [Citation(s) in RCA: 176] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 12/16/2016] [Accepted: 12/21/2016] [Indexed: 12/11/2022] Open
Abstract
We developed cergutuzumab amunaleukin (CEA-IL2v, RG7813), a novel monomeric CEA-targeted immunocytokine, that comprises a single IL-2 variant (IL2v) moiety with abolished CD25 binding, fused to the C-terminus of a high affinity, bivalent carcinoembryonic antigen (CEA)-specific antibody devoid of Fc-mediated effector functions. Its molecular design aims to (i) avoid preferential activation of regulatory T-cells vs. immune effector cells by removing CD25 binding; (ii) increase the therapeutic index of IL-2 therapy by (a) preferential retention at the tumor by having a lower dissociation rate from CEA-expressing cancer cells vs. IL-2R-expressing cells, (b) avoiding any FcγR-binding and Fc effector functions and (c) reduced binding to endothelial cells expressing CD25; and (iii) improve the pharmacokinetics, and thus convenience of administration, of IL-2. The crystal structure of the IL2v-IL-2Rβγ complex was determined and CEA-IL2v activity was assessed using human immune effector cells. Tumor targeting was investigated in tumor-bearing mice using 89Zr-labeled CEA-IL2v. Efficacy studies were performed in (a) syngeneic mouse models as monotherapy and combined with anti-PD-L1, and in (b) xenograft mouse models in combination with ADCC-mediating antibodies. CEA-IL2v binds to CEA with pM avidity but not to CD25, and consequently did not preferentially activate Tregs. In vivo, CEA-IL2v demonstrated superior pharmacokinetics and tumor targeting compared with a wild-type IL-2-based CEA immunocytokine (CEA-IL2wt). CEA-IL2v strongly expanded NK and CD8+ T cells, skewing the CD8+:CD4+ ratio toward CD8+ T cells both in the periphery and in the tumor, and mediated single agent efficacy in syngeneic MC38-CEA and PancO2-CEA models. Combination with trastuzumab, cetuximab and imgatuzumab, all of human IgG1 isotype, resulted in superior efficacy compared with the monotherapies alone. Combined with anti-PD-L1, CEA-IL2v mediated superior efficacy over the respective monotherapies, and over the combination with an untargeted control immunocytokine. These preclinical data support the ongoing clinical investigation of the cergutuzumab amunaleukin immunocytokine with abolished CD25 binding for the treatment of CEA-positive solid tumors in combination with PD-L1 checkpoint blockade and ADCC competent antibodies.
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Affiliation(s)
- Christian Klein
- Roche Pharma Research & Early Development, Roche Innovation Center Zurich, Schlieren, Switzerland
| | - Inja Waldhauer
- Roche Pharma Research & Early Development, Roche Innovation Center Zurich, Schlieren, Switzerland
| | - Valeria G. Nicolini
- Roche Pharma Research & Early Development, Roche Innovation Center Zurich, Schlieren, Switzerland
| | | | - Tapan Nayak
- Roche Pharma Research & Early Development, Roche Innovation Center Basel, Basel, Switzerland
| | - Danielle J. Vugts
- Roche Pharma Research & Early Development, Department of Radiology & Nuclear Medicine, VU University Medical Center, Amsterdam, the Netherlands
| | - Claire Dunn
- Roche Pharma Research & Early Development, Roche Innovation Center Zurich, Schlieren, Switzerland
| | - Marije Bolijn
- Roche Pharma Research & Early Development, Department of Radiology & Nuclear Medicine, VU University Medical Center, Amsterdam, the Netherlands
| | - Jörg Benz
- Roche Pharma Research & Early Development, Roche Innovation Center Basel, Basel, Switzerland
| | - Martine Stihle
- Roche Pharma Research & Early Development, Roche Innovation Center Basel, Basel, Switzerland
| | - Sabine Lang
- Roche Pharma Research & Early Development, Roche Innovation Center Zurich, Schlieren, Switzerland
| | - Michaele Roemmele
- Roche Pharma Research & Early Development, Roche Innovation Center Zurich, Schlieren, Switzerland
| | - Thomas Hofer
- Roche Pharma Research & Early Development, Roche Innovation Center Zurich, Schlieren, Switzerland
| | - Erwin van Puijenbroek
- Roche Pharma Research & Early Development, Roche Innovation Center Zurich, Schlieren, Switzerland
| | - David Wittig
- Roche Pharma Research & Early Development, Roche Innovation Center Zurich, Schlieren, Switzerland
| | - Samuel Moser
- Roche Pharma Research & Early Development, Roche Innovation Center Zurich, Schlieren, Switzerland
| | - Oliver Ast
- Roche Pharma Research & Early Development, Roche Innovation Center Zurich, Schlieren, Switzerland
| | - Peter Brünker
- Roche Pharma Research & Early Development, Roche Innovation Center Zurich, Schlieren, Switzerland
| | - Ingo H. Gorr
- Roche Pharma Research & Early Development, Roche Innovation Center Munich, Penzberg, Germany
| | - Sebastian Neumann
- Roche Pharma Research & Early Development, Roche Innovation Center Basel, Basel, Switzerland
| | | | - Heather Hinton
- Roche Pharma Research & Early Development, Roche Innovation Center Zurich, Schlieren, Switzerland
| | - Flavio Crameri
- Roche Pharma Research & Early Development, Roche Innovation Center Basel, Basel, Switzerland
| | - Jose Saro
- Roche Pharma Research & Early Development, Roche Innovation Center Zurich, Schlieren, Switzerland
| | - Stefan Evers
- Roche Pharma Research & Early Development, Roche Innovation Center Zurich, Schlieren, Switzerland
| | - Christian Gerdes
- Roche Pharma Research & Early Development, Roche Innovation Center Zurich, Schlieren, Switzerland
| | - Marina Bacac
- Roche Pharma Research & Early Development, Roche Innovation Center Zurich, Schlieren, Switzerland
| | - Guus van Dongen
- Roche Pharma Research & Early Development, Department of Radiology & Nuclear Medicine, VU University Medical Center, Amsterdam, the Netherlands
| | - Ekkehard Moessner
- Roche Pharma Research & Early Development, Roche Innovation Center Zurich, Schlieren, Switzerland
| | - Pablo Umaña
- Roche Pharma Research & Early Development, Roche Innovation Center Zurich, Schlieren, Switzerland
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13
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Lee HK, Keum S, Sheng H, Warner DS, Lo DC, Marchuk DA. Natural allelic variation of the IL-21 receptor modulates ischemic stroke infarct volume. J Clin Invest 2016; 126:2827-38. [PMID: 27400126 DOI: 10.1172/jci84491] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Accepted: 05/12/2016] [Indexed: 02/06/2023] Open
Abstract
Risk for ischemic stroke has a strong genetic basis, but heritable factors also contribute to the extent of damage after a stroke has occurred. We previously identified a locus on distal mouse chromosome 7 that contributes over 50% of the variation in postischemic cerebral infarct volume observed between inbred strains. Here, we used ancestral haplotype analysis to fine-map this locus to 12 candidate genes. The gene encoding the IL-21 receptor (Il21r) showed a marked difference in strain-specific transcription levels and coding variants in neonatal and adult cortical tissue. Collateral vessel connections were moderately reduced in Il21r-deficient mice, and cerebral infarct volume increased 2.3-fold, suggesting that Il21r modulates both collateral vessel anatomy and innate neuroprotection. In brain slice explants, oxygen deprivation (OD) activated apoptotic pathways and increased neuronal cell death in IL-21 receptor-deficient (IL-21R-deficient) mice compared with control animals. We determined that the neuroprotective effects of IL-21R arose from signaling through JAK/STAT pathways and upregulation of caspase 3. Thus, natural genetic variation in murine Il21r influences neuronal cell viability after ischemia by modulating receptor function and downstream signal transduction. The identification of neuroprotective genes based on naturally occurring allelic variations has the potential to inform the development of drug targets for ischemic stroke treatment.
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14
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Craven TW, Cho MK, Traaseth NJ, Bonneau R, Kirshenbaum K. A Miniature Protein Stabilized by a Cation-π Interaction Network. J Am Chem Soc 2016; 138:1543-50. [PMID: 26812069 PMCID: PMC4867217 DOI: 10.1021/jacs.5b10285] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The design of folded miniature proteins is predicated on establishing noncovalent interactions that direct the self-assembly of discrete thermostable tertiary structures. In this work, we describe how a network of cation-π interactions present in proteins containing "WSXWS motifs" can be emulated to stabilize the core of a miniature protein. This 19-residue protein sequence recapitulates a set of interdigitated arginine and tryptophan residues that stabilize a distinctive β-strand:loop:PPII-helix topology. Validation of the compact fold determined by NMR was carried out by mutagenesis of the cation-π network and by comparison to the corresponding disulfide-bridged structure. These results support the involvement of a coordinated set of cation-π interactions that stabilize the tertiary structure.
