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S100A6 Protein-Expression and Function in Norm and Pathology. Int J Mol Sci 2023; 24:ijms24021341. [PMID: 36674873 PMCID: PMC9866648 DOI: 10.3390/ijms24021341] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 01/03/2023] [Accepted: 01/06/2023] [Indexed: 01/13/2023] Open
Abstract
S100A6, also known as calcyclin, is a calcium-binding protein belonging to the S100 protein family. It was first identified and purified more than 30 years ago. Initial structural studies, focused mostly on the mode and affinity of Ca2+ binding and resolution of the resultant conformational changes, were soon complemented by research on its expression, localization and identification of binding partners. With time, the use of biophysical methods helped to resolve the structure and versatility of S100A6 complexes with some of its ligands. Meanwhile, it became clear that S100A6 expression was altered in various pathological states and correlated with the stage/progression of many diseases, including cancers, indicative of its important, and possibly causative, role in some of these diseases. This, in turn, prompted researchers to look for the mechanism of S100A6 action and to identify the intermediary signaling pathways and effectors. After all these years, our knowledge on various aspects of S100A6 biology is robust but still incomplete. The list of S100A6 ligands is growing all the time, as is our understanding of the physiological importance of these interactions. The present review summarizes available data concerning S100A6 expression/localization, interaction with intracellular and extracellular targets, involvement in Ca2+-dependent cellular processes and association with various pathologies.
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2
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He X, Zhang S, Dang D, Lin T, Ge Y, Chen X, Fan J. Detection of human annexin A1 as the novel N-terminal tag for separation and purification handle. Microb Cell Fact 2023; 22:2. [PMID: 36604649 PMCID: PMC9817314 DOI: 10.1186/s12934-022-02005-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 12/17/2022] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Several fusion tags for separation handle have been developed, but the fused tag for simply and cheaply separating the target protein is still lacking. RESULTS Separation conditions for the human annexin A1 (hanA1) tagged emerald green fluorescent protein (EmGFP) in Escherichia coli were optimized via precipitation with calcium chloride (CaCl2) and resolubilization with ethylenediamine tetraacetic acid disodium salt (EDTA-Na2). The HanA1-EmGFP absorbing with other three affinity matrix was detected, only it was strongly bound to heparin Sepharose. The separation efficiency of the HanA1-EmGFP was comparable with purification efficiency of the His6-tagged HanA1-EmGFP via metal ion affinity chromatography. Three fluorescent proteins for the EmGFP, mCherry red fluorescent protein and flavin-binding cyan-green fluorescent protein LOV from Chlamydomonas reinhardtii were used for naked-eye detection of the separation and purification processes, and two colored proteins including a red protein for a Vitreoscilla hemoglobin (Vhb), and a brown protein for maize sirohydrochlorin ferrochelatase (mSF) were used for visualizing the separation process. The added EDTA-Na2 disrupted the Fe-S cluster in the mSF, but it showed little impact on heme in Vhb. CONCLUSIONS The selected five colored proteins were efficient for detecting the applicability of the highly selective hanA1 for fusion separation and purification handle. The fused hanA1 tag will be potentially used for simple and cheap affinity separation of the target proteins in industry and diagnosis.
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Affiliation(s)
- Xiaomei He
- grid.460134.40000 0004 1757 393XCollege of Biological and Pharmaceutical Engineering, West Anhui University, Lu’an, 237012 People’s Republic of China ,grid.411389.60000 0004 1760 4804School of Life Science, Anhui, Anhui Agricultural University, 130, Changjiang West Road, Hefei, 230036 People’s Republic of China
| | - Shuncheng Zhang
- grid.411389.60000 0004 1760 4804School of Life Science, Anhui, Anhui Agricultural University, 130, Changjiang West Road, Hefei, 230036 People’s Republic of China
| | - Dongya Dang
- grid.411389.60000 0004 1760 4804School of Life Science, Anhui, Anhui Agricultural University, 130, Changjiang West Road, Hefei, 230036 People’s Republic of China
| | - Tingting Lin
- grid.411389.60000 0004 1760 4804School of Life Science, Anhui, Anhui Agricultural University, 130, Changjiang West Road, Hefei, 230036 People’s Republic of China
| | - Yuanyuan Ge
- grid.411389.60000 0004 1760 4804School of Life Science, Anhui, Anhui Agricultural University, 130, Changjiang West Road, Hefei, 230036 People’s Republic of China
| | - Xiaofeng Chen
- grid.411389.60000 0004 1760 4804School of Life Science, Anhui, Anhui Agricultural University, 130, Changjiang West Road, Hefei, 230036 People’s Republic of China
| | - Jun Fan
- grid.411389.60000 0004 1760 4804School of Life Science, Anhui, Anhui Agricultural University, 130, Changjiang West Road, Hefei, 230036 People’s Republic of China
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3
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Young BD, Cook ME, Costabile BK, Samanta R, Zhuang X, Sevdalis SE, Varney KM, Mancia F, Matysiak S, Lattman E, Weber DJ. Binding and Functional Folding (BFF): A Physiological Framework for Studying Biomolecular Interactions and Allostery. J Mol Biol 2022; 434:167872. [PMID: 36354074 PMCID: PMC10871162 DOI: 10.1016/j.jmb.2022.167872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 09/20/2022] [Accepted: 10/24/2022] [Indexed: 11/06/2022]
Abstract
EF-hand Ca2+-binding proteins (CBPs), such as S100 proteins (S100s) and calmodulin (CaM), are signaling proteins that undergo conformational changes upon increasing intracellular Ca2+. Upon binding Ca2+, S100 proteins and CaM interact with protein targets and induce important biological responses. The Ca2+-binding affinity of CaM and most S100s in the absence of target is weak (CaKD > 1 μM). However, upon effector protein binding, the Ca2+ affinity of these proteins increases via heterotropic allostery (CaKD < 1 μM). Because of the high number and micromolar concentrations of EF-hand CBPs in a cell, at any given time, allostery is required physiologically, allowing for (i) proper Ca2+ homeostasis and (ii) strict maintenance of Ca2+-signaling within a narrow dynamic range of free Ca2+ ion concentrations, [Ca2+]free. In this review, mechanisms of allostery are coalesced into an empirical "binding and functional folding (BFF)" physiological framework. At the molecular level, folding (F), binding and folding (BF), and BFF events include all atoms in the biomolecular complex under study. The BFF framework is introduced with two straightforward BFF types for proteins (type 1, concerted; type 2, stepwise) and considers how homologous and nonhomologous amino acid residues of CBPs and their effector protein(s) evolved to provide allosteric tightening of Ca2+ and simultaneously determine how specific and relatively promiscuous CBP-target complexes form as both are needed for proper cellular function.
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Affiliation(s)
- Brianna D Young
- The Center for Biomolecular Therapeutics (CBT), Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Mary E Cook
- The Center for Biomolecular Therapeutics (CBT), Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Brianna K Costabile
- Department of Physiology and Cellular Biophysics, Columbia University, New York, NY 10032, USA
| | - Riya Samanta
- Biophysics Graduate Program, University of Maryland, College Park, MD 20742, USA; Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA
| | - Xinhao Zhuang
- The Center for Biomolecular Therapeutics (CBT), Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Spiridon E Sevdalis
- The Center for Biomolecular Therapeutics (CBT), Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Kristen M Varney
- The Center for Biomolecular Therapeutics (CBT), Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Filippo Mancia
- Department of Physiology and Cellular Biophysics, Columbia University, New York, NY 10032, USA
| | - Silvina Matysiak
- Biophysics Graduate Program, University of Maryland, College Park, MD 20742, USA; Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA
| | - Eaton Lattman
- The Center for Biomolecular Therapeutics (CBT), Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; Department of Physics, Arizona State University, Tempe, AZ 85287, USA
| | - David J Weber
- The Center for Biomolecular Therapeutics (CBT), Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; The Institute of Bioscience and Biotechnology Research (IBBR), Rockville, MD 20850, USA.
