1
|
Li Z. A molecular arm: the molecular bending-unbending mechanism of integrin. Biomech Model Mechanobiol 2024; 23:781-792. [PMID: 38308770 DOI: 10.1007/s10237-023-01805-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Accepted: 12/13/2023] [Indexed: 02/05/2024]
Abstract
The balance of integrin activation and deactivation regulates its function and mediates cell behaviors. Mechanical force triggers the unbending and activation of integrin. However, how an activated and extended integrin spontaneously bends back is unclear. I performed all-atom molecular dynamics simulations on an integrin or its subunits to reveal the bending-unbending mechanism of integrin. According to the simulations, the integrin structure works like a human arm. The integrin α subunit serves as the bones, while the β leg serves as the bicep. The integrin extension results in the stretching of the β leg, and the extended integrin spontaneously bends as a consequence of the contraction of the β leg. This study provides new insights into the mechanism of how the integrin secures in the bent inactivated state and sheds light on how the integrin could achieve a stable extended state.
Collapse
Affiliation(s)
- Zhenhai Li
- Shanghai Institute of Applied Mathematics and Mechanics, Shanghai Key Laboratory of Mechanics in Energy Engineering, Shanghai Frontier Science Center of Mechanoinformatics, School of Mechanics and Engineering Science, Shanghai University, Shanghai, 200072, China.
| |
Collapse
|
2
|
Héja L, Simon Á, Kardos J. Simulation of gap junction formation reveals critical role of Cys disulfide redox state in connexin hemichannel docking. Cell Commun Signal 2024; 22:185. [PMID: 38500186 PMCID: PMC10949817 DOI: 10.1186/s12964-023-01439-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Accepted: 12/12/2023] [Indexed: 03/20/2024] Open
Abstract
Video Abstract.
Collapse
Affiliation(s)
- László Héja
- Institute of Organic Chemistry, Research Centre for Natural Sciences, Magyar Tudósok Körútja 2, 1117, Budapest, Hungary.
| | - Ágnes Simon
- Institute of Organic Chemistry, Research Centre for Natural Sciences, Magyar Tudósok Körútja 2, 1117, Budapest, Hungary
| | - Julianna Kardos
- Institute of Organic Chemistry, Research Centre for Natural Sciences, Magyar Tudósok Körútja 2, 1117, Budapest, Hungary
| |
Collapse
|
3
|
Exogenous Integrin αIIbβ3 Inhibitors Revisited: Past, Present and Future Applications. Int J Mol Sci 2021; 22:ijms22073366. [PMID: 33806083 PMCID: PMC8036306 DOI: 10.3390/ijms22073366] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 03/22/2021] [Accepted: 03/23/2021] [Indexed: 12/15/2022] Open
Abstract
The integrin αIIbβ3 is the most abundant integrin on platelets. Upon platelet activation, the integrin changes its conformation (inside-out signalling) and outside-in signalling takes place leading to platelet spreading, platelet aggregation and thrombus formation. Bloodsucking parasites such as mosquitoes, leeches and ticks express anticoagulant and antiplatelet proteins, which represent major sources of lead compounds for the development of useful therapeutic agents for the treatment of haemostatic disorders or cardiovascular diseases. In addition to hematophagous parasites, snakes also possess anticoagulant and antiplatelet proteins in their salivary glands. Two snake venom proteins have been developed into two antiplatelet drugs that are currently used in the clinic. The group of proteins discussed in this review are disintegrins, low molecular weight integrin-binding cysteine-rich proteins, found in snakes, ticks, leeches, worms and horseflies. Finally, we highlight various oral antagonists, which have been tested in clinical trials but were discontinued due to an increase in mortality. No new αIIbβ3 inhibitors are developed since the approval of current platelet antagonists, and structure-function analysis of exogenous disintegrins could help find platelet antagonists with fewer adverse side effects.
