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Müller-Renno C, Ziegler C. The Contribution of Scanning Force Microscopy on Dental Research: A Narrative Review. MATERIALS (BASEL, SWITZERLAND) 2024; 17:2100. [PMID: 38730904 PMCID: PMC11084532 DOI: 10.3390/ma17092100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 04/23/2024] [Accepted: 04/24/2024] [Indexed: 05/13/2024]
Abstract
Scanning force microscopy (SFM) is one of the most widely used techniques in biomaterials research. In addition to imaging the materials of interest, SFM enables the mapping of mechanical properties and biological responses with sub-nanometer resolution and piconewton sensitivity. This review aims to give an overview of using the scanning force microscope (SFM) for investigations on dental materials. In particular, SFM-derived methods such as force-distance curves (scanning force spectroscopy), lateral force spectroscopy, and applications of the FluidFM® will be presented. In addition to the properties of dental materials, this paper reports the development of the pellicle by the interaction of biopolymers such as proteins and polysaccharides, as well as the interaction of bacteria with dental materials.
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Affiliation(s)
- Christine Müller-Renno
- Department of Physics and Research Center OPTIMAS, RPTU Kaiserslautern, 67663 Kaiserslautern, Germany;
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2
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Steinert L, Fuchs M, Sigmund AM, Didona D, Hudemann C, Möbs C, Hertl M, Hashimoto T, Waschke J, Vielmuth F. Desmosomal Hyper-adhesion Affects Direct Inhibition of Desmoglein Interactions in Pemphigus. J Invest Dermatol 2024:S0022-202X(24)00308-7. [PMID: 38677661 DOI: 10.1016/j.jid.2024.03.042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 02/06/2024] [Accepted: 03/02/2024] [Indexed: 04/29/2024]
Abstract
During differentiation, keratinocytes acquire a strong, hyper-adhesive state, where desmosomal cadherins interact calcium ion independently. Previous data indicate that hyper-adhesion protects keratinocytes from pemphigus vulgaris autoantibody-induced loss of intercellular adhesion, although the underlying mechanism remains to be elucidated. Thus, in this study, we investigated the effect of hyper-adhesion on pemphigus vulgaris autoantibody-induced direct inhibition of desmoglein (DSG) 3 interactions by atomic force microscopy. Hyper-adhesion abolished loss of intercellular adhesion and corresponding morphological changes of all pathogenic antibodies used. Pemphigus autoantibodies putatively targeting several parts of the DSG3 extracellular domain and 2G4, targeting a membrane-proximal domain of DSG3, induced direct inhibition of DSG3 interactions only in non-hyper-adhesive keratinocytes. In contrast, AK23, targeting the N-terminal extracellular domain 1 of DSG3, caused direct inhibition under both adhesive states. However, antibody binding to desmosomal cadherins was not different between the distinct pathogenic antibodies used and was not changed during acquisition of hyper-adhesion. In addition, heterophilic DSC3-DSG3 and DSG2-DSG3 interactions did not cause reduced susceptibility to direct inhibition under hyper-adhesive condition in wild-type keratinocytes. Taken together, the data suggest that hyper-adhesion reduces susceptibility to autoantibody-induced direct inhibition in dependency on autoantibody-targeted extracellular domain but also demonstrate that further mechanisms are required for the protective effect of desmosomal hyper-adhesion in pemphigus vulgaris.
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Affiliation(s)
- Letyfee Steinert
- Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, Ludwig Maximilian University of Munich, Munich, Germany
| | - Michael Fuchs
- Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, Ludwig Maximilian University of Munich, Munich, Germany
| | - Anna M Sigmund
- Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, Ludwig Maximilian University of Munich, Munich, Germany
| | - Dario Didona
- Department of Dermatology and Allergology, Philipps-Universität Marburg, Marburg, Germany
| | - Christoph Hudemann
- Department of Dermatology and Allergology, Philipps-Universität Marburg, Marburg, Germany
| | - Christian Möbs
- Department of Dermatology and Allergology, Philipps-Universität Marburg, Marburg, Germany
| | - Michael Hertl
- Department of Dermatology and Allergology, Philipps-Universität Marburg, Marburg, Germany
| | - Takashi Hashimoto
- Department of Dermatology, Graduate School of Medicine, Osaka City Metropolitan University, Osaka, Japan
| | - Jens Waschke
- Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, Ludwig Maximilian University of Munich, Munich, Germany
| | - Franziska Vielmuth
- Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, Ludwig Maximilian University of Munich, Munich, Germany.
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3
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Zemła J, Szydlak R, Gajos K, Kozłowski Ł, Zieliński T, Luty M, Øvreeide IH, Prot VE, Stokke BT, Lekka M. Plasma Treatment of PDMS for Microcontact Printing (μCP) of Lectins Decreases Silicone Transfer and Increases the Adhesion of Bladder Cancer Cells. ACS APPLIED MATERIALS & INTERFACES 2023; 15:51863-51875. [PMID: 37889219 PMCID: PMC10636731 DOI: 10.1021/acsami.3c09195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 10/10/2023] [Accepted: 10/10/2023] [Indexed: 10/28/2023]
Abstract
The present study investigates silicone transfer occurring during microcontact printing (μCP) of lectins with polydimethylsiloxane (PDMS) stamps and its impact on the adhesion of cells. Static adhesion assays and single-cell force spectroscopy (SCFS) are used to compare adhesion of nonmalignant (HCV29) and cancer (HT1376) bladder cells, respectively, to high-affinity lectin layers (PHA-L and WGA, respectively) prepared by physical adsorption and μCP. The chemical composition of the μCP lectin patterns was monitored by time-of-flight secondary ion mass spectrometry (ToF-SIMS). We show that the amount of transferred silicone in the μCP process depends on the preprocessing of the PDMS stamps. It is revealed that silicone contamination within the patterned lectin layers inhibits the adhesion of bladder cells, and the work of adhesion is lower for μCP lectins than for drop-cast lectins. The binding capacity of microcontact printed lectins was larger when the PDMS stamps were treated with UV ozone plasma as compared to sonication in ethanol and deionized water. ToF-SIMS data show that ozone-based treatment of PDMS stamps used for μCP of lectin reduces the silicone contamination in the imprinting protocol regardless of stamp geometry (flat vs microstructured). The role of other possible contributors, such as the lectin conformation and organization of lectin layers, is also discussed.
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Affiliation(s)
- Joanna Zemła
- Institute
of Nuclear Physics, Polish Academy of Sciences, PL-31342 Krakow, Poland
| | - Renata Szydlak
- Institute
of Nuclear Physics, Polish Academy of Sciences, PL-31342 Krakow, Poland
| | - Katarzyna Gajos
- M.
Smoluchowski Institute of Physics, Jagiellonian
University, 30348 Kraków, Poland
| | - Łukasz Kozłowski
- Institute
of Nuclear Physics, Polish Academy of Sciences, PL-31342 Krakow, Poland
| | - Tomasz Zieliński
- Institute
of Nuclear Physics, Polish Academy of Sciences, PL-31342 Krakow, Poland
| | - Marcin Luty
- Institute
of Nuclear Physics, Polish Academy of Sciences, PL-31342 Krakow, Poland
| | - Ingrid H. Øvreeide
- Biophysics
and Medical Technology, Department of Physics, The Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway
| | - Victorien E. Prot
- Biomechanics,
Department of Structural Engineering, The
Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway
| | - Bjørn T. Stokke
- Biophysics
and Medical Technology, Department of Physics, The Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway
| | - Małgorzata Lekka
- Institute
of Nuclear Physics, Polish Academy of Sciences, PL-31342 Krakow, Poland
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4
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Fernandez M, Shkumatov AV, Liu Y, Stulemeijer C, Derclaye S, Efremov R, Hallet B, Alsteens D. AFM-based force spectroscopy unravels stepwise formation of the DNA transposition complex in the widespread Tn3 family mobile genetic elements. Nucleic Acids Res 2023; 51:4929-4941. [PMID: 37026471 PMCID: PMC10250215 DOI: 10.1093/nar/gkad241] [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: 12/21/2022] [Revised: 03/03/2023] [Accepted: 03/23/2023] [Indexed: 04/08/2023] Open
Abstract
Transposon Tn4430 belongs to a widespread family of bacterial transposons, the Tn3 family, which plays a prevalent role in the dissemination of antibiotic resistance among pathogens. Despite recent data on the structural architecture of the transposition complex, the molecular mechanisms underlying the replicative transposition of these elements are still poorly understood. Here, we use force-distance curve-based atomic force microscopy to probe the binding of the TnpA transposase of Tn4430 to DNA molecules containing one or two transposon ends and to extract the thermodynamic and kinetic parameters of transposition complex assembly. Comparing wild-type TnpA with previously isolated deregulated TnpA mutants supports a stepwise pathway for transposition complex formation and activation during which TnpA first binds as a dimer to a single transposon end and then undergoes a structural transition that enables it to bind the second end cooperatively and to become activated for transposition catalysis, the latter step occurring at a much faster rate for the TnpA mutants. Our study thus provides an unprecedented approach to probe the dynamic of a complex DNA processing machinery at the single-particle level.
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Affiliation(s)
- Maricruz Fernandez
- NanoBioPhysics lab, Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
- Biochemistry and Genetics of Microorganisms, Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Alexander V Shkumatov
- Center for Structural Biology, Vlaams Instituut voor Biotechnologie, Brussels, Belgium
- Structural Biology Brussels, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Yun Liu
- Center for Structural Biology, Vlaams Instituut voor Biotechnologie, Brussels, Belgium
- Structural Biology Brussels, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Claire Stulemeijer
- Biochemistry and Genetics of Microorganisms, Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Sylvie Derclaye
- NanoBioPhysics lab, Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Rouslan G Efremov
- Center for Structural Biology, Vlaams Instituut voor Biotechnologie, Brussels, Belgium
- Structural Biology Brussels, Department of Bioengineering Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Bernard Hallet
- Biochemistry and Genetics of Microorganisms, Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - David Alsteens
- NanoBioPhysics lab, Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-la-Neuve, Belgium
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5
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Pan Y, Pohjolainen E, Schmidpeter PAM, Vaiana AC, Nimigean CM, Grubmüller H, Scheuring S. Discrimination between cyclic nucleotides in a cyclic nucleotide-gated ion channel. Nat Struct Mol Biol 2023; 30:512-520. [PMID: 36973509 DOI: 10.1038/s41594-023-00955-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Accepted: 02/24/2023] [Indexed: 03/29/2023]
Abstract
Cyclic nucleotide-gated ion channels are crucial in many physiological processes such as vision and pacemaking in the heart. SthK is a prokaryotic homolog with high sequence and structure similarities to hyperpolarization-activated and cyclic nucleotide-modulated and cyclic nucleotide-gated channels, especially at the level of the cyclic nucleotide binding domains (CNBDs). Functional measurements showed that cyclic adenosine monophosphate (cAMP) is a channel activator while cyclic guanosine monophosphate (cGMP) barely leads to pore opening. Here, using atomic force microscopy single-molecule force spectroscopy and force probe molecular dynamics simulations, we unravel quantitatively and at the atomic level how CNBDs discriminate between cyclic nucleotides. We find that cAMP binds to the SthK CNBD slightly stronger than cGMP and accesses a deep-bound state that a cGMP-bound CNBD cannot reach. We propose that the deep binding of cAMP is the discriminatory state that is essential for cAMP-dependent channel activation.
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Affiliation(s)
- Yangang Pan
- Department of Anesthesiology, Weill Cornell Medicine, New York, NY, USA
| | - Emmi Pohjolainen
- Max Planck Institute for Multidisciplinary Sciences, Theoretical and Computational Biophysics Department, Goettingen, Germany
| | | | - Andrea C Vaiana
- Max Planck Institute for Multidisciplinary Sciences, Theoretical and Computational Biophysics Department, Goettingen, Germany
- Institute of Biophysics, National Research Council, Palermo, Italy
| | - Crina M Nimigean
- Department of Anesthesiology, Weill Cornell Medicine, New York, NY, USA
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY, USA
| | - Helmut Grubmüller
- Max Planck Institute for Multidisciplinary Sciences, Theoretical and Computational Biophysics Department, Goettingen, Germany
| | - Simon Scheuring
- Department of Anesthesiology, Weill Cornell Medicine, New York, NY, USA.
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY, USA.
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6
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Shoykhet M, Dervishi O, Menauer P, Hiermaier M, Moztarzadeh S, Osterloh C, Ludwig RJ, Williams T, Gerull B, Kääb S, Clauss S, Schüttler D, Waschke J, Yeruva S. EGFR inhibition leads to enhanced desmosome assembly and cardiomyocyte cohesion via ROCK activation. JCI Insight 2023; 8:163763. [PMID: 36795511 PMCID: PMC10070108 DOI: 10.1172/jci.insight.163763] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Accepted: 02/15/2023] [Indexed: 02/17/2023] Open
Abstract
Arrhythmogenic cardiomyopathy (AC) is a familial heart disease partly caused by impaired desmosome turnover. Thus, stabilization of desmosome integrity may provide new treatment options. Desmosomes, apart from cellular cohesion, provide the structural framework of a signaling hub. Here, we investigated the role of the epidermal growth factor receptor (EGFR) in cardiomyocyte cohesion. We inhibited EGFR under physiological and pathophysiological conditions using the murine plakoglobin-KO AC model, in which EGFR was upregulated. EGFR inhibition enhanced cardiomyocyte cohesion. Immunoprecipitation showed an interaction of EGFR and desmoglein 2 (DSG2). Immunostaining and atomic force microscopy (AFM) revealed enhanced DSG2 localization and binding at cell borders upon EGFR inhibition. Enhanced area composita length and desmosome assembly were observed upon EGFR inhibition, confirmed by enhanced DSG2 and desmoplakin (DP) recruitment to cell borders. PamGene Kinase assay performed in HL-1 cardiomyocytes treated with erlotinib, an EGFR inhibitor, revealed upregulation of Rho-associated protein kinase (ROCK). Erlotinib-mediated desmosome assembly and cardiomyocyte cohesion were abolished upon ROCK inhibition. Thus, inhibiting EGFR and, thereby, stabilizing desmosome integrity via ROCK might provide treatment options for AC.