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4
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Ashraf APK, Gerke V. The resealing factor S100A11 interacts with annexins and extended synaptotagmin-1 in the course of plasma membrane wound repair. Front Cell Dev Biol 2022; 10:968164. [PMID: 36200035 PMCID: PMC9527316 DOI: 10.3389/fcell.2022.968164] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 09/01/2022] [Indexed: 11/13/2022] Open
Abstract
After damage, cells repair their plasma membrane in an active process that is driven by Ca2+ entering through the wound. This triggers a range of Ca2+-regulated events such as the translocation of different Ca2+-binding proteins to the wound site which likely function in the repair process. The translocated proteins include Ca2+/phospholipid binding proteins of the annexin (ANX) family and S100A11, an EF hand-type Ca2+-binding protein which can interact with ANX. The molecular mechanism by which S100A11 mediates PM wound repair remains poorly understood although it likely involves interactions with ANX. Here, using S100A11 knockout endothelial cells and expression of S100A11 mutants, we show that endothelial S100A11 is essential for efficient plasma membrane wound repair and engages in Ca2+-dependent interactions with ANXA1 and ANXA2 through its C-terminal extension (residues 93–105). ANXA2 but not ANXA1 translocation to the wound is substantially inhibited in the absence of S100A11; however, the repair defect in S100A11 knockout cells is rescued by ectopic expression of an ANX interaction-defective S100A11 mutant, suggesting an ANX-independent role of S100A11 in membrane wound repair. In search for other interaction partners that could mediate this action of S100A11 we identify extended synaptotagmin 1 (E-Syt1), a protein tether that regulates endoplasmic reticulum-plasma membrane contact sites. E-Syt1 binds to S100A11 in the presence of Ca2+ and depletion of E-Syt1 interferes with wound site recruitment of S100A11 and proper membrane resealing. Thus, the role of S100A11 in membrane wound repair does not exclusively dependent on ANX interactions and a Ca2+-regulated S100A11-E-Syt1 complex acts as a yet unrecognized component of the membrane resealing machinery.
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Abstract
Some have hypothesized that ancestral proteins were, on average, less specific than their descendants. If true, this would provide a universal axis along which to organize protein evolution and suggests that reconstructed ancestral proteins may be uniquely powerful tools for protein engineering. Ancestral sequence reconstruction studies are one line of evidence used to support this hypothesis. Previously, we performed such a study, investigating the evolution of peptide-binding specificity for the paralogs S100A5 and S100A6. The modern proteins appeared more specific than their last common ancestor (ancA5/A6), as each paralog bound a subset of the peptides bound by ancA5/A6. In this study, we revisit this transition, using quantitative phage display to measure the interactions of 30,533 random peptides with human S100A5, S100A6, and ancA5/A6. This unbiased screen reveals a different picture. While S100A5 and S100A6 do indeed bind to a subset of the peptides recognized by ancA5/A6, they also acquired new peptide partners outside of the set recognized by ancA5/A6. Our previous work showed that ancA5/A6 had lower specificity than its descendants when measured against biological targets; our new work shows that ancA5/A6 has similar specificity to the modern proteins when measured against a random set of peptide targets. This demonstrates that altered biological specificity does not necessarily indicate altered intrinsic specificity, and sounds a cautionary note for using ancestral reconstruction studies with biological targets as a means to infer global evolutionary trends in specificity.
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Affiliation(s)
- Lucas C Wheeler
- Institute of Molecular Biology, University of Oregon, Eugene, OR, USA.,Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR, USA.,Department of Ecology and Evolutionary Biology, University of Colorado, Boulder, CO, USA
| | - Michael J Harms
- Institute of Molecular Biology, University of Oregon, Eugene, OR, USA.,Department of Chemistry and Biochemistry, University of Oregon, Eugene, OR, USA
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6
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Wheeler LC, Perkins A, Wong CE, Harms MJ. Learning peptide recognition rules for a low-specificity protein. Protein Sci 2020; 29:2259-2273. [PMID: 32979254 PMCID: PMC7586891 DOI: 10.1002/pro.3958] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 09/18/2020] [Accepted: 09/18/2020] [Indexed: 12/18/2022]
Abstract
Many proteins interact with short linear regions of target proteins. For some proteins, however, it is difficult to identify a well-defined sequence motif that defines its target peptides. To overcome this difficulty, we used supervised machine learning to train a model that treats each peptide as a collection of easily-calculated biochemical features rather than as an amino acid sequence. As a test case, we dissected the peptide-recognition rules for human S100A5 (hA5), a low-specificity calcium binding protein. We trained a Random Forest model against a recently released, high-throughput phage display dataset collected for hA5. The model identifies hydrophobicity and shape complementarity, rather than polar contacts, as the primary determinants of peptide binding specificity in hA5. We tested this hypothesis by solving a crystal structure of hA5 and through computational docking studies of diverse peptides onto hA5. These structural studies revealed that peptides exhibit multiple binding modes at the hA5 peptide interface-all of which have few polar contacts with hA5. Finally, we used our trained model to predict new, plausible binding targets in the human proteome. This revealed a fragment of the protein α-1-syntrophin that binds to hA5. Our work helps better understand the biochemistry and biology of hA5, as well as demonstrating how high-throughput experiments coupled with machine learning of biochemical features can reveal the determinants of binding specificity in low-specificity proteins.
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Affiliation(s)
- Lucas C. Wheeler
- Institute of Molecular BiologyUniversity of OregonEugeneOregonUSA
- Department of Chemistry and BiochemistryUniversity of OregonEugeneOregonUSA
- Department of Ecology and Evolutionary BiologyUniversity of ColoradoBoulderColoradoUSA
| | - Arden Perkins
- Institute of Molecular BiologyUniversity of OregonEugeneOregonUSA
- Department of Chemistry and BiochemistryUniversity of OregonEugeneOregonUSA
| | - Caitlyn E. Wong
- Institute of Molecular BiologyUniversity of OregonEugeneOregonUSA
- Department of Chemistry and BiochemistryUniversity of OregonEugeneOregonUSA
| | - Michael J. Harms
- Institute of Molecular BiologyUniversity of OregonEugeneOregonUSA
- Department of Chemistry and BiochemistryUniversity of OregonEugeneOregonUSA
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7
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Expression of S100 proteins is associated with HBV intrauterine transmission. Arch Gynecol Obstet 2020; 302:1389-1399. [PMID: 32856138 DOI: 10.1007/s00404-020-05753-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 08/15/2020] [Indexed: 12/26/2022]
Abstract
PURPOSE The mechanisms underlying HBV intrauterine transmission remain unknown. In this study, we explored the mechanism of HBV intrauterine transmission by iTRAQ proteomics analysis. METHODS iTRAQ technology was applied to perform comparative proteomics studies on six HBV+/+ neonates and six HBV+/- neonates whose mothers and fathers were HBsAg positive and paternal HBsAg negative, respectively. The data obtained from the mass spectrometer were analyzed using MASCOT ( https://matrixscience.com ) to qualitatively and quantitatively compare the differentially expressed proteins in the two groups. Gene Ontology and KEGG pathway analyses were performed to analyze the differentially expressed proteins. The expressions of HBV intrauterine transmission-related proteins in serum samples and corresponding placental tissues were further verified by immunohistochemistry and Western Blot. Then, the human trophoblast cell line (Swan71) infected with HBV was used to analyze the potential mechanisms of HBV intrauterine transmission under the mediation of differential proteins. RESULTS A total of 35 differentially expressed proteins, including 17 up-regulated proteins and 18 down-regulated proteins, were identified by comparing serum protein expression levels in HBV+/+ and HBV+/- neonates. The differentially expressed proteins were mainly related to RAGE receptor binding, NF-kappa B transcription factor activity, innate immune response, defense response to bacterium, and the signaling pathway in pathogenic microorganism infection. The expressions of S100A8/9/12 in HBV+/+ maternal placenta tissue were significantly increased. The expressions of S100A8/9/12 proteins in Swan71 cells were significantly increased after HBV infection. CONCLUSION High expression of S100 proteins may be associated with the intrauterine-transplacental transmission of HBV.