Collapse
|
4
|
O'Brien HER, Zhang XF, Sanz-Hernandez M, Chion A, Shapiro S, Mobayen G, Xu Y, De Simone A, Laffan MA, McKinnon TAJ. Blocking von Willebrand factor free thiols inhibits binding to collagen under high and pathological shear stress. J Thromb Haemost 2021; 19:358-369. [PMID: 33075181 DOI: 10.1111/jth.15142] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 10/09/2020] [Accepted: 10/12/2020] [Indexed: 01/04/2023]
Abstract
BACKGROUND Von Willebrand factor (VWF) contains a number of free thiols, the majority of which are located in its C-domains, and these have been shown to alter VWF function, However, the impact of free thiols on function following acute exposure of VWF to collagen under high and pathological shear stress has not been determined. METHODS VWF free thiols were blocked with N-ethylmaleimide and flow assays performed under high and pathological shear rates to determine the impact on platelet capture and collagen binding function. Atomic force microscopy (AFM) was used to probe the interaction of VWF with collagen and molecular simulations conducted to determine the effect of free thiols on the flexibility of the VWF-C4 domain. RESULTS Blockade of VWF free thiols reduced VWF-mediated platelet capture to collagen in a shear-dependent manner, with platelet capture virtually abolished above 5000 s-1 and in regions of stenosis in microfluidic channels. Direct visualization of VWF fibers formed under extreme pathological shear rates and analysis of collagen-bound VWF attributed the effect to altered binding of VWF to collagen. AFM measurements showed that thiol-blockade reduced the lifetime and strength of the VWF-collagen bond. Pulling simulations of the VWF-C4 domain demonstrated that with one or two reduced disulphide bonds the C4 domain has increased flexibility and the propensity to undergo free-thiol exchange. CONCLUSIONS We conclude that free thiols in the C-domains of VWF enhance the flexibility of the molecule and enable it to withstand high shear forces following collagen binding, demonstrating a previously unrecognized role for VWF free thiols.
Collapse
Affiliation(s)
- Harrison E R O'Brien
- Department of Immunology and Inflammation, Centre for Haematology, Imperial College of Science Technology and Medicine, London, UK
- Institute of Structural and Molecular Biology, University College London, London, UK
| | - X Frank Zhang
- Department of Bioengineering, Department of Mechanical Engineering and Mechanics, Lehigh University, Bethlehem, PA, USA
- Department of Mechanical Engineering and Mechanics, Lehigh University, Bethlehem, PA, USA
| | | | - Alain Chion
- Irish Centre for Vascular Biology, Molecular and Cellular Therapeutics, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Susan Shapiro
- Oxford University Hospitals NHS Foundation Trust, Oxford NIHR Biomedical Research Centre, Oxford, UK
- Radcliffe Department of Medicine, Oxford University, Oxford, UK
| | - Golzar Mobayen
- Department of Immunology and Inflammation, Centre for Haematology, Imperial College of Science Technology and Medicine, London, UK
| | - Yan Xu
- Department of Bioengineering, Department of Mechanical Engineering and Mechanics, Lehigh University, Bethlehem, PA, USA
- Department of Mechanical Engineering and Mechanics, Lehigh University, Bethlehem, PA, USA
| | | | - Michael A Laffan
- Department of Immunology and Inflammation, Centre for Haematology, Imperial College of Science Technology and Medicine, London, UK
| | - Thomas A J McKinnon
- Department of Immunology and Inflammation, Centre for Haematology, Imperial College of Science Technology and Medicine, London, UK
| |
Collapse
|
5
|
Pan X, Zeng T, Zhang YH, Chen L, Feng K, Huang T, Cai YD. Investigation and Prediction of Human Interactome Based on Quantitative Features. Front Bioeng Biotechnol 2020; 8:730. [PMID: 32766217 PMCID: PMC7379396 DOI: 10.3389/fbioe.2020.00730] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Accepted: 06/09/2020] [Indexed: 01/27/2023] Open
Abstract
Protein is one of the most significant components of all living creatures. All significant and essential biological structures and functions relies on proteins and their respective biological functions. However, proteins cannot perform their unique biological significance independently. They have to interact with each other to realize the complicated biological processes in all living creatures including human beings. In other words, proteins depend on interactions (protein-protein interactions) to realize their significant effects. Thus, the significance comparison and quantitative contribution of candidate PPI features must be determined urgently. According to previous studies, 258 physical and chemical characteristics of proteins have been reported and confirmed to definitively affect the interaction efficiency of the related proteins. Among such features, essential physiochemical features of proteins like stoichiometric balance, protein abundance, molecular weight and charge distribution have been validated to be quite significant and irreplaceable for protein-protein interactions (PPIs). Therefore, in this study, we, on one hand, presented a novel computational framework to identify the key factors affecting PPIs with Boruta feature selection (BFS), Monte Carlo feature selection (MCFS), incremental feature selection (IFS), and on the other hand, built a quantitative decision-rule system to evaluate the potential PPIs under real conditions with random forest (RF) and RIPPER algorithms, thereby supplying several new insights into the detailed biological mechanisms of complicated PPIs. The main datasets and codes can be downloaded at https://github.com/xypan1232/Mass-PPI.
