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Zhang X, Liang W, Zheng G, Li B. Decoding the deactivation mechanism of R192W mutation of ZAP-70 using molecular dynamics simulations and binding free energy calculations. J Mol Model 2023; 29:371. [PMID: 37953318 DOI: 10.1007/s00894-023-05771-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Accepted: 10/25/2023] [Indexed: 11/14/2023]
Abstract
CONTEXT ZAP-70 (zeta-chain-associated protein of 70 kDa), serving as a critical regulator for T cell antigen receptor signaling, represents an attractive therapeutic target for autoimmunity disease. How the mechanistical mechanism of ZAP-70 to a human autoimmune syndrome-associated R192W mutation remains unclear. The results indicated that the R192W mutation of ZAP-70 clearly affected the conformational flexibility of the N-terminal ITAM-Y2P. Structural analysis unveiled that the R192W mutation of ZAP-70 caused the exposure of the N-terminal ITAM-Y2P to the solvent. MM-GBSA binding free energy calculations exhibited that the R192W mutation decreased the binding affinity of ITAM-Y2P to the ZAP-70 mutant. Residue-based free energy decomposition further revealed that the protein-peptide interaction networks involving electrostatic interactions provide significant contributions for complex formation. The energy unfavorable residues include Arg43, Arg192, Tyr240, and Lys244 from ZAP-70 and Asn301, Leu303, pY304, and pY315 from ITAM-Y2P in the R192W mutant. Our obtained results may help the understanding of the deactivation mechanism of ZAP-70 induced by the R192W mutation. METHODS In the work, multiple replica molecular dynamics simulations and molecular mechanics-generalized Born surface area (MM-GBSA) method were performed to reveal the doubly phosphorylated ITAMs (ITAM-Y2P)-mediated deactivation mechanism of ZAP-70 induced by the R192W mutation.
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Affiliation(s)
- Xuehua Zhang
- Suzhou Hospital, Affiliated Hospital of Medical School, Nanjing University, Suzhou, China
| | - Wenqi Liang
- Department of Emergency, Changhai Hospital, The First Affiliated Hospital of Naval Medical University, Shanghai, 200433, China
| | - Guodong Zheng
- Department of VIP Clinic, Changhai Hospital, The First Affiliated Hospital to Naval Medical University, Shanghai, 200433, China.
| | - Bei Li
- Department of VIP Clinic, Changhai Hospital, The First Affiliated Hospital to Naval Medical University, Shanghai, 200433, China.
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Xiu CD, Ying LX, Chun HY, Fu LJ. Advances in CD247. Scand J Immunol 2022; 96:e13170. [PMID: 35388926 DOI: 10.1111/sji.13170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 03/27/2022] [Accepted: 04/04/2022] [Indexed: 11/27/2022]
Abstract
CD247, which is also known as CD3ζ, CD3H, CD3Q, CD3Z, IMD25, T3Z, and TCRZ, encodes CD3ζ protein, which is expressed primarily in natural killer (NK) and T cells. Since the discovery of the ζ peptide in 1986, it has been continuously investigated. In this paper, we review the composition, molecular mechanisms and regulatory factors of CD247 expression in T cells; and review the autoimmune diseases, tumors and inflammatory diseases associated with CD247, providing a detailed and comprehensive reference for further research on the mechanism of CD247 and related diseases.
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Affiliation(s)
- Chen De Xiu
- Department of Critical Care Medicine, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan, China
| | - Lei Xian Ying
- Department of Critical Care Medicine, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan, China
| | - Hu Ying Chun
- Department of Emergency Medicine, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan, China
| | - Li Jia Fu
- Department of Cardiology, The Affiliated Hospital of Southwest Medical University, Key Laboratory of Medical Electrophysiology, Ministry of Education, Luzhou, Sichuan, China
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3
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An allosteric hot spot in the tandem-SH2 domain of ZAP-70 regulates T-cell signaling. Biochem J 2020; 477:1287-1308. [PMID: 32203568 DOI: 10.1042/bcj20190879] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 03/18/2020] [Accepted: 03/23/2020] [Indexed: 12/28/2022]
Abstract
T-cell receptor (TCR) signaling is initiated by recruiting ZAP-70 to the cytosolic part of TCR. ZAP-70, a non-receptor tyrosine kinase, is composed of an N-terminal tandem SH2 (tSH2) domain connected to the C-terminal kinase domain. The ZAP-70 is recruited to the membrane through binding of tSH2 domain and the doubly phosphorylated ITAM motifs of CD3 chains in the TCR complex. Our results show that the tSH2 domain undergoes a biphasic structural transition while binding to the doubly phosphorylated ITAM-ζ1 peptide. The C-terminal SH2 domain binds first to the phosphotyrosine residue of ITAM peptide to form an encounter complex leading to subsequent binding of second phosphotyrosine residue to the N-SH2 domain. We decipher a network of noncovalent interactions that allosterically couple the two SH2 domains during binding to doubly phosphorylated ITAMs. Mutation in the allosteric network residues, for example, W165C, uncouples the formation of encounter complex to the subsequent ITAM binding thus explaining the altered recruitment of ZAP-70 to the plasma membrane causing autoimmune arthritis in mice. The proposed mechanism of allosteric coupling is unique to ZAP-70, which is fundamentally different from Syk, a close homolog of ZAP-70 expressed in B-cells.
