1
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Clemente L, Bird IM. The epidermal growth factor receptor in healthy pregnancy and preeclampsia. J Mol Endocrinol 2023; 70:e220105. [PMID: 36197759 PMCID: PMC9742168 DOI: 10.1530/jme-22-0105] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Accepted: 10/05/2022] [Indexed: 11/09/2022]
Abstract
The epidermal growth factor receptor (EGFR) is expressed robustly in the placenta, and critical processes of pregnancy such as placental growth and trophoblast fusion are dependent on EGFR function. However, the role that aberrant EGFR signaling might play in the etiology and/or maintenance of preeclampsia (PE) remains largely unexplored. Recently, we have shown that overexpression of EGFR in cultured uterine artery endothelial cells (UAEC), which express little endogenous EGFR, remaps responsiveness away from vascular endothelial growth factor receptor (VEGFR) signaling and toward EGFR, suggesting that endothelial EGFR expression may be kept low to preserve VEGFR control of angiogenesis. Here we will consider the evidence for the possibility that the endothelial dysfunction observed in PE might in some cases result from elevation of endothelial EGFR. During pregnancy, trophoblasts are known to synthesize large amounts of EGFR protein, and the placenta regularly releases syncytiotrophoblast-derived exosomes and microparticles into the maternal circulation. Although there are no reports of elevated EGFR gene expression in preeclamptic endothelial cells, the ongoing shedding of placental vesicles into the vascular system raises the possibility that EGFR-rich vesicles might fuse with endothelium, thereby contributing to the symptoms of PE by interrupting angiogenesis and blocking pregnancy-adapted vasodilatory function.
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Affiliation(s)
- Luca Clemente
- Perinatal Research Laboratories, Department of Obstetrics and Gynecology, University of Wisconsin, School of Medicine and Public Health, Madison, WI, 53715, USA
| | - Ian M. Bird
- Perinatal Research Laboratories, Department of Obstetrics and Gynecology, University of Wisconsin, School of Medicine and Public Health, Madison, WI, 53715, USA
- Department of Pediatrics, University of Wisconsin, School of Medicine and Public Health, Madison, WI, 53715, USA
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2
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Balasubramanian H, Sankaran J, Pandey S, Goh CJH, Wohland T. The dependence of EGFR oligomerization on environment and structure: A camera-based N&B study. Biophys J 2022; 121:4452-4466. [PMID: 36335429 PMCID: PMC9748371 DOI: 10.1016/j.bpj.2022.11.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 09/30/2022] [Accepted: 11/01/2022] [Indexed: 11/06/2022] Open
Abstract
Number and brightness (N&B) analysis is a fluorescence spectroscopy technique to quantify oligomerization of the mobile fraction of proteins. Accurate results, however, rely on a good knowledge of nonfluorescent states of the fluorescent labels, especially of fluorescent proteins, which are widely used in biology. Fluorescent proteins have been characterized for confocal, but not camera-based, N&B, which allows, in principle, faster measurements over larger areas. Here, we calibrate camera-based N&B implemented on a total internal reflection fluorescence microscope for various fluorescent proteins by determining their propensity to be fluorescent. We then apply camera-based N&B in live CHO-K1 cells to determine the oligomerization state of the epidermal growth factor receptor (EGFR), a transmembrane receptor tyrosine kinase that is a crucial regulator of cell proliferation and survival with implications in many cancers. EGFR oligomerization in resting cells and its regulation by the plasma membrane microenvironment are still under debate. Therefore, we investigate the effects of extrinsic factors, including membrane organization, cytoskeletal structure, and ligand stimulation, and intrinsic factors, including mutations in various EGFR domains, on the receptor's oligomerization. Our results demonstrate that EGFR oligomerization increases with removal of cholesterol or sphingolipids or the disruption of GM3-EGFR interactions, indicating raft association. However, oligomerization is not significantly influenced by the cytoskeleton. Mutations in either I706/V948 residues or E685/E687/E690 residues in the kinase and juxtamembrane domains, respectively, lead to a decrease in oligomerization, indicating their necessity for EGFR dimerization. Finally, EGFR phosphorylation is oligomerization dependent, involving the extracellular domain (550-580 residues). Coupled with biochemical investigations, camera-based N&B indicates that EGFR oligomerization and phosphorylation are the outcomes of several molecular interactions involving the lipid content and structure of the cell membrane and multiple residues in the kinase, juxtamembrane, and extracellular domains.
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Affiliation(s)
- Harikrushnan Balasubramanian
- Department of Biological Sciences and NUS Centre for Bio-Imaging Sciences, National University of Singapore, Singapore, Singapore
| | - Jagadish Sankaran
- Department of Biological Sciences and NUS Centre for Bio-Imaging Sciences, National University of Singapore, Singapore, Singapore
| | - Shambhavi Pandey
- Department of Biological Sciences and NUS Centre for Bio-Imaging Sciences, National University of Singapore, Singapore, Singapore
| | - Corinna Jie Hui Goh
- Department of Biological Sciences and NUS Centre for Bio-Imaging Sciences, National University of Singapore, Singapore, Singapore
| | - Thorsten Wohland
- Department of Biological Sciences and NUS Centre for Bio-Imaging Sciences, National University of Singapore, Singapore, Singapore; Department of Chemistry, National University of Singapore, Singapore, Singapore.