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Affiliation(s)
- Timothy W. Craven
- Department of Chemistry, New York University, 100 Washington Square East, New York, NY
- Department of Biology, Center for Genomics and Systems Biology, New York University, 12 Waverly Pl., New York, NY
| | - Min-Kyu Cho
- Department of Chemistry, New York University, 100 Washington Square East, New York, NY
| | - Nathaniel J. Traaseth
- Department of Chemistry, New York University, 100 Washington Square East, New York, NY
| | - Richard Bonneau
- Department of Biology, Center for Genomics and Systems Biology, New York University, 12 Waverly Pl., New York, NY
- Department of Computer Science, Courant Institute of Mathematical Sciences, New York University, New York, NY
- Simons Center for Data Analysis, New York, NY
| | - Kent Kirshenbaum
- Department of Chemistry, New York University, 100 Washington Square East, New York, NY
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15
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16
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Siupka P, Hamming OT, Kang L, Gad HH, Hartmann R. A conserved sugar bridge connected to the WSXWS motif has an important role for transport of IL-21R to the plasma membrane. Genes Immun 2015; 16:405-13. [PMID: 26043171 DOI: 10.1038/gene.2015.22] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 04/23/2015] [Accepted: 04/24/2015] [Indexed: 11/09/2022]
Abstract
Interleukin-21 (IL-21) is a class I cytokine that belongs to the γc-subfamily of cytokines and regulates immune responses. It signals through a heterodimeric receptor complex composed of the IL-21R1 and γc-receptor chains. A characteristic feature of class I cytokine receptors is the presence of a consensus motif WSXWS (WS motif) in the membrane proximal fibronectin type III domain (FNIII) of these receptors. We recently described the structure of the IL-21R:IL-21 complex and showed that the first tryptophan of the WS motif of IL-21R is mannosylated and involved in formation of a sugar bridge that connects the two FNIII domains of the receptor. Furthermore, a mutation within the WS motif of IL-21R was recently shown to cause a novel kind of primary immunodeficiency syndrome (PID). Here, we report the structure of IL-21R alone, which shows that the sugar bridge forms independently of whether IL-21R binds IL-21 or not, and we furthermore investigate the role of this bridge in the export of IL-21R and γC to the plasma membrane. Thus, we provide a molecular explanation for how mutations in the WS motif may cause PIDs.
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Affiliation(s)
- P Siupka
- Department of Molecular Biology and Genetics, University of Aarhus, Aarhus, Denmark
| | - O T Hamming
- Department of Molecular Biology and Genetics, University of Aarhus, Aarhus, Denmark
| | - L Kang
- Novo Nordisk R&D Center China, Beijing, China
| | - H H Gad
- Department of Molecular Biology and Genetics, University of Aarhus, Aarhus, Denmark
| | - R Hartmann
- Department of Molecular Biology and Genetics, University of Aarhus, Aarhus, Denmark
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17
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Szabó R, Láng O, Láng J, Illyés E, Kőhidai L, Hudecz F. Effect of SXWS/WSXWS peptides on chemotaxis and adhesion of the macrophage-like cell line J774. J Mol Recognit 2015; 28:253-60. [PMID: 25683456 DOI: 10.1002/jmr.2439] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2014] [Revised: 09/28/2014] [Accepted: 09/28/2014] [Indexed: 11/06/2022]
Abstract
WSXWS motif is a conserved amino acid sequence that is present in type I cytokine receptors. This motif that can be found both in the ligand binding chains and signal transducer molecule of the receptors with different amino acids at the position "X" plays a role in the receptor folding, ligand binding and signal transduction as well. Structural analysis proved that WSEWS motif of IL-6R is located in a highly accessible location in the protein. Structural properties and chemotaxis of a tetrapeptide library with SXWS sequence, where X was the 19 proteinogenic amino acids except cystein were systematically studied earlier. It has been proved that C-terminal amidation and the identity of amino acid X had a pronounced influence on the chemotactic properties but less of the structure of the peptides. Here, we present our findings on the effect of a tetrapeptide and a pentapeptide library with the sequence of SXWS and WSXWS on the chemotaxis and adhesion of J774 murine macrophage cell line. We studied the effect of the presence/absence of N-terminal tryptophan and the different amino acids at the X position on these physiological responses. Results indicated that amino acid X had a marked influence on chemotaxis, adhesion as well as on proliferation induced by (W)SXWS peptides. Elongation of SXWS sequence with a tryptophan at the N terminus also altered pronouncedly all the physiological responses of the cells studied. A good correlation could be observed between the chemotaxis and the proliferation and physicochemical parameters of the amino acid X.
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Affiliation(s)
- Rita Szabó
- Research Group of Peptide Chemistry, Hungarian Academy of Sciences, P.O. Box 32, H-1518, Budapest, 112, Hungary
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18
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Olsen JG, Kragelund BB. Who climbs the tryptophan ladder? On the structure and function of the WSXWS motif in cytokine receptors and thrombospondin repeats. Cytokine Growth Factor Rev 2014; 25:337-41. [PMID: 24861947 DOI: 10.1016/j.cytogfr.2014.04.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Accepted: 04/29/2014] [Indexed: 12/31/2022]
Abstract
For decades, a spectacular structural motif has been the focus of research in two families of animal membrane proteins: the hematopoietic cytokine type I receptors (HCR) and the thrombospondin repeat type 1 (TSR-1) domain containing proteins. Although these families include some of the best-studied and pharmaceutically most interesting human proteins, the function of the motif remains elusive. Here we show that the molecular details of the motifs are the same; that it has arisen through convergent evolution, and we argue that the same ligand binding function is maintained and suggest that the ligand can be found in the extracellular matrix (ECM). We term the motif the tryptophan ladder and suggest a function based on a comparative analysis.
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Affiliation(s)
- Johan G Olsen
- Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, Ole Maaloes Vej 5, DK-2200 Copenhagen, Denmark
| | - Birthe B Kragelund
- Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, Ole Maaloes Vej 5, DK-2200 Copenhagen, Denmark.
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19
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Abstract
Severe congenital neutropenia (SCN) is characterized by low numbers of peripheral neutrophil granulocytes and a predisposition to life-threatening bacterial infections. We describe a novel genetic SCN type in 2 unrelated families associated with recessively inherited loss-of-function mutations in CSF3R, encoding the granulocyte colony-stimulating factor (G-CSF) receptor. Family A, with 3 affected children, carried a homozygous missense mutation (NM_000760.3:c.922C>T, NP_000751.1:p.Arg308Cys), which resulted in perturbed N-glycosylation and aberrant localization to the cell surface. Family B, with 1 affected infant, carried compound heterozygous deletions provoking frameshifts and premature stop codons (NM_000760.3:c.948_963del, NP_000751.1:p.Gly316fsTer322 and NM_000760.3:c.1245del, NP_000751.1:p.Gly415fsTer432). Despite peripheral SCN, all patients had morphologic evidence of full myeloid cell maturation in bone marrow. None of the patients responded to treatment with recombinant human G-CSF. Our study highlights the genetic and morphologic SCN variability and provides evidence both for functional importance and redundancy of G-CSF receptor-mediated signaling in human granulopoiesis.
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20
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Kang JH, Hassan SA, Zhao P, Tsai-Morris CH, Dufau ML. Impact of subdomain D1 of the short form S1b of the human prolactin receptor on its inhibitory action on the function of the long form of the receptor induced by prolactin. Biochim Biophys Acta Gen Subj 2014; 1840:2272-80. [PMID: 24735798 DOI: 10.1016/j.bbagen.2014.04.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Revised: 03/11/2014] [Accepted: 04/08/2014] [Indexed: 12/12/2022]
Abstract
BACKGROUND Long-form (LF) homodimers of the human prolactin receptor (PRLR) mediate prolactin's diverse actions. Short form S1b inhibits the LF function through heterodimerization. Reduced S1b/LF-ratio in breast cancer could contribute to tumor development/progression. Current work defines the structural and functional relevance of the D1 domain of S1b on its inhibitory function on prolactin-induced LF function. METHODS Studies were conducted using mutagenesis, promoter/signaling analyses, bioluminescence resonance energy transfer (BRET) and molecular modeling approaches. RESULTS Mutation of E69 in D1 S1b or adjacent residues at the receptor surface near to the binding pocket (S) causes loss of its inhibitory effect while mutations away from this region (A) or in the D2 domain display inhibitory action as the wild-type. All S1b mutants preserved prolactin-induced Jak2 activation. BRET reveals an increased affinity in D1 mutated S1b (S) homodimers in transfected cells stably expressing LF. In contrast, affinity in S1b homodimers with either D1 (A) or D2 mutations remained unchanged. This favors LF mediated signaling induced by prolactin. Molecular dynamics simulations show that mutations (S) elicit major conformational changes that propagate downward to the D1/D2 interface and change their relative orientation in the dimers. CONCLUSIONS These findings demonstrate the essential role of D1 on the S1b structure and its inhibitory action on prolactin-induced LF-mediated function. GENERAL SIGNIFICANCE Major changes in receptor conformation and dimerization affinity are triggered by single mutations in critical regions of D1. Our structure-function/simulation studies provide a basis for modeling and design of small molecules to enhance inhibition of LF activation for potential use in breast cancer treatment.
