1
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Wei CC, Razzak AA, Ghasemi H, Khedri R, Fraase A. Ca 2+ binding shifts dimeric dual oxidase's truncated EF-hand domain to monomer. Biophys Chem 2024; 312:107271. [PMID: 38852484 DOI: 10.1016/j.bpc.2024.107271] [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: 12/15/2023] [Revised: 04/17/2024] [Accepted: 05/22/2024] [Indexed: 06/11/2024]
Abstract
Hydrogen peroxide, produced by Dual Oxidase (Duox), is essential for thyroid hormone synthesis. Duox activation involves Ca2+ binding to its EF-hand Domain (EFD), which contains two EF-hands (EFs). In this study, we characterized a truncated EFD using spectrometry, calorimetry, electrophoretic mobility, and gel filtration to obtain its Ca2+ binding thermodynamic and kinetics, as well as to assess the associated conformational changes. Our results revealed that its 2nd EF-hand (EF2) exhibits a strong exothermic Ca2+ binding (Ka = 107 M-1) while EF1 shows a weaker binding (Ka = 105 M-1), resulting in the burial of its negatively charged residues. The Ca2+ binding to EFD results in a stable structure with a melting temperature shifting from 67 to 99 °C and induces a structural transition from a dimeric to monomeric form. EF2 appears to play a role in dimer formation in its apo form, while the hydrophobic exposure of Ca2+-bound-EF1 is crucial for dimer formation in its holo form. The result is consistent with structures obtained from Cryo-EM, indicating that a stable structure of EFD with hydrophobic patches upon Ca2+ binding is vital for its Duox's domain-domain interaction for electron transfer.
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Affiliation(s)
- Chin-Chuan Wei
- Department of Chemistry, College of Arts and Sciences, Southern Illinois University Edwardsville, Edwardsville, IL 62026, USA; Department of Pharmaceutical Sciences, College of Pharmacy, Southern Illinois University Edwardsville, Edwardsville, IL 62026, USA.
| | - Amena Abdul Razzak
- Department of Chemistry, College of Arts and Sciences, Southern Illinois University Edwardsville, Edwardsville, IL 62026, USA
| | - Hadis Ghasemi
- Department of Chemistry, College of Arts and Sciences, Southern Illinois University Edwardsville, Edwardsville, IL 62026, USA
| | - Rahil Khedri
- Department of Chemistry, College of Arts and Sciences, Southern Illinois University Edwardsville, Edwardsville, IL 62026, USA
| | - Alexandria Fraase
- Department of Chemistry, College of Arts and Sciences, Southern Illinois University Edwardsville, Edwardsville, IL 62026, USA
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2
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Danowska M, Strączkowski M. The Ca2+/Calmodulin-dependent Calcineurin/NFAT Signaling Pathway in the Pathogenesis of Insulin Resistance in Skeletal Muscle. Exp Clin Endocrinol Diabetes 2023; 131:589-594. [PMID: 37875146 DOI: 10.1055/a-2174-7958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2023]
Abstract
Skeletal muscle is the tissue directly involved in insulin-stimulated glucose uptake. Glucose is the primary energy substrate for contracting muscles, and proper metabolism of glucose is essential for health. Contractile activity and the associated Ca2+signaling regulate functional capacity and muscle mass. A high concentration of Ca2+and the presence of calmodulin (CaM) leads to the activation of calcineurin (CaN), a protein with serine-threonine phosphatase activity. The signaling pathway linked with CaN and transcription factors like the nuclear factor of activated T cells (NFAT) is essential for skeletal muscle development and reprogramming of fast-twitch to slow-twitch fibers. CaN activation may promote metabolic adaptations in muscle cells, resulting in better insulin-stimulated glucose transport. The molecular mechanisms underlying the altered insulin response remain unclear. The role of the CaN/NFAT pathway in regulating skeletal muscle hypertrophy is better described than its involvement in the pathogenesis of insulin resistance. Thus, there are opportunities for future research in that field. This review presents the role of CaN/NFAT signaling and suggests the relationship with insulin-resistant muscles.
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Affiliation(s)
- Magdalena Danowska
- Department of Prophylaxis of Metabolic Diseases, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, Olsztyn, Poland
| | - Marek Strączkowski
- Department of Prophylaxis of Metabolic Diseases, Institute of Animal Reproduction and Food Research, Polish Academy of Sciences, Olsztyn, Poland
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3
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Thiel G, Rössler OG. Calmodulin Regulates Transient Receptor Potential TRPM3 and TRPM8-Induced Gene Transcription. Int J Mol Sci 2023; 24:ijms24097902. [PMID: 37175607 PMCID: PMC10178570 DOI: 10.3390/ijms24097902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2023] [Revised: 04/23/2023] [Accepted: 04/24/2023] [Indexed: 05/15/2023] Open
Abstract
Calmodulin is a small protein that binds Ca2+ ions via four EF-hand motifs. The Ca2+/calmodulin complex as well as Ca2+-free calmodulin regulate the activities of numerous enzymes and ion channels. Here, we used genetic and pharmacological tools to study the functional role of calmodulin in regulating signal transduction of TRPM3 and TRPM8 channels. Both TRPM3 and TRPM8 are important regulators of thermosensation. Gene transcription triggered by stimulation of TRPM3 or TRPM8 channels was significantly impaired in cells expressing a calmodulin mutant with mutations in all four EF-hand Ca2+ binding motifs. Similarly, incubation of cells with the calmodulin inhibitor ophiobolin A reduced TRPM3 and TRPM8-induced signaling. The Ca2+/calmodulin-dependent protein phosphatase calcineurin was shown to negatively regulate TRPM3-induced gene transcription. Here, we show that TRPM8-induced transcription is also regulated by calcineurin. We propose that calmodulin plays a dual role in regulating TRPM3 and TRPM8 functions. Calmodulin is required for the activation of TRPM3 and TRPM8-induced intracellular signaling, most likely through a direct interaction with the channels. Ca2+ influx through TRPM3 and TRPM8 feeds back to TRPM3 and TRPM8-induced signaling by activation of the calmodulin-regulated enzyme calcineurin, which acts as a negative feedback loop for both TRPM3 and TRPM8 channel signaling.