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3
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Matsuzaki K. Elucidation of Complex Dynamic Intermolecular Interactions in Membranes. Chem Pharm Bull (Tokyo) 2022; 70:1-9. [PMID: 34980725 DOI: 10.1248/cpb.c21-00815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Biomembranes composed of various proteins and lipids play important roles in cellular functions, such as signal transduction and substance transport. In addition, some bioactive peptides and pathogenic proteins target membrane proteins and lipids to exert their effects. Therefore, an understanding of dynamic and complex intermolecular interactions among these membrane constituents is needed to elucidate their mechanisms. This review summarizes the major research carried out in the author's laboratory on how lipids and their inhomogeneous distributions regulate the structures and functions of antimicrobial peptides and Alzheimer's amyloid β-protein. Also, how to detect transmembrane helix-helix and membrane protein-protein interactions and how they are modulated by lipids are discussed.
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4
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Wolf P, Gavins G, Beck‐Sickinger AG, Seitz O. Strategies for Site-Specific Labeling of Receptor Proteins on the Surfaces of Living Cells by Using Genetically Encoded Peptide Tags. Chembiochem 2021; 22:1717-1732. [PMID: 33428317 PMCID: PMC8248378 DOI: 10.1002/cbic.202000797] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 01/08/2021] [Indexed: 12/14/2022]
Abstract
Fluorescence microscopy imaging enables receptor proteins to be investigated within their biological context. A key challenge is to site-specifically incorporate reporter moieties into proteins without interfering with biological functions or cellular networks. Small peptide tags offer the opportunity to combine inducible labeling with small tag sizes that avoid receptor perturbation. Herein, we review the current state of live-cell labeling of peptide-tagged cell-surface proteins. Considering their importance as targets in medicinal chemistry, we focus on membrane receptors such as G protein-coupled receptors (GPCRs) and receptor tyrosine kinases (RTKs). We discuss peptide tags that i) are subject to enzyme-mediated modification reactions, ii) guide the complementation of reporter proteins, iii) form coiled-coil complexes, and iv) interact with metal complexes. Given our own contributions in the field, we place emphasis on peptide-templated labeling chemistry.
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Affiliation(s)
- Philipp Wolf
- Faculty of Life SciencesInstitute of BiochemistryLeipzig UniversityBrüderstrasse 3404103LeipzigGermany
| | - Georgina Gavins
- Faculty of Mathematics and Natural SciencesDepartment of ChemistryHumboldt-Universität zu BerlinBrook-Taylor-Str. 212489BerlinGermany
| | - Annette G. Beck‐Sickinger
- Faculty of Life SciencesInstitute of BiochemistryLeipzig UniversityBrüderstrasse 3404103LeipzigGermany
| | - Oliver Seitz
- Faculty of Mathematics and Natural SciencesDepartment of ChemistryHumboldt-Universität zu BerlinBrook-Taylor-Str. 212489BerlinGermany
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5
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Nakano M, Hanashima S, Hara T, Kabayama K, Asahina Y, Hojo H, Komura N, Ando H, Nyholm TKM, Slotte JP, Murata M. FRET detects lateral interaction between transmembrane domain of EGF receptor and ganglioside GM3 in lipid bilayers. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2021; 1863:183623. [PMID: 33933428 DOI: 10.1016/j.bbamem.2021.183623] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 04/03/2021] [Accepted: 04/05/2021] [Indexed: 12/16/2022]
Abstract
Ganglioside GM3 in the plasma membranes suppresses cell growth by preventing the autophosphorylation of the epidermal growth factor receptor (EGFR). Biological studies have suggested that GM3 interacts with the transmembrane segment of EGFR. Further biophysical experiments are particularly important for quantitative evaluation of the peptide-glycolipid interplay in bilayer membranes using a simple reconstituted system. To examine these interactions in this way, we synthesized the transmembrane segment of EGFR bearing a nitrobenzoxadiazole fluorophore (NBD-TM) at the N-terminus. The affinity between EGFR and GM3 was evaluated based on Förster resonance energy transfer (FRET) between NBD-TM and ATTO594-labeled GM3 in bilayers where their non-specific interaction due to lateral proximity was subtracted by using NBD-labeled phospholipid. This method for selectively detecting the specific lipid-peptide interactions in model lipid bilayers disclosed that the lateral interaction between GM3 and the transmembrane segment of EGFR plays a certain role in disturbing the formation of active EGFR dimers.
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Affiliation(s)
- Mikito Nakano
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan
| | - Shinya Hanashima
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan.
| | - Toshiaki Hara
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan; ERATO, Lipid Active Structure Project, Japan Science and Technology Agency, Graduate School of Science, Osaka University, Osaka 560-0043, Japan
| | - Kazuya Kabayama
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan
| | - Yuya Asahina
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita 565-0871, Japan
| | - Hironobu Hojo
- Institute for Protein Research, Osaka University, Yamadaoka 3-2, Suita 565-0871, Japan
| | - Naoko Komura
- Center for Highly Advanced Integration of Nano and Life Sciences (G-CHAIN), Gifu University, Gifu 501-1193, Japan; Institute for Glyco-core Research (iGCORE), Gifu University, Gifu 501-1193, Japan
| | - Hiromune Ando
- Center for Highly Advanced Integration of Nano and Life Sciences (G-CHAIN), Gifu University, Gifu 501-1193, Japan; Institute for Glyco-core Research (iGCORE), Gifu University, Gifu 501-1193, Japan
| | - Thomas K M Nyholm
- Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, 20520 Turku, Finland
| | - J Peter Slotte
- Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, 20520 Turku, Finland
| | - Michio Murata
- Department of Chemistry, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan; ERATO, Lipid Active Structure Project, Japan Science and Technology Agency, Graduate School of Science, Osaka University, Osaka 560-0043, Japan.
