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Kim S, Bhandari R, Brearley CA, Saiardi A. The inositol phosphate signalling network in physiology and disease. Trends Biochem Sci 2024:S0968-0004(24)00192-0. [PMID: 39317578 DOI: 10.1016/j.tibs.2024.08.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2024] [Revised: 07/29/2024] [Accepted: 08/19/2024] [Indexed: 09/26/2024]
Abstract
Combinatorial substitution of phosphate groups on the inositol ring gives rise to a plethora of inositol phosphates (InsPs) and inositol pyrophosphates (PP-InsPs). These small molecules constitute an elaborate metabolic and signalling network that influences nearly every cellular function. This review delves into the knowledge accumulated over the past decades regarding the biochemical principles and significance of InsP metabolism. We focus on the biological actions of InsPs in mammals, with an emphasis on recent findings regarding specific target proteins. We further discuss the roles of InsP metabolism in contributing to physiological homeostasis and pathological conditions. A deeper understanding of InsPs and their metabolic pathways holds the potential to address unresolved questions and propel advances towards therapeutic applications.
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Affiliation(s)
- Seyun Kim
- Department of Biological Sciences, KAIST Stem Cell Center, KAIST Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea.
| | - Rashna Bhandari
- Laboratory of Cell Signalling, Centre for DNA Fingerprinting and Diagnostics (CDFD), Inner Ring Road, Uppal, Hyderabad 500039, India.
| | - Charles A Brearley
- School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK.
| | - Adolfo Saiardi
- Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK.
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2
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Chowdhury S, Chakraborty MP, Roy S, Dey BP, Gangopadhyay K, Das R. E41K mutation activates Bruton's tyrosine kinase by stabilizing an inositol hexakisphosphate-dependent invisible dimer. J Biol Chem 2024; 300:107535. [PMID: 38971313 PMCID: PMC11338949 DOI: 10.1016/j.jbc.2024.107535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 06/19/2024] [Accepted: 06/21/2024] [Indexed: 07/08/2024] Open
Abstract
Bruton's tyrosine kinase (BTK) regulates diverse cellular signaling of the innate and adaptive immune system in response to microbial pathogens. Downregulation or constitutive activation of BTK is reported in patients with autoimmune diseases or various B-cell leukemias. BTK is a multidomain protein tyrosine kinase that adopts an Src-like autoinhibited conformation maintained by the interaction between the kinase and PH-TH domains. The PH-TH domain plays a central role in regulating BTK function. BTK is activated by binding to PIP3 at the plasma membrane upon stimulation by the B-cell receptor (BCR). The PIP3 binding allows dimerization of the PH-TH domain and subsequent transphosphorylation of the activation loop. Alternatively, a recent study shows that the multivalent T-cell-independent (TI) antigen induces BCR response by activating BTK independent of PIP3 binding. It was proposed that a transiently stable IP6-dependent PH-TH dimer may activate BTK during BCR activation by the TI antigens. However, no IP6-dependent PH-TH dimer has been identified yet. Here, we investigated a constitutively active PH-TH mutant (E41K) to determine if the elusive IP6-dependent PH-TH dimer exists. We showed that the constitutively active E41K mutation activates BTK by stabilizing the IP6-dependent PH-TH dimer. We observed that a downregulating mutation in the PH-TH domain (R28H) linked to X-linked agammaglobulinemia impairs BTK activation at the membrane and in the cytosol by preventing PH-TH dimerization. We conclude that the IP6 dynamically remodels the BTK active fraction between the membrane and the cytoplasm. Stimulating with IP6 increases the cytosolic fraction of the activated BTK.
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Affiliation(s)
- Subhankar Chowdhury
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, India
| | - Manas Pratim Chakraborty
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, India
| | - Swarnendu Roy
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, India
| | - Bipra Prasad Dey
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, India
| | - Kaustav Gangopadhyay
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, India
| | - Rahul Das
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur, India; Centre for Advanced Functional Materials, Indian Institute of Science Education and Research Kolkata, Mohanpur, India.