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Affiliation(s)
- Maria Shoykhet
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, Ludwig Maximilian University (LMU), Munich, Germany
| | - Orsela Dervishi
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, Ludwig Maximilian University (LMU), Munich, Germany
| | - Philipp Menauer
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, Ludwig Maximilian University (LMU), Munich, Germany
| | - Matthias Hiermaier
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, Ludwig Maximilian University (LMU), Munich, Germany
| | - Sina Moztarzadeh
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, Ludwig Maximilian University (LMU), Munich, Germany
| | - Colin Osterloh
- Lübeck Institute of Experimental Dermatology and Center for Research on Inflammation of the Skin, University of Lübeck, Lübeck, Germany
| | - Ralf J Ludwig
- Lübeck Institute of Experimental Dermatology and Center for Research on Inflammation of the Skin, University of Lübeck, Lübeck, Germany
| | - Tatjana Williams
- Comprehensive Heart Failure Center and Department of Medicine I, University Hospital Würzburg, Würzburg, Germany
| | - Brenda Gerull
- Comprehensive Heart Failure Center and Department of Medicine I, University Hospital Würzburg, Würzburg, Germany
| | - Stefan Kääb
- Medizinische Klinik und Poliklinik I, LMU Hospital, LMU, Munich, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Munich, Munich Heart Alliance (MHA), Munich, Germany
- Interfaculty Center for Endocrine and Cardiovascular Disease Network Modeling and Clinical Transfer (ICONLMU), LMU Munich, Munich, Germany
| | - Sebastian Clauss
- Medizinische Klinik und Poliklinik I, LMU Hospital, LMU, Munich, Germany
- DZHK (German Centre for Cardiovascular Research), Partner Site Munich, Munich Heart Alliance (MHA), Munich, Germany
- Interfaculty Center for Endocrine and Cardiovascular Disease Network Modeling and Clinical Transfer (ICONLMU), LMU Munich, Munich, Germany
- Institute of Surgical Research at the Walter-Brendel-Centre of Experimental Medicine, LMU Hospital, LMU, Munich, Germany
| | - Dominik Schüttler
- Medizinische Klinik und Poliklinik I, LMU Hospital, LMU, Munich, Germany
- Interfaculty Center for Endocrine and Cardiovascular Disease Network Modeling and Clinical Transfer (ICONLMU), LMU Munich, Munich, Germany
- Institute of Surgical Research at the Walter-Brendel-Centre of Experimental Medicine, LMU Hospital, LMU, Munich, Germany
| | - Jens Waschke
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, Ludwig Maximilian University (LMU), Munich, Germany
| | - Sunil Yeruva
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, Ludwig Maximilian University (LMU), Munich, Germany
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Apremilast prevents blistering in human epidermis and stabilizes keratinocyte adhesion in pemphigus. Nat Commun 2023; 14:116. [PMID: 36624106 PMCID: PMC9829900 DOI: 10.1038/s41467-022-35741-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 12/21/2022] [Indexed: 01/10/2023] Open
Abstract
Pemphigus vulgaris is a life-threatening blistering skin disease caused by autoantibodies destabilizing desmosomal adhesion. Current therapies focus on suppression of autoantibody formation and thus treatments directly stabilizing keratinocyte adhesion would fulfill an unmet medical need. We here demonstrate that apremilast, a phosphodiesterase 4 inhibitor used in psoriasis, prevents skin blistering in pemphigus vulgaris. Apremilast abrogates pemphigus autoantibody-induced loss of keratinocyte cohesion in ex-vivo human epidermis, cultured keratinocytes in vitro and in vivo in mice. In parallel, apremilast inhibits keratin retraction as well as desmosome splitting, induces phosphorylation of plakoglobin at serine 665 and desmoplakin assembly into desmosomal plaques. We established a plakoglobin phospho-deficient mouse model that reveals fragile epidermis with altered organization of keratin filaments and desmosomal cadherins. In keratinocytes derived from these mice, intercellular adhesion is impaired and not rescued by apremilast. These data identify an unreported mechanism of desmosome regulation and propose that apremilast stabilizes keratinocyte adhesion and is protective in pemphigus.
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Identification of the Actin-Binding Region and Binding to Host Plant Apple Actin of Immunodominant Transmembrane Protein of ' Candidatus Phytoplasma mali'. Int J Mol Sci 2023; 24:ijms24020968. [PMID: 36674483 PMCID: PMC9860668 DOI: 10.3390/ijms24020968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 12/21/2022] [Accepted: 12/28/2022] [Indexed: 01/07/2023] Open
Abstract
'Candidatus Phytoplasma mali' ('Ca. P. mali') has only one major membrane protein, the immunodominant membrane protein (Imp), which is regarded as being close to the ancestor of all phytoplasma immunodominant membrane proteins. Imp binds to actin and possibly facilitates its movement in the plant or insect host cells. However, protein sequences of Imp are quite diverse among phytoplasma species, thus resulting in difficulties in identifying conserved domains across species. In this work, we compare Imp protein sequences of 'Ca. P. mali' strain PM19 (Imp-PM19) with Imp of different strains of 'Ca. P. mali' and identify its actin-binding domain. Moreover, we show that Imp binds to the actin of apple (Malus x domestica), which is the host plant of 'Ca. P. mali'. Using molecular and scanning force spectroscopy analysis, we find that the actin-binding domain of Imp-PM19 contains a highly positively charged amino acid cluster. Our result could allow investigating a possible correlation between Imp variants and the infectivity of the corresponding 'Ca. P. mali' isolates.
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Schinner C, Xu L, Franz H, Zimmermann A, Wanuske MT, Rathod M, Hanns P, Geier F, Pelczar P, Liang Y, Lorenz V, Stüdle C, Maly PI, Kauferstein S, Beckmann BM, Sheikh F, Kuster GM, Spindler V. Defective Desmosomal Adhesion Causes Arrhythmogenic Cardiomyopathy by Involving an Integrin-αVβ6/TGF-β Signaling Cascade. Circulation 2022; 146:1610-1626. [PMID: 36268721 PMCID: PMC9674449 DOI: 10.1161/circulationaha.121.057329] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
BACKGROUND Arrhythmogenic cardiomyopathy (ACM) is characterized by progressive loss of cardiomyocytes with fibrofatty tissue replacement, systolic dysfunction, and life-threatening arrhythmias. A substantial proportion of ACM is caused by mutations in genes of the desmosomal cell-cell adhesion complex, but the underlying mechanisms are not well understood. In the current study, we investigated the relevance of defective desmosomal adhesion for ACM development and progression. METHODS We mutated the binding site of DSG2 (desmoglein-2), a crucial desmosomal adhesion molecule in cardiomyocytes. This DSG2-W2A mutation abrogates the tryptophan swap, a central interaction mechanism of DSG2 on the basis of structural data. Impaired adhesive function of DSG2-W2A was confirmed by cell-cell dissociation assays and force spectroscopy measurements by atomic force microscopy. The DSG2-W2A knock-in mouse model was analyzed by echocardiography, ECG, and histologic and biomolecular techniques including RNA sequencing and transmission electron and superresolution microscopy. The results were compared with ACM patient samples, and their relevance was confirmed in vivo and in cardiac slice cultures by inhibitor studies applying the small molecule EMD527040 or an inhibitory integrin-αVβ6 antibody. RESULTS The DSG2-W2A mutation impaired binding on molecular level and compromised intercellular adhesive function. Mice bearing this mutation develop a severe cardiac phenotype recalling the characteristics of ACM, including cardiac fibrosis, impaired systolic function, and arrhythmia. A comparison of the transcriptome of mutant mice with ACM patient data suggested deregulated integrin-αVβ6 and subsequent transforming growth factor-β signaling as driver of cardiac fibrosis. Blocking integrin-αVβ6 led to reduced expression of profibrotic markers and reduced fibrosis formation in mutant animals in vivo. CONCLUSIONS We show that disruption of desmosomal adhesion is sufficient to induce a phenotype that fulfils the clinical criteria to establish the diagnosis of ACM, confirming the dysfunctional adhesion hypothesis. Deregulation of integrin-αVβ6 and transforming growth factor-β signaling was identified as a central step toward fibrosis. A pilot in vivo drug test revealed this pathway as a promising target to ameliorate fibrosis. This highlights the value of this model to discern mechanisms of cardiac fibrosis and to identify and test novel treatment options for ACM.
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Affiliation(s)
- Camilla Schinner
- Department of Biomedicine, Section Anatomy (C. Schinner, H.F., A.Z., M.-T.W., M.R., P.H., C. Stüdle, P.I.M., V.S.), University of Basel, Switzerland
| | - Lifen Xu
- Department of Biomedicine, University Hospital Basel and University of Basel, Switzerland (L.X., V.L., G.M.K.)
| | - Henriette Franz
- Department of Biomedicine, Section Anatomy (C. Schinner, H.F., A.Z., M.-T.W., M.R., P.H., C. Stüdle, P.I.M., V.S.), University of Basel, Switzerland
| | - Aude Zimmermann
- Department of Biomedicine, Section Anatomy (C. Schinner, H.F., A.Z., M.-T.W., M.R., P.H., C. Stüdle, P.I.M., V.S.), University of Basel, Switzerland
| | - Marie-Therès Wanuske
- Department of Biomedicine, Section Anatomy (C. Schinner, H.F., A.Z., M.-T.W., M.R., P.H., C. Stüdle, P.I.M., V.S.), University of Basel, Switzerland
| | - Maitreyi Rathod
- Department of Biomedicine, Section Anatomy (C. Schinner, H.F., A.Z., M.-T.W., M.R., P.H., C. Stüdle, P.I.M., V.S.), University of Basel, Switzerland
| | - Pauline Hanns
- Department of Biomedicine, Section Anatomy (C. Schinner, H.F., A.Z., M.-T.W., M.R., P.H., C. Stüdle, P.I.M., V.S.), University of Basel, Switzerland
| | - Florian Geier
- Department of Biomedicine, Bioinformatics Core Facility (F.G.), University Hospital Basel, Switzerland
- Swiss Institute of Bioinformatics, Basel, Switzerland (F.G.)
| | - Pawel Pelczar
- Center for Transgenic Models (P.P.), University of Basel, Switzerland
| | - Yan Liang
- Department of Medicine, University of California San Diego (Y.L., F.S.)
| | - Vera Lorenz
- Department of Biomedicine, University Hospital Basel and University of Basel, Switzerland (L.X., V.L., G.M.K.)
| | - Chiara Stüdle
- Department of Biomedicine, Section Anatomy (C. Schinner, H.F., A.Z., M.-T.W., M.R., P.H., C. Stüdle, P.I.M., V.S.), University of Basel, Switzerland
| | - Piotr I. Maly
- Department of Biomedicine, Section Anatomy (C. Schinner, H.F., A.Z., M.-T.W., M.R., P.H., C. Stüdle, P.I.M., V.S.), University of Basel, Switzerland
| | - Silke Kauferstein
- Department of Legal Medicine, University Hospital Frankfurt, Goethe University, Frankfurt am Main, Germany (S.K., B.M.B.)
| | - Britt M. Beckmann
- Department of Legal Medicine, University Hospital Frankfurt, Goethe University, Frankfurt am Main, Germany (S.K., B.M.B.)
- Department of Medicine I, University Hospital, LMU Munich, Germany (B.M.B.)
| | - Farah Sheikh
- Department of Medicine, University of California San Diego (Y.L., F.S.)
| | - Gabriela M. Kuster
- Department of Biomedicine, University Hospital Basel and University of Basel, Switzerland (L.X., V.L., G.M.K.)
- Division of Cardiology (G.M.K.), University Hospital Basel, Switzerland
| | - Volker Spindler
- Department of Biomedicine, Section Anatomy (C. Schinner, H.F., A.Z., M.-T.W., M.R., P.H., C. Stüdle, P.I.M., V.S.), University of Basel, Switzerland
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10
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Cheung E, Xia Y, Caporini MA, Gilmore JL. Tools shaping drug discovery and development. BIOPHYSICS REVIEWS 2022; 3:031301. [PMID: 38505278 PMCID: PMC10903431 DOI: 10.1063/5.0087583] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 06/21/2022] [Indexed: 03/21/2024]
Abstract
Spectroscopic, scattering, and imaging methods play an important role in advancing the study of pharmaceutical and biopharmaceutical therapies. The tools more familiar to scientists within industry and beyond, such as nuclear magnetic resonance and fluorescence spectroscopy, serve two functions: as simple high-throughput techniques for identification and purity analysis, and as potential tools for measuring dynamics and structures of complex biological systems, from proteins and nucleic acids to membranes and nanoparticle delivery systems. With the expansion of commercial small-angle x-ray scattering instruments into the laboratory setting and the accessibility of industrial researchers to small-angle neutron scattering facilities, scattering methods are now used more frequently in the industrial research setting, and probe-less time-resolved small-angle scattering experiments are now able to be conducted to truly probe the mechanism of reactions and the location of individual components in complex model or biological systems. The availability of atomic force microscopes in the past several decades enables measurements that are, in some ways, complementary to the spectroscopic techniques, and wholly orthogonal in others, such as those related to nanomechanics. As therapies have advanced from small molecules to protein biologics and now messenger RNA vaccines, the depth of biophysical knowledge must continue to serve in drug discovery and development to ensure quality of the drug, and the characterization toolbox must be opened up to adapt traditional spectroscopic methods and adopt new techniques for unraveling the complexities of the new modalities. The overview of the biophysical methods in this review is meant to showcase the uses of multiple techniques for different modalities and present recent applications for tackling particularly challenging situations in drug development that can be solved with the aid of fluorescence spectroscopy, nuclear magnetic resonance spectroscopy, atomic force microscopy, and small-angle scattering.
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Affiliation(s)
- Eugene Cheung
- Moderna, 200 Technology Square, Cambridge, Massachusetts 02139, USA
| | - Yan Xia
- Moderna, 200 Technology Square, Cambridge, Massachusetts 02139, USA
| | - Marc A. Caporini
- Moderna, 200 Technology Square, Cambridge, Massachusetts 02139, USA
| | - Jamie L. Gilmore
- Moderna, 200 Technology Square, Cambridge, Massachusetts 02139, USA
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11
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Mitgau J, Franke J, Schinner C, Stephan G, Berndt S, Placantonakis DG, Kalwa H, Spindler V, Wilde C, Liebscher I. The N Terminus of Adhesion G Protein–Coupled Receptor GPR126/ADGRG6 as Allosteric Force Integrator. Front Cell Dev Biol 2022; 10:873278. [PMID: 35813217 PMCID: PMC9259995 DOI: 10.3389/fcell.2022.873278] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 05/12/2022] [Indexed: 12/15/2022] Open
Abstract
The adhesion G protein–coupled receptor (aGPCR) GPR126/ADGRG6 plays an important role in several physiological functions, such as myelination or peripheral nerve repair. This renders the receptor an attractive pharmacological target. GPR126 is a mechano-sensor that translates the binding of extracellular matrix (ECM) molecules to its N terminus into a metabotropic intracellular signal. To date, the structural requirements and the character of the forces needed for this ECM-mediated receptor activation are largely unknown. In this study, we provide this information by combining classic second-messenger detection with single-cell atomic force microscopy. We established a monoclonal antibody targeting the N terminus to stimulate GPR126 and compared it to the activation through its known ECM ligands, collagen IV and laminin 211. As each ligand uses a distinct mode of action, the N terminus can be regarded as an allosteric module that can fine-tune receptor activation in a context-specific manner.
