1
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Heating-mediated purification of active FGF21 and structure-based design of its variant with enhanced potency. Sci Rep 2023; 13:1005. [PMID: 36653390 PMCID: PMC9849446 DOI: 10.1038/s41598-023-27717-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 01/06/2023] [Indexed: 01/20/2023] Open
Abstract
Fibroblast growth factor 21 (FGF21) has pharmaceutical potential against obesity-related metabolic disorders, including non-alcoholic fatty liver disease. Since thermal stability is a desirable factor for therapeutic proteins, we investigated the thermal behavior of human FGF21. FGF21 remained soluble after heating; thus, we examined its temperature-induced structural changes using circular dichroism (CD). FGF21 showed inter-convertible temperature-specific CD spectra. The CD spectrum at 100 °C returned to that at 20 °C when the heated FGF21 solution was cooled. Through loop swapping, the connecting loop between β10 and β12 in FGF21 was revealed to be associated with the unique thermal behavior of FGF21. According to surface plasmon resonance (SPR) experiments, in vitro cell-based assays, and model high-fat diet (HFD)-induced obesity studies, heated FGF21 maintained biological activities that were comparable to those of non-heated and commercial FGF21s. Based on sequence comparison and structural analysis, five point-mutations were introduced into FGF21. Compared with the wild type, the heated FGF21 variant displayed improved therapeutic potential in terms of body weight loss, the levels of hepatic triglycerides and lipids, and the degree of vacuolization of liver in HFD-fed mice.
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2
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Schenkel M, Treff A, Deber CM, Krainer G, Schlierf M. Heat treatment of thioredoxin fusions increases the purity of α-helical transmembrane protein constructs. Protein Sci 2021; 30:1974-1982. [PMID: 34191368 PMCID: PMC8376418 DOI: 10.1002/pro.4150] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Accepted: 06/22/2021] [Indexed: 01/05/2023]
Abstract
Membrane proteins play key roles in cellular signaling and transport, represent the majority of drug targets, and are implicated in many diseases. Their relevance renders them important subjects for structural, biophysical, and functional investigations. However, obtaining membrane proteins in high purities is often challenging with conventional purification steps alone. To address this issue, we present here an approach to increase the purity of α-helical transmembrane proteins. Our approach exploits the Thioredoxin (Trx) tag system, which is able to confer some of its favorable properties, such as high solubility and thermostability, to its fusion partners. Using Trx fusions of transmembrane helical hairpin constructs derived from the human cystic fibrosis transmembrane conductance regulator (CFTR) and a bacterial ATP synthase, we establish conditions for the successful implementation of the selective heat treatment procedure to increase sample purity. We further examine systematically its efficacy with respect to different incubation times and temperatures using quantitative gel electrophoresis. We find that minute-timescale heat treatment of Trx-tagged fusion constructs with temperatures ranging from 50 to 90°C increases the purity of the membrane protein samples from ~60 to 98% even after affinity purification. We show that this single-step approach is even applicable in cases where regular selective heat purification from crude extracts, as reported for Trx fusions to soluble proteins, fails. Overall, our approach is easy to integrate into existing purification strategies and provides a facile route for increasing the purity of membrane protein constructs after purification by standard chromatography approaches.