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Affiliation(s)
- J-H Kang
- Section on Molecular Endocrinology, Program on Developmental Endocrinology and Genetics, Eunice Kennedy Shriver National Institutes of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-4510, USA
| | - S A Hassan
- Center for Molecular Modeling, Division of Computational Bioscience, Center for Information Technology, National Institutes of Health, Bethesda, MD 20892-4510, USA
| | - P Zhao
- Section on Molecular Endocrinology, Program on Developmental Endocrinology and Genetics, Eunice Kennedy Shriver National Institutes of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-4510, USA
| | - C H Tsai-Morris
- Section on Molecular Endocrinology, Program on Developmental Endocrinology and Genetics, Eunice Kennedy Shriver National Institutes of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-4510, USA
| | - M L Dufau
- Section on Molecular Endocrinology, Program on Developmental Endocrinology and Genetics, Eunice Kennedy Shriver National Institutes of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-4510, USA.
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21
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Gras D, Chanez P, Vachier I, Petit A, Bourdin A. Bronchial epithelium as a target for innovative treatments in asthma. Pharmacol Ther 2013; 140:290-305. [PMID: 23880290 DOI: 10.1016/j.pharmthera.2013.07.008] [Citation(s) in RCA: 95] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Accepted: 07/10/2013] [Indexed: 01/03/2023]
Abstract
Increasing evidence of a critical role played by the bronchial epithelium in airway homeostasis is opening new therapeutic avenues. Its unique situation at the interface with the environment suggests that the subtle regulation orchestrated by the epithelium between tolerance and specific immune response might be impaired in asthma. Airway mucus is acting as a physical and a biological fluid between the environment and the epithelium, synergistically moved by the cilia. In asthma, excessive mucus production is a hallmark of airway remodeling. Since many years we tried to therapeutically target mucus hypersecretion, but actually this option is still not achieved. The present review discusses the dynamic processes regulating airway mucus production. Airway inflammation is central in current asthma management. Understanding of how the airway epithelium influences the TH2 paradigm in response to deleterious agents is improving. The multiple receptors expressed by the airway epithelium are the transducers of the biological signals induced by various invasive agents to develop the most adapted response. Airway remodeling is observed in severe chronic airway diseases and may result from ongoing disturbance of signal transduction and epithelial renewal. Chronic airway diseases such as asthma will require assessment of these epithelial abnormalities to identify phenotypic characteristics associated with predicting a clinical benefit for epithelial-directed therapies.
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Affiliation(s)
- Delphine Gras
- UMR INSERM U1067 CNRS 7333, Aix-Marseille University, Marseille, France
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22
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C. elegans DPY-19 is a C-mannosyltransferase glycosylating thrombospondin repeats. Mol Cell 2013; 50:295-302. [PMID: 23562325 DOI: 10.1016/j.molcel.2013.03.003] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Revised: 01/22/2013] [Accepted: 03/01/2013] [Indexed: 11/20/2022]
Abstract
Among the different types of protein glycosylation, C-mannosylation of tryptophan residues stands out because of the unique linkage formed between sugar and protein. Instead of the typical O- or N-glycosidic linkage, a C-C bond is used for attachment of a single mannose. C-mannose is characteristically found in thrombospondin type 1 repeats and in the WSXWS motif of type I cytokine receptors. The genetic base of the enzymatic activity catalyzing C-mannosylation was not known. Here we demonstrate that Caenorhabditis elegans DPY-19 is a C-mannosyltransferase. DPY-19 exhibits topological and sequential homology to the N-glycan oligosaccharyltransferase, highlighting an evolutionary link between N- and C-glycosylation. We show that the C. elegans surface receptors MIG-21 and UNC-5 are acceptor substrates of DPY-19 and that C-mannosylation is essential for the secretion of soluble MIG-21. Thereby, our data provide an explanation for the previously described identical Q neuroblast migration phenotypes of dpy-19 and mig-21 mutants.
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Kotlarz D, Ziętara N, Uzel G, Weidemann T, Braun CJ, Diestelhorst J, Krawitz PM, Robinson PN, Hecht J, Puchałka J, Gertz EM, Schäffer AA, Lawrence MG, Kardava L, Pfeifer D, Baumann U, Pfister ED, Hanson EP, Schambach A, Jacobs R, Kreipe H, Moir S, Milner JD, Schwille P, Mundlos S, Klein C. Loss-of-function mutations in the IL-21 receptor gene cause a primary immunodeficiency syndrome. ACTA ACUST UNITED AC 2013; 210:433-43. [PMID: 23440042 PMCID: PMC3600901 DOI: 10.1084/jem.20111229] [Citation(s) in RCA: 155] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
A primary immunodeficiency syndrome caused by loss-of-function mutations in the IL-21 receptor exhibits impaired B, T, and NK cell function. Primary immunodeficiencies (PIDs) represent exquisite models for studying mechanisms of human host defense. In this study, we report on two unrelated kindreds, with two patients each, who had cryptosporidial infections associated with chronic cholangitis and liver disease. Using exome and candidate gene sequencing, we identified two distinct homozygous loss-of-function mutations in the interleukin-21 receptor gene (IL21R; c.G602T, p.Arg201Leu and c.240_245delCTGCCA, p.C81_H82del). The IL-21RArg201Leu mutation causes aberrant trafficking of the IL-21R to the plasma membrane, abrogates IL-21 ligand binding, and leads to defective phosphorylation of signal transducer and activator of transcription 1 (STAT1), STAT3, and STAT5. We observed impaired IL-21–induced proliferation and immunoglobulin class-switching in B cells, cytokine production in T cells, and NK cell cytotoxicity. Our study indicates that human IL-21R deficiency causes an immunodeficiency and highlights the need for early diagnosis and allogeneic hematopoietic stem cell transplantation in affected children.
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Affiliation(s)
- Daniel Kotlarz
- Department of Pediatric Hematology/Oncology, Hannover Medical School, 30625 Hannover, Germany
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24
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The WSXWS motif in cytokine receptors is a molecular switch involved in receptor activation: insight from structures of the prolactin receptor. Structure 2012; 20:270-82. [PMID: 22325776 DOI: 10.1016/j.str.2011.12.010] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2011] [Revised: 11/17/2011] [Accepted: 12/12/2011] [Indexed: 11/20/2022]
Abstract
The prolactin receptor (PRLR) is activated by binding of prolactin in a 2:1 complex, but the activation mechanism is poorly understood. PRLR has a conserved WSXWS motif generic to cytokine class I receptors. We have determined the nuclear magnetic resonance solution structure of the membrane proximal domain of the human PRLR and find that the tryptophans of the motif adopt a T-stack conformation in the unbound state. By contrast, in the hormone bound state, a Trp/Arg-ladder is formed. The conformational change is hormone-dependent and influences the receptor-receptor dimerization site 3. In the constitutively active, breast cancer-related receptor mutant PRLR(I146L), we observed a stabilization of the dimeric state and a change in the dynamics of the motif. Here we demonstrate a structural link between the WSXWS motif, hormone binding, and receptor dimerization and propose it as a general mechanism for class 1 receptor activation.