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Jin Y, Yuan H, Mehta I, Ezenwa O, Morel PA. Alternatively Spliced Variants of Murine CD247 Influence T Cell Development and Activation, Revealing the Importance of the CD3ζ C-Terminal Region. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2024; 212:541-550. [PMID: 38117282 PMCID: PMC10872740 DOI: 10.4049/jimmunol.2300511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 11/28/2023] [Indexed: 12/21/2023]
Abstract
CD247, also known as CD3ζ, is a crucial signaling molecule that transduces signals delivered by TCR through its three ITAMs. CD3ζ is required for successful thymocyte development. Three additional alternatively spliced variants of murine CD247 have been described, that is, CD3ι, CD3θ, and CD3η, that differ from CD3ζ in the C terminus such that the third ITAM is lost. Previous studies demonstrated defects in T cell development in mice expressing CD3η, but the TCR signaling pathways affected by CD3η and the impacts of the CD3ι and CD3θ on T cell development were not explored. In this study, we used a retrovirus-mediated gene transfer technique to express these three isoforms individually and examined the roles of them on T cell development and activation. Rag1-/- mice reconstituted with CD3θ-expressing bone marrow failed to develop mature T cells. CD3ι-expressing T cells exhibited similar development and activation as cells expressing CD3ζ. In contrast, thymic development was severely impaired in CD3η-reconstituted mice. Single-positive but not double-positive CD3η-expressing thymocytes had reduced TCR expression, and CD5 expression was decreased at the double-positive stage, suggesting a defect in positive selection. Peripheral CD3η-expressing T cells had expanded CD44hi populations and upregulation of exhaustion markers seen by flow cytometry and RNA sequencing analysis. Analysis of early signaling events demonstrated significantly reduced activation of both the PLCγ1 and Akt/mTOR signaling pathways. There was also a reduction in the frequency of activation of CD3η-expressing T cells. These studies reveal the importance of the CD3ζ C-terminal region in T cell development and activation.
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Affiliation(s)
- Ye Jin
- Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Huijuan Yuan
- Department of Medicine, University of Pittsburgh School of Medicine, Pittsburgh PA
| | - Isha Mehta
- Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Ogechukwu Ezenwa
- Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA
| | - Penelope A Morel
- Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA
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4
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Kumar P, Rajasekaran K, Malarkannan S. Novel PI(3)K-p85α/p110δ-ITK-LAT-PLC-γ2 and Fyn-ADAP-Carma1-TAK1 Pathways Define Reverse Signaling via FasL. Crit Rev Immunol 2024; 44:55-77. [PMID: 37947072 DOI: 10.1615/critrevimmunol.2023049638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2023]
Abstract
The role of FasL in initiating death signals through Fas is well characterized. However, the reverse signaling pathway downstream of FasL in effector lymphocytes is poorly understood. Here, we identify that FasL functions as an independent activation receptor in NK cells. Activation via FasL results in the production of LFN-γ, GM-CSF, RANTES, MIP-1α, and MIP1-β. Proximal signaling of FasL requires Lck and Fyn. Upon activation, FasL facilitates the phosphorylation of PI(3)K-p85α/p55α subunits. A catalytically inactive PI(3)K-p110δD910A mutation significantly impairs the cytokine and chemokine production by FasL. Activation of ITK and LAT downstream of FasL plays a central role in recruiting and phosphorylating PLC-γ2. Importantly, Fyn-mediated recruitment of ADAP links FasL to the Carmal/ Bcl10/Tak1 signalosome. Lack of Carma1, CARD domain of Carma1, or Tak1 significantly reduces FasL-mediated cytokine and chemokine production. These findings, for the first time, provide a detailed molecular blueprint that defines FasL-mediated reverse signaling.