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8
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Simon MA, Ecsédi P, Kovács GM, Póti ÁL, Reményi A, Kardos J, Gógl G, Nyitray L. High-throughput competitive fluorescence polarization assay reveals functional redundancy in the S100 protein family. FEBS J 2020; 287:2834-2846. [PMID: 31837246 DOI: 10.1111/febs.15175] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 11/02/2019] [Accepted: 12/10/2019] [Indexed: 12/26/2022]
Abstract
The calcium-binding, vertebrate-specific S100 protein family consists of 20 paralogs in humans (referred as the S100ome), with several clinically important members. To explore their protein-protein interactions (PPIs) quantitatively, we have chosen an unbiased, high-throughput, competitive fluorescence polarization (FP) assay that revealed a partial functional redundancy when the complete S100ome (n = 20) was tested against numerous model partners (n = 13). Based on their specificity, the S100ome can be grouped into two distinct classes: promiscuous and orphan. In the first group, members bound to several ligands (> 4-5) with comparable high affinity, while in the second one, the paralogs bound only one partner weakly, or no ligand was identified. Our results demonstrate that FP assays are highly suitable for quantitative interaction profiling of selected protein families. Moreover, we provide evidence that PPI-based phenotypic characterization can complement or even exceed the information obtained from the sequence-based phylogenetic analysis of the S100ome, an evolutionary young protein family.
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Affiliation(s)
- Márton A Simon
- Department of Biochemistry, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Péter Ecsédi
- Department of Biochemistry, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Gábor M Kovács
- Department of Plant Anatomy, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Ádám L Póti
- Institute of Organic Chemistry, Research Center for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - Attila Reményi
- Institute of Organic Chemistry, Research Center for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - József Kardos
- Department of Biochemistry, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Gergő Gógl
- Department of Biochemistry, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary.,Equipe Labellisee Ligue 2015, Department of Integrated Structural Biology, Institut de Genetique et de Biologie Moleculaire et Cellulaire (IGBMC), INSERM U1258, CNRS UMR 7104, Universite de Strasbourg, Illkirch, France
| | - László Nyitray
- Department of Biochemistry, Institute of Biology, ELTE Eötvös Loránd University, Budapest, Hungary
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9
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Yan X, Lebel-Beaucage MF, Tremblay S, Cantin L, Shaw GS, Boisselier E. Optimized transformation, overexpression and purification of S100A10. Biotechniques 2019; 67:246-248. [DOI: 10.2144/btn-2019-0081] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
As a member of the S100 protein family, S100A10 has already been purified. However, its purity, or even yield, have often not been reported in the literature. To facilitate future biophysical experiments with S100A10, we aimed to obtain it at a purity of at least 95% in a reasonably large amount. Here, we report optimized conditions for the transformation, overexpression and purification of the protein. We obtained a purity of 97% and performed stability studies by circular dichroism. Our data confirmed that the S100A10 obtained is suitable for experiments to be performed at room temperature up to several days.
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Affiliation(s)
- Xiaolin Yan
- Department of Ophthalmology, Faculty of Medicine, Université Laval, Quebec, QC, Canada
- CUO–Recherche, Centre de Recherche du CHU de Québec, Hôpital du Saint-Sacrement, CHU de Québec, Quebec, QC, Canada
| | - Marie-France Lebel-Beaucage
- Departement of Chemistry, Biochemistry & Physics, Faculty of Sciences, Université du Québec à Trois-Rivières, Quebec, QC, Canada
| | - Samuel Tremblay
- Department of Ophthalmology, Faculty of Medicine, Université Laval, Quebec, QC, Canada
- CUO–Recherche, Centre de Recherche du CHU de Québec, Hôpital du Saint-Sacrement, CHU de Québec, Quebec, QC, Canada
| | - Line Cantin
- Department of Ophthalmology, Faculty of Medicine, Université Laval, Quebec, QC, Canada
- CUO–Recherche, Centre de Recherche du CHU de Québec, Hôpital du Saint-Sacrement, CHU de Québec, Quebec, QC, Canada
| | - Gary S Shaw
- Departement of Biochemistry, Schulich School of Medicine & Dentistry, University of Western Ontario, London, ON, Canada
| | - Elodie Boisselier
- Department of Ophthalmology, Faculty of Medicine, Université Laval, Quebec, QC, Canada
- CUO–Recherche, Centre de Recherche du CHU de Québec, Hôpital du Saint-Sacrement, CHU de Québec, Quebec, QC, Canada
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10
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Singhto N, Thongboonkerd V. Exosomes derived from calcium oxalate-exposed macrophages enhance IL-8 production from renal cells, neutrophil migration and crystal invasion through extracellular matrix. J Proteomics 2018; 185:64-76. [DOI: 10.1016/j.jprot.2018.06.015] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 06/06/2018] [Accepted: 06/18/2018] [Indexed: 12/11/2022]
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Xia Q, Li X, Zhou H, Zheng L, Shi J. S100A11 protects against neuronal cell apoptosis induced by cerebral ischemia via inhibiting the nuclear translocation of annexin A1. Cell Death Dis 2018; 9:657. [PMID: 29844306 PMCID: PMC5974363 DOI: 10.1038/s41419-018-0686-7] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 05/07/2018] [Accepted: 05/09/2018] [Indexed: 12/17/2022]
Abstract
The subcellular location of annexin A1 (ANXA1) determines the ultimate fate of neurons after ischemic stroke. ANXA1 nuclear translocation is involved in neuronal apoptosis after cerebral ischemia, and extracellular ANXA1 is also associated with regulation of inflammatory responses. As the factors and mechanism that influence ANXA1 subcellular translocation remain unclear, studies aiming to determine and clarify the role of ANXA1 as a cell fate ‘regulator’ within cells are critically needed. In this study, we found that intracerebroventricular injection of the recombinant adenovirus vector Ad-S100A11 (carrying S100A11) strongly improved cognitive function and induced robust neuroprotective effects after ischemic stroke in vivo. Furthermore, upregulation of S100A11 protected against neuronal apoptosis induced by oxygen-glucose deprivation and reoxygenation (OGD/R) in vitro. Surprisingly, S100A11 overexpression markedly decreased ANXA1 nuclear translocation and subsequently alleviated OGD/R-induced neuronal apoptosis. Notably, S100A11 exerted its neuroprotective effect by directly binding ANXA1. Importantly, S100A11 directly interacted with ANXA1 through the nuclear translocation signal (NTS) of ANXA1, which is essential for ANXA1 to import into the nucleus. Consistent with our previous studies, ANXA1 nuclear translocation after OGD/R promoted p53 transcriptional activity, induced mRNA expression of the pro-apoptotic Bid gene, and activated the caspase-3 apoptotic pathway, which was almost completely reversed by S100A11 overexpression. Thus, S100A11 protects against cell apoptosis by inhibiting OGD/R-induced ANXA1 nuclear translocation. This study provides a novel mechanism whereby S100A11 protects against neuronal cells apoptosis, suggesting the potential for a previously unidentified treatment strategy in minimizing apoptosis after ischemic stroke.
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Affiliation(s)
- Qian Xia
- Department of Neurobiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China.,Key Laboratory of Neurological Diseases, Ministry of Education, Wuhan, People's Republic of China.,Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - Xing Li
- Department of Neurobiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China.,Key Laboratory of Neurological Diseases, Ministry of Education, Wuhan, People's Republic of China.,Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - Huijuan Zhou
- Department of Neurobiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China.,Key Laboratory of Neurological Diseases, Ministry of Education, Wuhan, People's Republic of China.,Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - Lu Zheng
- Department of Neurobiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China.,Key Laboratory of Neurological Diseases, Ministry of Education, Wuhan, People's Republic of China.,Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, People's Republic of China
| | - Jing Shi
- Department of Neurobiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, People's Republic of China. .,Key Laboratory of Neurological Diseases, Ministry of Education, Wuhan, People's Republic of China. .,Institute for Brain Research, Collaborative Innovation Center for Brain Science, Huazhong University of Science and Technology, Wuhan, People's Republic of China.
