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Chaves-Arquero B, Collins KM, Abis G, Kelly G, Christodoulou E, Taylor IA, Ramos A. Affinity-enhanced RNA-binding domains as tools to understand RNA recognition. Cell Rep Methods 2023; 3:100508. [PMID: 37426752 PMCID: PMC10326445 DOI: 10.1016/j.crmeth.2023.100508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 03/14/2023] [Accepted: 05/30/2023] [Indexed: 07/11/2023]
Abstract
Understanding how the RNA-binding domains of a protein regulator are used to recognize its RNA targets is a key problem in RNA biology, but RNA-binding domains with very low affinity do not perform well in the methods currently available to characterize protein-RNA interactions. Here, we propose to use conservative mutations that enhance the affinity of RNA-binding domains to overcome this limitation. As a proof of principle, we have designed and validated an affinity-enhanced K-homology (KH) domain mutant of the fragile X syndrome protein FMRP, a key regulator of neuronal development, and used this mutant to determine the domain's sequence preference and to explain FMRP recognition of specific RNA motifs in the cell. Our results validate our concept and our nuclear magnetic resonance (NMR)-based workflow. While effective mutant design requires an understanding of the underlying principles of RNA recognition by the relevant domain type, we expect the method will be used effectively in many RNA-binding domains.
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Affiliation(s)
- Belén Chaves-Arquero
- Institute of Structural and Molecular Biology (ISMB), University College London, London WC1E 6AA, UK
- Department of Structural and Chemical Biology, Center for Biological Research, CIB, CSIC, Av. Ramiro de Maeztu 9, 28040 Madrid, Spain
| | - Katherine M. Collins
- Institute of Structural and Molecular Biology (ISMB), University College London, London WC1E 6AA, UK
| | - Giancarlo Abis
- Institute of Structural and Molecular Biology (ISMB), University College London, London WC1E 6AA, UK
| | - Geoff Kelly
- The Medical Research Council Biomedical NMR Centre, the Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Evangelos Christodoulou
- Structural Biology Science Technology Platform, the Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Ian A. Taylor
- Macromolecular Structure Laboratory, the Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Andres Ramos
- Institute of Structural and Molecular Biology (ISMB), University College London, London WC1E 6AA, UK
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2
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Tran TN, Adler TJ, Yamlahi A, Christodoulou E, Godau P, Reinke A, Tizabi MD, Sauer P, Persicke T, Albert JG, Maier-Hein L. Sources of performance variability in deep learning-based polyp detection. Int J Comput Assist Radiol Surg 2023:10.1007/s11548-023-02936-9. [PMID: 37266886 PMCID: PMC10329574 DOI: 10.1007/s11548-023-02936-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Accepted: 04/24/2023] [Indexed: 06/03/2023]
Abstract
PURPOSE Validation metrics are a key prerequisite for the reliable tracking of scientific progress and for deciding on the potential clinical translation of methods. While recent initiatives aim to develop comprehensive theoretical frameworks for understanding metric-related pitfalls in image analysis problems, there is a lack of experimental evidence on the concrete effects of common and rare pitfalls on specific applications. We address this gap in the literature in the context of colon cancer screening. METHODS Our contribution is twofold. Firstly, we present the winning solution of the Endoscopy Computer Vision Challenge on colon cancer detection, conducted in conjunction with the IEEE International Symposium on Biomedical Imaging 2022. Secondly, we demonstrate the sensitivity of commonly used metrics to a range of hyperparameters as well as the consequences of poor metric choices. RESULTS Based on comprehensive validation studies performed with patient data from six clinical centers, we found all commonly applied object detection metrics to be subject to high inter-center variability. Furthermore, our results clearly demonstrate that the adaptation of standard hyperparameters used in the computer vision community does not generally lead to the clinically most plausible results. Finally, we present localization criteria that correspond well to clinical relevance. CONCLUSION We conclude from our study that (1) performance results in polyp detection are highly sensitive to various design choices, (2) common metric configurations do not reflect the clinical need and rely on suboptimal hyperparameters and (3) comparison of performance across datasets can be largely misleading. Our work could be a first step towards reconsidering common validation strategies in deep learning-based colonoscopy and beyond.
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Affiliation(s)
- T N Tran
- Division of Intelligent Medical Systems, DKFZ, Heidelberg, Germany.
| | - T J Adler
- Division of Intelligent Medical Systems, DKFZ, Heidelberg, Germany
| | - A Yamlahi
- Division of Intelligent Medical Systems, DKFZ, Heidelberg, Germany
| | - E Christodoulou
- Division of Intelligent Medical Systems, DKFZ, Heidelberg, Germany
| | - P Godau
- Division of Intelligent Medical Systems, DKFZ, Heidelberg, Germany
- Faculty of Mathematics and Computer Science, University of Heidelberg, Heidelberg, Germany
| | - A Reinke
- Division of Intelligent Medical Systems, DKFZ, Heidelberg, Germany
| | - M D Tizabi
- Division of Intelligent Medical Systems, DKFZ, Heidelberg, Germany
| | - P Sauer
- Interdisciplinary Endoscopy Center (IEZ), University Hospital Heidelberg, Heidelberg, Germany
| | - T Persicke
- Department of Gastroenterology, Hepatology and Endocrinology, Robert-Bosch Hospital (RBK), Stuttgart, Germany
| | - J G Albert
- Department of Gastroenterology, Hepatology and Endocrinology, Robert-Bosch Hospital (RBK), Stuttgart, Germany
- Clinic for General Internal Medicine, Gastroenterology, Hepatology and Infectiology, Pneumology, Klinikum Stuttgart, Stuttgart, Germany
| | - L Maier-Hein
- Division of Intelligent Medical Systems, DKFZ, Heidelberg, Germany
- Faculty of Mathematics and Computer Science, University of Heidelberg, Heidelberg, Germany
- National Center for Tumor Diseases (NCT), NCT Heidelberg, a Partnership Between DKFZ and University Medical Center Heidelberg, Heidelberg, Germany
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3
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Munugula C, Hu J, Christodoulou E, Yellapantula V. Microenvironmental changes co-occur with mosaic somatic clonal expansions in normal skin and esophagus tissues. Front Oncol 2022; 12:1021940. [DOI: 10.3389/fonc.2022.1021940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 11/15/2022] [Indexed: 12/03/2022] Open
Abstract
The presence of somatic mutations, previously identified in cancers, are being increasingly recognized in normal tissues. While the role of microenvironment (ME) in tumor progression is well understood, the changes that occur in the microenvironment of normal tissues that harbor somatic mutations has not been systematically studied. Here, using normal RNA-Seq data accrued from 6544 samples across 27 tissue types from Genotype-Tissue Expression (GTEx) project, we studied the association of microenvironmental changes in the presence of somatic clonal expansions of previously implicated cancer genes. We focused our analysis on skin and esophagus since they have the highest number of samples and mutation burden together. We observed changes in microenvironmental cell-types previously implicated in tumor progression including endothelial cells, epithelial cells, pericytes, fibroblasts, chondrocytes, among others. The Epithelial-Mesenchymal-Transition (EMT) pathway is dysregulated in both skin and esophagus, along with increased hypoxia scores in samples with clonal expansions. These results suggest that microenvironmental changes play an important role in clonal expansions and potentially the initiating stages of cancer progression. Studying these changes may provide new avenues for early intervention of cancer, for targeted therapies, or enhance activities of conventional therapies.
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4
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Karantzelis N, Petropoulos M, De Marco V, Egan DA, Fish A, Christodoulou E, Will DW, Lewis JD, Perrakis A, Lygerou Z, Taraviras S. Small Molecule Inhibitor Targeting CDT1/Geminin Protein Complex Promotes DNA Damage and Cell Death in Cancer Cells. Front Pharmacol 2022; 13:860682. [PMID: 35548337 PMCID: PMC9083542 DOI: 10.3389/fphar.2022.860682] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Accepted: 03/30/2022] [Indexed: 01/18/2023] Open
Abstract
DNA replication initiation requires the loading of MCM2-7 complexes at the origins of replication during G1. Replication licensing renders chromatin competent for DNA replication and its tight regulation is essential to prevent aberrant DNA replication and genomic instability. CDT1 is a critical factor of licensing and its activity is controlled by redundant mechanisms, including Geminin, a protein inhibitor of CDT1. Aberrant CDT1 and Geminin expression have been shown to promote tumorigenesis in vivo and are also evident in multiple human tumors. In this study, we developed an in vitro AlphaScreen™ high-throughput screening (HTS) assay for the identification of small-molecule inhibitors targeting the CDT1/Geminin protein complex. Biochemical characterization of the most potent compound, AF615, provided evidence of specific, dose-dependent inhibition of Geminin binding to CDT1 both in-vitro and in cells. Moreover, compound AF615 induces DNA damage, inhibits DNA synthesis and reduces viability selectively in cancer cell lines, and this effect is CDT1-dependent. Taken together, our data suggest that AF615 may serve as a useful compound to elucidate the role of CDT1/Geminin protein complex in replication licensing and origin firing as well as a scaffold for further medicinal chemistry optimisation.
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Affiliation(s)
| | - Michalis Petropoulos
- Department of General Biology, Medical School, University of Patras, Patras, Greece
| | - Valeria De Marco
- Division of Biochemistry, Netherlands Cancer Institute, Amsterdam, Netherlands
| | - David A Egan
- Division of Biochemistry, Netherlands Cancer Institute, Amsterdam, Netherlands
| | - Alexander Fish
- Division of Biochemistry, Netherlands Cancer Institute, Amsterdam, Netherlands
| | | | - David W Will
- Chemical Biology Core Facility, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Joe D Lewis
- Chemical Biology Core Facility, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Anastassis Perrakis
- Division of Biochemistry, Netherlands Cancer Institute, Amsterdam, Netherlands
| | - Zoi Lygerou
- Department of General Biology, Medical School, University of Patras, Patras, Greece
| | - Stavros Taraviras
- Department of Physiology, Medical School, University of Patras, Patras, Greece
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5
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Chaves-Arquero B, Collins KM, Christodoulou E, Nicastro G, Martin SR, Ramos A. The distinct RNA-interaction modes of a small ZnF domain underlay TUT4(7) diverse action in miRNA regulation. RNA Biol 2021; 18:770-781. [PMID: 34719327 PMCID: PMC8782169 DOI: 10.1080/15476286.2021.1991169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
TUT4 and the closely related TUT7 are non-templated poly(U) polymerases required at different stages of development, and their mis-regulation or mutation has been linked to important cancer pathologies. While TUT4(7) interaction with its pre-miRNA targets has been characterized in detail, the molecular bases of the broader target recognition process are unclear. Here, we examine RNA binding by the ZnF domains of the protein. We show that TUT4(7) ZnF2 contains two distinct RNA binding surfaces that are used in the interaction with different RNA nucleobases in different targets, i.e that this small domain encodes diversity in TUT4(7) selectivity and molecular function. Interestingly and unlike other well-characterized CCHC ZnFs, ZnF2 is not physically coupled to the flanking ZnF3 and acts independently in miRNA recognition, while the remaining CCHC ZnF of TUT4(7), ZnF1, has lost its intrinsic RNA binding capability. Together, our data suggest that the ZnFs of TUT4(7) are independent units for RNA and, possibly, protein-protein interactions that underlay the protein's functional flexibility and are likely to play an important role in building its interaction network.
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Affiliation(s)
- Belén Chaves-Arquero
- Institute of Structural and Molecular Biology (ISMB) instead of (Ismb), University College London, London, UK
| | - Katherine M Collins
- Institute of Structural and Molecular Biology (ISMB) instead of (Ismb), University College London, London, UK
| | | | - Giuseppe Nicastro
- Macromolecular Structure Laboratory, The Francis Crick Institute, London, UK
| | - Stephen R Martin
- Structural Biology Science Technology Platform, The Francis Crick Institute, London, UK
| | - Andres Ramos
- Institute of Structural and Molecular Biology (ISMB) instead of (Ismb), University College London, London, UK
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6
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Rosa A, Pye VE, Graham C, Muir L, Seow J, Ng KW, Cook NJ, Rees-Spear C, Parker E, Dos Santos MS, Rosadas C, Susana A, Rhys H, Nans A, Masino L, Roustan C, Christodoulou E, Ulferts R, Wrobel AG, Short CE, Fertleman M, Sanders RW, Heaney J, Spyer M, Kjær S, Riddell A, Malim MH, Beale R, MacRae JI, Taylor GP, Nastouli E, van Gils MJ, Rosenthal PB, Pizzato M, McClure MO, Tedder RS, Kassiotis G, McCoy LE, Doores KJ, Cherepanov P. SARS-CoV-2 can recruit a heme metabolite to evade antibody immunity. Sci Adv 2021; 7:eabg7607. [PMID: 33888467 PMCID: PMC8163077 DOI: 10.1126/sciadv.abg7607] [Citation(s) in RCA: 55] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 04/02/2021] [Indexed: 05/11/2023]
Abstract
The coronaviral spike is the dominant viral antigen and the target of neutralizing antibodies. We show that SARS-CoV-2 spike binds biliverdin and bilirubin, the tetrapyrrole products of heme metabolism, with nanomolar affinity. Using cryo-electron microscopy and x-ray crystallography, we mapped the tetrapyrrole interaction pocket to a deep cleft on the spike N-terminal domain (NTD). At physiological concentrations, biliverdin significantly dampened the reactivity of SARS-CoV-2 spike with immune sera and inhibited a subset of neutralizing antibodies. Access to the tetrapyrrole-sensitive epitope is gated by a flexible loop on the distal face of the NTD. Accompanied by profound conformational changes in the NTD, antibody binding requires relocation of the gating loop, which folds into the cleft vacated by the metabolite. Our results indicate that SARS-CoV-2 spike NTD harbors a dominant epitope, access to which can be controlled by an allosteric mechanism that is regulated through recruitment of a metabolite.