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Affiliation(s)
- Jakob Mitgau
- Rudolf Schönheimer Institute for Biochemistry, Molecular Biochemistry, University of Leipzig, Leipzig, Germany
| | - Julius Franke
- Rudolf Schönheimer Institute for Biochemistry, Molecular Biochemistry, University of Leipzig, Leipzig, Germany
| | - Camilla Schinner
- Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Gabriele Stephan
- Department of Neurosurgery, Kimmel Center for Stem Cell Biology, Laura and Isaac Perlmutter Cancer Center, NYU Grossman School of Medicine, New York, NY, United States
| | - Sandra Berndt
- Rudolf Schönheimer Institute for Biochemistry, Molecular Biochemistry, University of Leipzig, Leipzig, Germany
| | - Dimitris G. Placantonakis
- Department of Neurosurgery, Kimmel Center for Stem Cell Biology, Laura and Isaac Perlmutter Cancer Center, NYU Grossman School of Medicine, New York, NY, United States
| | - Hermann Kalwa
- Rudolf-Boehm-Institute for Pharmacology and Toxicology, University of Leipzig, Leipzig, Germany
| | - Volker Spindler
- Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Caroline Wilde
- Rudolf Schönheimer Institute for Biochemistry, Molecular Biochemistry, University of Leipzig, Leipzig, Germany
| | - Ines Liebscher
- Rudolf Schönheimer Institute for Biochemistry, Molecular Biochemistry, University of Leipzig, Leipzig, Germany
- *Correspondence: Ines Liebscher,
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12
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Hiermaier M, Kugelmann D, Radeva MY, Didona D, Ghoreschi K, Farzan S, Hertl M, Waschke J. Pemphigus Foliaceus Autoantibodies Induce Redistribution Primarily of Extradesmosomal Desmoglein 1 in the Cell Membrane. Front Immunol 2022; 13:882116. [PMID: 35634274 PMCID: PMC9134081 DOI: 10.3389/fimmu.2022.882116] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 04/20/2022] [Indexed: 11/23/2022] Open
Abstract
The autoimmune dermatosis pemphigus foliaceus (PF) is predominantly caused by IgG autoantibodies against the desmosomal cadherin desmoglein (Dsg) 1. The exact mechanisms that lead to the characteristic epidermal blistering are not yet fully understood. In the present study, we used a variety of biophysical methods to examine the fate of membrane-bound Dsg1 after incubation with PF patients’ IgG. Dispase-based dissociation assays confirmed that PF-IgG used for this study reduced intercellular adhesion in a manner dependent on phospholipase C (PLC)/Ca2+ and extracellular signal-regulated kinase (ERK) 1/2 signaling. Atomic force microscopy (AFM) revealed that Dsg1 binding on single molecule level paralleled effects on keratinocyte adhesion under the different conditions. Stimulated emission depletion (STED) super-resolution microscopy was used to investigate the localization of Dsg1 after PF-IgG incubation for 24 h. Under control conditions, Dsg1 was found to be in part co-localized with desmoplakin and thus inside of desmosomes as well as extra-desmosomal along the cell border. Incubation with PF-IgG reduced the extra-desmosomal Dsg1 fraction. In line with this, fluorescence recovery after photobleaching (FRAP) experiments demonstrated a strongly reduced mobility of Dsg1 in the cell membrane after PF-IgG treatment indicating remaining Dsg1 molecules were primarily located inside desmosomes. Mechanistically, experiments confirmed the involvement of PLC/Ca2+ since inhibition of PLC or 1,4,5-trisphosphate (IP3) receptor to reduce cytosolic Ca2+ reverted the effects of PF-IgG on Dsg1 intra-membrane mobility and localization. Taken together, our findings suggest that during the first 24 h PF-IgG induce redistribution predominantly of membrane-bound extradesmosomal Dsg1 in a PLC/Ca2+ dependent manner whereas Dsg1-containing desmosomes remain.
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Affiliation(s)
- Matthias Hiermaier
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, München, Germany
| | - Daniela Kugelmann
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, München, Germany
| | - Mariya Y Radeva
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, München, Germany
| | - Dario Didona
- Department of Dermatology and Allergology, Philipps University, Marburg, Germany
| | - Kamran Ghoreschi
- Department of Dermatology, Venereology and Allergology, Charité-Universitätsmedizin Berlin, Berlin, Germany.,Department of Dermatology, University Medical Center, Eberhard Karls Universität Tübingen, Tübingen, Germany
| | - Solimani Farzan
- Department of Dermatology, Venereology and Allergology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Michael Hertl
- Department of Dermatology and Allergology, Philipps University, Marburg, Germany
| | - Jens Waschke
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, München, Germany
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13
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Beaussart A, Canonico F, Mazon H, Hidalgo J, Cianférani S, Le Cordier H, Kriznik A, Rahuel-Clermont S. Probing the mechanism of the peroxiredoxin decamer interaction with its reductase sulfiredoxin from the single molecule to the solution scale. NANOSCALE HORIZONS 2022; 7:515-525. [PMID: 35234779 DOI: 10.1039/d2nh00037g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Peroxiredoxins from the Prx1 subfamily (Prx) are highly regulated multifunctional proteins involved in oxidative stress response, redox signaling and cell protection. Prx is a homodimer that associates into a decamer. The monomer C-terminus plays intricate roles in Prx catalytic functions, decamer stability and interaction with its redox partner, the small reductase sulfiredoxin (Srx), that regulates the switching between Prx cellular functions. As only static structures of covalent Prx-Srx complexes have been reported, whether Srx binding dissociates the decameric assembly and how Prx subunit flexibility impacts complex formation are unknown. Here, we assessed the non-covalent interaction mechanism and dynamics in the solution of Saccharomyces cerevisiae Srx with the ten subunits of Prx Tsa1 at the decamer level via a combination of multiscale biophysical approaches including native mass spectrometry. We show that the ten subunits of the decamer can be saturated by ten Srx molecules and that the Tsa1 decamer in complex with Srx does not dissociate in solution. Furthermore, the binding events of atomic force microscopy (AFM) tip-grafted Srx molecules to Tsa1 individual subunits were relevant to the interactions between free molecules in solution. Combined with protein engineering and rapid kinetics, the observation of peculiar AFM force-distance signatures revealed that Tsa1 C-terminus flexibility controls Tsa1/Srx two-step binding and dynamics and determines the force-induced dissociation of Srx from each subunit of the decameric complex in a sequential or concerted mode. This combined approach from the solution to the single-molecule level offers promising prospects for understanding oligomeric protein interactions with their partners.
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Affiliation(s)
| | | | - Hortense Mazon
- Université de Lorraine, CNRS, IMoPA, F-54000 Nancy, France
| | - Jorge Hidalgo
- Université de Lorraine, CNRS, IMoPA, F-54000 Nancy, France
| | - Sarah Cianférani
- Laboratoire de Spectrométrie de Masse BioOrganique, Université de Strasbourg, CNRS, IPHC UMR 7178, 67000 Strasbourg, France
- Infrastructure Nationale de Protéomique ProFI - FR2048 CNRS CEA, 67087 Strasbourg, France
| | | | - Alexandre Kriznik
- Université de Lorraine, CNRS, IMoPA, F-54000 Nancy, France
- Université de Lorraine, CNRS, INSERM, UMS2008 IBSLor, Biophysics and Structural Biology core facility, F-54000 Nancy, France.
| | - Sophie Rahuel-Clermont
- Université de Lorraine, CNRS, IMoPA, F-54000 Nancy, France
- Université de Lorraine, CNRS, INSERM, UMS2008 IBSLor, Biophysics and Structural Biology core facility, F-54000 Nancy, France.
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14
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Büchau F, Vielmuth F, Waschke J, Magin TM. Bidirectional regulation of desmosome hyperadhesion by keratin isotypes and desmosomal components. Cell Mol Life Sci 2022; 79:223. [PMID: 35380280 PMCID: PMC8983532 DOI: 10.1007/s00018-022-04244-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 03/04/2022] [Accepted: 03/10/2022] [Indexed: 11/30/2022]
Abstract
Desmosomes are intercellular junctions which mediate cohesion and communication in tissues exposed to mechanical strain by tethering the intermediate filament cytoskeleton to the plasma membrane. While mature desmosomes are characterized by a hyperadhesive, Ca2+-independent state, they transiently loose this state during wound healing, pathogenesis and tissue regeneration. The mechanisms controlling the hyperadhesive state remain incompletely understood. Here, we show that upon Ca2+-induced keratinocyte differentiation, expression of keratin 17 (K17) prevents the formation of stable and hyperadhesive desmosomes, accompanied by a significant reduction of desmoplakin (DP), plakophilin-1 (PKP1), desmoglein-1 (Dsg1) and -3 (Dsg3) at intercellular cell borders. Atomic force microscopy revealed that both increased binding strength of desmoglein-3 molecules and amount of desmoglein-3 oligomers, known hallmarks of hyperadhesion, were reduced in K17- compared to K14-expressing cells. Importantly, overexpression of Dsg3 or DPII enhanced their localization at intercellular cell borders and increased the formation of Dsg3 oligomers, resulting in stable, hyperadhesive desmosomes despite the presence of K17. Notably, PKP1 was enriched in these desmosomes. Quantitative image analysis revealed that DPII overexpression contributed to desmosome hyperadhesion by increasing the abundance of K5/K17-positive keratin filaments in the proximity of desmosomes enriched in desmoglein-3. Thus, our data show that hyperadhesion can result from recruitment of keratin isotypes K5/K17 to desmosomes or from enhanced expression of DP and Dsg3 irrespective of keratin composition. The notion that hyperadhesive desmosomes failed to form in the absence of keratins underscores the essential role of keratins and suggest bidirectional control mechanisms at several levels.
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Affiliation(s)
- Fanny Büchau
- Institute of Biology, Division of Cell and Developmental Biology, University of Leipzig, Philipp-Rosenthal-Straße 55, 04103, Leipzig, Germany.
| | - Franziska Vielmuth
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Jens Waschke
- Chair of Vegetative Anatomy, Institute of Anatomy, Faculty of Medicine, LMU Munich, Munich, Germany
| | - Thomas M Magin
- Institute of Biology, Division of Cell and Developmental Biology, University of Leipzig, Philipp-Rosenthal-Straße 55, 04103, Leipzig, Germany
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15
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Fuchs M, Kugelmann D, Schlegel N, Vielmuth F, Waschke J. Desmoglein 2 can undergo Ca2+-dependent interactions with both desmosomal and classical cadherins including E-cadherin and N-cadherin. Biophys J 2022; 121:1322-1335. [PMID: 35183520 PMCID: PMC9034291 DOI: 10.1016/j.bpj.2022.02.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 08/23/2021] [Accepted: 02/15/2022] [Indexed: 11/02/2022] Open
Abstract
Desmoglein (Dsg) 2 is a ubiquitously expressed desmosomal cadherin. Particularly, it is present in all cell types forming desmosomes, including epithelial cells and cardiac myocytes and is upregulated in the autoimmune skin disease pemphigus. Thus, we here characterized the binding properties of Dsg2 in more detail using atomic force microscopy (AFM). Dsg2 exhibits homophilic interactions and also heterophilic interactions with the desmosomal cadherin desmocollin (Dsc) 2, and further with the classical cadherins E-cadherin (E-Cad) and N-cadherin (N-Cad), which may be relevant for cross talk between desmosomes and adherens junctions in epithelia and cardiac myocytes. We found that all homo- and heterophilic interactions were Ca2+-dependent. All binding forces observed are in the same force range, i.e., 30 to 40 pN, except for the Dsg2/E-Cad unbinding force, which with 45 pN is significantly higher. To further characterize the nature of the interactions, we used tryptophan, a critical amino acid required for trans-interaction, and a tandem peptide (TP) designed to cross-link Dsg isoforms. TP was sufficient to prevent the tryptophan-induced loss of Dsg2 interaction with the desmosomal cadherins Dsg2 and Dsc2; however, not with the classical cadherins E-Cad and N-Cad, indicating that the interaction modes of Dsg2 with desmosomal and classical cadherins differ. TP rescued the tryptophan-induced loss of Dsg2 binding on living enterocytes, suggesting that interaction with desmosomal cadherins may be more relevant. In summary, the data suggest that the ubiquitous desmosomal cadherin Dsg2 enables the cross talk with adherens junctions by interacting with multiple binding partners with implications for proper adhesive function in healthy and diseased states.
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16
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Pisapati AV, Cao W, Anderson KR, Jones G, Holick KH, Whiteaker P, Im W, Zhang XF, Miwa JM. Biophysical characterization of lynx-nicotinic receptor interactions using atomic force microscopy. FASEB Bioadv 2021; 3:1034-1042. [PMID: 34938964 PMCID: PMC8664008 DOI: 10.1096/fba.2021-00012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 08/03/2021] [Accepted: 08/30/2021] [Indexed: 11/11/2022] Open
Abstract
Nicotinic acetylcholine receptors (nAChRs) are broadly expressed in the central and peripheral nervous systems, playing essential roles in cholinergic neurotransmission. The lynx family proteins, a subset of the Ly6/uPAR superfamily expressed in multiple brain regions, have been shown to bind to nAChRs and modulate their function via allosteric regulation. The binding interactions between lynx and nAChRs, however, have not been systematically quantified and compared. In this work, we characterized the interactions between lynx1 or lynx2 and α3β4- or α7-nAChRs using single-molecule atomic force microscopy (AFM). The AFM technique allows the quantification of the off-rate of lynx-nAChR binding and of the energetic barrier width between the bound state and transition state, providing a biophysical means to compare the selectivity of lynx proteins for nAChR subtypes. Results indicate that lynx1 has a marginal preference for α7- over α3β4-nAChRs. Strikingly, lynx2 exhibits a two order of magnitude stronger affinity for α3β4- compared to α7-nAChRs. Together, the AFM assay serves as a valuable tool for the biophysical characterization of lynx-nAChR binding affinities. Revealing the differential affinities of lynx proteins for nAChR subtypes will help elucidate how lynx regulates nAChR-dependent functions in the brain, including nicotine addiction and other critical pathways.
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Affiliation(s)
- Avani V. Pisapati
- Department of BioengineeringLehigh UniversityBethlehemPennsylvaniaUSA
| | - Wenpeng Cao
- Department of BioengineeringLehigh UniversityBethlehemPennsylvaniaUSA
| | | | - Griffin Jones
- Department of Biological SciencesLehigh UniversityBethlehemPennsylvaniaUSA
| | | | - Paul Whiteaker
- Division of NeurobiologyBarrow Neurological Institute, St. Joseph's Hospital and Medical CenterLehigh UniversityPhoenixArizonaUSA
| | - Wonpil Im
- Department of BioengineeringLehigh UniversityBethlehemPennsylvaniaUSA
- Department of Biological SciencesLehigh UniversityBethlehemPennsylvaniaUSA
- Department of ChemistryLehigh UniversityBethlehemPennsylvaniaUSA
| | - X. Frank Zhang
- Department of BioengineeringLehigh UniversityBethlehemPennsylvaniaUSA
- Department of Mechanical Engineering and MechanicsLehigh UniversityBethlehemPennsylvaniaUSA
| | - Julie M. Miwa
- Department of Biological SciencesLehigh UniversityBethlehemPennsylvaniaUSA
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17
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Parreira P, Martins MCL. The biophysics of bacterial infections: Adhesion events in the light of force spectroscopy. Cell Surf 2021; 7:100048. [PMID: 33665520 PMCID: PMC7898176 DOI: 10.1016/j.tcsw.2021.100048] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2018] [Revised: 08/10/2020] [Accepted: 12/03/2020] [Indexed: 02/08/2023] Open
Abstract
Bacterial infections are the most eminent public health challenge of the 21st century. The primary step leading to infection is bacterial adhesion to the surface of host cells or medical devices, which is mediated by a multitude of molecular interactions. At the interface of life sciences and physics, last years advances in atomic force microscopy (AFM)-based force spectroscopy techniques have made possible to measure the forces driving bacteria-cell and bacteria-materials interactions on a single molecule/cell basis (single molecule/cell force spectroscopy). Among the bacteria-(bio)materials surface interactions, the life-threatening infections associated to medical devices involving Staphylococcus aureus and Escherichia coli are the most eminent. On the other hand, Pseudomonas aeruginosa binding to the pulmonary and urinary tract or the Helicobacter pylori binding to the gastric mucosa, are classical examples of bacteria-host cell interactions that end in serious infections. As we approach the end of the antibiotic era, acquisition of a deeper knowledge of the fundamental forces involved in bacteria - host cells/(bio)materials surface adhesion is crucial for the identification of new ligand-binding events and its assessment as novel targets for alternative anti-infective therapies. This article aims to highlight the potential of AFM-based force spectroscopy for new targeted therapies development against bacterial infections in which adhesion plays a pivotal role and does not aim to be an extensive overview on the AFM technical capabilities and theory of single molecule force spectroscopy.