Collapse
Affiliation(s)
- Xiaoyong Pan
- School of Life Sciences, Shanghai University, Shanghai, China.,Key Laboratory of System Control and Information Processing, Ministry of Education of China, Institute of Image Processing and Pattern Recognition, Shanghai Jiao Tong University, Shanghai, China
| | - Tao Zeng
- Key Laboratory of Systems Biology, Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, Shanghai, China
| | - Yu-Hang Zhang
- Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Lei Chen
- College of Information Engineering, Shanghai Maritime University, Shanghai, China
| | - Kaiyan Feng
- Department of Computer Science, Guangdong AIB Polytechnic, Guangzhou, China
| | - Tao Huang
- Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Yu-Dong Cai
- School of Life Sciences, Shanghai University, Shanghai, China
| |
Collapse
|
6
|
Bergerhausen L, Grosche J, Meißner J, Hecker C, Caliandro MF, Westerhausen C, Kamenac A, Rezaei M, Mörgelin M, Poschmann G, Vestweber D, Hanschmann EM, Eble JA. Extracellular Redox Regulation of α7β Integrin-Mediated Cell Migration Is Signaled via a Dominant Thiol-Switch. Antioxidants (Basel) 2020; 9:antiox9030227. [PMID: 32164274 PMCID: PMC7139957 DOI: 10.3390/antiox9030227] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 03/06/2020] [Accepted: 03/08/2020] [Indexed: 12/21/2022] Open
Abstract
While adhering to extracellular matrix (ECM) proteins, such as laminin-111, cells temporarily produce hydrogen peroxide at adhesion sites. To study the redox regulation of α7β1 integrin-mediated cell adhesion to laminin-111, a conserved cysteine pair within the α-subunit hinge region was replaced for alanines. The molecular and cellular effects were analyzed by electron and atomic force microscopy, impedance-based migration assays, flow cytometry and live cell imaging. This cysteine pair constitutes a thiol-switch, which redox-dependently governs the equilibrium between an extended and a bent integrin conformation with high and low ligand binding activity, respectively. Hydrogen peroxide oxidizes the cysteines to a disulfide bond, increases ligand binding and promotes cell migration toward laminin-111. Inversely, extracellular thioredoxin-1 reduces the disulfide, thereby decreasing laminin binding. Mutation of this cysteine pair into the non-oxidizable hinge-mutant shows molecular and cellular effects similar to the reduced wild-type integrin, but lacks redox regulation. This proves the existence of a dominant thiol-switch within the α subunit hinge of α7β1 integrin, which is sufficient to implement activity regulation by extracellular redox agents in a redox-regulatory circuit. Our data reveal a novel and physiologically relevant thiol-based regulatory mechanism of integrin-mediated cell-ECM interactions, which employs short-lived hydrogen peroxide and extracellular thioredoxin-1 as signaling mediators.
Collapse
Affiliation(s)
- Lukas Bergerhausen
- Institute of Physiological Chemistry and Pathobiochemistry, University of Münster, 48149 Münster, Germany; (L.B.); (J.G.); (J.M.); (M.F.C.); (M.R.)
| | - Julius Grosche
- Institute of Physiological Chemistry and Pathobiochemistry, University of Münster, 48149 Münster, Germany; (L.B.); (J.G.); (J.M.); (M.F.C.); (M.R.)
| | - Juliane Meißner
- Institute of Physiological Chemistry and Pathobiochemistry, University of Münster, 48149 Münster, Germany; (L.B.); (J.G.); (J.M.); (M.F.C.); (M.R.)
| | - Christina Hecker
- Department of Neurology, Medical Faculty, Heinrich-Heine University Düsseldorf, 40225 Düsseldorf, Germany; (C.H.); (E.-M.H.)
| | - Michele F. Caliandro
- Institute of Physiological Chemistry and Pathobiochemistry, University of Münster, 48149 Münster, Germany; (L.B.); (J.G.); (J.M.); (M.F.C.); (M.R.)
| | - Christoph Westerhausen
- Biophysics Group, Department of Experimental Physics, Institute of Physics, University of Augsburg, 86159 Augsburg, Germany (A.K.)