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6
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Yano Y, Matsuzaki K. Live-cell imaging of membrane proteins by a coiled-coil labeling method-Principles and applications. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2019; 1861:1011-1017. [PMID: 30831076 DOI: 10.1016/j.bbamem.2019.02.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 02/18/2019] [Accepted: 02/27/2019] [Indexed: 02/09/2023]
Abstract
In situ investigations in living cell membranes are important to elucidate the dynamic behaviors of membrane proteins in complex biomembrane environments. Protein-specific labeling is a key technique for the detection of a target protein by fluorescence imaging. The use of post-translational labeling methods using a genetically encodable tag and synthetic probes targeting the tag offer a smaller label size, labeling with synthetic fluorophores, and precise control of the labeling ratio in multicolor labeling compared with conventional genetic fusions with fluorescent proteins. This review focuses on tag-probe labeling studies for live-cell analysis of membrane proteins based on heterodimeric peptide pairs that form coiled-coil structures. The robust and simple peptide-peptide interaction enables not only labeling of membrane proteins by noncovalent interactions, but also covalent crosslinking and acyl transfer reactions guided by coiled-coil assembly. A number of studies have demonstrated that membrane protein behaviors in live cells, such as internalization of receptors and the oligomeric states of various membrane proteins (G-protein-coupled receptors, epidermal growth factor receptors, influenza A M2 channel, and glycopholin A), can be precisely analyzed using coiled-coil labeling, indicating the potential of this labeling method in membrane protein research.
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Affiliation(s)
- Yoshiaki Yano
- Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida-Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
| | - Katsumi Matsuzaki
- Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida-Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan.
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7
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Yano Y, Matsuzaki K. [Fluorescent Peptide Tools for Studying the Self-association of Membrane Proteins]. YAKUGAKU ZASSHI 2019; 139:273-276. [PMID: 30713239 DOI: 10.1248/yakushi.18-00174-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Detecting the behaviors of proteins in membranes is often challenging; we need to develop new methods to better understand the mechanisms involved. We have developed two types of peptide-based experimental systems that can detect the self-association of proteins in bilayer environments: 1) a single-pair fluorescence detection system for studying the self-association of transmembrane helices in model membranes; and 2) live-cell fluorescence labeling and analysis of the oligomeric state of membrane proteins using a coiled-coil labeling method. By using these methods, we show that membrane cholesterol significantly affects the self-association of transmembrane helices.
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Affiliation(s)
- Yoshiaki Yano
- Department of Biophysical Chemistry, Graduate School of Pharmaceutical Sciences, Kyoto University
| | - Katsumi Matsuzaki
- Department of Biophysical Chemistry, Graduate School of Pharmaceutical Sciences, Kyoto University
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8
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Yan Q, Cai M, Zhou L, Xu H, Shi Y, Sun J, Jiang J, Gao J, Wang H. Using an RNA aptamer probe for super-resolution imaging of native EGFR. NANOSCALE ADVANCES 2019; 1:291-298. [PMID: 36132464 PMCID: PMC9473275 DOI: 10.1039/c8na00143j] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2018] [Revised: 01/08/2019] [Accepted: 08/16/2018] [Indexed: 05/06/2023]
Abstract
Aptamers, referred to as "chemical antibodies", are short single-stranded oligonucleotides that bind to targets with high affinity and specificity. Compared with antibodies, aptamers can be designed, developed and modified easily. Since their discovery, aptamers have been widely used in in vitro diagnostics and molecular imaging. However, they are relatively less studied and applied in advanced microscopy. Here we used an RNA aptamer in dSTORM imaging and obtained a high-quality image of EGFR nanoscale clusters on live cell membranes. The results showed that the cluster number and size with aptamer labeling were almost the same as those with labeling with the natural ligand EGF, but the morphology of the clusters was smaller and more regular than that with cetuximab labeling. Meanwhile, dual-color imaging demonstrated sufficient fluorophore labeling, highly specific recognition and greatly accurate clustering information provided by aptamers. Furthermore, the aptamer labeling method indicated that active EGFR formed larger clusters containing more molecules than resting EGFR, which was hidden under the antibody labeling. Our work suggested that aptamers can be used as versatile probes in super-resolution imaging with small steric hindrance, opening a new avenue for detailed and precise morphological analysis of membrane proteins.
