1
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Doultsinos D, Carlesso A, Chintha C, Paton JC, Paton AW, Samali A, Chevet E, Eriksson LA. Peptidomimetic-based identification of FDA-approved compounds inhibiting IRE1 activity. FEBS J 2020; 288:945-960. [PMID: 32446294 DOI: 10.1111/febs.15372] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 04/06/2020] [Accepted: 05/19/2020] [Indexed: 12/16/2022]
Abstract
Inositol-requiring enzyme 1 (IRE1) is a bifunctional serine/threonine kinase and endoribonuclease that is a major mediator of the unfolded protein response (UPR) during endoplasmic reticulum (ER) stress. Tumour cells experience ER stress due to adverse environmental cues such as hypoxia or nutrient shortage and high metabolic/protein-folding demand. To cope with those stresses, cancer cells utilise IRE1 signalling as an adaptive mechanism. Here, we report the discovery of the FDA-approved compounds methotrexate, cefoperazone, folinic acid and fludarabine phosphate as IRE1 inhibitors. These were identified through a structural exploration of the IRE1 kinase domain using IRE1 peptide fragment docking and further optimisation and pharmacophore development. The inhibitors were verified to have an impact on IRE1 activity in vitro and were tested for their ability to sensitise human cell models of glioblastoma multiforme (GBM) to chemotherapy. We show that all molecules identified sensitise glioblastoma cells to the standard-of-care chemotherapy temozolomide (TMZ).
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Affiliation(s)
- Dimitrios Doultsinos
- Proteostasis & Cancer Team INSERM U1242 'Chemistry, Oncogenesis Stress Signaling', Université de Rennes, France.,Centre de Lutte contre le Cancer Eugène Marquis, Rennes, France
| | - Antonio Carlesso
- Department of Chemistry and Molecular Biology, University of Gothenburg, Sweden
| | - Chetan Chintha
- Apoptosis Research Centre, School of Natural Sciences, NUI Galway, Ireland
| | - James C Paton
- Research Centre for Infectious Diseases, Department of Molecular and Biomedical Science, University of Adelaide, SA, Australia
| | - Adrienne W Paton
- Research Centre for Infectious Diseases, Department of Molecular and Biomedical Science, University of Adelaide, SA, Australia
| | - Afshin Samali
- Apoptosis Research Centre, School of Natural Sciences, NUI Galway, Ireland
| | - Eric Chevet
- Proteostasis & Cancer Team INSERM U1242 'Chemistry, Oncogenesis Stress Signaling', Université de Rennes, France.,Centre de Lutte contre le Cancer Eugène Marquis, Rennes, France
| | - Leif A Eriksson
- Department of Chemistry and Molecular Biology, University of Gothenburg, Sweden
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2
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da Silva DC, Valentão P, Andrade PB, Pereira DM. Endoplasmic reticulum stress signaling in cancer and neurodegenerative disorders: Tools and strategies to understand its complexity. Pharmacol Res 2020; 155:104702. [PMID: 32068119 DOI: 10.1016/j.phrs.2020.104702] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 02/10/2020] [Accepted: 02/13/2020] [Indexed: 12/12/2022]
Abstract
The endoplasmic reticulum (ER) comprises a network of tubules and vesicles that constitutes the largest organelle of the eukaryotic cell. Being the location where most proteins are synthesized and folded, it is crucial for the upkeep of cellular homeostasis. Disturbed ER homeostasis triggers the activation of a conserved molecular machinery, termed the unfolded protein response (UPR), that comprises three major signaling branches, initiated by the protein kinase RNA-like endoplasmic reticulum kinase (PERK), inositol-requiring enzyme 1 (IRE1) and the activating transcription factor 6 (ATF6). Given the impact of this intricate signaling network upon an extensive list of cellular processes, including protein turnover and autophagy, ER stress is involved in the onset and progression of multiple diseases, including cancer and neurodegenerative disorders. There is, for this reason, an increasing number of publications focused on characterizing and/or modulating ER stress, which have resulted in a wide array of techniques employed to study ER-related molecular events. This review aims to sum up the essentials on the current knowledge of the molecular biology of endoplasmic reticulum stress, while highlighting the available tools used in studies of this nature.