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Chan AY, Punwani D, Kadlecek TA, Cowan MJ, Olson JL, Mathes EF, Sunderam U, Fu SM, Srinivasan R, Kuriyan J, Brenner SE, Weiss A, Puck JM. A novel human autoimmune syndrome caused by combined hypomorphic and activating mutations in ZAP-70. J Exp Med 2016; 213:155-65. [PMID: 26783323 PMCID: PMC4749924 DOI: 10.1084/jem.20150888] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Accepted: 12/14/2015] [Indexed: 12/31/2022] Open
Abstract
Chan et al. describe a combination of alleles with hypomorphic and activating mutations in the T cell signaling molecule ZAP-70 in a patient with autoimmunity. A brother and sister developed a previously undescribed constellation of autoimmune manifestations within their first year of life, with uncontrollable bullous pemphigoid, colitis, and proteinuria. The boy had hemophilia due to a factor VIII autoantibody and nephrotic syndrome. Both children required allogeneic hematopoietic cell transplantation (HCT), which resolved their autoimmunity. The early onset, severity, and distinctive findings suggested a single gene disorder underlying the phenotype. Whole-exome sequencing performed on five family members revealed the affected siblings to be compound heterozygous for two unique missense mutations in the 70-kD T cell receptor ζ-chain associated protein (ZAP-70). Healthy relatives were heterozygous mutation carriers. Although pre-HCT patient T cells were not available, mutation effects were determined using transfected cell lines and peripheral blood from carriers and controls. Mutation R192W in the C-SH2 domain exhibited reduced binding to phosphorylated ζ-chain, whereas mutation R360P in the N lobe of the catalytic domain disrupted an autoinhibitory mechanism, producing a weakly hyperactive ZAP-70 protein. Although human ZAP-70 deficiency can have dysregulated T cells, and autoreactive mouse thymocytes with weak Zap-70 signaling can escape tolerance, our patients’ combination of hypomorphic and activating mutations suggested a new disease mechanism and produced previously undescribed human ZAP-70–associated autoimmune disease.
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Affiliation(s)
- Alice Y Chan
- Department of Pediatrics, University of California San Francisco School of Medicine, San Francisco, CA 94143
| | - Divya Punwani
- Department of Pediatrics, University of California San Francisco School of Medicine, San Francisco, CA 94143
| | - Theresa A Kadlecek
- Department of Medicine, Rosalind Russell and Ephraim Engleman Rheumatology Research Center and Howard Hughes Medical Institute, University of California San Francisco School of Medicine, San Francisco, CA 94143
| | - Morton J Cowan
- Department of Pediatrics, University of California San Francisco School of Medicine, San Francisco, CA 94143
| | - Jean L Olson
- Department of Pathology, University of California San Francisco School of Medicine, San Francisco, CA 94143
| | - Erin F Mathes
- Department of Pediatrics, University of California San Francisco School of Medicine, San Francisco, CA 94143 Department of Dermatology, University of California San Francisco School of Medicine, San Francisco, CA 94143
| | - Uma Sunderam
- Innovation Labs, Tata Consulting Services, Hyderabad 50019, Telangana, India
| | - Shu Man Fu
- Department of Medicine, University of Virginia School of Medicine, Charlottesville, VA 22908
| | - Rajgopal Srinivasan
- Innovation Labs, Tata Consulting Services, Hyderabad 50019, Telangana, India
| | - John Kuriyan
- Department of Molecular and Cell Biology and Department of Chemistry, California Institute of Quantitative Biosciences and Howard Hughes Medical Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, University of California, Berkeley, Berkeley, CA 94720
| | - Steven E Brenner
- Department of Plant and Microbial Biology, University of California, Berkeley, Berkeley, CA 94720
| | - Arthur Weiss
- Department of Medicine, Rosalind Russell and Ephraim Engleman Rheumatology Research Center and Howard Hughes Medical Institute, University of California San Francisco School of Medicine, San Francisco, CA 94143
| | - Jennifer M Puck
- Department of Pediatrics, University of California San Francisco School of Medicine, San Francisco, CA 94143
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Bond PJ, Faraldo-Gómez JD. Molecular mechanism of selective recruitment of Syk kinases by the membrane antigen-receptor complex. J Biol Chem 2011; 286:25872-81. [PMID: 21602568 DOI: 10.1074/jbc.m111.223321] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