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Affiliation(s)
- Annachiara Rosa
- Chromatin Structure and Mobile DNA Laboratory, The Francis Crick Institute, London, UK
| | - Valerie E Pye
- Chromatin Structure and Mobile DNA Laboratory, The Francis Crick Institute, London, UK
| | - Carl Graham
- Department of Infectious Diseases, School of Immunology and Microbial Sciences, King's College London, London, UK
| | - Luke Muir
- Institute of Immunity and Transplantation, Division of Infection and Immunity, University College London, London, UK
| | - Jeffrey Seow
- Department of Infectious Diseases, School of Immunology and Microbial Sciences, King's College London, London, UK
| | - Kevin W Ng
- Retroviral Immunology Laboratory, The Francis Crick Institute, London, UK
| | - Nicola J Cook
- Chromatin Structure and Mobile DNA Laboratory, The Francis Crick Institute, London, UK
| | - Chloe Rees-Spear
- Institute of Immunity and Transplantation, Division of Infection and Immunity, University College London, London, UK
| | - Eleanor Parker
- Department of Infectious Disease, St. Mary's Campus, Imperial College London, London, UK
| | | | - Carolina Rosadas
- Department of Infectious Disease, St. Mary's Campus, Imperial College London, London, UK
| | - Alberto Susana
- Department of Cellular, Computational and Integrative Biology, University of Trento, Trento, Italy
| | - Hefin Rhys
- Flow Cytometry Science and Technology Platform, The Francis Crick Institute, London, UK
| | - Andrea Nans
- Structural Biology Science Technology Platform, The Francis Crick Institute, London, UK
| | - Laura Masino
- Structural Biology Science Technology Platform, The Francis Crick Institute, London, UK
| | - Chloe Roustan
- Structural Biology Science Technology Platform, The Francis Crick Institute, London, UK
| | | | - Rachel Ulferts
- Cell Biology of Infection Laboratory, The Francis Crick Institute, London, UK
| | - Antoni G Wrobel
- Structural Biology of Disease Processes Laboratory, The Francis Crick Institute, London, UK
| | - Charlotte-Eve Short
- Department of Infectious Disease, St. Mary's Campus, Imperial College London, London, UK
| | - Michael Fertleman
- Cutrale Perioperative and Ageing Group, Imperial College London, London, UK
| | - Rogier W Sanders
- Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam Institute for Infection and Immunity, Amsterdam, Netherlands
- Weill Medical College of Cornell University, New York, NY, USA
| | - Judith Heaney
- Advanced Pathogen Diagnostic Unit, University College London Hospitals NHS Foundation Trust, London, UK
- Crick COVID-19 Consortium, The Francis Crick Institute, London, UK
| | - Moira Spyer
- Advanced Pathogen Diagnostic Unit, University College London Hospitals NHS Foundation Trust, London, UK
- Crick COVID-19 Consortium, The Francis Crick Institute, London, UK
- Department of Infection, Immunity and Inflammation, UCL Great Ormond Street Institute of Child Health
| | - Svend Kjær
- Structural Biology Science Technology Platform, The Francis Crick Institute, London, UK
| | - Andy Riddell
- Flow Cytometry Science and Technology Platform, The Francis Crick Institute, London, UK
| | - Michael H Malim
- Department of Infectious Diseases, School of Immunology and Microbial Sciences, King's College London, London, UK
| | - Rupert Beale
- Cell Biology of Infection Laboratory, The Francis Crick Institute, London, UK
| | - James I MacRae
- Metabolomics Science Technology Platform, The Francis Crick Institute, London, UK
| | - Graham P Taylor
- Department of Infectious Disease, St. Mary's Campus, Imperial College London, London, UK
| | - Eleni Nastouli
- Advanced Pathogen Diagnostic Unit, University College London Hospitals NHS Foundation Trust, London, UK
- Crick COVID-19 Consortium, The Francis Crick Institute, London, UK
- Department of Infection, Immunity and Inflammation, UCL Great Ormond Street Institute of Child Health
| | - Marit J van Gils
- Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam Institute for Infection and Immunity, Amsterdam, Netherlands
| | - Peter B Rosenthal
- Structural Biology of Cells and Viruses Laboratory, The Francis Crick Institute, London, UK
| | - Massimo Pizzato
- Department of Cellular, Computational and Integrative Biology, University of Trento, Trento, Italy
| | - Myra O McClure
- Department of Infectious Disease, St. Mary's Campus, Imperial College London, London, UK
| | - Richard S Tedder
- Department of Infectious Disease, St. Mary's Campus, Imperial College London, London, UK
| | - George Kassiotis
- Retroviral Immunology Laboratory, The Francis Crick Institute, London, UK.
- Department of Infectious Disease, St. Mary's Campus, Imperial College London, London, UK
| | - Laura E McCoy
- Institute of Immunity and Transplantation, Division of Infection and Immunity, University College London, London, UK.
| | - Katie J Doores
- Department of Infectious Diseases, School of Immunology and Microbial Sciences, King's College London, London, UK.
| | - Peter Cherepanov
- Chromatin Structure and Mobile DNA Laboratory, The Francis Crick Institute, London, UK.
- Department of Infectious Disease, St. Mary's Campus, Imperial College London, London, UK
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7
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Peleg Y, Vincentelli R, Collins BM, Chen KE, Livingstone EK, Weeratunga S, Leneva N, Guo Q, Remans K, Perez K, Bjerga GEK, Larsen Ø, Vaněk O, Skořepa O, Jacquemin S, Poterszman A, Kjær S, Christodoulou E, Albeck S, Dym O, Ainbinder E, Unger T, Schuetz A, Matthes S, Bader M, de Marco A, Storici P, Semrau MS, Stolt-Bergner P, Aigner C, Suppmann S, Goldenzweig A, Fleishman SJ. Community-Wide Experimental Evaluation of the PROSS Stability-Design Method. J Mol Biol 2021; 433:166964. [PMID: 33781758 DOI: 10.1016/j.jmb.2021.166964] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 03/08/2021] [Accepted: 03/22/2021] [Indexed: 10/21/2022]
Abstract
Recent years have seen a dramatic improvement in protein-design methodology. Nevertheless, most methods demand expert intervention, limiting their widespread adoption. By contrast, the PROSS algorithm for improving protein stability and heterologous expression levels has been successfully applied to a range of challenging enzymes and binding proteins. Here, we benchmark the application of PROSS as a stand-alone tool for protein scientists with no or limited experience in modeling. Twelve laboratories from the Protein Production and Purification Partnership in Europe (P4EU) challenged the PROSS algorithm with 14 unrelated protein targets without support from the PROSS developers. For each target, up to six designs were evaluated for expression levels and in some cases, for thermal stability and activity. In nine targets, designs exhibited increased heterologous expression levels either in prokaryotic and/or eukaryotic expression systems under experimental conditions that were tailored for each target protein. Furthermore, we observed increased thermal stability in nine of ten tested targets. In two prime examples, the human Stem Cell Factor (hSCF) and human Cadherin-Like Domain (CLD12) from the RET receptor, the wild type proteins were not expressible as soluble proteins in E. coli, yet the PROSS designs exhibited high expression levels in E. coli and HEK293 cells, respectively, and improved thermal stability. We conclude that PROSS may improve stability and expressibility in diverse cases, and that improvement typically requires target-specific expression conditions. This study demonstrates the strengths of community-wide efforts to probe the generality of new methods and recommends areas for future research to advance practically useful algorithms for protein science.
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Affiliation(s)
- Yoav Peleg
- Department of Life Sciences Core Facilities (LSCF), Weizmann Institute of Science, Rehovot 7610001, Israel.
| | - Renaud Vincentelli
- Unité Mixte de Recherche (UMR) 7257, Centre National de la Recherche Scientifique (CNRS) Aix-Marseille Université, Architecture et Fonction des Macromolécules Biologiques (AFMB), Marseille, France
| | - Brett M Collins
- The University of Queensland, Institute for Molecular Bioscience, St. Lucia, Queensland 4072, Australia
| | - Kai-En Chen
- The University of Queensland, Institute for Molecular Bioscience, St. Lucia, Queensland 4072, Australia
| | - Emma K Livingstone
- The University of Queensland, Institute for Molecular Bioscience, St. Lucia, Queensland 4072, Australia
| | - Saroja Weeratunga
- The University of Queensland, Institute for Molecular Bioscience, St. Lucia, Queensland 4072, Australia
| | - Natalya Leneva
- The University of Queensland, Institute for Molecular Bioscience, St. Lucia, Queensland 4072, Australia
| | - Qian Guo
- The University of Queensland, Institute for Molecular Bioscience, St. Lucia, Queensland 4072, Australia
| | - Kim Remans
- European Molecular Biology Laboratory (EMBL), Protein Expression and Purification Core Facility, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Kathryn Perez
- European Molecular Biology Laboratory (EMBL), Protein Expression and Purification Core Facility, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Gro E K Bjerga
- NORCE Norwegian Research Centre, Postboks 22 Nygårdstangen, 5038 Bergen, Norway
| | - Øivind Larsen
- NORCE Norwegian Research Centre, Postboks 22 Nygårdstangen, 5038 Bergen, Norway
| | - Ondřej Vaněk
- Department of Biochemistry, Faculty of Science, Charles University, Hlavova 2030/8, 12840 Prague, Czech Republic
| | - Ondřej Skořepa
- Department of Biochemistry, Faculty of Science, Charles University, Hlavova 2030/8, 12840 Prague, Czech Republic
| | - Sophie Jacquemin
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Centre National de la Recherche Scientifique (CNRS), UMR 7104, Institut National de la Santé et de la Recherche Médicale (INSERM), U1258, Université de Strasbourg, France
| | - Arnaud Poterszman
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Centre National de la Recherche Scientifique (CNRS), UMR 7104, Institut National de la Santé et de la Recherche Médicale (INSERM), U1258, Université de Strasbourg, France
| | - Svend Kjær
- Structural Biology Science Technology Platform, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Evangelos Christodoulou
- Structural Biology Science Technology Platform, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Shira Albeck
- Department of Life Sciences Core Facilities (LSCF), Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Orly Dym
- Department of Life Sciences Core Facilities (LSCF), Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Elena Ainbinder
- Department of Life Sciences Core Facilities (LSCF), Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Tamar Unger
- Department of Life Sciences Core Facilities (LSCF), Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Anja Schuetz
- Max-Delbrück Center for Molecular Medicine (MDC), Robert-Rössle-Straße 10, 13125 Berlin-Buch, Germany
| | - Susann Matthes
- Max-Delbrück Center for Molecular Medicine (MDC), Robert-Rössle-Straße 10, 13125 Berlin-Buch, Germany
| | - Michael Bader
- Max-Delbrück Center for Molecular Medicine (MDC), Robert-Rössle-Straße 10, 13125 Berlin-Buch, Germany; University of Lübeck, Institute for Biology, Ratzeburger Allee 160, 23562 Lübeck, Germany; Charité University Medicine, Charitéplatz 1, 10117 Berlin, Germany; German Center for Cardiovascular Research (DZHK), Partner Site Berlin, Berlin, Germany
| | - Ario de Marco
- Laboratory for Environmental and Life Sciences, University of Nova Gorica, Slovenia
| | - Paola Storici
- Elettra Sincrotrone Trieste - SS 14 - km 163, 5 in Area Science Park, 34149 Basovizza, Trieste, Italy
| | - Marta S Semrau
- Elettra Sincrotrone Trieste - SS 14 - km 163, 5 in Area Science Park, 34149 Basovizza, Trieste, Italy
| | - Peggy Stolt-Bergner
- Vienna Biocenter Core Facilities GmbH, Dr. Bohr-gasse 3, 1030 Vienna, Austria
| | - Christian Aigner
- Vienna Biocenter Core Facilities GmbH, Dr. Bohr-gasse 3, 1030 Vienna, Austria
| | - Sabine Suppmann
- Max-Planck Institute of Biochemistry, Biochemistry Core Facility, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - Adi Goldenzweig
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Sarel J Fleishman
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel.
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8
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Rosa A, Pye VE, Graham C, Muir L, Seow J, Ng KW, Cook NJ, Rees-Spear C, Parker E, dos Santos MS, Rosadas C, Susana A, Rhys H, Nans A, Masino L, Roustan C, Christodoulou E, Ulferts R, Wrobel A, Short CE, Fertleman M, Sanders RW, Heaney J, Spyer M, Kjær S, Riddell A, Malim MH, Beale R, MacRae JI, Taylor GP, Nastouli E, van Gils MJ, Rosenthal PB, Pizzato M, McClure MO, Tedder RS, Kassiotis G, McCoy LE, Doores KJ, Cherepanov P. SARS-CoV-2 recruits a haem metabolite to evade antibody immunity. medRxiv 2021:2021.01.21.21249203. [PMID: 33532784 PMCID: PMC7852234 DOI: 10.1101/2021.01.21.21249203] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The coronaviral spike is the dominant viral antigen and the target of neutralizing antibodies. We show that SARS-CoV-2 spike binds biliverdin and bilirubin, the tetrapyrrole products of haem metabolism, with nanomolar affinity. Using cryo-electron microscopy and X-ray crystallography we mapped the tetrapyrrole interaction pocket to a deep cleft on the spike N-terminal domain (NTD). At physiological concentrations, biliverdin significantly dampened the reactivity of SARS-CoV-2 spike with immune sera and inhibited a subset of neutralizing antibodies. Access to the tetrapyrrole-sensitive epitope is gated by a flexible loop on the distal face of the NTD. Accompanied by profound conformational changes in the NTD, antibody binding requires relocation of the gating loop, which folds into the cleft vacated by the metabolite. Our results indicate that the virus co-opts the haem metabolite for the evasion of humoral immunity via allosteric shielding of a sensitive epitope and demonstrate the remarkable structural plasticity of the NTD.