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Affiliation(s)
- Gerald Thiel
- Department of Medical Biochemistry and Molecular Biology, Saarland University, Building 44, 66421 Homburg, Germany
| | - Oliver G Rössler
- Department of Medical Biochemistry and Molecular Biology, Saarland University, Building 44, 66421 Homburg, Germany
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4
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Wang H, Liu Y, Sun Y, Dong J, Xu X, Wang H, Zhao X, Zhang J, Yao B, Zhao L, Liu S, Peng R. Changes in cognitive function, synaptic structure and protein expression after long-term exposure to 2.856 and 9.375 GHz microwaves. Cell Commun Signal 2023; 21:34. [PMID: 36782203 PMCID: PMC9926547 DOI: 10.1186/s12964-022-01011-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 12/04/2022] [Indexed: 02/15/2023] Open
Abstract
Health hazards from long-term exposure to microwaves, especially the potential for changes in cognitive function, are attracting increasing attention. The purpose of this study was to explore changes in spatial learning and memory and synaptic structure and to identify differentially expressed proteins in hippocampal and serum exosomes after long-term exposure to 2.856 and 9.375 GHz microwaves. The spatial reference learning and memory abilities and the structure of the DG area were impaired after long-term exposure to 2.856 and 9.375 GHz microwaves. We also found a decrease in SNARE-associated protein Snapin and an increase in charged multivesicular body protein 3 in the hippocampus, indicating that synaptic vesicle recycling was inhibited and consistent with the large increase in presynaptic vesicles. Moreover, we investigated changes in serum exosomes after 2.856 and 9.375 GHz microwave exposure. The results showed that long-term 2.856 GHz microwave exposure could induce a decrease in calcineurin subunit B type 1 and cytochrome b-245 heavy chain in serum exosomes. While the 9.375 GHz long-term microwave exposure induced a decrease in proteins (synaptophysin-like 1, ankyrin repeat and rabankyrin-5, protein phosphatase 3 catalytic subunit alpha and sodium-dependent phosphate transporter 1) in serum exosomes. In summary, long-term microwave exposure could lead to different degrees of spatial learning and memory impairment, EEG disturbance, structural damage to the hippocampus, and differential expression of hippocampal tissue and serum exosomes.
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Affiliation(s)
- Hui Wang
- grid.506261.60000 0001 0706 7839Beijing Institute of Radiation Medicine, Beijing, 100850 China
| | - Yu Liu
- grid.506261.60000 0001 0706 7839Beijing Institute of Radiation Medicine, Beijing, 100850 China
| | - Yunbo Sun
- grid.506261.60000 0001 0706 7839Beijing Institute of Radiation Medicine, Beijing, 100850 China
| | - Ji Dong
- grid.506261.60000 0001 0706 7839Beijing Institute of Radiation Medicine, Beijing, 100850 China
| | - Xinping Xu
- grid.506261.60000 0001 0706 7839Beijing Institute of Radiation Medicine, Beijing, 100850 China
| | - Haoyu Wang
- grid.506261.60000 0001 0706 7839Beijing Institute of Radiation Medicine, Beijing, 100850 China
| | - Xuelong Zhao
- grid.506261.60000 0001 0706 7839Beijing Institute of Radiation Medicine, Beijing, 100850 China
| | - Jing Zhang
- grid.506261.60000 0001 0706 7839Beijing Institute of Radiation Medicine, Beijing, 100850 China
| | - Binwei Yao
- grid.506261.60000 0001 0706 7839Beijing Institute of Radiation Medicine, Beijing, 100850 China
| | - Li Zhao
- Beijing Institute of Radiation Medicine, Beijing, 100850, China.
| | - Shuchen Liu
- Beijing Institute of Radiation Medicine, Beijing, 100850, China.
| | - Ruiyun Peng
- Beijing Institute of Radiation Medicine, Beijing, 100850, China.
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5
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Leong E, Pang Z, Stadnyk AW, Lin TJ. Calcineurin Aα Contributes to IgE-Dependent Mast-Cell Mediator Secretion in Allergic Inflammation. J Innate Immun 2021; 14:320-334. [PMID: 34839285 PMCID: PMC9274814 DOI: 10.1159/000520040] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 09/26/2021] [Indexed: 11/19/2022] Open
Abstract
Mast cells (MCs) are key mediators of allergic inflammation through the activation of cross-linked immunoglobulin E (IgE) bound to the high-affinity IgE receptor (FcϵRI) on the cell surface, leading to the release of biologically potent mediators, either from preformed granules or newly synthesized. Pharmacological inhibitors have been developed to target a key signaling protein phosphatase in this pathway, calcineurin, yet there is a lack of genetic and definitive evidence for the various isoforms of calcineurin subunits in FcϵRI-mediated responses. In this study, we hypothesized that deficiency in the calcineurin Aα isoform will result in a decreased allergic immune response by the MCs. In a model of passive cutaneous anaphylaxis, there was a reduction in vascular permeability in MC-deficient mouse tissues reconstituted with calcineurin subunit A (CnAα) gene-knockout (CnAα<sup>−/−</sup>) MCs, and in vitro experiments identified a significant reduction in release of preformed mediators from granules. Furthermore, released levels of de novo synthesized cytokines were reduced upon FcϵRI activation of CnAα<sup>−/−</sup> MCs in vitro. Characterizing the mechanisms associated with this deficit response, we found a significant impairment of nuclear factor of kappa light polypeptide gene enhancer in B cell phosphorylation and impaired nuclear factor kappa-light-chain-enhancer of activated B-cell inhibitor alpha (NF-κB) activation. Thus, we concluded that CnAα contributes to the release of preformed mediators and newly synthesized mediators from FcϵRI-mediated activation of MCs, and this regulation includes NF-κB signaling.