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Affiliation(s)
- Qiuyan Yan
- State Key Laboratory of Electroanalytical Chemistry, Research Center of Biomembranomics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences Changchun Jilin 130022 P. R. China
- University of Chinese Academy of Sciences Beijing 100049 P. R. China
| | - Mingjun Cai
- State Key Laboratory of Electroanalytical Chemistry, Research Center of Biomembranomics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences Changchun Jilin 130022 P. R. China
| | - Lulu Zhou
- State Key Laboratory of Electroanalytical Chemistry, Research Center of Biomembranomics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences Changchun Jilin 130022 P. R. China
- University of Chinese Academy of Sciences Beijing 100049 P. R. China
| | - Haijiao Xu
- State Key Laboratory of Electroanalytical Chemistry, Research Center of Biomembranomics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences Changchun Jilin 130022 P. R. China
- University of Chinese Academy of Sciences Beijing 100049 P. R. China
| | - Yan Shi
- State Key Laboratory of Electroanalytical Chemistry, Research Center of Biomembranomics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences Changchun Jilin 130022 P. R. China
| | - Jiayin Sun
- State Key Laboratory of Electroanalytical Chemistry, Research Center of Biomembranomics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences Changchun Jilin 130022 P. R. China
| | - Junguang Jiang
- State Key Laboratory of Electroanalytical Chemistry, Research Center of Biomembranomics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences Changchun Jilin 130022 P. R. China
| | - Jing Gao
- State Key Laboratory of Electroanalytical Chemistry, Research Center of Biomembranomics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences Changchun Jilin 130022 P. R. China
| | - Hongda Wang
- State Key Laboratory of Electroanalytical Chemistry, Research Center of Biomembranomics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences Changchun Jilin 130022 P. R. China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology Wenhai Road, Aoshanwei, Jimo, Qingdao Shandong 266237 P. R. China
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9
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Rink WM, Thomas F. De Novo Designed α-Helical Coiled-Coil Peptides as Scaffolds for Chemical Reactions. Chemistry 2018; 25:1665-1677. [DOI: 10.1002/chem.201802849] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Indexed: 01/31/2023]
Affiliation(s)
- W. Mathis Rink
- Institute of Organic and Biomolecular Chemistry; Georg-August-Universität Göttingen; Tammannstraße 2 37077 Göttingen Germany
| | - Franziska Thomas
- Institute of Organic and Biomolecular Chemistry; Georg-August-Universität Göttingen; Tammannstraße 2 37077 Göttingen Germany
- Center for Biostructural Imaging of Neurodegeneration; Von-Siebold-Straße 3a 37075 Göttingen Germany
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10
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Mitchell RA, Luwor RB, Burgess AW. Epidermal growth factor receptor: Structure-function informing the design of anticancer therapeutics. Exp Cell Res 2018; 371:1-19. [PMID: 30098332 DOI: 10.1016/j.yexcr.2018.08.009] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 07/30/2018] [Accepted: 08/01/2018] [Indexed: 12/19/2022]
Abstract
Research on the epidermal growth factor (EGF) family and the family of receptors (EGFR) has progressed rapidly in recent times. New crystal structures of the ectodomains with different ligands, the activation of the kinase domain through oligomerisation and the use of fluorescence techniques have revealed profound conformational changes on ligand binding. The control of cell signaling from the EGFR-family is complex, with heterodimerisation, ligand affinity and signaling cross-talk influencing cellular outcomes. Analysis of tissue homeostasis indicates that the control of pro-ligand processing is likely to be as important as receptor activation events. Several members of the EGFR-family are overexpressed and/or mutated in cancer cells. The perturbation of EGFR-family signaling drives the malignant phenotype of many cancers and both inhibitors and antagonists of signaling from these receptors have already produced therapeutic benefits for patients. The design of affibodies, antibodies, small molecule inhibitors and even immunotherapeutic drugs targeting the EGFR-family has yielded promising new approaches to improving outcomes for cancer patients. In this review, we describe recent discoveries which have increased our understanding of the structure and dynamics of signaling from the EGFR-family, the roles of ligand processing and receptor cross-talk. We discuss the relevance of these studies to the development of strategies for designing more effective targeted treatments for cancer patients.
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Affiliation(s)
- Ruth A Mitchell
- Structural Biology Division, The Walter and Eliza Hall Institute of Medical Research, Victoria 3052, Australia; Department of Surgery, The University of Melbourne, The Royal Melbourne Hospital, Parkville, Victoria 3050, Australia
| | - Rodney B Luwor
- Department of Surgery, The University of Melbourne, The Royal Melbourne Hospital, Parkville, Victoria 3050, Australia
| | - Antony W Burgess
- Structural Biology Division, The Walter and Eliza Hall Institute of Medical Research, Victoria 3052, Australia; Department of Surgery, The University of Melbourne, The Royal Melbourne Hospital, Parkville, Victoria 3050, Australia.
