1
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Wu R, Lim MS. Updates in pathobiological aspects of anaplastic large cell lymphoma. Front Oncol 2023; 13:1241532. [PMID: 37810974 PMCID: PMC10556522 DOI: 10.3389/fonc.2023.1241532] [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: 06/16/2023] [Accepted: 09/04/2023] [Indexed: 10/10/2023] Open
Abstract
Anaplastic large cell lymphomas (ALCL) encompass several distinct subtypes of mature T-cell neoplasms that are unified by the expression of CD30 and anaplastic cytomorphology. Identification of the cytogenetic abnormality t(2;5)(p23;q35) led to the subclassification of ALCLs into ALK+ ALCL and ALK- ALCL. According to the most recent World Health Organization (WHO) Classification of Haematolymphoid Tumours as well as the International Consensus Classification (ICC) of Mature Lymphoid Neoplasms, ALCLs encompass ALK+ ALCL, ALK- ALCL, and breast implant-associated ALCL (BI-ALCL). Approximately 80% of systemic ALCLs harbor rearrangement of ALK, with NPM1 being the most common partner gene, although many other fusion partner genes have been identified to date. ALK- ALCLs represent a heterogeneous group of lymphomas with distinct clinical, immunophenotypic, and genetic features. A subset harbor recurrent rearrangement of genes, including TYK2, DUSP22, and TP63, with a proportion for which genetic aberrations have yet to be characterized. Although primary cutaneous ALCL (pc-ALCL) is currently classified as a subtype of primary cutaneous T-cell lymphoma, due to the large anaplastic and pleomorphic morphology together with CD30 expression in the malignant cells, this review also discusses the pathobiological features of this disease entity. Genomic and proteomic studies have contributed significant knowledge elucidating novel signaling pathways that are implicated in ALCL pathogenesis and represent candidate targets of therapeutic interventions. This review aims to offer perspectives on recent insights regarding the pathobiological and genetic features of ALCL.
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Affiliation(s)
| | - Megan S. Lim
- Department of Pathology and Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, United States
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2
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Hallumi E, Shalah R, Lo WL, Corso J, Oz I, Beach D, Wittman S, Isenberg A, Sela M, Urlaub H, Weiss A, Yablonski D. Itk Promotes the Integration of TCR and CD28 Costimulation through Its Direct Substrates SLP-76 and Gads. THE JOURNAL OF IMMUNOLOGY 2021; 206:2322-2337. [PMID: 33931484 DOI: 10.4049/jimmunol.2001053] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Accepted: 03/15/2021] [Indexed: 11/19/2022]
Abstract
The costimulatory receptor CD28 synergizes with the TCR to promote IL-2 production, cell survival, and proliferation; yet the obligatory interdependence of TCR and CD28 signaling is not well understood. Upon TCR stimulation, Gads, a Grb2-family adaptor, bridges the interaction of two additional adaptors, LAT and SLP-76, to form a TCR-induced effector signaling complex. SLP-76 binds the Tec-family tyrosine kinase, Itk, which phosphorylates SLP-76 Y173 and PLC-γ1 Y783. In this study, we identified TCR-inducible, Itk-mediated phosphorylation of Gads Y45 in a human T cell line and in mouse primary T cells. Y45 is found within the N-terminal SH3 domain of Gads, an evolutionarily conserved domain with no known signaling function. Gads Y45 phosphorylation depended on the interaction of Gads with SLP-76 and on the dimerization-dependent binding of Gads to phospho-LAT. We provide evidence that Itk acts through SLP-76 and Gads to promote the TCR/CD28-induced activation of the RE/AP transcriptional element from the IL-2 promoter. Two Itk-related features of SLP-76, Y173 and a proline-rich Itk SH3 binding motif on SLP-76, were dispensable for activation of NFAT but selectively required for the TCR/CD28-induced increase in cytoplasmic and nuclear c-Rel and consequent RE/AP activation. We provide evidence that unphosphorylated, monomeric Gads mediates an RE/AP-directed inhibitory activity that is mitigated upon Gads dimerization and Y45 phosphorylation. This study illuminates a new, to our knowledge, regulatory module, in which TCR-induced, Itk-mediated phosphorylation sites on SLP-76 and Gads control the transcriptional response to TCR/CD28 costimulation, thus enforcing the obligatory interdependence of the TCR and CD28 signaling pathways.