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12
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Wheeler LC, Anderson JA, Morrison AJ, Wong CE, Harms MJ. Conservation of Specificity in Two Low-Specificity Proteins. Biochemistry 2017; 57:684-695. [PMID: 29240404 DOI: 10.1021/acs.biochem.7b01086] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Many regulatory proteins bind peptide regions of target proteins and modulate their activity. Such regulatory proteins can often interact with highly diverse target peptides. In many instances, it is not known if the peptide-binding interface discriminates targets in a biological context, or whether biological specificity is achieved exclusively through external factors such as subcellular localization. We used an evolutionary biochemical approach to distinguish these possibilities for two such low-specificity proteins: S100A5 and S100A6. We used isothermal titration calorimetry to study the binding of peptides with diverse sequence and biochemistry to human S100A5 and S100A6. These proteins bound distinct, but overlapping, sets of peptide targets. We then studied the peptide binding properties of orthologs sampled from across five amniote species. Binding specificity was conserved along all lineages, for the last 320 million years, despite the low specificity of each protein. We used ancestral sequence reconstruction to determine the binding specificity of the last common ancestor of the paralogs. The ancestor bound the entire set of peptides bound by modern S100A5 and S100A6 proteins, suggesting that paralog specificity evolved via subfunctionalization. To rule out the possibility that specificity is conserved because it is difficult to modify, we identified a single historical mutation that, when reverted in human S100A5, gave it the ability to bind an S100A6-specific peptide. These results reveal strong evolutionary constraints on peptide binding specificity. Despite being able to bind a large number of targets, the specificity of S100 peptide interfaces is likely important for the biology of these proteins.
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Affiliation(s)
- Lucas C Wheeler
- Department of Chemistry and Biochemistry, University of Oregon , Eugene, Oregon 97403, United States.,Institute of Molecular Biology, University of Oregon , Eugene, Oregon 97403, United States
| | - Jeremy A Anderson
- Department of Chemistry and Biochemistry, University of Oregon , Eugene, Oregon 97403, United States.,Institute of Molecular Biology, University of Oregon , Eugene, Oregon 97403, United States
| | - Anneliese J Morrison
- Department of Chemistry and Biochemistry, University of Oregon , Eugene, Oregon 97403, United States.,Institute of Molecular Biology, University of Oregon , Eugene, Oregon 97403, United States
| | - Caitlyn E Wong
- Department of Chemistry and Biochemistry, University of Oregon , Eugene, Oregon 97403, United States.,Institute of Molecular Biology, University of Oregon , Eugene, Oregon 97403, United States
| | - Michael J Harms
- Department of Chemistry and Biochemistry, University of Oregon , Eugene, Oregon 97403, United States.,Institute of Molecular Biology, University of Oregon , Eugene, Oregon 97403, United States
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13
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Regulation of the Equilibrium between Closed and Open Conformations of Annexin A2 by N-Terminal Phosphorylation and S100A4-Binding. Structure 2017; 25:1195-1207.e5. [PMID: 28669632 DOI: 10.1016/j.str.2017.06.001] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 04/27/2017] [Accepted: 06/01/2017] [Indexed: 11/20/2022]
Abstract
Annexin A2 (ANXA2) has a versatile role in membrane-associated functions including membrane aggregation, endo- and exocytosis, and it is regulated by post-translational modifications and protein-protein interactions through the unstructured N-terminal domain (NTD). Our sequence analysis revealed a short motif responsible for clamping the NTD to the C-terminal core domain (CTD). Structural studies indicated that the flexibility of the NTD and CTD are interrelated and oppositely regulated by Tyr24 phosphorylation and Ser26Glu phosphomimicking mutation. The crystal structure of the ANXA2-S100A4 complex showed that asymmetric binding of S100A4 induces dislocation of the NTD from the CTD and, similar to the Ser26Glu mutation, unmasks the concave side of ANXA2. In contrast, pTyr24 anchors the NTD to the CTD and hampers the membrane-bridging function. This inhibition can be restored by S100A4 and S100A10 binding. Based on our results we provide a structural model for regulation of ANXA2-mediated membrane aggregation by NTD phosphorylation and S100 binding.
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14
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Biri-Kovács B, Kiss B, Vadászi H, Gógl G, Pálfy G, Török G, Homolya L, Bodor A, Nyitray L. Ezrin interacts with S100A4 via both its N- and C-terminal domains. PLoS One 2017; 12:e0177489. [PMID: 28493957 PMCID: PMC5426754 DOI: 10.1371/journal.pone.0177489] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2017] [Accepted: 04/27/2017] [Indexed: 11/19/2022] Open
Abstract
Ezrin belongs to the ERM (ezrin, radixin, moesin) protein family that has a role in cell morphology changes, adhesion and migration as an organizer of the cortical cytoskeleton by linking actin filaments to the apical membrane of epithelial cells. It is highly expressed in a variety of human cancers and promotes metastasis. Members of the Ca2+-binding EF-hand containing S100 proteins have similar pathological properties; they are overexpressed in cancer cells and involved in metastatic processes. In this study, using tryptophan fluorescence and stopped-flow kinetics, we show that S100A4 binds to the N-terminal ERM domain (N-ERMAD) of ezrin with a micromolar affinity. The binding involves the F2 lobe of the N-ERMAD and follows an induced fit kinetic mechanism. Interestingly, S100A4 binds also to the unstructured C-terminal actin binding domain (C-ERMAD) with similar affinity. Using NMR spectroscopy, we characterized the complex of S100A4 with the C-ERMAD and demonstrate that no ternary complex is simultaneously formed with the two ezrin domains. Furthermore, we show that S100A4 co-localizes with ezrin in HEK-293T cells. However, S100A4 very weakly binds to full-length ezrin in vitro indicating that the interaction of S100A4 with ezrin requires other regulatory events such as protein phosphorylation and/or membrane binding, shifting the conformational equilibrium of ezrin towards the open state. As both proteins play an important role in promoting metastasis, the characterization of their interaction could shed more light on the molecular events contributing to this pathological process.
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Affiliation(s)
- Beáta Biri-Kovács
- Department of Biochemistry, Eötvös Loránd University, Budapest, Hungary
| | - Bence Kiss
- Department of Biochemistry, Eötvös Loránd University, Budapest, Hungary
| | - Henrietta Vadászi
- Department of Biochemistry, Eötvös Loránd University, Budapest, Hungary
| | - Gergő Gógl
- Department of Biochemistry, Eötvös Loránd University, Budapest, Hungary
| | - Gyula Pálfy
- Institute of Chemistry, Laboratory of Structural Chemistry and Biology, Eötvös Loránd University, Budapest, Hungary
| | - György Török
- Molecular Cell Biology Research Group, Institute of Enzymology, Research Centre for Natural Sciences, Budapest, Hungary
| | - László Homolya
- Molecular Cell Biology Research Group, Institute of Enzymology, Research Centre for Natural Sciences, Budapest, Hungary
| | - Andrea Bodor
- Institute of Chemistry, Laboratory of Structural Chemistry and Biology, Eötvös Loránd University, Budapest, Hungary
| | - László Nyitray
- Department of Biochemistry, Eötvös Loránd University, Budapest, Hungary
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15
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Abstract
Influenza A virus (IAV) is a serious global health problem worldwide due to frequent and severe outbreaks. IAV causes significant morbidity and mortality in the elderly population, due to the ineffectiveness of the vaccine and the alteration of T cell immunity with ageing. The cellular and molecular link between ageing and virus infection is unclear and it is possible that damage associated molecular patterns (DAMPs) may play a role in the raised severity and susceptibility of virus infections in the elderly. DAMPs which are released from damaged cells following activation, injury or cell death can activate the immune response through the stimulation of the inflammasome through several types of receptors found on the plasma membrane, inside endosomes after endocytosis as well as in the cytosol. In this review, the detriment in the immune system during ageing and the links between influenza virus infection and ageing will be discussed. In addition, the role of DAMPs such as HMGB1 and S100/Annexin in ageing, and the enhanced morbidity and mortality to severe influenza infection in ageing will be highlighted.