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25
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Jones LL, Chaturvedi V, Uyttenhove C, Van Snick J, Vignali DAA. Distinct subunit pairing criteria within the heterodimeric IL-12 cytokine family. Mol Immunol 2012; 51:234-44. [PMID: 22487722 DOI: 10.1016/j.molimm.2012.03.025] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Accepted: 03/17/2012] [Indexed: 01/07/2023]
Abstract
The heterodimeric IL-12 cytokine family is characterized by the sharing of three α (p19, p28, p35) and two β (p40 and Ebi3) subunits, and includes IL-12 (p35/p40), IL-23 (p19/p40), IL-27 (p28/Ebi3) and IL-35 (p35/Ebi3). In this study, the dimerization interfaces of IL-12 family members were characterized, with emphasis on IL-35. Ebi3 and p35 subunits from human and mouse paired effectively with each other, indicating there is no species barrier to IL-35 dimerization and suggesting a conserved dimerization interface. Specific p35 residues that contribute to formation of the IL-12 interface were assessed for their contribution to the IL-35 interface, and candidate Ebi3 residues were screened for their contribution to both IL-27 and IL-35 interfaces. Several residues were identified as critical to the IL-12 or IL-27 interfaces. Conversely, no single mutation was identified that completely disrupts p35/Ebi3 pairing. Linear alanine scanning mutagenesis on both p35 and Ebi3 subunits was performed, focusing on residues that are conserved between the mouse and human proteins. Additionally, a structure-based alanine-scanning approach in which mutations were clustered based on proximitiy was performed on the p35 subunit. Both approaches suggest that IL-35 has distinct criteria for subunit pairing and is remarkabley less sensitive to structural perturbation than IL-12 and IL-27. Additionally, studies using a panel of anti-p35 and anti-Ebi3 antibodies indicate differential availability of epitopes within IL-12 family members that share these subunits, suggesting that IL-35 has distinct structural features, relative to IL-12 and IL-27. These results may be useful in future directed therapeutic targeting of IL-12 family members.
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Affiliation(s)
- Lindsay L Jones
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
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26
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Watowich SS. The erythropoietin receptor: molecular structure and hematopoietic signaling pathways. J Investig Med 2012; 59:1067-72. [PMID: 21307776 DOI: 10.2310/jim.0b013e31820fb28c] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The process of erythropoiesis in the fetal liver and adult bone marrow is regulated by the hormone erythropoietin (Epo), which is produced in the kidney at low levels under homeostatic conditions. Defects in Epo production result in severe anemia; use of recombinant hormone has improved the lives of patients with renal failure or anemia because of bone marrow suppression. Deletion of the Epo gene in mice leads to embryonic lethality at days 13 to 15, coincident with the establishment of definitive (adult-type) erythropoiesis and underscoring the absolute necessity of Epo function in vivo. Epo has proven to be a successful pharmaceutical agent, one of the early triumphs of recombinant protein technology. Because of its clinical importance, a great deal of attention has focused on the molecular mechanisms of Epo-regulated erythropoiesis. This review highlights the basic concepts of Epo signal transduction within the hematopoietic system, the major site of Epo action in vivo.
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Affiliation(s)
- Stephanie S Watowich
- Department of Immunology and Center for Inflammation and Cancer, The University of Texas M. D. Anderson Cancer Center, Houston, Texas, USA.
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27
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Jones LL, Vignali DAA. Molecular interactions within the IL-6/IL-12 cytokine/receptor superfamily. Immunol Res 2012; 51:5-14. [PMID: 21553332 DOI: 10.1007/s12026-011-8209-y] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Production of cytokines by immune cells in response to stimuli and the binding of cytokines to specific receptors on target cells is a central feature of the immune response. The IL-12 cytokine family is particularly influential in determining the fate of T cells and is characterized by the sharing of cytokine and receptor subunits. A thorough understanding of the molecular interactions within this family will be a key to the development of therapeutic inhibitors or enhancers of IL-12 family function. While the current structural and molecular data for IL-12 family members is limited, there is ample information on the structurally related IL-6 cytokine family. This review will summarize the current structural and mutagenesis data within the IL-12 family and will attempt to utilize similarities between the IL-6 and IL-12 families to understand molecular interactions between IL-12 family subunits and with receptor components.
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Affiliation(s)
- Lindsay L Jones
- Department of Immunology, St. Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA
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Hamming OJ, Kang L, Svensson A, Karlsen JL, Rahbek-Nielsen H, Paludan SR, Hjorth SA, Bondensgaard K, Hartmann R. Crystal structure of interleukin-21 receptor (IL-21R) bound to IL-21 reveals that sugar chain interacting with WSXWS motif is integral part of IL-21R. J Biol Chem 2012; 287:9454-60. [PMID: 22235133 DOI: 10.1074/jbc.m111.311084] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
IL-21 is a class I cytokine that exerts pleiotropic effects on both innate and adaptive immune responses. It signals through a heterodimeric receptor complex consisting of the IL-21 receptor (IL-21R) and the common γ-chain. A hallmark of the class I cytokine receptors is the class I cytokine receptor signature motif (WSXWS). The exact role of this motif has not been determined yet; however, it has been implicated in diverse functions, including ligand binding, receptor internalization, proper folding, and export, as well as signal transduction. Furthermore, the WXXW motif is known to be a consensus sequence for C-mannosylation. Here, we present the crystal structure of IL-21 bound to IL-21R and reveal that the WSXWS motif of IL-21R is C-mannosylated at the first tryptophan. We furthermore demonstrate that a sugar chain bridges the two fibronectin domains that constitute the extracellular domain of IL-21R and anchors at the WSXWS motif through an extensive hydrogen bonding network, including mannosylation. The glycan thus transforms the V-shaped receptor into an A-frame. This finding offers a novel structural explanation of the role of the class I cytokine signature motif.
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Affiliation(s)
- Ole J Hamming
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus C, Denmark
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29
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Wang T, Huang W, Costa MM, Martin SAM, Secombes CJ. Two copies of the genes encoding the subunits of putative interleukin (IL)-4/IL-13 receptors, IL-4Rα, IL-13Rα1 and IL-13Rα2, have been identified in rainbow trout (Oncorhynchus mykiss) and have complex patterns of expression and modulation. Immunogenetics 2011; 63:235-53. [PMID: 21210100 DOI: 10.1007/s00251-010-0508-2] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2010] [Accepted: 12/20/2010] [Indexed: 01/04/2023]
Abstract
Mammalian interleukin-4 (IL-4) and IL-13 are T helper type 2 (Th2) cytokines with pleiotropic functions in immunity. They signal through receptors containing IL-4Rα and IL-2Rγ or IL-13Rα1. In addition, a decoy receptor, IL-13Rα2, is known to exist and modulates the function of IL-13. The existence of fish orthologues to mammalian IL-4 and IL-13 is still under debate. However, the receptor chains have been predicted in zebrafish, and we have previously cloned IL-2Rγ and IL-13Rα2 in rainbow trout. In this study, we have cloned a further five novel trout IL-4/13 receptors. Thus, each of the IL-4Rα, IL-13Rα1 and IL-13Rα2 chains has two copies. The identities of the receptors is supported by homology analysis, characteristic domain structure, phylogenetic tree analysis and synteny analysis in zebrafish. However, the characteristic WSXWS motif of structural importance in mammalian type I cytokine receptors is missing in all fish IL-4Rα and IL-13Rα1 molecules. All the receptors have a characteristic domain structure that is similar to their mammalian counterparts except for IL-13Rα1b that has the N-terminal Ig domain missing. Since this Ig domain is a specific and critical binding unit for IL-13 but not for IL-4 signalling, its absence potentially converts the IL-13Rα1b into a receptor that can only signal via IL-4 ligation. The existence of duplicated receptor genes perhaps suggests that more ligands still remain to be discovered that will bind these receptors. The duplicated receptors are differentially expressed in most tissues and cell lines examined, and their expression can be modulated by LPS, polyIC and IFN-γ in cell lines. In contrast, the T-cell stimulant phytohaemagglutinin increased the expression of IL-4Rα1 and IL-4Rα2, but not IL-13Rα1/2, suggesting a role of an IL-4-like molecule in T-cell growth/activation in fish.