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11
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Zhang M, Zhang Z, He K, Wu J, Li N, Zhao R, Yuan J, Xiao H, Zhang Y, Fang X. Quantitative Characterization of the Membrane Dynamics of Newly Delivered TGF-β Receptors by Single-Molecule Imaging. Anal Chem 2018; 90:4282-4287. [PMID: 29509006 DOI: 10.1021/acs.analchem.7b03448] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The dynamics and stoichiometry of receptors newly delivered on the plasma membrane play a vital role in cell signal transduction, yet knowledge of this process is limited because of the lack of suitable analytical methods. Here we developed a new strategy that combines single-molecule imaging (SMI) and fluorescence recovery after photobleaching (FRAP), named FRAP-SMI, to monitor and quantify individual newly delivered and inserted transmembrane receptors on plasma membranes of living cells. Transforming-growth-factor-β type II receptor (TβRII), a typical serine/threoninekinase receptor, was studied with this method. We first eliminated the fluorescence signals from the pre-existing EGFP-labeled TβRII molecules on the plasma membrane, and then we recorded the individual newly appeared TβRII-GFP by total-internal-reflection fluorescence imaging. The fluorescence-intensity distributions, photobleaching steps, and diffusion rates of the single TβRII-GFP molecules were analyzed. We reported, for the first time, that TβRII was transported to the plasma membrane mainly in the monomeric form in both resting and TGF-β1stimulated cells. This strongly supported our former discovery that TβRII could exist as a monomer on the cell membrane. We also found that ligand stimulation resulted in enhanced delivery rates and prolonged membrane-association times for the TβRII molecules. On the basis of these observations, we proposed a mechanism of TGF-β1-induced TβRII dimerization for receptor activation. Our method provides a useful tool for the real-time quantification of the spatial arrangement, mobility, and oligomerization of cell-surface proteins in living cells, thus providing a better understanding of cell signaling.
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Affiliation(s)
- Mingliang Zhang
- Institute of Vascular Medicine of Third Hospital, Ministry of Health Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides, Beijing Key Laboratory of Cardiovascular Receptors and Academy for Advanced Interdisciplinary Studies , Peking University , Beijing 100191 , P. R. China.,CAS Research/Education Center for Excellence in Molecular Sciences, Key Laboratory of Molecular Nanostructures and Nanotechnology, Institute of Chemistry , Chinese Academy of Sciences , Beijing 100190 , P. R. China
| | - Zhen Zhang
- CAS Research/Education Center for Excellence in Molecular Sciences, Key Laboratory of Molecular Nanostructures and Nanotechnology, Institute of Chemistry , Chinese Academy of Sciences , Beijing 100190 , P. R. China.,University of Chinese Academy of Sciences , Beijing 100049 , P. R. China
| | - Kangmin He
- Institute of Vascular Medicine of Third Hospital, Ministry of Health Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides, Beijing Key Laboratory of Cardiovascular Receptors and Academy for Advanced Interdisciplinary Studies , Peking University , Beijing 100191 , P. R. China.,CAS Research/Education Center for Excellence in Molecular Sciences, Key Laboratory of Molecular Nanostructures and Nanotechnology, Institute of Chemistry , Chinese Academy of Sciences , Beijing 100190 , P. R. China
| | - Jimin Wu
- Institute of Vascular Medicine of Third Hospital, Ministry of Health Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides, Beijing Key Laboratory of Cardiovascular Receptors and Academy for Advanced Interdisciplinary Studies , Peking University , Beijing 100191 , P. R. China
| | - Nan Li
- CAS Research/Education Center for Excellence in Molecular Sciences, Key Laboratory of Molecular Nanostructures and Nanotechnology, Institute of Chemistry , Chinese Academy of Sciences , Beijing 100190 , P. R. China.,University of Chinese Academy of Sciences , Beijing 100049 , P. R. China
| | - Rong Zhao
- CAS Research/Education Center for Excellence in Molecular Sciences, Key Laboratory of Molecular Nanostructures and Nanotechnology, Institute of Chemistry , Chinese Academy of Sciences , Beijing 100190 , P. R. China.,University of Chinese Academy of Sciences , Beijing 100049 , P. R. China
| | - Jinghe Yuan
- CAS Research/Education Center for Excellence in Molecular Sciences, Key Laboratory of Molecular Nanostructures and Nanotechnology, Institute of Chemistry , Chinese Academy of Sciences , Beijing 100190 , P. R. China.,University of Chinese Academy of Sciences , Beijing 100049 , P. R. China
| | - Han Xiao
- Institute of Vascular Medicine of Third Hospital, Ministry of Health Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides, Beijing Key Laboratory of Cardiovascular Receptors and Academy for Advanced Interdisciplinary Studies , Peking University , Beijing 100191 , P. R. China
| | - Youyi Zhang
- Institute of Vascular Medicine of Third Hospital, Ministry of Health Key Laboratory of Cardiovascular Molecular Biology and Regulatory Peptides, Beijing Key Laboratory of Cardiovascular Receptors and Academy for Advanced Interdisciplinary Studies , Peking University , Beijing 100191 , P. R. China
| | - Xiaohong Fang
- CAS Research/Education Center for Excellence in Molecular Sciences, Key Laboratory of Molecular Nanostructures and Nanotechnology, Institute of Chemistry , Chinese Academy of Sciences , Beijing 100190 , P. R. China.,University of Chinese Academy of Sciences , Beijing 100049 , P. R. China
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12
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Strand Displacement in Coiled-Coil Structures: Controlled Induction and Reversal of Proximity. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201705339] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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13
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Gröger K, Gavins G, Seitz O. Strand Displacement in Coiled-Coil Structures: Controlled Induction and Reversal of Proximity. Angew Chem Int Ed Engl 2017; 56:14217-14221. [PMID: 28913864 DOI: 10.1002/anie.201705339] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 08/25/2017] [Indexed: 12/26/2022]
Abstract
Coiled-coil peptides are frequently used to create new function upon the self-assembly of supramolecular complexes. A multitude of coil peptide sequences provides control over the specificity and stability of coiled-coil complexes. However, comparably little attention has been paid to the development of methods that allow the reversal of complex formation under non-denaturing conditions. Herein, we present a reversible two-state switching system. The process involves two peptide molecules for the formation of a size-mismatched coiled-coil duplex and a third, disruptor peptide that targets an overhanging end. A real-time fluorescence assay revealed that the proximity between two chromophores can be switched on and off, repetitively if desired. Showcasing the advantages provided by non-denaturing conditions, the method permitted control over the bivalent interactions of the tSH2 domain of Syk kinase with a phosphopeptide ligand.