ZAP-70 and Syk are essential tyrosine kinases in intracellular immunological signaling. Both contain an inhibitory SH2 domain tandem, which assembles onto the catalytic domain. Upon binding to doubly phosphorylated ITAM motifs on activated antigen receptors, the arrangement of the SH2 domains changes. From available structures, this event is not obviously conducive to dissociation of the autoinhibited complex, yet it ultimately translates into kinase activation through a mechanism not yet understood. We present a comprehensive theoretical study of this molecular mechanism, using atomic resolution simulations and free-energy calculations, totaling >10 μs of simulation time. Through these, we dissect the microscopic mechanism coupling stepwise ITAM engagement and SH2 tandem structural change and reveal key differences between ZAP-70 and Syk. Importantly, we show that a subtle conformational bias in the inter-SH2 connector causes ITAM to bind preferentially to kinase-dissociated tandems. We thus propose that phosphorylated antigen receptors selectively recruit kinases that are uninhibited and that the resulting population shift in the membrane vicinity sustains signal transduction.
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Affiliation(s)
- Peter J Bond
- Max Planck Institute of Biophysics and the Cluster of Excellence Macromolecular Complexes, 60438 Frankfurt am Main, Germany
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Imaging T-cell receptor activation reveals accumulation of tyrosine-phosphorylated CD3ζ in the endosomal compartment. Proc Natl Acad Sci U S A 2010; 107:22128-33. [PMID: 21135224 DOI: 10.1073/pnas.1016388108] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Phosphorylation of the T-cell receptor complex (TcR/CD3) mediates the survival and antigen-induced activation of T cells. TcR/CD3 phosphorylation is usually monitored using phospho-specific antibodies, which precludes dynamic measurements. Here, we have developed genetically encoded, live-cell reporters that enable simultaneous monitoring of the phosphorylation state and intracellular trafficking of CD3ζ, the major signal-transducing subunit of the TcR/CD3. We show that these reporters provide accurate readouts of TcR/CD3 phosphorylation and are sensitive to the local balance of kinase and phosphatase activities acting upon TcR/CD3. Using these reporters, we demonstrate that, in addition to the expected activation-dependent phosphorylation at the plasma membrane, tyrosine-phosphorylated CD3ζ accumulates on endosomal vesicles distinct from lysosomes. These results suggest that an intracellular pool of phosphorylated CD3ζ may help to sustain TcR/CD3 signaling after the receptor internalization.
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Zloh M, Esposito D, Gibbons WA. Spectroscopy-Based Modelling of the 3D Structure of the β Subunit of the High Affinity IgE Receptor. MOLECULAR SIMULATION 2006. [DOI: 10.1080/08927020008022386] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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8
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Abstract
In this chapter, we have described the biophysical investigations which have dissected the mechanisms of SH2 domain function. Due to nearly a decade and a half of investigation on SH2 domains, much about their binding mechanism has been characterized. SH2 domains have been found to have a positively charged binding cavity, largely conserved between different SH2 domains, which coordinates binding of the pTyr in the target. The ionic interactions between this pocket and the pTyr, in particular, between Arg beta B5 and the phosphate, provide the majority of the binding energy stabilizing SH2 domain-target interactions. The specificity in SH2 domain-target interactions emanates most often from the interactions between the residues C-terminal to the pTyr in the target and the specificity determining residues in the C-terminal half of the SH2 domain. However, the interactions in the specificity determining region of SH2 domains are weak, and hence single SH2 domains show only a modest level of specificity for tyrosine phosphorylated targets. Greater specificity in SH2 domain-containing protein-tyrosine phosphorylated target interactions can be achieved by placing SH2 domains in tandem (as is often found) or possibly through specific localization of SH2 domain-containing proteins within the cell. Although a relatively good understanding of how SH2 domains function in isolation has been obtained, the ways in which SH2 domain binding is coupled to allosteric transmission of signals in larger SH2 domain-containing proteins are still not clear. Hence, the future should bring further investigations of the mechanisms by which SH2 domain ligation alters the enzymatic activity and cellular localization of SH2 domain-containing proteins.