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Affiliation(s)
- Edwin Leong
- Department of Pathology, Dalhousie University, Halifax, Nova Scotia, Canada,
| | - Zheng Pang
- Department of Pathology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Andrew W Stadnyk
- Department of Pathology, Dalhousie University, Halifax, Nova Scotia, Canada.,Department of Pediatrics, Isaac Walton Killam Health Centre, Halifax, Nova Scotia, Canada.,Department of Microbiology & Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Tong-Jun Lin
- Department of Pathology, Dalhousie University, Halifax, Nova Scotia, Canada.,Department of Pediatrics, Isaac Walton Killam Health Centre, Halifax, Nova Scotia, Canada.,Department of Microbiology & Immunology, Dalhousie University, Halifax, Nova Scotia, Canada
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6
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Structural Insights into Protein Regulation by Phosphorylation and Substrate Recognition of Protein Kinases/Phosphatases. Life (Basel) 2021; 11:life11090957. [PMID: 34575106 PMCID: PMC8467178 DOI: 10.3390/life11090957] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2021] [Revised: 09/05/2021] [Accepted: 09/10/2021] [Indexed: 12/30/2022] Open
Abstract
Protein phosphorylation is one of the most widely observed and important post-translational modification (PTM) processes. Protein phosphorylation is regulated by protein kinases, each of which covalently attaches a phosphate group to an amino acid side chain on a serine (Ser), threonine (Thr), or tyrosine (Tyr) residue of a protein, and by protein phosphatases, each of which, conversely, removes a phosphate group from a phosphoprotein. These reversible enzyme activities provide a regulatory mechanism by activating or deactivating many diverse functions of proteins in various cellular processes. In this review, their structures and substrate recognition are described and summarized, focusing on Ser/Thr protein kinases and protein Ser/Thr phosphatases, and the regulation of protein structures by phosphorylation. The studies reviewed here and the resulting information could contribute to further structural, biochemical, and combined studies on the mechanisms of protein phosphorylation and to drug discovery approaches targeting protein kinases or protein phosphatases.
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7
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Structures of human dual oxidase 1 complex in low-calcium and high-calcium states. Nat Commun 2021; 12:155. [PMID: 33420071 PMCID: PMC7794343 DOI: 10.1038/s41467-020-20466-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 12/02/2020] [Indexed: 01/29/2023] Open
Abstract
Dual oxidases (DUOXs) produce hydrogen peroxide by transferring electrons from intracellular NADPH to extracellular oxygen. They are involved in many crucial biological processes and human diseases, especially in thyroid diseases. DUOXs are protein complexes co-assembled from the catalytic DUOX subunits and the auxiliary DUOXA subunits and their activities are regulated by intracellular calcium concentrations. Here, we report the cryo-EM structures of human DUOX1-DUOXA1 complex in both high-calcium and low-calcium states. These structures reveal the DUOX1 complex is a symmetric 2:2 hetero-tetramer stabilized by extensive inter-subunit interactions. Substrate NADPH and cofactor FAD are sandwiched between transmembrane domain and the cytosolic dehydrogenase domain of DUOX. In the presence of calcium ions, intracellular EF-hand modules might enhance the catalytic activity of DUOX by stabilizing the dehydrogenase domain in a conformation that allows electron transfer.
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8
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Abstract
The serine/threonine phosphatase calcineurin acts as a crucial connection between calcium signaling the phosphorylation states of numerous important substrates. These substrates include, but are not limited to, transcription factors, receptors and channels, proteins associated with mitochondria, and proteins associated with microtubules. Calcineurin is activated by increases in intracellular calcium concentrations, a process that requires the calcium sensing protein calmodulin binding to an intrinsically disordered regulatory domain in the phosphatase. Despite having been studied for around four decades, the activation of calcineurin is not fully understood. This review largely focuses on what is known about the activation process and highlights aspects that are currently not understood. Video abstract.
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Affiliation(s)
- Trevor P Creamer
- Center for Structural Biology, Department of Molecular & Cellular Biochemistry, 741 S. Limestone Street, Lexington, KY, 40536-0509, USA.
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9
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Regulation of cell adhesion: a collaborative effort of integrins, their ligands, cytoplasmic actors, and phosphorylation. Q Rev Biophys 2019; 52:e10. [PMID: 31709962 DOI: 10.1017/s0033583519000088] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Integrins are large heterodimeric type 1 membrane proteins expressed in all nucleated mammalian cells. Eighteen α-chains and eight β-chains can combine to form 24 different integrins. They are cell adhesion proteins, which bind to a large variety of cellular and extracellular ligands. Integrins are required for cell migration, hemostasis, translocation of cells out from the blood stream and further movement into tissues, but also for the immune response and tissue morphogenesis. Importantly, integrins are not usually active as such, but need activation to become adhesive. Integrins are activated by outside-in activation through integrin ligand binding, or by inside-out activation through intracellular signaling. An important question is how integrin activity is regulated, and this topic has recently drawn much attention. Changes in integrin affinity for ligand binding are due to allosteric structural alterations, but equally important are avidity changes due to integrin clustering in the plane of the plasma membrane. Recent studies have partially solved how integrin cell surface structures change during activation. The integrin cytoplasmic domains are relatively short, but by interacting with a variety of cytoplasmic proteins in a regulated manner, the integrins acquire a number of properties important not only for cell adhesion and movement, but also for cellular signaling. Recent work has shown that specific integrin phosphorylations play pivotal roles in the regulation of integrin activity. Our purpose in this review is to integrate the present knowledge to enable an understanding of how cell adhesion is dynamically regulated.