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Affiliation(s)
- Annachiara Rosa
- Chromatin Structure and Mobile DNA Laboratory, The Francis Crick Institute, London, UK
| | - Valerie E. Pye
- Chromatin Structure and Mobile DNA Laboratory, The Francis Crick Institute, London, UK
| | - Carl Graham
- Department of Infectious Diseases, School of Immunology & Microbial Sciences, King’s College London, UK
| | - Luke Muir
- Institute of Immunity and Transplantation, Division of Infection and Immunity, University College London, London, UK
| | - Jeffrey Seow
- Department of Infectious Diseases, School of Immunology & Microbial Sciences, King’s College London, UK
| | - Kevin W. Ng
- Retroviral Immunology Laboratory, The Francis Crick Institute, London, UK
| | - Nicola J. Cook
- Chromatin Structure and Mobile DNA Laboratory, The Francis Crick Institute, London, UK
| | - Chloe Rees-Spear
- Institute of Immunity and Transplantation, Division of Infection and Immunity, University College London, London, UK
| | - Eleanor Parker
- Department of Infectious Disease, St-Mary’s Campus, Imperial College London, UK
| | | | - Carolina Rosadas
- Department of Infectious Disease, St-Mary’s Campus, Imperial College London, UK
| | - Alberto Susana
- Department of Cellular, Computational and Integrative Biology, University of Trento, Italy
| | - Hefin Rhys
- Flow Cytometry Science and Technology Platform, The Francis Crick Institute, London, UK
| | - Andrea Nans
- Structural Biology Science Technology Platform, The Francis Crick Institute, London, UK
| | - Laura Masino
- Structural Biology Science Technology Platform, The Francis Crick Institute, London, UK
| | - Chloe Roustan
- Structural Biology Science Technology Platform, The Francis Crick Institute, London, UK
| | | | - Rachel Ulferts
- Cell Biology of Infection Laboratory, The Francis Crick Institute, London, UK
| | - Antoni Wrobel
- Structural Biology of Disease Processes Laboratory, The Francis Crick Institute, London, UK
| | - Charlotte-Eve Short
- Department of Infectious Disease, St-Mary’s Campus, Imperial College London, UK
| | | | - Rogier W. Sanders
- Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam Institute for Infection and Immunity, Amsterdam, Netherlands
- Weill Medical College of Cornell University, New York, US
| | - Judith Heaney
- Advanced Pathogen Diagnostic Unit, University College London Hospitals NHS Foundation Trust, London, UK
- Crick COVID-19 Consortium, The Francis Crick Institute, London, UK
| | - Moira Spyer
- Advanced Pathogen Diagnostic Unit, University College London Hospitals NHS Foundation Trust, London, UK
- Crick COVID-19 Consortium, The Francis Crick Institute, London, UK
- Department of Infection, Immunity and Inflammation, UCL Great Ormond Street Institute of Child Health
| | - Svend Kjær
- Structural Biology Science Technology Platform, The Francis Crick Institute, London, UK
| | - Andy Riddell
- Flow Cytometry Science and Technology Platform, The Francis Crick Institute, London, UK
| | - Michael H. Malim
- Department of Infectious Diseases, School of Immunology & Microbial Sciences, King’s College London, UK
| | - Rupert Beale
- Cell Biology of Infection Laboratory, The Francis Crick Institute, London, UK
| | - James I. MacRae
- Metabolomics Science Technology Platform, The Francis Crick Institute, London, UK
| | - Graham P. Taylor
- Department of Infectious Disease, St-Mary’s Campus, Imperial College London, UK
| | - Eleni Nastouli
- Advanced Pathogen Diagnostic Unit, University College London Hospitals NHS Foundation Trust, London, UK
- Crick COVID-19 Consortium, The Francis Crick Institute, London, UK
- Department of Infection, Immunity and Inflammation, UCL Great Ormond Street Institute of Child Health
| | - Marit J. van Gils
- Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam Institute for Infection and Immunity, Amsterdam, Netherlands
| | - Peter B. Rosenthal
- Structural Biology of Cells and Viruses Laboratory, The Francis Crick Institute, London, UK
| | - Massimo Pizzato
- Department of Cellular, Computational and Integrative Biology, University of Trento, Italy
| | - Myra O. McClure
- Department of Infectious Disease, St-Mary’s Campus, Imperial College London, UK
| | - Richard S. Tedder
- Department of Infectious Disease, St-Mary’s Campus, Imperial College London, UK
| | - George Kassiotis
- Retroviral Immunology Laboratory, The Francis Crick Institute, London, UK
- Department of Infectious Disease, St-Mary’s Campus, Imperial College London, UK
| | - Laura E. McCoy
- Institute of Immunity and Transplantation, Division of Infection and Immunity, University College London, London, UK
| | - Katie J. Doores
- Department of Infectious Diseases, School of Immunology & Microbial Sciences, King’s College London, UK
| | - Peter Cherepanov
- Chromatin Structure and Mobile DNA Laboratory, The Francis Crick Institute, London, UK
- Department of Infectious Disease, St-Mary’s Campus, Imperial College London, UK
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9
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Christodoulou E, Bobdiwala S, Kyriacou C, Farren J, Mitchell-Jones N, Ayim F, Chohan B, Abughazza O, Guruwadahyarhalli B, Al-Memar M, Guha S, Vathanan V, Gould D, Stalder C, Wynants L, Timmerman D, Bourne T, Van Calster B. External validation of models to predict the outcome of pregnancies of unknown location: a multicentre cohort study. BJOG 2020; 128:552-562. [PMID: 32931087 PMCID: PMC7821217 DOI: 10.1111/1471-0528.16497] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/28/2020] [Indexed: 12/23/2022]
Abstract
Objective To validate externally five approaches to predict ectopic pregnancy (EP) in pregnancies of unknown location (PUL): the M6P and M6NP risk models, the two‐step triage strategy (2ST, which incorporates M6P), the M4 risk model, and beta human chorionic gonadotropin ratio cut‐offs (BhCG‐RC). Design Secondary analysis of a prospective cohort study. Setting Eight UK early pregnancy assessment units. Population Women presenting with a PUL and BhCG >25 IU/l. Methods Women were managed using the 2ST protocol: PUL were classified as low risk of EP if presenting progesterone ≤2 nmol/l; the remaining cases returned 2 days later for triage based on M6P. EP risk ≥5% was used to classify PUL as high risk. Missing values were imputed, and predictions for the five approaches were calculated post hoc. We meta‐analysed centre‐specific results. Main outcome measures Discrimination, calibration and clinical utility (decision curve analysis) for predicting EP. Results Of 2899 eligible women, the primary analysis excluded 297 (10%) women who were lost to follow up. The area under the ROC curve for EP was 0.89 (95% CI 0.86–0.91) for M6P, 0.88 (0.86–0.90) for 2ST, 0.86 (0.83–0.88) for M6NP and 0.82 (0.78–0.85) for M4. Sensitivities for EP were 96% (M6P), 94% (2ST), 92% (N6NP), 80% (M4) and 58% (BhCG‐RC); false‐positive rates were 35%, 33%, 39%, 24% and 13%. M6P and 2ST had the best clinical utility and good overall calibration, with modest variability between centres. Conclusions 2ST and M6P performed best for prediction and triage in PUL. Tweetable abstract The M6 model, as part of a two‐step triage strategy, is the best approach to characterise and triage PULs. The M6 model, as part of a two‐step triage strategy, is the best approach to characterise and triage PULs.
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Affiliation(s)
- E Christodoulou
- Department of Development and Regeneration, KU Leuven, Leuven, Belgium
| | - S Bobdiwala
- Tommy's National Centre for Miscarriage Research, Queen Charlotte's & Chelsea Hospital, Imperial College, London, UK
| | - C Kyriacou
- Tommy's National Centre for Miscarriage Research, Queen Charlotte's & Chelsea Hospital, Imperial College, London, UK
| | | | | | - F Ayim
- Hillingdon Hospital, London, UK
| | - B Chohan
- Wexham Park Hospital, Slough, UK
| | | | | | - M Al-Memar
- Tommy's National Centre for Miscarriage Research, Queen Charlotte's & Chelsea Hospital, Imperial College, London, UK
| | - S Guha
- Chelsea and Westminster NHS Trust, London, UK
| | | | - D Gould
- St Marys' Hospital, London, UK
| | - C Stalder
- Tommy's National Centre for Miscarriage Research, Queen Charlotte's & Chelsea Hospital, Imperial College, London, UK
| | - L Wynants
- Department of Development and Regeneration, KU Leuven, Leuven, Belgium.,Department of Epidemiology, CAPHRI Care and Public Health Research Institute, Maastricht University, Maastricht, The Netherlands
| | - D Timmerman
- Department of Development and Regeneration, KU Leuven, Leuven, Belgium.,Department of Obstetrics and Gynaecology, University Hospitals Leuven, Leuven, Belgium
| | - T Bourne
- Department of Development and Regeneration, KU Leuven, Leuven, Belgium.,Tommy's National Centre for Miscarriage Research, Queen Charlotte's & Chelsea Hospital, Imperial College, London, UK.,Department of Obstetrics and Gynaecology, University Hospitals Leuven, Leuven, Belgium
| | - B Van Calster
- Department of Development and Regeneration, KU Leuven, Leuven, Belgium.,Department of Biomedical Data Sciences, Leiden University Medical Centre, Leiden, The Netherlands.,EPI-Centre, KU Leuven, Leuven, Belgium
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10
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Green JL, Wu Y, Encheva V, Lasonder E, Prommaban A, Kunzelmann S, Christodoulou E, Grainger M, Truongvan N, Bothe S, Sharma V, Song W, Pinzuti I, Uthaipibull C, Srichairatanakool S, Birault V, Langsley G, Schindelin H, Stieglitz B, Snijders AP, Holder AA. Ubiquitin activation is essential for schizont maturation in Plasmodium falciparum blood-stage development. PLoS Pathog 2020; 16:e1008640. [PMID: 32569299 PMCID: PMC7332102 DOI: 10.1371/journal.ppat.1008640] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 07/02/2020] [Accepted: 05/17/2020] [Indexed: 11/19/2022] Open
Abstract
Ubiquitylation is a common post translational modification of eukaryotic proteins and in the human malaria parasite, Plasmodium falciparum (Pf) overall ubiquitylation increases in the transition from intracellular schizont to extracellular merozoite stages in the asexual blood stage cycle. Here, we identify specific ubiquitylation sites of protein substrates in three intraerythrocytic parasite stages and extracellular merozoites; a total of 1464 sites in 546 proteins were identified (data available via ProteomeXchange with identifier PXD014998). 469 ubiquitylated proteins were identified in merozoites compared with only 160 in the preceding intracellular schizont stage, suggesting a large increase in protein ubiquitylation associated with merozoite maturation. Following merozoite invasion of erythrocytes, few ubiquitylated proteins were detected in the first intracellular ring stage but as parasites matured through trophozoite to schizont stages the apparent extent of ubiquitylation increased. We identified commonly used ubiquitylation motifs and groups of ubiquitylated proteins in specific areas of cellular function, for example merozoite pellicle proteins involved in erythrocyte invasion, exported proteins, and histones. To investigate the importance of ubiquitylation we screened ubiquitin pathway inhibitors in a parasite growth assay and identified the ubiquitin activating enzyme (UBA1 or E1) inhibitor MLN7243 (TAK-243) to be particularly effective. This small molecule was shown to be a potent inhibitor of recombinant PfUBA1, and a structural homology model of MLN7243 bound to the parasite enzyme highlights avenues for the development of P. falciparum specific inhibitors. We created a genetically modified parasite with a rapamycin-inducible functional deletion of uba1; addition of either MLN7243 or rapamycin to the recombinant parasite line resulted in the same phenotype, with parasite development blocked at the schizont stage. Nuclear division and formation of intracellular structures was interrupted. These results indicate that the intracellular target of MLN7243 is UBA1, and this activity is essential for the final differentiation of schizonts to merozoites.