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Affiliation(s)
- Tiehui Wang
- Scottish Fish Immunology Research Centre, School of Biological Sciences, University of Aberdeen, Aberdeen, AB24 2TZ, UK
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30
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Ihara Y, Inai Y, Ikezaki M. Protein C-Mannosylation and Its Prospective Functions in the Cell. TRENDS GLYCOSCI GLYC 2011. [DOI: 10.4052/tigg.23.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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31
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Ihara Y, Manabe S, Ikezaki M, Inai Y, Matsui ISL, Ohta Y, Muroi E, Ito Y. C-Mannosylated peptides derived from the thrombospondin type 1 repeat interact with Hsc70 to modulate its signaling in RAW264.7 cells. Glycobiology 2010; 20:1298-310. [PMID: 20581007 DOI: 10.1093/glycob/cwq096] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The thrombospondin type 1 repeat (TSR) is a functional module of proteins called TSR superfamily proteins (e.g., thrombospondin, F-spondin, mindin, etc.) and includes a conserved Trp-x-x-Trp (W-x-x-W) motif, in which the first Trp residue is preferably modified by C-mannosylation. We previously reported that synthesized C-mannosylated TSR-derived peptides (e.g., C-Man-WSPW) specifically enhanced lipopolysaccharide-induced signaling in macrophage-like RAW264.7 cells. In this study, we searched for the proteins that bind to C-mannosylated TSR-derived peptides in RAW264.7 cells and identified heat shock cognate protein 70 (Hsc70). The binding affinity of Hsc70 for C-mannosylated peptides in solution was higher than that for the peptides without C-mannose. The binding was influenced by a nucleotide-induced conformational change of Hsc70, and C-mannosylated peptides preferred the substrate-binding domain of Hsc70. Furthermore, in RAW264.7 cells, addition of Hsc70 stimulated cellular signaling to produce tumor necrosis factor-alpha, via transforming growth factor-beta-activated kinase 1, and the Hsc70-induced signaling was enhanced more in the presence of the peptides with C-mannose than that without C-mannose, suggesting functional interaction between Hsc70 and the C-mannosylated peptides in the cells. Together, these results demonstrate a novel function of the C-mannosylation of TSR-derived peptides in terms of interaction with Hsc70 to regulate cellular signaling.
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Affiliation(s)
- Yoshito Ihara
- Department of Biochemistry, Wakayama Medical University, Wakayama, Japan.
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32
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Insertion of an NPVY sequence into the cytosolic domain of the erythropoietin receptor selectively affects erythropoietin-mediated signalling and function. Biochem J 2010; 427:305-12. [DOI: 10.1042/bj20091951] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
EPO (erythropoietin), the major hormone regulating erythropoiesis, functions via activation of its cell-surface receptor (EPO-R) present on erythroid progenitor cells. One of the most striking properties of EPO-R is its low expression on the cell surface, as opposed to its high intracellular levels. The low cell-surface expression of EPO-R may thus limit the efficacy of EPO that is routinely used to treat primary and secondary anaemia. In a recent study [Nahari, Barzilay, Hirschberg and Neumann (2008) Biochem. J. 410, 409–416] we have shown that insertion of an NPVY sequence into the intracellular domain of EPO-R increases its cell-surface expression. In the present study we demonstrate that this NPVY EPO-R insert has a selective effect on EPO-mediated downstream signalling in Ba/F3 cells expressing this receptor (NPVY-EPO-R). This is monitored by increased phosphorylation of the NPVY-EPO-R (on Tyr479), Akt, JAK2 (Janus kinase 2) and ERK1/2 (extracellular-signal-regulated kinase 1/2), but not STAT5 (signal transducer and activator of transcription 5), as compared with cells expressing wild-type EPO-R. This enhanced signalling is reflected in augmented proliferation at low EPO levels (0.05 units/ml) and protection against etoposide-induced apoptosis. Increased cell-surface levels of NPVY-EPO-R are most probably not sufficient to mediate these effects as the A234E-EPO-R mutant that is expressed at high cell-surface levels does not confer an augmented response to EPO. Taken together, we demonstrate that insertion of an NPVY sequence into the cytosolic domain of the EPO-R confers not only improved maturation, but also selectively affects EPO-mediated signalling resulting in an improved responsiveness to EPO reflected in cell proliferation and protection against apoptosis.
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33
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Abstract
Hilton's passion for blood makes his pulse race.
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35
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Hur YJ, Kim JG, Whang KY, Kim YB. Molecular cloning and expression analysis of CD127 in pig. Anim Biotechnol 2009; 20:40-5. [PMID: 19160087 DOI: 10.1080/10495390802594552] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
CD127 (the alpha chain of the IL-7 receptor) is an 80 kDa type I membrane glycoprotein that mediates the signal for the differentiation, maturation, and survival of lymphocyte development. In this study, the full-length cDNA of pig Cd127 was cloned and sequenced. Pig CD127 cDNA contains an open reading frame (1,380 bp) encoding 459 amino acids. Phylogenetic analysis revealed that pig CD127 is most homologous to that of cow (Bos taurus) with 87% amino acid identity and less homologous to that of chicken (Gallus gallus) with 36% amino acid identity among those of species. Structurally, pig CD127 has well-conserved cytoplasmic tail that transmits a signal and little diversity of extracellular domain, compared with those of other mammalian species. Expression analysis indicates that the mRNA transcript of pig CD127 is mainly detected in lymphoid tissues, but still detected in nonlymphoid tissues. Future studies will be focused on determining a more defined expression pattern of pig CD127 and the role of CD127 during the lymphocyte development in pigs.
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Affiliation(s)
- Yu Jin Hur
- Division of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul, Republic of Korea
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36
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McElroy CA, Dohm JA, Walsh STR. Structural and biophysical studies of the human IL-7/IL-7Ralpha complex. Structure 2009; 17:54-65. [PMID: 19141282 DOI: 10.1016/j.str.2008.10.019] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2008] [Revised: 10/16/2008] [Accepted: 10/22/2008] [Indexed: 01/25/2023]
Abstract
IL-7 and IL-7Ralpha bind the gamma(c) receptor, forming a complex crucial to several signaling cascades leading to the development and homeostasis of T and B cells. We report that the IL-7Ralpha ectodomain uses glycosylation to modulate its binding constants to IL-7, unlike the other receptors in the gamma(c) family. IL-7 binds glycosylated IL-7Ralpha 300-fold more tightly than unglycosylated IL-7Ralpha, and the enhanced affinity is attributed primarily to an accelerated on rate. Structural comparison of IL-7 in complex to both forms of IL-7Ralpha reveals that glycosylation does not participate directly in the binding interface. The SCID mutations of IL-7Ralpha locate outside the binding interface with IL-7, suggesting that the expressed mutations cause protein folding defects in IL-7Ralpha. The IL-7/IL-7Ralpha structures provide a window into the molecular recognition events of the IL-7 signaling cascade and provide sites to target for designing new therapeutics to treat IL-7-related diseases.
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Affiliation(s)
- Craig A McElroy
- Department of Molecular and Cellular Biochemistry, College of Medicine, Comprehensive Cancer Center, Ohio State University, 467 Hamilton Hall, 1645 Neil Avenue, Columbus, OH 43210, USA
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37
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Zebrafish granulocyte colony-stimulating factor receptor signaling promotes myelopoiesis and myeloid cell migration. Blood 2009; 113:2535-46. [PMID: 19139076 DOI: 10.1182/blood-2008-07-171967] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Granulocyte colony-stimulating factor receptor (GCSFR) signaling participates in the production of neutrophilic granulocytes during normal hematopoietic development, with a particularly important role during emergency hematopoiesis. This study describes the characterization of the zebrafish gcsf and gcsfr genes, which showed broad conservation and similar regulation to their mammalian counterparts. Morpholino-mediated knockdown of gcsfr and overexpression of gcsf revealed the presence of an anterior population of myeloid cells during primitive hematopoiesis that was dependent on GCSF/GCSFR for development and migration. This contrasted with a posterior domain that was largely independent of this pathway. Definitive myelopoiesis was also partially dependent on a functional GCSF/GCSFR pathway. Injection of bacterial lipopolysaccharide elicited significant induction of gcsf expression and emergency production of myeloid cells, which was abrogated by gcsfr knockdown. Collectively, these data demonstrate GCSF/GCSFR to be a conserved signaling system for facilitating the production of multiple myeloid cell lineages in both homeostatic and emergency conditions, as well as for early myeloid cell migration, establishing a useful experimental platform for further dissection of this pathway.
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Kimber W, Peelman F, Prieur X, Wangensteen T, O'Rahilly S, Tavernier J, Farooqi IS. Functional characterization of naturally occurring pathogenic mutations in the human leptin receptor. Endocrinology 2008; 149:6043-52. [PMID: 18703626 DOI: 10.1210/en.2008-0544] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We have recently reported the first naturally occurring missense mutations in the leptin receptor (LR) in patients with severe obesity. We have examined the molecular mechanisms by which these extracellular domain mutations disrupt LR signaling. The Ala409Glu mutant receptor is expressed at the cell surface, binds leptin normally but fails to signal to downstream pathways. A409 is present on the surface-exposed region of the Ig-like domain that forms the binding site III for interaction with leptin. This binding site does not appear to contribute to the binding affinity of leptin to its receptor but is critical for receptor activation in response to ligand binding. The Trp664Arg and His684Pro mutations are predicted to impair receptor folding. Both mutants result in a complete inability to signal to downstream pathways despite evidence for some residual cell surface expression and ligand binding. The Arg612His mutant falls in the second subdomain of the high-affinity binding site for leptin, and results in a receptor that shows evidence for intracellular retention but retains some residual signaling. These studies, which represent the first detailed characterization of the functional properties of naturally occurring missense mutations in the human LR, indicate that most such mutations affect receptor folding and expression at the cell surface rather than primarily impairing ligand binding. The exception is Ala409Glu, which interferes with the coupling of ligand binding to receptor activation. Naturally occurring mutations associated with human obesity are valuable tools with which to explore structure/function relationships within the LR.