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10
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Villalobo A, González-Muñoz M, Berchtold MW. Proteins with calmodulin-like domains: structures and functional roles. Cell Mol Life Sci 2019; 76:2299-2328. [PMID: 30877334 PMCID: PMC11105222 DOI: 10.1007/s00018-019-03062-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 02/26/2019] [Accepted: 03/07/2019] [Indexed: 12/21/2022]
Abstract
The appearance of modular proteins is a widespread phenomenon during the evolution of proteins. The combinatorial arrangement of different functional and/or structural domains within a single polypeptide chain yields a wide variety of activities and regulatory properties to the modular proteins. In this review, we will discuss proteins, that in addition to their catalytic, transport, structure, localization or adaptor functions, also have segments resembling the helix-loop-helix EF-hand motifs found in Ca2+-binding proteins, such as calmodulin (CaM). These segments are denoted CaM-like domains (CaM-LDs) and play a regulatory role, making these CaM-like proteins sensitive to Ca2+ transients within the cell, and hence are able to transduce the Ca2+ signal leading to specific cellular responses. Importantly, this arrangement allows to this group of proteins direct regulation independent of other Ca2+-sensitive sensor/transducer proteins, such as CaM. In addition, this review also covers CaM-binding proteins, in which their CaM-binding site (CBS), in the absence of CaM, is proposed to interact with other segments of the same protein denoted CaM-like binding site (CLBS). CLBS are important regulatory motifs, acting either by keeping these CaM-binding proteins inactive in the absence of CaM, enhancing the stability of protein complexes and/or facilitating their dimerization via CBS/CLBS interaction. The existence of proteins containing CaM-LDs or CLBSs substantially adds to the enormous versatility and complexity of Ca2+/CaM signaling.
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Affiliation(s)
- Antonio Villalobo
- Department of Cancer Biology, Instituto de Investigaciones Biomédicas, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Arturo Duperier 4, 28029, Madrid, Spain.
- Instituto de Investigaciones Sanitarias, Hospital Universitario La Paz, Edificio IdiPAZ, Paseo de la Castellana 261, 28046, Madrid, Spain.
| | - María González-Muñoz
- Department of Cancer Biology, Instituto de Investigaciones Biomédicas, Consejo Superior de Investigaciones Científicas and Universidad Autónoma de Madrid, Arturo Duperier 4, 28029, Madrid, Spain
| | - Martin W Berchtold
- Department of Biology, University of Copenhagen, 13 Universitetsparken, 2100, Copenhagen, Denmark.
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11
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Meng F, Kurgan L. High‐throughput prediction of disordered moonlighting regions in protein sequences. Proteins 2018; 86:1097-1110. [DOI: 10.1002/prot.25590] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Revised: 07/25/2018] [Accepted: 08/05/2018] [Indexed: 01/20/2023]
Affiliation(s)
- Fanchi Meng
- Department of Electrical and Computer Engineering University of Alberta Edmonton Canada
| | - Lukasz Kurgan
- Department of Electrical and Computer Engineering University of Alberta Edmonton Canada
- Department of Computer Science Virginia Commonwealth University Richmond VA
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12
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Offley SR, Schmidt MC. Protein phosphatases of Saccharomyces cerevisiae. Curr Genet 2018; 65:41-55. [PMID: 30225534 DOI: 10.1007/s00294-018-0884-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 08/27/2018] [Accepted: 09/08/2018] [Indexed: 10/28/2022]
Abstract
The phosphorylation status of a protein is highly regulated and is determined by the opposing activities of protein kinases and protein phosphatases within the cell. While much is known about the protein kinases found in Saccharomyces cerevisiae, the protein phosphatases are much less characterized. Of the 127 protein kinases in yeast, over 90% are in the same evolutionary lineage. In contrast, protein phosphatases are fewer in number (only 43 have been identified in yeast) and comprise multiple, distinct evolutionary lineages. Here we review the protein phosphatase families of yeast with regard to structure, catalytic mechanism, regulation, and signal transduction participation.
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Affiliation(s)
- Sarah R Offley
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, 450 Technology Drive, Pittsburgh, PA, 15219, USA
| | - Martin C Schmidt
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, 450 Technology Drive, Pittsburgh, PA, 15219, USA.
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13
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O’Brien DP, Durand D, Voegele A, Hourdel V, Davi M, Chamot-Rooke J, Vachette P, Brier S, Ladant D, Chenal A. Calmodulin fishing with a structurally disordered bait triggers CyaA catalysis. PLoS Biol 2017; 15:e2004486. [PMID: 29287065 PMCID: PMC5764468 DOI: 10.1371/journal.pbio.2004486] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 01/11/2018] [Accepted: 12/07/2017] [Indexed: 11/18/2022] Open
Abstract
Once translocated into the cytosol of target cells, the catalytic domain (AC) of the adenylate cyclase toxin (CyaA), a major virulence factor of Bordetella pertussis, is potently activated by binding calmodulin (CaM) to produce supraphysiological levels of cAMP, inducing cell death. Using a combination of small-angle X-ray scattering (SAXS), hydrogen/deuterium exchange mass spectrometry (HDX-MS), and synchrotron radiation circular dichroism (SR-CD), we show that, in the absence of CaM, AC exhibits significant structural disorder, and a 75-residue-long stretch within AC undergoes a disorder-to-order transition upon CaM binding. Beyond this local folding, CaM binding induces long-range allosteric effects that stabilize the distant catalytic site, whilst preserving catalytic loop flexibility. We propose that the high enzymatic activity of AC is due to a tight balance between the CaM-induced decrease of structural flexibility around the catalytic site and the preservation of catalytic loop flexibility, allowing for fast substrate binding and product release. The CaM-induced dampening of AC conformational disorder is likely relevant to other CaM-activated enzymes. Calmodulin is a widespread and highly conserved protein that interacts with a wide variety of eukaryotic proteins and enzymes, controlling their activities in response to calcium. The adenylate cyclase toxin (CyaA) of Bordetella pertussis, the causative agent of whooping cough, is one such calmodulin target. Once transported across the plasma membrane of eukaryotic cells, the catalytic domain (AC) of CyaA is activated by calmodulin, producing high levels of cAMP, which can induce cell death. We use an integrative structural biology approach combining several biophysical techniques to characterize the structural rearrangements in AC upon calmodulin binding and to elucidate their relationship to CyaA activation. We show that a disordered stretch of 75 amino acid residues in AC serves as a bait for calmodulin capture. Binding induces significant folding within this region, a prerequisite for CyaA activation. Calmodulin binding promotes the stabilization of the distant catalytic site, whilst maintaining its catalytic loop in a flexible and exposed state. Both phenomena contribute to the high enzymatic activity of AC, allowing for fast substrate binding and cAMP release. The calmodulin-induced reduction of AC conformational disorder is likely relevant to other calmodulin-activated enzymes.