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Affiliation(s)
- Mathias Schenkel
- B CUBE – Center for Molecular BioengineeringTU DresdenDresdenGermany
| | - Antoine Treff
- B CUBE – Center for Molecular BioengineeringTU DresdenDresdenGermany
| | - Charles M. Deber
- Division of Molecular Medicine, Research InstituteHospital for Sick ChildrenTorontoOntarioCanada
| | - Georg Krainer
- B CUBE – Center for Molecular BioengineeringTU DresdenDresdenGermany
- Centre for Misfolding Diseases, Yusuf Hamied Department of ChemistryUniversity of CambridgeCambridgeUK
| | - Michael Schlierf
- B CUBE – Center for Molecular BioengineeringTU DresdenDresdenGermany
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3
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Tabakmakher VM, Gigolaev AM, Peigneur S, Krylov NA, Tytgat J, Chugunov AO, Vassilevski AA, Efremov RG. Potassium channel blocker crafted by α-hairpinin scaffold engineering. Biophys J 2021; 120:2471-2481. [PMID: 33932436 DOI: 10.1016/j.bpj.2021.04.020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 04/14/2021] [Accepted: 04/15/2021] [Indexed: 11/29/2022] Open
Abstract
The α-Hairpinins are a family of plant defense peptides with a common fold presenting two short α-helices stabilized by two invariant S-S-bridges. We have shown previously that substitution of just two amino acid residues in a wheat α-hairpinin Tk-AMP-X2 leads to Tk-hefu-2 that features specific affinity to voltage-gated potassium channels KV1.3. Here, we utilize a combined molecular modeling approach based on molecular dynamics simulations and protein surface topography technique to improve the affinity of Tk-hefu-2 to KV1.3 while preserving its specificity. An important advance of this work compared with our previous studies is transition from the analysis of various physicochemical properties of an isolated toxin molecule to its consideration in complex with its target, a membrane-bound ion channel. As a result, a panel of computationally designed Tk-hefu-2 derivatives was synthesized and tested against KV1.3. The most active mutant Tk-hefu-10 showed a half-maximal inhibitory concentration of ∼150 nM being >10 times more active than Tk-hefu-2 and >200 times more active than the original Tk-hefu. We conclude that α-hairpinins provide an attractive disulfide-stabilized scaffold for the rational design of ion channel inhibitors. Furthermore, the success rate can be considerably increased by the proposed "target-based" iterative strategy of molecular design.
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Affiliation(s)
- Valentin M Tabakmakher
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia; School of Biomedicine, Far Eastern Federal University, Vladivostok, Russia
| | - Andrei M Gigolaev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Steve Peigneur
- Toxicology and Pharmacology, University of Leuven, Leuven, Belgium
| | - Nikolay A Krylov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia; National Research University Higher School of Economics, Moscow, Russia
| | - Jan Tytgat
- Toxicology and Pharmacology, University of Leuven, Leuven, Belgium
| | - Anton O Chugunov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia; National Research University Higher School of Economics, Moscow, Russia; Moscow Institute of Physics and Technology, Moscow State University, Dolgoprudny, Moscow Oblast, Russia
| | - Alexander A Vassilevski
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia; Moscow Institute of Physics and Technology, Moscow State University, Dolgoprudny, Moscow Oblast, Russia.
| | - Roman G Efremov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia; National Research University Higher School of Economics, Moscow, Russia; Moscow Institute of Physics and Technology, Moscow State University, Dolgoprudny, Moscow Oblast, Russia
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4
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Khatiwada B, Purslow JA, Underbakke ES, Venditti V. N-terminal fusion of the N-terminal domain of bacterial enzyme I facilitates recombinant expression and purification of the human RNA demethylases FTO and Alkbh5. Protein Expr Purif 2019; 167:105540. [PMID: 31740367 DOI: 10.1016/j.pep.2019.105540] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Revised: 11/14/2019] [Accepted: 11/14/2019] [Indexed: 01/20/2023]
Abstract
Various fusion tags are commonly employed to increase the heterologous expression and solubility of aggregation-prone proteins within Escherichia coli. Herein, we present a protocol for efficient recombinant expression and purification of the human RNA demethylases Alkbh5 and FTO. Our method incorporates a novel fusion tag (the N-terminal domain of bacterial enzyme I, EIN) that dramatically increases the solubility of its fusion partner and is promptly removed upon digestion with a protease. The presented protocol allows for the production of mg amounts of Alkbh5 and FTO in 1L of both rich and minimal media. We developed a liquid chromatography-mass spectrometry (LC-MS)-based assay to confirm that both proteins are enzymatically active. Furthermore, the LC-MS method developed here is applicable to other members of the AlkB family of Fe(II)/α-ketoglutarate-dependent dioxygenases. The superior protein yield, afforded by our expression and purification method, will facilitate biochemical investigations into the biological function of the human RNA demethylases and endorse employment of EIN as a broadly applicable fusion tag for recombinant expression projects.
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Affiliation(s)
| | - Jeffrey A Purslow
- Department of Chemistry, Iowa State University, Ames, IA, 50011, USA
| | - Eric S Underbakke
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA, 50011, USA
| | - Vincenzo Venditti
- Department of Chemistry, Iowa State University, Ames, IA, 50011, USA; Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA, 50011, USA.
