1
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Sec61 channel subunit Sbh1/Sec61β promotes ER translocation of proteins with suboptimal targeting sequences and is fine-tuned by phosphorylation. J Biol Chem 2023; 299:102895. [PMID: 36639027 PMCID: PMC9947333 DOI: 10.1016/j.jbc.2023.102895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 12/07/2022] [Accepted: 12/09/2022] [Indexed: 01/12/2023] Open
Abstract
The highly conserved endoplasmic reticulum (ER) protein translocation channel contains one nonessential subunit, Sec61β/Sbh1, whose function is poorly understood so far. Its intrinsically unstructured cytosolic domain makes transient contact with ER-targeting sequences in the cytosolic channel vestibule and contains multiple phosphorylation sites suggesting a potential for regulating ER protein import. In a microscopic screen, we show that 12% of a GFP-tagged secretory protein library depends on Sbh1 for translocation into the ER. Sbh1-dependent proteins had targeting sequences with less pronounced hydrophobicity and often no charge bias or an inverse charge bias which reduces their insertion efficiency into the Sec61 channel. We determined that mutating two N-terminal, proline-flanked phosphorylation sites in the Sbh1 cytosolic domain to alanine phenocopied the temperature-sensitivity of a yeast strain lacking SBH1 and its ortholog SBH2. The phosphorylation site mutations reduced translocation into the ER of a subset of Sbh1-dependent proteins, including enzymes whose concentration in the ER lumen is critical for ER proteostasis. In addition, we found that ER import of these proteins depended on the activity of the phospho-S/T-specific proline isomerase Ess1 (PIN1 in mammals). We conclude that Sbh1 promotes ER translocation of substrates with suboptimal targeting sequences and that its activity can be regulated by a conformational change induced by N-terminal phosphorylation.
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2
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Zhou L, Wang T, Zhang K, Zhang X, Jiang S. The development of small-molecule inhibitors targeting HPK1. Eur J Med Chem 2022; 244:114819. [DOI: 10.1016/j.ejmech.2022.114819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 09/29/2022] [Accepted: 09/30/2022] [Indexed: 11/25/2022]
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3
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Zhu Q, Chen N, Tian X, Zhou Y, You Q, Xu X. Hematopoietic Progenitor Kinase 1 in Tumor Immunology: A Medicinal Chemistry Perspective. J Med Chem 2022; 65:8065-8090. [PMID: 35696642 DOI: 10.1021/acs.jmedchem.2c00172] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Hematopoietic progenitor kinase 1 (HPK1), a hematopoietic cell-restricted member of the serine/threonine Ste20-related protein kinases, is a negative regulator of the T cell receptor, B cell receptor, and dendritic cells. Loss of HPK1 kinase function increases cytokine secretion and enhances T cell signaling, virus clearance, and tumor growth inhibition. Therefore, HPK1 is considered a promising target for tumor immunotherapy. Several HPK1 inhibitors have been reported to regulate T cell function. In addition, HPK1-targeting PROTACs, which can induce the degradation of HPK1, have also been developed. Here, we provide an overview of research concerning HPK1 protein structure, function, and inhibitors and propose perspectives and insights for the future development of agents targeting HPK1.
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Affiliation(s)
- Qiangsheng Zhu
- State Key Laboratory of Natural Medicines and Jiang Su Key Laboratory of Drug Design and Optimization, Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - Nannan Chen
- State Key Laboratory of Natural Medicines and Jiang Su Key Laboratory of Drug Design and Optimization, Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - Xinjian Tian
- State Key Laboratory of Natural Medicines and Jiang Su Key Laboratory of Drug Design and Optimization, Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - Yeling Zhou
- State Key Laboratory of Natural Medicines and Jiang Su Key Laboratory of Drug Design and Optimization, Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - QiDong You
- State Key Laboratory of Natural Medicines and Jiang Su Key Laboratory of Drug Design and Optimization, Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - Xiaoli Xu
- State Key Laboratory of Natural Medicines and Jiang Su Key Laboratory of Drug Design and Optimization, Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
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4
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Bader A, Winkelmann M, Forné I, Walzog B, Maier-Begandt D. Decoding the signaling profile of hematopoietic progenitor kinase 1 (HPK1) in innate immunity: a proteomic approach. Eur J Immunol 2022; 52:760-769. [PMID: 35099066 DOI: 10.1002/eji.202149283] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 12/06/2021] [Accepted: 01/14/2022] [Indexed: 11/10/2022]
Abstract
Signaling via β2 integrins (CD11/CD18) as well as T and B cell receptors involves similar pathways. However, the activation of the same signaling molecule can result in opposing effects. One such example is the hematopoietic progenitor kinase 1 (HPK1), which negatively regulates T and B cell activation but enforces neutrophil adhesion via β2 integrins. This difference may be defined by specific HPK1 interacting networks in different leukocyte subsets which have already been described in the adaptive immune system. Here, we set out to identify interacting proteins of HPK1 in neutrophil-like differentiated HL-60 cells exposed to immobilized fibrinogen and left non-activated or Mn2+ -activated to allow β2 integrin-dependent adhesion. Co-immunoprecipitation experiments followed by mass spectrometry led to the identification of 115 HPK1-interacting proteins. 58 proteins were found only in non-activated cells and 39 proteins only in Mn2+ -activated adherent cells. From these results we decoded a pre-existing signaling cluster of HPK1 in non-activated cells encompassing proteins essential for β2 integrin-mediated signaling during neutrophil trafficking, namely DNAX-activation protein 12 (DAP12), spleen tyrosine kinase (Syk) and Rac1. Thus, our study provides novel insights into the complex architecture of the signaling processes during neutrophil activation and the complex signaling profile of HPK1 in leukocytes. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Almke Bader
- Institute of Cardiovascular Physiology and Pathophysiology, Biomedical Center, LMU Munich, Planegg-Martinsried, 82152, Germany.,Walter Brendel Center of Experimental Medicine, University Hospital, LMU Munich, Munich, 81377, Germany
| | - Michael Winkelmann
- Institute of Cardiovascular Physiology and Pathophysiology, Biomedical Center, LMU Munich, Planegg-Martinsried, 82152, Germany.,Walter Brendel Center of Experimental Medicine, University Hospital, LMU Munich, Munich, 81377, Germany.,Department of Radiology, University Hospital, LMU Munich, Munich, 81377, Germany
| | - Ignasi Forné
- Protein Analysis Unit, Biomedical Center, LMU Munich, Planegg-Martinsried, 82152, Germany
| | - Barbara Walzog
- Institute of Cardiovascular Physiology and Pathophysiology, Biomedical Center, LMU Munich, Planegg-Martinsried, 82152, Germany.,Walter Brendel Center of Experimental Medicine, University Hospital, LMU Munich, Munich, 81377, Germany
| | - Daniela Maier-Begandt
- Institute of Cardiovascular Physiology and Pathophysiology, Biomedical Center, LMU Munich, Planegg-Martinsried, 82152, Germany.,Walter Brendel Center of Experimental Medicine, University Hospital, LMU Munich, Munich, 81377, Germany
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5
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Vincenzi M, Mercurio FA, Leone M. Protein Interaction Domains: Structural Features and Drug Discovery Applications (Part 2). Curr Med Chem 2021; 28:854-892. [PMID: 31942846 DOI: 10.2174/0929867327666200114114142] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 10/28/2019] [Accepted: 11/04/2019] [Indexed: 11/22/2022]
Abstract
BACKGROUND Proteins present a modular organization made up of several domains. Apart from the domains playing catalytic functions, many others are crucial to recruit interactors. The latter domains can be defined as "PIDs" (Protein Interaction Domains) and are responsible for pivotal outcomes in signal transduction and a certain array of normal physiological and disease-related pathways. Targeting such PIDs with small molecules and peptides able to modulate their interaction networks, may represent a valuable route to discover novel therapeutics. OBJECTIVE This work represents a continuation of a very recent review describing PIDs able to recognize post-translationally modified peptide segments. On the contrary, the second part concerns with PIDs that interact with simple peptide sequences provided with standard amino acids. METHODS Crucial structural information on different domain subfamilies and their interactomes was gained by a wide search in different online available databases (including the PDB (Protein Data Bank), the Pfam (Protein family), and the SMART (Simple Modular Architecture Research Tool)). Pubmed was also searched to explore the most recent literature related to the topic. RESULTS AND CONCLUSION PIDs are multifaceted: they have all diverse structural features and can recognize several consensus sequences. PIDs can be linked to different diseases onset and progression, like cancer or viral infections and find applications in the personalized medicine field. Many efforts have been centered on peptide/peptidomimetic inhibitors of PIDs mediated interactions but much more work needs to be conducted to improve drug-likeness and interaction affinities of identified compounds.
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Affiliation(s)
- Marian Vincenzi
- Institute of Biostructures and Bioimaging, National Research Council (CNR), Via Mezzocannone 16, 80134 Naples, Italy
| | - Flavia Anna Mercurio
- Institute of Biostructures and Bioimaging, National Research Council (CNR), Via Mezzocannone 16, 80134 Naples, Italy
| | - Marilisa Leone
- Institute of Biostructures and Bioimaging, National Research Council (CNR), Via Mezzocannone 16, 80134 Naples, Italy
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6
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Yablonski D. Bridging the Gap: Modulatory Roles of the Grb2-Family Adaptor, Gads, in Cellular and Allergic Immune Responses. Front Immunol 2019; 10:1704. [PMID: 31402911 PMCID: PMC6669380 DOI: 10.3389/fimmu.2019.01704] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 07/08/2019] [Indexed: 01/07/2023] Open
Abstract
Antigen receptor signaling pathways are organized by adaptor proteins. Three adaptors, LAT, Gads, and SLP-76, form a heterotrimeric complex that mediates signaling by the T cell antigen receptor (TCR) and by the mast cell high affinity receptor for IgE (FcεRI). In both pathways, antigen recognition triggers tyrosine phosphorylation of LAT and SLP-76. The recruitment of SLP-76 to phospho-LAT is bridged by Gads, a Grb2 family adaptor composed of two SH3 domains flanking a central SH2 domain and an unstructured linker region. The LAT-Gads-SLP-76 complex is further incorporated into larger microclusters that mediate antigen receptor signaling. Gads is positively regulated by dimerization, which promotes its cooperative binding to LAT. Negative regulation occurs via phosphorylation or caspase-mediated cleavage of the linker region of Gads. FcεRI-mediated mast cell activation is profoundly impaired in LAT- Gads- or SLP-76-deficient mice. Unexpectedly, the thymic developmental phenotype of Gads-deficient mice is much milder than the phenotype of LAT- or SLP-76-deficient mice. This distinction suggests that Gads is not absolutely required for TCR signaling, but may modulate its sensitivity, or regulate a particular branch of the TCR signaling pathway; indeed, the phenotypic similarity of Gads- and Itk-deficient mice suggests a functional connection between Gads and Itk. Additional Gads binding partners include costimulatory proteins such as CD28 and CD6, adaptors such as Shc, ubiquitin regulatory proteins such as USP8 and AMSH, and kinases such as HPK1 and BCR-ABL, but the functional implications of these interactions are not yet fully understood. No interacting proteins or function have been ascribed to the evolutionarily conserved N-terminal SH3 of Gads. Here we explore the biochemical and functional properties of Gads, and its role in regulating allergy, T cell development and T-cell mediated immunity.