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Affiliation(s)
- Enas Hallumi
- Department of Immunology, Ruth and Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel
| | - Rose Shalah
- Department of Immunology, Ruth and Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel
| | - Wan-Lin Lo
- Rosalind Russell and Ephraim P. Engleman Arthritis Research Center, Division of Rheumatology, Department of Medicine, University of California, San Francisco, San Francisco, CA
| | - Jasmin Corso
- Bioanalytical Mass Spectrometry Group, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Ilana Oz
- Department of Immunology, Ruth and Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel
| | - Dvora Beach
- Department of Immunology, Ruth and Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel
| | - Samuel Wittman
- Department of Immunology, Ruth and Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel
| | - Amy Isenberg
- Department of Immunology, Ruth and Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel
| | - Meirav Sela
- Department of Immunology, Ruth and Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel
| | - Henning Urlaub
- Bioanalytical Mass Spectrometry Group, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany.,Bioanalytics Research Group, Institute for Clinical Chemistry, University Medical Center Göttingen, Göttingen, Germany
| | - Arthur Weiss
- Rosalind Russell and Ephraim P. Engleman Arthritis Research Center, Division of Rheumatology, Department of Medicine, University of California, San Francisco, San Francisco, CA.,Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, CA
| | - Deborah Yablonski
- Department of Immunology, Ruth and Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel
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3
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Lev A, Lee YN, Sun G, Hallumi E, Simon AJ, Zrihen KS, Levy S, Beit Halevi T, Papazian M, Shwartz N, Somekh I, Levy-Mendelovich S, Wolach B, Gavrieli R, Vernitsky H, Barel O, Javasky E, Stauber T, Ma CA, Zhang Y, Amariglio N, Rechavi G, Hendel A, Yablonski D, Milner JD, Somech R. Inherited SLP76 deficiency in humans causes severe combined immunodeficiency, neutrophil and platelet defects. J Exp Med 2020; 218:211562. [PMID: 33231617 PMCID: PMC7690938 DOI: 10.1084/jem.20201062] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Revised: 09/06/2020] [Accepted: 10/08/2020] [Indexed: 12/30/2022] Open
Abstract
The T cell receptor (TCR) signaling pathway is an ensemble of numerous proteins that are crucial for an adequate immune response. Disruption of any protein involved in this pathway leads to severe immunodeficiency and unfavorable clinical outcomes. Here, we describe an infant with severe immunodeficiency who was found to have novel biallelic mutations in SLP76. SLP76 is a key protein involved in TCR signaling and in other hematopoietic pathways. Previous studies of this protein were performed using Jurkat-derived human leukemic T cell lines and SLP76-deficient mice. Our current study links this gene, for the first time, to a human immunodeficiency characterized by early-onset life-threatening infections, combined T and B cell immunodeficiency, severe neutrophil defects, and impaired platelet aggregation. Hereby, we characterized aspects of the patient's immune phenotype, modeled them with an SLP76-deficient Jurkat-derived T cell line, and rescued some consequences using ectopic expression of wild-type SLP76. Understanding human diseases due to SLP76 deficiency is helpful in explaining the mixed T cell and neutrophil defects, providing a guide for exploring human SLP76 biology.
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Affiliation(s)
- Atar Lev
- Pediatric Department A and Immunology Service, Jeffrey Modell Foundation Center, Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Tel Hashomer, Israel.,The Mina and Everard Goodman Faculty of Life Sciences, Advanced Materials and Nanotechnology Institute, Bar-Ilan University, Ramat Gan, Israel
| | - Yu Nee Lee
- Pediatric Department A and Immunology Service, Jeffrey Modell Foundation Center, Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Tel Hashomer, Israel
| | - Guangping Sun
- Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD
| | - Enas Hallumi
- Department of Immunology, Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel
| | - Amos J Simon
- Pediatric Department A and Immunology Service, Jeffrey Modell Foundation Center, Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Tel Hashomer, Israel.,Division of Haematology and Bone Marrow Transplantation, Sheba Medical Center, Tel Hashomer, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Keren S Zrihen
- Pediatric Department A and Immunology Service, Jeffrey Modell Foundation Center, Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Tel Hashomer, Israel
| | - Shiran Levy
- Pediatric Department A and Immunology Service, Jeffrey Modell Foundation Center, Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Tel Hashomer, Israel
| | - Tal Beit Halevi
- Pediatric Department A and Immunology Service, Jeffrey Modell Foundation Center, Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Tel Hashomer, Israel
| | - Maria Papazian
- Pediatric Department A and Immunology Service, Jeffrey Modell Foundation Center, Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Tel Hashomer, Israel
| | - Neta Shwartz
- Pediatric Department A and Immunology Service, Jeffrey Modell Foundation Center, Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Tel Hashomer, Israel
| | - Ido Somekh
- Department of Pediatric Hematology Oncology, Schneider Children's Medical Center of Israel, Petah Tikva, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Sarina Levy-Mendelovich
- The Israeli National Hemophilia Center and Thrombosis Unit, The Amalia Biron Research Institute of Thrombosis and Hemostasis, Sheba Medical Center, Tel Hashomer, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Baruch Wolach
- Department of Pediatrics and Laboratory for Leukocyte Function, Meir Medical Center, Kfar Saba, Israel
| | - Ronit Gavrieli
- Department of Pediatrics and Laboratory for Leukocyte Function, Meir Medical Center, Kfar Saba, Israel
| | - Helly Vernitsky
- Division of Haematology and Bone Marrow Transplantation, Sheba Medical Center, Tel Hashomer, Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Ortal Barel