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16
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Liu Y, Myrvang HK, Dekker LV. Annexin A2 complexes with S100 proteins: structure, function and pharmacological manipulation. Br J Pharmacol 2014; 172:1664-76. [PMID: 25303710 PMCID: PMC4376447 DOI: 10.1111/bph.12978] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Revised: 09/16/2014] [Accepted: 10/05/2014] [Indexed: 12/13/2022] Open
Abstract
Annexin A2 (AnxA2) was originally identified as a substrate of the pp60v-src oncoprotein in transformed chicken embryonic fibroblasts. It is an abundant protein that associates with biological membranes as well as the actin cytoskeleton, and has been implicated in intracellular vesicle fusion, the organization of membrane domains, lipid rafts and membrane-cytoskeleton contacts. In addition to an intracellular role, AnxA2 has been reported to participate in processes localized to the cell surface including extracellular protease regulation and cell-cell interactions. There are many reports showing that AnxA2 is differentially expressed between normal and malignant tissue and potentially involved in tumour progression. An important aspect of AnxA2 function relates to its interaction with small Ca2+-dependent adaptor proteins called S100 proteins, which is the topic of this review. The interaction between AnxA2 and S100A10 has been very well characterized historically; more recently, other S100 proteins have been shown to interact with AnxA2 as well. The biochemical evidence for the occurrence of these protein interactions will be discussed, as well as their function. Recent studies aiming to generate inhibitors of S100 protein interactions will be described and the potential of these inhibitors to further our understanding of AnxA2 S100 protein interactions will be discussed.
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Affiliation(s)
- Yidong Liu
- School of Pharmacy, Centre for Biomolecular Sciences, University of Nottingham, Nottingham, UK
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17
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Cai ZK, Chen Q, Chen YB, Gu M, Zheng DC, Zhou J, Wang Z. microRNA-155 promotes the proliferation of prostate cancer cells by targeting annexin 7. Mol Med Rep 2014; 11:533-8. [PMID: 25339368 DOI: 10.3892/mmr.2014.2744] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Accepted: 06/26/2014] [Indexed: 11/06/2022] Open
Abstract
Micro (mi)RNAs are a group of small non-coding RNA molecules that have been demonstrated to regulate the expression of genes involved in tumorigenesis. The relevance of microRNAs in the development, progression and prognosis of prostate cancer is not fully understood. miR-155 has been implicated in the induction of breast, lung and liver cancer, but its role in prostate cancer has not been investigated. In the present study, the biological function of miR-155 was investigated in prostate cancer for the first time, to the best of our knowledge. It was demonstrated that the expression of miR-155 was upregulated in prostate cancer tissues and cell lines as determined by quantitative reverse transcription-polymerase chain reaction. Furthermore, overexpression of miR-155 promoted cell proliferation, as indicated by MTT assay. Flow cytometric analysis demonstrated that inhibition of miR-155 induced cell cycle arrest and promoted apoptosis in prostate cancer cells. In addition, western blot analysis indicated that annexin (ANX)7 was significantly downregulated in prostate cancer tissues and cells. A luciferase reporter assay indicated that ANX7 was a target of miR-155, which suggested that miRNA-155 promoted the proliferation of prostate cancer cells by regulating ANX7 expression levels.
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Affiliation(s)
- Zhi-Kang Cai
- Department of Urology and Andrology, Ninth People's Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200011, P.R. China
| | - Qi Chen
- Department of Urology and Andrology, Ninth People's Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200011, P.R. China
| | - Yan-Bo Chen
- Department of Urology and Andrology, Ninth People's Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200011, P.R. China
| | - Meng Gu
- Department of Urology and Andrology, Ninth People's Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200011, P.R. China
| | - Da-Chao Zheng
- Department of Urology and Andrology, Ninth People's Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200011, P.R. China
| | - Juan Zhou
- Department of Urology and Andrology, Ninth People's Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200011, P.R. China
| | - Zhong Wang
- Department of Urology and Andrology, Ninth People's Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai 200011, P.R. China
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18
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Gravius S, Randau TM, Casadonte R, Kriegsmann M, Friedrich MJ, Kriegsmann J. Investigation of neutrophilic peptides in periprosthetic tissue by matrix-assisted laser desorption ionisation time-of-flight imaging mass spectrometry. INTERNATIONAL ORTHOPAEDICS 2014; 39:559-67. [PMID: 25277763 DOI: 10.1007/s00264-014-2544-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2014] [Accepted: 09/17/2014] [Indexed: 01/11/2023]
Abstract
PURPOSE The accurate diagnosis of periprosthetic joint infection (PJI) relies on clinical investigation, laboratory parameters, radiological methods, sterile joint aspiration for synovial fluid leucocyte count and microbiological analysis and tissue sampling for histopathology. Due to the limits in specificity and sensitivity of these methods, molecular techniques and new biomarkers were introduced into the diagnostic procedure. Histological examination is related to the amount of neutrophils in the periprosthetic tissue in frozen sections and formalin-fixed paraffin embedded material (FFPE). However, the threshold of neutrophils per defined area of tissue among various studies is very inconsistent. METHODS We have applied matrix-assisted laser desorption ionisation time-of-flight imaging mass spectrometry (MALDI IMS) to a total of 32 periprosthetic tissue samples of patients with PJI to detect peptides associated with areas of neutrophil infiltration. RESULTS Specific peaks associated with a high amount of neutrophils were detected. Of these m/z peaks, four could be assigned to predictive neutrophil molecules. These peptides include annexin A1, calgizzarin (S100A11), calgranulin C (S100A12) and histone H2A. By MALDI IMS, these peptides could be shown to be co-localised with the infiltration of neutrophils in the immediate vicinity of the periprosthetic interface, whereas more distant areas did not show neutrophil invasion or infection-related peptides. CONCLUSIONS MALDI IMS is a new method allowing identification of neutrophil peptides in periprosthetic tissues and may be a surrogate for counting neutrophils as an objective parameter for PJI.
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Affiliation(s)
- Sascha Gravius
- Department of Orthopedics and Trauma Surgery, University Clinic of Bonn, Sigmund Freud Str. 25, 53105, Bonn, Germany,
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19
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Wafer LN, Tzul FO, Pandharipande PP, McCallum SA, Makhatadze GI. Structural and thermodynamic characterization of the recognition of the S100-binding peptides TRTK12 and p53 by calmodulin. Protein Sci 2014; 23:1247-61. [PMID: 24947426 DOI: 10.1002/pro.2506] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Revised: 06/14/2014] [Accepted: 06/17/2014] [Indexed: 11/07/2022]
Abstract
Calmodulin (CaM) is a multifunctional messenger protein that activates a wide variety of signaling pathways in eukaryotic cells in a calcium-dependent manner. CaM has been proposed to be functionally distinct from the S100 proteins, a related family of eukaryotic calcium-binding proteins. Previously, it was demonstrated that peptides derived from the actin-capping protein, TRTK12, and the tumor-suppressor protein, p53, interact with multiple members of the S100 proteins. To test the specificity of these peptides, they were screened using isothermal titration calorimetry against 16 members of the human S100 protein family, as well as CaM, which served as a negative control. Interestingly, both the TRTK12 and p53 peptides were found to interact with CaM. These interactions were further confirmed by both fluorescence and nuclear magnetic resonance spectroscopies. These peptides have distinct sequences from the known CaM target sequences. The TRTK12 peptide was found to independently interact with both CaM domains and bind with a stoichiometry of 2:1 and dissociations constants Kd,C-term = 2 ± 1 µM and Kd,N-term = 14 ± 1 µM. In contrast, the p53 peptide was found to interact only with the C-terminal domain of CaM, Kd,C-term = 2 ± 1 µM, 25°C. Using NMR spectroscopy, the locations of the peptide binding sites were mapped onto the structure of CaM. The binding sites for both peptides were found to overlap with the binding interface for previously identified targets on both domains of CaM. This study demonstrates the plasticity of CaM in target binding and may suggest a possible overlap in target specificity between CaM and the S100 proteins.