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Affiliation(s)
- Pawan Kumar
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, NY 11794
| | | | - Subramaniam Malarkannan
- Laboratory of Molecular Immunology and Immunotherapy, Blood Research Institute, Milwaukee, WI 53226; Departments of Pediatrics and Medicine, Medical College of Wisconsin, Milwaukee, WI 53226
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Authi KS, Khan S, Gibbins JM, Brain SD. Evidence that inositol 1,4,5-trisphosphate 3-kinase and inositol 1,3,4,5-tetrakisphosphate are negative regulators of platelet function. Res Pract Thromb Haemost 2024; 8:102326. [PMID: 38404940 PMCID: PMC10885593 DOI: 10.1016/j.rpth.2024.102326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 12/21/2023] [Accepted: 01/03/2024] [Indexed: 02/27/2024] Open
Abstract
Background Inositol 1,3,4,5-tetrakisphosphate (IP4) is formed from inositol 1,4,5-trisphosphate (IP3) by IP3 3-kinase (ITPK) in most cells. Its function is unknown but has been suggested to be involved in Ca2+ entry, IP3 regulation, and phosphoinositide 3-kinase antagonism. Objectives To better elucidate a function for IP4, we tested a specific inhibitor of ITPK (GNF362) on platelets, the effects of IP4 directly in permeabilized platelets and its effect on phosphatidylinositol 3,4,5-trisphosphate (PIP3) binding to pleckstrin-homology (PH) domain-containing proteins in platelets. Methods Human platelets were utilized in whole blood for thrombus formation, in platelet-rich plasma and washed suspensions for aggregation, and for Ca2+ studies, or resuspended in high K+ and low Na+ buffers for permeabilization experiments. Phosphorylation of AKT-Ser473 and Rap1-GTP formation were measured by Western blotting and PIP3 binding using PIP3 beads. Results GNF362-enhanced platelet aggregation stimulated by low concentrations of ADP, collagen, thrombin, U46619, and thrombus formation in collagen-coated capillaries. GNF362 induced a transient elevation of Ca2+ concentration, elevated basal levels of IP3, and enhanced the peak height of Ca2+ elevated by agonists. In permeabilized platelets, IP4 inhibited GTPγS induced formation of AKT-Ser473 phosphorylation and platelet aggregation. IP4 reduced GTPγS-stimulated Rap1-GTP levels and potently reduced extraction of RASA3 and BTK by PIP3 beads. Conclusion ITPK and IP4 are negative regulators of platelet function. IP4 regulation of PH domain-containing proteins may represent a pathway by which platelet activation may be controlled during thrombosis.
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Affiliation(s)
- Kalwant S. Authi
- School of Cardiovascular and Metabolic Medicine and Sciences, BHF Centre for Research Excellence, London, UK
| | - Sabeeya Khan
- Institute for Cardiovascular and Metabolic Research, School of Biological Sciences, University of Reading, Reading, UK
| | - Jonathan M. Gibbins
- Institute for Cardiovascular and Metabolic Research, School of Biological Sciences, University of Reading, Reading, UK
| | - Susan D. Brain
- School of Cardiovascular and Metabolic Medicine and Sciences, BHF Centre for Research Excellence, London, UK
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Preiss NK, Kamal Y, Wilkins OM, Li C, Kolling FW, Trask HW, Usherwood YK, Cheng C, Frost HR, Usherwood EJ. Characterizing control of memory CD8 T cell differentiation by BTB-ZF transcription factor Zbtb20. Life Sci Alliance 2023; 6:e202201683. [PMID: 37414528 PMCID: PMC10326419 DOI: 10.26508/lsa.202201683] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 06/14/2023] [Accepted: 06/15/2023] [Indexed: 07/08/2023] Open
Abstract
Members of the BTB-ZF transcription factor family regulate the immune system. Our laboratory identified that family member Zbtb20 contributes to the differentiation, recall responses, and metabolism of CD8 T cells. Here, we report a characterization of the transcriptional and epigenetic signatures controlled by Zbtb20 at single-cell resolution during the effector and memory phases of the CD8 T cell response. Without Zbtb20, transcriptional programs associated with memory CD8 T cell formation were up-regulated throughout the CD8 T response. A signature of open chromatin was associated with genes controlling T cell activation, consistent with the known impact on differentiation. In addition, memory CD8 T cells lacking Zbtb20 were characterized by open chromatin regions with overrepresentation of AP-1 transcription factor motifs and elevated RNA- and protein-level expressions of the corresponding AP-1 components. Finally, we describe motifs and genomic annotations from the DNA targets of Zbtb20 in CD8 T cells identified by cleavage under targets and release under nuclease (CUT&RUN). Together, these data establish the transcriptional and epigenetic networks contributing to the control of CD8 T cell responses by Zbtb20.