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Affiliation(s)
- Deborah Yablonski
- The Immune Cell Signaling Lab, Department of Immunology, Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel
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7
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Niveshika, Maurya SK, Tiwari B, Chakraborty S, Verma E, Mishra R, Mishra AK. Cyanobacterial bioactive compound EMTAHDCA recovers splenomegaly, affects protein profile of E. coli and spleen of lymphoma bearing mice. Mol Biol Rep 2019; 46:2617-2629. [DOI: 10.1007/s11033-019-04659-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Accepted: 01/28/2019] [Indexed: 12/11/2022]
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8
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Liu J, Curtin J, You D, Hillerman S, Li-Wang B, Eraslan R, Xie J, Swanson J, Ho CP, Oppenheimer S, Warrack BM, McNaney CA, Nelson DM, Blum J, Kim T, Fereshteh M, Reily M, Shipkova P, Murtaza A, Sanjuan M, Hunt JT, Salter-Cid L. Critical role of kinase activity of hematopoietic progenitor kinase 1 in anti-tumor immune surveillance. PLoS One 2019; 14:e0212670. [PMID: 30913212 PMCID: PMC6435129 DOI: 10.1371/journal.pone.0212670] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 02/07/2019] [Indexed: 01/05/2023] Open
Abstract
Immunotherapy has fundamentally changed the landscape of cancer treatment. Despite the encouraging results with the checkpoint modulators, response rates vary widely across tumor types, with a majority of patients exhibiting either primary resistance without a significant initial response to treatment or acquired resistance with subsequent disease progression. Hematopoietic progenitor kinase 1 (HPK1) is predominantly expressed in hematopoietic cell linages and serves as a negative regulator in T cells and dendritic cells (DC). While HPK1 gene knockout (KO) studies suggest its role in anti-tumor immune responses, the involvement of kinase activity and thereof its therapeutic potential remain unknown. To investigate the potential of pharmacological intervention using inhibitors of HPK1, we generated HPK1 kinase dead (KD) mice which carry a single loss-of-function point mutation in the kinase domain and interrogated the role of kinase activity in immune cells in the context of suppressive factors or the tumor microenvironment (TME). Our data provide novel findings that HKP1 kinase activity is critical in conferring suppressive functions of HPK1 in a wide range of immune cells including CD4+, CD8+, DC, NK to Tregs, and inactivation of kinase domain was sufficient to elicit robust anti-tumor immune responses. These data support the concept that an HPK1 small molecule kinase inhibitor could serve as a novel agent to provide additional benefit in combination with existing immunotherapies, particularly to overcome resistance to current treatment regimens.
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Affiliation(s)
- Jinqi Liu
- Immuno-oncology Discovery, Bristol Myers Squibb, Princeton, New Jersey, United States of America
| | - Joshua Curtin
- Immuno-oncology Discovery, Bristol Myers Squibb, Princeton, New Jersey, United States of America
| | - Dan You
- Immuno-oncology Discovery, Bristol Myers Squibb, Princeton, New Jersey, United States of America
| | - Stephen Hillerman
- Immuno-oncology Discovery, Bristol Myers Squibb, Princeton, New Jersey, United States of America
| | - Bifang Li-Wang
- Immuno-oncology Discovery, Bristol Myers Squibb, Princeton, New Jersey, United States of America
| | - Rukiye Eraslan
- Immuno-oncology Discovery, Bristol Myers Squibb, Princeton, New Jersey, United States of America
| | - Jenny Xie
- Immuno-oncology Discovery, Bristol Myers Squibb, Princeton, New Jersey, United States of America
| | - Jesse Swanson
- Immuno-oncology Discovery, Bristol Myers Squibb, Princeton, New Jersey, United States of America
| | - Ching-Ping Ho
- Immuno-oncology Discovery, Bristol Myers Squibb, Princeton, New Jersey, United States of America
| | - Simone Oppenheimer
- Immuno-oncology Discovery, Bristol Myers Squibb, Princeton, New Jersey, United States of America
| | - Bethanne M. Warrack
- Immuno-oncology Discovery, Bristol Myers Squibb, Princeton, New Jersey, United States of America
| | - Colleen A. McNaney
- Immuno-oncology Discovery, Bristol Myers Squibb, Princeton, New Jersey, United States of America
| | - David M. Nelson
- Immuno-oncology Discovery, Bristol Myers Squibb, Princeton, New Jersey, United States of America
| | - Jordan Blum
- Immuno-oncology Discovery, Bristol Myers Squibb, Princeton, New Jersey, United States of America
| | - Taeg Kim
- Immuno-oncology Discovery, Bristol Myers Squibb, Princeton, New Jersey, United States of America
| | - Mark Fereshteh
- Immuno-oncology Discovery, Bristol Myers Squibb, Princeton, New Jersey, United States of America
| | - Michael Reily
- Immuno-oncology Discovery, Bristol Myers Squibb, Princeton, New Jersey, United States of America
| | - Petia Shipkova
- Immuno-oncology Discovery, Bristol Myers Squibb, Princeton, New Jersey, United States of America
| | - Anwar Murtaza
- Immuno-oncology Discovery, Bristol Myers Squibb, Princeton, New Jersey, United States of America
| | - Miguel Sanjuan
- Immuno-oncology Discovery, Bristol Myers Squibb, Princeton, New Jersey, United States of America
| | - John T. Hunt
- Immuno-oncology Discovery, Bristol Myers Squibb, Princeton, New Jersey, United States of America
| | - Luisa Salter-Cid
- Immuno-oncology Discovery, Bristol Myers Squibb, Princeton, New Jersey, United States of America
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9
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Yablonski D. Bridging the Gap: Modulatory Roles of the Grb2-Family Adaptor, Gads, in Cellular and Allergic Immune Responses. Front Immunol 2019; 10:1704. [PMID: 31402911 DOI: 10.3389/fimmu.2019.01704/full] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 07/08/2019] [Indexed: 05/22/2023] Open
Abstract
Antigen receptor signaling pathways are organized by adaptor proteins. Three adaptors, LAT, Gads, and SLP-76, form a heterotrimeric complex that mediates signaling by the T cell antigen receptor (TCR) and by the mast cell high affinity receptor for IgE (FcεRI). In both pathways, antigen recognition triggers tyrosine phosphorylation of LAT and SLP-76. The recruitment of SLP-76 to phospho-LAT is bridged by Gads, a Grb2 family adaptor composed of two SH3 domains flanking a central SH2 domain and an unstructured linker region. The LAT-Gads-SLP-76 complex is further incorporated into larger microclusters that mediate antigen receptor signaling. Gads is positively regulated by dimerization, which promotes its cooperative binding to LAT. Negative regulation occurs via phosphorylation or caspase-mediated cleavage of the linker region of Gads. FcεRI-mediated mast cell activation is profoundly impaired in LAT- Gads- or SLP-76-deficient mice. Unexpectedly, the thymic developmental phenotype of Gads-deficient mice is much milder than the phenotype of LAT- or SLP-76-deficient mice. This distinction suggests that Gads is not absolutely required for TCR signaling, but may modulate its sensitivity, or regulate a particular branch of the TCR signaling pathway; indeed, the phenotypic similarity of Gads- and Itk-deficient mice suggests a functional connection between Gads and Itk. Additional Gads binding partners include costimulatory proteins such as CD28 and CD6, adaptors such as Shc, ubiquitin regulatory proteins such as USP8 and AMSH, and kinases such as HPK1 and BCR-ABL, but the functional implications of these interactions are not yet fully understood. No interacting proteins or function have been ascribed to the evolutionarily conserved N-terminal SH3 of Gads. Here we explore the biochemical and functional properties of Gads, and its role in regulating allergy, T cell development and T-cell mediated immunity.
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Affiliation(s)
- Deborah Yablonski
- The Immune Cell Signaling Lab, Department of Immunology, Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel
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10
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Wu P, Sneeringer CJ, Pitts KE, Day ES, Chan BK, Wei B, Lehoux I, Mortara K, Li H, Wu J, Franke Y, Moffat JG, Grogan JL, Heffron TP, Wang W. Hematopoietic Progenitor Kinase-1 Structure in a Domain-Swapped Dimer. Structure 2018; 27:125-133.e4. [PMID: 30503777 DOI: 10.1016/j.str.2018.10.025] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Revised: 07/27/2018] [Accepted: 10/25/2018] [Indexed: 12/12/2022]
Abstract
Enhancement of antigen-specific T cell immunity has shown significant therapeutic benefit in infectious diseases and cancer. Hematopoietic progenitor kinase-1 (HPK1) is a negative-feedback regulator of T cell receptor signaling, which dampens T cell proliferation and effector function. A recent report showed that a catalytic dead mutant of HPK1 phenocopies augmented T cell responses observed in HPK1-knockout mice, indicating that kinase activity is critical for function. We evaluated active and inactive mutants and determined crystal structures of HPK1 kinase domain (HPK1-KD) in apo and ligand bound forms. In all structures HPK1-KD displays a rare domain-swapped dimer, in which the activation segment comprises a well-conserved dimer interface. Biophysical measurements show formation of dimer in solution. The activation segment adopts an α-helical structure which exhibits distinct orientations in active and inactive states. This face-to-face configuration suggests that the domain-swapped dimer may possess alternative selectivity for certain substrates of HPK1 under relevant cellular context.