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Affiliation(s)
- Wendy Kimber
- University of Cambridge Metabolic Research Laboratories, Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge CB2 0QQ, United Kingdom
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39
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Luther KB, Haltiwanger RS. Role of unusual O-glycans in intercellular signaling. Int J Biochem Cell Biol 2008; 41:1011-24. [PMID: 18952191 DOI: 10.1016/j.biocel.2008.10.001] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2008] [Revised: 09/22/2008] [Accepted: 10/03/2008] [Indexed: 01/09/2023]
Abstract
In the last two decades, our knowledge of the role of glycans in development and signal transduction has expanded enormously. While most work has focused on the importance of N-linked or mucin-type O-linked glycosylation, recent work has highlighted the importance of several more unusual forms of glycosylation that are the focus of this review. In particular, the ability of O-fucose glycans on the epidermal growth factor-like (EGF) repeats of Notch to modulate signaling places glycosylation alongside phosphorylation as a means to modulate protein-protein interactions and their resultant downstream signals. The recent discovery that O-glucose modification of Notch EGF repeats is also required for Notch function has further expanded the range of glycosylation events capable of modulating Notch signaling. The prominent role of Notch during development and in later cell-fate decisions underscores the importance of these modifications in human biology. The role of glycans in intercellular signaling events is only beginning to be understood and appears ready to expand into new areas with the discovery that thrombospondin type 1 repeats are also modified with O-fucose glycans. Finally, a rare form of glycosylation called C-mannosylation modifies tryptophans in some signaling competent molecules and may be a further layer of complexity in the field. We will review each of these areas focusing on the glycan structures produced, the consequence of their presence, and the enzymes responsible.
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Affiliation(s)
- Kelvin B Luther
- Department of Biochemistry and Cell Biology, Institute for Cell and Developmental Biology, Stony Brook University, Stony Brook, NY 11794-5215, USA
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40
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Jorge AADL. [Short stature investigation: clinical, laboratorial and genetic aspects concerning the growth hormone insensitivity (GHI)]. ARQUIVOS BRASILEIROS DE ENDOCRINOLOGIA E METABOLOGIA 2008; 52:1056-65. [PMID: 18820818 DOI: 10.1590/s0004-27302008000600018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2008] [Accepted: 04/28/2008] [Indexed: 11/22/2022]
Abstract
It is reported in this study the clinical, laboratory and genetic aspects of short stature investigation with emphasis to the diagnostic approach of growth hormone insensitivity (GHI). This patient in case presented typical clinical features of GHI and his laboratory findings at prepubertal age were typical of those observed in GHI patients (low IGF-1 and IGFBP-3 levels, with high basal and stimulated GH levels). However, during the puberty, he presented normal IGFBP-3 and IGF-1 levels that hindered the diagnosis. The molecular study disclosed a mutation in exon 7 of growth hormone receptor gene (S226I). The steps that demonstrated the causative effect of this mutation are shown here, and also a review of Brazilian GHI cases is given and new molecular defects in this field are discussed as well.
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Affiliation(s)
- Alexander Augusto de Lima Jorge
- Laboratório de Hormônios e Genética Molecular- LIM/42, Disciplina de Endocrinologia do Departamento de Clínica Médica do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, SP, Brasil.
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41
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Thomas R, Yamada E, Alter G, Martin MP, Bashirova AA, Norman PJ, Altfeld M, Parham P, Anderson SK, McVicar DW, Carrington M. Novel KIR3DL1 alleles and their expression levels on NK cells: convergent evolution of KIR3DL1 phenotype variation? THE JOURNAL OF IMMUNOLOGY 2008; 180:6743-50. [PMID: 18453594 DOI: 10.4049/jimmunol.180.10.6743] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
KIR3DL1 shows extensive polymorphism, and its variation has functional significance in terms of cell-surface expression levels and inhibitory capacity. We characterized nine KIR3DL1 alleles (*022, *028, *029, *033, *035, *051, *052, *053, and *054), four of which were identified for the first time in this study, and compared them to known alleles in phylogenetic analysis. Blood was available from eight individuals with these alleles, and cell-surface expression on NK cells could be determined for six of them using the KIR3DL1-specific Ab DX9. Four of the alleles were expressed at clearly detectable levels, and two others showed exceptionally low levels of expression. Site-directed mutagenesis demonstrated that single amino acid changes can result in either diminished or enhanced DX9 staining compared with the respective related KIR3DL1 allotypes. These results raise the possibility that KIR3DL1 evolution maintains variation in KIR3DL1 cell-surface expression levels, potentially due to the effect of such variation on functional capacity.
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Affiliation(s)
- Rasmi Thomas
- Cancer and Inflammation Program, Laboratory of Experimental Immunology, National Cancer Institute, Frederick, MD 21702, USA
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A transplanted NPVY sequence in the cytosolic domain of the erythropoietin receptor enhances maturation. Biochem J 2008; 410:409-16. [PMID: 17995455 DOI: 10.1042/bj20071297] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Activation of the EPO-R [EPO (erythropoietin) receptor] by its ligand EPO promotes erythropoiesis. Low cell surface EPO-R levels are traditionally attributed to inefficient folding mediated by the receptor extracellular domain. In the present study, we addressed the role of the EPO-R intracellular domain in exit from the ER (endoplasmic reticulum) and surface expression. A fusion protein between the thermo-reversible folding mutant of VSVG (vesicular-stomatitis-virus glycoprotein) (VSVGtsO45) and the EPO-R cytosolic domain [VSVG-WT (wild-type)] displayed delayed intracellular trafficking as compared with the parental VSVGtsO45, suggesting that the EPO-R cytosolic domain can hamper ER exit. Although NPXY-based motifs were originally associated with clathrin binding and endocytosis, they may also function in other contexts of the secretory pathway. A fusion protein between VSVGtsO45 and the cytosolic portion of EPO-R containing an NPVY insert (VSVG-NPVY) displayed enhanced glycan maturation and surface expression as compared with VSVG-WT. Notably, the NPVY insert also conferred improved maturation and augmented cell surface EPO-R. Our findings highlight three major concepts: (i) the EPO-R cytosolic domain is involved in ER exit of the receptor. (ii) Sequence motifs that participate in endocytosis can also modulate transport along the secretory pathway. (iii) VSVG-fusion proteins may be employed to screen for intracellular sequences that regulate transport.
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43
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Ravid O, Shams I, Ben Califa N, Nevo E, Avivi A, Neumann D. An extracellular region of the erythropoietin receptor of the subterranean blind mole rat Spalax enhances receptor maturation. Proc Natl Acad Sci U S A 2007; 104:14360-5. [PMID: 17724331 PMCID: PMC1964849 DOI: 10.1073/pnas.0706777104] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Erythropoietic functions of erythropoietin (EPO) are mediated by its receptor (EPO-R), which is present on the cell surface of erythroid progenitors and induced by hypoxia. We focused on EPO-R from Spalax galili (sEPO-R), one of the four Israeli species of the subterranean blind mole rat, Spalax ehrenbergi superspecies, as a special natural animal model of high tolerance to hypoxia. Led by the intriguing observation that most of the mouse EPO-R (mEPO-R) is retained in the endoplasmic reticulum (ER), we hypothesized that sEPO-R is expressed at higher levels on the cell surface, thus maximizing the response to elevated EPO, which has been reported in this species. Indeed, we found increased cell-surface levels of sEPO-R as compared with mEPO-R by using flow cytometry analysis of BOSC cells transiently expressing HA-tagged EPO-Rs (full length or truncated). We then postulated that unique extracellular sEPO-R sequence features contribute to its processing and cell-surface expression. To map these domains of the sEPO-R that augment receptor maturation, we generated EPO-R derivatives in which parts of the extracellular region of mEPO-R were replaced with the corresponding fragments of sEPO-R. We found that an extracellular portion of sEPO-R, harboring the N-glycosylation site, conferred enhanced maturation and increased transport to the cell surface of the respective chimeric receptor. Taken together, we demonstrate higher surface expression of sEPO-R, attributed at least in part to increased ER exit, mediated by an extracellular region of this receptor. We speculate that these sEPO-R sequence features play a role in the adaptation of Spalax to extreme hypoxia.