- Institute of Theoretical Medicine, University of Augsburg, 86159 Augsburg, Germany
| | - Andrej Kamenac
- Biophysics Group, Department of Experimental Physics, Institute of Physics, University of Augsburg, 86159 Augsburg, Germany (A.K.)
| | - Maryam Rezaei
- Institute of Physiological Chemistry and Pathobiochemistry, University of Münster, 48149 Münster, Germany; (L.B.); (J.G.); (J.M.); (M.F.C.); (M.R.)
| | | | - Gereon Poschmann
- Institute of Molecular Medicine I, Functional Redox Proteomics, Heinrich-Heine University Düsseldorf, 40225 Düsseldorf, Germany;
| | - Dietmar Vestweber
- Department of Vascular Cell Biology, Max Planck-Institute of Molecular Biomedicine, 48149 Münster, Germany;
| | - Eva-Maria Hanschmann
- Department of Neurology, Medical Faculty, Heinrich-Heine University Düsseldorf, 40225 Düsseldorf, Germany; (C.H.); (E.-M.H.)
| | - Johannes A. Eble
- Institute of Physiological Chemistry and Pathobiochemistry, University of Münster, 48149 Münster, Germany; (L.B.); (J.G.); (J.M.); (M.F.C.); (M.R.)
- Correspondence: ; Tel.: +49-251-835-5591
| |
Collapse
|
7
|
Le Blanc J, Lordkipanidzé M. Platelet Function in Aging. Front Cardiovasc Med 2019; 6:109. [PMID: 31448291 PMCID: PMC6692461 DOI: 10.3389/fcvm.2019.00109] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 07/22/2019] [Indexed: 12/20/2022] Open
Abstract
Aging is associated with an increased incidence of cardiovascular disease and thrombosis. Platelets play a major role in maintaining hemostasis and in thrombus formation, making them a key player in thrombotic disorders. Whereas it is well-known that platelet aggregability is increased in vascular diseases, the contribution of age-related changes in platelet biology to cardiovascular risk is not well-understood. Several lines of evidence support that platelets from older subjects differ in their function and structure, making platelets more prone to activation and less sensitive to inhibition. These age-related changes could lead to platelet hyperactivity and to the development of a prothrombotic state in advanced age. This review will focus on platelet biochemical modifications during aging and on the mechanisms by which these alterations could lead to thrombotic disease.
Collapse
Affiliation(s)
- Jessica Le Blanc
- Research Center, Montreal Heart Institute, Montreal, QC, Canada.,Faculty of Pharmacy, Université de Montréal, Montreal, QC, Canada
| | - Marie Lordkipanidzé
- Research Center, Montreal Heart Institute, Montreal, QC, Canada.,Faculty of Pharmacy, Université de Montréal, Montreal, QC, Canada
| |
Collapse
|
8
|
Accessibility explains preferred thiol-disulfide isomerization in a protein domain. Sci Rep 2017; 7:9858. [PMID: 28851879 PMCID: PMC5575259 DOI: 10.1038/s41598-017-07501-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Accepted: 06/29/2017] [Indexed: 11/17/2022] Open
Abstract
Disulfide bonds are key stabilizing and yet potentially labile cross-links in proteins. While spontaneous disulfide rearrangement through thiol-disulfide exchange is increasingly recognized to play an important physiological role, its molecular determinants are still largely unknown. Here, we used a novel hybrid Monte Carlo and Molecular Dynamics scheme to elucidate the molecular principles of thiol-disulfide exchange in proteins, for a mutated immunoglobulin domain as a model system. Unexpectedly, using simple proximity as the criterion for thiol-disulfide exchange, our method correctly predicts the experimentally observed regiospecificity and selectivity of the cysteine-rich protein. While redox reactivity has been examined primarily on the level of transition states and activation barriers, our results argue for accessibility of the disulfide by the attacking thiol given the highly dynamic and sterically demanding protein as a major bottleneck of thiol-disulfide exchange. This scenario may be similarly at play in other proteins with or without an evolutionarily designed active site.