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Affiliation(s)
- Nicholas K Preiss
- Microbiology and Immunology Department, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA
| | - Yasmin Kamal
- Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Owen M Wilkins
- Department of Biomedical Data Science, Geisel School of Medicine, Dartmouth College, Hanover, NH, USA
- Genomics and Molecular Biology Shared Resource, Dartmouth Cancer Center, Geisel School of Medicine, Lebanon, NH, USA
| | - Chenyang Li
- Genomic Medicine Department, University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Graduate School of Biomedical Sciences, The University of Texas MD Anderson Cancer Center UTHealth Houston, Houston, TX, USA
| | - Fred W Kolling
- Genomics and Molecular Biology Shared Resource, Dartmouth Cancer Center, Geisel School of Medicine, Lebanon, NH, USA
| | - Heidi W Trask
- Genomics and Molecular Biology Shared Resource, Dartmouth Cancer Center, Geisel School of Medicine, Lebanon, NH, USA
| | - Young-Kwang Usherwood
- Microbiology and Immunology Department, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA
| | - Chao Cheng
- Department of Medicine, Baylor College of Medicine, Houston, TX, USA
- Dan L Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, TX, USA
- The Institute for Clinical and Translational Research, Baylor College of Medicine, Houston, TX, USA
| | - Hildreth R Frost
- Department of Biomedical Data Science, Geisel School of Medicine, Dartmouth College, Hanover, NH, USA
| | - Edward J Usherwood
- Microbiology and Immunology Department, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA
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Liang W, Li K, Zhang Q, Li K, Ai K, Zhang J, Jiao X, Li J, Wei X, Yang J. Interleukin-2 inducible T cell kinase (ITK) may participate in the anti-bacterial immune response of Nile tilapia via regulating T-cell activation. FISH & SHELLFISH IMMUNOLOGY 2022; 127:419-426. [PMID: 35779809 DOI: 10.1016/j.fsi.2022.06.044] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 05/28/2022] [Accepted: 06/24/2022] [Indexed: 06/15/2023]
Abstract
Interleukin-2 inducible T cell kinase (ITK) plays a predominant role in the T-cell receptor (TCR) signaling cascade to ensure valid T-cell activation and function. Nevertheless, whether it regulates T-cell response of early vertebrates remains unknown. Herein, we investigated the involvement of ITK in the lymphocyte-mediated adaptive immune response, and its regulation to T-cell activation in the Nile tilapia Oreochromis niloticus. Both sequence and structure of O. niloticus ITK (OnITK) were remarkably conserved with its homologues from other vertebrates, implying its potential conserved function. OnITK mRNA was extensively expressed in lymphoid-related tissues, and with the relative highest level in peripheral blood. Once Nile tilapia was infected by Edwardsiella piscicida, OnITK in splenic lymphocytes was significantly up-regulated on 7-day post infection at both transcription and translation levels, suggesting that OnITK might involve in the primary adaptive immune response of teleost. Furthermore, upon splenic lymphocytes were stimulated by T-cell specific mitogen PHA, OnITK mRNA and protein levels were dramatically elevated. More importantly, treatment of splenic lymphocytes with specific inhibitor significantly crippled OnITK expression, which in turn impaired the inducible expression of T-cell activation markers IFN-γ, IL-2 and CD122, indicating the critical roles of ITK in regulating T-cell activation of Nile tilapia. Taken together, our results suggest that ITK takes part in the lymphocyte-mediated adaptive immunity of tilapia, and is indispensable for T-cell activation of teleost. Our findings thus provide novel evidences for understanding the mechanism regulating T-cell immunity of early vertebrates, as well as the evolution of adaptive immune system.