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Affiliation(s)
- Ping Wu
- Department of Structural Biology, Genentech, South San Francisco, CA 94080, USA
| | | | - Keith E Pitts
- Department of Biochemical Pharmacology, Genentech, South San Francisco, CA 94080, USA
| | - Eric S Day
- Department of Late Stage Pharmaceutical Development, Genentech, South San Francisco, CA 94080, USA
| | - Bryan K Chan
- Department of Discovery Chemistry, Genentech, South San Francisco, CA 94080, USA
| | - Binqing Wei
- Department of Discovery Chemistry, Genentech, South San Francisco, CA 94080, USA
| | - Isabelle Lehoux
- Department of Biomolecular Resources, Genentech, South San Francisco, CA 94080, USA
| | - Kyle Mortara
- Department of Biomolecular Resources, Genentech, South San Francisco, CA 94080, USA
| | - Hong Li
- Department of Protein Chemistry, Genentech, South San Francisco, CA 94080, USA
| | - Jiansheng Wu
- Department of Protein Chemistry, Genentech, South San Francisco, CA 94080, USA
| | - Yvonne Franke
- Department of Biomolecular Resources, Genentech, South San Francisco, CA 94080, USA
| | - John G Moffat
- Department of Biochemical Pharmacology, Genentech, South San Francisco, CA 94080, USA
| | - Jane L Grogan
- Department of Cancer Immunology, Genentech, South San Francisco, CA 94080, USA
| | - Timothy P Heffron
- Department of Discovery Chemistry, Genentech, South San Francisco, CA 94080, USA
| | - Weiru Wang
- Department of Structural Biology, Genentech, South San Francisco, CA 94080, USA.
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11
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Dunkelberger JR, Serão NVL, Weng Z, Waide EH, Niederwerder MC, Kerrigan MA, Lunney JK, Rowland RRR, Dekkers JCM. Genomic regions associated with host response to porcine reproductive and respiratory syndrome vaccination and co-infection in nursery pigs. BMC Genomics 2017; 18:865. [PMID: 29132293 PMCID: PMC5682865 DOI: 10.1186/s12864-017-4182-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 10/05/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The WUR1000125 (WUR) single nucleotide polymorphism (SNP) can be used as a genetic marker for host response to porcine reproductive and respiratory syndrome (PRRS), PRRS vaccination, and co-infection with porcine circovirus type 2b (PCV2b). Objectives of this study were to identify genomic regions other than WUR associated with host response to PRRS vaccination and PRRSV/PCV2b co-infection and regions with a different effect on host response to co-infection, depending on previous vaccination for PRRS. METHODS Commercial crossbred nursery pigs were pre-selected for WUR genotype (n = 171 AA and 198 AB pigs) where B is the dominant and favorable allele. Half of the pigs were vaccinated for PRRS and 4 weeks later, all pigs were co-infected with PRRS virus and PCV2b. Average daily gain (ADG) and viral load (VL) were quantified post vaccination (Post Vx) and post co-infection (Post Co-X). Single-SNP genome-wide association analyses were then conducted to identify genomic regions associated with response to vaccination and co-infection. RESULTS Multiple SNPs near the major histocompatibility complex were significantly associated with PCV2b VL (-log 10 P ≥ 5.5), regardless of prior vaccination for PRRS. Several SNPs were also significantly associated with ADG Post Vx and Post Co-X. SNPs with a different effect on ADG, depending on prior vaccination for PRRS, were identified Post Vx (-log 10 P = 5.6) and Post Co-X (-log 10 P = 5.5). No SNPs were significantly associated with vaccination VL (-log10 P ≤ 4.7) or PRRS VL (-log10 P ≤ 4.3). Genes near SNPs associated with vaccination VL, PRRS VL, and PCV2b VL were enriched (P ≤ 0.01) for immune-related pathways and genes near SNPs associated with ADG were enriched for metabolism pathways (P ≤ 0.04). SNPs associated with vaccination VL, PRRS VL, and PCV2b VL showed overrepresentation of health QTL identified in previous studies and SNPs associated with ADG Post Vx of Non-Vx pigs showed overrepresentation of growth QTL. CONCLUSIONS Multiple genomic regions were associated with PCV2b VL and ADG Post Vx and Post Co-X. Different SNPs were associated with ADG, depending on previous vaccination for PRRS. Results of functional annotation analyses and novel approaches of using previously-reported QTL support the identified regions.
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Affiliation(s)
- Jenelle R Dunkelberger
- Department of Animal Science, Iowa State University, Ames, IA, 50011, USA.,Topigs Norsvin USA, Burnsville, MN, 55337, USA
| | - Nick V L Serão
- Department of Animal Science, Iowa State University, Ames, IA, 50011, USA
| | - Ziqing Weng
- Department of Animal Science, Iowa State University, Ames, IA, 50011, USA.,ABS Global Inc., DeForest, WI, 53532, USA
| | - Emily H Waide
- Department of Animal Science, Iowa State University, Ames, IA, 50011, USA.,The Seeing Eye Inc., Morristown, NJ, 07960, USA
| | - Megan C Niederwerder
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, 66506, USA
| | - Maureen A Kerrigan
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, 66506, USA
| | | | - Raymond R R Rowland
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, 66506, USA
| | - Jack C M Dekkers
- Department of Animal Science, Iowa State University, Ames, IA, 50011, USA.
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12
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Zhang Q, Ding S, Zhang H. Interactions between hematopoietic progenitor kinase 1 and its adaptor proteins. Mol Med Rep 2017; 16:6472-6482. [DOI: 10.3892/mmr.2017.7494] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Accepted: 07/31/2017] [Indexed: 11/06/2022] Open
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13
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14
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Wang H, Chen Y, Lin P, Li L, Zhou G, Liu G, Logsdon C, Jin J, Abbruzzese JL, Tan TH, Wang H. The CUL7/F-box and WD repeat domain containing 8 (CUL7/Fbxw8) ubiquitin ligase promotes degradation of hematopoietic progenitor kinase 1. J Biol Chem 2013; 289:4009-17. [PMID: 24362026 DOI: 10.1074/jbc.m113.520106] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
HPK1, a member of mammalian Ste20-like serine/threonine kinases, is lost in >95% pancreatic cancer through proteasome-mediated degradation. However, the mechanism of HPK1 loss has not been defined. The aims of this study are to identify the ubiquitin ligase and to examine the mechanisms that targets HPK1 degradation. We found that the CUL7/Fbxw8 ubiquitin ligase targeted HPK1 for degradation via the 26 S proteasome. The ubiquitination of HPK1 required its kinase activity and autophosphorylation. Wild-type protein phosphatase 4 (PP4), but not the phosphatase-dead PP4 mutant, PP4-RL, inhibits the interaction of Fbxw8 with HPK1 and Fbxw8-mediated ubiquitination of HPK1. In addition, we showed that Thr-355 of HPK1 is a key PP4 dephosphorylation site, through which CUL7/Fbxw8 ubiquitin ligase and PP4 regulates HPK1 stability. Knockdown of Fbxw8 restores endogenous HPK1 protein expression and inhibits cell proliferation of pancreatic cancer cells. Our study demonstrated that targeted degradation of HPK1 by the CUL7/Fbxw8 ubiquitin ligase constitutes a negative-feedback loop to restrain the activity of HPK1 and that CUL7/Fbxw8 ubiquitin ligase promotes pancreatic cancer cell proliferation. CUL7/Fbxw8 ubiquitin ligase-mediated HPK1 degradation revealed a direct link and novel role of CUL7/Fbxw8 ubiquitin ligase in the MAPK pathway, which plays a critical role in cell proliferation and differentiation.
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Affiliation(s)
- Hua Wang
- From the Departments of Gastrointestinal Medical Oncology
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15
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Chen-Deutsch X, Studzinski GP. Dual role of hematopoietic progenitor kinase 1 (HPK1) as a positive regulator of 1α,25-dihydroxyvitamin D-induced differentiation and cell cycle arrest of AML cells and as a mediator of vitamin D resistance. Cell Cycle 2012; 11:1364-73. [PMID: 22421156 DOI: 10.4161/cc.19765] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Recent clinical trials aimed at improved treatment of AML by administration of vitamin D derivatives showed unremarkable results, suggesting development of vitamin D resistance in patients' AML blasts. Since mechanisms of vitamin D resistance are not clear, we studied 40AF cells, a subline of HL60 cells that can proliferate in the presence of 1α,25-dihydroxyvitamin D₃ (1,25D). We found that mRNA and protein levels of HPK1, an upstream MAP4 kinase, are dramatically increased in 40AF cells, and HPK1 protein is further increased when the 1,25D resistance of 40AF cells is partially reversed by the addition of carnosic acid and p38MAPK inhibitor SB202190 (DCS cocktail). Knockdown of HPK1 reduces 1,25D/DCS-induced differentiation of both 1,25D-sensitive HL60 and U937 cells and 1,25D-resistant 40AF cells, but the effect of HPK1 knockdown on differentiation-associated G 1 arrest is more apparent in the resistant than the sensitive cells. To explain why 40AF and the intrinsically vitamin D-resistant KG-1a cells can proliferate in the presence of vitamin D, we found that the cleaved HPK1 fragment (HPK1-C) level is high in 40AF and KG-1a cells, but when differentiation is induced by DCS, HPK1-C decreases while full-length (FL)-HPK1 increases. Accordingly, inhibition of proteolysis with the pan-caspase inhibitor Q-VD-OPh reduced HPK1 cleavage and enhanced DCS-induced differentiation of 40AF cells. The results indicate that FL-HPK1 is a positive regulator of vitamin D-induced differentiation in AML cells, but the cleaved HPK1 fragment inhibits differentiation. Thus, high HPK1 cleavage activity contributes to vitamin D resistance, and HPK1 has a dual role in AML cell differentiation.
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Affiliation(s)
- Xiangwen Chen-Deutsch
- Department of Pathology and Laboratory Medicine, UMDNJ-New Jersey Medical School, Newark, NJ, USA
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16
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Siligardi G, Ruzza P, Hussain R, Cesaro L, Brunati AM, Pinna LA, Donella-Deana A. The SH3 domain of HS1 protein recognizes lysine-rich polyproline motifs. Amino Acids 2011; 42:1361-70. [DOI: 10.1007/s00726-011-0831-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2010] [Accepted: 01/04/2011] [Indexed: 10/18/2022]
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17
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Phosphorylation of CARMA1 by HPK1 is critical for NF-kappaB activation in T cells. Proc Natl Acad Sci U S A 2009; 106:14508-13. [PMID: 19706536 DOI: 10.1073/pnas.0900457106] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Activation of the NF-kappaB pathway in T cells is required for induction of an adaptive immune response. Hematopoietic progenitor kinase (HPK1) is an important proximal mediator of T-cell receptor (TCR)-induced NF-kappaB activation. Knock-down of HPK1 abrogates TCR-induced IKKbeta and NF-kappaB activation, whereas active HPK1 leads to increased IKKbeta activity in T cells. Yet, the precise molecular mechanism of this process remains elusive. Here, we show that HPK1-mediated NF-kappaB activation is dependent on the adaptor protein CARMA1. HPK1 interacts with CARMA1 in a TCR stimulation-dependent manner and phosphorylates the linker region of CARMA1. Interestingly, the putative HPK1 phosphorylation sites in CARMA1 are different from known PKC consensus sites. Mutations of residues S549, S551, and S552 in CARMA1 abrogated phosphorylation of a CARMA1-linker construct by HPK1 in vitro. In addition, CARMA1 S551A or S5549A/S551A point mutants failed to restore HPK1-mediated and TCR-mediated NF-kappaB activation and IL-2 expression in CARMA1-deficient T cells. Thus, we identify HPK1 as a kinase specific for CARMA1 and suggest HPK1-mediated phosphorylation of CARMA1 as an additional regulatory mechanism tuning the NF-kappaB response upon TCR stimulation.