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Affiliation(s)
- J Michael Bradshaw
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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9
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Folmer RHA, Geschwindner S, Xue Y. Crystal structure and NMR studies of the apo SH2 domains of ZAP-70: two bikes rather than a tandem. Biochemistry 2002; 41:14176-84. [PMID: 12450381 DOI: 10.1021/bi026465e] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The protein kinase ZAP-70 is involved in T-cell activation, and interacts with tyrosine-phosphorylated peptide sequences known as immunoreceptor tyrosine activation motifs (ITAMs), which are present in three of the subunits of the T-cell receptor. We have studied the tandem SH2 (tSH2) domains of ZAP-70, by both X-ray and NMR. Here, we present the crystal structure of the apoprotein, i.e., the tSH2 domain in the absence of ITAM. Comparison with the previously reported complex structure reveals that binding to the ITAM peptide induces surprisingly large movements between the two SH2 domains and within the actual binding sites. The conformation of the ITAM-free protein is partly governed by a hydrophobic cluster between the linker region and the C-terminal SH2 domain. Our data suggest that the two SH2 domains are able to undergo large interdomain movements. The proposed relative flexibility of the SH2 domains is further supported by the finding that no NMR signals could be detected for the two helices connecting the SH2 domains; these are likely to be broadened beyond detection due to conformational exchange. It is likely that this conformational reorientation induced by ITAM binding is the main signaling event activating the kinase domain in ZAP-70. Another NMR observation was that the N-terminal SH2 domain could bind tetrapeptides derived from the ITAM sequence, apparently without the need to interact with the C-terminal domain. In contrast, the C-terminal domain has little affinity for tetrapeptides. The opposite situation is true for binding to plain phosphotyrosine, where the C-terminal domain has a higher affinity. Distinct features in the crystal structure, showing the interdependence of both domains, explain these binding data.
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Affiliation(s)
- Rutger H A Folmer
- Structural Chemistry Laboratory, AstraZeneca R&D Mölndal, S-431 83 Mölndal, Sweden
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10
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Aandahl EM, Moretto WJ, Haslett PA, Vang T, Bryn T, Tasken K, Nixon DF. Inhibition of antigen-specific T cell proliferation and cytokine production by protein kinase A type I. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2002; 169:802-8. [PMID: 12097383 DOI: 10.4049/jimmunol.169.2.802] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
cAMP inhibits biochemical events leading to T cell activation by triggering of an inhibitory protein kinase A (PKA)-C-terminal Src kinase pathway assembled in lipid rafts. In this study, we demonstrate that activation of PKA type I by Sp-8-bromo-cAMPS (a cAMP agonist) has profound inhibitory effects on Ag-specific immune responses in peripheral effector T cells. Activation of PKA type I inhibits both cytokine production and proliferative responses in both CD4(+) and CD8(+) T cells in a concentration-dependent manner. The observed effects of cAMP appeared to occur endogenously in T cells and were not dependent on APC. The inhibition of responses was not due to apoptosis of specific T cells and was reversible by a PKA type I-selective cAMP antagonist. This supports the notion of PKA type I as a key enzyme in the negative regulation of immune responses and a potential target for inhibiting autoreactive T cells.
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Affiliation(s)
- Einar Martin Aandahl
- Gladstone Institute of Virology and Immunology, University of California, San Francisco, CA 94141, USA.
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11
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Abstract
In conclusion, multiple receptors and signal transduction cascades influence T-cell function and fate. During the past few years many of these important aspects of T-cell biology were identified. The complexity of the various signaling pathways has made appreciation of their clinical significance difficult. One way of studying the function of these molecules is to create mice deficient of these components. However, frequently the murine phenotype is far from reflecting the homologous human deficiency. It is therefore beneficial to define the human immunodeficiencies in order to understand the role of a certain signaling molecule in humans. Further, mutations that result in partial deficiencies may result in a different phenotype from null mutations. This information may aid in improving structure/function analysis of these signaling components.