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5
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A minimal helical-hairpin motif provides molecular-level insights into misfolding and pharmacological rescue of CFTR. Commun Biol 2018; 1:154. [PMID: 30302398 PMCID: PMC6162264 DOI: 10.1038/s42003-018-0153-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 08/24/2018] [Indexed: 12/11/2022] Open
Abstract
Our meagre understanding of CFTR misfolding and its reversal by small-molecule correctors hampers the development of mechanism-based therapies of cystic fibrosis. Here we exploit a helical-hairpin construct—the simplest proxy of membrane-protein tertiary contacts—containing CFTR’s transmembrane helices 3 and 4 and its corresponding disease phenotypic mutant V232D to gain molecular-level insights into CFTR misfolding and drug rescue by the corrector Lumacaftor. Using a single-molecule FRET approach to study hairpin conformations in lipid bilayers, we find that the wild-type hairpin is well folded, whereas the V232D mutant assumes an open conformation in bilayer thicknesses mimicking the endoplasmic reticulum. Addition of Lumacaftor reverses the aberrant opening of the mutant hairpin to restore a compact state as in the wild type. The observed membrane escape of the V232D hairpin and its reversal by Lumacaftor complement cell-based analyses of the full-length protein, thereby providing in vivo and in vitro correlates of CFTR misfolding and drug-action mechanisms. Georg Krainer and Antoine Treff et al. use a helical-hairpin construct derived from the cystic fibrosis transmembrane conductance regulator (CFTR) to investigate misfolding caused by the disease-linked V232D mutation. Using single-molecule FRET, they show that the V232D hairpin assumes an open conformation in lipid bilayers, which is reversed by the pharmacological corrector Lumacaftor.
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6
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Bule P, Alves VD, Leitão A, Ferreira LMA, Bayer EA, Smith SP, Gilbert HJ, Najmudin S, Fontes CMGA. Single Binding Mode Integration of Hemicellulose-degrading Enzymes via Adaptor Scaffoldins in Ruminococcus flavefaciens Cellulosome. J Biol Chem 2016; 291:26658-26669. [PMID: 27875311 PMCID: PMC5207176 DOI: 10.1074/jbc.m116.761643] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 11/08/2016] [Indexed: 11/06/2022] Open
Abstract
The assembly of one of Nature's most elaborate multienzyme complexes, the cellulosome, results from the binding of enzyme-borne dockerins to reiterated cohesin domains located in a non-catalytic primary scaffoldin. Generally, dockerins present two similar cohesin-binding interfaces that support a dual binding mode. The dynamic integration of enzymes in cellulosomes, afforded by the dual binding mode, is believed to incorporate additional flexibility in highly populated multienzyme complexes. Ruminococcus flavefaciens, the primary degrader of plant structural carbohydrates in the rumen of mammals, uses a portfolio of more than 220 different dockerins to assemble the most intricate cellulosome known to date. A sequence-based analysis organized R. flavefaciens dockerins into six groups. Strikingly, a subset of R. flavefaciens cellulosomal enzymes, comprising dockerins of groups 3 and 6, were shown to be indirectly incorporated into primary scaffoldins via an adaptor scaffoldin termed ScaC. Here, we report the crystal structure of a group 3 R. flavefaciens dockerin, Doc3, in complex with ScaC cohesin. Doc3 is unusual as it presents a large cohesin-interacting surface that lacks the structural symmetry required to support a dual binding mode. In addition, dockerins of groups 3 and 6, which bind exclusively to ScaC cohesin, display a conserved mechanism of protein recognition that is similar to Doc3. Groups 3 and 6 dockerins are predominantly appended to hemicellulose-degrading enzymes. Thus, single binding mode dockerins interacting with adaptor scaffoldins exemplify an evolutionary pathway developed by R. flavefaciens to recruit hemicellulases to the sophisticated cellulosomes acting in the gastrointestinal tract of mammals.