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Affiliation(s)
- Wei Liang
- State Key Laboratory of Estuarine and Coastal Research, School of Life Sciences, East China Normal University, Shanghai, 200241, China
| | - Kunming Li
- State Key Laboratory of Estuarine and Coastal Research, School of Life Sciences, East China Normal University, Shanghai, 200241, China
| | - Qian Zhang
- State Key Laboratory of Estuarine and Coastal Research, School of Life Sciences, East China Normal University, Shanghai, 200241, China
| | - Kang Li
- State Key Laboratory of Estuarine and Coastal Research, School of Life Sciences, East China Normal University, Shanghai, 200241, China
| | - Kete Ai
- State Key Laboratory of Estuarine and Coastal Research, School of Life Sciences, East China Normal University, Shanghai, 200241, China
| | - Jiansong Zhang
- State Key Laboratory of Estuarine and Coastal Research, School of Life Sciences, East China Normal University, Shanghai, 200241, China
| | - Xinying Jiao
- State Key Laboratory of Estuarine and Coastal Research, School of Life Sciences, East China Normal University, Shanghai, 200241, China
| | - Jiaqi Li
- State Key Laboratory of Estuarine and Coastal Research, School of Life Sciences, East China Normal University, Shanghai, 200241, China
| | - Xiumei Wei
- State Key Laboratory of Estuarine and Coastal Research, School of Life Sciences, East China Normal University, Shanghai, 200241, China.
| | - Jialong Yang
- State Key Laboratory of Estuarine and Coastal Research, School of Life Sciences, East China Normal University, Shanghai, 200241, China; Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China
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Gangopadhyay K, Roy S, Sen Gupta S, Chandradasan A, Chowdhury S, Das R. Regulating the discriminatory response to antigen by T-cell receptor. Biosci Rep 2022; 42:BSR20212012. [PMID: 35260878 PMCID: PMC8965820 DOI: 10.1042/bsr20212012] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 03/04/2022] [Accepted: 03/08/2022] [Indexed: 11/17/2022] Open
Abstract
The cell-mediated immune response constitutes a robust host defense mechanism to eliminate pathogens and oncogenic cells. T cells play a central role in such a defense mechanism and creating memories to prevent any potential infection. T cell recognizes foreign antigen by its surface receptors when presented through antigen-presenting cells (APCs) and calibrates its cellular response by a network of intracellular signaling events. Activation of T-cell receptor (TCR) leads to changes in gene expression and metabolic networks regulating cell development, proliferation, and migration. TCR does not possess any catalytic activity, and the signaling initiates with the colocalization of several enzymes and scaffold proteins. Deregulation of T cell signaling is often linked to autoimmune disorders like severe combined immunodeficiency (SCID), rheumatoid arthritis, and multiple sclerosis. The TCR remarkably distinguishes the minor difference between self and non-self antigen through a kinetic proofreading mechanism. The output of TCR signaling is determined by the half-life of the receptor antigen complex and the time taken to recruit and activate the downstream enzymes. A longer half-life of a non-self antigen receptor complex could initiate downstream signaling by activating associated enzymes. Whereas, the short-lived, self-peptide receptor complex disassembles before the downstream enzymes are activated. Activation of TCR rewires the cellular metabolic response to aerobic glycolysis from oxidative phosphorylation. How does the early event in the TCR signaling cross-talk with the cellular metabolism is an open question. In this review, we have discussed the recent developments in understanding the regulation of TCR signaling, and then we reviewed the emerging role of metabolism in regulating T cell function.