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Affiliation(s)
- Daniela Correia da Silva
- REQUIMTE/LAQV, Laboratório de Farmacognosia, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-213, Porto, Portugal
| | - Patrícia Valentão
- REQUIMTE/LAQV, Laboratório de Farmacognosia, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-213, Porto, Portugal
| | - Paula B Andrade
- REQUIMTE/LAQV, Laboratório de Farmacognosia, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-213, Porto, Portugal
| | - David M Pereira
- REQUIMTE/LAQV, Laboratório de Farmacognosia, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, Rua de Jorge Viterbo Ferreira, 228, 4050-213, Porto, Portugal.
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3
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Strietz J, Stepputtis SS, Preca BT, Vannier C, Kim MM, Castro DJ, Au Q, Boerries M, Busch H, Aza-Blanc P, Heynen-Genel S, Bronsert P, Kuster B, Stickeler E, Brabletz T, Oshima RG, Maurer J. ERN1 and ALPK1 inhibit differentiation of bi-potential tumor-initiating cells in human breast cancer. Oncotarget 2018; 7:83278-83293. [PMID: 27829216 PMCID: PMC5347769 DOI: 10.18632/oncotarget.13086] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2016] [Accepted: 10/21/2016] [Indexed: 12/21/2022] Open
Abstract
Cancers are heterogeneous by nature. While traditional oncology screens commonly use a single endpoint of cell viability, altering the phenotype of tumor-initiating cells may reveal alternative targets that regulate cellular growth by processes other than apoptosis or cell division. We evaluated the impact of knocking down expression of 420 kinases in bi-lineage triple-negative breast cancer (TNBC) cells that express characteristics of both myoepithelial and luminal cells. Knockdown of ERN1 or ALPK1 induces bi-lineage MDA-MB-468 cells to lose the myoepithelial marker keratin 5 but not the luminal markers keratin 8 and GATA3. In addition, these cells exhibit increased β-casein production. These changes are associated with decreased proliferation and clonogenicity in spheroid cultures and anchorage-independent growth assays. Confirmation of these assays was completed in vivo, where ERN1- or ALPK1-deficient TNBC cells are less tumorigenic. Finally, treatment with K252a, a kinase inhibitor active on ERN1, similarly impairs anchorage-independent growth of multiple breast cancer cell lines. This study supports the strategy to identify new molecular targets for types of cancer driven by cells that retain some capacity for normal differentiation to a non-tumorigenic phenotype. ERN1 and ALPK1 are potential targets for therapeutic development.
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Affiliation(s)
- Juliane Strietz
- Department of Visceral Surgery, University Hospital Freiburg, German Cancer Consortium (DKTK), Freiburg, Germany
| | - Stella S Stepputtis
- Department of Visceral Surgery, University Hospital Freiburg, German Cancer Consortium (DKTK), Freiburg, Germany.,German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Bogdan-Tiberius Preca
- Department of Visceral Surgery, University Hospital Freiburg, German Cancer Consortium (DKTK), Freiburg, Germany.,German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Corinne Vannier
- Department of Visceral Surgery, University Hospital Freiburg, German Cancer Consortium (DKTK), Freiburg, Germany.,German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Mihee M Kim
- Institute of Pathology, University Medical Center Freiburg, Freiburg, Germany
| | - David J Castro
- Institute of Pathology, University Medical Center Freiburg, Freiburg, Germany
| | - Qingyan Au
- Institute of Pathology, University Medical Center Freiburg, Freiburg, Germany