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18
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Wang H, Song X, Logsdon C, Zhou G, Evans DB, Abbruzzese JL, Hamilton SR, Tan TH, Wang H. Proteasome-mediated degradation and functions of hematopoietic progenitor kinase 1 in pancreatic cancer. Cancer Res 2009; 69:1063-70. [PMID: 19141650 DOI: 10.1158/0008-5472.can-08-1751] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Hematopoietic progenitor kinase 1 (HPK1) regulates stress responses, proliferation, and apoptosis in hematopoietic cells. In this study, we examined the expression, regulation, and functions of HPK1 in pancreatic ductal adenocarcinomas (PDA). We found that loss of HPK1 protein expression correlated significantly with the progression of pancreatic intraepithelial neoplasias (P = 0.001) and development of invasive PDA. Similarly, HPK1 protein was not expressed in any of eight PDA cell lines examined but was expressed in immortalized human pancreatic duct epithelial (HPDE) cells. There was no difference in HPK1 mRNA levels in PDA cell lines or primary PDA compared with those in HPDE cells or ductal epithelium in chronic pancreatitis and normal pancreas, respectively. Treatment of Panc-1 cells with a proteasome inhibitor, MG132, increased the HPK1 protein levels in a dose-dependent manner, suggesting that alteration in proteasome activity contributes to the loss of HPK1 protein expression in pancreatic cancer. Like the endogenous HPK1, both wild-type HPK1 and its kinase-dead mutant, HPK1-M46, overexpressed in Panc-1 cells, were also targeted by proteasome-mediated degradation. After MG132 withdrawal, wild-type HPK1 protein expression was markedly decreased within 24 hours, but kinase-dead HPK1 mutant protein expression was sustained for up to 96 hours. Therefore, HPK1 kinase activities were required for the loss of HPK1 protein in PDAs. Furthermore, restoring wild-type HPK1 protein in PDA cells led to the increase in p21 and p27 protein expression and cell cycle arrest. Thus, HPK1 may function as a novel tumor suppressor and its loss plays a critical role in pancreatic cancer.
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Affiliation(s)
- Hua Wang
- Department of Gastrointestinal Medical Oncology, The University of Texas MD Anderson Cancer, Baylor College of Medicine, Houston, Texas 77030, USA
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19
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Li T, Han D, Chen J, Yu XJ, Zhang GY. Neuroprotection against ischemic brain injury by knockdown of hematopietic progenitor kinase 1 expression. Neuroreport 2008; 19:647-51. [PMID: 18382279 DOI: 10.1097/wnr.0b013e3282f942a8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
In this study, we investigated the role of hematopietic progenitor kinase 1 (HPK1) in delayed neuronal damage after cerebral ischemia and the possible regulatory mechanisms of this event. Our data show that tyrosine phosphorylation of HPK1 was significantly increased at 6 h of ischemic-reperfusion compared with sham control. The increase in p-HPK1, p-MLK3, p-MKK7, and p-JNK3 was attenuated by HPK1 antisense oligodeoxynucleotides intra-cerebroventricular infusion, but not MS-ODNs or vehicle. Intracerebroventricular infusion of antisense oligodeoxynucleotides also increased the number of surviving pyramidal neurons, whereas MS-ODNs or vehicle (TE) groups had no effects. These results indicate that knockdown of HPK1 expression provides neuroprotection through downregulation activation of the MLK3-MKK7-JNK3 pathway following cerebral ischemia in the rat hippocampus CA1 subfield.
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Affiliation(s)
- Ting Li
- Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, China
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20
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Concepts of activated T cell death. Crit Rev Oncol Hematol 2008; 66:52-64. [DOI: 10.1016/j.critrevonc.2008.01.002] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2007] [Revised: 01/03/2008] [Accepted: 01/16/2008] [Indexed: 11/23/2022] Open
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21
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Sawasdikosol S, Pyarajan S, Alzabin S, Matejovic G, Burakoff SJ. Prostaglandin E2 activates HPK1 kinase activity via a PKA-dependent pathway. J Biol Chem 2007; 282:34693-9. [PMID: 17895239 DOI: 10.1074/jbc.m707425200] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Hematopoietic progenitor kinase 1 (HPK1) is a hematopoietic cell-restricted member of the Ste20 serine/threonine kinase super family. We recently reported that the immunosuppressive eicosanoid, prostaglandin E(2) (PGE(2)), is capable of activating HPK1 in T cells. In this report, we demonstrate that unlike the TCR-induced activation of HPK1 kinase activity, the induction of HPK1 catalytic activity by PGE(2) does not require the presence of phosphotyrosine-based signaling molecules such as Lck, ZAP-70, SLP-76, and Lat. Nor does the PGE(2)-induced HPK1 activation require the intermolecular interaction between its proline-rich regions and the SH3 domain-containing adaptor proteins, as required by the signaling from the TCR to HPK1. Instead, our study reveals that PGE(2) signal to HPK1 via a 3' -5 '-cyclic adenosine monophosphate-regulated, PKA-dependent pathway. Consistent with this observation, changing the serine 171 residue that forms the optimal PKA phosphorylation site within the "activation loop" of HPK1 to alanine completely prevents this mutant from responding to PGE(2)-generated stimulation signals. Moreover, the inability of HPK1 to respond to PGE(2) stimulation in PKA-deficient S49 cells further supports the importance of PKA in this signaling pathway. We speculate that this unique signaling pathway enables PGE(2) signals to engage a proven negative regulator of TCR signal transduction pathway and uses it to inhibit T cell activation.
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Affiliation(s)
- Sansana Sawasdikosol
- New York University School of Medicine, New York University Cancer Institute, New York, New York 10016-6402, USA.
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22
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Brenner D, Golks A, Becker M, Müller W, Frey CR, Novak R, Melamed D, Kiefer F, Krammer PH, Arnold R. Caspase-cleaved HPK1 induces CD95L-independent activation-induced cell death in T and B lymphocytes. Blood 2007; 110:3968-77. [PMID: 17712048 DOI: 10.1182/blood-2007-01-071167] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Life and death of peripheral lymphocytes is strictly controlled to maintain physiologic levels of T and B cells. Activation-induced cell death (AICD) is one mechanism to delete superfluous lymphocytes by restimulation of their immunoreceptors and it depends partially on the CD95/CD95L system. Recently, we have shown that hematopoietic progenitor kinase 1 (HPK1) determines T-cell fate. While full-length HPK1 is essential for NF-kappaB activation in T cells, the C-terminal fragment of HPK1, HPK1-C, suppresses NF-kappaB and sensitizes toward AICD by a yet undefined cell death pathway. Here we show that upon IL-2-driven expansion of primary T cells, HPK1 is converted to HPK1-C by a caspase-3 activity below the threshold of apoptosis induction. HPK1-C selectively blocks induction of NF-kappaB-dependent antiapoptotic Bcl-2 family members but not of the proapoptotic Bcl-2 family member Bim. Interestingly, T and B lymphocytes from HPK1-C transgenic mice undergo AICD independently of the CD95/CD95L system but involving caspase-9. Knock down of HPK1/HPK1-C or Bim by small interfering RNA shows that CD95L-dependent and HPK1/HPK1-C-dependent cell death pathways complement each other in AICD of primary T cells. Our results define HPK1-C as a suppressor of antiapoptotic Bcl-2 proteins and provide a molecular basis for our understanding of CD95L-independent AICD of lymphocytes.
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Affiliation(s)
- Dirk Brenner
- Tumor Immunology Program, German Cancer Research Center (DKFZ), Heidelberg, Germany
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23
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Seet BT, Berry DM, Maltzman JS, Shabason J, Raina M, Koretzky GA, McGlade CJ, Pawson T. Efficient T-cell receptor signaling requires a high-affinity interaction between the Gads C-SH3 domain and the SLP-76 RxxK motif. EMBO J 2007; 26:678-89. [PMID: 17235283 PMCID: PMC1794392 DOI: 10.1038/sj.emboj.7601535] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2006] [Accepted: 12/04/2006] [Indexed: 11/08/2022] Open
Abstract
The relationship between the binding affinity and specificity of modular interaction domains is potentially important in determining biological signaling responses. In signaling from the T-cell receptor (TCR), the Gads C-terminal SH3 domain binds a core RxxK sequence motif in the SLP-76 scaffold. We show that residues surrounding this motif are largely optimized for binding the Gads C-SH3 domain resulting in a high-affinity interaction (K(D)=8-20 nM) that is essential for efficient TCR signaling in Jurkat T cells, since Gads-mediated signaling declines with decreasing affinity. Furthermore, the SLP-76 RxxK motif has evolved a very high specificity for the Gads C-SH3 domain. However, TCR signaling in Jurkat cells is tolerant of potential SLP-76 crossreactivity, provided that very high-affinity binding to the Gads C-SH3 domain is maintained. These data provide a quantitative argument that the affinity of the Gads C-SH3 domain for SLP-76 is physiologically important and suggest that the integrity of TCR signaling in vivo is sustained both by strong selection of SLP-76 for the Gads C-SH3 domain and by a capacity to buffer intrinsic crossreactivity.