- The Genomic Unit, Sheba Cancer Research Center, Sheba Medical Center, Tel Hashomer, Israel.,Cancer Research Center, Wohl Institute for Translational Medicine, Sheba Medical Center, Tel Hashomer, Israel
| | - Elisheva Javasky
- The Genomic Unit, Sheba Cancer Research Center, Sheba Medical Center, Tel Hashomer, Israel.,Cancer Research Center, Wohl Institute for Translational Medicine, Sheba Medical Center, Tel Hashomer, Israel
| | - Tali Stauber
- Pediatric Department A and Immunology Service, Jeffrey Modell Foundation Center, Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Tel Hashomer, Israel
| | - Chi A Ma
- Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD
| | - Yuan Zhang
- Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD.,Department of Pediatrics, Columbia University Irving Medical Center, New York, NY
| | - Ninette Amariglio
- The Mina and Everard Goodman Faculty of Life Sciences, Advanced Materials and Nanotechnology Institute, Bar-Ilan University, Ramat Gan, Israel.,Cancer Research Center, Sheba Medical Center, Tel Hashomer, Ramat Gan, Israel
| | - Gideon Rechavi
- Cancer Research Center, Wohl Institute for Translational Medicine, Sheba Medical Center, Tel Hashomer, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Ayal Hendel
- The Mina and Everard Goodman Faculty of Life Sciences, Advanced Materials and Nanotechnology Institute, Bar-Ilan University, Ramat Gan, Israel
| | - Deborah Yablonski
- Department of Immunology, Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel
| | - Joshua D Milner
- Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD.,Department of Pediatrics, Columbia University Irving Medical Center, New York, NY
| | - Raz Somech
- Pediatric Department A and Immunology Service, Jeffrey Modell Foundation Center, Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Tel Hashomer, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
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4
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Wang QL, Liang JQ, Gong BN, Xie JJ, Yi YT, Lan X, Li Y. T Cell Receptor (TCR)-Induced PLC-γ1 Sumoylation via PIASxβ and PIAS3 SUMO E3 Ligases Regulates the Microcluster Assembly and Physiological Function of PLC-γ1. Front Immunol 2019; 10:314. [PMID: 30873169 PMCID: PMC6403162 DOI: 10.3389/fimmu.2019.00314] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 02/06/2019] [Indexed: 11/16/2022] Open
Abstract
The SUMO modification system plays an important role in T cell activation, yet how sumoylation regulates TCR-proximal signaling remains largely unknown. We show here that Phospholipase C-γ1 (PLC-γ1) is conjugated by SUMO1 at K54 and K987 upon TCR stimulation and that K54 sumoylation is pivotal for PLC-γ1-mediated T cell activation. We further demonstrate that TCR-induced K54 sumoylation of PLC-γ1 significantly promotes the formation of PLC-γ1 microclusters and the association of PLC-γ1 with the adaptor proteins SLP76 and Gads, but only slightly affects the phosphorylation of PLC-γ1 on Y783, which determines the enzyme catalytic activity. Moreover, upon TCR stimulation, the SUMO E3 ligases PIASxβ and PIAS3 both interact with PLC-γ1 and cooperate to sumoylate PLC-γ1, facilitating the assembly of PLC-γ1 microclusters. Together, our findings reveal a critical role of PLC-γ1 K54 sumoylation in PLC-γ1 microcluster assembly that controls PLC-γ1-mediated T cell activation, suggesting that sumoylation may have an important role in the microcluster assembly of TCR-proximal signaling proteins.
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Affiliation(s)
- Qi-Long Wang
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, China.,School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Jia-Qi Liang
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, China.,School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Bei-Ni Gong
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, China.,School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Ji-Ji Xie
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, China.,School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Yu-Ting Yi
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, China.,School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Xin Lan
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, China.,School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Yingqiu Li
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory of Biocontrol, Sun Yat-sen University, Guangzhou, China.,School of Life Sciences, Sun Yat-sen University, Guangzhou, China
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5
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Belmont J, Gu T, Mudd A, Salomon AR. A PLC-γ1 Feedback Pathway Regulates Lck Substrate Phosphorylation at the T-Cell Receptor and SLP-76 Complex. J Proteome Res 2017. [PMID: 28644030 DOI: 10.1021/acs.jproteome.6b01026] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Phospholipase C gamma 1 (PLC-γ1) occupies a critically important position in the T-cell signaling pathway. While its functions as a regulator of both Ca2+ signaling and PKC-family kinases are well characterized, PLC-γ1's role in the regulation of early T-cell receptor signaling events is incompletely understood. Activation of the T-cell receptor leads to the formation of a signalosome complex between SLP-76, LAT, PLC-γ1, Itk, and Vav1. Recent studies have revealed the existence of both positive and negative feedback pathways from SLP-76 to the apical kinase in the pathway, Lck. To determine if PLC-γ1 contributes to the regulation of these feedback networks, we performed a quantitative phosphoproteomic analysis of PLC-γ1-deficient T cells. These data revealed a previously unappreciated role for PLC-γ1 in the positive regulation of Zap-70 and T-cell receptor tyrosine phosphorylation. Conversely, PLC-γ1 negatively regulated the phosphorylation of SLP-76-associated proteins, including previously established Lck substrate phosphorylation sites within this complex. While the positive and negative regulatory phosphorylation sites on Lck were largely unchanged, Tyr192 phosphorylation was elevated in Jgamma1. The data supports a model wherein Lck's targeting, but not its kinase activity, is altered by PLC-γ1, possibly through Lck Tyr192 phosphorylation and increased association of the kinase with protein scaffolds SLP-76 and TSAd.