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Affiliation(s)
- Paula Parreira
- INEB – Instituto de Engenharia Biomédica, Universidade do Porto, Portugal
- i3S – Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal
| | - M. Cristina L. Martins
- INEB – Instituto de Engenharia Biomédica, Universidade do Porto, Portugal
- i3S – Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Portugal
- ICBAS – Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Portugal
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18
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Das S, Agarwal DK, Mandal B, Rao VR, Kundu T. Detection of the Chilli Leaf Curl Virus Using an Attenuated Total Reflection-Mediated Localized Surface-Plasmon-Resonance-Based Optical Platform. ACS OMEGA 2021; 6:17413-17423. [PMID: 34278127 PMCID: PMC8280655 DOI: 10.1021/acsomega.1c01702] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 06/09/2021] [Indexed: 05/16/2023]
Abstract
The development of a nanoparticle-based optical platform has been presented as a biosensor for detecting target-specific plant virus DNA. The binding dynamics of gold nanoparticles has been studied on the amine-functionalized surface by the attenuated total reflection (ATR)-based evanescent wave absorption method monitoring the localized surface plasmon resonance (LSPR). The developed surface was established as a refractive index sensor by monitoring the LSPR absorption peak of gold nanoparticles. This nanoparticle-immobilized surface was explored to establish as a biosensing platform with target-specific immunoglobulin (IgG) antibody-antigen interaction. The IgG concentration-dependent variation of absorbance was correlated with the refractive index change. After successfully establishing this ATR configuration as an LSPR-based biosensor, the single-stranded DNA of the chilli leaf curl virus was detected using its complementary DNA sequence as a receptor. The limit of detection of this sensor was determined to be 1.0 μg/mL for this target viral DNA. This ATR absorption technique has enormous potential as an LSPR based nano-biosensor for the detection of other begomoviruses.
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Affiliation(s)
- Sonatan Das
- Centre
for Research in Nanotechnology and Science, Indian Institute of Technology Bombay, Mumbai 400076, India
| | - Dilip Kumar Agarwal
- Department
of Physics, Indian Institute of Technology
Bombay, Mumbai 400076, India
| | - Bikash Mandal
- Advanced
Centre for Plant Virology, Indian Agricultural
Research Institute, Pusa, New Delhi, Delhi 110012, India
| | - V. Ramgopal Rao
- Centre
for Research in Nanotechnology and Science, Indian Institute of Technology Bombay, Mumbai 400076, India
- Department
of Electrical Engineering, Indian Institute
of Technology Bombay, Mumbai 400076, India
| | - Tapanendu Kundu
- Centre
for Research in Nanotechnology and Science, Indian Institute of Technology Bombay, Mumbai 400076, India
- Department
of Physics, Indian Institute of Technology
Bombay, Mumbai 400076, India
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19
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Wanuske M, Brantschen D, Schinner C, Stüdle C, Walter E, Hiermaier M, Vielmuth F, Waschke J, Spindler V. Clustering of desmosomal cadherins by desmoplakin is essential for cell-cell adhesion. Acta Physiol (Oxf) 2021; 231:e13609. [PMID: 33354837 DOI: 10.1111/apha.13609] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 12/19/2020] [Accepted: 12/20/2020] [Indexed: 12/14/2022]
Abstract
AIM Desmoplakin (Dp) is a crucial component of the desmosome, a supramolecular cell junction complex anchoring intermediate filaments. The mechanisms how Dp modulates cell-cell adhesion are only partially understood. Here, we studied the impact of Dp on the function of desmosomal adhesion molecules, desmosome turnover and intercellular adhesion. METHODS CRISPR/Cas9 was used for gene editing of human keratinocytes which were characterized by Western blot and immunostaining. Desmosomal ultrastructure and function were assessed by electron microscopy and cell adhesion assays. Single molecule binding properties and localization of desmosomal cadherins were studied by atomic force microscopy and super-resolution imaging. RESULTS Knockout (ko) of Dp impaired cell cohesion to drastically higher extents as ko of another desmosomal protein, plakoglobin (Pg). In contrast to Pg ko, desmosomes were completely absent in Dp ko. Binding properties of the desmosomal adhesion molecules desmocollin (Dsc) 3 and desmoglein (Dsg) 3 remained unaltered under loss of Dp. Dp was required for assembling desmosomal cadherins into large clusters, as Dsg2 and Dsc3, adhesion molecules primarily localized within desmosomes, were redistributed into small puncta in the cell membrane of Dp ko cells. Additional silencing of desmosomal cadherins in Dp ko did not further increase loss of intercellular adhesion. CONCLUSION Our data demonstrate that Dp is essential for desmosome formation but does not influence intercellular adhesion on the level of individual cadherin binding properties. Rather, macro-clustering of desmosomal adhesion molecules through Dp is crucial. These results may help to better understand severe diseases which are caused by Dp dysfunction.
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Affiliation(s)
- Marie‐Therès Wanuske
- Department of Biomedicine University of Basel Basel Switzerland
- Faculty of Medicine Ludwig‐Maximilians‐Universität Munich Munich Germany
| | | | - Camilla Schinner
- Department of Biomedicine University of Basel Basel Switzerland
- Faculty of Medicine Ludwig‐Maximilians‐Universität Munich Munich Germany
| | - Chiara Stüdle
- Department of Biomedicine University of Basel Basel Switzerland
| | - Elias Walter
- Faculty of Medicine Ludwig‐Maximilians‐Universität Munich Munich Germany
| | - Matthias Hiermaier
- Department of Biomedicine University of Basel Basel Switzerland
- Faculty of Medicine Ludwig‐Maximilians‐Universität Munich Munich Germany
| | - Franziska Vielmuth
- Faculty of Medicine Ludwig‐Maximilians‐Universität Munich Munich Germany
| | - Jens Waschke
- Faculty of Medicine Ludwig‐Maximilians‐Universität Munich Munich Germany
| | - Volker Spindler
- Department of Biomedicine University of Basel Basel Switzerland
- Faculty of Medicine Ludwig‐Maximilians‐Universität Munich Munich Germany
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20
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Leitner M, Brummeir J, Plaimer GO, Kefer I, Poturnayova A, Hianik T, Ebner A. DNA building blocks for AFM tip functionalization: An easy, fast and stable strategy. Methods 2021; 197:54-62. [PMID: 33677061 DOI: 10.1016/j.ymeth.2021.02.021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 02/13/2021] [Accepted: 02/27/2021] [Indexed: 10/22/2022] Open
Abstract
Biosensing atomic force microscopy (AFM) offers the unique feature to determine the energy landscape of a bimolecular interaction at the real single molecule level. Furthermore, simultaneous and label-free mapping of molecular recognition and the determination of sample topography at the nanoscale gets possible. A prerequisite and one of the major parts in biosensing AFM are the bio-functionalized AFM tips. In the past decades, different approaches for tip functionalization have been developed. Using these functionalization strategies, several biological highly relevant interactions at the single molecule level have been explored. For the most common approach, the use of a heterobifunctional poly(ethylenglycol) crosslinker, a broad range of linkers for different chemical coupling strategies is available. Nonetheless, the time consuming functionalization protocol as well as the broad distribution of rupture length reduces the possibility of automation and may reduce the accuracy of the results. Here we present a stable and fast forward approach based on tetra-functional DNA tetrahedra. A fast functionalization and a sharp defined distribution of rupture length gets possible with low effort and high success rate. We tested the performance on the classical avidin biotin system by using tetrahedra with three disulfide legs for stable and site directed coupling to gold coated tips and a biotinylated end at the fourth vertex. A special advantage appears when working with a DNA aptamer as sensing molecule. In this case, the fourth strand can be extended by a certain DNA sequence complementary to the linkage part of an aptamer. This AFM tip functionalization protocol was applied on thrombin using DNA aptamers directed against the fibrinogen binding side of human thrombin.
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Affiliation(s)
- Michael Leitner
- Institute of Biophysics, Johannes Kepler University, Gruberstrasse 40, 4020 Linz, Austria
| | - Julian Brummeir
- Institute of Biophysics, Johannes Kepler University, Gruberstrasse 40, 4020 Linz, Austria
| | - Gernot Oswald Plaimer
- Institute of Biophysics, Johannes Kepler University, Gruberstrasse 40, 4020 Linz, Austria
| | - Isabel Kefer
- Institute of Biophysics, Johannes Kepler University, Gruberstrasse 40, 4020 Linz, Austria
| | - Alexandra Poturnayova
- Center of Biosciences, Slovak Academy of Sciences, Dúbravská cesta 9, 840 05 Bratislava, Slovakia
| | - Tibor Hianik
- Faculty of Mathematics, Physics and Informatics, Comenius University, Mlynská dolina F1, 842 48 Bratislava, Slovakia
| | - Andreas Ebner
- Institute of Biophysics, Johannes Kepler University, Gruberstrasse 40, 4020 Linz, Austria.
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21
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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.
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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
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22
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Francius G, Petit F, Clément E, Chekli Y, Ghigo JM, Beloin C, Duval JFL. On the strong connection between nanoscale adhesion of Yad fimbriae and macroscale attachment of Yad-decorated bacteria to glycosylated, hydrophobic and hydrophilic surfaces. NANOSCALE 2021; 13:1257-1272. [PMID: 33404575 DOI: 10.1039/d0nr06840c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Yad fimbriae are currently viewed as versatile bacterial adhesins able to significantly mediate host or plant-pathogen recognition and contribute to the persistence of Escherichia coli in both the environment and within hosts. To date, however, the underlying adhesion process of Yad fimbriae on surfaces defined by controlled coating chemistries has not been evaluated on the relevant molecular scale. In this work, the interaction forces operational between Yad fimbriae expressed by genetically modified E. coli and self-assembled monolayers (SAM) differing in terms of charge, hydrophobicity or the nature of decorating sugar units are quantified by Single Molecule Force Spectroscopy (SMFS) on the nanoscale. It is found that the adhesion of Yad fimbriae onto probes functionalized with xylose is as strong as that measured with probes decorated with anti-Yad antibodies (ca. 80 to 300 pN). In contrast, the interactions of Yad with galactose, lactose, mannose, -OH, -NH2, -COOH and -CH3 terminated SAMs are clearly non-specific. Interpretation of SMFS measurements on the basis of worm-like-chain modeling for polypeptide nanomechanics further leads to the estimates of the maximal extension of Yad fimbriae upon stretching, of their persistence length and of their polydispersity. Finally, we show for the first time a strong correlation between the adhesion properties of Yad-decorated bacteria determined from conventional macroscopic counting methods and the molecular adhesion capacity of Yad fimbriae. This demonstration advocates the effort that should be made to understand on the nanoscale level the interactions between fimbriae and their cognate ligands. The results could further help the design of potential anti-adhesive molecules or surfaces to better fight against the virulence of bacterial pathogens.
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Affiliation(s)
- Grégory Francius
- Université de Lorraine, LCPME, UMR 7564, Villers-lès-Nancy, F-54600, France.
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23
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Sigmund AM, Steinert LS, Egu DT, Bayerbach FC, Waschke J, Vielmuth F. Dsg2 Upregulation as a Rescue Mechanism in Pemphigus. Front Immunol 2020; 11:581370. [PMID: 33193387 PMCID: PMC7655986 DOI: 10.3389/fimmu.2020.581370] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 09/28/2020] [Indexed: 12/20/2022] Open
Abstract
In pemphigus vulgaris (PV), autoantibodies directed against the desmosomal cadherin desmoglein (Dsg) 3 cause loss of intercellular adhesion. It is known that Dsg3 interactions are directly inhibited by autoantibody binding and that Dsg2 is upregulated in epidermis of PV patients. Here, we investigated whether heterophilic Dsg2-Dsg3 interactions occur and would modulate PV pathogenesis. Dsg2 was upregulated in PV patients’ biopsies and in a human ex vivo pemphigus skin model. Immunoprecipitation and cell-free atomic force microscopy (AFM) experiments demonstrated heterophilic Dsg2-Dsg3 interactions. Similarly, in Dsg3-deficient keratinocytes with severely disturbed intercellular adhesion Dsg2 was upregulated in the desmosome containing fraction. AFM revealed that Dsg2-Dsg3 heterophilic interactions showed binding frequency, strength, Ca2+-dependency and catch-bond behavior comparable to homophilic Dsg3-Dsg3 or homophilic Dsg2-Dsg2 interactions. However, heterophilic Dsg2-Dsg3 interactions had a longer lifetime compared to homophilic Dsg2-Dsg2 interactions and PV autoantibody-induced direct inhibition was significantly less pronounced for heterophilic Dsg2-Dsg3 interactions compared to homophilic Dsg3 interactions. In contrast, a monoclonal anti-Dsg2 inhibitory antibody reduced heterophilic Dsg2-Dsg3 and homophilic Dsg2-Dsg2 binding to the same degree and further impaired intercellular adhesion in Dsg3-deficient keratinocytes. Taken together, the data demonstrate that Dsg2 undergoes heterophilic interactions with Dsg3, which may attenuate autoantibody-induced loss of keratinocyte adhesion in pemphigus.
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Affiliation(s)
- Anna M Sigmund
- Department I, Faculty of Medicine, Institute of Anatomy and Cell Biology, Ludwig-Maximilians-Universität, Munich, Germany
| | - Letyfee S Steinert
- Department I, Faculty of Medicine, Institute of Anatomy and Cell Biology, Ludwig-Maximilians-Universität, Munich, Germany
| | - Desalegn T Egu
- Department I, Faculty of Medicine, Institute of Anatomy and Cell Biology, Ludwig-Maximilians-Universität, Munich, Germany
| | - Franziska C Bayerbach
- Department I, Faculty of Medicine, Institute of Anatomy and Cell Biology, Ludwig-Maximilians-Universität, Munich, Germany
| | - Jens Waschke
- Department I, Faculty of Medicine, Institute of Anatomy and Cell Biology, Ludwig-Maximilians-Universität, Munich, Germany
| | - Franziska Vielmuth
- Department I, Faculty of Medicine, Institute of Anatomy and Cell Biology, Ludwig-Maximilians-Universität, Munich, Germany
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24
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Hiermaier M, Kliewe F, Schinner C, Stüdle C, Maly IP, Wanuske MT, Rötzer V, Endlich N, Vielmuth F, Waschke J, Spindler V. The Actin-Binding Protein α-Adducin Modulates Desmosomal Turnover and Plasticity. J Invest Dermatol 2020; 141:1219-1229.e11. [PMID: 33098828 DOI: 10.1016/j.jid.2020.09.022] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2019] [Revised: 09/08/2020] [Accepted: 09/09/2020] [Indexed: 01/01/2023]
Abstract
Intercellular adhesion is essential for tissue integrity and homeostasis. Desmosomes are abundant in the epidermis and the myocardium-tissues, which are under constantly changing mechanical stresses. Yet, it is largely unclear whether desmosomal adhesion can be rapidly adapted to changing demands, and the mechanisms underlying desmosome turnover are only partially understood. In this study we show that the loss of the actin-binding protein α-adducin resulted in reduced desmosome numbers and prevented the ability of cultured keratinocytes or murine epidermis to withstand mechanical stress. This effect was not primarily caused by decreased levels or impaired adhesive properties of desmosomal molecules but rather by altered desmosome turnover. Mechanistically, reduced cortical actin density in α-adducin knockout keratinocytes resulted in increased mobility of the desmosomal adhesion molecule desmoglein 3 and impaired interactions with E-cadherin, a crucial step in desmosome formation. Accordingly, the loss of α-adducin prevented increased membrane localization of desmoglein 3 in response to cyclic stretch or shear stress. Our data demonstrate the plasticity of desmosomal molecules in response to mechanical stimuli and unravel a mechanism of how the actin cytoskeleton indirectly shapes intercellular adhesion by restricting the membrane mobility of desmosomal molecules.