Collapse
|
9
|
Neves RPP, Fernandes PA, Varandas AJC, Ramos MJ. Benchmarking of Density Functionals for the Accurate Description of Thiol-Disulfide Exchange. J Chem Theory Comput 2015; 10:4842-56. [PMID: 26584371 DOI: 10.1021/ct500840f] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A set of 92 density functionals was employed to accurately characterize thiol-disulfide exchange. The properties we have benchmarked throughout the study include the geometry of a 15 atoms model system, the potential energy surface, the activation barrier, and the energy of reaction for thiol-disulfide exchange. Reference energies were determined at the CCSD(T)/CBS//MP2/aug-cc-pVDZ level of theory, and reference geometries were calculated at the MP2/aug-cc-pVTZ level. M11-L, M06-2X, M06-HF, N12-SX, PBE1PBE, PBEh1PBE, and OHSE2PBE described better the geometry of the model system, with average deviations of 0.06 Å in bond lengths (0.06 Å in bond-breaking lengths) and 1.9° in bond angles. On the other hand, the potential energy surface and its gradient were more accurately described by the hybrid density functional BHandH, closely followed by mPW1N, mPW1K, and mPWB1K. The barrier height and energy of reaction were better reproduced by the BMK and M06-2X functionals (deviations of 0.17 and 0.07 kcal·mol(-1), respectively) for a set of 10 Pople's basis sets. MN12-SX and M11-L showed very good results for the widely used 6-311++G(2d,2p) basis set, with deviations of 0.02 and 0.05 kcal·mol(-1), respectively. We studied the effect of the split-valence, diffuse, and polarized functions in the activation barrier of thiol-disulfide exchange, for a set of 10 Pople's basis sets. While increasing the splitting and polarization may increase the activation barrier in approximately 1 kcal·mol(-1), diffuse functions generally contribute to decreasing it no more than 0.10 kcal·mol(-1). In general, 13 functionals provided energies within 1 kcal·mol(-1) of the reference value. The BB1K density functional is one of the best density functionals to characterize thiol-disulfide exchange reactions; however, several density functionals with modified Perdew-Wang exchange and about 40% Hartree-Fock exchange, such as mPW1K, mPW1N, and mPWB1K, show a good performance, too.
Collapse
Affiliation(s)
- Rui P P Neves
- REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto , Rua do Campo Alegre, s/n, 4169-007 Porto, Portugal
| | - Pedro A Fernandes
- REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto , Rua do Campo Alegre, s/n, 4169-007 Porto, Portugal
| | - António J C Varandas
- Departamento de Química, and Centro de Química, Universidade de Coimbra , 3004-535 Coimbra, Portugal
| | - Maria J Ramos
- REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade do Porto , Rua do Campo Alegre, s/n, 4169-007 Porto, Portugal
| |
Collapse
|
10
|
Lazzarin M, Cozzi R, Malito E, Martinelli M, D'Onofrio M, Maione D, Margarit I, Rinaudo CD. Noncanonical sortase‐mediated assembly of pilus type 2b in group B
Streptococcus. FASEB J 2015. [DOI: 10.1096/fj.15-272500] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | - Roberta Cozzi
- Novartis Vaccines and Diagnostics, GlaxoSmithKlineSienaItaly
| | - Enrico Malito
- Novartis Vaccines and Diagnostics, GlaxoSmithKlineSienaItaly
| | | | - Mariapina D'Onofrio
- Nuclear Magnetic Resonance LaboratoryDepartment of BiotechnologyUniversity of VeronaVeronaItaly
| | - Domenico Maione
- Novartis Vaccines and Diagnostics, GlaxoSmithKlineSienaItaly
| | | | | |
Collapse
|
11
|
Buitrago L, Rendon A, Liang Y, Simeoni I, Negri A, Filizola M, Ouwehand WH, Coller BS. αIIbβ3 variants defined by next-generation sequencing: predicting variants likely to cause Glanzmann thrombasthenia. Proc Natl Acad Sci U S A 2015; 112:E1898-907. [PMID: 25827233 PMCID: PMC4403182 DOI: 10.1073/pnas.1422238112] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Next-generation sequencing is transforming our understanding of human genetic variation but assessing the functional impact of novel variants presents challenges. We analyzed missense variants in the integrin αIIbβ3 receptor subunit genes ITGA2B and ITGB3 identified by whole-exome or -genome sequencing in the ThromboGenomics project, comprising ∼32,000 alleles from 16,108 individuals. We analyzed the results in comparison with 111 missense variants in these genes previously reported as being associated with Glanzmann thrombasthenia (GT), 20 associated with alloimmune thrombocytopenia, and 5 associated with aniso/macrothrombocytopenia. We identified 114 novel missense variants in ITGA2B (affecting ∼11% of the amino acids) and 68 novel missense variants in ITGB3 (affecting ∼9% of the amino acids). Of the variants, 96% had minor allele frequencies (MAF) < 0.1%, indicating their rarity. Based on sequence conservation, MAF, and location on a complete model of αIIbβ3, we selected three novel variants that affect amino acids previously associated with GT for expression in HEK293 cells. αIIb P176H and β3 C547G severely reduced αIIbβ3 expression, whereas αIIb P943A partially reduced αIIbβ3 expression and had no effect on fibrinogen binding. We used receiver operating characteristic curves of combined annotation-dependent depletion, Polyphen 2-HDIV, and sorting intolerant from tolerant to estimate the percentage of novel variants likely to be deleterious. At optimal cut-off values, which had 69-98% sensitivity in detecting GT mutations, between 27% and 71% of the novel αIIb or β3 missense variants were predicted to be deleterious. Our data have implications for understanding the evolutionary pressure on αIIbβ3 and highlight the challenges in predicting the clinical significance of novel missense variants.