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Affiliation(s)
- Judson Belmont
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University , Providence, Rhode Island 02912, United States
| | - Tao Gu
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University , Providence, Rhode Island 02912, United States
| | - Ashley Mudd
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University , Providence, Rhode Island 02912, United States
| | - Arthur R Salomon
- Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University , Providence, Rhode Island 02912, United States.,Department of Chemistry, Brown University , Providence, Rhode Island 02912, United States
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6
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Bilal MY, Zhang EY, Dinkel B, Hardy D, Yankee TM, Houtman JCD. GADS is required for TCR-mediated calcium influx and cytokine release, but not cellular adhesion, in human T cells. Cell Signal 2015; 27:841-50. [PMID: 25636200 DOI: 10.1016/j.cellsig.2015.01.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Revised: 01/07/2015] [Accepted: 01/21/2015] [Indexed: 11/16/2022]
Abstract
GRB2 related adaptor protein downstream of Shc (GADS) is a member of the GRB2 family of adaptors and is critical for TCR-induced signaling. The current model is that GADS recruits SLP-76 to the LAT complex, which facilitates the phosphorylation of SLP-76, the activation of PLC-γ1, T cell adhesion and cytokine production. However, this model is largely based on studies of disruption of the GADS/SLP-76 interaction and murine T cell differentiation in GADS deficient mice. The role of GADS in mediating TCR-induced signals in human CD4+ T cells has not been thoroughly investigated. In this study, we have suppressed the expression of GADS in human CD4+ HuT78 T cells. GADS deficient HuT78 T cells displayed similar levels of TCR-induced SLP-76 and PLC-γ1 phosphorylation but exhibited substantial decrease in TCR-induced IL-2 and IFN-γ release. The defect in cytokine production occurred because of impaired calcium mobilization due to reduced recruitment of SLP-76 and PLC-γ1 to the LAT complex. Surprisingly, both GADS deficient HuT78 and GADS deficient primary murine CD8+ T cells had similar TCR-induced adhesion when compared to control T cells. Overall, our results show that GADS is required for calcium influx and cytokine production, but not cellular adhesion, in human CD4+ T cells, suggesting that the current model for T cell regulation by GADS is incomplete.
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Affiliation(s)
- Mahmood Y Bilal
- Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA 52242, United States
| | - Elizabeth Y Zhang
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, KS 66160, United States
| | - Brittney Dinkel
- Department of Microbiology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, United States
| | - Daimon Hardy
- Department of Microbiology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, United States
| | - Thomas M Yankee
- Department of Microbiology, Molecular Genetics and Immunology, University of Kansas Medical Center, Kansas City, KS 66160, United States
| | - Jon C D Houtman
- Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA 52242, United States; Department of Microbiology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, United States
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7
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Modulation of TCR responsiveness by the Grb2-family adaptor, Gads. Cell Signal 2014; 27:125-34. [PMID: 25452106 DOI: 10.1016/j.cellsig.2014.10.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Accepted: 10/16/2014] [Indexed: 12/11/2022]
Abstract
T cell antigen receptor (TCR) signaling depends on three interacting adaptor proteins: SLP-76, Gads, and LAT. Their mechanisms of signaling have been extensively explored, with the aid of fortuitously isolated LAT- and SLP-76-deficient T cell lines, but no such tools were available for Gads, a Grb2-family adaptor that bridges the TCR-inducible interaction between SLP-76 and LAT. TALEN-directed genome editing was applied to disrupt the first coding exon of human Gads in the Jurkat T cell line. Gads was dispensable for TCR-induced phosphorylation of SLP-76, but was a dose-dependent amplifier of TCR-induced CD69 expression. Gads conferred responsiveness to weak TCR stimuli, leading to PLC-γ1 phosphorylation and calcium flux. TALEN-derived, Gads-deficient T cell lines provide a uniquely tractable genetic platform for exploring its regulatory features, such as Gads phosphorylation at T262, which we observed by mass spectrometry. Upon mutation of this site, TCR responsiveness and sensitivity to weak TCR stimuli were increased. This study demonstrates the feasibility of TALEN-based reverse genetics in Jurkat T cells, while enriching our understanding of Gads as a regulated modulator of TCR sensitivity.