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Affiliation(s)
- Judith L. Green
- Malaria Parasitology Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Yang Wu
- Malaria Parasitology Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Vesela Encheva
- Mass Spectrometry Proteomics, The Francis Crick Institute, London, United Kingdom
| | - Edwin Lasonder
- School of Biomedical Science, University of Plymouth, Plymouth, United Kingdom
| | - Adchara Prommaban
- Malaria Parasitology Laboratory, The Francis Crick Institute, London, United Kingdom
- Department of Biochemistry, Chiang Mai University, Chiang Mai, Thailand
| | - Simone Kunzelmann
- Structural Biology Science Technology Platform, The Francis Crick Institute, London, United Kingdom
| | - Evangelos Christodoulou
- Structural Biology Science Technology Platform, The Francis Crick Institute, London, United Kingdom
| | - Munira Grainger
- Malaria Parasitology Laboratory, The Francis Crick Institute, London, United Kingdom
| | - Ngoc Truongvan
- Rudolf Virchow Center for Experimental Biomedicine, Universität Würzburg, Würzburg, Germany
| | - Sebastian Bothe
- Department of Chemistry and Pharmacy, University of Würzburg, Würzburg, Germany
| | - Vikram Sharma
- School of Biomedical Science, University of Plymouth, Plymouth, United Kingdom
| | - Wei Song
- School of Biological and Chemical Sciences, Queen Mary University of London, London, United Kingdom
| | - Irene Pinzuti
- School of Biological and Chemical Sciences, Queen Mary University of London, London, United Kingdom
| | - Chairat Uthaipibull
- National Center for Genetic Engineering and Biotechnology, Khlong Luang, Thailand
| | | | | | - Gordon Langsley
- Laboratoire de Biologie Cellulaire Comparative des Apicomplexes, Institut Cochin, Université Paris Descartes, Paris, France
| | - Hermann Schindelin
- Rudolf Virchow Center for Experimental Biomedicine, Universität Würzburg, Würzburg, Germany
| | - Benjamin Stieglitz
- School of Biological and Chemical Sciences, Queen Mary University of London, London, United Kingdom
| | | | - Anthony A. Holder
- Malaria Parasitology Laboratory, The Francis Crick Institute, London, United Kingdom
- * E-mail:
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11
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Dobrovolska O, Brilkov M, Madeleine N, Ødegård-Fougner Ø, Strømland Ø, Martin SR, De Marco V, Christodoulou E, Teigen K, Isaksson J, Underhaug J, Reuter N, Aalen RB, Aasland R, Halskau Ø. The Arabidopsis (ASHH2) CW domain binds monomethylated K4 of the histone H3 tail through conformational selection. FEBS J 2020; 287:4458-4480. [PMID: 32083791 DOI: 10.1111/febs.15256] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 12/17/2019] [Accepted: 02/20/2020] [Indexed: 12/27/2022]
Abstract
Chromatin post-translational modifications are thought to be important for epigenetic effects on gene expression. Methylation of histone N-terminal tail lysine residues constitutes one of many such modifications, executed by families of histone lysine methyltransferase (HKMTase). One such protein is ASHH2 from the flowering plant Arabidopsis thaliana, equipped with the interaction domain, CW, and the HKMTase domain, SET. The CW domain of ASHH2 is a selective binder of monomethylation at lysine 4 on histone H3 (H3K4me1) and likely helps the enzyme dock correctly onto chromatin sites. The study of CW and related interaction domains has so far been emphasizing lock-key models, missing important aspects of histone-tail CW interactions. We here present an analysis of the ASHH2 CW-H3K4me1 complex using NMR and molecular dynamics, as well as mutation and affinity studies of flexible coils. β-augmentation and rearrangement of coils coincide with changes in the flexibility of the complex, in particular the η1, η3 and C-terminal coils, but also in the β1 and β2 strands and the C-terminal part of the ligand. Furthermore, we show that mutating residues with outlier dynamic behaviour affect the complex binding affinity despite these not being in direct contact with the ligand. Overall, the binding process is consistent with conformational selection. We propose that this binding mechanism presents an advantage when searching for the correct post-translational modification state among the highly modified and flexible histone tails, and also that the binding shifts the catalytic SET domain towards the nucleosome. DATABASES: Structural data are available in the PDB database under the accession code 6QXZ. Resonance assignments for CW42 in its apo- and holo-forms are available in the BMRB database under the accession code 27251.
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Affiliation(s)
- Olena Dobrovolska
- Department of Biological Sciences, University of Bergen, Norway, Bergen
| | - Maxim Brilkov
- Department of Biological Sciences, University of Bergen, Norway, Bergen
| | - Noelly Madeleine
- Department of Biological Sciences, University of Bergen, Norway, Bergen.,Department of Biomedicine, University of Bergen, Norway, Bergen
| | - Øyvind Ødegård-Fougner
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | | | - Stephen R Martin
- Structural Biology Science Technology Platform, Francis Crick Institute, London, UK
| | | | | | - Knut Teigen
- Department of Biomedicine, University of Bergen, Norway, Bergen
| | - Johan Isaksson
- Department of Chemistry, The Arctic University of Tromsø, Norway
| | - Jarl Underhaug
- Department of Chemistry, University of Bergen, Norway, Bergen
| | - Nathalie Reuter
- Department of Chemistry, University of Bergen, Norway, Bergen
| | | | - Rein Aasland
- Department of Biosciences, University of Oslo, Norway, Oslo
| | - Øyvind Halskau
- Department of Biological Sciences, University of Bergen, Norway, Bergen
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12
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Bobdiwala S, Christodoulou E, Farren J, Mitchell-Jones N, Kyriacou C, Al-Memar M, Ayim F, Chohan B, Kirk E, Abughazza O, Guruwadahyarhalli B, Guha S, Vathanan V, Bottomley C, Gould D, Stalder C, Timmerman D, van Calster B, Bourne T. Triaging women with pregnancy of unknown location using two-step protocol including M6 model: clinical implementation study. Ultrasound Obstet Gynecol 2020; 55:105-114. [PMID: 31385381 DOI: 10.1002/uog.20420] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Revised: 07/19/2019] [Accepted: 07/26/2019] [Indexed: 06/10/2023]
Abstract
OBJECTIVE The M6 risk-prediction model was published as part of a two-step protocol using an initial progesterone level of ≤ 2 nmol/L to identify probable failing pregnancies (Step 1) followed by the M6 model (Step 2). The M6 model has been shown to have good triage performance for stratifying women with a pregnancy of unknown location (PUL) as being at low or high risk of harboring an ectopic pregnancy (EP). This study validated the triage performance of the two-step protocol in clinical practice by evaluating the number of protocol-related adverse events and how effectively patients were triaged. METHODS This was a prospective multicenter interventional study of 3272 women with a PUL, carried out between January 2015 and January 2017 in four district general hospitals and four university teaching hospitals in the UK. The final pregnancy outcome was defined as: a failed PUL (FPUL), an intrauterine pregnancy (IUP) or an EP (including persistent PUL (PPUL)). FPUL and IUP were grouped as low-risk and EP/PPUL as high-risk PUL. Serum progesterone and human chorionic gonadotropin (hCG) levels were measured at presentation in all patients. If the initial progesterone level was ≤ 2 nmol/L, patients were discharged and were asked to have a follow-up urine pregnancy test in 2 weeks to confirm a negative result. If the progesterone level was > 2 nmol/L or a measurement had not been taken, hCG level was measured again at 48 h and results were entered into the M6 model. Patients were managed according to the outcome predicted by the protocol. Those classified as 'low risk, probable FPUL' were advised to perform a urine pregnancy test in 2 weeks and those classified as 'low risk, probable IUP' were invited for a scan a week later. When a woman with a PUL was classified as high risk (i.e. risk of EP ≥ 5%) she was reviewed clinically within 48 h. One center used a progesterone cut-off of ≤ 10 nmol/L and its data were analyzed separately. If the recommended management protocol was not adhered to, this was recorded as a protocol deviation and classified as: unscheduled visit for clinician reason, unscheduled visit for patient reason or incorrect timing of blood test or ultrasound scan. The classifications outlined in the UK Good Clinical Practice (GCP) guidelines were used to evaluate the incidence of adverse events. Data were analyzed using descriptive statistics. RESULTS Of the 3272 women with a PUL, 2625 were included in the final analysis (317 met the exclusion criteria or were lost to follow-up, while 330 were evaluated using a progesterone cut-off of ≤ 10 nmol/L). Initial progesterone results were available for 2392 (91.1%) patients. In Step 1, 407 (15.5%) patients were classified as low risk (progesterone ≤ 2 nmol/L), of whom seven (1.7%) were ultimately diagnosed with an EP. In 279 of the remaining 2218 women with a PUL, the M6 model was not applied owing to protocol deviation or because the outcome was already known (usually on the basis of an ultrasound scan) before a second hCG reading was taken; of these patients, 30 were diagnosed with an EP. In Step 2, 1038 women with a PUL were classified as low risk, of whom eight (0.8%) had a final outcome of EP. Of 901 women classified as high risk at Step 2, 275 (30.5%) had an EP. Therefore, 275/320 (85.9%) EPs were correctly classified as high risk. Overall, 1445/2625 PUL (55.0%) were classified as low risk, of which 15 (1.0%) were EP. None of these cases resulted in a ruptured EP or significant clinical harm. Sixty-two women participating in the study had an adverse event, but no woman had a serious adverse event as defined in the UK GCP guidelines. CONCLUSIONS This study has shown that the two-step protocol incorporating the M6 model effectively triaged the majority of women with a PUL as being at low risk of an EP, minimizing the follow-up required for these patients after just two visits. There were few misclassified EPs and none of these women came to significant clinical harm or suffered a serious adverse clinical event. The two-step protocol incorporating the M6 model is an effective and clinically safe way of rationalizing the management of women with a PUL. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.
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Affiliation(s)
- S Bobdiwala
- Tommy's National Centre for Miscarriage Research, Queen Charlotte's & Chelsea Hospital, Imperial College London, London, UK
| | - E Christodoulou
- KU Leuven, Department of Development & Regeneration, Leuven, Belgium
| | | | | | - C Kyriacou
- Tommy's National Centre for Miscarriage Research, Queen Charlotte's & Chelsea Hospital, Imperial College London, London, UK
| | - M Al-Memar
- Tommy's National Centre for Miscarriage Research, Queen Charlotte's & Chelsea Hospital, Imperial College London, London, UK
| | - F Ayim
- Hillingdon Hospital, London, UK
| | - B Chohan
- Wexham Park Hospital, Slough, UK
| | - E Kirk
- Royal Free NHS Foundation Trust, London, UK
| | | | | | - S Guha
- Chelsea and Westminster NHS Foundation Trust, London, UK
| | | | - C Bottomley
- Chelsea and Westminster NHS Foundation Trust, London, UK
| | - D Gould
- St Marys' Hospital, London, UK
| | - C Stalder
- Tommy's National Centre for Miscarriage Research, Queen Charlotte's & Chelsea Hospital, Imperial College London, London, UK
| | - D Timmerman
- KU Leuven, Department of Development & Regeneration, Leuven, Belgium
- University Hospital Leuven, Leuven, Belgium
| | - B van Calster
- KU Leuven, Department of Development & Regeneration, Leuven, Belgium
- Leiden University Medical Centre, Leiden, The Netherlands
| | - T Bourne
- Tommy's National Centre for Miscarriage Research, Queen Charlotte's & Chelsea Hospital, Imperial College London, London, UK
- KU Leuven, Department of Development & Regeneration, Leuven, Belgium
- University Hospital Leuven, Leuven, Belgium
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13
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Christodoulou E, Visser M, Potjer TP, van der Stoep N, Rodríguez-Girondo M, van Doorn R, Gruis N. Assessing a single SNP located at TERT/CLPTM1L multi-cancer risk region as a genetic modifier for risk of pancreatic cancer and melanoma in Dutch CDKN2A mutation carriers. Fam Cancer 2019; 18:439-444. [PMID: 31203567 PMCID: PMC6784815 DOI: 10.1007/s10689-019-00137-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Carriers of pathogenic variants in CDKN2A have a 70% life-time risk of developing melanoma and 15–20% risk of developing pancreatic cancer (PC). In the Netherlands, a 19-bp deletion in exon 2 of CDKN2A (p16-Leiden mutation) accounts for most hereditary melanoma cases. Clinical experience suggests variability in occurrence of melanoma and PC in p16-Leiden families. Thereby, the risk of developing cancer could be modified by both environmental and genetic contributors, suggesting that identification of genetic modifiers could improve patients’ surveillance. In a recent genome-wide association study (GWAS), rs36115365-C was found to significantly modify risk of PC and melanoma in the European population. This SNP is located on chr5p15.33 and has allele-specific regulatory activities on TERT expression. Herein, we investigated the modifying capacities of rs36115365-C on PC and melanoma in a cohort of 283 p16-Leiden carriers including 29 diagnosed with PC, 171 diagnosed with melanoma, 21 diagnosed with both PC and melanoma and 62 with neither PC nor melanoma. In contrast to previously reported findings, we did not find a significant association of PC risk with risk variant presence as determined by Generalized Estimating Equations (GEE) modelling. Interestingly, carrier-ship of the risk variant had a significant protective effect for melanoma (OR − 0.703 [95% CI − 1.201 to − 0.205], p = 0.006); however, the observed association was no longer significant after exclusion of probands to assess possible influence of ascertainment. Collectively, genetic modifiers for the prediction of PC and melanoma risk in p16-Leiden carriers remain to be determined.