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Affiliation(s)
- Orly Ravid
- *Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel-Aviv University, Ramat-Aviv 69978, Tel Aviv, Israel; and
| | - Imad Shams
- Laboratory for Animal Molecular Evolution, Institute of Evolution, University of Haifa, Mount Carmel, Haifa 31905, Israel
| | - Nathalie Ben Califa
- *Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel-Aviv University, Ramat-Aviv 69978, Tel Aviv, Israel; and
| | - Eviatar Nevo
- Laboratory for Animal Molecular Evolution, Institute of Evolution, University of Haifa, Mount Carmel, Haifa 31905, Israel
- To whom correspondence may be addressed. E-mail: , , or
| | - Aaron Avivi
- *Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel-Aviv University, Ramat-Aviv 69978, Tel Aviv, Israel; and
- To whom correspondence may be addressed. E-mail: , , or
| | - Drorit Neumann
- *Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel-Aviv University, Ramat-Aviv 69978, Tel Aviv, Israel; and
- To whom correspondence may be addressed. E-mail: , , or
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44
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Falzarano D, Krokhin O, Van Domselaar G, Wolf K, Seebach J, Schnittler HJ, Feldmann H. Ebola sGP--the first viral glycoprotein shown to be C-mannosylated. Virology 2007; 368:83-90. [PMID: 17659315 PMCID: PMC7103365 DOI: 10.1016/j.virol.2007.06.015] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2007] [Revised: 04/27/2007] [Accepted: 06/06/2007] [Indexed: 11/18/2022]
Abstract
Mass spectrometry analysis of the Ebola virus soluble glycoprotein sGP identified a rare post-translation modification, C-mannosylation, which was found on tryptophan (W) 288. This modification has not been described for any other viral protein; however, many viral transmembrane glycoproteins contain one or more of the recognition motifs (W-x-x-W). Elimination of the C-mannose on sGP did not significantly alter protein biosynthesis, processing or structure. Furthermore, the protective effect of sGP on endothelial barrier function, currently the only known activity of sGP, was unaltered. It is possible that C-mannosylation may be a common post-translational modification of viral transmembrane glycoproteins where it could play a role in particle maturation and/or entry by stabilizing the structure of these proteins. In this regard, C-mannosylation of sGP may be an anomaly resulting from the unique manner in which this protein is generated as the product of unedited transcripts from the glycoprotein gene of Ebola.
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Affiliation(s)
- Darryl Falzarano
- Department of Medical Microbiology, University of Manitoba, Winnipeg, Manitoba, Canada R3E 0W3
- Special Pathogens Program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada R3E 3R2
| | - Oleg Krokhin
- Manitoba Centre for Proteomics and Systems Biology, Winnipeg, Manitoba, Canada R3E 3P4
| | - Gary Van Domselaar
- Bioinformatics Core, National Microbiology Laboratory, Pubic Health Agency of Canada, Winnipeg, Manitoba, Canada R3E 3R2
| | - Kristin Wolf
- Institut für Physiologie, Technische-Universität Dresden, 01307 Dresden, Germany
| | - Jochen Seebach
- Institut für Physiologie, Technische-Universität Dresden, 01307 Dresden, Germany
| | | | - Heinz Feldmann
- Department of Medical Microbiology, University of Manitoba, Winnipeg, Manitoba, Canada R3E 0W3
- Special Pathogens Program, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada R3E 3R2
- Corresponding author. Special Pathogens Program, National Microbiology Laboratory, 1015 Arlington St., Winnipeg, Manitoba, Canada R3E 3R2. Fax: +1 204 789 2140.
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45
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VandenBussche CJ, Dakshanamurthy S, Posch PE, Hurley CK. A single polymorphism disrupts the killer Ig-like receptor 2DL2/2DL3 D1 domain. THE JOURNAL OF IMMUNOLOGY 2007; 177:5347-57. [PMID: 17015720 DOI: 10.4049/jimmunol.177.8.5347] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Genetic polymorphisms found in the killer Ig-like receptor (KIR), two domains, long cytoplasmic tail 2/3 (KIR2DL2/3) locus are responsible for the differential binding of KIR2DL2/3 allelic products with their HLA-C ligands and have been associated with the resolution of hepatitis C infection. In our study, a KIR CD3zeta fusion-binding assay did not detect any interaction between the KIR2DL2*004 extracellular domain and several putative KIR2DL2/3 ligands. To determine the amino acid polymorphism(s) responsible for the KIR2DL2*004 phenotype, we mutated the polymorphic residues of full-length KIR and expressed them in human Jurkat cells. Flow cytometry analysis failed to detect the surface expression of receptors containing a threonine at position 41 (T41), a polymorphism specific to KIR2DL2*004. Confocal microscopy showed that receptors containing T41 were retained inside the cell and had a perinuclear localization, possibly indicating that their extracellular domain was misfolded. Most KIR2DL2/3 alleles possess an arginine at position 41 (R41), and we predicted through molecular modeling and demonstrated by mutagenesis that R41 most likely interacts with the nearby residues Y77 and D47. Interaction between these residues would maintain C strand contact with the C' and F strands of the D1 domain beta-sheet. Furthermore, R41 and Y77 are conserved in the C and F strand amino acid alignments of Ig-like superfamily members, and may therefore be necessary for the structural integrity of other immune response proteins. Our data indicate that the extracellular T41 polymorphism encoded by the KIR2DL2*004 allele most likely results in misfolding of the D1 domain and complete intracellular retention of the receptor.
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46
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Weidemann T, Höfinger S, Müller K, Auer M. Beyond dimerization: a membrane-dependent activation model for interleukin-4 receptor-mediated signalling. J Mol Biol 2006; 366:1365-73. [PMID: 17223132 DOI: 10.1016/j.jmb.2006.11.095] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2006] [Revised: 11/27/2006] [Accepted: 11/28/2006] [Indexed: 10/23/2022]
Abstract
Class I cytokine receptors efficiently transfer activation signals from the extracellular space to the cytoplasm and play a dominant role in growth control and differentiation of human tissues. Although a significant body of literature is devoted to this topic, a consistent mechanistic picture for receptor activation in the membrane environment is still missing. Using the interleukin-4 receptor (IL-4R) as an example, we propose that the membrane-proximal stem-loop of the extracellular domains contains pivotal elements of a rotational switch. Interfacial energies of amino acid side-chains contained in the highly conserved WSXWS at the surface of the lipid bilayer suggest a new functional role for this motif. A generic activation mechanism for this receptor class is presented, which may impact the design of a new generation of biophysical assay systems.
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Affiliation(s)
- Thomas Weidemann
- Innovative Screening Technologies, Novartis Institutes for BioMedical Research, Brunnerstr 59, A-1235 Vienna, Austria.
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47
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McInnes CJ, Deane D, Haig D, Percival A, Thomson J, Wood AR. Glycosylation, disulfide bond formation, and the presence of a WSXWS-like motif in the orf virus GIF protein are critical for maintaining the integrity of Binding to ovine granulocyte-macrophage colony-stimulating factor and interleukin-2. J Virol 2005; 79:11205-13. [PMID: 16103172 PMCID: PMC1193636 DOI: 10.1128/jvi.79.17.11205-11213.2005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Orf virus (ORFV), the type species of the family Parapoxviridae, encodes a protein (GIF) that binds and inhibits the ovine cytokines granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-2 (IL-2). There is no obvious sequence homology between the ORFV protein and any known mammalian GM-CSF- or IL-2-binding proteins. We demonstrate here that many of the biochemical properties of mammalian GM-CSF receptors that are required for efficient binding of GM-CSF are also critical to the GIF protein for binding to ovine GM-CSF (ovGM-CSF). Site-directed mutagenesis of the GIF protein demonstrated, first, the importance of disulfide bonds, and second, that a sequence motif (WDPWV), related to the WSXWS motif of the type 1 cytokine receptor superfamily, was necessary for biological activity. Finally, glycosylation of the GIF protein was also critical for binding to GM-CSF.
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Affiliation(s)
- C J McInnes
- Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, Scotland, UK.