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8
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Sequential phosphorylation of SLP-76 at tyrosine 173 is required for activation of T and mast cells. EMBO J 2011; 30:3160-72. [PMID: 21725281 DOI: 10.1038/emboj.2011.213] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Accepted: 06/03/2011] [Indexed: 02/03/2023] Open
Abstract
Cooperatively assembled signalling complexes, nucleated by adaptor proteins, integrate information from surface receptors to determine cellular outcomes. In T and mast cells, antigen receptor signalling is nucleated by three adaptors: SLP-76, Gads and LAT. Three well-characterized SLP-76 tyrosine phosphorylation sites recruit key components, including a Tec-family tyrosine kinase, Itk. We identified a fourth, evolutionarily conserved SLP-76 phosphorylation site, Y173, which was phosphorylated upon T-cell receptor stimulation in primary murine and Jurkat T cells. Y173 was required for antigen receptor-induced phosphorylation of phospholipase C-γ1 (PLC-γ1) in both T and mast cells, and for consequent downstream events, including activation of the IL-2 promoter in T cells, and degranulation and IL-6 production in mast cells. In intact cells, Y173 phosphorylation depended on three, ZAP-70-targeted tyrosines at the N-terminus of SLP-76 that recruit and activate Itk, a kinase that selectively phosphorylated Y173 in vitro. These data suggest a sequential mechanism whereby ZAP-70-dependent priming of SLP-76 at three N-terminal sites triggers reciprocal regulatory interactions between Itk and SLP-76, which are ultimately required to couple active Itk to its substrate, PLC-γ1.
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9
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Cooperative interactions at the SLP-76 complex are critical for actin polymerization. EMBO J 2010; 29:2315-28. [PMID: 20562827 DOI: 10.1038/emboj.2010.133] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2009] [Accepted: 05/25/2010] [Indexed: 12/22/2022] Open
Abstract
T-cell antigen receptor (TCR) engagement induces formation of multi-protein signalling complexes essential for regulating T-cell functions. Generation of a complex of SLP-76, Nck and VAV1 is crucial for regulation of the actin machinery. We define the composition, stoichiometry and specificity of interactions in the SLP-76, Nck and VAV1 complex. Our data reveal that this complex can contain one SLP-76 molecule, two Nck and two VAV1 molecules. A direct interaction between Nck and VAV1 is mediated by binding between the C-terminal SH3 domain of Nck and the VAV1 N-terminal SH3 domain. Disruption of the VAV1:Nck interaction deleteriously affected actin polymerization. These novel findings shed new light on the mechanism of actin polymerization after T-cell activation.
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10
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Jung SH, Jeong JH, Seul HJ, Lee JR. Competition between SLP76 and LAT for PLCγ1 binding in resting T cells. Eur J Immunol 2010; 40:2330-9. [DOI: 10.1002/eji.200939411] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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11
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Abstract
In vitro data have suggested that activation of the inducible T-cell kinase (ITK) requires an interaction with the adaptor protein SLP-76. One means for this interaction involves binding of the ITK SH3 domain to the polyproline-rich (PR) region of SLP-76. However, the biological significance of this association in live cells and the consequences of its disruption have not been demonstrated. Here, we utilized a polyarginine-rich, cell-permeable peptide that represents the portion of the SLP-76 PR region that interacts with the ITK SH3 domain as a competitive inhibitor to disrupt the association between ITK and SLP-76 in live cells. We demonstrate that treatment of cells with this peptide, by either in vitro incubation or intraperitoneal injection of the peptide in mice, inhibits the T-cell receptor (TCR)-induced association between ITK and SLP-76, recruitment and transphosphorylation of ITK, actin polarization at the T-cell contact site, and expression of Th2 cytokines. The inhibition is specific, as indicated by lack of effects by the polyarginine vehicle alone or a scrambled sequence of the cargo peptide. In view of the role of ITK as a regulator of Th2 cytokine expression, the data underscore the significance of ITK as a target for pharmacological intervention.
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12
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Jordan MS, Koretzky GA. Coordination of receptor signaling in multiple hematopoietic cell lineages by the adaptor protein SLP-76. Cold Spring Harb Perspect Biol 2010; 2:a002501. [PMID: 20452948 DOI: 10.1101/cshperspect.a002501] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The adaptor protein SLP-76 is expressed in multiple hematopoietic lineages including T cells, platelets, and neutrophils. SLP-76 mediated signaling is dependent on its multiple protein interaction domains, as it creates a scaffold on which key signaling complexes are built. SLP-76 is critical for supporting signaling downstream of both immunoreceptors and integrins. The signaling molecules used both upstream and downstream of SLP-76 are similar among these receptors and across cell types; however, important differences exist. Appreciating how SLP-76 coordinates signal transduction across different cell and receptor types provides insights into the complex interplay of pathways critical for activation of cells of the immune system that are essential for host defense.