| | - Melanie Boerries
- German Cancer Research Center (DKFZ), Heidelberg, Germany.,Systems Biology of the Cellular Microenvironment at The DKFZ Partner Site Freiburg, German Cancer Consortium (DKTK), Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Hauke Busch
- German Cancer Research Center (DKFZ), Heidelberg, Germany.,Systems Biology of the Cellular Microenvironment at The DKFZ Partner Site Freiburg, German Cancer Consortium (DKTK), Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Pedro Aza-Blanc
- Institute of Pathology, University Medical Center Freiburg, Freiburg, Germany
| | | | - Peter Bronsert
- Department of Surgical Pathology, University Medical Center Freiburg, Freiburg, Germany.,German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), Heidelberg, Germany.,Institute of Pathology, University Medical Center Freiburg, Freiburg, Germany
| | - Bernhard Kuster
- Technische Universitaet Muenchen, Partner Site of the German Cancer Consortium, Freising, Germany
| | - Elmar Stickeler
- Department of OBGYN, University Clinic Aachen (UKA), Aachen, Germany
| | - Thomas Brabletz
- Department of Experimental Medicine I, University of Erlangen-Nuernberg, Erlangen, Germany
| | - Robert G Oshima
- Institute of Pathology, University Medical Center Freiburg, Freiburg, Germany
| | - Jochen Maurer
- Institute of Pathology, University Medical Center Freiburg, Freiburg, Germany
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4
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Abstract
Autophosphorylation of kinases influences their conformational state and can also regulate enzymatic activity. Recently, this has become an area of interest for drug discovery. Using Alk2 as an example, we present two protocols - one based on phosphate-binding Alphascreen beads, the other on coupled luminescence measurements of ADP formation - that can be used to screen for inhibitors of autophosphorylation.
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Affiliation(s)
- Bianca Heedmann
- Center for Proteomic Chemistry, Novartis Institute for Biomedical Research Basel, Novartis Pharma AG, Postfach, CH-4002, Basel, Switzerland
| | - Martin Klumpp
- Center for Proteomic Chemistry, Novartis Institute for Biomedical Research Basel, Novartis Pharma AG, Postfach, CH-4002, Basel, Switzerland.
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5
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Tagit O, Hildebrandt N. Fluorescence Sensing of Circulating Diagnostic Biomarkers Using Molecular Probes and Nanoparticles. ACS Sens 2017; 2:31-45. [PMID: 28722447 DOI: 10.1021/acssensors.6b00625] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The interplay of photonics, nanotechnology, and biochemistry has significantly improved the identification and characterization of multiple types of biomarkers by optical biosensors. Great achievements in fluorescence-based technologies have been realized, for example, by the advancement of multiplexing techniques or the introduction of nanoparticles to biochemical and clinical research. This review presents a concise overview of recent advances in fluorescence sensing techniques for the detection of circulating disease biomarkers. Detection principles of representative approaches, including fluorescence detection using molecular fluorophores, quantum dots, and metallic and silica nanoparticles, are explained and illustrated by pertinent examples from the recent literature. Advanced detection technologies and material development play a major role in modern biosensing and consistently provide significant improvements toward robust, sensitive, and versatile platforms for early detection of circulating diagnostic biomarkers.