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Affiliation(s)
- E Grunebaum
- IIIR Program, Research Institute, Hospital for Sick Children and The University of Toronto, Canada
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12
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O'Brien R, Rugman P, Renzoni D, Layton M, Handa R, Hilyard K, Waterfield MD, Driscoll PC, Ladbury JE. Alternative modes of binding of proteins with tandem SH2 domains. Protein Sci 2000; 9:570-9. [PMID: 10752619 PMCID: PMC2144564 DOI: 10.1110/ps.9.3.570] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The issue of specificity in tyrosine kinase intracellular signaling mediated by src homology 2 (SH2) domains has great importance in the understanding how individual signals maintain their mutual exclusivity and affect downstream responses. Several proteins contain tandem SH2 domains that, on interacting with their ligand, provide a higher level of specificity than can be afforded by the interaction of a single SH2 domain. In this study, we focus on the comparison of two proteins ZAP70 and the p85 subunit of PI 3-kinase, which although distinctly different in function and general structure, possess tandem SH2 domains separated by a linker region and which bind to phosphorylated receptor molecules localized to the cell membrane. Binding studies using isothermal titration calorimetry show that these two proteins interact with peptides mimicking their physiological ligands in very different ways. In the case of the SH2 domains from ZAP70, they interact with a stoichiometry of unity, while p85 is able to make two distinct interactions, one with a stoichiometry of 1:1 and the other with two p85 molecules interacting with one receptor. The observation of two different modes of binding of p85 might be important in providing different cellular responses based on fluctuating intracellular concentration regimes of this protein. Thermodynamic data on both proteins suggest that a conformational change occurs on binding. On investigation of this structural change using a truncated form of p85 (including just the two SH2 domains and the inter-SH2 region), both NMR and circular dichroism spectroscopic studies failed to show significant changes in secondary structure. This suggests that any conformational change associated with binding is small and potentially limited to loop regions of the protein.
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Affiliation(s)
- R O'Brien
- Department of Biochemistry and Molecular Biology, University College London, United Kingdom
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13
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Sharie N, Arpaia E, Roifman CM. CD8 LYMPHOCYTOPENIA CAUSED BY ZAP-70 DEFICIENCY. Radiol Clin North Am 2000. [DOI: 10.1016/s0033-8389(22)00180-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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14
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Sharfe N, Arpaia E, Roifman CM. CD8 LYMPHOCYTOPENIA CAUSED BY ZAP-70 DEFICIENCY. Immunol Allergy Clin North Am 2000. [DOI: 10.1016/s0889-8561(05)70135-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Wong J, Straus D, Chan AC. Genetic evidence of a role for Lck in T-cell receptor function independent or downstream of ZAP-70/Syk protein tyrosine kinases. Mol Cell Biol 1998; 18:2855-66. [PMID: 9566904 PMCID: PMC110664 DOI: 10.1128/mcb.18.5.2855] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/1997] [Accepted: 02/13/1998] [Indexed: 02/07/2023] Open
Abstract
T-cell antigen receptor (TCR) engagement results in sequential activation of the Src protein tyrosine kinases (PTKs) Lck and Fyn and the Syk PTKs, ZAP-70 and Syk. While the Src PTKs mediate the phosphorylation of TCR-associated signaling subunits and the phosphorylation and activation of the Syk PTKs, the lack of a constitutively active Syk PTK has prohibited the analysis of Lck function downstream of these initiating signaling events. We describe here the generation of an activated Syk family PTK by substituting the kinase domain of Syk for the homologous region in ZAP-70 (designated as KS for kinase swap). Expression of the KS chimera resulted in its autophosphorylation, the phosphorylation of cellular proteins, the upregulation of T-cell activation markers, and the induction of interleukin-2 gene synthesis in a TCR-independent fashion. The KS chimera and downstream ZAP-70 or Syk substrates, such as SLP-76, were still phosphorylated when expressed in Lck-deficient JCaM1.6 T cells. However, expression of the KS chimera in JCaM1.6 cells failed to rescue downstream signaling events, demonstrating a functional role for Lck beyond the activation of the ZAP-70 and Syk PTKs. These results indicate that downstream TCR signaling pathways may be differentially regulated by ZAP-70 and Lck PTKs and provide a mechanism by which effector functions may be selectively activated in response to TCR stimulation.
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Affiliation(s)
- J Wong
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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