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Affiliation(s)
- Martha S Jordan
- Abramson Family Cancer Institute, University of Pennsylvania, Philadelphia, 19104, USA
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13
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Qi Q, August A. Keeping the (kinase) party going: SLP-76 and ITK dance to the beat. ACTA ACUST UNITED AC 2007; 2007:pe39. [PMID: 17652306 PMCID: PMC2756487 DOI: 10.1126/stke.3962007pe39] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The Tec-family protein tyrosine kinase IL-2-inducible T cell kinase (ITK) mediates T cell activation, as does the adaptor protein SLP-76 (SH2-domain-containing leukocyte protein of 76 kD), which forms a complex with ITK and other intracellular signaling enzymes. One of these enzymes is phospholipase C-gamma1 (PLC-gamma1), which mediates T cell receptor (TCR)-stimulated intracellular calcium mobilization leading to the activation of transcription factors such as nuclear factor of activated T cells. The Src-family tyrosine kinase Lck and the Syk-family tyrosine kinase zeta chain-associated protein kinase of 70 kD (ZAP-70), together with ITK, are necessary for the phosphorylation of PLC-gamma1 in response to TCR stimulation. ITK is thought to phosphorylate a specific tyrosine residue of PLC-gamma1 that is required for its activation. The mechanism of activation of ITK appears to involve the interaction between SLP-76 and ITK, which not only initiates ITK activity but is also important to maintain the kinase activity of ITK. This suggests that SLP-76 acts as more than a neutral adaptor in mediating T cell activation; SLP-76 also directly influences the kinase activity of ITK, allowing ITK to phosphorylate PLC-gamma1.
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Wu C, Ma MH, Brown KR, Geisler M, Li L, Tzeng E, Jia CYH, Jurisica I, Li SSC. Systematic identification of SH3 domain-mediated human protein–protein interactions by peptide array target screening. Proteomics 2007; 7:1775-85. [PMID: 17474147 DOI: 10.1002/pmic.200601006] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Systematic identification of direct protein-protein interactions is often hampered by difficulties in expressing and purifying the corresponding full-length proteins. By taking advantage of the modular nature of many regulatory proteins, we attempted to simplify protein-protein interactions to the corresponding domain-ligand recognition and employed peptide arrays to identify such binding events. A group of 12 Src homology (SH) 3 domains from eight human proteins (Swiss-Prot ID: SRC, PLCG1, P85A, NCK1, GRB2, FYN, CRK) were used to screen a peptide target array composed of 1536 potential ligands, which led to the identification of 921 binary interactions between these proteins and 284 targets. To assess the efficiency of the peptide array target screening (PATS) method in identifying authentic protein-protein interactions, we examined a set of interactions mediated by the PLCgamma1 SH3 domain by coimmunoprecipitation and/or affinity pull-downs using full-length proteins and achieved a 75% success rate. Furthermore, we characterized a novel interaction between PLCgamma1 and hematopoietic progenitor kinase 1 (HPK1) identified by PATS and demonstrated that the PLCgamma1 SH3 domain negatively regulated HPK1 kinase activity. Compared to protein interactions listed in the online predicted human interaction protein database (OPHID), the majority of interactions identified by PATS are novel, suggesting that, when extended to the large number of peptide interaction domains encoded by the human genome, PATS should aid in the mapping of the human interactome.
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Affiliation(s)
- Chenggang Wu
- Department of Biochemistry and the Siebens-Drake Research Institute, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
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Bogin Y, Ainey C, Beach D, Yablonski D. SLP-76 mediates and maintains activation of the Tec family kinase ITK via the T cell antigen receptor-induced association between SLP-76 and ITK. Proc Natl Acad Sci U S A 2007; 104:6638-43. [PMID: 17420479 PMCID: PMC1871838 DOI: 10.1073/pnas.0609771104] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
ITK (IL-2-inducible T cell kinase), a Tec family protein tyrosine kinase (PTK), is one of three PTKs required for T cell antigen receptor (TCR)-induced activation of phospholipase C-gamma1 (PLC-gamma1). Like Src and Abl family PTKs, ITK adopts an inactive, "closed" conformation, and its conversion to the active conformation is not well understood, nor have its direct substrates been identified. In a side-by-side comparison of ITK and ZAP-70 (zeta chain-associated protein kinase of 70 kDa), ITK efficiently phosphorylated Y(783) and Y(775) of PLC-gamma1, two phosphorylation sites that are critical for its activation, whereas ZAP-70 did not. SLP-76 (SH2-domain-containing leukocyte protein of 76 kDa), an adaptor required for TCR-induced activation of PLC-gamma1, was required for the phosphorylation of both PLC-gamma1 sites in intact cells. Furthermore, this event depended on the N-terminal tyrosines of SLP-76. Likewise, SLP-76, particularly its N-terminal tyrosines, was required for TCR-induced tyrosine phosphorylation and activation of ITK but was not required for the phosphorylation or activation of ZAP-70. Both ZAP-70 and ITK phosphorylated SLP-76 in vitro; thus, both PTKs are potential regulators of SLP-76, but only ITK is regulated by SLP-76. Upon TCR stimulation, a small fraction of ITK bound to SLP-76. This fraction, however, encompassed most of the catalytically active ITK. Catalytic activity was lost upon mild elution of ITK from the SLP-76-nucleated complex but was restored upon reconstitution of the complex. We propose that SLP-76 is required for ITK activation; furthermore, an ongoing physical interaction between SLP-76 and ITK is required to maintain ITK in an active conformation.