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Affiliation(s)
- Katharina Gröger
- Institut für Chemie der Humboldt-Universität zu Berlin, Brook-Taylor-Str. 2, 12489, Berlin, Germany
| | - Georgina Gavins
- Institut für Chemie der Humboldt-Universität zu Berlin, Brook-Taylor-Str. 2, 12489, Berlin, Germany
| | - Oliver Seitz
- Institut für Chemie der Humboldt-Universität zu Berlin, Brook-Taylor-Str. 2, 12489, Berlin, Germany
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14
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Kawano K, Yagi T, Fukada N, Yano Y, Matsuzaki K. Stoichiometric analysis of oligomeric states of three class-A GPCRs, chemokine-CXCR4, dopamine-D2, and prostaglandin-EP1 receptors, on living cells. J Pept Sci 2017. [PMID: 28626925 DOI: 10.1002/psc.3020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
G-protein-coupled receptors (GPCRs) form the largest family of transmembrane receptors, and their oligomerization has been suggested to be related to their functions. Despite extensive studies, their oligomeric states are highly controversial. One of the reasons is the overestimation of oligomerization by conventional methods. We recently established a stoichiometric analysis method for precisely determining the oligomeric state of membrane proteins on living cells with the combined use of the coiled-coil labeling method and a spectral imaging technique and showed that the prototypical class-A GPCR β2 -adrenergic receptor (β2 AR) did not form functional oligomers. In this study, we expanded our study to three well-studied class-A GPCRs: C-X-C chemokine receptor of stromal cell-derived factor-1α (CXCR4), dopamine receptor D2 short isotype (D2R), and prostaglandin E receptor subtype 1 (EP1R). We found that these receptors did not form constitutive homooligomers. The receptors exhibited calcium signaling upon agonist stimulation as monomers, although CXCR4 and EP1R gradually clustered after fast signaling. We conclude that homooligomerization is not necessary for the signal transductions of these four class-A GPCRs. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd.
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Affiliation(s)
- Kenichi Kawano
- Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida-Shimoadachicho, Sakyo-ku, Kyoto, 606-8501, Japan
| | - Tetsuya Yagi
- Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida-Shimoadachicho, Sakyo-ku, Kyoto, 606-8501, Japan
| | - Nozomu Fukada
- Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida-Shimoadachicho, Sakyo-ku, Kyoto, 606-8501, Japan
| | - Yoshiaki Yano
- Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida-Shimoadachicho, Sakyo-ku, Kyoto, 606-8501, Japan
| | - Katsumi Matsuzaki
- Graduate School of Pharmaceutical Sciences, Kyoto University, 46-29 Yoshida-Shimoadachicho, Sakyo-ku, Kyoto, 606-8501, Japan
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15
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Yavas S, Macháň R, Wohland T. The Epidermal Growth Factor Receptor Forms Location-Dependent Complexes in Resting Cells. Biophys J 2017; 111:2241-2254. [PMID: 27851946 DOI: 10.1016/j.bpj.2016.09.049] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Revised: 07/25/2016] [Accepted: 09/26/2016] [Indexed: 10/20/2022] Open
Abstract
The epidermal growth factor receptor (EGFR) is a prototypical receptor tyrosine kinase involved in cell growth and proliferation and associated with various cancers. It is commonly assumed that after activation by binding of epidermal growth factor to the extracellular domain it dimerizes, followed by autophosphorylation of tyrosine residues at the intracellular domain. However, its oligomerization state before activation is controversial. In the absence of ligands, EGFR has been found in various, inconsistent amounts of monomeric, inactive dimeric, and oligomeric forms. In addition, evidence suggests that the active conformation is not a simple dimer but contains higher oligomers. As experiments in the past have been conducted at different conditions, we investigate here the influence of cell lines (HEK293, COS-7, and CHO-K1), temperature (room temperature and 37°C), and membrane localization on the quantitation of preformed dimers using SW-FCCS, DC-FCCS, quasi PIE-FCCS, and imaging FCCS. While measurement modality, temperature, and localization on upper or lower membranes have only a limited influence on the dimerization amount observed, the cell line and location to periphery versus center of the cell can change dimerization results significantly. The observed dimerization amount is strongly dependent on the expression level of endogenous EGFR in a cell line and shows a strong cell-to-cell variability even within the same cell line. In addition, using imaging FCCS, we find that dimers have a tendency to be found at the periphery of cells compared to central positions.