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Affiliation(s)
- Bruce T Seet
- Centre for Systems Biology, Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
- Department of Molecular and Medical Genetics. University of Toronto, Toronto, Ontario, Canada
| | - Donna M Berry
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
| | - Jonathan S Maltzman
- Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, PA, USA
- Department of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Jacob Shabason
- Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, PA, USA
| | - Monica Raina
- Centre for Systems Biology, Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - Gary A Koretzky
- Abramson Family Cancer Research Institute, University of Pennsylvania, Philadelphia, PA, USA
- Department of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - C Jane McGlade
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
| | - Tony Pawson
- Centre for Systems Biology, Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
- Department of Molecular and Medical Genetics. University of Toronto, Toronto, Ontario, Canada
- Centre for Systems Biology, Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Ave., Room 1084, Toronto, Ontario, Canada M5G 1X5. Tel: +1 416 586 4800 ext 8262; Fax: +1 416 586 8869; E-mail:
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24
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Shui JW, Boomer JS, Han J, Xu J, Dement GA, Zhou G, Tan TH. Hematopoietic progenitor kinase 1 negatively regulates T cell receptor signaling and T cell-mediated immune responses. Nat Immunol 2006; 8:84-91. [PMID: 17115060 DOI: 10.1038/ni1416] [Citation(s) in RCA: 136] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2006] [Accepted: 10/26/2006] [Indexed: 11/09/2022]
Abstract
HPK1 is a Ste20-related serine-threonine kinase that inducibly associates with the adaptors SLP-76 and Gads after T cell receptor (TCR) signaling. Here, HPK1 deficiency resulted in enhanced TCR-induced phosphorylation of SLP-76, phospholipase C-gamma1 and the kinase Erk, more-persistent calcium flux, and increased production of cytokines and antigen-specific antibodies. Furthermore, HPK1-deficient mice were more susceptible to experimental autoimmune encephalomyelitis. Although the interaction between SLP-76 and Gads was unaffected, the inducible association of SLP-76 with 14-3-3tau (a phosphorylated serine-binding protein and negative regulator of TCR signaling) was reduced in HPK1-deficient T cells after TCR stimulation. HPK1 phosphorylated SLP-76 and induced the interaction of SLP-76 with 14-3-3tau. Our results indicate that HPK1 negatively regulates TCR signaling and T cell-mediated immune responses.
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Affiliation(s)
- Jr-Wen Shui
- Department of Immunology, Baylor College of Medicine, Houston, Texas 77030, USA
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25
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Bunnell SC, Singer AL, Hong DI, Jacque BH, Jordan MS, Seminario MC, Barr VA, Koretzky GA, Samelson LE. Persistence of cooperatively stabilized signaling clusters drives T-cell activation. Mol Cell Biol 2006; 26:7155-66. [PMID: 16980618 PMCID: PMC1592897 DOI: 10.1128/mcb.00507-06] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Antigen recognition triggers the recruitment of the critical adaptor protein SLP-76 to small macromolecular clusters nucleated by the T-cell receptor (TCR). These structures develop rapidly, in parallel with TCR-induced increases in tyrosine phosphorylation and cytosolic calcium, and are likely to contribute to TCR-proximal signaling. Previously, we demonstrated that these SLP-76-containing clusters segregate from the TCR and move towards the center of the contact interface. Neither the function of these clusters nor the structural requirements governing their persistence have been examined extensively. Here we demonstrate that defects in cluster assembly and persistence are associated with defects in T-cell activation in the absence of Lck, ZAP-70, or LAT. Clusters persist normally in the absence of phospholipase C-gamma1, indicating that in the absence of a critical effector, these structures are insufficient to drive T-cell activation. Furthermore, we show that the critical adaptors LAT and Gads localize with SLP-76 in persistent clusters. Mutational analyses of LAT, Gads, and SLP-76 indicated that multiple domains within each of these proteins contribute to cluster persistence. These data indicate that multivalent cooperative interactions stabilize these persistent signaling clusters, which may correspond to the functional complexes predicted by kinetic proofreading models of T-cell activation.
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Affiliation(s)
- Stephen C Bunnell
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, NCI, National Institutes of Health, Bethesda, Maryland, USA.
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26
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Arnold R, Frey CR, Müller W, Brenner D, Krammer PH, Kiefer F. Sustained JNK signaling by proteolytically processed HPK1 mediates IL-3 independent survival during monocytic differentiation. Cell Death Differ 2006; 14:568-75. [PMID: 17024227 DOI: 10.1038/sj.cdd.4402042] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
We studied monocytic differentiation of primary mouse progenitor cells to understand molecular mechanisms of differentiation. We found a tightly controlled non-apoptotic activation of caspase-3 that correlated with differentiation. Although caspase activity was already detected during monocytic differentiation, a caspase-3 target has not been identified yet. We show that hematopoietic progenitor kinase 1 (HPK1) is processed towards its N- and C-terminal fragments during monocytic differentiation. While HPK1 is an immunoreceptor-proximal kinase in T and B cells, its role in myeloid cells is elusive. Here, we show that the N-terminal cleavage product, HPK1-N, comprising the kinase domain, confers progenitor cell survival independent of the growth factor IL-3. Furthermore, HPK1-N causes differentiation of progenitor cells towards the monocytic lineage. In contrast to full-length kinase, HPK1-N is constitutively active causing sustained JNK activation, Bad phosphorylation and survival. Blocking of caspase activity during differentiation of primary mouse progenitor cells leads to reduced HPK1-N levels, suppressed JNK activity and attenuated monocytic differentiation. Our work explains growth factor-independent survival during monocytic differentiation by caspase-mediated processing of HPK1 towards HPK1-N.
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Affiliation(s)
- R Arnold
- Max-Planck-Institute for Physiological and Clinical Research, WG Kerckhoff-Institute, Parkstrasse 1, D-61231 Bad Nauheim, Germany.
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27
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Chen R, Latour S, Shi X, Veillette A. Association between SAP and FynT: Inducible SH3 domain-mediated interaction controlled by engagement of the SLAM receptor. Mol Cell Biol 2006; 26:5559-68. [PMID: 16847311 PMCID: PMC1592776 DOI: 10.1128/mcb.00357-06] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
SAP is an intracellular adaptor molecule composed almost exclusively of an SH2 domain. It is mutated in patients with X-linked lymphoproliferative disease, a human immunodeficiency. Several immune abnormalities were also identified in SAP-deficient mice. By way of its SH2 domain, SAP interacts with tyrosine-based motifs in the cytoplasmic domain of SLAM family receptors. SAP promotes SLAM family receptor-induced protein tyrosine phosphorylation, due to its capacity to recruit the Src-related kinase FynT. This unusual property relies on the existence of a second binding surface in the SAP SH2 domain, centered on arginine 78 of SAP, that binds directly to the FynT SH3 domain. Herein, we wanted to further understand the mechanisms controlling the interaction between SLAM-SAP and FynT. Our experiments showed that, unlike conventional associations mediated by SH3 domains, the interaction of the FynT SH3 domain with SLAM-SAP was strictly inducible. It was absolutely dependent on engagement of SLAM by extracellular ligands. We obtained evidence that this inducibility was not due to increased binding of SLAM to SAP following SLAM engagement. Furthermore, it could occur independently of any appreciable SLAM-dependent biochemical signal. In fact, our data indicated that the induced association of the FynT SH3 domain with SLAM-SAP was triggered by a change in the conformation of SLAM-associated SAP caused by SLAM engagement. Together, these data elucidate further the events initiating SLAM-SAP signaling in immune cells. Moreover, they identify a strictly inducible interaction mediated by an SH3 domain.
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Affiliation(s)
- Riyan Chen
- Laboratory of Molecular Oncology, Clinical Research Institute of Montreal, Montréal, Québec, Canada
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28
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Brenner D, Golks A, Kiefer F, Krammer PH, Arnold R. Activation or suppression of NFkappaB by HPK1 determines sensitivity to activation-induced cell death. EMBO J 2005; 24:4279-90. [PMID: 16341093 PMCID: PMC1356335 DOI: 10.1038/sj.emboj.7600894] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2005] [Accepted: 11/09/2005] [Indexed: 12/16/2022] Open
Abstract
Restimulation of the T-cell receptor (TCR) in activated T cells induces CD95 (Fas/Apo-1)-mediated activation-induced cell death (AICD). The TCR-proximal mechanisms leading to AICD are elusive. Here we characterize hematopoietic progenitor kinase 1 (HPK1) as a differentially regulated TCR-proximal signaling protein involved in AICD of primary T cells. We show that HPK1 is a functional component of the endogenous IkappaB kinase (IKK) complex and is crucial for TCR-mediated NFkappaB activation. While full-length HPK1 enhances IKKbeta phosphorylation, siRNA-mediated knockdown of HPK1 blunts TCR-mediated NFkappaB activation and increases cell death. We also demonstrate proteolytic processing of HPK1 into HPK1-C, specifically in AICD-sensitive primary T cells. The cleavage product HPK1-C sequesters the inactive IKK complex and suppresses NFkappaB upon TCR restimulation by binding to IKKalpha and IKKbeta. T cells of HPK1-C transgenic mice are sensitized towards TCR-mediated AICD. Consequently, preventing HPK1-C generation in primary T cells by siRNA-mediated knockdown results in decreased AICD. Thus, these results show a novel mechanism of sensitization of T lymphocytes towards AICD by suppression of NFkappaB, and propose that HPK1 is a life/death switch in T lymphocytes.
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Affiliation(s)
- Dirk Brenner
- Tumor Immunology Program, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Alexander Golks
- Tumor Immunology Program, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | | | - Peter H Krammer
- Tumor Immunology Program, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Rüdiger Arnold
- Tumor Immunology Program, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Tumor Immunology Program, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69112 Heidelberg, Germany. Tel.: +49 6221 423769; Fax: +49 6221 411715; E-mail:
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29
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Abstract
Hematopoietic progenitor kinase 1 (HPK1 or MAP4K1) is a hematopoietic-specific mammalian STE20-like protein serine/threonine kinase, comprised of a STE20-like kinase domain in its N-terminus, four proline-rich motifs, a caspase cleavage site, and a distal C-terminal Citron homology domain. HPK1 is involved in many cellular signaling cascades that include MAPK signaling, antigen receptor signaling, apoptosis, growth factor signaling, and cytokine signaling. HPK1 binds many adaptor proteins including members of the Grb2 family, Nck family, Crk family, SLP-76 family, and actin-binding adaptors like HIP-55. HPK1 tyrosine phosphorylation and kinase activation depend on the presence of adaptor proteins. Adaptor proteins are required not only for linking HPK1 to cell surface receptors like the EGFR, but also for downstream gene transcription like NFAT, AP-1 and IL-2. The HPK1 association with Crk, CrkL, and HIP-55 mediate HPK1-dependent c-Jun N-terminal kinase (JNK) activation, while the association of HPK1 with SLP-76, Gads, CrkL, Grb2, and Grap affect T- and B-cell dependent gene transcription. Interestingly, HPK1 has been implicated in both increasing and decreasing NFAT, AP-1, and IL-2 gene transcription in T-cells where adaptor proteins play a key role. Lastly, HPK1 will phosphorylate Crk and CrkL, in vitro, which presents a novel possibility for the regulation of adaptor proteins and downstream signaling events.