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Affiliation(s)
- E Christodoulou
- Department of Dermatology, Leiden University Medical Center (LUMC), Albinusdreef 2, 2333 ZA, Leiden, The Netherlands.
| | - M Visser
- Department of Dermatology, Leiden University Medical Center (LUMC), Albinusdreef 2, 2333 ZA, Leiden, The Netherlands
| | - T P Potjer
- Department of Clinical Genetics, LUMC, Albinusdreef 2, 2333 ZA, Leiden, The Netherlands
| | - N van der Stoep
- Department of Clinical Genetics, LUMC, Albinusdreef 2, 2333 ZA, Leiden, The Netherlands
| | - M Rodríguez-Girondo
- Section of Medical Statistics, Department of Biomedical Data Sciences, LUMC, Einthovenweg 20, 2333 ZC, Leiden, The Netherlands
| | - R van Doorn
- Department of Dermatology, Leiden University Medical Center (LUMC), Albinusdreef 2, 2333 ZA, Leiden, The Netherlands
| | - N Gruis
- Department of Dermatology, Leiden University Medical Center (LUMC), Albinusdreef 2, 2333 ZA, Leiden, The Netherlands
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14
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Baltussen LL, Negraes PD, Silvestre M, Claxton S, Moeskops M, Christodoulou E, Flynn HR, Snijders AP, Muotri AR, Ultanir SK. Chemical genetic identification of CDKL5 substrates reveals its role in neuronal microtubule dynamics. EMBO J 2018; 37:embj.201899763. [PMID: 30266824 PMCID: PMC6293278 DOI: 10.15252/embj.201899763] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 08/07/2018] [Accepted: 08/31/2018] [Indexed: 01/23/2023] Open
Abstract
Loss‐of‐function mutations in CDKL5 kinase cause severe neurodevelopmental delay and early‐onset seizures. Identification of CDKL5 substrates is key to understanding its function. Using chemical genetics, we found that CDKL5 phosphorylates three microtubule‐associated proteins: MAP1S, EB2 and ARHGEF2, and determined the phosphorylation sites. Substrate phosphorylations are greatly reduced in CDKL5 knockout mice, verifying these as physiological substrates. In CDKL5 knockout mouse neurons, dendritic microtubules have longer EB3‐labelled plus‐end growth duration and these altered dynamics are rescued by reduction of MAP1S levels through shRNA expression, indicating that CDKL5 regulates microtubule dynamics via phosphorylation of MAP1S. We show that phosphorylation by CDKL5 is required for MAP1S dissociation from microtubules. Additionally, anterograde cargo trafficking is compromised in CDKL5 knockout mouse dendrites. Finally, EB2 phosphorylation is reduced in patient‐derived human neurons. Our results reveal a novel activity‐dependent molecular pathway in dendritic microtubule regulation and suggest a pathological mechanism which may contribute to CDKL5 deficiency disorder.
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Affiliation(s)
- Lucas L Baltussen
- Kinases and Brain Development Laboratory, The Francis Crick Institute, London, UK
| | - Priscilla D Negraes
- Department of Pediatrics, School of Medicine, University of California San Diego, La Jolla, CA, USA
| | - Margaux Silvestre
- Kinases and Brain Development Laboratory, The Francis Crick Institute, London, UK
| | - Suzanne Claxton
- Kinases and Brain Development Laboratory, The Francis Crick Institute, London, UK
| | - Max Moeskops
- Kinases and Brain Development Laboratory, The Francis Crick Institute, London, UK
| | | | - Helen R Flynn
- Proteomics Science Technology Platform, The Francis Crick Institute, London, UK
| | | | - Alysson R Muotri
- Department of Pediatrics, School of Medicine, University of California San Diego, La Jolla, CA, USA .,Department of Pediatrics/Cellular & Molecular Medicine, Center for Academic Research and Training in Anthropogeny (CARTA), Kavli Institute for Brain and Mind, School of Medicine, Rady Children's Hospital San Diego, University of California San Diego, La Jolla, CA, USA
| | - Sila K Ultanir
- Kinases and Brain Development Laboratory, The Francis Crick Institute, London, UK
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15
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Hobor F, Dallmann A, Ball NJ, Cicchini C, Battistelli C, Ogrodowicz RW, Christodoulou E, Martin SR, Castello A, Tripodi M, Taylor IA, Ramos A. A cryptic RNA-binding domain mediates Syncrip recognition and exosomal partitioning of miRNA targets. Nat Commun 2018; 9:831. [PMID: 29483512 PMCID: PMC5827114 DOI: 10.1038/s41467-018-03182-3] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 01/25/2018] [Indexed: 01/18/2023] Open
Abstract
Exosomal miRNA transfer is a mechanism for cell-cell communication that is important in the immune response, in the functioning of the nervous system and in cancer. Syncrip/hnRNPQ is a highly conserved RNA-binding protein that mediates the exosomal partition of a set of miRNAs. Here, we report that Syncrip's amino-terminal domain, which was previously thought to mediate protein-protein interactions, is a cryptic, conserved and sequence-specific RNA-binding domain, designated NURR (N-terminal unit for RNA recognition). The NURR domain mediates the specific recognition of a short hEXO sequence defining Syncrip exosomal miRNA targets, and is coupled by a non-canonical structural element to Syncrip's RRM domains to achieve high-affinity miRNA binding. As a consequence, Syncrip-mediated selection of the target miRNAs implies both recognition of the hEXO sequence by the NURR domain and binding of the RRM domains 5' to this sequence. This structural arrangement enables Syncrip-mediated selection of miRNAs with different seed sequences.
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Affiliation(s)
- Fruzsina Hobor
- Research Department of Structural and Molecular Biology, University College London, Darwin Building, Gower Street, London, WC1E 6XA, UK
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK
| | - Andre Dallmann
- Research Department of Structural and Molecular Biology, University College London, Darwin Building, Gower Street, London, WC1E 6XA, UK
- Department of Chemistry, Humboldt Universität zu Berlin, Brook-Taylor-Street 2, 12489, Berlin, Germany
| | - Neil J Ball
- Macromolecular Structure Laboratory, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Carla Cicchini
- Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Department of Cellular Biotechnologies and Haematology, Sapienza University of Rome, Viale Regina Elena 324, 00161, Rome, Italy
| | - Cecilia Battistelli
- Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Department of Cellular Biotechnologies and Haematology, Sapienza University of Rome, Viale Regina Elena 324, 00161, Rome, Italy
| | - Roksana W Ogrodowicz
- Structural Biology Science Technology Platform, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Evangelos Christodoulou
- Structural Biology Science Technology Platform, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Stephen R Martin
- Structural Biology Science Technology Platform, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Alfredo Castello
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, UK
| | - Marco Tripodi
- Istituto Pasteur Italia-Fondazione Cenci Bolognetti, Department of Cellular Biotechnologies and Haematology, Sapienza University of Rome, Viale Regina Elena 324, 00161, Rome, Italy
| | - Ian A Taylor
- Macromolecular Structure Laboratory, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK.
| | - Andres Ramos
- Research Department of Structural and Molecular Biology, University College London, Darwin Building, Gower Street, London, WC1E 6XA, UK.
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Efentakis P, Rizakou A, Christodoulou E, Chatzianastasiou A, López MG, León R, Balafas E, Kadoglou NPE, Tseti I, Skaltsa H, Kostomitsopoulos N, Iliodromitis EK, Valsami G, Andreadou I. Saffron (Crocus sativus) intake provides nutritional preconditioning against myocardial ischemia-reperfusion injury in Wild Type and ApoE (-/-) mice: Involvement of Nrf2 activation. Nutr Metab Cardiovasc Dis 2017; 27:919-929. [PMID: 28964663 DOI: 10.1016/j.numecd.2017.08.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 07/20/2017] [Accepted: 08/14/2017] [Indexed: 02/05/2023]
Abstract
BACKGROUND AND AIMS Saffron is an antioxidant herbal derivative; however, its efficacy as a nutritional cardioprotective agent has not been fully elucidated. We investigated the cardioprotective properties of a standardized saffron aqueous extract (SFE) against ischemia/reperfusion (I/R) injury in Wild-Type (WT) and ApoE(-/-) mice and the underlying molecular mechanisms. METHODS AND RESULTS WT and ApoE(-/-) mice were subjected to 30 min I and 2 h R, with the following per os interventions for 4 weeks: 1) WT Control Group, receiving Water for Injection (WFI); 2) WT Crocus Group, receiving SFE at a dose of 60 mg/kg/day; 3) WT Crocus + Wort group, receiving SFE as described above and wortmannin at a dose of 60 μg/kg bolus 15 min before R; 4) ApoE(-/-) Control Group, receiving WFI; 5) ApoE(-/-) Crocus Group, receiving SFE at a dose of 60 mg/kg/day and 6) ApoE(-/-) Crocus + Wort: receiving SFE as described above and wortmannin at a dose of 60 μg/kg bolus, 15 min before R. Ischemic area/area at risk (I/R%) ratio was measured. Blood samples and ischemic myocardial tissue were collected at the 10th min of reperfusion for assessment of troponin I, malondialdehyde (MDA), nitrotyrosine (NT), p-eNOS, eNOS, p-Akt, Akt, p-p42/p-p44, p-GSK3β, GSK3β, IL-6, Nrf2, HO-1 and MnSOD expression. The effect of SFE on Nrf2 expression was also evaluated in vitro. SFE reduced infarct size in WT (16.15 ± 3.7% vs 41.57 ± 2.48%, ***p < 0.001) and in ApoE(-/-) mice (16.14 ± 1.47% vs 45.57 ± 1.73%, ***p < 0.001). The administration of wortmannin resulted in partial inhibition of the infarct size limitation efficacy of SFE (in both WT and Apo-E(-/-) mice). Mice receiving SFE showed increased levels of eNOS, p-Akt, p-ERK1/2, p-44/p-42 and p-GSK3β-Ser9 and reduced expression of IL-6 and iNOS; furthermore, SFE reduced the levels of MDA and NT. SFE induced Nrf2 expression and its downstream targets, HO-1 and MnSOD in the myocardium of the treated animals, and induced Nrf2 expression in vitro in a dose-dependent manner. CONCLUSIONS SFE limits myocardial infarction in Wild-Type and ApoE(-/-) mice in a multifaceted manner including activation of Akt/eNOS/ERK1/2/GSK3-β and through Nrf2 pathway, bestowing antioxidant protection against I/R.
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Affiliation(s)
- P Efentakis
- National and Kapodistrian University of Athens, Laboratory of Pharmacology, Faculty of Pharmacy, Athens, Greece
| | - A Rizakou
- National and Kapodistrian University of Athens, Laboratory of Pharmacology, Faculty of Pharmacy, Athens, Greece
| | - E Christodoulou
- National and Kapodistrian University of Athens, Laboratory of Biopharmaceutics, Faculty of Pharmacy, Athens, Greece
| | - A Chatzianastasiou
- National and Kapodistrian University of Athens, Laboratory of Pharmacology, Faculty of Pharmacy, Athens, Greece
| | - M G López
- Departamento de Farmacología y Terapéutica, Instituto Téofilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain
| | - R León
- Departamento de Farmacología y Terapéutica, Instituto Téofilo Hernando, Facultad de Medicina, Universidad Autónoma de Madrid, Madrid, Spain; Instituto de Investigación Sanitaria del Hospital Universitario la Princesa, Madrid, Spain
| | - E Balafas
- Academy of Athens Biomedical Research Foundation, Centre of Clinical Experimental Surgery and Translational Research, Biomedical Research Foundation, Athens, Greece
| | - N P E Kadoglou
- National and Kapodistrian University of Athens, Laboratory of Biopharmaceutics, Faculty of Pharmacy, Athens, Greece
| | - I Tseti
- Uni-Pharma S.A., Athens, Greece
| | - H Skaltsa
- National and Kapodistrian University of Athens, Department of Pharmacognocy and Chemistry of Natural Products, Faculty of Pharmacy, Athens, Greece
| | - N Kostomitsopoulos
- Academy of Athens Biomedical Research Foundation, Centre of Clinical Experimental Surgery and Translational Research, Biomedical Research Foundation, Athens, Greece
| | - E K Iliodromitis
- National and Kapodistrian University of Athens, Medical School, Second University Department of Cardiology, Athens, Greece
| | - G Valsami
- National and Kapodistrian University of Athens, Laboratory of Biopharmaceutics, Faculty of Pharmacy, Athens, Greece
| | - I Andreadou
- National and Kapodistrian University of Athens, Laboratory of Pharmacology, Faculty of Pharmacy, Athens, Greece.