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48
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Li JS, Cui L, Rock DL, Li J. Novel glycosidic linkage in Aedes aegypti chorion peroxidase: N-mannosyl tryptophan. J Biol Chem 2005; 280:38513-21. [PMID: 16150691 DOI: 10.1074/jbc.m508449200] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Aedes aegypti chorion peroxidase (CPO) plays a crucial role in chorion hardening by catalyzing chorion protein cross-linking through dityrosine formation. The enzyme is extremely resistant to denaturing conditions, which seem intimately related to its post-translational modifications, including disulfide bond formation and glycosylation. In this report, we have provided data that describe a new type of glycosylation in CPO, where a mannose is linked to the N-1 atom of the indole ring of Trp residue. Through liquid chromatography/electrospray ionization/tandem mass spectrometry and de novo sequencing of CPO tryptic peptides, we determined that three of the seven available Trp residues in mature CPO are partially (40-50%) or completely mannosylated. This conclusion is based on the following properties of the electrospray ionization/tandem mass spectrometry spectra and the enzymatic reaction of these peptides: 1) the presence of a 162-Da substituent in each Trp residue; 2) the presence of abundant fragments of m/z 163 ([Hex + H]) and [M + H - 162] (typical for N-glycosides); 3) the absence of a loss of 120 Da (this loss is typical for aromatic C-glycosides); and 4) the cleavage of the glycosidic linkage by PNGase A or F (typical for N-glycans). These results establish that a C-N bond is formed between the anomeric carbon of a mannose residue and the N-1 atom of the indole ring of Trp. This is the first report that provides definitive evidence for N-mannosylation of Trp residues in a protein. In addition, our data demonstrate that PNGase can hydrolyze Trp N-linked mannose in peptides, which is unusual because no typical beta-amide bond is present in the Trp-mannosyl moiety. Results of this study should stimulate research toward a comprehensive understanding of physiology and biochemistry of Trp N-mannosylation in proteins and the overall biochemical mechanisms of PNGase-catalyzed reactions.
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Affiliation(s)
- Junsuo S Li
- Department of Pathobiology, University of Illinois, Urbana, Illinois 61802, USA
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49
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Pletnev S, Magracheva E, Wlodawer A, Zdanov A. A model of the ternary complex of interleukin-10 with its soluble receptors. BMC STRUCTURAL BIOLOGY 2005; 5:10. [PMID: 15985167 PMCID: PMC1192808 DOI: 10.1186/1472-6807-5-10] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/01/2005] [Accepted: 06/28/2005] [Indexed: 12/21/2022]
Abstract
BACKGROUND Interleukin-10 (IL-10) is a cytokine whose main biological function is to suppress the immune response by induction of a signal(s) leading to inhibition of synthesis of a number of cytokines and their cellular receptors. Signal transduction is initiated upon formation of a ternary complex of IL-10 with two of its receptor chains, IL-10R1 and IL-10R2, expressed on the cell membrane. The affinity of IL-10R1 toward IL-10 is very high, which allowed determination of the crystal structure of IL-10 complexed with the extracellular/soluble domain of IL-10R1, while the affinity of IL-10R2 toward either IL-10 or IL-10/sIL-10R1 complex is quite low. This so far has prevented any attempts to obtain structural information about the ternary complex of IL-10 with its receptor chains. RESULTS Structures of the second soluble receptor chain of interleukin-10 (sIL-10R2) and the ternary complex of IL-10/sIL-10R1/sIL-10R2 have been generated by homology modeling, which allowed us to identify residues involved in ligand-receptor and receptor-receptor interactions. CONCLUSION The previously experimentally determined structure of the intermediate/binary complex IL-10/sIL-10R1 is the same in the ternary complex. There are two binding sites for the second receptor chain on the surface of the IL-10/sIL-10R1 complex, involving both IL-10 and sIL-10R1. Most of the interactions are hydrophilic in nature, although each interface includes two internal hydrophobic clusters. The distance between C-termini of the receptor chains is 25 A, which is common for known structures of ternary complexes of other cytokines. The structure is likely to represent the biologically active signaling complex of IL-10 with its receptor on the surface of the cell membrane.
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MESH Headings
- Amino Acid Sequence
- Binding Sites
- Cell Line, Tumor
- Cell Membrane/metabolism
- Crystallography, X-Ray
- Gene Deletion
- Glycosylation
- Humans
- Hydrogen Bonding
- Interleukin-10/chemistry
- Ligands
- Models, Biological
- Models, Molecular
- Molecular Sequence Data
- Peptides/chemistry
- Protein Binding
- Protein Conformation
- Protein Structure, Secondary
- Protein Structure, Tertiary
- Receptors, Interferon/chemistry
- Receptors, Interleukin/chemistry
- Receptors, Interleukin-10
- Sequence Homology, Amino Acid
- Signal Transduction
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Affiliation(s)
- Sergei Pletnev
- Macromolecular Crystallography Laboratory, Center for Cancer Research, National Cancer Institute at Frederick, Frederick, MD21702-1201, USA
| | - Eugenia Magracheva
- Macromolecular Crystallography Laboratory, Center for Cancer Research, National Cancer Institute at Frederick, Frederick, MD21702-1201, USA
- Basic Research Program, Science Application International Corporation-Frederick, National Cancer Institute at Frederick, Frederick, MD21702-1201, USA
| | - Alexander Wlodawer
- Macromolecular Crystallography Laboratory, Center for Cancer Research, National Cancer Institute at Frederick, Frederick, MD21702-1201, USA
| | - Alexander Zdanov
- Macromolecular Crystallography Laboratory, Center for Cancer Research, National Cancer Institute at Frederick, Frederick, MD21702-1201, USA
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50
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Pando MJ, Gardiner CM, Gleimer M, McQueen KL, Parham P. The Protein Made from a Common Allele ofKIR3DL1(3DL1*004) Is Poorly Expressed at Cell Surfaces due to Substitution at Positions 86 in Ig Domain 0 and 182 in Ig Domain 1. THE JOURNAL OF IMMUNOLOGY 2003; 171:6640-9. [PMID: 14662867 DOI: 10.4049/jimmunol.171.12.6640] [Citation(s) in RCA: 166] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
KIR3DL1 is an inhibitory HLA-B receptor of human NK and T cells that exhibits genetic and phenotypic polymorphism. KIR3DL1*004, a common allotype, cannot be detected on the surface of PBLs using the KIR3DL1-specific Ab DX9. The nature of this phenotype was investigated through comparison of 3DL1*004 with 3DL1*002, an allele giving high DX9 binding to cell surfaces. Analysis of Jurkat T cell transfectants with 3DL1*004 cDNA showed that 3DL1*004 is poorly expressed at the cell surface, but detectable intracellularly. Analysis of recombinant mutants made between 3DL1*004 and 3DL1*002 showed that polymorphism in Ig domains 0 and 1 (D0 and D1) causes the intracellular retention of 3DL1*004. Reciprocal point mutations were introduced into 3DL1*004 and 3DL1*002 at positions 44 and 86 of the D0 domain, where 3DL1*004 has unique residues, and at position 182 of the D1 domain, where 3DL1*004 resembles 3DL1*005, an allotype giving low DX9-binding phenotype. Leucine 86 in 3DL1*004 is the principal cause of its intracellular retention, with a secondary and additive contribution from serine 182. By contrast, glycine 44, which is naturally present in 3DL1*004, slightly increased cell surface expression when introduced into 3DL1*002. In 3DL1*004, the presence of leucine at position 86 corrupts the WSXPS motif implicated in proper folding of the KIR D0 Ig-like domain. This study demonstrates how a difference between KIR3DL1 allotypes in the D0 domain profoundly affects cell surface expression and function.
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MESH Headings
- Alleles
- Amino Acid Substitution/genetics
- Amino Acid Substitution/immunology
- Cell Line
- Cell Membrane/genetics
- Cell Membrane/immunology
- Cell Membrane/metabolism
- Clone Cells
- Endoplasmic Reticulum/chemistry
- Endoplasmic Reticulum/genetics
- Endoplasmic Reticulum/immunology
- Extracellular Space/chemistry
- Extracellular Space/genetics
- Extracellular Space/immunology
- Humans
- Immunoglobulins/chemistry
- Immunoglobulins/genetics
- Immunophenotyping
- Jurkat Cells
- Killer Cells, Natural/immunology
- Killer Cells, Natural/metabolism
- Leucine/chemistry
- Leucine/genetics
- Polymorphism, Genetic/immunology
- Protein Structure, Tertiary/genetics
- Receptors, Immunologic/antagonists & inhibitors
- Receptors, Immunologic/biosynthesis
- Receptors, Immunologic/chemistry
- Receptors, Immunologic/genetics
- Receptors, KIR
- Receptors, KIR3DL1
- Serine/chemistry
- Serine/genetics
- Transfection
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Affiliation(s)
- Marcelo J Pando
- Department of Structural Biology, Stanford University School of Medicine, Stanford, CA 94305-5126, USA
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