Collapse
Affiliation(s)
- Lorena Buitrago
- Allen and Frances Adler Laboratory of Blood and Vascular Biology and
| | - Augusto Rendon
- Department of Haematology, University of Cambridge, Cambridge CB2 0PT, United Kingdom; Medical Research Council Biostatistics Unit, Cambridge Biomedical Campus, Cambridge Institute of Public Health, Cambridge, United Kingdom; National Health Service Blood & Transplant, Cambridge, United Kingdom
| | - Yupu Liang
- Research Bioinformatics, The Rockefeller University, New York, NY 10065
| | - Ilenia Simeoni
- Department of Haematology, University of Cambridge, Cambridge CB2 0PT, United Kingdom; National Health Service Blood & Transplant, Cambridge, United Kingdom
| | - Ana Negri
- Department of Structural and Chemical Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029; and
| | - Marta Filizola
- Department of Structural and Chemical Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029; and
| | - Willem H Ouwehand
- Department of Haematology, University of Cambridge, Cambridge CB2 0PT, United Kingdom; National Health Service Blood & Transplant, Cambridge, United Kingdom; Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Barry S Coller
- Allen and Frances Adler Laboratory of Blood and Vascular Biology and
| |
Collapse
|
12
|
Chen IH, Chang FR, Wu YC, Kung PH, Wu CC. 3,4-Methylenedioxy-β-nitrostyrene inhibits adhesion and migration of human triple-negative breast cancer cells by suppressing β1 integrin function and surface protein disulfide isomerase. Biochimie 2015; 110:81-92. [PMID: 25593085 DOI: 10.1016/j.biochi.2015.01.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Accepted: 01/05/2015] [Indexed: 11/17/2022]
Abstract
Triple negative breast cancer (TNBC) exhibits an aggressive clinical course by high metastatic potential. It is known that integrin-mediated cell adhesion and migration are important for cancer metastasis. In the present study, a synthetic compound, 3, 4-methyenedioxy-β-nitrostyrene (MNS), significantly inhibited adhesion of TNBC cell lines to different extracellular matrix (ECM) components. The antimetastatic capacity of MNS was also observed through reducing TNBC cells migration and invasion without affecting cell viability. Confocal microscopy revealed that MNS disrupted the formation of focal adhesion complex and actin stress fiber networks. Consistent with this finding, MNS inhibited phosphorylation of focal adhesion kinase (FAK) and paxillin as detected by Western blot analysis. In exploring the underlying mechanism, we found that MNS inhibited phosphorylation of FAK as a result of reducing β1 integrin activation and clustering. A cell-impermeable dithiol reagent, 2, 3-dimercaptopropane-1-sulfonic acid abrogated all of MNS's actions, indicating that MNS may react with thiol groups of cell surface proteins that are involved in regulation of β1 integrin function as well as cell adhesion and migration. Cell surface protein disulfide isomerase (PDI) has been reported to be essential for the affinity modulation of β integrins. We also demonstrated that MNS inhibited PDI activity both in a pure enzyme system and in intact cancer cells. Taken together, our results suggest that MNS inhibits in vitro metastatic properties of TNBC cells through suppression of β1 integrin activation and focal adhesion signaling. Moreover, inhibition of surface PDI may contribute, at least in part, to the actions of MNS. These results suggest that MNS has a potential to be developed as an anticancer agent for treatment of TNBC.
Collapse
Affiliation(s)
- I-Hua Chen
- Graduate Institute of Natural Products, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Fang-Rong Chang
- Graduate Institute of Natural Products, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Yang-Chang Wu
- School of Pharmacy, College of Pharmacy, China Medical University, Taichung, Taiwan.
| | - Po-Hsiung Kung
- Graduate Institute of Natural Products, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Chin-Chung Wu
- Graduate Institute of Natural Products, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Marine Biotechnology and Resources, National Sun Yat-Sen University, Kaohsiung, Taiwan.
| |
Collapse
|