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Affiliation(s)
- Darragh P. O’Brien
- Institut Pasteur, UMR CNRS 3528, Chemistry and Structural Biology Department, Paris, France
| | - Dominique Durand
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette cedex, France
- * E-mail: (A.C.); (D.L.); (D.D.); (S.B.)
| | - Alexis Voegele
- Institut Pasteur, UMR CNRS 3528, Chemistry and Structural Biology Department, Paris, France
| | - Véronique Hourdel
- Institut Pasteur, USR CNRS 2000, Chemistry and Structural Biology Department, CITECH, Paris, France
| | - Marilyne Davi
- Institut Pasteur, UMR CNRS 3528, Chemistry and Structural Biology Department, Paris, France
| | - Julia Chamot-Rooke
- Institut Pasteur, USR CNRS 2000, Chemistry and Structural Biology Department, CITECH, Paris, France
| | - Patrice Vachette
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette cedex, France
| | - Sébastien Brier
- Institut Pasteur, USR CNRS 2000, Chemistry and Structural Biology Department, CITECH, Paris, France
- * E-mail: (A.C.); (D.L.); (D.D.); (S.B.)
| | - Daniel Ladant
- Institut Pasteur, UMR CNRS 3528, Chemistry and Structural Biology Department, Paris, France
- * E-mail: (A.C.); (D.L.); (D.D.); (S.B.)
| | - Alexandre Chenal
- Institut Pasteur, UMR CNRS 3528, Chemistry and Structural Biology Department, Paris, France
- * E-mail: (A.C.); (D.L.); (D.D.); (S.B.)
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14
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Yadav DK, Tata SR, Hunt J, Cook EC, Creamer TP, Fitzkee NC. 1H, 15N, and 13C chemical shift assignments of the regulatory domain of human calcineurin. BIOMOLECULAR NMR ASSIGNMENTS 2017; 11:215-219. [PMID: 28803387 PMCID: PMC5693698 DOI: 10.1007/s12104-017-9751-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Accepted: 08/05/2017] [Indexed: 06/01/2023]
Abstract
Calcineurin (CaN) plays an important role in T-cell activation, cardiac system development and nervous system function. Previous studies have demonstrated that the regulatory domain (RD) of CaN binds calmodulin (CaM) towards the N-terminal end. Calcium-loaded CaM activates the serine/threonine phosphatase activity of CaN by binding to the RD, although the mechanistic details of this interaction remain unclear. It is thought that CaM binding at the RD displaces the auto-inhibitory domain (AID) from the active site of CaN, activating phosphatase activity. In the absence of calcium-loaded CaM, the RD is disordered, and binding of CaM induces folding in the RD. In order to provide mechanistic detail about the CaM-CaN interaction, we have undertaken an NMR study of the RD of CaN. Complete 13C, 15N and 1H assignments of the RD of CaN were obtained using solution NMR spectroscopy. The backbone of RD has been assigned using a combination of 13C-detected CON-IPAP experiments as well as traditional HNCO, HNCA, HNCOCA and HNCACB-based 3D NMR spectroscopy. A 15N-resolved TOCSY experiment has been used to assign Hα and Hβ chemical shifts.
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Affiliation(s)
- Dinesh K Yadav
- Department of Chemistry, Mississippi State University, Hand Lab 1115, 310 Presidents Circle, Mississippi State, MS, 39762, USA
| | - Sri Ramya Tata
- Department of Chemistry, Mississippi State University, Hand Lab 1115, 310 Presidents Circle, Mississippi State, MS, 39762, USA
| | - John Hunt
- Department of Chemistry, Mississippi State University, Hand Lab 1115, 310 Presidents Circle, Mississippi State, MS, 39762, USA
| | - Erik C Cook
- Department of Molecular and Cellular Biochemistry, Center for Structural Biology, University of Kentucky, Lexington, USA
| | - Trevor P Creamer
- Department of Molecular and Cellular Biochemistry, Center for Structural Biology, University of Kentucky, Lexington, USA
| | - Nicholas C Fitzkee
- Department of Chemistry, Mississippi State University, Hand Lab 1115, 310 Presidents Circle, Mississippi State, MS, 39762, USA.