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Batsos G, Parikakis E, Christodoulou E, Karagiannis D, Stefaniotou M. Long-term outcome following ranibizumab treatment for CNV related to ND: YAG-Laser macular injury. Acta Ophthalmol 2017. [DOI: 10.1111/j.1755-3768.2017.0f026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- G. Batsos
- Second Department of Ophthalmology; Ophthalmiatreio Eye Hospital of Athens; Athens Greece
| | - E. Parikakis
- Second Department of Ophthalmology; Ophthalmiatreio Eye Hospital of Athens; Athens Greece
| | - E. Christodoulou
- Department of Ophthalmology; University Hospital of Ioannina; Ioannina Greece
| | - D. Karagiannis
- Second Department of Ophthalmology; Ophthalmiatreio Eye Hospital of Athens; Athens Greece
| | - M. Stefaniotou
- Department of Ophthalmology; University Hospital of Ioannina; Ioannina Greece
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18
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Efentakis P, Rizakou A, Christodoulou E, Chatzianastasiou A, Lopez M, Leon R, Balafas E, Kadoglou N, Tseti I, Kostomitsopoulos N, Iliodromitis E, Valsami G, Andreadou I. P5324Saffron (Crocus sativus) intake provides nutritional preconditioning against myocardial ischemia-reperfusion injury in wild type and Apo-E(−/−) mice: involvement of Nrf2 activation. Eur Heart J 2017. [DOI: 10.1093/eurheartj/ehx493.p5324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Grivas TB, Burwell RG, Kechagias V, Mazioti C, Fountas A, Kolovou D, Christodoulou E. Idiopathic and normal lateral lumbar curves: muscle effects interpreted by 12th rib length asymmetry with pathomechanic implications for lumbar idiopathic scoliosis. Scoliosis Spinal Disord 2016; 11:35. [PMID: 27785474 PMCID: PMC5073422 DOI: 10.1186/s13013-016-0093-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Background The historical view of scoliosis as a primary rotation deformity led to debate about the pathomechanic role of paravertebral muscles; particularly multifidus, thought by some to be scoliogenic, counteracting, uncertain, or unimportant. Here, we address lateral lumbar curves (LLC) and suggest a pathomechanic role for quadrates lumborum, (QL) in the light of a new finding, namely of 12th rib bilateral length asymmetry associated with idiopathic and small non-scoliosis LLC. Methods Group 1: The postero-anterior spinal radiographs of 14 children (girls 9, boys 5) aged 9–18, median age 13 years, with right lumbar idiopathic scoliosis (IS) and right LLC less that 10°, were studied. The mean Cobb angle was 12° (range 5–22°). Group 2: In 28 children (girls 17, boys 11) with straight spines, postero-anterior spinal radiographs were evaluated similarly to the children with the LLC, aged 8–17, median age 13 years. The ratio of the right/left 12th rib lengths and it’s reliability was calculated. The difference of the ratio between the two groups was tested; and the correlation between the ratio and the Cobb angle estimated. Statistical analysis was done using the SPSS package. Results The ratio’s reliability study showed intra-observer +/−0,036 and the inter-observer error +/−0,042 respectively in terms of 95 % confidence limit of the error of measurements. The 12th rib was longer on the side of the curve convexity in 12 children with LLC and equal in two patients with lumbar scoliosis. The 12th rib ratios of the children with lumbar curve were statistically significantly greater than in those with straight spines. The correlation of the 12th rib ratio with Cobb angle was statistically significant. The 12th thoracic vertebrae show no axial rotation (or minimal) in the LLC and no rotation in the straight spine group. Conclusions It is not possible, at present, to determine whether the 12th convex rib lengthening is congenitally lengthened, induced mechanically, or both. Several small muscles are attached to the 12th ribs. We focus attention here on the largest of these muscles namely, QL. It has attachments to the pelvis, 12th ribs and transverse processes of lumbar vertebrae as origins and as insertions. Given increased muscle activity on the lumbar curve convexity and similar to the interpretations of earlier workers outlined above, we suggest two hypotheses, relatively increased activity of the right QL muscle causes the LLCs (first hypothesis); or counteracts the lumbar curvature as part of the body’s attempt to compensate for the curvature (second hypothesis). These hypotheses may be tested by electrical stimulation studies of QL muscles in subjects with lumbar IS by revealing respectively curve worsening or correction. We suggest that one mechanism leading to relatively increased length of the right 12 ribs is mechanotransduction in accordance with Wolff’s and Pauwels Laws.
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Affiliation(s)
- Theodoros B Grivas
- Department of Orthopaedics and Traumatology, "Tzaneio" General Hospital, Tzani and Afendouli 1, Piraeus, 18536 Greece
| | - R Geoffrey Burwell
- Centre for Spinal Studies and Surgery, Nottingham University Hospitals NHS Trust, Queen's Medical Centre Campus, Nottingham, UK
| | - Vasileios Kechagias
- Department of Orthopaedics and Traumatology, "Tzaneio" General Hospital, Tzani and Afendouli 1, Piraeus, 18536 Greece
| | - Christina Mazioti
- Department of Orthopaedics and Traumatology, "Tzaneio" General Hospital, Tzani and Afendouli 1, Piraeus, 18536 Greece
| | - Apostolos Fountas
- Department of Orthopaedics and Traumatology, "Tzaneio" General Hospital, Tzani and Afendouli 1, Piraeus, 18536 Greece
| | - Dimitra Kolovou
- Department of Radiology, "Tzaneio" General Hospital, Tzani and Afendouli 1 st, Piraeus, 18536 Greece
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Martino L, Holland L, Christodoulou E, Kunzelmann S, Esposito D, Rittinger K. The Biophysical Characterisation and SAXS Analysis of Human NLRP1 Uncover a New Level of Complexity of NLR Proteins. PLoS One 2016; 11:e0164662. [PMID: 27727326 PMCID: PMC5058472 DOI: 10.1371/journal.pone.0164662] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Accepted: 09/28/2016] [Indexed: 12/02/2022] Open
Abstract
NOD-like receptors represent an important class of germline-encoded pattern recognition receptors that play key roles in the regulation of inflammatory signalling pathways. They function as danger sensors and initiate inflammatory responses and the production of cytokines. Since NLR malfunction results in chronic inflammation and auto-immune diseases, there is a great interest in understanding how they work on a molecular level. To date, a lot of insight into the biological functions of NLRs is available but biophysical and structural studies have been hampered by the difficulty to produce soluble and stable recombinant NLR proteins. NLRP1 is an inflammasome forming NLR that is believed to be activated by binding to MDP and induces activation of caspase 1. Here, we report the identification of a soluble fragment of NLRP1 that contains the NACHT oligomerization domain and the putative MDP-sensing LRR domain. We describe the biophysical and biochemical characterization of this construct and a SEC-SAXS analysis that allowed the calculation of a low resolution molecular envelope. Our data indicate that the protein is constitutively bound to ATP with a negligible ability to hydrolyse the triphosphate nucleotide and that it adopts a monomeric extended conformation that is reminiscent of the structure adopted by NLRC4 in the inflammasome complex. Furthermore, we show that the presence of MDP is not sufficient to promote self-oligomerization of the NACHT-LRR fragment suggesting that MDP may either bind to regions outside the NACHT-LRR module or that it may not be the natural ligand of NLRP1. Taken together, our data suggest that the NLRP1 mechanism of action differs from that recently reported for other NLRs.
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Affiliation(s)
- Luigi Martino
- Molecular Structure of Cell Signalling Laboratory, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, United Kingdom
| | - Louise Holland
- Molecular Structure of Cell Signalling Laboratory, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, United Kingdom
| | - Evangelos Christodoulou
- Structural Biology Science Technology Platform, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, United Kingdom
| | - Simone Kunzelmann
- Structural Biology Science Technology Platform, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, United Kingdom
| | - Diego Esposito
- Molecular Structure of Cell Signalling Laboratory, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, United Kingdom
| | - Katrin Rittinger
- Molecular Structure of Cell Signalling Laboratory, The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, United Kingdom
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Koliopoulos MG, Esposito D, Christodoulou E, Taylor IA, Rittinger K. Functional role of TRIM E3 ligase oligomerization and regulation of catalytic activity. EMBO J 2016; 35:1204-18. [PMID: 27154206 PMCID: PMC4864278 DOI: 10.15252/embj.201593741] [Citation(s) in RCA: 123] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Accepted: 04/06/2016] [Indexed: 12/30/2022] Open
Abstract
TRIM E3 ubiquitin ligases regulate a wide variety of cellular processes and are particularly important during innate immune signalling events. They are characterized by a conserved tripartite motif in their N-terminal portion which comprises a canonical RING domain, one or two B-box domains and a coiled-coil region that mediates ligase dimerization. Self-association via the coiled-coil has been suggested to be crucial for catalytic activity of TRIMs; however, the precise molecular mechanism underlying this observation remains elusive. Here, we provide a detailed characterization of the TRIM ligases TRIM25 and TRIM32 and show how their oligomeric state is linked to catalytic activity. The crystal structure of a complex between the TRIM25 RING domain and an ubiquitin-loaded E2 identifies the structural and mechanistic features that promote a closed E2~Ub conformation to activate the thioester for ubiquitin transfer allowing us to propose a model for the regulation of activity in the full-length protein. Our data reveal an unexpected diversity in the self-association mechanism of TRIMs that might be crucial for their biological function.
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Affiliation(s)
- Marios G Koliopoulos
- Mill Hill LaboratoryMolecular Structure of Cell Signalling LaboratoryThe Francis Crick InstituteLondonUK
| | - Diego Esposito
- Mill Hill LaboratoryMolecular Structure of Cell Signalling LaboratoryThe Francis Crick InstituteLondonUK
| | | | - Ian A Taylor
- Mill Hill LaboratoryMacromolecular Structure LaboratoryThe Francis Crick InstituteLondonUK
| | - Katrin Rittinger
- Mill Hill LaboratoryMolecular Structure of Cell Signalling LaboratoryThe Francis Crick InstituteLondonUK
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Goodsitt M, Chan H, Watcharotone K, Nan B, Christodoulou E. SU-C-206-02: Estimating Coronary Artery Plaque Composition with a Combined Dual-Energy and Single-Energy QCT Optimization Model. Med Phys 2016. [DOI: 10.1118/1.4955584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Christodoulou E, Chinthakunta S, Reddy D, Khalil S, Apostolou T, Drees P, Kafchitsas K. Axial pullout strength comparison of different screw designs: fenestrated screw, dual outer diameter screw and standard pedicle screw. Scoliosis 2015; 10:15. [PMID: 25949274 PMCID: PMC4422437 DOI: 10.1186/s13013-015-0039-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Accepted: 04/19/2015] [Indexed: 11/30/2022]
Abstract
Background The pullout strength of pedicle screws is influenced by many factors, including diameter of the screws, implant design, and augmentation with bone cement such as PMMA. In the present study, the pullout strength of an innovative fenestrated screw augmented with PMMA was investigated and was compared to unaugmented fenestrated, standard and dual outer diameter screw. Methods Twenty four thoracolumbar vertebrae (T10-L5, age 60 to 70 years) from three cadavers were implanted with the four different pedicle screws. Twelve screws of each type were instrumented into either left or right pedicle with standard screw paired with unaugmented and dual outer diameter screw paired with augmented fenestrated screw in any given vertebra. Axial pullout testing was conducted at a rate of 5 mm/min. Force to failure (Newtons) for each pedicle screw was recorded. Results The augmented fenestrated screws had the highest pullout strength, which represented an average increase of 149%, 141%, and 78% in comparison to unaugmented, standard, and dual outer diameter screws, respectively. Pullout strength of unaugmented screws was comparable to that of standard screws, however it was significantly lower than dual outer diameter screws. Conclusions Fenestrated screws augmented with PMMA improve the fixation strength and result in significantly higher pullout strength compared to dual outer diameter, standard and unaugmented fenestrated screws. Screws with dual outer diameter provided enhanced bone-screw purchase and may be considered as an alternative technique to increase the bone-screw interface in cases where augmentation using bone cement is not feasible. Unaugmented screws can be left in the pedicle even without cement and provide similar pullout strength to standard screws.
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Affiliation(s)
| | | | - Divya Reddy
- Globus Medical Inc., Ave 2560 General Armistead Ave, Audubon, PA 19403 USA
| | - Saif Khalil
- Globus Medical Inc., Ave 2560 General Armistead Ave, Audubon, PA 19403 USA
| | | | - Philipp Drees
- Universitätsmedizin Mainz, Langenbeckstr, 1 55131 Germany
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Hantelius V, Steingrimsson S, Christodoulou E, Szabó Z. Implementation of Bright Light Therapy as Adjuvant Treatment for Depression and Insomnia Among Inpatients. Eur Psychiatry 2015. [DOI: 10.1016/s0924-9338(15)30501-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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Withers-Martinez C, Strath M, Hackett F, Haire LF, Howell SA, Walker PA, Christodoulou E, Dodson GG, Blackman MJ. Erratum: Corrigendum: The malaria parasite egress protease SUB1 is a calcium-dependent redox switch subtilisin. Nat Commun 2014. [PMCID: PMC5784272 DOI: 10.1038/ncomms5031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Kado R, Emily S, Lewis E, Goodsitt M, Christodoulou E, Kazerooni E, McCune W. OP0055 Utility and Associated Risk of Pulmonary Embolism CT Scans in the Michigan Lupus Cohort. Ann Rheum Dis 2014. [DOI: 10.1136/annrheumdis-2014-eular.2406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Ibrahim M, Parmar H, Christodoulou E, Mukherji S. Raise the bar and lower the dose: current and future strategies for radiation dose reduction in head and neck imaging. AJNR Am J Neuroradiol 2014; 35:619-24. [PMID: 23449649 DOI: 10.3174/ajnr.a3473] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
SUMMARY Technologic advances in CT have generated a dramatic increase in the number of CT studies, with a resultant increase in the radiation dose related to CT scanning. Such increase in radiation dose is becoming a concern for the radiology community, especially with increasing public awareness of the dose burden related to examinations. To cope with the increase in CT-related radiation exposure, it is becoming necessary to optimize CT imaging protocols and apply radiation dose reduction techniques to ensure the best imaging with the lowest radiation dose.