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Affiliation(s)
- Jonathan S Boomer
- Department of Immunology, Baylor College of Medicine, Houston, Texas 77030-3498, USA
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30
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Yankee TM, Draves KE, Clark EA. Expression and function of the adaptor protein Gads in murine B cells. Eur J Immunol 2005; 35:1184-92. [PMID: 15761845 DOI: 10.1002/eji.200425507] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Nearly all hematopoietic receptors are dependent on adaptor proteins for the activation of downstream signaling pathways. The Gads adaptor protein is expressed in many hematopoietic tissues, including bone marrow, lymph node, and spleen. Using intracellular staining, we detected Gads protein in a number cells, including B cells, T cells, NK cells, monocytes, and plasmacytoid DC, but not in macrophages, neutrophils, or monocyte-derived DC. In the B cell compartment, Gads was first expressed after immature B cells leave the bone marrow and was down-regulated after B cell antigen receptor (BCR) ligation. Female Gads(-/-) mice had increased numbers of splenic B cells, as compared to female Gads(+/+) mice, suggesting a role for Gads in B cell homeostasis. Although B cell production and turnover of splenic B cell subsets appeared normal in Gads(-/-) mice, homeostatic proliferation was significantly impaired in Gads(-/-) B cells. Whereas BCR ligation can induce apoptosis in wild-type transitional stage 1 (T1) B cells, Gads(-/-) T1 B cells were resistant to BCR-induced apoptosis. Gads(-/-) B cells also showed increased BCR-mediated calcium mobilization. We conclude that Gads may have a negative regulatory role in signaling through survival pathways, and is necessary for normal homeostatic proliferation in B cells.
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Affiliation(s)
- Thomas M Yankee
- Department of Immunology, University of Washington, Seattle, USA.
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31
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Arnold R, Patzak IM, Neuhaus B, Vancauwenbergh S, Veillette A, Van Lint J, Kiefer F. Activation of hematopoietic progenitor kinase 1 involves relocation, autophosphorylation, and transphosphorylation by protein kinase D1. Mol Cell Biol 2005; 25:2364-83. [PMID: 15743830 PMCID: PMC1061595 DOI: 10.1128/mcb.25.6.2364-2383.2005] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Adaptive immune signaling can be coupled to stress-activated protein kinase (SAPK)/c-Jun N-terminal kinase (JNK) and NF-kappaB activation by the hematopoietic progenitor kinase 1 (HPK1), a mammalian hematopoiesis-specific Ste20 kinase. To gain insight into the regulation of leukocyte signal transduction, we investigated the molecular details of HPK1 activation. Here we demonstrate the capacity of the Src family kinase Lck and the SLP-76 family adaptor protein Clnk (cytokine-dependent hematopoietic cell linker) to induce HPK1 tyrosine phosphorylation and relocation to the plasma membrane, which in lymphocytes results in recruitment of HPK1 to the contact site of antigen-presenting cell (APC)-T-cell conjugates. Relocation and clustering of HPK1 cause its enzymatic activation, which is accompanied by phosphorylation of regulatory sites in the HPK1 kinase activation loop. We show that full activation of HPK1 is dependent on autophosphorylation of threonine 165 and phosphorylation of serine 171, which is a target site for protein kinase D (PKD) in vitro. Upon T-cell receptor stimulation, PKD robustly augments HPK1 kinase activity in Jurkat T cells and enhances HPK1-driven SAPK/JNK and NF-kappaB activation; conversely, antisense down-regulation of PKD results in reduced HPK1 activity. Thus, activation of major lymphocyte signaling pathways via HPK1 involves (i) relocation, (ii) autophosphorylation, and (iii) transphosphorylation of HPK1 by PKD.
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Affiliation(s)
- Rüdiger Arnold
- Max Planck Institute for Molecular Biomedicine, Von-Esmarch-Strasse 56, D-48149 Münster, Germany
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32
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Zhou G, Boomer JS, Tan TH. Protein Phosphatase 4 Is a Positive Regulator of Hematopoietic Progenitor Kinase 1. J Biol Chem 2004; 279:49551-61. [PMID: 15364934 DOI: 10.1074/jbc.m410317200] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Hematopoietic progenitor kinase 1 (HPK1) is a hematopoietic specific mammalian Ste20-like protein kinase and has been implicated in many cellular signaling pathways including T cell receptor (TCR) signaling. However, little is known about the in vivo regulation of HPK1. We present evidence that HPK1 is positively regulated by protein phosphatase 4 (PP4; also called PPX and PPP4), a serine/threonine phosphatase. We found that PP4 interacted with HPK1 and that the proline-rich region of HPK1 was necessary and sufficient for this interaction. We also found that PP4 had phosphatase activity toward HPK1 in vivo and that co-transfection of PP4 with HPK1 resulted in specific kinase activation of HPK1. Moreover, we found that the PP4-induced HPK1 kinase activation was accompanied by an increase in protein expression of HPK1. Pulse-chase analysis showed that PP4 increased the half-life of HPK1. Further studies showed that HPK1 was subject to regulation by ubiquitination and ubiquitin-targeted degradation and that PP4 inhibited HPK1 ubiquitination. In addition, we found that TCR stimulation enhanced the PP4-HPK1 interaction and that wild-type PP4 enhanced, whereas a phosphatase-dead PP4 mutant inhibited, TCR-induced activation of HPK1 in Jurkat T cells. Combined with the observation that PP4 enhanced HPK1-induced JNK activation, our studies identify PP4 as a positive regulator for HPK1 and the HPK1-JNK signaling pathway.
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Affiliation(s)
- Guisheng Zhou
- Department of Immunology, Baylor College of Medicine, Houston, Texas 77030, USA
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33
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Lewitzky M, Harkiolaki M, Domart MC, Jones EY, Feller SM. Mona/Gads SH3C binding to hematopoietic progenitor kinase 1 (HPK1) combines an atypical SH3 binding motif, R/KXXK, with a classical PXXP motif embedded in a polyproline type II (PPII) helix. J Biol Chem 2004; 279:28724-32. [PMID: 15100220 DOI: 10.1074/jbc.m402745200] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Hematopoietic progenitor kinase 1 (HPK1) is implicated in signaling downstream of the T cell receptor. Its non-catalytic, C-terminal half contains several prolinerich motifs, which have been shown to interact with different SH3 domain-containing adaptor proteins in vitro. One of these, Mona/Gads, was also shown to bind HPK1 in mouse T cells in vivo. The region of HPK1 that binds to the Mona/Gads C-terminal SH3 domain has been mapped and shows only very limited similarity to a recently identified high affinity binding motif in SLP-76, another T-cell adaptor. Using isothermal titration calorimetry and x-ray crystallography, the binding of the HPK1 motif to Mona/Gads SH3C has now been characterized in molecular detail. The results indicate that although charge interactions through an RXXK motif are essential for complex formation, a PXXP motif in HPK1 strongly complements binding. This unexpected binding mode therefore differs considerably from the previously described interaction of Mona/Gads SH3C with SLP-76. The crystal structure of the complex highlights the great versatility of SH3 domains, which allows interactions with very different proteins. This currently limits our ability to categorize SH3 binding properties by simple rules.
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Affiliation(s)
- Marc Lewitzky
- Cancer Research UK Cell Signalling Group, Molecular Oncology Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom
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34
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Abstract
Recent advances have been made in understanding the basis of T-cell signaling with the identification of hematopoeitic-specific adaptor proteins, or molecular scaffolds that facilitate protein complex formation and the integration of signals from the surface of T cells. Their potential relevance as targets in the modulation of transplantation relates to their immune-cell-specific expression and their ability to integrate signals needed for T-cell/APC conjugate formation, cytokine production and the clonal expansion of T cells. While LAT, GADS and SLP-76 are needed for TcR-induced cytokine production, the adaptors ADAP, VAV and SKAP-55 play specialized roles in the regulation of integrin adhesion and conjugation. Given the importance of these functions to the reactivity of T cells to allodeterminants of tissue grafts (GvH), and in the recognition and destruction of leukemic cells (GvL), these adaptors represent a new generation of potential targets in the modulation of transplantation.
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Affiliation(s)
- Christopher E Rudd
- Department of Immunology, Faculty of Medicine, Imperial College London, London, UK.
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35
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Harkiolaki M, Lewitzky M, Gilbert RJC, Jones EY, Bourette RP, Mouchiroud G, Sondermann H, Moarefi I, Feller SM. Structural basis for SH3 domain-mediated high-affinity binding between Mona/Gads and SLP-76. EMBO J 2003; 22:2571-82. [PMID: 12773374 PMCID: PMC156755 DOI: 10.1093/emboj/cdg258] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
SH3 domains are protein recognition modules within many adaptors and enzymes. With more than 500 SH3 domains in the human genome, binding selectivity is a key issue in understanding the molecular basis of SH3 domain interactions. The Grb2-like adaptor protein Mona/Gads associates stably with the T-cell receptor signal transducer SLP-76. The crystal structure of a complex between the C-terminal SH3 domain (SH3C) of Mona/Gads and a SLP-76 peptide has now been solved to 1.7 A. The peptide lacks the canonical SH3 domain binding motif P-x-x-P and does not form a frequently observed poly-proline type II helix. Instead, it adopts a clamp-like shape around the circumfence of the SH3C beta-barrel. The central R-x-x-K motif of the peptide forms a 3(10) helix and inserts into a negatively charged double pocket on the SH3C while several other residues complement binding through hydrophobic interactions, creating a short linear SH3C binding epitope of uniquely high affinity. Interestingly, the SH3C displays ion-dependent dimerization in the crystal and in solution, suggesting a novel mechanism for the regulation of SH3 domain functions.
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Affiliation(s)
- Maria Harkiolaki
- Cancer Research UK Cell Signalling Group and Weatherall Institute of Molecular Medicine, Oxford, UK
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36
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Abstract
Adaptor proteins are unique, as they contain modular domains and lack intrinsic enzymatic activity. These proteins are scaffolds for the organization of macromolecular complexes and they recruit other proteins for correct localization during molecular signal transduction. Numerous recent advances have been made through the elucidation of new adaptor proteins and the recognition of novel functions for previously identified molecules. In addition, the roles of adaptors in both the positive and negative regulation of lymphocyte activation have been further clarified.