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Chyan CL, Irene D, Lin SM. The Recognition of Calmodulin to the Target Sequence of Calcineurin-A Novel Binding Mode. Molecules 2017; 22:E1584. [PMID: 28934144 PMCID: PMC6151454 DOI: 10.3390/molecules22101584] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2017] [Revised: 09/18/2017] [Accepted: 09/18/2017] [Indexed: 11/22/2022] Open
Abstract
Calcineurin (CaN) is a Ca2+/calmodulin-dependent Ser/Thr protein phosphatase, which plays essential roles in many cellular and developmental processes. CaN comprises two subunits, a catalytic subunit (CaN-A, 60 kDa) and a regulatory subunit (CaN-B, 19 kDa). CaN-A tightly binds to CaN-B in the presence of minimal levels of Ca2+, but the enzyme is inactive until activated by CaM. Upon binding to CaM, CaN then undergoes a conformational rearrangement, the auto inhibitory domain is displaced and thus allows for full activity. In order to elucidate the regulatory role of CaM in the activation processes of CaN, we used NMR spectroscopy to determine the structure of the complex of CaM and the target peptide of CaN (CaNp). The CaM/CaNp complex shows a compact ellipsoidal shape with 8 α-helices of CaM wrapping around the CaNp helix. The RMSD of backbone and heavy atoms of twenty lowest energy structures of CaM/CaNp complex are 0.66 and 1.14 Å, respectively. The structure of CaM/CaNp complex can be classified as a novel binding mode family 1-18 with major anchor residues Ile396 and Leu413 to allocate the largest space between two domains of CaM. The relative orientation of CaNp to CaM is similar to the CaMKK peptide in the 1-16 binding mode with N- and C-terminal hydrophobic anchors of target sequence engulfed in the hydrophobic pockets of the N- and C-domain of CaM, respectively. In the light of the structural model of CaM/CaNp complex reported here, we provide new insight in the activation processes of CaN by CaM. We propose that the hydrophobic interactions between the Ca2+-saturated C-domain and C-terminal half of the target sequence provide driving forces for the initial recognition. Subsequent folding in the target sequence and structural readjustments in CaM enhance the formation of the complex and affinity to calcium. The electrostatic repulsion between CaM/CaNp complex and AID may result in the displacement of AID from active site for full activity.
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Affiliation(s)
- Chia-Lin Chyan
- Department of Chemistry, National Dong Hwa University, Hualien 974, Taiwan.
| | - Deli Irene
- Department of Chemistry, National Dong Hwa University, Hualien 974, Taiwan.
| | - Sin-Mao Lin
- Department of Chemistry, National Dong Hwa University, Hualien 974, Taiwan.
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16
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Seo HH, Lee CY, Lee J, Lim S, Choi E, Park JC, Lee S, Hwang KC. The role of nuclear factor of activated T cells during phorbol myristate acetate-induced cardiac differentiation of mesenchymal stem cells. Stem Cell Res Ther 2016; 7:90. [PMID: 27405982 PMCID: PMC4942985 DOI: 10.1186/s13287-016-0348-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 06/03/2016] [Accepted: 06/17/2016] [Indexed: 11/16/2022] Open
Abstract
Background We previously reported that phorbol 12-myristate 13-acetate (PMA) treatment can induce the cardiac differentiation of mesenchymal stem cells (MSCs). In the present study, we investigated how PMA induces cardiac differentiation of MSCs, focusing on its effect on the transcription factors responsible for increased cardiac marker gene expression. Methods Human MSCs (hMSCs) were treated with 1 μM PMA for 9 days. The expression of MSC markers and cardiac markers in the PMA-treated hMSC, as well as the nuclear translocation of transcription factors, nuclear factor of activated T cells (NFAT), and myogenic differentiation 1 (MyoD), was examined. Transcriptional activity of NFAT was examined by utilizing a green fluorescent protein (GFP) vector containing NFAT motif of human interleukin-2 promoter. The effect of PMA on the expression of key cell cycle regulators was examined. Results PMA induces the transcriptional activity of NFAT and MyoD, which have been associated with increased expression of cardiac troponin T (cTnT) and myosin heavy chain (MHC), respectively. Our data suggested that protein kinase C (PKC) mediates the effect of PMA on NFAT activation. Furthermore, PMA treatment increased cell-cycle regulator p27kip1 expression, suggesting that PMA triggers the cardiac differentiation program in MSCs by regulating key transcription factors and cell cycle regulators. Conclusions The results of this study demonstrate the importance of NFAT activation during PMA-induced MSC differentiation and help us to better understand the underlying mechanisms of small molecule-mediated MSC differentiation so that we can develop a strategy for synthesizing novel and improved differentiation-inducing small molecules. Electronic supplementary material The online version of this article (doi:10.1186/s13287-016-0348-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Hyang-Hee Seo
- Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seoul, South Korea
| | - Chang Youn Lee
- Department of Integrated Omics for Biomedical Sciences, Yonsei University, Seoul, South Korea
| | - Jiyun Lee
- Brain Korea 21 PLUS Project for Medical Science, Yonsei University, Seoul, South Korea
| | - Soyeon Lim
- Institute for Bio-medical Convergence, Catholic Kwandong University, Incheon, South Korea
| | - Eunhyun Choi
- Institute for Bio-medical Convergence, Catholic Kwandong University, Incheon, South Korea
| | - Jong-Chul Park
- Cellbiocontrol Laboratory, Department of Medical Engineering, Yonsei University College of Medicine, Seoul, South Korea
| | - Seahyoung Lee
- Institute for Bio-medical Convergence, Catholic Kwandong University, Incheon, South Korea. .,Department of Biomedical Sciences, College of Medicine, Catholic Kwandong University, Gangneung, Gangwon-do, South Korea.
| | - Ki-Chul Hwang
- Institute for Bio-medical Convergence, Catholic Kwandong University, Incheon, South Korea. .,Department of Biomedical Sciences, College of Medicine, Catholic Kwandong University, Gangneung, Gangwon-do, South Korea.