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Affiliation(s)
- Kaustav Gangopadhyay
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur campus, Mohanpur 741246, India
| | - Swarnendu Roy
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur campus, Mohanpur 741246, India
| | - Soumee Sen Gupta
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur campus, Mohanpur 741246, India
| | - Athira C. Chandradasan
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur campus, Mohanpur 741246, India
| | - Subhankar Chowdhury
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur campus, Mohanpur 741246, India
| | - Rahul Das
- Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur campus, Mohanpur 741246, India
- Centre for Advanced Functional Materials, Indian Institute of Science Education and Research Kolkata, Mohanpur campus, Mohanpur 741246, India
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Lowe J, Joseph RE, Andreotti AH. Conformational switches that control the TEC kinase – PLCγ signaling axis. J Struct Biol X 2022; 6:100061. [PMID: 35128378 PMCID: PMC8803661 DOI: 10.1016/j.yjsbx.2022.100061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 01/15/2022] [Accepted: 01/18/2022] [Indexed: 11/27/2022] Open
Abstract
TEC kinases and PLCγ transition between autoinhibited state and active conformation. PLCγ structures reveal both autoinhibited form and active form of gamma specific array (γSA); the four regulatory domains unique to the PLCγ isozymes. Domain dynamics likely control activation mechanism. PLCγ phosphorylation triggers conformational switch.
Cell surface receptors such as the T-cell receptor (TCR) and B-cell receptor (BCR) engage with external stimuli to transmit information into the cell and initiate a cascade of signaling events that lead to gene expression that drives the immune response. At the heart of controlling T- and B-cell cell signaling, phospholipase Cγ hydrolyzes membrane associated PIP2, leading to generation of the second messengers IP3 and DAG. These small molecules trigger mobilization of intracellular Ca2+ and promote transcription factor transport into the nucleus launching the adaptive immune response. The TEC family kinases are responsible for phosphorylating and activating PLCγ, and our group aims to understand mechanisms that regulate immune cell signal transduction by focusing on this kinase/phospholipase axis in T-cells and B-cells. Here, we review the current molecular level understanding of how the TEC kinases (ITK and BTK) and PLCγ1/2 are autoinhibited prior to activation of cell surface receptors, how TEC kinases are activated to specifically recognize the PLCγ substrate, and how conformational changes induced by phosphorylation trigger PLCγ activation.
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10
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Johansen KH, Golec DP, Thomsen JH, Schwartzberg PL, Okkenhaug K. PI3K in T Cell Adhesion and Trafficking. Front Immunol 2021; 12:708908. [PMID: 34421914 PMCID: PMC8377255 DOI: 10.3389/fimmu.2021.708908] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 07/19/2021] [Indexed: 12/12/2022] Open
Abstract
PI3K signalling is required for activation, differentiation, and trafficking of T cells. PI3Kδ, the dominant PI3K isoform in T cells, has been extensively characterised using PI3Kδ mutant mouse models and PI3K inhibitors. Furthermore, characterisation of patients with Activated PI3K Delta Syndrome (APDS) and mouse models with hyperactive PI3Kδ have shed light on how increased PI3Kδ activity affects T cell functions. An important function of PI3Kδ is that it acts downstream of TCR stimulation to activate the major T cell integrin, LFA-1, which controls transendothelial migration of T cells as well as their interaction with antigen-presenting cells. PI3Kδ also suppresses the cell surface expression of CD62L and CCR7 which controls the migration of T cells across high endothelial venules in the lymph nodes and S1PR1 which controls lymph node egress. Therefore, PI3Kδ can control both entry and exit of T cells from lymph nodes as well as the recruitment to and retention of T cells within inflamed tissues. This review will focus on the regulation of adhesion receptors by PI3Kδ and how this contributes to T cell trafficking and localisation. These findings are relevant for our understanding of how PI3Kδ inhibitors may affect T cell redistribution and function.