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Affiliation(s)
- Oya Tagit
- NanoBioPhotonics
(nanofret.com), Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, Université Paris-Sud, CNRS, CEA, 91405 Orsay, France
- Department
of Tumor Immunology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6500 HB Nijmegen, The Netherlands
| | - Niko Hildebrandt
- NanoBioPhotonics
(nanofret.com), Institute for Integrative Biology of the Cell (I2BC), Université Paris-Saclay, Université Paris-Sud, CNRS, CEA, 91405 Orsay, France
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6
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Pluquet O, Dejeans N, Bouchecareilh M, Lhomond S, Pineau R, Higa A, Delugin M, Combe C, Loriot S, Cubel G, Dugot-Senant N, Vital A, Loiseau H, Gosline SJC, Taouji S, Hallett M, Sarkaria JN, Anderson K, Wu W, Rodriguez FJ, Rosenbaum J, Saltel F, Fernandez-Zapico ME, Chevet E. Posttranscriptional regulation of PER1 underlies the oncogenic function of IREα. Cancer Res 2013; 73:4732-43. [PMID: 23752693 DOI: 10.1158/0008-5472.can-12-3989] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Growing evidence supports a role for the unfolded protein response (UPR) in carcinogenesis; however, the precise molecular mechanisms underlying this phenomenon remain elusive. Herein, we identified the circadian clock PER1 mRNA as a novel substrate of the endoribonuclease activity of the UPR sensor IRE1α. Analysis of the mechanism shows that IRE1α endoribonuclease activity decreased PER1 mRNA in tumor cells without affecting PER1 gene transcription. Inhibition of IRE1α signaling using either siRNA-mediated silencing or a dominant-negative strategy prevented PER1 mRNA decay, reduced tumorigenesis, and increased survival, features that were reversed upon PER1 silencing. Clinically, patients showing reduced survival have lower levels of PER1 mRNA expression and increased splicing of XBP1, a known IRE-α substrate, thereby pointing toward an increased IRE1α activity in these patients. Hence, we describe a novel mechanism connecting the UPR and circadian clock components in tumor cells, thereby highlighting the importance of this interplay in tumor development.
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Affiliation(s)
- Olivier Pluquet
- Inserm U1053, University of Bordeaux, 146 rue Leo Saignat, 33076 Bordeaux Cedex, France
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7
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Maurel M, Dejeans N, Taouji S, Chevet E, Grosset CF. MicroRNA-1291-mediated silencing of IRE1α enhances Glypican-3 expression. RNA (NEW YORK, N.Y.) 2013; 19:778-788. [PMID: 23598528 PMCID: PMC3683912 DOI: 10.1261/rna.036483.112] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Accepted: 03/06/2013] [Indexed: 06/02/2023]
Abstract
MicroRNAs (miRNA) are generally described as negative regulators of gene expression. However, some evidence suggests that they may also play positive roles. As such, we reported that miR-1291 leads to a GPC3 mRNA expression increase in hepatoma cells through a 3' untranslated region (UTR)-dependent mechanism. In the absence of any direct interaction between miR-1291 and GPC3 mRNA, we hypothesized that miR-1291 could act by silencing a negative regulator of GPC3 mRNA expression. Based on in silico predictions and experimental validation, we demonstrate herein that miR-1291 represses the expression of the mRNA encoding the endoplasmic reticulum (ER)-resident stress sensor IRE1α by interacting with a specific site located in the 5' UTR. Moreover, we show, in vitro and in cultured cells, that IRE1α cleaves GPC3 mRNA at a 3' UTR consensus site independently of ER stress, thereby prompting GPC3 mRNA degradation. Finally, we show that the expression of a miR-1291-resistant form of IRE1α abrogates the positive effects of miR-1291 on GPC3 mRNA expression. Collectively, our data demonstrate that miR-1291 is a biologically relevant regulator of GPC3 expression in hepatoma cells and acts through silencing of the ER stress sensor IRE1α.