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Affiliation(s)
- Matthias Hiermaier
- Department of Biomedicine, University of Basel, Basel, Switzerland; Faculty of Medicine, Ludwig-Maximilians-Universität Munich, Munich, Germany
| | - Felix Kliewe
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany
| | - Camilla Schinner
- Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Chiara Stüdle
- Department of Biomedicine, University of Basel, Basel, Switzerland
| | - I Piotr Maly
- Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Marie-Therès Wanuske
- Department of Biomedicine, University of Basel, Basel, Switzerland; Faculty of Medicine, Ludwig-Maximilians-Universität Munich, Munich, Germany
| | - Vera Rötzer
- Faculty of Medicine, Ludwig-Maximilians-Universität Munich, Munich, Germany
| | - Nicole Endlich
- Department of Anatomy and Cell Biology, University Medicine Greifswald, Greifswald, Germany
| | - Franziska Vielmuth
- Faculty of Medicine, Ludwig-Maximilians-Universität Munich, Munich, Germany
| | - Jens Waschke
- Faculty of Medicine, Ludwig-Maximilians-Universität Munich, Munich, Germany
| | - Volker Spindler
- Department of Biomedicine, University of Basel, Basel, Switzerland; Faculty of Medicine, Ludwig-Maximilians-Universität Munich, Munich, Germany.
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25
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Fuchs M, Sigmund AM, Waschke J, Vielmuth F. Desmosomal Hyperadhesion Is Accompanied with Enhanced Binding Strength of Desmoglein 3 Molecules. Biophys J 2020; 119:1489-1500. [PMID: 33031738 DOI: 10.1016/j.bpj.2020.09.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 08/24/2020] [Accepted: 09/08/2020] [Indexed: 12/26/2022] Open
Abstract
Intercellular adhesion of keratinocytes depends critically on desmosomes that, during maturation, acquire a hyperadhesive and thus Ca2+ independent state. Here, we investigated the roles of desmoglein (Dsg) 3 and plakophilins (Pkps) in hyperadhesion. Atomic force microscopy single molecule force mappings revealed increased Dsg3 molecules but not Dsg1 molecules binding strength in murine keratinocytes. However, keratinocytes lacking Dsg3 or Pkp1 or 3 revealed reduced Ca2+ independency. In addition, Pkp1- or 3-deficient keratinocytes did not exhibit changes in Dsg3 binding on the molecular level. Further, wild-type keratinocytes showed increased levels of Dsg3 oligomers during acquisition of hyperadhesion, and Pkp1 deficiency abolished the formation of Ca2+ independent Dsg3 oligomers. In concordance, immunostaining for Dsg1 but not for Dsg3 was reduced after 24 h of Ca2+ chelation in an ex vivo human skin model, suggesting that desmosomal cadherins may have different roles during acquisition of hyperadhesion. Taken together, these data indicate that hyperadhesion may not be a state acquired by entire desmosomes but rather is paralleled by enhanced binding of specific Dsg isoforms such as Dsg3, a process for which plaque proteins including Pkp 1 and 3 are required as well.
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Affiliation(s)
- Michael Fuchs
- Institute of Anatomy, Faculty of Medicine, Ludwig-Maximilians-Universität Munich, Munich, Germany
| | - Anna Magdalena Sigmund
- Institute of Anatomy, Faculty of Medicine, Ludwig-Maximilians-Universität Munich, Munich, Germany
| | - Jens Waschke
- Institute of Anatomy, Faculty of Medicine, Ludwig-Maximilians-Universität Munich, Munich, Germany
| | - Franziska Vielmuth
- Institute of Anatomy, Faculty of Medicine, Ludwig-Maximilians-Universität Munich, Munich, Germany.
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26
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Qin J, Zhang M, Guan Y, Li C, Ma X, Rankl C, Tang J. Investigation of the interaction between MeCP2 methyl-CpG binding domain and methylated DNA by single molecule force spectroscopy. Anal Chim Acta 2020; 1124:52-59. [PMID: 32534675 DOI: 10.1016/j.aca.2020.05.029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 05/07/2020] [Accepted: 05/11/2020] [Indexed: 11/19/2022]
Abstract
MeCP2 is an essential transcriptional repressor that mediates transcriptional inhibition by binding to methylated DNA. The binding specificity of MeCP2 protein to methylated DNA was considered to depend on its methyl-CpG binding domain (MBD). In this study, we used atomic force microscope based single-molecular force spectroscopy to investigate the interaction of MeCP2 MBD and methylated DNA. The specific interaction forces of the MeCP2 MBD-methylated DNA complexes were measured for the first time. The dynamics was also investigated by measuring the unbinding force of the complex at different loading rates. In addition, the distribution of unbinding forces and binding probabilities of MeCP2 MBD and different DNA were studied at the same loading rate. It was found that MeCP2 MBD had weak interaction with hemi-methylated and unmethylated DNA compared to methylated DNA. This work revealed the binding characteristics of MeCP2 MBD and methylated DNA at the single-molecule level. It provides a new idea for exploring the molecular mechanism of MeCP2 in regulating methylation signals.
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Affiliation(s)
- Juan Qin
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, PR China; University of Science and Technology of China, Hefei, 230026, PR China
| | - Miaomiao Zhang
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, PR China; University of Science and Technology of China, Hefei, 230026, PR China
| | - Yanxue Guan
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, PR China; University of Science and Technology of China, Hefei, 230026, PR China
| | - Chen Li
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, PR China; University of Science and Technology of China, Hefei, 230026, PR China
| | - Xingxing Ma
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, PR China; University of Science and Technology of China, Hefei, 230026, PR China
| | - Christian Rankl
- RECENDT Research Center for Non Destructive Testing GmbH, Science Park 2/2.OG, Altenberger Straße 69, 4040 Linz, Austria
| | - Jilin Tang
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, PR China; University of Science and Technology of China, Hefei, 230026, PR China.
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27
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Yeruva S, Kempf E, Egu DT, Flaswinkel H, Kugelmann D, Waschke J. Adrenergic Signaling-Induced Ultrastructural Strengthening of Intercalated Discs via Plakoglobin Is Crucial for Positive Adhesiotropy in Murine Cardiomyocytes. Front Physiol 2020; 11:430. [PMID: 32508670 PMCID: PMC7253624 DOI: 10.3389/fphys.2020.00430] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 04/08/2020] [Indexed: 11/26/2022] Open
Abstract
Intercalated discs (ICDs), which connect adjacent cardiomyocytes, are composed of desmosomes, adherens junctions (AJs) and gap junctions (GJs). Previous data demonstrated that adrenergic signaling enhances cardiac myocyte cohesion, referred to as positive adhesiotropy, via PKA-mediated phosphorylation of plakoglobin (PG). However, it was unclear whether positive adhesiotropy caused ultrastructural modifications of ICDs. Therefore, we further investigated the role of PG in adrenergic signaling-mediated ultrastructural changes in the ICD of cardiomyocytes. Quantitative transmission electron microscopy (TEM) analysis of ICD demonstrated that cAMP elevation caused significant elongation of area composita and thickening of the ICD plaque, paralleled by enhanced cardiomyocyte cohesion, in WT but not PG-deficient cardiomyocytes. STED microscopy analysis supported that cAMP elevation ex vivo enhanced overlap of desmoglein-2 (Dsg2) and N-cadherin (N-cad) staining in ICDs of WT but not PG-deficient cardiomyocytes. For dynamic analyses, we utilized HL-1 cardiomyocytes, in which cAMP elevation induced translocation of Dsg2 and PG but not of N-cad to cell junctions. Nevertheless, depletion of N-cad but not of Dsg2 resulted in a decrease in basal cell cohesion whereas positive adhesiotropy was abrogated in monolayers depleted for either Dsg2 or N-cad. In the WT mice, ultrastrutural changes observed after cAMP elevation were paralleled by phosphorylation of PG at serine 665. Our data demonstrate that in murine hearts adrenergic signaling enhanced N-cad and Dsg2 in the ICD paralleled by ultrastrutural strengthening of ICDs and that effects induced by positive adhesiotropy were strictly dependent on Pg.
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Affiliation(s)
- Sunil Yeruva
- Institute of Anatomy and Cell Biology, Faculty of Medicine, Ludwig-Maximilians-Universität Munich, Munich, Germany
| | - Ellen Kempf
- Institute of Anatomy and Cell Biology, Faculty of Medicine, Ludwig-Maximilians-Universität Munich, Munich, Germany
| | - Desalegn Tadesse Egu
- Institute of Anatomy and Cell Biology, Faculty of Medicine, Ludwig-Maximilians-Universität Munich, Munich, Germany
| | | | - Daniela Kugelmann
- Institute of Anatomy and Cell Biology, Faculty of Medicine, Ludwig-Maximilians-Universität Munich, Munich, Germany
| | - Jens Waschke
- Institute of Anatomy and Cell Biology, Faculty of Medicine, Ludwig-Maximilians-Universität Munich, Munich, Germany
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28
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Zhu R, Sandtner W, Ahiable JEA, Newman AH, Freissmuth M, Sitte HH, Hinterdorfer P. Allosterically Linked Binding Sites in Serotonin Transporter Revealed by Single Molecule Force Spectroscopy. Front Mol Biosci 2020; 7:99. [PMID: 32656227 PMCID: PMC7325972 DOI: 10.3389/fmolb.2020.00099] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Accepted: 05/01/2020] [Indexed: 01/24/2023] Open
Abstract
Crystal structures and experiments relying on the tools of molecular pharmacology reported conflicting results on ligand binding sites in neurotransmitter/sodium symporters (NSS). We explored the number and functionality of ligand binding sites of NSS in a physiological setting by designing novel tools for atomic force microscopy (AFM). These allow for directly measuring the interaction forces between the serotonin transporter (SERT) and the antidepressant S-citalopram (S-CIT) on the single molecule level: the AFM cantilever tips were functionalized with S-CIT via a flexible polyethylene glycol (PEG) linker. The tip chemistry was validated by specific force measurements and recognition imaging on CHO cells. Two distinct populations of characteristic binding strengths of S-CIT binding to SERT were revealed in Na+-containing buffer. In contrast, in Li+-containing buffer, SERT showed only low force interactions. Conversely, the vestibular mutant SERT-G402H merely displayed the high force population. These observations provide physical evidence for the existence of two binding sites in SERT. The dissociation rate constant of both binding sites was extracted by varying the dynamics of the force-probing experiments. Competition experiments revealed that the two sites are allosterically coupled and exert reciprocal modulation.
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Affiliation(s)
- Rong Zhu
- Institute of Biophysics, Johannes Kepler University Linz, Linz, Austria
| | - Walter Sandtner
- Institute of Pharmacology and the Gaston H. Glock Research Laboratories for Exploratory Drug Development, Center of Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Joan E A Ahiable
- Institute of Biophysics, Johannes Kepler University Linz, Linz, Austria
| | - Amy Hauck Newman
- Medicinal Chemistry Section, Molecular Targets and Medications Discovery Branch, National Institute on Drug Abuse, Intramural Research Program, Baltimore, MD, United States
| | - Michael Freissmuth
- Institute of Pharmacology and the Gaston H. Glock Research Laboratories for Exploratory Drug Development, Center of Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Harald H Sitte
- Institute of Pharmacology and the Gaston H. Glock Research Laboratories for Exploratory Drug Development, Center of Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
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29
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Schinner C, Erber BM, Yeruva S, Schlipp A, Rötzer V, Kempf E, Kant S, Leube RE, Mueller TD, Waschke J. Stabilization of desmoglein-2 binding rescues arrhythmia in arrhythmogenic cardiomyopathy. JCI Insight 2020; 5:130141. [PMID: 32376797 DOI: 10.1172/jci.insight.130141] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 04/08/2020] [Indexed: 12/28/2022] Open
Abstract
Arrhythmogenic cardiomyopathy (AC) is a genetic disease causing arrhythmia and sudden cardiac death with only symptomatic therapy available at present. Mutations of desmosomal proteins, including desmoglein-2 (Dsg2) and plakoglobin (Pg), are the major cause of AC and have been shown to lead to impaired gap junction function. Recent data indicated the involvement of anti-Dsg2 autoantibodies in AC pathogenesis. We applied a peptide to stabilize Dsg2 binding similar to a translational approach to pemphigus, which is caused by anti-desmoglein autoantibodies. We provide evidence that stabilization of Dsg2 binding by a linking peptide (Dsg2-LP) is efficient to rescue arrhythmia in an AC mouse model immediately upon perfusion. Dsg2-LP, designed to cross-link Dsg2 molecules in proximity to the known binding pocket, stabilized Dsg2-mediated interactions on the surface of living cardiomyocytes as revealed by atomic force microscopy and induced Dsg2 oligomerization. Moreover, Dsg2-LP rescued disrupted cohesion induced by siRNA-mediated Pg or Dsg2 depletion or l-tryptophan, which was applied to impair overall cadherin binding. Dsg2-LP rescued connexin-43 mislocalization and conduction irregularities in response to impaired cardiomyocyte cohesion. These results demonstrate that stabilization of Dsg2 binding by Dsg2-LP can serve as a novel approach to treat arrhythmia in patients with AC.