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Affiliation(s)
- Erin Janssen
- Department of Immunology, Duke University Medical Center, Durham, North Carolina 27710, USA
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Yamasaki S, Nishida K, Sakuma M, Berry D, McGlade CJ, Hirano T, Saito T. Gads/Grb2-mediated association with LAT is critical for the inhibitory function of Gab2 in T cells. Mol Cell Biol 2003; 23:2515-29. [PMID: 12640133 PMCID: PMC150736 DOI: 10.1128/mcb.23.7.2515-2529.2003] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
A docking protein, Gab2, is recruited to the vicinity of the TCR complex and inhibits downstream signaling by interaction with negative regulators. However, the molecular mechanisms of this recruitment remain unclear. We have found that Gab2 associates with LAT upon TCR stimulation and that LAT is essential for Gab2 phosphorylation. By analysis of several Gab2 mutants, the c-Met binding domain (MBD) of Gab2 was found to be both necessary and sufficient for stimulation-induced LAT binding. Within the MBD domain, a novel Grb2 SH3 binding motif, PXXXR, is critical for constitutive association with Gads/Grb2. Through this association, Gab2 is recruited to the lipid raft after TCR ligation and exerts inhibitory function. The in vivo significance of this association is illustrated by the fact that T-cell responses are impaired in transgenic mice expressing wild-type Gab2 but not in mice expressing mutant Gab2 lacking the motif. Furthermore, T cells from Gab2-deficient mice showed enhanced proliferative responses upon TCR stimulation. These results indicate that Gads/Grb2-mediated LAT association is critical for the inhibitory function of Gab2, implying that Gab2 induced in stimulated T cells may exert an efficient negative feedback loop by recruiting inhibitory molecules to the lipid raft and competing with SLP-76 through Gads binding.
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Affiliation(s)
- Sho Yamasaki
- Department of Molecular Genetics, Graduate School of Medicine, Chiba University, Chuo-ku, Chiba 260-8670, Japan
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Iwashima M. Kinetic perspectives of T cell antigen receptor signaling. A two-tier model for T cell full activation. Immunol Rev 2003; 191:196-210. [PMID: 12614361 DOI: 10.1034/j.1600-065x.2003.00024.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
T-cell activation consists of multiple layers of signaling events. Interleukin-2 production is of interest for many, since its expression determines a critical difference between partial and full T-cell activation. To achieve full activation of T cells, it is necessary for the T-cell antigen receptor (TCR) to be engaged for an extended period of time. However, why extended stimulation is required for full T-cell activation is not understood at the molecular level. In this review, orchestrated events of TCR signal transduction will be analyzed in a kinetic manner and connected toward the understanding of the mechanism of T-cell activation. Based on recent results, a model of the mechanism that dictates the threshold between partial and full T-cell activation is proposed.
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Affiliation(s)
- Makio Iwashima
- Institute of Molecular Medicine and Genetics, Medical College of Georgia, Augusta, GA 30912-2600, USA.
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39
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Schulze-Luehrmann J, Santner-Nanan B, Jha MK, Schimpl A, Avots A, Serfling E. Hematopoietic progenitor kinase 1 supports apoptosis of T lymphocytes. Blood 2002; 100:954-60. [PMID: 12130508 DOI: 10.1182/blood-2002-01-0089] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Hematopoietic progenitor kinase 1 (HPK1) is a member of germinal center kinases that is predominantly expressed in hematopoietic cells and transiently activated by T-cell receptor (TCR) triggering. We show here that HPK1 supports apoptosis of T cells. When HPK1 was overexpressed in murine CD4(+) T cells, a substantial increase was observed in spontaneous and TCR/CD3-mediated apoptosis as well as in Fas ligand (FasL) expression. In H2O2-treated EL-4 thymoma cells, which show an increase in reactive oxygen species (ROS) and apoptosis, overexpression of HPK1 enhanced ROS-mediated apoptosis, whereas expression of HPK1 antisense (AS) RNA impaired apoptosis. HPK1 expression also led to a sustained increase in c-Jun N-terminal kinase (JNK) activity, suggesting that JNK activation contributes to the HPK1-mediated apoptosis in H2O2-treated EL-4 cells. Under the same conditions, a rapid cleavage of HPK1 was observed, and overexpression of N- and C-terminal cleavage products in CD4(+) T cells resulted in, similar to full-length HPK1, an increase in apoptosis. In agreement with published data, we show that the C-terminal portion of HPK1 suppresses IkappaBalpha degradation, thereby inhibiting nuclear factor (NF)-kappaB activation. These findings suggest that by inhibiting the antiapoptotic action of NF-kappaB and inducing the proapoptotic activity of JNK, OHPK1 supports apoptosis in T cells.
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Affiliation(s)
- Jan Schulze-Luehrmann
- Department of Molecular Pathology, Institute of Pathology, D-97080 Wuerzburg, Germany
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40
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Abstract
Engagement of the T cell antigen receptor (TCR) leads to a complex series of molecular changes at the plasma membrane, in the cytoplasm, and at the nucleus that lead ultimately to T cell effector function. Activation at the TCR of a set of protein tyrosine kinases (PTKs) is an early event in this process. This chapter reviews some of the critical substrates of these PTKs, the adapter proteins that, following phosphorylation on tyrosine residues, serve as binding sites for many of the critical effector enzymes and other adapter proteins required for T cell activation. The role of these adapters in binding various proteins, the interaction of adapters with plasma membrane microdomains, and the function of adapter proteins in control of the cytoskeleton are discussed.
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Affiliation(s)
- Lawrence E Samelson
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 37 Convent Drive, Building 37, Room 1E24, Bethesda, Maryland, 20892-4255, USA.
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41
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Bourgin C, Bourette RP, Arnaud S, Liu Y, Rohrschneider LR, Mouchiroud G. Induced expression and association of the Mona/Gads adapter and Gab3 scaffolding protein during monocyte/macrophage differentiation. Mol Cell Biol 2002; 22:3744-56. [PMID: 11997510 PMCID: PMC133813 DOI: 10.1128/mcb.22.11.3744-3756.2002] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mona/Gads is a Grb2-related, Src homology 3 (SH3) and SH2 domain-containing adapter protein whose expression is restricted to cells of hematopoietic lineage (i.e., monocytes and T lymphocytes). During monocyte/macrophage differentiation, Mona is induced and interacts with the macrophage colony-stimulating factor receptor, M-CSFR (also called Fms), suggesting that Mona could be involved in developmental signaling downstream of the M-CSFR by recruiting additional signaling proteins to the activated receptor. Our present results identify Mona as a specific partner protein for the DOS/Gab family member Gab3 in monocytic/macrophage development. Mona does not interact with Gab2; however, Gab3 also forms a complex with the Mona-related adapter Grb2. Glutathione S-transferase pull-down experiments demonstrate that the Mona and Gab3 interaction utilizes the carboxy-terminal SH3 domain of Mona and the atypical proline-rich domain of Gab3. Mona is known to interact with the phosphorylated Y697 site of the M-CSFR. The M-CSFR mutation Y697F exhibited qualitative and quantitative abnormalities in receptor and Gab3 tyrosine phosphorylation, and Mona induction was greatly reduced. The Y807F M-CSFR mutation is defective in differentiation signaling, but not growth signaling, and also fails to induce Mona protein expression. During M-CSF-stimulated macrophage differentiation of mouse bone marrow cells, Mona and Gab3 expression is coinduced, these proteins interact, and Mona engages in multimolecular complexes. These data suggest that association of Mona and Gab3 plays a specific role in mediating the M-CSFR differentiation signal.
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Affiliation(s)
- Caroline Bourgin
- Centre de Génétique Moléculaire et Cellulaire, UMR CNRS 5534, 69622 Villeurbanne Cedex, France
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42
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Burack WR, Cheng AM, Shaw AS. Scaffolds, adaptors and linkers of TCR signaling: theory and practice. Curr Opin Immunol 2002; 14:312-6. [PMID: 11973128 DOI: 10.1016/s0952-7915(02)00347-3] [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: 11/16/2022]
Abstract
Four non-enzymatic proteins form the structural core of the TCR signaling machinery, linking antigen-receptor activation to signaling. These four proteins, each with well defined protein-protein interaction domains, include three 'scaffolds' (LAT, SLP-76 and SLAP-130/Fyb/ADAP and a 'pure adaptor' (GADS). The biological functions of many distinct protein-protein interaction domains have been dissected through a methodological series of knockout and reconstitution experiments. In reviewing these recent advances, we attempt to address two questions often asked by immunologists not familiar with the field: what do scaffolds/adaptors/linkers do; and what do these terms mean?
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Affiliation(s)
- W Richard Burack
- Department of Pathology and Immunology, Washington University School of Medicine, St Louis, MO 63110, USA
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43
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Abstract
Using specific cell surface receptors lymphocytes continuously sample their environment. Maturation of the immune system and initiation of a specific immune response rely on an array of extracellular cues that elicit complex intracellular biochemical signals. Essential molecules involved in signal transduction from immunoreceptors have emerged. After immunoreceptor engagement a core signaling complex is assembled comprising cytoplasmic immunoreceptor chains, kinases of the Src and ZAP70 families and various cytoplasmic and transmembrane adaptor molecules. Further effectors nucleate onto this complex evoking the characteristic responses of lymphocyte activation. Successful maturation of T cells into effector cells relies on the presence of a persistent stimulus presented in an appropriate extracellular environment. Encounter of MHC presented antigenic peptides and their cognate T cell receptors (TCRs) results in the formation of a nanometer intercellular gap between T cells and antigen presenting cells, which is now commonly referred to as the immunological synapse. The synapse is believed to sustain persistent TCR engagement. Its formation requires massive changes in T cell cytoskeletal architecture which essentially relies on signals provided by costimulatory molecules. The well orchestrated interplay between TCR and costimulatory signals decides about successful immune response and tolerance induction or immune failure and autoimmunity.
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Affiliation(s)
- Friedemann Kiefer
- Max-Planck-Institute for Physiological and Clinical Research, WG. Kerckhoff-Jnstitute, Bad Nauheim, Germany.
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44
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Hussain SF, Anderson CF, Farber DL. Differential SLP-76 expression and TCR-mediated signaling in effector and memory CD4 T cells. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2002; 168:1557-65. [PMID: 11823482 DOI: 10.4049/jimmunol.168.4.1557] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We present in this study novel findings on TCR-mediated signaling in naive, effector, and memory CD4 T cells that identify critical biochemical markers to distinguish these subsets. We demonstrate that relative to naive CD4 T cells, memory CD4 T cells exhibit a profound decrease in expression of the linker/adapter molecule SLP-76, while effector T cells express normal to elevated levels of SLP-76. The reduced level of SLP-76 is memory CD4 T cells is coincident with reduced phosphorylation overall, yet the residual SLP-76 couples to a subset of TCR-associated linker molecules, leading to downstream mitogen-activated protein (MAP) kinase activation. By contrast, effector CD4 T cells strongly phosphorylate SLP-76, linker for activation of T cells, and additional Grb2-coupled proteins, exhibit increased associations of SLP-76 to phosphorylated linkers, and hyperphosphorylate downstream Erk1/2 MAP kinases. Our results suggest distinct coupling of signaling intermediates to the TCR in naive, effector, and memory CD4 T cells. Whereas effector CD4 T cells amplify existing TCR signaling events accounting for rapid effector responses, memory T cells engage fewer signaling intermediates to efficiently link TCR triggering directly to downstream MAP kinase activation.