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Affiliation(s)
- Marion Maurel
- Groupe de Recherche sur L’Étude du Foie, Université Bordeaux Segalen, F-33000 Bordeaux, France
- Team Post-transcriptional Regulation and Liver Cancer, INSERM, U1053, F-33000 Bordeaux, France
| | - Nicolas Dejeans
- Groupe de Recherche sur L’Étude du Foie, Université Bordeaux Segalen, F-33000 Bordeaux, France
- Team Endoplasmic Reticulum Stress and Cancer, INSERM, U1053, F-33000 Bordeaux, France
| | - Saïd Taouji
- Groupe de Recherche sur L’Étude du Foie, Université Bordeaux Segalen, F-33000 Bordeaux, France
- Team Endoplasmic Reticulum Stress and Cancer, INSERM, U1053, F-33000 Bordeaux, France
| | - Eric Chevet
- Groupe de Recherche sur L’Étude du Foie, Université Bordeaux Segalen, F-33000 Bordeaux, France
- Team Endoplasmic Reticulum Stress and Cancer, INSERM, U1053, F-33000 Bordeaux, France
- CHU de Bordeaux, F-33000 Bordeaux, France
| | - Christophe F. Grosset
- Groupe de Recherche sur L’Étude du Foie, Université Bordeaux Segalen, F-33000 Bordeaux, France
- Team Post-transcriptional Regulation and Liver Cancer, INSERM, U1053, F-33000 Bordeaux, France
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8
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Newbatt Y, Hardcastle A, McAndrew PC, Strover JA, Mirza A, Morgan GJ, Burke R, Davies FE, Collins I, van Montfort RLM. Identification of Autophosphorylation Inhibitors of the Inositol-Requiring Enzyme 1 Alpha (IRE1α) by High-Throughput Screening Using a DELFIA Assay. ACTA ACUST UNITED AC 2012; 18:298-308. [DOI: 10.1177/1087057112465647] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Inositol-requiring enzyme 1 alpha (IRE1α) is a transmembrane sensor protein with both kinase and ribonuclease activity, which plays a crucial role in the unfolded protein response (UPR). Protein misfolding in the endoplasmic reticulum (ER) lumen triggers dimerization and subsequent trans-autophosphorylation of IRE1α. This leads to the activation of its endoribonuclease (RNase) domain and splicing of the mRNA of the transcriptional activator XBP1, ultimately generating an active XBP1 (XBP1s) implicated in multiple myeloma survival. Previously, we have identified human IRE1α as a target for the development of kinase inhibitors that could modulate the UPR in human cells, which has particular relevance for multiple myeloma and other secretory malignancies. Here we describe the development and validation of a 384-well high-throughput screening assay using DELFIA technology that is specific for IRE1α autophosphorylation. Using this format, a focused library of 2312 potential kinase inhibitors was screened, and several novel IRE1α kinase inhibitor scaffolds were identified that could potentially be developed toward new therapies to treat multiple myeloma.
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Affiliation(s)
- Yvette Newbatt
- Division of Cancer Therapeutics, The Institute of Cancer Research, Sutton, Surrey, UK
| | - Anthea Hardcastle
- Division of Cancer Therapeutics, The Institute of Cancer Research, Sutton, Surrey, UK
| | - P. Craig McAndrew
- Division of Cancer Therapeutics, The Institute of Cancer Research, Sutton, Surrey, UK
| | - Jade A. Strover
- Division of Cancer Therapeutics, The Institute of Cancer Research, Sutton, Surrey, UK
- Division of Molecular Pathology, The Institute of Cancer Research, Sutton, Surrey, UK
| | - Amin Mirza
- Division of Cancer Therapeutics, The Institute of Cancer Research, Sutton, Surrey, UK
| | - Gareth J. Morgan
- Division of Molecular Pathology, The Institute of Cancer Research, Sutton, Surrey, UK
| | - Rosemary Burke
- Division of Cancer Therapeutics, The Institute of Cancer Research, Sutton, Surrey, UK
| | - Faith E. Davies
- Division of Molecular Pathology, The Institute of Cancer Research, Sutton, Surrey, UK
| | - Ian Collins
- Division of Cancer Therapeutics, The Institute of Cancer Research, Sutton, Surrey, UK
| | - Rob L. M. van Montfort
- Division of Cancer Therapeutics, The Institute of Cancer Research, Sutton, Surrey, UK
- Division of Structural Biology, The Institute of Cancer Research, London, UK
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9
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Bouchecareilh M, Higa A, Fribourg S, Moenner M, Chevet E. Peptides derived from the bifunctional kinase/RNase enzyme IRE1α modulate IRE1α activity and protect cells from endoplasmic reticulum stress. FASEB J 2011; 25:3115-29. [DOI: 10.1096/fj.11-182931] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Marion Bouchecareilh
- Institut National de la Santé et de la Recherche Médicale (INSERM)U1053, AvenirBordeauxFrance
- Université Bordeaux SegalenBordeauxFrance
- INSERMTalenceFrance
- Université BordeauxTalenceFrance