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17
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Cooperative autoinhibition and multi-level activation mechanisms of calcineurin. Cell Res 2016; 26:336-49. [PMID: 26794871 DOI: 10.1038/cr.2016.14] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Revised: 10/12/2015] [Accepted: 11/27/2015] [Indexed: 11/08/2022] Open
Abstract
The Ca(2+)/calmodulin-dependent protein phosphatase calcineurin (CN), a heterodimer composed of a catalytic subunit A and an essential regulatory subunit B, plays critical functions in various cellular processes such as cardiac hypertrophy and T cell activation. It is the target of the most widely used immunosuppressants for transplantation, tacrolimus (FK506) and cyclosporin A. However, the structure of a large part of the CNA regulatory region remains to be determined, and there has been considerable debate concerning the regulation of CN activity. Here, we report the crystal structure of full-length CN (β isoform), which revealed a novel autoinhibitory segment (AIS) in addition to the well-known autoinhibitory domain (AID). The AIS nestles in a hydrophobic intersubunit groove, which overlaps the recognition site for substrates and immunosuppressant-immunophilin complexes. Indeed, disruption of this AIS interaction results in partial stimulation of CN activity. More importantly, our biochemical studies demonstrate that calmodulin does not remove AID from the active site, but only regulates the orientation of AID with respect to the catalytic core, causing incomplete activation of CN. Our findings challenge the current model for CN activation, and provide a better understanding of molecular mechanisms of CN activity regulation.
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18
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Huang S, He Z, Zhang S, Keyhani NO, Song Y, Yang Z, Jiang Y, Zhang W, Pei Y, Zhang Y. Interplay between calcineurin and the Slt2 MAP-kinase in mediating cell wall integrity, conidiation and virulence in the insect fungal pathogen Beauveria bassiana. Fungal Genet Biol 2015; 83:78-91. [PMID: 26319315 DOI: 10.1016/j.fgb.2015.08.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2015] [Revised: 08/20/2015] [Accepted: 08/25/2015] [Indexed: 01/01/2023]
Abstract
The entomopathogenic fungus, Beauveria bassiana, is of environmental and economic importance as an insect pathogen, currently used for the biological control of a number of pests. Cell wall integrity and conidiation are critical parameters for the ability of the fungus to infect insects and for production of the infectious propagules. The contribution of calcineurin and the Slt2 MAP kinase to cell wall integrity and development in B. bassiana was investigated. Gene knockouts of either the calcineurin CNA1 subunit or the Slt2 MAP kinase resulted in decreased tolerance to calcofluor white and high temperature. In contrast, the Δcna1 strain was more tolerant to Congo red but more sensitive to osmotic stress (NaCl, sorbitol) than the wild type, whereas the Δslt2 strain had the opposite phenotype. Changes in cell wall structure and composition were seen in the Δslt2 and Δcna1 strains during growth under cell wall stress as compared to the wild type. Both Δslt2 and Δcna1 strains showed significant alterations in growth, conidiation, and viability. Elevation of intracellular ROS levels, and decreased conidial hydrophobicity and adhesion to hydrophobic surfaces, were also seen for both mutants, as well as decreased virulence. Under cell wall stress conditions, inactivation of Slt2 significantly repressed CN-mediated phosphatase activity suggesting some level of cross talk between the two pathways. Comparative transcriptome profiling of the Δslt2 and Δcna1 strains revealed alterations in the expression of distinct gene sets, with overlap in transcripts involved in cell wall integrity, stress response, conidiation and virulence. These data illustrate convergent and divergent phenotypes and targets of the calcineurin and Slt2 pathways in B. bassiana.
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Affiliation(s)
- Shuaishuai Huang
- College of Plant Protection, Biotechnology Research Center, Southwest University, Chongqing 400715, People's Republic of China
| | - Zhangjiang He
- College of Plant Protection, Biotechnology Research Center, Southwest University, Chongqing 400715, People's Republic of China
| | - Shiwei Zhang
- College of Plant Protection, Biotechnology Research Center, Southwest University, Chongqing 400715, People's Republic of China
| | - Nemat O Keyhani
- Department of Microbiology and Cell Science, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA
| | - Yulin Song
- College of Plant Protection, Biotechnology Research Center, Southwest University, Chongqing 400715, People's Republic of China
| | - Zhi Yang
- College of Plant Protection, Biotechnology Research Center, Southwest University, Chongqing 400715, People's Republic of China
| | - Yahui Jiang
- College of Plant Protection, Biotechnology Research Center, Southwest University, Chongqing 400715, People's Republic of China
| | - Wenli Zhang
- Medical Research Center, North China University of Science and Technology, Hebei 06000, People's Republic of China
| | - Yan Pei
- College of Plant Protection, Biotechnology Research Center, Southwest University, Chongqing 400715, People's Republic of China
| | - Yongjun Zhang
- College of Plant Protection, Biotechnology Research Center, Southwest University, Chongqing 400715, People's Republic of China.
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Loukin SH, Teng J, Kung C. A channelopathy mechanism revealed by direct calmodulin activation of TrpV4. Proc Natl Acad Sci U S A 2015; 112:9400-5. [PMID: 26170305 PMCID: PMC4522800 DOI: 10.1073/pnas.1510602112] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Ca(2+)-calmodulin (CaM) regulates varieties of ion channels, including Transient Receptor Potential vanilloid subtype 4 (TrpV4). It has previously been proposed that internal Ca(2+) increases TrpV4 activity through Ca(2+)-CaM binding to a C-terminal Ca(2+)-CaM binding domain (CBD). We confirmed this model by directly presenting Ca(2+)-CaM protein to membrane patches excised from TrpV4-expressing oocytes. Over 50 TRPV4 mutations are now known to cause heritable skeletal dysplasia (SD) and other diseases in human. We have previously examined 14 SD alleles and found them to all have gain-of-function effects, with the gain of constitutive open probability paralleling disease severity. Among the 14 SD alleles examined, E797K and P799L are located immediate upstream of the CBD. They not only have increase basal activity, but, unlike the wild-type or other SD-mutant channels examined, they were greatly reduced in their response to Ca(2+)-CaM. Deleting a 10-residue upstream peptide (Δ795-804) that covers the two SD mutant sites resulted in strong constitutive activity and the complete lack of Ca(2+)-CaM response. We propose that the region immediately upstream of CBD is an autoinhibitory domain that maintains the closed state through electrostatic interactions, and adjacent detachable Ca(2+)-CaM binding to CBD sterically interferes with this autoinhibition. This work further supports the notion that TrpV4 mutations cause SD by constitutive leakage. However, the closed conformation is likely destabilized by various mutations by different mechanisms, including the permanent removal of an autoinhibition documented here.