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Affiliation(s)
- Lucas N Wafer
- Department of Biological Sciences, Rensselaer Polytechnic Institute, Troy, New York, 12180; Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York, 12180
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20
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Wafer LN, Tzul FO, Pandharipande PP, Makhatadze GI. Novel interactions of the TRTK12 peptide with S100 protein family members: specificity and thermodynamic characterization. Biochemistry 2013; 52:5844-56. [PMID: 23899389 DOI: 10.1021/bi400788s] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The S100 protein family consists of small, dimeric proteins that exert their biological functions in response to changing calcium concentrations. S100B is the best-studied member and has been shown to interact with more than 20 binding partners in a calcium-dependent manner. The TRTK12 peptide, derived from the consensus binding sequence for S100B, has previously been found to interact with S100A1 and has been proposed to be a general binding partner of the S100 family. To test this hypothesis and gain a better understanding of the specificity of binding for the S100 proteins, 16 members of the human S100 family were screened against this peptide and its alanine variants. Novel interactions were found with only two family members, S100P and S100A2, indicating that TRTK12 selectively interacts with a small subset of the S100 proteins. Substantial promiscuity was observed in the binding site of S100B thereby accommodating variations in the peptide sequence, while S100A1, S100A2, and S100P exhibited larger differences in the binding constants for the TRTK12 alanine variants. This suggests that single-point substitutions can be used to selectively modulate the affinity of TRTK12 peptides for individual S100 proteins. This study has important implications for the rational drug design of inhibitors for the S100 proteins, which are involved in a variety of cancers and neurodegenerative diseases.
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Affiliation(s)
- Lucas N Wafer
- Department of Biology, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, New York 12180, United States
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21
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Ca(2+)-binding protein expression in primary human thyrocytes. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2013; 1833:2703-2713. [PMID: 23886630 DOI: 10.1016/j.bbamcr.2013.07.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Revised: 06/04/2013] [Accepted: 07/15/2013] [Indexed: 01/06/2023]
Abstract
We recently identified several Ca(2+)-binding proteins (CaBP) from the S100 and annexin family to be regulated by TSH in FRTL-5 cells. Here, we study the regulation of S100A4, S100A6 and ANXA2 in primary human thyrocytes (PHT) derived from surrounding tissues (ST), cold benign thyroid nodules (CTN) and autonomously functioning thyroid nodules (AFTN). We investigated the expression and regulation of CaBP and the effect of their expression on Ca(2+) and TSHR signaling. We used an approach that accounts for the potential of an individual PHT culture to proliferate or to express thyroid differentiation features by assessing the expression of FOS and TPO. We found a strong correlation between the regulation of CaBP and the proliferation-associated transcription factor gene FOS. PKA and MEK1/2 were regulators of ANXA2 expression, while PI3-K and triiodothyronine were additionally involved in S100 regulation. The modulated expression of CaBP was reflected by changes in ATP-elicited Ca(2+) signaling in PHT. S100A4 increased the ratio of subsequent Ca(2+) responses and showed a Ca(2+) buffering effect, while ANXA2 affected the first Ca(2+) response to ATP. Overexpression of S100A4 led to a reduced activation of NFAT by TSH. Using S100A4 E33Q, D63N, F72Q and Y75K mutants we found that the effects of S100A4 expression on Ca(2+) signaling are mediated by protein interaction. We present evidence that TSH has the ability to fine-tune Ca(2+) signals through the regulation of CaBP expression. This represents a novel putative cross-regulating mechanism in thyrocytes that could affect thyrocyte signaling and physiology.
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22
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Wang F, Wang L, Xu Z, Liang G. Identification and analysis of multi-protein complexes in placenta. PLoS One 2013; 8:e62988. [PMID: 23638173 PMCID: PMC3639281 DOI: 10.1371/journal.pone.0062988] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Accepted: 03/27/2013] [Indexed: 12/13/2022] Open
Abstract
Placental malfunction induces pregnancy disorders which contribute to life-threatening complications for both the mother and the fetus. Identification and characterization of placental multi-protein complexes is an important step to integratedly understand the protein-protein interaction networks in placenta which determine placental function. In this study, blue native/sodium dodecyl sulfate polyacrylamide gel electrophoresis (BN/SDS-PAGE) and Liquid chromatography-tandem mass spectrometry (LC-MS/MS) were used to screen the multi-protein complexes in placenta. 733 unique proteins and 34 known and novel heterooligomeric multi-protein complexes including mitochondrial respiratory chain complexes, integrin complexes, proteasome complexes, histone complex, and heat shock protein complexes were identified. A novel protein complex, which involves clathrin and small conductance calcium-activated potassium (SK) channel protein 2, was identified and validated by antibody based gel shift assay, co-immunoprecipitation and immunofluorescence staining. These results suggest that BN/SDS-PAGE, when integrated with LC-MS/MS, is a very powerful and versatile tool for the investigation of placental protein complexes. This work paves the way for deeper functional characterization of the placental protein complexes associated with pregnancy disorders.
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Affiliation(s)
- Fuqiang Wang
- CAS Key Laboratory of Soft Matter Chemistry, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui, China
- State Key Laboratory of Reproductive Medicine, Analysis Center, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Ling Wang
- State Key Laboratory of Reproductive Medicine, Analysis Center, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Zhiyang Xu
- State Key Laboratory of Reproductive Medicine, Analysis Center, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Gaolin Liang
- CAS Key Laboratory of Soft Matter Chemistry, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui, China
- * E-mail:
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23
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Yoshimura C, Miyafusa T, Tsumoto K. Identification of small-molecule inhibitors of the human S100B-p53 interaction and evaluation of their activity in human melanoma cells. Bioorg Med Chem 2013; 21:1109-15. [PMID: 23375094 DOI: 10.1016/j.bmc.2012.12.042] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2012] [Revised: 12/31/2012] [Accepted: 12/31/2012] [Indexed: 10/27/2022]
Abstract
The interaction between human S100 calcium-binding protein B (S100B) and the tumor suppressor protein p53 is considered to be a possible therapeutic target for malignant melanoma. To identify potent inhibitors of this interaction, we screened a fragment library of compounds by means of a fluorescence-based competition assay involving the S100B-binding C-terminal peptide of p53. Using active compounds from the fragment library as query compounds, we constructed a focused library by means of two-dimensional similarity searching of a large database. This simple, unbiased method allowed us to identify several inhibitors of the S100B-p53 interaction, and we elucidated preliminary structure-activity relationships. One of the identified compounds had the potential to inhibit the S100B-p53 interaction in melanoma cells.
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Affiliation(s)
- Chihoko Yoshimura
- Medical Proteomics Laboratory, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
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24
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Wafer LN, Streicher WW, McCallum SA, Makhatadze GI. Thermodynamic and kinetic analysis of peptides derived from CapZ, NDR, p53, HDM2, and HDM4 binding to human S100B. Biochemistry 2012; 51:7189-201. [PMID: 22913742 PMCID: PMC3448795 DOI: 10.1021/bi300865g] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
S100B is a member of the S100 subfamily of EF-hand proteins that has been implicated in malignant melanoma and neurodegenerative conditions such as Alzheimer's disease and Parkinson's disease. Calcium-induced conformational changes expose a hydrophobic binding cleft, facilitating interactions with a wide variety of nuclear, cytoplasmic, and extracellular target proteins. Previously, peptides derived from CapZ, p53, NDR, HDM2, and HDM4 have been shown to interact with S100B in a calcium-dependent manner. However, the thermodynamic and kinetic basis of these interactions remains largely unknown. To gain further insight, we screened these peptides against the S100B protein using isothermal titration calorimetry and nuclear magnetic resonance. All peptides were found to have binding affinities in the low micromolar to nanomolar range. Binding-induced changes in the line shapes of S100B backbone (1)H and (15)N resonances were monitored to obtain the dissociation constants and the kinetic binding parameters. The large microscopic K(on) rate constants observed in this study (≥1 × 10(7) M(-1) s(-1)) suggest that S100B utilizes a "fly casting mechanism" in the recognition of these peptide targets.