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Affiliation(s)
- Pedro Bule
- From the CIISA-Faculdade de Medicina Veterinária, ULisboa, Pólo Universitário do Alto da Ajuda, Avenida da Universidade Técnica, 1300-477 Lisboa, Portugal
| | - Victor D Alves
- From the CIISA-Faculdade de Medicina Veterinária, ULisboa, Pólo Universitário do Alto da Ajuda, Avenida da Universidade Técnica, 1300-477 Lisboa, Portugal
| | - André Leitão
- From the CIISA-Faculdade de Medicina Veterinária, ULisboa, Pólo Universitário do Alto da Ajuda, Avenida da Universidade Técnica, 1300-477 Lisboa, Portugal
| | - Luís M A Ferreira
- From the CIISA-Faculdade de Medicina Veterinária, ULisboa, Pólo Universitário do Alto da Ajuda, Avenida da Universidade Técnica, 1300-477 Lisboa, Portugal
| | - Edward A Bayer
- the Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Steven P Smith
- the Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario K7L 3N6, Canada, and
| | - Harry J Gilbert
- the Institute for Cell and Molecular Biosciences, Newcastle University Medical School, Newcastle upon Tyne NE2 4HH, United Kingdom
| | - Shabir Najmudin
- From the CIISA-Faculdade de Medicina Veterinária, ULisboa, Pólo Universitário do Alto da Ajuda, Avenida da Universidade Técnica, 1300-477 Lisboa, Portugal
| | - Carlos M G A Fontes
- From the CIISA-Faculdade de Medicina Veterinária, ULisboa, Pólo Universitário do Alto da Ajuda, Avenida da Universidade Técnica, 1300-477 Lisboa, Portugal,
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7
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Bommer M, Bondar AN, Zouni A, Dobbek H, Dau H. Crystallographic and Computational Analysis of the Barrel Part of the PsbO Protein of Photosystem II: Carboxylate–Water Clusters as Putative Proton Transfer Relays and Structural Switches. Biochemistry 2016; 55:4626-35. [DOI: 10.1021/acs.biochem.6b00441] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Martin Bommer
- Institut
für Biologie, Strukturbiologie/Biochemie, Humboldt-Universität zu Berlin, Unter den Linden 6, 10099 Berlin, Germany
| | - Ana-Nicoleta Bondar
- Fachbereich
Physik, Theoretical Molecular Biophysics, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
| | - Athina Zouni
- Institut
für Biologie, Biophysik der Photosynthese, Humboldt-Universität zu Berlin, Unter den Linden 6, 10099 Berlin, Germany
| | - Holger Dobbek
- Institut
für Biologie, Strukturbiologie/Biochemie, Humboldt-Universität zu Berlin, Unter den Linden 6, 10099 Berlin, Germany
| | - Holger Dau
- Fachbereich
Physik, Biophysics and Photosynthesis, Freie Universität Berlin, Arnimallee 14, 14195 Berlin, Germany
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8
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Zhao H, Zhou J, Zhang K, Chu H, Liu D, Poon VKM, Chan CCS, Leung HC, Fai N, Lin YP, Zhang AJX, Jin DY, Yuen KY, Zheng BJ. A novel peptide with potent and broad-spectrum antiviral activities against multiple respiratory viruses. Sci Rep 2016; 6:22008. [PMID: 26911565 PMCID: PMC4766503 DOI: 10.1038/srep22008] [Citation(s) in RCA: 104] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 02/03/2016] [Indexed: 12/19/2022] Open
Abstract
A safe, potent and broad-spectrum antiviral is urgently needed to combat emerging respiratory viruses. In light of the broad antiviral activity of β-defensins, we tested the antiviral activity of 11 peptides derived from mouse β-defensin-4 and found that a short peptide, P9, exhibited potent and broad-spectrum antiviral effects against multiple respiratory viruses in vitro and in vivo, including influenza A virus H1N1, H3N2, H5N1, H7N7, H7N9, SARS-CoV and MERS-CoV. The antiviral activity of P9 was attributed to its high-affinity binding to viral glycoproteins, as well as the abundance of basic amino acids in its composition. After binding viral particles through viral surface glycoproteins, P9 entered into cells together with the viruses via endocytosis and prevented endosomal acidification, which blocked membrane fusion and subsequent viral RNA release. This study has paved the avenue for developing new prophylactic and therapeutic agents with broad-spectrum antiviral activities.