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Affiliation(s)
- Sibel Yavas
- Department of Chemistry, National University of Singapore, Singapore, Singapore
| | - Radek Macháň
- Department of Biological Sciences and Centre for BioImaging Sciences, National University of Singapore, Singapore, Singapore
| | - Thorsten Wohland
- Department of Chemistry, National University of Singapore, Singapore, Singapore; Department of Biological Sciences and Centre for BioImaging Sciences, National University of Singapore, Singapore, Singapore.
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16
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Activation of the EGF Receptor by Ligand Binding and Oncogenic Mutations: The "Rotation Model". Cells 2017; 6:cells6020013. [PMID: 28574446 PMCID: PMC5492017 DOI: 10.3390/cells6020013] [Citation(s) in RCA: 103] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 05/17/2017] [Accepted: 05/31/2017] [Indexed: 01/17/2023] Open
Abstract
The epidermal growth factor receptor (EGFR) plays vital roles in cellular processes including cell proliferation, survival, motility, and differentiation. The dysregulated activation of the receptor is often implicated in human cancers. EGFR is synthesized as a single-pass transmembrane protein, which consists of an extracellular ligand-binding domain and an intracellular kinase domain separated by a single transmembrane domain. The receptor is activated by a variety of polypeptide ligands such as epidermal growth factor and transforming growth factor α. It has long been thought that EGFR is activated by ligand-induced dimerization of the receptor monomer, which brings intracellular kinase domains into close proximity for trans-autophosphorylation. An increasing number of diverse studies, however, demonstrate that EGFR is present as a pre-formed, yet inactive, dimer prior to ligand binding. Furthermore, recent progress in structural studies has provided insight into conformational changes during the activation of a pre-formed EGFR dimer. Upon ligand binding to the extracellular domain of EGFR, its transmembrane domains rotate or twist parallel to the plane of the cell membrane, resulting in the reorientation of the intracellular kinase domain dimer from a symmetric inactive configuration to an asymmetric active form (the “rotation model”). This model is also able to explain how oncogenic mutations activate the receptor in the absence of the ligand, without assuming that the mutations induce receptor dimerization. In this review, we discuss the mechanisms underlying the ligand-induced activation of the preformed EGFR dimer, as well as how oncogenic mutations constitutively activate the receptor dimer, based on the rotation model.
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17
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DE JONGE N. Membrane protein stoichiometry studied in intact mammalian cells using liquid-phase electron microscopy. J Microsc 2017; 269:134-142. [DOI: 10.1111/jmi.12570] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 03/15/2017] [Accepted: 03/25/2017] [Indexed: 02/02/2023]
Affiliation(s)
- N. DE JONGE
- Leibniz Institute for New Materials; Saarbrücken Germany
- Department of Physics; University of Saarland; Saarbrücken Germany
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18
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Bocharov EV, Mineev KS, Pavlov KV, Akimov SA, Kuznetsov AS, Efremov RG, Arseniev AS. Helix-helix interactions in membrane domains of bitopic proteins: Specificity and role of lipid environment. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2016; 1859:561-576. [PMID: 27884807 DOI: 10.1016/j.bbamem.2016.10.024] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 09/18/2016] [Accepted: 10/20/2016] [Indexed: 12/23/2022]
Abstract
Interaction between transmembrane helices often determines biological activity of membrane proteins. Bitopic proteins, a broad subclass of membrane proteins, form dimers containing two membrane-spanning helices. Some aspects of their structure-function relationship cannot be fully understood without considering the protein-lipid interaction, which can determine the protein conformational ensemble. Experimental and computer modeling data concerning transmembrane parts of bitopic proteins are reviewed in the present paper. They highlight the importance of lipid-protein interactions and resolve certain paradoxes in the behavior of such proteins. Besides, some properties of membrane organization provided a clue to understanding of allosteric interactions between distant parts of proteins. Interactions of these kinds appear to underlie a signaling mechanism, which could be widely employed in the functioning of many membrane proteins. Treatment of membrane proteins as parts of integrated fine-tuned proteolipid system promises new insights into biological function mechanisms and approaches to drug design. This article is part of a Special Issue entitled: Lipid order/lipid defects and lipid-control of protein activity edited by Dirk Schneider.
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Affiliation(s)
- Eduard V Bocharov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Miklukho-Maklaya ul. 16/10, Moscow, 117997, Russian Federation; National Research Centre "Kurchatov Institute", Akad. Kurchatova pl. 1, Moscow, 123182, Russian Federation.
| | - Konstantin S Mineev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Miklukho-Maklaya ul. 16/10, Moscow, 117997, Russian Federation
| | - Konstantin V Pavlov
- Frumkin Institute of Physical Chemistry and Electrochemistry RAS, Leninskiy prospect 31/5, Moscow, 119071, Russian Federation
| | - Sergey A Akimov
- Frumkin Institute of Physical Chemistry and Electrochemistry RAS, Leninskiy prospect 31/5, Moscow, 119071, Russian Federation; National University of Science and Technology "MISiS", Leninskiy prospect 4, Moscow, 119049, Russian Federation
| | - Andrey S Kuznetsov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Miklukho-Maklaya ul. 16/10, Moscow, 117997, Russian Federation
| | - Roman G Efremov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Miklukho-Maklaya ul. 16/10, Moscow, 117997, Russian Federation; Higher School of Economics, Myasnitskaya ul. 20, Moscow, 101000, Russian Federation
| | - Alexander S Arseniev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Miklukho-Maklaya ul. 16/10, Moscow, 117997, Russian Federation.