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Affiliation(s)
- Camilla Schinner
- Faculty of Medicine, Ludwig-Maximilians-Universität (LMU) Munich, Munich, Germany.,Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Bernd Markus Erber
- Faculty of Medicine, Ludwig-Maximilians-Universität (LMU) Munich, Munich, Germany
| | - Sunil Yeruva
- Faculty of Medicine, Ludwig-Maximilians-Universität (LMU) Munich, Munich, Germany
| | - Angela Schlipp
- Faculty of Medicine, Ludwig-Maximilians-Universität (LMU) Munich, Munich, Germany
| | - Vera Rötzer
- Faculty of Medicine, Ludwig-Maximilians-Universität (LMU) Munich, Munich, Germany
| | - Ellen Kempf
- Faculty of Medicine, Ludwig-Maximilians-Universität (LMU) Munich, Munich, Germany
| | - Sebastian Kant
- Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Aachen, Germany
| | - Rudolf E Leube
- Institute of Molecular and Cellular Anatomy, RWTH Aachen University, Aachen, Germany
| | - Thomas D Mueller
- Department of Molecular Plant Physiology and Biophysics, Julius-von-Sachs Institute for Biosciences, Julius-Maximilians-Universität, Würzburg, Germany
| | - Jens Waschke
- Faculty of Medicine, Ludwig-Maximilians-Universität (LMU) Munich, Munich, Germany
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30
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Lansakara TI, Morris HS, Singh P, Kohen A, Tivanski AV. Rigid Double-Stranded DNA Linkers for Single Molecule Enzyme-Drug Interaction Measurements Using Molecular Recognition Force Spectroscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:4174-4183. [PMID: 32233509 DOI: 10.1021/acs.langmuir.9b03495] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Single-molecule studies can reveal the distribution of states and interactions between ligand-enzyme complexes not accessible for most studies that measure a large ensemble average response of many molecules. Furthermore, in some biological applications, the information regarding the outliers, not the average of measured properties, can be more important. The high spatial and force resolution provided by atomic force microscopy (AFM) under physiological conditions has been utilized in this study to quantify the force-distance relations of enzyme-drug interactions. Different immobilization techniques of the protein to a surface and the drug to AFM tip were quantitatively compared to improve the accuracy and precision of the measurement. Protein that is directly bound to the surface, forming a monolayer, was compared to enzyme molecules bound to the surface with rigid double-stranded (ds) DNA spacers. These surfaces immobilization techniques were studied with the drug bound directly to the AFM tip and drug bound via flexible poly(ethylene glycol) and rigid dsDNA linkers. The activity of the enzyme was found to be not significantly altered by immobilization methods relative to its activity in solution. The findings indicate that the approach for studying drug-enzyme interaction based on rigid dsDNA linker on the surface and either flexible or rigid linker on the tip affords straightforward, highly specific, reproducible, and accurate force measurements with a potential for single-molecule level studies. The method could facilitate in-depth examination of a broad spectrum of biological targets and potential drugs.
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Affiliation(s)
| | - Holly S Morris
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
| | - Priyanka Singh
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
| | - Amnon Kohen
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
| | - Alexei V Tivanski
- Department of Chemistry, University of Iowa, Iowa City, Iowa 52242, United States
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Zhu C, Monti S, Mathew AP. Evaluation of nanocellulose interaction with water pollutants using nanocellulose colloidal probes and molecular dynamic simulations. Carbohydr Polym 2020; 229:115510. [DOI: 10.1016/j.carbpol.2019.115510] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 09/22/2019] [Accepted: 10/19/2019] [Indexed: 01/01/2023]
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32
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Beaussart A, El-Kirat-Chatel S. Microbial adhesion and ultrastructure from the single-molecule to the single-cell levels by Atomic Force Microscopy. Cell Surf 2019; 5:100031. [PMID: 32743147 PMCID: PMC7389263 DOI: 10.1016/j.tcsw.2019.100031] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 07/04/2019] [Accepted: 07/05/2019] [Indexed: 12/29/2022] Open
Abstract
In the last decades, atomic force microscopy (AFM) has evolved towards an accurate and lasting tool to study the surface of living cells in physiological conditions. Through imaging, single-molecule force spectroscopy and single-cell force spectroscopy modes, AFM allows to decipher at multiple scales the morphology and the molecular interactions taking place at the cell surface. Applied to microbiology, these approaches have been used to elucidate biophysical properties of biomolecules and to directly link the molecular structures to their function. In this review, we describe the main methods developed for AFM-based microbial surface analysis that we illustrate with examples of molecular mechanisms unravelled with unprecedented resolution.
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33
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Ho V, Herman-Bausier P, Shaw C, Conrad KA, Garcia-Sherman MC, Draghi J, Dufrene YF, Lipke PN, Rauceo JM. An Amyloid Core Sequence in the Major Candida albicans Adhesin Als1p Mediates Cell-Cell Adhesion. mBio 2019; 10:e01766-19. [PMID: 31594814 PMCID: PMC6786869 DOI: 10.1128/mbio.01766-19] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 09/09/2019] [Indexed: 01/05/2023] Open
Abstract
The human fungal commensal Candida albicans can become a serious opportunistic pathogen in immunocompromised hosts. The C. albicans cell adhesion protein Als1p is a highly expressed member of a large family of paralogous adhesins. Als1p can mediate binding to epithelial and endothelial cells, is upregulated in infections, and is important for biofilm formation. Als1p includes an amyloid-forming sequence at amino acids 325 to 331, identical to the sequence in the paralogs Als5p and Als3p. Therefore, we mutated Val326 to test whether this sequence is important for activity. Wild-type Als1p (Als1pWT) and Als1p with the V326N mutation (Als1pV326N) were expressed at similar levels in a Saccharomyces cerevisiae surface display model. Als1pV326N cells adhered to bovine serum albumin (BSA)-coated beads similarly to Als1pWT cells. However, cells displaying Als1pV326N showed visibly smaller aggregates and did not fluoresce in the presence of the amyloid-binding dye Thioflavin-T. A new analysis tool for single-molecule force spectroscopy-derived surface mapping showed that statistically significant force-dependent Als1p clustering occurred in Als1pWT cells but was absent in Als1pV326N cells. In single-cell force spectroscopy experiments, strong cell-cell adhesion was dependent on an intact amyloid core sequence on both interacting cells. Thus, the major adhesin Als1p interacts through amyloid-like β-aggregation to cluster adhesin molecules in cis on the cell surface as well as in trans to form cell-cell bonds.IMPORTANCE Microbial cell surface adhesins control essential processes such as adhesion, colonization, and biofilm formation. In the opportunistic fungal pathogen Candida albicans, the agglutinin-like sequence (ALS) gene family encodes eight cell surface glycoproteins that mediate adherence to biotic and abiotic surfaces and cell-cell aggregation. Als proteins are critical for commensalism and virulence. Their activities include attachment and invasion of endothelial and epithelial cells, morphogenesis, and formation of biofilms on host tissue and indwelling medical catheters. At the molecular level, Als5p-mediated cell-cell aggregation is dependent on the formation of amyloid-like nanodomains between Als5p-expressing cells. A single-site mutation to valine 326 abolishes cellular aggregation and amyloid formation. Our results show that the binding characteristics of Als1p follow a mechanistic model similar to Als5p, despite its differential expression and biological roles.
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Affiliation(s)
- Vida Ho
- Department of Sciences, John Jay College of the City University of New York, New York, New York, USA
| | | | - Christopher Shaw
- Department of Sciences, John Jay College of the City University of New York, New York, New York, USA
| | - Karen A Conrad
- Department of Sciences, John Jay College of the City University of New York, New York, New York, USA
| | - Melissa C Garcia-Sherman
- Biology Department, Brooklyn College of the City University of New York, Brooklyn, New York, USA
| | - Jeremy Draghi
- Biology Department, Brooklyn College of the City University of New York, Brooklyn, New York, USA
| | - Yves F Dufrene
- Institute of Life Sciences, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Peter N Lipke
- Biology Department, Brooklyn College of the City University of New York, Brooklyn, New York, USA
| | - Jason M Rauceo
- Department of Sciences, John Jay College of the City University of New York, New York, New York, USA
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34
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Fuchs M, Foresti M, Radeva MY, Kugelmann D, Keil R, Hatzfeld M, Spindler V, Waschke J, Vielmuth F. Plakophilin 1 but not plakophilin 3 regulates desmoglein clustering. Cell Mol Life Sci 2019; 76:3465-3476. [PMID: 30949721 PMCID: PMC11105395 DOI: 10.1007/s00018-019-03083-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 02/15/2019] [Accepted: 03/25/2019] [Indexed: 12/25/2022]
Abstract
Plakophilins (Pkp) are desmosomal plaque proteins crucial for desmosomal adhesion and participate in the regulation of desmosomal turnover and signaling. However, direct evidence that Pkps regulate clustering and molecular binding properties of desmosomal cadherins is missing. Here, keratinocytes lacking either Pkp1 or 3 in comparison to wild type (wt) keratinocytes were characterized with regard to their desmoglein (Dsg) 1- and 3-binding properties and their capability to induce Dsg3 clustering. As revealed by atomic force microscopy (AFM), both Pkp-deficient keratinocyte cell lines showed reduced membrane availability and binding frequency of Dsg1 and 3 at cell borders. Extracellular crosslinking and AFM cluster mapping demonstrated that Pkp1 but not Pkp3 is required for Dsg3 clustering. Accordingly, Dsg3 overexpression reconstituted cluster formation in Pkp3- but not Pkp1-deficient keratinocytes as shown by AFM and STED experiments. Taken together, these data demonstrate that both Pkp1 and 3 regulate Dsg membrane availability, whereas Pkp1 but not Pkp3 is required for Dsg3 clustering.
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Affiliation(s)
- Michael Fuchs
- Faculty of Medicine, Institute of Anatomy, Ludwig-Maximilians-Universität Munich, Pettenkoferstr. 11, 80336, Munich, Germany
| | - Marco Foresti
- Faculty of Medicine, Institute of Anatomy, Ludwig-Maximilians-Universität Munich, Pettenkoferstr. 11, 80336, Munich, Germany
| | - Mariya Y Radeva
- Faculty of Medicine, Institute of Anatomy, Ludwig-Maximilians-Universität Munich, Pettenkoferstr. 11, 80336, Munich, Germany
| | - Daniela Kugelmann
- Faculty of Medicine, Institute of Anatomy, Ludwig-Maximilians-Universität Munich, Pettenkoferstr. 11, 80336, Munich, Germany
| | - Rene Keil
- Division of Pathobiochemistry, Institute of Molecular Medicine, Martin-Luther-University Halle-Wittenberg, Halle, Germany
| | - Mechthild Hatzfeld
- Division of Pathobiochemistry, Institute of Molecular Medicine, Martin-Luther-University Halle-Wittenberg, Halle, Germany
| | - Volker Spindler
- Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Jens Waschke
- Faculty of Medicine, Institute of Anatomy, Ludwig-Maximilians-Universität Munich, Pettenkoferstr. 11, 80336, Munich, Germany.
| | - Franziska Vielmuth
- Faculty of Medicine, Institute of Anatomy, Ludwig-Maximilians-Universität Munich, Pettenkoferstr. 11, 80336, Munich, Germany.
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35
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Pickering AC, Vitry P, Prystopiuk V, Garcia B, Höök M, Schoenebeck J, Geoghegan JA, Dufrêne YF, Fitzgerald JR. Host-specialized fibrinogen-binding by a bacterial surface protein promotes biofilm formation and innate immune evasion. PLoS Pathog 2019; 15:e1007816. [PMID: 31216354 PMCID: PMC6602291 DOI: 10.1371/journal.ppat.1007816] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 07/01/2019] [Accepted: 05/06/2019] [Indexed: 11/18/2022] Open
Abstract
Fibrinogen is an essential part of the blood coagulation cascade and a major component of the extracellular matrix in mammals. The interface between fibrinogen and bacterial pathogens is an important determinant of the outcome of infection. Here, we demonstrate that a canine host-restricted skin pathogen, Staphylococcus pseudintermedius, produces a cell wall-associated protein (SpsL) that has evolved the capacity for high strength binding to canine fibrinogen, with reduced binding to fibrinogen of other mammalian species including humans. Binding occurs via the surface-expressed N2N3 subdomains, of the SpsL A-domain, to multiple sites in the fibrinogen α-chain C-domain by a mechanism analogous to the classical dock, lock, and latch binding model. Host-specific binding is dependent on a tandem repeat region of the fibrinogen α-chain, a region highly divergent between mammals. Of note, we discovered that the tandem repeat region is also polymorphic in different canine breeds suggesting a potential influence on canine host susceptibility to S. pseudintermedius infection. Importantly, the strong host-specific fibrinogen-binding interaction of SpsL to canine fibrinogen is essential for bacterial aggregation and biofilm formation, and promotes resistance to neutrophil phagocytosis, suggesting a key role for the interaction during pathogenesis. Taken together, we have dissected a bacterial surface protein-ligand interaction resulting from the co-evolution of host and pathogen that promotes host-specific innate immune evasion and may contribute to its host-restricted ecology. Many bacterial pathogens are specialized for a single host-species and rarely cause infections of other hosts. Our understanding of the bacterial factors underpinning host-specificity are limited. Here we demonstrate that a canine host-restricted bacterial pathogen, Staphylococcus pseudintermedius, produces a surface protein (SpsL) that has the ability to preferentially bind to canine fibrinogen with high strength. This host-specific interaction has evolved via binding to a tandem repeat region of the fibrinogen α-chain which is divergent among mammalian species. Importantly, we found that the strong binding interaction with canine fibrinogen promotes bacterial aggregation and biofilm formation as well as inhibiting neutrophil phagocytosis. Our findings reveal the host-adaptive evolution of a key bacterium-host interaction that promotes evasion of the host immune response.
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Affiliation(s)
- Amy C. Pickering
- The Roslin Institute and Edinburgh Infectious Diseases, University of Edinburgh, Easter Bush Campus, Edinburgh, Scotland, United Kingdom
| | - Pauline Vitry
- Institute of Life Sciences, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Valeriia Prystopiuk
- Institute of Life Sciences, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Brandon Garcia
- Department of Microbiology and Immunology, Brody school of Medicine, East Carolina University, Greenville, North Carolina, United States of America
| | - Magnus Höök
- Center for Infectious and Inflammatory Diseases, Texas A&M Health Science Center, Houston, Texas, United States of America
| | - Jeffrey Schoenebeck
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Campus, Edinburgh, Scotland, United Kingdom
| | - Joan A. Geoghegan
- Department of Microbiology, Moyne Institute of Preventive Medicine, School of Genetics and Microbiology, Trinity College Dublin, Dublin, Ireland
| | - Yves F. Dufrêne
- Institute of Life Sciences, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
- Walloon Excellence in Life Sciences and Biotechnology, Wavre, Belgium
| | - J. Ross Fitzgerald
- The Roslin Institute and Edinburgh Infectious Diseases, University of Edinburgh, Easter Bush Campus, Edinburgh, Scotland, United Kingdom
- * E-mail:
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36
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Meir M, Burkard N, Ungewiß H, Diefenbacher M, Flemming S, Kannapin F, Germer CT, Schweinlin M, Metzger M, Waschke J, Schlegel N. Neurotrophic factor GDNF regulates intestinal barrier function in inflammatory bowel disease. J Clin Invest 2019; 129:2824-2840. [PMID: 31205031 DOI: 10.1172/jci120261] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 05/03/2019] [Indexed: 12/12/2022] Open
Abstract
Impaired intestinal epithelial barrier (IEB) function with loss of desmosomal junctional protein desmoglein 2 (DSG2) is a hallmark in the pathogenesis of inflammatory bowel disease (IBD). While previous studies have reported that glial cell line-derived neurotrophic factor (GDNF) promotes IEB function, the mechanisms are poorly understood. We hypothesized that GDNF is involved in the loss of DSG2, resulting in impaired IEB function as seen in IBD. In the inflamed intestine of patients with IBD, there was a decrease in GDNF concentrations accompanied by a loss of DSG2, changes of the intermediate filament system, and increased phosphorylation of p38 MAPK and cytokeratins. DSG2-deficient and RET-deficient Caco2 cells revealed that GDNF specifically recruits DSG2 to the cell borders, resulting in increased DSG2-mediated intercellular adhesion via the RET receptor. Challenge of Caco2 cells and enteroids with proinflammatory cytokines as well as dextran sulfate sodium-induced (DSS-induced) colitis in C57Bl/6 mice led to impaired IEB function with reduced DSG2 mediated by p38 MAPK-dependent phosphorylation of cytokeratins. GDNF blocked all inflammation-induced changes in the IEB. GDNF attenuates inflammation-induced impairment of IEB function caused by the loss of DSG2 through p38 MAPK-dependent phosphorylation of cytokeratin. The reduced GDNF in patients with IBD indicates a disease-relevant contribution to the development of IEB dysfunction.