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Affiliation(s)
- Yaron Bogin
- The Rappaport Family Institute for Research in the Medical Sciences, The Bruce Rappaport Faculty of Medicine, Technion–Israel Institute of Technology, P.O. Box 9649, Bat Galim, Haifa 31096, Israel
| | - Carmit Ainey
- The Rappaport Family Institute for Research in the Medical Sciences, The Bruce Rappaport Faculty of Medicine, Technion–Israel Institute of Technology, P.O. Box 9649, Bat Galim, Haifa 31096, Israel
| | - Dvora Beach
- The Rappaport Family Institute for Research in the Medical Sciences, The Bruce Rappaport Faculty of Medicine, Technion–Israel Institute of Technology, P.O. Box 9649, Bat Galim, Haifa 31096, Israel
| | - Deborah Yablonski
- The Rappaport Family Institute for Research in the Medical Sciences, The Bruce Rappaport Faculty of Medicine, Technion–Israel Institute of Technology, P.O. Box 9649, Bat Galim, Haifa 31096, Israel
- *To whom correspondence should be addressed. E-mail:
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Beach D, Gonen R, Bogin Y, Reischl IG, Yablonski D. Dual role of SLP-76 in mediating T cell receptor-induced activation of phospholipase C-gamma1. J Biol Chem 2006; 282:2937-46. [PMID: 17148460 DOI: 10.1074/jbc.m606697200] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Phospholipase C-gamma1 (PLC-gamma1) activation depends on a heterotrimeric complex of adaptor proteins composed of LAT, Gads, and SLP-76. Upon T cell receptor stimulation, a portion of PLC-gamma1 is recruited to a detergent-resistant membrane fraction known as the glycosphingolipid-enriched membrane microdomains (GEMs), or lipid rafts, to which LAT is constitutively localized. In addition to LAT, PLC-gamma1 GEM recruitment depended on SLP-76, and, in particular, required the Gads-binding domain of SLP-76. The N-terminal tyrosine phosphorylation sites and P-I region of SLP-76 were not required for PLC-gamma1 GEM recruitment, but were required for PLC-gamma1 phosphorylation at Tyr(783). Thus, GEM recruitment can be insufficient for full activation of PLC-gamma1 in the absence of a second SLP-76-mediated event. Indeed, a GEM-targeted derivative of PLC-gamma1 depended on SLP-76 for T cell receptor-induced phosphorylation at Tyr783 and subsequent NFAT activation. On a biochemical level, SLP-76 inducibly associated with both Vav and catalytically active ITK, which efficiently phosphorylated a PLC-gamma1 fragment at Tyr783 in vitro. Both associations were disrupted upon mutation of the N-terminal tyrosine phosphorylation sites of SLP-76. The P-I region deletion disrupted Vav association and reduced SLP-76-associated kinase activity. A smaller deletion within the P-I region, which does not impair PLC-gamma1 activation, did not impair the association with Vav, but reduced SLP-76-associated kinase activity. These results provide new insight into the multiple roles of SLP-76 and the functional importance of its interactions with other signaling proteins.
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Affiliation(s)
- Dvora Beach
- Rappaport Family Institute for Research in the Medical Sciences, Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 31096, Israel
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Kliche S, Breitling D, Togni M, Pusch R, Heuer K, Wang X, Freund C, Kasirer-Friede A, Menasche G, Koretzky GA, Schraven B. The ADAP/SKAP55 signaling module regulates T-cell receptor-mediated integrin activation through plasma membrane targeting of Rap1. Mol Cell Biol 2006; 26:7130-44. [PMID: 16980616 PMCID: PMC1592884 DOI: 10.1128/mcb.00331-06] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Adhesion of T cells after stimulation of the T-cell receptor (TCR) is mediated via signaling processes that have collectively been termed inside-out signaling. The molecular basis for inside-out signaling is not yet completely understood. Here, we show that a signaling module comprising the cytosolic adapter proteins ADAP and SKAP55 is involved in TCR-mediated inside-out signaling and, moreover, that the interaction between ADAP and SKAP55 is mandatory for integrin activation. Disruption of the ADAP/SKAP55 module leads to displacement of the small GTPase Rap1 from the plasma membrane without influencing its GTPase activity. These findings suggest that the ADAP/SKAP55 complex serves to recruit activated Rap1 to the plasma membrane. In line with this hypothesis is the finding that membrane targeting of the ADAP/SKAP55 module induces T-cell adhesion in the absence of TCR-mediated stimuli. However, it appears as if the ADAP/SKAP55 module can exert its signaling function outside of the classical raft fraction of the cell membrane.
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Affiliation(s)
- Stefanie Kliche
- Institute of Immunology, Otto von Guericke University, 39120 Magdeburg, Germany.