| | - Arisa Higa
- Institut National de la Santé et de la Recherche Médicale (INSERM)U1053, AvenirBordeauxFrance
| | - Sébastien Fribourg
- Université Bordeaux SegalenBordeauxFrance
- Institut Européen de Chimie et de BiologieBordeauxFrance
| | | | - Eric Chevet
- Institut National de la Santé et de la Recherche Médicale (INSERM)U1053, AvenirBordeauxFrance
- Inserm U1053Avenir, Université Bordeaux 2146 rue Léo Saignat33076BordeauxFrance
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10
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Dausse E, Taouji S, Evadé L, Di Primo C, Chevet E, Toulmé JJ. HAPIscreen, a method for high-throughput aptamer identification. J Nanobiotechnology 2011; 9:25. [PMID: 21639912 PMCID: PMC3127992 DOI: 10.1186/1477-3155-9-25] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2011] [Accepted: 06/03/2011] [Indexed: 01/24/2023] Open
Abstract
Background Aptamers are oligonucleotides displaying specific binding properties for a predetermined target. They are selected from libraries of randomly synthesized candidates through an in vitro selection process termed SELEX (Systematic Evolution of Ligands by EXponential enrichment) alternating selection and amplification steps. SELEX is followed by cloning and sequencing of the enriched pool of oligonucleotides to enable comparison of the selected sequences. The most represented candidates are then synthesized and their binding properties are individually evaluated thus leading to the identification of aptamers. These post-selection steps are time consuming and introduce a bias to the expense of poorly amplified binders that might be of high affinity and are consequently underrepresented. A method that would circumvent these limitations would be highly valuable. Results We describe a novel homogeneous solution-based method for screening large populations of oligonucleotide candidates generated from SELEX. This approach, based on the AlphaScreen® technology, is carried out on the exclusive basis of the binding properties of the selected candidates without the needs of performing a priori sequencing. It therefore enables the functional identification of high affinity aptamers. We validated the HAPIscreen (High throughput APtamer Identification screen) methodology using aptamers targeted to RNA hairpins, previously identified in our laboratory. We then screened pools of candidates issued from SELEX rounds in a 384 well microplate format and identify new RNA aptamers to pre-microRNAs. Conclusions HAPIscreen, an Alphascreen®-based methodology for the identification of aptamers is faster and less biased than current procedures based on sequence comparison of selected oligonucleotides and sampling binding properties of few individuals. Moreover this methodology allows for screening larger number of candidates. Used here for selecting anti-premiR aptamers, HAPIscreen can be adapted to any type of tagged target and is fully amenable to automation.
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Affiliation(s)
- Eric Dausse
- Inserm U869, Institut Européen de Chimie et Biologie, 2 rue Robert Escarpit, 33706 Pessac, France
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11
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Chang CF, Pan JF, Lin CN, Wu IL, Wong CH, Lin CH. Rapid characterization of sugar-binding specificity by in-solution proximity binding with photosensitizers. Glycobiology 2011; 21:895-902. [PMID: 21325337 DOI: 10.1093/glycob/cwr021] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Cell-surface carbohydrates are known to participate in many important physiological and pathological activities by interacting with their corresponding proteins or receptors. Although several methods have been developed for studying carbohydrate-protein interactions, one major problem originates from the weak bindings of carbohydrates/proteins that are often lost during repeating wash steps. Herein, we established a homogeneous solution carbohydrate array in which polyacrylamide-based glycans are used for offering a multivalent environment. The method requires no wash step and can be carried out in a high-throughput manner. We characterized the carbohydrate-binding specificities of 11 lectins and 7 antibodies, the majority of which displayed the binding patterns in consistence with previous reports. These results demonstrate that our developed solution carbohydrate array provides a useful alternative that is better than or comparable with the current available methods.
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Affiliation(s)
- Chuan-Fa Chang
- Department of Medical Laboratory Science and Biotechnology, National Taiwan University, Taipei
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