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19
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Liu Y, Nie L, Chen X. Photoacoustic Molecular Imaging: From Multiscale Biomedical Applications Towards Early-Stage Theranostics. Trends Biotechnol 2016; 34:420-433. [PMID: 26924233 DOI: 10.1016/j.tibtech.2016.02.001] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Revised: 01/28/2016] [Accepted: 02/01/2016] [Indexed: 10/22/2022]
Abstract
Photoacoustic imaging (PAI) has ushered in a new era of observational biotechnology and has facilitated the exploration of fundamental biological mechanisms and clinical translational applications, which has attracted tremendous attention in recent years. By converting laser into ultrasound emission, PAI combines rich optical contrast, high ultrasonic spatial resolution, and deep penetration depth in a single modality. This evolutional technique enables multiscale and multicontrast visualization from cells to organs, anatomy to function, and molecules to metabolism with high sensitivity and specificity. The state-of-the-art developments and applications of PAI are described in this review. Future prospects for clinical use are also highlighted. Collectively, PAI holds great promise to drive biomedical applications towards early-stage theranostics.
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Affiliation(s)
- Yajing Liu
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, Center for Molecular Imaging and Translational Medicine (CMITM), School of Public Health, Xiamen University, Xiamen 361102, China
| | - Liming Nie
- State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, Center for Molecular Imaging and Translational Medicine (CMITM), School of Public Health, Xiamen University, Xiamen 361102, China.
| | - Xiaoyuan Chen
- Laboratory of Molecular Imaging and Nanomedicine, National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH), Bethesda, MD 20892, USA.
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20
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Lotze J, Reinhardt U, Seitz O, Beck-Sickinger AG. Peptide-tags for site-specific protein labelling in vitro and in vivo. MOLECULAR BIOSYSTEMS 2016; 12:1731-45. [DOI: 10.1039/c6mb00023a] [Citation(s) in RCA: 129] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Peptide-tag based labelling can be achieved by (i) enzymes (ii) recognition of metal ions or small molecules and (iii) peptide–peptide interactions and enables site-specific protein visualization to investigate protein localization and trafficking.
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Affiliation(s)
- Jonathan Lotze
- Institut für Biochemie
- Universität Leipzig
- D-04103 Leipzig
- Germany
| | - Ulrike Reinhardt
- Institut für Chemie
- Humboldt-Universität zu Berlin
- D-12489 Berlin
- Germany
| | - Oliver Seitz
- Institut für Chemie
- Humboldt-Universität zu Berlin
- D-12489 Berlin
- Germany
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21
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Kwon MJ, Park J, Jang S, Eom CY, Oh ES. The Conserved Phenylalanine in the Transmembrane Domain Enhances Heteromeric Interactions of Syndecans. J Biol Chem 2015; 291:872-81. [PMID: 26601939 DOI: 10.1074/jbc.m115.685040] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Indexed: 11/06/2022] Open
Abstract
The transmembrane domain (TMD) of the syndecans, a family of transmembrane heparin sulfate proteoglycans, is involved in forming homo- and heterodimers and oligomers that transmit signaling events. Recently, we reported that the unique phenylalanine in TMD positively regulates intramolecular interactions of syndecan-2. Besides the unique phenylalanine, syndecan-2 contains a conserved phenylalanine (SDC2-Phe-169) that is present in all syndecan TMDs, but its function has not been determined. We therefore investigated the structural role of SDC2-Phe-169 in syndecan TMDs. Replacement of SDC2-Phe-169 by tyrosine (S2F169Y) did not affect SDS-resistant homodimer formation but significantly reduced SDS-resistant heterodimer formation between syndecan-2 and -4, suggesting that SDC2-Phe-169 is involved in the heterodimerization/oligomerization of syndecans. Similarly, in an in vitro binding assay, a syndecan-2 mutant (S2(F169Y)) showed a significantly reduced interaction with syndecan-4. FRET assays showed that heteromolecular interactions between syndecan-2 and -4 were reduced in HEK293T cells transfected with S2(F169Y) compared with syndecan-2. Moreover, S2(F169Y) reduced downstream reactions mediated by the heterodimerization of syndecan-2 and -4, including Rac activity, cell migration, membrane localization of PKCα, and focal adhesion formation. The conserved phenylalanine in syndecan-1 and -3 also showed heterodimeric interaction with syndecan-2 and -4. Taken together, these findings suggest that the conserved phenylalanine in the TMD of syndecans is crucial in regulating heteromeric interactions of syndecans.
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Affiliation(s)
- Mi-Jung Kwon
- From the Department of Life Sciences, Research Center for Cellular Homeostasis, Ewha Womans University, Seoul 120-750, Korea and
| | - Jisu Park
- From the Department of Life Sciences, Research Center for Cellular Homeostasis, Ewha Womans University, Seoul 120-750, Korea and
| | - Sinae Jang
- the Seoul Center, Korea Basic Science Institute, Seoul 136-075, Korea
| | - Chi-Yong Eom
- the Seoul Center, Korea Basic Science Institute, Seoul 136-075, Korea
| | - Eok-Soo Oh
- From the Department of Life Sciences, Research Center for Cellular Homeostasis, Ewha Womans University, Seoul 120-750, Korea and
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