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Affiliation(s)
- Kristoffer H Johansen
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom.,Laboratory of Immune System Biology, NIAID, NIH, Bethesda, MD, United States
| | - Dominic P Golec
- Laboratory of Immune System Biology, NIAID, NIH, Bethesda, MD, United States
| | - Julie H Thomsen
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
| | | | - Klaus Okkenhaug
- Department of Pathology, University of Cambridge, Cambridge, United Kingdom
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11
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Preiss NK, Kang T, Usherwood YK, Huang YH, Branchini BR, Usherwood EJ. Control of B Cell Lymphoma by Gammaherpesvirus-Induced Memory CD8 T Cells. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2020; 205:3372-3382. [PMID: 33188072 PMCID: PMC7924667 DOI: 10.4049/jimmunol.2000734] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 10/13/2020] [Indexed: 02/02/2023]
Abstract
Persistent infection with gammaherpesviruses (γHV) can cause lymphomagenesis in immunocompromised patients. Murine γHV-68 (MHV-68) is an important tool for understanding immune factors contributing to γHV control; however, modeling control of γHV-associated lymphomagenesis has been challenging. Current model systems require very long incubation times or severe immune suppression, and tumor penetrance is low. In this report, we describe the generation of a B cell lymphoma on the C57BL/6 background, which is driven by the Myc oncogene and expresses an immunodominant CD8 T cell epitope from MHV-68. We determined MHV-68-specific CD8 T cells in latently infected mice use either IFN-γ or perforin/granzyme to control γHV-associated lymphoma, but perforin/granzyme is a more potent effector mechanism for lymphoma control than IFN-γ. Consistent with previous reports, CD4-depleted mice lost control of virus replication in persistently infected mice. However, control of lymphoma remained intact in the absence of CD4 T cells. Collectively, these data show the mechanisms of T cell control of B cell lymphoma in γHV-infected mice overlap with those necessary for control of virus replication, but there are also important differences. This study establishes a tool for further dissecting immune surveillance against, and optimizing adoptive T cell therapies for, γHV-associated lymphomas.
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Affiliation(s)
- Nicholas K Preiss
- Microbiology and Immunology Department, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756; and
| | - Taewook Kang
- Microbiology and Immunology Department, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756; and
| | - Young-Kwang Usherwood
- Microbiology and Immunology Department, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756; and
| | - Yina H Huang
- Microbiology and Immunology Department, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756; and
| | | | - Edward J Usherwood
- Microbiology and Immunology Department, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756; and
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12
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Lechner KS, Neurath MF, Weigmann B. Role of the IL-2 inducible tyrosine kinase ITK and its inhibitors in disease pathogenesis. J Mol Med (Berl) 2020; 98:1385-1395. [PMID: 32808093 PMCID: PMC7524833 DOI: 10.1007/s00109-020-01958-z] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 07/10/2020] [Accepted: 08/04/2020] [Indexed: 01/18/2023]
Abstract
ITK (IL-2-inducible tyrosine kinase) belongs to the Tec family kinases and is mainly expressed in T cells. It is involved in TCR signalling events driving processes like T cell development as well as Th2, Th9 and Th17 responses thereby controlling the expression of pro-inflammatory cytokines. Studies have shown that ITK is involved in the pathogenesis of autoimmune diseases as well as in carcinogenesis. The loss of ITK or its activity either by mutation or by the use of inhibitors led to a beneficial outcome in experimental models of asthma, inflammatory bowel disease and multiple sclerosis among others. In humans, biallelic mutations in the ITK gene locus result in a monogenetic disorder leading to T cell dysfunction; in consequence, mainly EBV infections can lead to severe immune dysregulation evident by lymphoproliferation, lymphoma and hemophagocytic lymphohistiocytosis. Furthermore, patients who suffer from angioimmunoblastic T cell lymphoma have been found to express significantly more ITK. These findings put ITK in the strong focus as a target for drug development.