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Affiliation(s)
- M Ibrahim
- From the University of Michigan Health System, Ann Arbor, Michigan
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Schwefel D, Groom HCT, Boucherit VC, Christodoulou E, Walker PA, Stoye JP, Bishop KN, Taylor IA. Structural basis of lentiviral subversion of a cellular protein degradation pathway. Nature 2013; 505:234-8. [PMID: 24336198 PMCID: PMC3886899 DOI: 10.1038/nature12815] [Citation(s) in RCA: 98] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Accepted: 10/28/2013] [Indexed: 12/20/2022]
Abstract
Lentiviruses contain accessory genes that have evolved to counteract the effects of host cellular defence proteins that inhibit productive infection. One such restriction factor, SAMHD1, inhibits human immunodeficiency virus (HIV)-1 infection of myeloid-lineage cells as well as resting CD4(+) T cells by reducing the cellular deoxynucleoside 5'-triphosphate (dNTP) concentration to a level at which the viral reverse transcriptase cannot function. In other lentiviruses, including HIV-2 and related simian immunodeficiency viruses (SIVs), SAMHD1 restriction is overcome by the action of viral accessory protein x (Vpx) or the related viral protein r (Vpr) that target and recruit SAMHD1 for proteasomal degradation. The molecular mechanism by which these viral proteins are able to usurp the host cell's ubiquitination machinery to destroy the cell's protection against these viruses has not been defined. Here we present the crystal structure of a ternary complex of Vpx with the human E3 ligase substrate adaptor DCAF1 and the carboxy-terminal region of human SAMHD1. Vpx is made up of a three-helical bundle stabilized by a zinc finger motif, and wraps tightly around the disc-shaped DCAF1 molecule to present a new molecular surface. This adapted surface is then able to recruit SAMHD1 via its C terminus, making it a competent substrate for the E3 ligase to mark for proteasomal degradation. The structure reported here provides a molecular description of how a lentiviral accessory protein is able to subvert the cell's normal protein degradation pathway to inactivate the cellular viral defence system.
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Affiliation(s)
- David Schwefel
- Division of Molecular Structure, MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, UK
| | - Harriet C T Groom
- Division of Virology, MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, UK
| | - Virginie C Boucherit
- Division of Virology, MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, UK
| | - Evangelos Christodoulou
- Division of Molecular Structure, MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, UK
| | - Philip A Walker
- Division of Molecular Structure, MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, UK
| | - Jonathan P Stoye
- Division of Virology, MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, UK
| | - Kate N Bishop
- Division of Virology, MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, UK
| | - Ian A Taylor
- Division of Molecular Structure, MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, UK
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29
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Stieglitz B, Rana RR, Koliopoulos MG, Morris-Davies AC, Schaeffer V, Christodoulou E, Howell S, Brown NR, Dikic I, Rittinger K. Structural basis for ligase-specific conjugation of linear ubiquitin chains by HOIP. Nature 2013; 503:422-426. [PMID: 24141947 PMCID: PMC3838313 DOI: 10.1038/nature12638] [Citation(s) in RCA: 150] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Accepted: 09/05/2013] [Indexed: 12/18/2022]
Abstract
Linear ubiquitin chains are important regulators of cellular signaling pathways that control innate immunity and inflammation through NF-κB activation and protection against TNFα-induced apoptosis1-5. They are synthesized by HOIP, which belongs to the RBR (RING-between-RING) family of E3 ligases and is the catalytic component of LUBAC (linear ubiquitin chain assembly complex), a multi-subunit E3 ligase6. RBR family members act as RING/HECT hybrids, employing RING1 to recognize ubiquitin-loaded E2 while a conserved cysteine in RING2 subsequently forms a thioester intermediate with the transferred or “donor” ubiquitin7. Here we report the crystal structure of the catalytic core of HOIP in its apo form and in complex with ubiquitin. The C-terminal portion of HOIP adopts a novel fold that, together with a zinc finger, forms an ubiquitin-binding platform which orients the acceptor ubiquitin and positions its α-amino group for nucleophilic attack on the E3~ubiquitin thioester. The carboxy-terminal tail of a second ubiquitin molecule is located in close proximity to the catalytic cysteine providing a unique snapshot of the ubiquitin transfer complex containing both donor and acceptor ubiquitin. These interactions are required for activation of the NF-kB pathway in vivo and explain the determinants of linear ubiquitin chain specificity by LUBAC.
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Affiliation(s)
- Benjamin Stieglitz
- Division of Molecular Structure, MRC-National Institute for Medical Research, The Ridgeway, London NW7 1AA, UK
| | - Rohini R Rana
- Division of Molecular Structure, MRC-National Institute for Medical Research, The Ridgeway, London NW7 1AA, UK
| | - Marios G Koliopoulos
- Division of Molecular Structure, MRC-National Institute for Medical Research, The Ridgeway, London NW7 1AA, UK
| | - Aylin C Morris-Davies
- Division of Molecular Structure, MRC-National Institute for Medical Research, The Ridgeway, London NW7 1AA, UK
| | - Veronique Schaeffer
- Institute of Biochemistry II, Goethe University, School of Medicine, Theodor-Stern-Kai 7, D-60590 Frankfurt (Main), Germany
| | - Evangelos Christodoulou
- Division of Molecular Structure, MRC-National Institute for Medical Research, The Ridgeway, London NW7 1AA, UK
| | - Steven Howell
- Division of Molecular Structure, MRC-National Institute for Medical Research, The Ridgeway, London NW7 1AA, UK
| | - Nicholas R Brown
- Division of Molecular Structure, MRC-National Institute for Medical Research, The Ridgeway, London NW7 1AA, UK
| | - Ivan Dikic
- Institute of Biochemistry II, Goethe University, School of Medicine, Theodor-Stern-Kai 7, D-60590 Frankfurt (Main), Germany
| | - Katrin Rittinger
- Division of Molecular Structure, MRC-National Institute for Medical Research, The Ridgeway, London NW7 1AA, UK
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30
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Stieglitz B, Morris-Davies AC, Koliopoulos MG, Christodoulou E, Rittinger K. LUBAC synthesizes linear ubiquitin chains via a thioester intermediate. EMBO Rep 2012; 13:840-6. [PMID: 22791023 PMCID: PMC3432797 DOI: 10.1038/embor.2012.105] [Citation(s) in RCA: 175] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2012] [Revised: 06/21/2012] [Accepted: 06/22/2012] [Indexed: 01/31/2023] Open
Abstract
The linear ubiquitin chain assembly complex (LUBAC) is a RING E3 ligase that regulates immune and inflammatory signalling pathways. Unlike classical RING E3 ligases, LUBAC determines the type of ubiquitin chain being formed, an activity normally associated with the E2 enzyme. We show that the RING-in-between-RING (RBR)-containing region of HOIP--the catalytic subunit of LUBAC--is sufficient to generate linear ubiquitin chains. However, this activity is inhibited by the N-terminal portion of the molecule, an inhibition that is released upon complex formation with HOIL-1L or SHARPIN. Furthermore, we demonstrate that HOIP transfers ubiquitin to the substrate through a thioester intermediate formed by a conserved cysteine in the RING2 domain, supporting the notion that RBR ligases act as RING/HECT hybrids.
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Affiliation(s)
- Benjamin Stieglitz
- Division of Molecular Structure, MRC-National Institute for Medical Research, The Ridgeway, London NW7 1AA, UK
| | - Aylin C Morris-Davies
- Division of Molecular Structure, MRC-National Institute for Medical Research, The Ridgeway, London NW7 1AA, UK
| | - Marios G Koliopoulos
- Division of Molecular Structure, MRC-National Institute for Medical Research, The Ridgeway, London NW7 1AA, UK
| | - Evangelos Christodoulou
- Division of Molecular Structure, MRC-National Institute for Medical Research, The Ridgeway, London NW7 1AA, UK
| | - Katrin Rittinger
- Division of Molecular Structure, MRC-National Institute for Medical Research, The Ridgeway, London NW7 1AA, UK
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31
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Givissis P, Agathangelidis F, Christodoulou E, Christodoulou A. Chondroblastoma of the femoral head disrupting the articular cartilage. Description of a novel surgical technique. Acta Orthop Belg 2012; 78:414-417. [PMID: 22822587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Chondroblastoma is a rare benign tumour. Involvement of the femoral head may often lead to a delayed diagnosis. We present the case of a 15-year-old patient with right hip pain which was first attributed to adductor tendinitis. Following aggravation of the symptoms, thorough investigation including a CT-guided biopsy, revealed the diagnosis of chondroblastoma of the femoral head. Removal of the lesion based on the techniques described in literature was not possible, mainly because the articular cartilage was breached. A novel surgical technique was used in order to address the rare location and behaviour of the tumour. This technique offered the patient pain relief and return to his previous every day and sports activities. No recurrence was seen at two years follow-up.
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Affiliation(s)
- Panagiotis Givissis
- 1st Department of Orthopaedics, G. Papanikolaou General Hospital, Aristotle University of Thessaloniki, Greece
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32
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Goodsitt M, Chan H, Christodoulou E, Larson S. TH-E-217BCD-10: The Effect of Model Based Iterative Reconstruction (GE-VEO) on the CT Numbers and Noise of Both Small Lung Nodules and Large Homogeneous (heart and Spongiosa) Regions in an Anthropomorphic Chest Phantom. Med Phys 2012. [DOI: 10.1118/1.4736384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Kryshtafovych A, Moult J, Bartual SG, Bazan JF, Berman H, Casteel DE, Christodoulou E, Everett JK, Hausmann J, Heidebrecht T, Hills T, Hui R, Hunt JF, Seetharaman J, Joachimiak A, Kennedy MA, Kim C, Lingel A, Michalska K, Montelione GT, Otero JM, Perrakis A, Pizarro JC, van Raaij MJ, Ramelot TA, Rousseau F, Tong L, Wernimont AK, Young J, Schwede T. Target highlights in CASP9: Experimental target structures for the critical assessment of techniques for protein structure prediction. Proteins 2011; 79 Suppl 10:6-20. [PMID: 22020785 PMCID: PMC3692002 DOI: 10.1002/prot.23196] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
One goal of the CASP community wide experiment on the critical assessment of techniques for protein structure prediction is to identify the current state of the art in protein structure prediction and modeling. A fundamental principle of CASP is blind prediction on a set of relevant protein targets, that is, the participating computational methods are tested on a common set of experimental target proteins, for which the experimental structures are not known at the time of modeling. Therefore, the CASP experiment would not have been possible without broad support of the experimental protein structural biology community. In this article, several experimental groups discuss the structures of the proteins which they provided as prediction targets for CASP9, highlighting structural and functional peculiarities of these structures: the long tail fiber protein gp37 from bacteriophage T4, the cyclic GMP-dependent protein kinase Iβ dimerization/docking domain, the ectodomain of the JTB (jumping translocation breakpoint) transmembrane receptor, Autotaxin in complex with an inhibitor, the DNA-binding J-binding protein 1 domain essential for biosynthesis and maintenance of DNA base-J (β-D-glucosyl-hydroxymethyluracil) in Trypanosoma and Leishmania, an so far uncharacterized 73 residue domain from Ruminococcus gnavus with a fold typical for PDZ-like domains, a domain from the phycobilisome core-membrane linker phycobiliprotein ApcE from Synechocystis, the heat shock protein 90 activators PFC0360w and PFC0270w from Plasmodium falciparum, and 2-oxo-3-deoxygalactonate kinase from Klebsiella pneumoniae.
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Affiliation(s)
- Andriy Kryshtafovych
- Genome Center, University of California-Davis, 451 Health Sciences Drive, Davis, CA 95616, USA
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Goodsitt M, Larson S, Christodoulou E. TH-E-110-11: The Effect of Region-Of-Interest Z-Axis Collimation on the Image Quality of a Commercial Cone Beam CT Imaging System. Med Phys 2011. [DOI: 10.1118/1.3613595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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35
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Christodoulou E, Goodsitt M. TH-E-211-04: ICRP-103 Based Gender and Age-Specific DLP to Effective Dose Conversion Factors (k). Med Phys 2011. [DOI: 10.1118/1.3613599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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36
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Heidebrecht T, Christodoulou E, Chalmers MJ, Jan S, Ter Riet B, Grover RK, Joosten RP, Littler D, van Luenen H, Griffin PR, Wentworth P, Borst P, Perrakis A. The structural basis for recognition of base J containing DNA by a novel DNA binding domain in JBP1. Nucleic Acids Res 2011; 39:5715-28. [PMID: 21415010 PMCID: PMC3141245 DOI: 10.1093/nar/gkr125] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The J-binding protein 1 (JBP1) is essential for biosynthesis and maintenance of DNA base-J (β-d-glucosyl-hydroxymethyluracil). Base-J and JBP1 are confined to some pathogenic protozoa and are absent from higher eukaryotes, prokaryotes and viruses. We show that JBP1 recognizes J-containing DNA (J-DNA) through a 160-residue domain, DB-JBP1, with 10 000-fold preference over normal DNA. The crystal structure of DB-JBP1 revealed a helix-turn-helix variant fold, a 'helical bouquet' with a 'ribbon' helix encompassing the amino acids responsible for DNA binding. Mutation of a single residue (Asp525) in the ribbon helix abrogates specificity toward J-DNA. The same mutation renders JBP1 unable to rescue the targeted deletion of endogenous JBP1 genes in Leishmania and changes its distribution in the nucleus. Based on mutational analysis and hydrogen/deuterium-exchange mass-spectrometry data, a model of JBP1 bound to J-DNA was constructed and validated by small-angle X-ray scattering data. Our results open new possibilities for targeted prevention of J-DNA recognition as a therapeutic intervention for parasitic diseases.