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Affiliation(s)
- Michael Meir
- Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Wuerzburg, Wuerzburg, Germany
| | - Natalie Burkard
- Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Wuerzburg, Wuerzburg, Germany
| | - Hanna Ungewiß
- Institute of Anatomy and Cell Biology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Markus Diefenbacher
- Department of Biochemistry and Molecular Biochemistry, University of Wuerzburg, Wuerzburg, Germany
| | - Sven Flemming
- Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Wuerzburg, Wuerzburg, Germany
| | - Felix Kannapin
- Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Wuerzburg, Wuerzburg, Germany
| | - Christoph-Thomas Germer
- Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Wuerzburg, Wuerzburg, Germany
| | - Matthias Schweinlin
- Department for Tissue Engineering and Regenerative Medicine, University Hospital Wuerzburg, Wuerzburg, Germany
| | - Marco Metzger
- Department for Tissue Engineering and Regenerative Medicine, University Hospital Wuerzburg, Wuerzburg, Germany.,Fraunhofer ISC, Translational Centre Regenerative Medicine TLC-RT, Wuerzburg, Germany
| | - Jens Waschke
- Institute of Anatomy and Cell Biology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Nicolas Schlegel
- Department of General, Visceral, Vascular and Pediatric Surgery, University Hospital Wuerzburg, Wuerzburg, Germany
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37
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Walter E, Vielmuth F, Wanuske MT, Seifert M, Pollmann R, Eming R, Waschke J. Role of Dsg1- and Dsg3-Mediated Signaling in Pemphigus Autoantibody-Induced Loss of Keratinocyte Cohesion. Front Immunol 2019; 10:1128. [PMID: 31178865 PMCID: PMC6543754 DOI: 10.3389/fimmu.2019.01128] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 05/03/2019] [Indexed: 12/13/2022] Open
Abstract
Pemphigus is an autoimmune dermatosis in which mucocutaneous blisters are induced primarily by autoantibodies against Desmoglein (Dsg) 1 and 3. Pemphigus vulgaris (PV) usually is associated with autoantibodies against Dsg3 whereas pemphigus foliaceus (PF) patients present autoantibodies against Dsg1. Several signaling pathways were proposed to cause loss of keratinocyte adhesion. However, relevance of different signaling pathways and role of Dsg1 and 3 to trigger signaling are not fully understood. Here, we show that Ca2+ chelation reduced PV-IgG- and PF-IgG-mediated loss of HaCaT keratinocyte cohesion whereas EGFR inhibition did not inhibit effects of PF-IgG. PV-IgG activated EGFR in a Src-dependent manner whereas both PV-IgG and PF-IgG caused Ca2+ influx independent of EGFR. ERK activation was Src-dependent in response to PV-IgG but not PF-IgG. To delineate the roles of Dsg isoforms to trigger signaling pathways, Dsg3- and Dsg2-deficient HaCaT keratinocyte cell lines were generated using CRISPR/Cas9. Dsg3- but not Dsg2-deficient cells were protected against PV-IgG-induced loss of cell adhesion. Ca2+ influx and ERK activation in response to PF-IgG were preserved in both cell lines.
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Affiliation(s)
- Elias Walter
- Institute of Anatomy and Cell Biology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Franziska Vielmuth
- Institute of Anatomy and Cell Biology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Marie-Therès Wanuske
- Institute of Anatomy and Cell Biology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Matthias Seifert
- Institute of Anatomy and Cell Biology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Robert Pollmann
- Department of Dermatology and Allergology, Philipps-Universität Marburg, Marburg, Germany
| | - Rüdiger Eming
- Department of Dermatology and Allergology, Philipps-Universität Marburg, Marburg, Germany
| | - Jens Waschke
- Institute of Anatomy and Cell Biology, Ludwig-Maximilians-Universität München, Munich, Germany
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38
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Abstract
Crosslinking of proteins for their irreversible immobilization on surfaces is a proven and popular method. However, many protocols lead to random orientation and the formation of undefined or even inactive by-products. Most concepts to obtain a more targeted conjugation or immobilization requires the recombinant modification of at least one binding partner, which is often impractical or prohibitively expensive. Here a novel method is presented, which is based on the chemical preactivation of Protein A or G with selected conventional crosslinkers. In a second step, the antibody is added, which is subsequently crosslinked in the Fc part. This leads to an oriented and covalent immobilization of the immunoglobulin with a very high yield. Protocols for Protein A and Protein G with murine and human IgG are presented. This method may be useful for the preparation of columns for affinity chromatography, immunoprecipitation, antibodies conjugated to magnetic particles, permanent and oriented immobilization of antibodies in biosensor systems, microarrays, microtitration plates or any other system, where the loss of antibodies needs to be avoided, and maximum binding capacity is desired. This method is directly applicable even to antibodies in crude cell culture supernatants, raw sera or protein-stabilized antibody preparations without any purification nor enrichment of the IgG. This new method delivered much higher signals as a traditional method and, hence, seems to be preferable in many applications.
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39
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Ren L, Ma Z, Li Q, Zhao W, Wang Y, Wang H, Shen L, Zhang C, Fang X, Yu J. Identifying a Membrane-Type 2 Matrix Metalloproteinase-Targeting Peptide for Human Lung Cancer Detection and Targeting Chemotherapy with Functionalized Mesoporous Silica. ACS APPLIED BIO MATERIALS 2019; 2:397-405. [PMID: 35016363 DOI: 10.1021/acsabm.8b00633] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Membrane-type 2 matrix metalloproteinase (MT2-MMP) is critical for the aggressive lung tumor growth, progression, and metastasis. Here, to obtain the peptides in binding specifically to MT2-MMP, a phage-displayed 12 peptide library was used and the affinity of peptides toward MT2-MMP was identified by multitest methods. The results showed that a specific MT2-MMP-targeting peptide with the sequence of HHRLHSAPPPQA (MT2-AF5p) exhibited a high specificity and strong affinity against lung tumors. To further achieve specific targeting and precise therapeutic effects, MT2-AF5p was conjugated onto fluorescent mesoporous silica nanoparticles (FMSN-NH2) and loaded with doxorubicin (DOX) to construct a chemotherapeutic drug-targeting delivery system (DOX-loaded FMSN@MT2-AF5p). The DOX-loaded FMSN@MT2-AF5p achieved a boost in DOX release in an acidic environment. Most importantly, FMSN@MT2-AF5p efficiently targeted the tumor area, as seen in the fluorescent imaging ex vivo. The novel peptide-functionalized nanoparticles with a good biocompatibility are promising for clinical use as a precise targeting nanodrug for lung cancer diagnosis and therapy.
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Affiliation(s)
- Li Ren
- College of Food Science and Engineering, Jilin University, 5333 Xi'an Street, Changchun 130062, People's Republic of China.,State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, People's Republic of China.,Key Laboratory of Molecular Enzymology and Enzyme Engineering of the Ministry of Education, Jilin University, 2699 Qianjin Street, Changchun 130012, People's Republic of China
| | - Zheng Ma
- Department of Thoracic Surgery, Qilu Hospital of Shandong University, 107 Wenhuaxi Road, Jinan 250012, People's Republic of China
| | - Qinglan Li
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, People's Republic of China
| | - Weidong Zhao
- State Key Laboratory of Electroanalytical Chemistry, Research Center of Biomembranomics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun 130022, People's Republic of China
| | - Ye Wang
- The Life Science College, Jilin University, 2699 Qianjin Street, Changchun 130012, People's Republic of China
| | - Hongda Wang
- State Key Laboratory of Electroanalytical Chemistry, Research Center of Biomembranomics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun 130022, People's Republic of China
| | - Liqiao Shen
- Key Laboratory of Molecular Enzymology and Enzyme Engineering of the Ministry of Education, Jilin University, 2699 Qianjin Street, Changchun 130012, People's Republic of China
| | - Chengkai Zhang
- Key Laboratory of Molecular Enzymology and Enzyme Engineering of the Ministry of Education, Jilin University, 2699 Qianjin Street, Changchun 130012, People's Republic of China
| | - Xuexun Fang
- Key Laboratory of Molecular Enzymology and Enzyme Engineering of the Ministry of Education, Jilin University, 2699 Qianjin Street, Changchun 130012, People's Republic of China
| | - Jihong Yu
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, People's Republic of China
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40
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Ebner A, Wildling L, Gruber HJ. Functionalization of AFM Tips and Supports for Molecular Recognition Force Spectroscopy and Recognition Imaging. Methods Mol Biol 2019; 1886:117-151. [PMID: 30374865 DOI: 10.1007/978-1-4939-8894-5_7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Linking of sensor molecules (e.g., antibodies) to an AFM tip converts it into a biosensor by which single target molecules (e.g., antigens) can be detected and localized on the sample surface. Moreover, the mechanism of interaction can be studied by force spectroscopy if purified target molecules are linked to an ultra-flat surface, such as mica or silicon (nitride). Rapid imaging of the binding sites and force spectroscopy studies are greatly facilitated if 6-10 nm long polyethylene glycol (PEG) chains are used as flexible tethers between the sensor molecule and the tip. Here, we describe a set of methods by which a variety of proteins, oligonucleotides, or small molecules can be tethered to silicon (nitride) tips or to mica. Methods are included which afford site-specific and oriented coupling of the sensor molecules.
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Affiliation(s)
- A Ebner
- Institute of Biophysics, Johannes Kepler University Linz, Linz, Austria
| | - L Wildling
- Institute of Biophysics, Johannes Kepler University Linz, Linz, Austria
| | - H J Gruber
- Institute of Biophysics, Johannes Kepler University Linz, Linz, Austria.
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41
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Gu Z, Wang J, Miao B, Zhao L, Liu X, Wu D, Li J. Highly sensitive AlGaN/GaN HEMT biosensors using an ethanolamine modification strategy for bioassay applications. RSC Adv 2019; 9:15341-15349. [PMID: 35514822 PMCID: PMC9064203 DOI: 10.1039/c9ra02055a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Accepted: 05/09/2019] [Indexed: 12/21/2022] Open
Abstract
In this paper, we propose a highly efficient surface modification strategy on an AlGaN/GaN high electron mobility transistor (HEMT), where ethanolamine (EA) was utilized to functionalize the surface of GaN and provided amphoteric amine groups for probe molecular immobilization for bioassay application. The molecular gated-AlGaN/GaN HEMT was utilized for pH and prostate-specific antigen (PSA) detection to verify its performance as a biosensor. Benefitting from the high coating quality on the GaN surface, the performance of our biosensor is drastically improved compared to other AlGaN/GaN HEMT based pH and PSA biosensors reported before. Our molecular gated-AlGaN/GaN HEMT biosensor has achieved good static electrical performance for pH sensing, such as high sensitivity, good linearity and chemical stability. Moreover, after further immobilization of PSA antibody onto the EA aminated GaN surface, the limit of detection (LOD) for PSA detection is as low as 1 fg mL−1 in PBS buffer, which has reached an at least two orders of magnitude decrease compared to any other AlGaN/GaN HEMT based PSA biosensor reported before. And the sensitivity of our PSA biosensor has achieved a substantial increase, reaching up to 2.04% for 100 ng mL−1. The measurements of pH and PSA utilizing the EA modified AlGaN/GaN HEMT biosensor indicate that the surface modification strategy on the GaN proposed in this paper can effectively improve the performance of the AlGaN/GaN HEMT based biosensor, which demonstrates a promising application prospect in the AlGaN/GaN HEMT based biological detection field. We propose a highly efficient surface modification strategy on an AlGaN/GaN high electron mobility transistor, where ethanolamine was utilized to functionalize the surface of GaN and provided amphoteric amine groups for bioassay application.![]()
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Affiliation(s)
- Zhiqi Gu
- School of Nano Technology and Nano Bionics
- University of Science and Technology of China
- Hefei 230026
- China
- i-Lab
| | - Jin Wang
- i-Lab
- Suzhou Institute of Nano-Tech and Nano-Bionics
- Chinese Academy of Sciences
- Suzhou 215125
- People's Republic of China
| | - Bin Miao
- i-Lab
- Suzhou Institute of Nano-Tech and Nano-Bionics
- Chinese Academy of Sciences
- Suzhou 215125
- People's Republic of China
| | - Lei Zhao
- i-Lab
- Suzhou Institute of Nano-Tech and Nano-Bionics
- Chinese Academy of Sciences
- Suzhou 215125
- People's Republic of China
| | - Xinsheng Liu
- i-Lab
- Suzhou Institute of Nano-Tech and Nano-Bionics
- Chinese Academy of Sciences
- Suzhou 215125
- People's Republic of China
| | - Dongmin Wu
- School of Nano Technology and Nano Bionics
- University of Science and Technology of China
- Hefei 230026
- China
- i-Lab
| | - Jiadong Li
- School of Nano Technology and Nano Bionics
- University of Science and Technology of China
- Hefei 230026
- China
- i-Lab
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42
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Abstract
Atomic force microscopy (AFM) is a very versatile tool for studying biological samples at nanometer-scale resolution. The cell membrane plays a key role in compartmentalization, nutrient transportation, and signal transduction, while the structural feature of both sides of the membrane remains elusive. Here we describe our methods for the preparation of the cell membrane from the red blood cells and nucleated cells. High-resolution AFM topographs reveal substructural details of both sides of the cell membrane. The structure composition of cell membrane can be directly observed by time-lapse AFM and the positional information of membrane proteins can be located by molecular recognition.
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Affiliation(s)
- Mingjun Cai
- Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, People's Republic of China
| | - Hongda Wang
- Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, People's Republic of China.
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43
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Ren L, Li Q, Ma Z, Wang Y, Li H, Shen L, Yu J, Fang X. Quantum dots tethered membrane type 3 matrix metalloproteinase-targeting peptide for tumor optical imaging. J Mater Chem B 2018; 6:7719-7727. [PMID: 32254894 DOI: 10.1039/c8tb02025f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Membrane type matrix metalloproteinases (MT-MMPs) play important roles in malignant tumor progression through the degradation of the extracellular matrix and signal transduction. However, a member of the family, MT3-MMP, has attracted the least concern compared with other MT-MMPs. Here, a novel MT3-MMP-targeting peptide with high affinity and specificity has been developed by a phage-display peptide screening technology and multiple biophysics measurements, including single-molecule recognition force spectroscopy and isothermal titration calorimetry. The binding peptides are conjugated on the surface of CdSe/ZnS quantum dots (QDs) and consequently acted as a ligand that specifically targets MT3-MMP overexpressed tumor cells. The imaging nanoprobes used QDs as the photographic developer for optical imaging in vivo. The nanoprobes exhibited a desirable targeting effect and generated good biodistribution profiles for visualization and imaging of MT3-MMP overexpressed tumor. The peptide could be useful to evaluate the distribution and expression of MT3-MMP. Furthermore, the peptide-functionalized QDs show potential application for cancer diagnosis.