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Koretzky GA, Abtahian F, Silverman MA. SLP76 and SLP65: complex regulation of signalling in lymphocytes and beyond. Nat Rev Immunol 2006; 6:67-78. [PMID: 16493428 DOI: 10.1038/nri1750] [Citation(s) in RCA: 205] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
SLP76 and SLP65 are adaptor proteins that lack intrinsic enzymatic activity but contain multiple protein-binding domains. These proteins are essential for signalling downstream of integrins and receptors that contain immunoreceptor tyrosine-based activation motifs. The absence of these adaptor proteins profoundly affects various lineages in the haematopoietic compartment and severely compromises vascular development, highlighting their importance as regulators of signalling cascades. In this Review, we discuss the role of SLP76 and SLP65 in several signalling pathways in haematopoietic cells, with an emphasis on recent studies that provide insight into their mechanisms of action.
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Affiliation(s)
- Gary A Koretzky
- Department of Pathology and Laboratory Medicine, Abramson Family Cancer Research Institute, University of Pennsylvania, 415 BRBII/III, 421 Curie Boulevard, Philadelphia, Pennsylvania 19104, USA.
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Braiman A, Barda-Saad M, Sommers CL, Samelson LE. Recruitment and activation of PLCgamma1 in T cells: a new insight into old domains. EMBO J 2006; 25:774-84. [PMID: 16467851 PMCID: PMC1383559 DOI: 10.1038/sj.emboj.7600978] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2005] [Accepted: 01/09/2006] [Indexed: 11/09/2022] Open
Abstract
Engagement of the T-cell antigen receptor leads to recruitment of phospholipase Cgamma1 (PLCgamma1) to the LAT-nucleated signaling complex and to PLCgamma1 activation in a tyrosine phosphorylation-dependent manner. The mechanism of PLCgamma1 recruitment and the role of PLCgamma1 Src homology (SH) domains in this process remain incompletely understood. Using a combination of biochemical methods and real-time fluorescent imaging, we show here that the N-terminal SH2 domain of PLCgamma1 is necessary but not sufficient for its recruitment. Either the SH3 or C-terminal SH2 domain of PLCgamma1, with the participation of Vav1, c-Cbl and Slp76, are required to stabilize PLCgamma1 recruitment. All three PLCgamma1 SH domains are required for phosphorylation of PLCgamma1 Y783, which is critical for enzyme activation. These novel findings entailed revision of the currently accepted model of PLCgamma1 recruitment and activation in T lymphocytes.
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Affiliation(s)
- Alex Braiman
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Mira Barda-Saad
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Connie L Sommers
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Lawrence E Samelson
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Building 37, Room 2066, Bethesda, MD 20892-4254, USA. Tel.: +1 301 496 9683; Fax: +1 301 496 8479; E-mail:
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Kumar L, Feske S, Rao A, Geha RS. A 10-aa-long sequence in SLP-76 upstream of the Gads binding site is essential for T cell development and function. Proc Natl Acad Sci U S A 2005; 102:19063-8. [PMID: 16354835 PMCID: PMC1323183 DOI: 10.1073/pnas.0509176102] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The adapter SLP-76 is essential for T cell development and function. SLP-76 binds to the src homology 3 domain of Lck in vitro. This interaction depends on amino acids 185-194 of SLP-76. To examine the role of the Lck-binding region of SLP-76 in T cell development and function, SLP-76(-/-) mice were reconstituted with an SLP-76 mutant that lacks amino acids 185-194. Double and single positive thymocytes from reconstituted mice were severely reduced in numbers and exhibited impaired positive selection and increased apoptosis. Peripheral T cells were also reduced in numbers, exhibited impaired phospholipase C-gamma1 and Erk phosphorylation, and failed to flux calcium, secrete IL-2, and proliferate in response to T cell antigen receptor ligation. Delayed cutaneous hypersensitivity responses and Ab responses to T cell-dependent antigen were severely impaired. These results indicate that the Lck binding region of SLP-76 is essential for T cell antigen receptor signaling and normal T cell development and function.
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Affiliation(s)
- Lalit Kumar
- Division of Immunology, Children's Hospital, CBR Institute for Biomedical Research, Harvard Medical School, Boston, MA 02115, USA
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Abstract
Dynamic protein-protein interactions are involved in most physiological processes and, in particular, for the formation of multiprotein signaling complexes at transmembrane receptors, adapter proteins and effector molecules. Because the unregulated induction of signaling complexes has substantial clinical relevance, the investigation of these complexes is an active area of research. These studies strive to answer questions about the composition and function of multiprotein signaling complexes, along with the molecular mechanisms of their formation. In this review, the adapter protein, linker for activation of T cells (LAT), will be employed as a model to exemplify how signaling complexes are characterized using a range of techniques. The intensive investigation of LAT highlights how the systematic use of complementary techniques leads to an integrated understanding of the formation, composition and function of multiprotein signaling complexes that occur at receptors, adapter proteins and effector molecules.
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Affiliation(s)
- Jon C D Houtman
- Laboratory of Cellular and Molecular Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
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