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Affiliation(s)
- Tatjana Heidebrecht
- Division of Biochemistry, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
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37
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Hausmann J, Kamtekar S, Christodoulou E, Day JE, Wu T, Fulkerson Z, Albers HMHG, van Meeteren LA, Houben AJS, van Zeijl L, Jansen S, Andries M, Hall T, Pegg LE, Benson TE, Kasiem M, Harlos K, Kooi CWV, Smyth SS, Ovaa H, Bollen M, Morris AJ, Moolenaar WH, Perrakis A. Structural basis of substrate discrimination and integrin binding by autotaxin. Nat Struct Mol Biol 2011; 18:198-204. [PMID: 21240271 PMCID: PMC3064516 DOI: 10.1038/nsmb.1980] [Citation(s) in RCA: 217] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2010] [Accepted: 11/08/2010] [Indexed: 12/11/2022]
Abstract
Autotaxin (ATX) or ecto-nucleotide pyrophosphatase/phosphodiesterase-2 (ENPP2) is a secreted lysophospholipase D that generates the lipid mediator lysophosphatidic acid (LPA), a mitogen and chemo-attractant for many cell types. ATX-LPA signaling has roles in various pathologies including tumour progression and inflammation. However, the molecular basis of substrate recognition and catalysis, and the mechanism of interaction with target cells, has been elusive. Here we present the crystal structure of ATX, alone and in complex with a small-molecule inhibitor. We identify a hydrophobic lipid-binding pocket and map key residues required for catalysis and selection between nucleotide and phospholipid substrates. We show that ATX interacts with cell-surface integrins via its N-terminal somatomedin-B-like domains, using an atypical mechanism. Our results define determinants of substrate discrimination by the ENPP family, suggest how ATX promotes localized LPA signaling, and enable new approaches to target ATX with small-molecule therapeutics.
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Affiliation(s)
- Jens Hausmann
- Division of Biochemistry, The Netherlands Cancer Institute, Amsterdam, The Netherlands
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38
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Hausmann J, Christodoulou E, Kasiem M, De Marco V, van Meeteren LA, Moolenaar WH, Axford D, Owen RL, Evans G, Perrakis A. Mammalian cell expression, purification, crystallization and microcrystal data collection of autotaxin/ENPP2, a secreted mammalian glycoprotein. Acta Crystallogr Sect F Struct Biol Cryst Commun 2010; 66:1130-5. [PMID: 20823545 PMCID: PMC2935246 DOI: 10.1107/s1744309110032938] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2010] [Accepted: 08/16/2010] [Indexed: 11/15/2022]
Abstract
Autotaxin, a four-domain ∼100 kDa mammalian glycoprotein, was expressed in stably transfected mammalian cells, purified from the medium and crystallized. Diffraction data from micrometre-thick crystal plates were collected on various European synchrotron beamlines and are presented and analysed. Autotaxin (ATX or ENPP2) is a secreted glycosylated mammalian enzyme that exhibits lysophospholipase D activity, hydrolyzing lysophosphatidylcholine to the signalling lipid lysophosphatidic acid. ATX is an ∼100 kDa multi-domain protein encompassing two N-terminal somatomedin B-like domains, a central catalytic phosphodiesterase domain and a C-terminal nuclease-like domain. Protocols for the efficient expression of ATX from stably transfected mammalian HEK293 cells in amounts sufficient for crystallographic studies are reported. Purification resulted in protein that crystallized readily, but various attempts to grow crystals suitable in size for routine crystallographic structure determination were not successful. However, the available micrometre-thick plates diffracted X-rays beyond 2.0 Å resolution and allowed the collection of complete diffraction data to about 2.6 Å resolution. The problems encountered and the current advantages and limitations of diffraction data collection from thin crystal plates are discussed.
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Affiliation(s)
- Jens Hausmann
- Division of Biochemistry B8, The Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
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39
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Goodsitt M, Christodoulou E, Larson S. TU-E-201B-09: Accuracies of the Monochromatic CT Numbers and Effective Atomic Numbers Generated with the Rapid KVp Switching DE GE HD750 CT Scanner. Med Phys 2010. [DOI: 10.1118/1.3469319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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40
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De Marco V, Gillespie PJ, Li A, Karantzelis N, Christodoulou E, Klompmaker R, van Gerwen S, Fish A, Petoukhov MV, Iliou MS, Lygerou Z, Medema RH, Blow JJ, Svergun DI, Taraviras S, Perrakis A. Quaternary structure of the human Cdt1-Geminin complex regulates DNA replication licensing. Proc Natl Acad Sci U S A 2009; 106:19807-12. [PMID: 19906994 PMCID: PMC2775996 DOI: 10.1073/pnas.0905281106] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2009] [Indexed: 01/12/2023] Open
Abstract
All organisms need to ensure that no DNA segments are rereplicated in a single cell cycle. Eukaryotes achieve this through a process called origin licensing, which involves tight spatiotemporal control of the assembly of prereplicative complexes (pre-RCs) onto chromatin. Cdt1 is a key component and crucial regulator of pre-RC assembly. In higher eukaryotes, timely inhibition of Cdt1 by Geminin is essential to prevent DNA rereplication. Here, we address the mechanism of DNA licensing inhibition by Geminin, by combining X-ray crystallography, small-angle X-ray scattering, and functional studies in Xenopus and mammalian cells. Our findings show that the Cdt1:Geminin complex can exist in two distinct forms, a "permissive" heterotrimer and an "inhibitory" heterohexamer. Specific Cdt1 residues, buried in the heterohexamer, are important for licensing. We postulate that the transition between the heterotrimer and the heterohexamer represents a molecular switch between licensing-competent and licensing-defective states.
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Affiliation(s)
- V. De Marco
- Department of Biochemistry, Netherlands Cancer Institute, Plesmanlaan 121, 1066CX Amsterdam, The Netherlands
| | - P. J. Gillespie
- Wellcome Trust Centre for Gene Regulation and Expression, College of Life Sciences, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - A. Li
- Wellcome Trust Centre for Gene Regulation and Expression, College of Life Sciences, University of Dundee, Dundee DD1 5EH, United Kingdom
| | | | - E. Christodoulou
- Department of Biochemistry, Netherlands Cancer Institute, Plesmanlaan 121, 1066CX Amsterdam, The Netherlands
| | - R. Klompmaker
- Department of Medical Oncology and Cancer Genomics Center, Laboratory of Experimental Oncology, University Medical Center Utrecht, Universiteitsweg 100, 3584CG Utrecht, The Netherlands; and
| | - S. van Gerwen
- Department of Biochemistry, Netherlands Cancer Institute, Plesmanlaan 121, 1066CX Amsterdam, The Netherlands
| | - A. Fish
- Department of Biochemistry, Netherlands Cancer Institute, Plesmanlaan 121, 1066CX Amsterdam, The Netherlands
| | - M. V. Petoukhov
- European Molecular Biology Laboratory, Hamburg Outstation, Notkestrasse 85, D-22603 Hamburg, Germany
| | - M. S. Iliou
- Biology, Medical School, University of Patras, 26500 Rio, Patras, Greece
| | - Z. Lygerou
- Biology, Medical School, University of Patras, 26500 Rio, Patras, Greece
| | - R. H. Medema
- Department of Medical Oncology and Cancer Genomics Center, Laboratory of Experimental Oncology, University Medical Center Utrecht, Universiteitsweg 100, 3584CG Utrecht, The Netherlands; and
| | - J. J. Blow
- Wellcome Trust Centre for Gene Regulation and Expression, College of Life Sciences, University of Dundee, Dundee DD1 5EH, United Kingdom
| | - D. I. Svergun
- European Molecular Biology Laboratory, Hamburg Outstation, Notkestrasse 85, D-22603 Hamburg, Germany
| | | | - A. Perrakis
- Department of Biochemistry, Netherlands Cancer Institute, Plesmanlaan 121, 1066CX Amsterdam, The Netherlands
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Vernadakis S, Rallis G, Danias N, Serafimidis C, Christodoulou E, Troullinakis M, Legakis N, Peros G. Metastatic melanoma of the gallbladder: An unusual clinical presentation of acute cholecystitis. World J Gastroenterol 2009; 15:3434-6. [PMID: 19610148 PMCID: PMC2712908 DOI: 10.3748/wjg.15.3434] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Metastatic disease from cutaneous melanoma can affect all organs of the body, and varies in its biological behavior and clinical presentation. We present the case of a 58-year-old man who arrived at our clinic with acute abdominal pain, which, after investigation, was diagnosed as acute cholecystitis. The patient underwent laparotomy and cholecystectomy. Two years ago, he underwent surgical removal of a primary cutaneous melanoma on his right upper back. Pathological examination revealed the presence of malignant melanoma with a metastatic lesion of the gallbladder.
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Vernadakis S, Christodoulou E, Treckmann J, Saner F, Paul A, Mathe Z. Pseudoaneurysmal rupture of the common hepatic artery into the biliodigestive anastomosis. A rare cause of gastrointestinal bleeding. JOP 2009; 10:441-444. [PMID: 19581753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
CONTEXT Pseudoaneurysm of the hepatic artery after a pancreaticoduodenectomy is a serious complication, which should always be considered in the differential diagnosis when late bleeding has occurred. CASE REPORT We report a case of pseudoaneurysmal rupture of the common hepatic artery into the biliodigestive anastomosis. A 55 year old female patient with a history of pancreatic head cancer underwent a pylorus preserving pancreaticoduodenectomy at our hospital in September 2008. Six days postoperatively the patient underwent surgery because of sentinel bleeding of a portal vein branch. On the 40th postoperative day she presented melena. Upper gastrointestinal endoscopy indicated bleeding near the biliodigestive anastomosis. An emergency angiography demonstrated a pseudoaneurysm of the common hepatic artery. Transcatheter arterial embolization was performed and a hemodynamic stabilization of the patient was achieved. Six days after the embolization the patient developed hemorrhagic shock and an urgent relaparotomy was carried out. The explorative laparotomy revealed bleeding of the common hepatic artery into the biliodigestive anastomosis in the form of an arteriointestinal fistula. The anastomosis was opened, the ruptured pseudoaneurysm was sutured, and a new biliodigestive anastomosis was made. The patient has been well for two months with good liver function, without rebleeding. CONCLUSION This case illustrates the occurrence of a rare complication (rupture of a hepatic artery pseudoaneurysm) inside the biliodigestive anastomosis after pancreaticoduodenectomy, appearing as upper gastrointestinal bleeding. Different modalities such as transarterial embolization and the use of stents give promising results, but ligation of the pseudoaneurysm and repair of the intestinal communication is also an effective modality of treatment.
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Affiliation(s)
- Spiridon Vernadakis
- Department of General, Visceral and Transplantation Surgery, University Hospital, Essen, Germany.
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43
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Christodoulou E, Goodsitt M, Bailey B, Young R. MO-FF-A4-02: Effects of Added X-Ray Beam Cu Filtration On Image Quality and Patient Dose in Digital Radiography. Med Phys 2009. [DOI: 10.1118/1.3182296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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44
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Goodsitt M, Christodoulou E. SU-EE-A4-01: Evaluation of Noise and SDNR Characteristics of Blended ASIR and FBP Images Obtained with the GE Discovery CT 750 HD Scanner. Med Phys 2009. [DOI: 10.1118/1.3181111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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45
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Larson S, Goodsitt M, Christodoulou E. SU-FF-I-61: Gypsum Barrier Shielding Estimates for Two Cone-Beam CT Systems Dedicated to Head Imaging. Med Phys 2009. [DOI: 10.1118/1.3181181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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46
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Vernadakis S, Kaiser GM, Christodoulou E, Mathe Z, Troullinakis M, Bankfalvi A, Paul A. Enormous serous microcystic adenoma of the pancreas. JOP 2009; 10:332-334. [PMID: 19454830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Serous microcystic adenomas or serous cystadenomas are rare and account for 1-2% of the exocrine neoplasms of the pancreas. Recently, due to the improvements in imaging techniques, they have been identified more frequently. We present the case of a patient in whom a serous microcystic adenoma, 26 cm in diameter, was found incidentally in the pancreas, the largest reported in the literature thus far. Pylorus-preserving pancreaticoduodenectomy was performed, combined with a right hemicolectomy because of the tumor localization. Despite their size, the resection of serous microcystic adenomas, even of that magnitude, is operatively efficient and should always be taken into consideration when examining therapeutic options.
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Affiliation(s)
- Spiridon Vernadakis
- Department of General, Visceral and Transplantation Surgery, University Hospital Essen, Essen, Germany.
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47
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Christodoulou E, Goodsitt M, Larson S. SU-GG-I-73: Investigation of the Relationship Between the Contrast-Detail Figure of Merit IQFinv and Three Characteristic Parameters of the Contrast-Detail Curve. Med Phys 2008. [DOI: 10.1118/1.2961471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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48
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Larson S, Goodsitt M, Christodoulou E, Young R. MO-E-332-05: The Effect of Copper Beam Filtration On the Transmission of Scattered X-Rays Through a Typical Lead Barrier. Med Phys 2008. [DOI: 10.1118/1.2962404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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49
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Goodsitt M, Christodoulou E, Larson S, Kazerooni E, Bogot N, Frank L. TU-EE-A4-01: Bismuth Shields Vs. MAs Reduction for Decreased Radiation Dose to Breasts in CT Examinations. Med Phys 2008. [DOI: 10.1118/1.2962623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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50
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Alspaugh J, Christodoulou E, Goodsitt M, Stayman J. TH-D-L100J-04: Dose and Image Quality of Flat-Panel Detector Volume Computed Tomography for Sinus Imaging. Med Phys 2007. [DOI: 10.1118/1.2761694] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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