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Affiliation(s)
- Li Ren
- College of Food Science and Engineering, Jilin University, 5333 Xi'an Street, Changchun, Jilin 130062, P. R. China
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44
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Bönisch E, Oh YJ, Anzengruber J, Hager FF, López-Guzmán A, Zayni S, Hinterdorfer P, Kosma P, Messner P, Duda KA, Schäffer C. Lipoteichoic acid mediates binding of a Lactobacillus S-layer protein. Glycobiology 2018; 28:148-158. [PMID: 29309573 PMCID: PMC5993097 DOI: 10.1093/glycob/cwx102] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Accepted: 12/06/2017] [Indexed: 01/06/2023] Open
Abstract
The Gram-positive lactic acid bacterium Lactobacillus buchneri CD034 is covered by a two-dimensional crystalline, glycoproteinaceous cell surface (S-) layer lattice. While lactobacilli are extensively exploited as cell surface display systems for applied purposes, questions about how they stick their cell wall together are remaining open. This also includes the identification of the S-layer cell wall ligand. In this study, lipoteichoic acid was isolated from the L. buchneri CD034 cell wall as a significant fraction of the bacterium's cell wall glycopolymers, structurally characterized and analyzed for its potential to mediate binding of the S-layer to the cell wall. Combined component analyses and 1D- and 2D-nuclear magnetic resonance spectroscopy (NMR) revealed the lipoteichoic acid to be composed of on average 31 glycerol-phosphate repeating units partially substituted with α-d-glucose, and with an α-d-Galp(1→2)-α-d-Glcp(1→3)-1,2-diacyl-sn-Gro glycolipid anchor. The specificity of binding between the L. buchneri CD034 S-layer protein and purified lipoteichoic acid as well as their interaction force of about 45 pN were obtained by single-molecule force spectroscopy; this value is in the range of typical ligand-receptor interactions. This study sheds light on a functional implication of Lactobacillus cell wall architecture by showing direct binding between lipoteichoic acid and the S-layer of L. buchneri CD034.
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Affiliation(s)
- Eva Bönisch
- Department of NanoBiotechnology, NanoGlycobiology unit, Universität für Bodenkultur Wien, Muthgasse 11, Austria
| | - Yoo Jin Oh
- Institute of Biophysics, Johannes-Kepler University Linz, A-4020 Linz, Austria.,Keysight Technologies Austria GmbH, A-4020 Linz, Austria
| | - Julia Anzengruber
- Department of NanoBiotechnology, NanoGlycobiology unit, Universität für Bodenkultur Wien, Muthgasse 11, Austria
| | - Fiona F Hager
- Department of NanoBiotechnology, NanoGlycobiology unit, Universität für Bodenkultur Wien, Muthgasse 11, Austria
| | - Arturo López-Guzmán
- Department of NanoBiotechnology, NanoGlycobiology unit, Universität für Bodenkultur Wien, Muthgasse 11, Austria
| | - Sonja Zayni
- Department of NanoBiotechnology, NanoGlycobiology unit, Universität für Bodenkultur Wien, Muthgasse 11, Austria
| | - Peter Hinterdorfer
- Institute of Biophysics, Johannes-Kepler University Linz, A-4020 Linz, Austria
| | - Paul Kosma
- Department of Chemistry, Institute of Organic Chemistry, Universität für Bodenkultur Wien, Muthgasse 18, A-1190 Vienna, Austria
| | - Paul Messner
- Department of NanoBiotechnology, NanoGlycobiology unit, Universität für Bodenkultur Wien, Muthgasse 11, Austria
| | - Katarzyna A Duda
- Department of NanoBiotechnology, NanoGlycobiology unit, Universität für Bodenkultur Wien, Muthgasse 11, Austria.,Junior Group of Allergobiochemistry, Research Center Borstel, Leibniz-Center for Medicine and Biosciences, Airway Research Center North (ARCN), German Center for Lung Research, D-23845 Borstel, Germany
| | - Christina Schäffer
- Department of NanoBiotechnology, NanoGlycobiology unit, Universität für Bodenkultur Wien, Muthgasse 11, Austria
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45
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Yang XH, Huan LM, Chu XS, Sun Y, Shi QH. A comparative investigation of random and oriented immobilization of protein A ligands on the binding of immunoglobulin G. Biochem Eng J 2018. [DOI: 10.1016/j.bej.2018.08.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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46
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Ungewiß H, Rötzer V, Meir M, Fey C, Diefenbacher M, Schlegel N, Waschke J. Dsg2 via Src-mediated transactivation shapes EGFR signaling towards cell adhesion. Cell Mol Life Sci 2018; 75:4251-4268. [PMID: 29980799 PMCID: PMC11105603 DOI: 10.1007/s00018-018-2869-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 06/19/2018] [Accepted: 07/03/2018] [Indexed: 12/31/2022]
Abstract
Rapidly renewing epithelial tissues such as the intestinal epithelium require precise tuning of intercellular adhesion and proliferation to preserve barrier integrity. Here, we provide evidence that desmoglein 2 (Dsg2), an adhesion molecule of desmosomes, controls cell adhesion and proliferation via epidermal growth factor receptor (EGFR) signaling. Dsg2 is required for EGFR localization at intercellular junctions as well as for Src-mediated EGFR activation. Src binds to EGFR and is required for localization of EGFR and Dsg2 to cell-cell contacts. EGFR is critical for cell adhesion and barrier recovery. In line with this, Dsg2-deficient enterocytes display impaired barrier properties and increased cell proliferation. Mechanistically, Dsg2 directly interacts with EGFR and undergoes heterotypic-binding events on the surface of living enterocytes via its extracellular domain as revealed by atomic force microscopy. Thus, our study reveals a new mechanism by which Dsg2 via Src shapes EGFR function towards cell adhesion.
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Affiliation(s)
- Hanna Ungewiß
- Department I, Institute of Anatomy and Cell Biology, Ludwig Maximilians University Munich, Pettenkoferstr. 11, 80336, Munich, Germany
| | - Vera Rötzer
- Department I, Institute of Anatomy and Cell Biology, Ludwig Maximilians University Munich, Pettenkoferstr. 11, 80336, Munich, Germany
| | - Michael Meir
- Department of General, Visceral, Vascular and Paediatric Surgery, Julius-Maximilians-Universität, Oberdürrbacher Str. 6, 97080, Würzburg, Germany
| | - Christina Fey
- Department for Tissue Engineering and Regenerative Medicine, University Hospital Würzburg, Röntgenring 11, 97070, Würzburg, Germany
| | - Markus Diefenbacher
- Department of Biochemistry and Molecular Biochemistry, University of Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Nicolas Schlegel
- Department of General, Visceral, Vascular and Paediatric Surgery, Julius-Maximilians-Universität, Oberdürrbacher Str. 6, 97080, Würzburg, Germany
| | - Jens Waschke
- Department I, Institute of Anatomy and Cell Biology, Ludwig Maximilians University Munich, Pettenkoferstr. 11, 80336, Munich, Germany.
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47
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Molecular Recognition Force Spectroscopy for Probing Cell Targeted Nanoparticles In Vitro. Methods Mol Biol 2018. [PMID: 30374877 DOI: 10.1007/978-1-4939-8894-5_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
In the development and design of cell targeted nanoparticle-based systems the density of targeting moieties plays a fundamental role in allowing maximal cell-specific interaction. Here, we describe the use of molecular recognition force spectroscopy as a valuable tool for the characterization and optimization of targeted nanoparticles toward attaining cell-specific interaction. By tailoring the density of targeting moieties at the nanoparticle surface, one can correlate the unbinding event probability between nanoparticles tethered to an atomic force microscopy tip and cells to the nanoparticle vectoring capacity. This novel approach allows for a rapid and cost-effective design of targeted nanomedicines reducing the need for long and tedious in vitro tests.
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48
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Becke TD, Ness S, Sudhop S, Gaub HE, Hilleringmann M, Schilling AF, Clausen-Schaumann H. Covalent Immobilization of Proteins for the Single Molecule Force Spectroscopy. J Vis Exp 2018. [PMID: 30176022 PMCID: PMC6128213 DOI: 10.3791/58167] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
In recent years, atomic force microscopy (AFM) based single molecule force spectroscopy (SMFS) extended our understanding of molecular properties and functions. It gave us the opportunity to explore a multiplicity of biophysical mechanisms, e.g., how bacterial adhesins bind to host surface receptors in more detail. Among other factors, the success of SMFS experiments depends on the functional and native immobilization of the biomolecules of interest on solid surfaces and AFM tips. Here, we describe a straightforward protocol for the covalent coupling of proteins to silicon surfaces using silane-PEG-carboxyls and the well-established N-hydroxysuccinimid/1-ethyl-3-(3-dimethyl-aminopropyl)carbodiimid (EDC/NHS) chemistry in order to explore the interaction of pilus-1 adhesin RrgA from the Gram-positive bacterium Streptococcus pneumoniae (S. pneumoniae) with the extracellular matrix protein fibronectin (Fn). Our results show that the surface functionalization leads to a homogenous distribution of Fn on the glass surface and to an appropriate concentration of RrgA on the AFM cantilever tip, apparent by the target value of up to 20% of interaction events during SMFS measurements and revealed that RrgA binds to Fn with a mean force of 52 pN. The protocol can be adjusted to couple via site specific free thiol groups. This results in a predefined protein or molecule orientation and is suitable for other biophysical applications besides the SMFS.
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Affiliation(s)
- Tanja D Becke
- Center for Applied Tissue Engineering and Regenerative Medicine, Munich University of Applied Sciences; FG Protein Biochemistry & Cellular Microbiology, Munich University of Applied Sciences; Center for Nano Science, Ludwig-Maximilians-Universität München;
| | - Stefan Ness
- FG Protein Biochemistry & Cellular Microbiology, Munich University of Applied Sciences
| | - Stefanie Sudhop
- Center for Applied Tissue Engineering and Regenerative Medicine, Munich University of Applied Sciences; Center for Nano Science, Ludwig-Maximilians-Universität München
| | - Hermann E Gaub
- Center for Nano Science, Ludwig-Maximilians-Universität München
| | - Markus Hilleringmann
- FG Protein Biochemistry & Cellular Microbiology, Munich University of Applied Sciences
| | - Arndt F Schilling
- Klinik für Unfallchirurgie, Orthopädie und Plastische Chirurgie, University Medical Center Göttingen
| | - Hauke Clausen-Schaumann
- Center for Applied Tissue Engineering and Regenerative Medicine, Munich University of Applied Sciences; Center for Nano Science, Ludwig-Maximilians-Universität München
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49
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Optimization of a MT1-MMP-targeting Peptide and Its Application in Near-infrared Fluorescence Tumor Imaging. Sci Rep 2018; 8:10334. [PMID: 29985410 PMCID: PMC6037669 DOI: 10.1038/s41598-018-28493-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Accepted: 06/08/2018] [Indexed: 01/11/2023] Open
Abstract
Membrane type 1 metalloproteinase (MT1-MMP) is an important regulator of cancer invasion, growth and angiogenesis, thus making it an attractive target for cancer imaging and therapy. A non-substrate peptide (MT1-AF7p) that bonded to the "MT-Loop" region of MT1-MMP was identified by using a phage-displayed peptide library and was used to image the MT1-MMP expression in vivo through optical imaging. However, the substrate in the screening did not have a 3D structure, thus resulting in a loose bonding of MT1-AF7p. To simulate the real conformation of the "MT-Loop" and improve the performance of MT1-AF7p, molecular simulations were performed, because this strategy provides multiple methods for predicting the conformation and interaction of proteinase in 3D. In view of the binding site of the receptor-ligand interactions, histidine 4 was selected for mutation to achieve an increased affinity effect. The optimized peptides were further identified and conformed by atomic force microscopy, isothermal titration calorimetry, cell fluorescence imaging in vitro, and near-infrared fluorescence tumor optical imaging in vivo. The results revealed that the optimized peptide with a mutation of histidine 4 to arginine has the highest affinity and specificity, and exhibited an increased fluorescence intensity in the tumor site in optical imaging.
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50
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Vall-Sagarra A, Litau S, Decristoforo C, Wängler B, Schirrmacher R, Fricker G, Wängler C. Design, Synthesis, In Vitro, and Initial In Vivo Evaluation of Heterobivalent Peptidic Ligands Targeting Both NPY(Y₁)- and GRP-Receptors-An Improvement for Breast Cancer Imaging? Pharmaceuticals (Basel) 2018; 11:ph11030065. [PMID: 29973529 PMCID: PMC6161111 DOI: 10.3390/ph11030065] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 06/29/2018] [Accepted: 07/03/2018] [Indexed: 12/20/2022] Open
Abstract
Heterobivalent peptidic ligands (HBPLs), designed to address two different receptors independently, are highly promising tumor imaging agents. For example, breast cancer has been shown to concomitantly and complementarily overexpress the neuropeptide Y receptor subtype 1 (NPY(Y1)R) as well as the gastrin-releasing peptide receptor (GRPR). Thus, radiolabeled HBPLs being able to bind these two receptors should exhibit an improved tumor targeting efficiency compared to monospecific ligands. We developed here such bispecific HBPLs and radiolabeled them with 68Ga, achieving high radiochemical yields, purities, and molar activities. We evaluated the HBPLs and their monospecific reference peptides in vitro regarding stability and uptake into different breast cancer cell lines and found that the 68Ga-HBPLs were efficiently taken up via the GRPR. We also performed in vivo PET/CT imaging and ex vivo biodistribution studies in T-47D tumor-bearing mice for the most promising 68Ga-HBPL and compared the results to those obtained for its scrambled analogs. The tumors could easily be visualized by the newly developed 68Ga-HBPL and considerably higher tumor uptakes and tumor-to-background ratios were obtained compared to the scrambled analogs in and ex vivo. These results demonstrate the general feasibility of the approach to use bispecific radioligands for in vivo imaging of breast cancer.
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Affiliation(s)
- Alicia Vall-Sagarra
- Biomedical Chemistry, Department of Clinical Radiology and Nuclear Medicine, Medical Faculty Mannheim of Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany.
| | - Shanna Litau
- Biomedical Chemistry, Department of Clinical Radiology and Nuclear Medicine, Medical Faculty Mannheim of Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany.
- Molecular Imaging and Radiochemistry, Department of Clinical Radiology and Nuclear Medicine, Medical Faculty Mannheim of Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany.
| | - Clemens Decristoforo
- Department of Nuclear Medicine, University Hospital Innsbruck, Medical University Innsbruck, Anichstrasse 35, 6020 Innsbruck, Austria.
| | - Björn Wängler
- Molecular Imaging and Radiochemistry, Department of Clinical Radiology and Nuclear Medicine, Medical Faculty Mannheim of Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany.
| | - Ralf Schirrmacher
- Department of Oncology, Division Oncological Imaging, University of Alberta, 11560 University Avenue, Edmonton, AB T6G 1Z2, Canada.
| | - Gert Fricker
- Institute of Pharmacy and Molecular Biotechnology, University of Heidelberg, Im Neuenheimer Feld 329, 69120 Heidelberg, Germany.
| | - Carmen Wängler
- Biomedical Chemistry, Department of Clinical Radiology and Nuclear Medicine, Medical Faculty Mannheim of Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany.
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