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Affiliation(s)
- Lucas N. Wafer
- Center for Biotechnology and Interdisciplinary Studies and Department of Biology, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180, USA
| | | | - Scott A. McCallum
- Center for Biotechnology and Interdisciplinary Studies and Department of Biology, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180, USA
| | - George I. Makhatadze
- Center for Biotechnology and Interdisciplinary Studies and Department of Biology, Rensselaer Polytechnic Institute, 110 8th Street, Troy, New York 12180, USA
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25
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Feldmann EA, Ni S, Sahu ID, Mishler CH, Risser DD, Murakami JL, Tom SK, McCarrick RM, Lorigan GA, Tolbert BS, Callahan SM, Kennedy MA. Evidence for Direct Binding between HetR from Anabaena sp. PCC 7120 and PatS-5. Biochemistry 2011; 50:9212-24. [DOI: 10.1021/bi201226e] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Erik A. Feldmann
- Department of Chemistry and
Biochemistry, Miami University, Oxford,
Ohio 45056, United States
| | - Shuisong Ni
- Department of Chemistry and
Biochemistry, Miami University, Oxford,
Ohio 45056, United States
| | - Indra D. Sahu
- Department of Chemistry and
Biochemistry, Miami University, Oxford,
Ohio 45056, United States
| | - Clay H. Mishler
- Department of Chemistry and
Biochemistry, Miami University, Oxford,
Ohio 45056, United States
| | - Douglas D. Risser
- Department of Microbiology, University of Hawaii, Honolulu, Hawaii 96822, United
States
| | - Jodi L. Murakami
- Department of Microbiology, University of Hawaii, Honolulu, Hawaii 96822, United
States
| | - Sasa K. Tom
- Department of Microbiology, University of Hawaii, Honolulu, Hawaii 96822, United
States
| | - Robert M. McCarrick
- Department of Chemistry and
Biochemistry, Miami University, Oxford,
Ohio 45056, United States
| | - Gary A. Lorigan
- Department of Chemistry and
Biochemistry, Miami University, Oxford,
Ohio 45056, United States
| | - Blanton S. Tolbert
- Department of Chemistry and
Biochemistry, Miami University, Oxford,
Ohio 45056, United States
| | - Sean M. Callahan
- Department of Microbiology, University of Hawaii, Honolulu, Hawaii 96822, United
States
| | - Michael A. Kennedy
- Department of Chemistry and
Biochemistry, Miami University, Oxford,
Ohio 45056, United States
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26
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Cmoch A, Strzelecka-Kiliszek A, Palczewska M, Groves P, Pikula S. Matrix vesicles isolated from mineralization-competent Saos-2 cells are selectively enriched with annexins and S100 proteins. Biochem Biophys Res Commun 2011; 412:683-7. [PMID: 21867690 DOI: 10.1016/j.bbrc.2011.08.025] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2011] [Accepted: 08/07/2011] [Indexed: 02/06/2023]
Abstract
Matrix vesicles (MVs) are cell-derived membranous entities crucial for mineral formation in the extracellular matrix. One of the dominant groups of constitutive proteins present in MVs, recognised as regulators of mineralization in norm and pathology, are annexins. In this report, besides the annexins already described (AnxA2 and AnxA6), we identified AnxA1 and AnxA7, but not AnxA4, to become selectively enriched in MVs of Saos-2 cells upon stimulation for mineralization. Among them, AnxA6 was found to be almost EGTA-non extractable from matrix vesicles. Moreover, our report provides the first evidence of annexin-binding S100 proteins to be present in MVs of mineralizing cells. We observed that S100A10 and S100A6, but not S100A11, were selectively translocated to the MVs of Saos-2 cells upon mineralization. This observation provides the rationale for more detailed studies on the role of annexin-S100 interactions in MV-mediated mineralization.
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Affiliation(s)
- Anna Cmoch
- Department of Biochemistry, Nencki Institute of Experimental Biology, Warsaw, Poland
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27
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Reddy TRK, Li C, Guo X, Myrvang HK, Fischer PM, Dekker LV. Design, synthesis, and structure-activity relationship exploration of 1-substituted 4-aroyl-3-hydroxy-5-phenyl-1H-pyrrol-2(5H)-one analogues as inhibitors of the annexin A2-S100A10 protein interaction. J Med Chem 2011; 54:2080-94. [PMID: 21375334 PMCID: PMC3081224 DOI: 10.1021/jm101212e] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
S100 proteins are small adaptors that regulate the activity of partner proteins by virtue of direct protein interactions. Here, we describe the first small molecule blockers of the interaction between S100A10 and annexin A2. Molecular docking yielded candidate blockers that were screened for competition of the binding of an annexin A2 peptide to S100A10. Several inhibitory clusters were identified with some containing compounds with potency in the lower micromolar range. We chose 3-hydroxy-1-(2-hydroxypropyl)-5-(4-isopropylphenyl)-4-(4-methylbenzoyl)-1H-pyrrol-2(5H)-one (1a) as a starting point for structure-activity studies. These confirmed the hypothetical binding mode from the virtual screen for this series of molecules. Selected compounds disrupted the physiological complex of annexin A2 and S100A10, both in a broken cell preparation and inside MDA-MB-231 breast cancer cells. Thus, this class of compounds has promising properties as inhibitors of the interaction between annexin A2 and S100A10 and may help to elucidate the cellular function of this protein interaction.
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Affiliation(s)
- Tummala R K Reddy
- School of Pharmacy, Centre for Biomolecular Sciences, University of Nottingham, Nottingham NG7 2RD, United Kingdom
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Dorovkov MV, Kostyukova AS, Ryazanov AG. Phosphorylation of annexin A1 by TRPM7 kinase: a switch regulating the induction of an α-helix. Biochemistry 2011; 50:2187-93. [PMID: 21280599 PMCID: PMC3062375 DOI: 10.1021/bi101963h] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
TRPM7 is an unusual bifunctional protein consisting of an α-kinase domain fused to a TRP ion channel. Previously, we have identified annexin A1 as a substrate for TRPM7 kinase and found that TRPM7 phosphorylates annexin A1 at Ser5 within the N-terminal α-helix. Annexin A1 is a Ca(2+)-dependent membrane binding protein, which has been implicated in membrane trafficking and reorganization. The N-terminal tail of annexin A1 can interact with either membranes or S100A11 protein, and it adopts the conformation of an amphipathic α-helix upon these interactions. Moreover, the existing evidence indicates that the formation of an α-helix is essential for these interactions. Here we show that phosphorylation at Ser5 prevents the N-terminal peptide of annexin A1 from adopting an α-helical conformation in the presence of membrane-mimetic micelles as well as phospholipid vesicles. We also show that phosphorylation at Ser5 dramatically weakens the binding of the peptide to S100A11. Our data suggest that phosphorylation at Ser5 regulates the interaction of annexin A1 with membranes as well as S100A11 protein.
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Affiliation(s)
- Maxim V Dorovkov
- Department of Pharmacology, University of Medicine and Dentistry of New Jersey-Robert Wood Johnson Medical School, 675 Hoes Lane, Piscataway, New Jersey 08854, United States.
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Streicher WW, Lopez MM, Makhatadze GI. Modulation of quaternary structure of S100 proteins by calcium ions. Biophys Chem 2010; 151:181-6. [PMID: 20621410 DOI: 10.1016/j.bpc.2010.06.003] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2010] [Revised: 06/16/2010] [Accepted: 06/17/2010] [Indexed: 11/15/2022]
Abstract
It is well established that calcium binding leads to conformational changes in S100 proteins. These conformational changes are thought to activate the protein and render a protein conformation that is capable of binding other proteins. The basic quaternary structural motif of S100 proteins is a homodimer, however there is little information if higher order non-covalent oligomers are also formed and whether these oligomers are of functional relevance. To this end we performed equilibrium analytical ultracentrifugation experiments for 16 S100 proteins (S100A1, S100A2, S100A3, S100A4, S100A5, S100A6, S100A7, S100A8, S100A9, S100A10, S100A11, S100A12, S100A13, S100B, S100P, and S100Z) under reducing conditions in the absence and presence of calcium ions. We show that the addition of calcium promotes the formation of tetrameric structures which could be further enhanced under in vivo conditions where there is an additional effect of molecular crowding.