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Affiliation(s)
- Hanjun Zhao
- Department of Microbiology, The University of Hong Kong, Hong Kong, China
| | - Jie Zhou
- Department of Microbiology, The University of Hong Kong, Hong Kong, China
| | - Ke Zhang
- Department of Microbiology, The University of Hong Kong, Hong Kong, China
| | - Hin Chu
- Department of Microbiology, The University of Hong Kong, Hong Kong, China
| | - Dabin Liu
- Department of Microbiology, The University of Hong Kong, Hong Kong, China
| | | | | | - Ho-Chuen Leung
- Department of Microbiology, The University of Hong Kong, Hong Kong, China
| | - Ng Fai
- Department of Microbiology, The University of Hong Kong, Hong Kong, China
| | - Yong-Ping Lin
- Department of Microbiology, The University of Hong Kong, Hong Kong, China
| | - Anna Jin-Xia Zhang
- Department of Microbiology, The University of Hong Kong, Hong Kong, China
| | - Dong-Yan Jin
- School of Biomedical Sciences, The University of Hong Kong, Hong Kong, China
| | - Kwok-Yung Yuen
- Department of Microbiology, The University of Hong Kong, Hong Kong, China
| | - Bo-Jian Zheng
- Department of Microbiology, The University of Hong Kong, Hong Kong, China
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9
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Soluble expression, purification and functional characterization of a coil peptide composed of a positively charged and hydrophobic motif. Amino Acids 2015; 48:567-77. [PMID: 26459292 DOI: 10.1007/s00726-015-2113-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 10/05/2015] [Indexed: 10/22/2022]
Abstract
A de novo heterodimeric coiled-coil system formed by the association of two synthetic peptides, the Ecoil and Kcoil, has been previously designed and proven to be an excellent and versatile tool for various biotechnology applications. However, based on the challenges encountered during its chemical synthesis, the Kcoil peptide has been designated as a "difficult peptide". In this study, we explore the expression of the Kcoil peptide by a bacterial system as well as its subsequent purification. The maximum expression level was observed when the peptide was fused to thioredoxin and the optimized purification process consisted of three chromatographic steps: immobilized-metal affinity chromatography followed by cation-exchange chromatography and, finally, a reverse-phase high-performance liquid chromatography. This entire process led to a final volumetric production yield of 1.5 mg of pure Kcoil peptide per liter of bacterial culture, which represents a significant step towards the cost-effective production and application of coiled-coil motifs. Our results thus demonstrate for the first time that bacterial production is a viable alternative to the chemical synthesis of de novo designed coil peptides.
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10
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Duivenvoorden WCM, Paschos A, Hopmans SN, Austin RC, Pinthus JH. Endoplasmic reticulum protein ERp46 in renal cell carcinoma. PLoS One 2014; 9:e90389. [PMID: 24594673 PMCID: PMC3940878 DOI: 10.1371/journal.pone.0090389] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Accepted: 01/28/2014] [Indexed: 11/22/2022] Open
Abstract
An established inverse clinical correlation between serum adiponectin levels and renal cell carcinoma (RCC) aggressiveness exists. We have recently demonstrated that adiponectin suppresses clear cell RCC (ccRCC) progression through interaction with its receptor, adiponectin receptor 1 (AdipoR1). ERp46 has been shown to inhibit adiponectin signaling via interaction with AdipoR1 in HeLa cells. However, the expression of ERp46 in RCC has not been described thus far. The objectives of this study were to investigate ERp46 in RCC, its expression, its effects on RCC growth in a mouse model and whether it interacts with AdipoR1. We demonstrated a higher ERp46/AdipoR1 expression ratio in metastatic compared to non-metastatic ccRCC, as determined by immunohistochemistry of tissue microarrays and subsequent image analysis. When ERp46 was stably knocked down using shRNA or overexpressed in murine RCC RAG cells, RCC growth after subcutaneous injection in BALB/c nude mice was inhibited and accelerated, respectively. In vitro analysis to determine the molecular interaction between AdipoR1 and ERp46 included co-immunoprecipitation using human ccRCC 786-O cells and a bacterial adenylate cyclase-based two hybrid system and demonstrated no sustained AdipoR1-ERp46 interaction. This is the first report to suggest a role for ERp46 as a potential therapeutic target in RCC given its expression profile in human RCC samples and its effect on in vivo RCC growth. Since a stable interaction with AdipoR1 could not be established, we suggest that the tumorigenic properties of ERp46 in RCC cells are not related to an inhibitory modulation of AdipoR1.
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Affiliation(s)
| | - Athanasios Paschos
- Department of Surgery, McMaster University and St. Joseph's Healthcare Hamilton, Hamilton, Ontario, Canada
| | - Sarah N. Hopmans
- Department of Surgery, McMaster University and St. Joseph's Healthcare Hamilton, Hamilton, Ontario, Canada
| | - Richard C. Austin
- Department of Surgery, McMaster University and St. Joseph's Healthcare Hamilton, Hamilton, Ontario, Canada
| | - Jehonathan H. Pinthus
- Department of Surgery, McMaster University and St. Joseph's Healthcare Hamilton, Hamilton, Ontario, Canada
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