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Affiliation(s)
- Stephen H Loukin
- Laboratory of Molecular Biology, University of Wisconsin, Madison, WI 53706;
| | - Jinfeng Teng
- Laboratory of Molecular Biology, University of Wisconsin, Madison, WI 53706
| | - Ching Kung
- Laboratory of Molecular Biology, University of Wisconsin, Madison, WI 53706; Department of Genetics, University of Wisconsin, Madison, WI 53706
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20
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T cell exhaustion and Interleukin 2 downregulation. Cytokine 2015; 71:339-47. [DOI: 10.1016/j.cyto.2014.11.024] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Revised: 11/13/2014] [Accepted: 11/14/2014] [Indexed: 01/30/2023]
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21
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Dunlap TB, Guo HF, Cook EC, Holbrook E, Rumi-Masante J, Lester TE, Colbert CL, Vander Kooi CW, Creamer TP. Stoichiometry of the calcineurin regulatory domain-calmodulin complex. Biochemistry 2014; 53:5779-90. [PMID: 25144868 DOI: 10.1021/bi5004734] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Calcineurin is an essential serine/threonine phosphatase that plays vital roles in neuronal development and function, heart growth, and immune system activation. Calcineurin is unique in that it is the only phosphatase known to be activated by calmodulin in response to increasing intracellular calcium concentrations. Calcium-loaded calmodulin binds to the regulatory domain of calcineurin, resulting in a conformational change that removes an autoinhibitory domain from the active site of the phosphatase. We have determined a 1.95 Å crystal structure of calmodulin bound to a peptide corresponding to its binding region from calcineurin. In contrast to previous structures of this complex, our structure has a stoichiometry of 1:1 and has the canonical collapsed, wraparound conformation observed for many calmodulin-substrate complexes. In addition, we have used size-exclusion chromatography and time-resolved fluorescence to probe the stoichiometry of binding of calmodulin to a construct corresponding to almost the entire regulatory domain from calcineurin, again finding a 1:1 complex. Taken in sum, our data strongly suggest that a single calmodulin protein is necessary and sufficient to bind to and activate each calcineurin enzyme.
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Affiliation(s)
- Tori B Dunlap
- Center for Structural Biology, Department of Molecular and Cellular Biochemistry, University of Kentucky , 741 South Limestone Street, Lexington, Kentucky 40536-0509, United States
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22
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Kursula P. The many structural faces of calmodulin: a multitasking molecular jackknife. Amino Acids 2014; 46:2295-304. [PMID: 25005783 DOI: 10.1007/s00726-014-1795-y] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 06/22/2014] [Indexed: 12/16/2022]
Abstract
Calmodulin (CaM) is a highly conserved protein and a crucial calcium sensor in eukaryotes. CaM is a regulator of hundreds of diverse target proteins. A wealth of studies has been carried out on the structure of CaM, both in the unliganded form and in complexes with target proteins and peptides. The outcome of these studies points toward a high propensity to attain various conformational states, depending on the binding partner. The purpose of this review is to provide examples of different conformations of CaM trapped in the crystal state. In addition, comparisons are made to corresponding studies in solution. The different CaM conformations in crystal structures are also compared based on the positions of the metal ions bound to their EF hands, in terms of distances, angles, and pseudo-torsion angles. Possible caveats and artifacts in CaM crystal structures are discussed, as well as the possibilities of trapping biologically relevant CaM conformations in the crystal state.
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Affiliation(s)
- Petri Kursula
- Faculty of Biochemistry and Molecular Medicine & Biocenter Oulu, University of Oulu, Oulu, Finland,
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23
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Dunlap TB, Cook EC, Rumi-Masante J, Arvin HG, Lester TE, Creamer TP. The Distal Helix in the Regulatory Domain of Calcineurin Is Important for Domain Stability and Enzyme Function. Biochemistry 2013; 52:8643-51. [DOI: 10.1021/bi400483a] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Tori B. Dunlap
- Center for Structural Biology,
Department of Molecular and Cellular Biochemistry, University of Kentucky, 741 South Limestone Street, Lexington, Kentucky 40536-0509, United States
| | - Erik C. Cook
- Center for Structural Biology,
Department of Molecular and Cellular Biochemistry, University of Kentucky, 741 South Limestone Street, Lexington, Kentucky 40536-0509, United States
| | - Julie Rumi-Masante
- Center for Structural Biology,
Department of Molecular and Cellular Biochemistry, University of Kentucky, 741 South Limestone Street, Lexington, Kentucky 40536-0509, United States
| | - Hannah G. Arvin
- Center for Structural Biology,
Department of Molecular and Cellular Biochemistry, University of Kentucky, 741 South Limestone Street, Lexington, Kentucky 40536-0509, United States
| | - Terrence E. Lester
- Center for Structural Biology,
Department of Molecular and Cellular Biochemistry, University of Kentucky, 741 South Limestone Street, Lexington, Kentucky 40536-0509, United States
| | - Trevor P. Creamer
- Center for Structural Biology,
Department of Molecular and Cellular Biochemistry, University of Kentucky, 741 South Limestone Street, Lexington, Kentucky 40536-0509, United States
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