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Affiliation(s)
- S Farzana Hussain
- Department of Surgery, University of Maryland, Baltimore, MD 21201, USA
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45
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Affiliation(s)
- Liping Geng
- Department of Cancer Immunology and AIDS, Dana Farber Cancer Institute, Harvard Medical School, Boston, MA, USA
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46
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Sauer K, Liou J, Singh SB, Yablonski D, Weiss A, Perlmutter RM. Hematopoietic progenitor kinase 1 associates physically and functionally with the adaptor proteins B cell linker protein and SLP-76 in lymphocytes. J Biol Chem 2001; 276:45207-16. [PMID: 11487585 DOI: 10.1074/jbc.m106811200] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
B cell linker protein (BLNK) is a SLP-76-related adaptor protein essential for signal transduction from the BCR. To identify components of BLNK-associated signaling pathways, we performed a phosphorylation-dependent yeast two-hybrid analysis using BLNK probes. Here we report that the serine/threonine kinase hematopoietic progenitor kinase 1 (HPK1), which is activated upon antigen-receptor stimulation and which has been implicated in the regulation of MAP kinase pathways, interacts physically and functionally with BLNK in B cells and with SLP-76 in T cells. This interaction requires Tyr(379) of HPK1 and the Src homology 2 (SH2) domain of BLNK/SLP-76. Via homology modeling, we defined a consensus binding site within ligands for SLP family SH2 domains. We further demonstrate that the SH2 domain of SLP-76 participates in the regulation of AP-1 and NFAT activation in response to T cell receptor (TCR) stimulation and that HPK1 inhibits AP-1 activation in a manner partially dependent on its interaction with SLP-76. Our data are consistent with a model in which full activation of HPK1 requires its own phosphorylation on tyrosine and subsequent interaction with adaptors of the SLP family, providing a mechanistic basis for the integration of this kinase into antigen receptor signaling cascades.
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Affiliation(s)
- K Sauer
- Department of Immunology and Rheumatology and Department of Molecular Systems, Merck Research Laboratories, Rahway, New Jersey 07065, USA.
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47
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Abstract
Gads is a member of the family of SH2 and SH3 domain containing adaptor proteins that is expressed specifically in hematopoietic cells and functions in the coordination of tyrosine kinase mediated signal transduction. Gads plays a critical role in signalling from the T cell receptor by promoting the formation of a complex between SLP-76 and LAT. This complex couples the T cell receptor to Ras through a novel pathway involving PLC-gamma1, Tec family kinases, and RasGRP. Studies with Gads-deficient mice have highlighted its importance for thymocyte proliferation during T cell maturation. Emerging evidence suggests that Gads may also play additional roles in antigen-receptor signalling and receptor tyrosine kinase mediated signalling in other hematopoietic lineages. Gads is a unique member of the Grb2 adaptor family, because its activity can be regulated by caspase cleavage. Gads nucleates multi-protein complexes that are required for tyrosine kinase-dependent signalling in immune cells and may also represent a point of modulation for these pathways through the activation of caspase-dependent signalling events.
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Affiliation(s)
- S K Liu
- The Arthur and Sonia Labatt Brain Tumour Research Centre, The Hospital for Sick Children and Department of Medical Biophysics, University of Toronto, 555 University Avenue, Toronto, Ontario, Canada M5G 1X8
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48
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Yu J, Riou C, Davidson D, Minhas R, Robson JD, Julius M, Arnold R, Kiefer F, Veillette A. Synergistic regulation of immunoreceptor signaling by SLP-76-related adaptor Clnk and serine/threonine protein kinase HPK-1. Mol Cell Biol 2001; 21:6102-12. [PMID: 11509653 PMCID: PMC87327 DOI: 10.1128/mcb.21.18.6102-6112.2001] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Recently, the identification of Clnk, a third member of the SLP-76 family of adaptors expressed exclusively in cytokine-stimulated hemopoietic cells, has been reported by us and by others. Like SLP-76 and Blnk, Clnk was shown to act as a positive regulator of immunoreceptor signaling. Interestingly, however, it did not detectably associate with known binding partners of SLP-76, including Vav, Nck, and GADS. In contrast, it became complexed in activated T cells and myeloid cells with an as yet unknown tyrosine-phosphorylated polypeptide of approximately 92 kDa (p92). In order to understand better the function of Clnk, we sought to identify the Clnk-associated p92. Using a yeast two-hybrid screen and cotransfection experiments with Cos-1 cells, evidence was adduced that p92 is HPK-1, a serine/threonine-specific protein kinase expressed in hemopoietic cells. Further studies showed that Clnk and HPK-1 were also associated in hemopoietic cells and that their interaction was augmented by immunoreceptor stimulation. A much weaker association was detected between HPK-1 and SLP-76. Transient transfections in Jurkat T cells revealed that Clnk and HPK-1 cooperated to increase immunoreceptor-mediated activation of the interleukin 2 (IL-2) promoter. Moreover, the ability of Clnk to stimulate IL-2 promoter activity could be blocked by expression of a kinase-defective version of HPK-1. Lastly we found that in spite of the differential ability of Clnk and SLP-76 to bind cellular proteins, Clnk was apt at rescuing immunoreceptor signaling in a Jurkat T-cell variant lacking SLP-76. Taken together, these results show that Clnk physically and functionally interacts with HPK-1 in hemopoietic cells. Moreover, they suggest that Clnk is capable of functionally substituting for SLP-76 in immunoreceptor signaling, albeit by using a distinct set of intracellular effectors.
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Affiliation(s)
- J Yu
- Laboratory of Molecular Oncology, IRCM, Montréal, Québec, Canada H2W 1R7
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Tsuji S, Okamoto M, Yamada K, Okamoto N, Goitsuka R, Arnold R, Kiefer F, Kitamura D. B cell adaptor containing src homology 2 domain (BASH) links B cell receptor signaling to the activation of hematopoietic progenitor kinase 1. J Exp Med 2001; 194:529-39. [PMID: 11514608 PMCID: PMC2193495 DOI: 10.1084/jem.194.4.529] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The B cell adaptor containing src homology 2 domain (BASH; also termed BLNK or SLP-65), is crucial for B cell antigen receptor (BCR)-mediated activation, proliferation, and differentiation of B cells. BCR-mediated tyrosine-phosphorylation of BASH creates binding sites for signaling effectors such as phospholipase Cgamma (PLCgamma)2 and Vav, while the function of its COOH-terminal src homology 2 domain is unknown. We have now identified hematopoietic progenitor kinase (HPK)1, a STE20-related serine/threonine kinase, as a protein that inducibly interacts with the BASH SH2 domain. BCR ligation induced rapid tyrosine-phosphorylation of HPK1 mainly by Syk and Lyn, resulting in its association with BASH and catalytic activation. BCR-mediated activation of HPK1 was impaired in Syk- or BASH-deficient B cells. The functional SH2 domain of BASH and Tyr-379 within HPK1 which we identified as a Syk-phosphorylation site were both necessary for interaction of both proteins and efficient HPK1 activation after BCR stimulation. Furthermore, HPK1 augmented, whereas its kinase-dead mutant inhibited IkappaB kinase beta (IKKbeta) activation by BCR engagement. These results reveal a novel BCR signaling pathway leading to the activation of HPK1 and subsequently IKKbeta, in which BASH recruits tyrosine-phosphorylated HPK1 into the BCR signaling complex.
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Affiliation(s)
- Sachiyo Tsuji
- Division of Molecular Biology, Research Institute for Biological Sciences, Science University of Tokyo, Chiba 278-0022, Japan
| | - Mariko Okamoto
- Division of Molecular Biology, Research Institute for Biological Sciences, Science University of Tokyo, Chiba 278-0022, Japan
| | - Koichi Yamada
- Division of Molecular Biology, Research Institute for Biological Sciences, Science University of Tokyo, Chiba 278-0022, Japan
| | - Noriaki Okamoto
- Division of Molecular Biology, Research Institute for Biological Sciences, Science University of Tokyo, Chiba 278-0022, Japan
| | - Ryo Goitsuka
- Division of Molecular Biology, Research Institute for Biological Sciences, Science University of Tokyo, Chiba 278-0022, Japan
- Inheritance and Variation Group, PRESTO, Japan Science and Technology Corporation, Chiba 278-0022, Japan
| | - Rudiger Arnold
- Max-Planck-Institute for Physiological and Clinical Research, W.G. Kerckhoff-Institute, D-61231 Bad Nauheim, Germany
| | - Friedemann Kiefer
- Max-Planck-Institute for Physiological and Clinical Research, W.G. Kerckhoff-Institute, D-61231 Bad Nauheim, Germany
| | - Daisuke Kitamura
- Division of Molecular Biology, Research Institute for Biological Sciences, Science University of Tokyo, Chiba 278-0022, Japan
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Ling P, Meyer CF, Redmond LP, Shui JW, Davis B, Rich RR, Hu MC, Wange RL, Tan TH. Involvement of hematopoietic progenitor kinase 1 in T cell receptor signaling. J Biol Chem 2001; 276:18908-14. [PMID: 11279207 DOI: 10.1074/jbc.m101485200] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Hematopoietic progenitor kinase 1 (HPK1), a mammalian Ste20-related serine/threonine protein kinase, is a hematopoietic-specific upstream activator of the c-Jun N-terminal kinase. Here, we provide evidence to demonstrate the involvement of HPK1 in T cell receptor (TCR) signaling. HPK1 was activated and tyrosine-phosphorylated with similar kinetics following TCR/CD3 or pervanadate stimulation. Co-expression of protein-tyrosine kinases, Lck and Zap70, with HPK1 led to HPK1 activation and tyrosine phosphorylation in transfected mammalian cells. Upon TCR/CD3 stimulation, HPK1 formed inducible complexes with the adapters Nck and Crk with different kinetics, whereas it constitutively interacted with the adapters Grb2 and CrkL in Jurkat T cells. Interestingly, HPK1 also inducibly associated with linker for activation of T cells (LAT) through its proline-rich motif and translocated into glycolipid-enriched microdomains (also called lipid rafts) following TCR/CD3 stimulation, suggesting a critical role for LAT in the regulation of HPK1. Together, these results identify HPK1 as a new component of TCR signaling. T cell-specific signaling molecules Lck, Zap70, and LAT play roles in the regulation of HPK1 during TCR signaling. Differential complex formation between HPK1 and adapters highlights the possible involvement of HPK1 in multiple signaling pathways in T cells.
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Affiliation(s)
- P Ling
- Department of Immunology and the Interdepartmental Program in Cell and Molecular Biology, Baylor College of Medicine, Houston, Texas 77030, USA
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