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Affiliation(s)
- Werner W Streicher
- Center for Biotechnology and Interdisciplinary Studies and Department of Biology, Rensselaer Polytechnic Institute, Troy, NY 12065, USA
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Li C, Reddy TRK, Fischer PM, Dekker LV. A Cy5-labeled S100A10 tracer used to identify inhibitors of the protein interaction with annexin A2. Assay Drug Dev Technol 2010; 8:85-95. [PMID: 20085458 DOI: 10.1089/adt.2009.0218] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Protein-protein interactions are increasingly of interest as targets in small-molecule drug discovery. The interaction between the Ca2+- and phospholipid-binding protein Annexin A2 and its binding partner S100A10 has been implicated in angiogenesis and cancer metastasis. Here, we present a methodology to screen for inhibitors of this protein interaction. We developed a Cy5-labeled S100A10 tracer and showed by circular dichroism spectroscopy that the secondary structure is indistinguishable from that of non-labeled S100A10. This tracer was used to develop a binding assay based upon fluorescence resonance energy transfer to a Cy3-labeled Annexin A2 peptide ligand. The binding parameters matched those for unlabeled components as observed by equilibrium dialysis, which we determined separately, as well as those determined by isothermal titration calorimetry. Binding of labeled and unlabeled peptide was specific and mutually competitive. We used this assay for screening a small compound library derived by computational interrogation of the S100A10-binding pocket. Hits were obtained with IC(50) values in range of the IC(50) of the cognate Annexin A2 peptide ligand. Hits were subjected to an exact parallel assay measuring an unrelated protein-protein interaction (antigen-antibody). In this way, we identified genuine hits that inhibited the interaction between S100A10 and Annexin A2 but do not affect the fluorescence readout. These compounds are potentially of interest as candidates for further analysis and medical chemistry exploration. The simple assay format described here can be employed in early-stage exploration of other protein-protein interaction targets.
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Affiliation(s)
- Chan Li
- School of Pharmacy, Centre for Biomolecular Sciences, University of Nottingham, United Kingdom
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Talbot NC, Powell AM, Caperna TJ, Garrett WM. Proteomic analysis of the major cellular proteins of bovine trophectoderm cell lines derived from IVP, parthenogenetic and nuclear transfer embryos: Reduced expression of annexins I and II in nuclear transfer-derived cell lines. Anim Reprod Sci 2010; 120:187-202. [PMID: 20400246 DOI: 10.1016/j.anireprosci.2010.03.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2009] [Revised: 03/11/2010] [Accepted: 03/23/2010] [Indexed: 10/19/2022]
Abstract
Trophectoderm cell lines were established from 8-day in vitro-cultured embryos of cattle derived from fertilization (IVF), somatic cell nuclear transfer (NT), or parthenogenetic activation (P) of in vitro-matured oocytes and from five 8-day-old in vivo (V) embryos. The most abundant cellular proteins of 5 V-, 16 NT-, 12 P-, and 16 IVF-derived cell lines were compared by 2D-gel electrophoresis and mass spectrometry; that is, the unaltered thiourea/urea extract of each cell culture was analyzed. Common protein spots (n=118) were examined, and 95% were identified with significant scores from protein and gene database searches. Of the proteins detected and identified, actin and cytokeratin-8 were found to be the most abundant. Other prominent cellular proteins were metabolic enzymes such as aldose reductase, phosphoglycerate mutase, enolase, triosephosphate isomerase, cytoskeletal interacting proteins transgelin and stratifin, anti-oxidant proteins peroxiredoxin 1 and anti-oxidant protein 2, and the calcium-dependent lipid-binding proteins annexins I and II. In comparative analysis of the 2D-gels, the NT-derived trophectoderm had less annexins I and II in comparison to the IVF- and P-derived trophectoderm. Because annexins I and II are abundant in the placenta and have functions important to the maintenance of placentation, the down-regulation of the annexin genes in the cultured NT trophectoderm may be related to the frequent failures of NT pregnancies.
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Affiliation(s)
- Neil C Talbot
- U.S. Department of Agriculture, Agricultural Research Service USDA, ARS, Animal and Natural Resources Institute, Animal Biosciences and Biotechnology Laboratory, Beltsville Agricultural Research Center, Beltsville, MD 20705-2350, United States.
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Rezvanpour A, Phillips JM, Shaw GS. Design of high-affinity S100-target hybrid proteins. Protein Sci 2010; 18:2528-36. [PMID: 19827097 DOI: 10.1002/pro.267] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
S100B and S100A10 are dimeric, EF-hand proteins. S100B undergoes a calcium-dependent conformational change allowing it to interact with a short contiguous sequence from the actin-capping protein CapZ (TRTK12). S100A10 does not bind calcium but is able to recruit the N-terminus of annexin A2 important for membrane fusion events, and to form larger multiprotein complexes such as that with the cation channel proteins TRPV5/6. In this work, we have designed, expressed, purified, and characterized two S100-target peptide hybrid proteins comprised of S100A10 and S100B linked in tandem to annexin A2 (residues 1-15) and CapZ (TRTK12), respectively. Different protease cleavage sites (tobacco etch virus, PreScission) were incorporated into the linkers of the hybrid proteins. In situ proteolytic cleavage monitored by (1)H-(15)N HSQC spectra showed the linker did not perturb the structures of the S100A10-annexin A2 or S100B-TRTK12 complexes. Furthermore, the analysis of the chemical shift assignments ((1)H, (15)N, and (13)C) showed that residues T102-S108 of annexin A2 formed a well-defined alpha-helix in the S100A10 hybrid while the TRTK12 region was unstructured at the N-terminus with a single turn of alpha-helix from D108-K111 in the S100B hybrid protein. The two S100 hybrid proteins provide a simple yet extremely efficient method for obtaining high yields of intact S100 target peptides. Since cleavage of the S100 hybrid protein is not necessary for structural characterization, this approach may be useful as a scaffold for larger S100 complexes.
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Affiliation(s)
- Atoosa Rezvanpour
- Department of Biochemistry, University of Western Ontario, London, Ontario, Canada
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Nikoulina SE, Andon NL, McCowen KM, Hendricks MD, Lowe C, Taylor SW. A primary colonic crypt model enriched in enteroendocrine cells facilitates a peptidomic survey of regulated hormone secretion. Mol Cell Proteomics 2010; 9:728-41. [PMID: 20081152 DOI: 10.1074/mcp.m900529-mcp200] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
To enable the first physiologically relevant peptidomic survey of gastrointestinal tissue, we have developed a primary mouse colonic crypt model enriched for enteroendocrine L-cells. The cells in this model were phenotypically profiled using PCR-based techniques and showed peptide hormone and secretory and processing marker expression at mRNA levels that were increased relative to the parent tissue. Co-localization of glucagon-like peptide-1 and peptide YY, a characteristic feature of L-cells, was demonstrated by double label immunocytochemistry. The L-cells displayed regulated hormone secretion in response to physiological and pharmacological stimuli as measured by immunoassay. Using a high resolution mass spectrometry-based platform, more than 50 endogenous peptides (<16 kDa), including all known major hormones, were identified a priori. The influence of culture conditions on peptide relative abundance and post-translational modification was characterized. The relative abundance of secreted peptides in the presence/absence of the stimulant forskolin was measured by label-free quantification. All peptides exhibiting a statistically significant increase in relative concentration in the culture media were derived from prohormones, consistent with a cAMP-coupled response. The only peptides that exhibited a statistically significant decrease in secretion on forskolin stimulation were derived from annexin A1 and calcyclin. Biophysical interactions between annexin A1 and calcyclin have been reported very recently and may have functional consequences. This work represents the first step in characterizing physiologically relevant peptidomic secretion of gastrointestinally derived primary cells and will aid in elucidating new endocrine function.
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