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Affiliation(s)
- Kristina S Lechner
- Department of Medicine 1, Kussmaul Campus for Medical Research, University of Erlangen-Nürnberg, Hartmannstr.14, 91052, Erlangen, Germany
| | - Markus F Neurath
- Department of Medicine 1, Kussmaul Campus for Medical Research, University of Erlangen-Nürnberg, Hartmannstr.14, 91052, Erlangen, Germany
- Deutsches Zentrum Immuntherapie (DZI), Ulmenweg 18, 91054, Erlangen, Germany
- Ludwig Demling Endoscopy Center of Excellence, Ulmenweg 18, 91054, Erlangen, Germany
| | - Benno Weigmann
- Department of Medicine 1, Kussmaul Campus for Medical Research, University of Erlangen-Nürnberg, Hartmannstr.14, 91052, Erlangen, Germany.
- Medical Immunology Campus Erlangen, Medical Clinic 1, Friedrich-Alexander University Erlangen-Nürnberg, 91052, Erlangen, Germany.
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13
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Contrepois K, Wu S, Moneghetti KJ, Hornburg D, Ahadi S, Tsai MS, Metwally AA, Wei E, Lee-McMullen B, Quijada JV, Chen S, Christle JW, Ellenberger M, Balliu B, Taylor S, Durrant MG, Knowles DA, Choudhry H, Ashland M, Bahmani A, Enslen B, Amsallem M, Kobayashi Y, Avina M, Perelman D, Schüssler-Fiorenza Rose SM, Zhou W, Ashley EA, Montgomery SB, Chaib H, Haddad F, Snyder MP. Molecular Choreography of Acute Exercise. Cell 2020; 181:1112-1130.e16. [PMID: 32470399 PMCID: PMC7299174 DOI: 10.1016/j.cell.2020.04.043] [Citation(s) in RCA: 234] [Impact Index Per Article: 58.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 12/10/2019] [Accepted: 04/21/2020] [Indexed: 02/07/2023]
Abstract
Acute physical activity leads to several changes in metabolic, cardiovascular, and immune pathways. Although studies have examined selected changes in these pathways, the system-wide molecular response to an acute bout of exercise has not been fully characterized. We performed longitudinal multi-omic profiling of plasma and peripheral blood mononuclear cells including metabolome, lipidome, immunome, proteome, and transcriptome from 36 well-characterized volunteers, before and after a controlled bout of symptom-limited exercise. Time-series analysis revealed thousands of molecular changes and an orchestrated choreography of biological processes involving energy metabolism, oxidative stress, inflammation, tissue repair, and growth factor response, as well as regulatory pathways. Most of these processes were dampened and some were reversed in insulin-resistant participants. Finally, we discovered biological pathways involved in cardiopulmonary exercise response and developed prediction models revealing potential resting blood-based biomarkers of peak oxygen consumption.
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Affiliation(s)
- Kévin Contrepois
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA; Stanford Cardiovascular Institute, Stanford University, Stanford, CA, USA
| | - Si Wu
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Kegan J Moneghetti
- Stanford Cardiovascular Institute, Stanford University, Stanford, CA, USA; Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford, CA, USA; Department of Medicine, St. Vincent's Hospital, University of Melbourne, Melbourne, VIC, Australia; Stanford Sports Cardiology, Department of Medicine, Stanford University, Stanford, CA, USA
| | - Daniel Hornburg
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Sara Ahadi
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Ming-Shian Tsai
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Ahmed A Metwally
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Eric Wei
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | | | - Jeniffer V Quijada
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Songjie Chen
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Jeffrey W Christle
- Stanford Cardiovascular Institute, Stanford University, Stanford, CA, USA; Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford, CA, USA; Stanford Sports Cardiology, Department of Medicine, Stanford University, Stanford, CA, USA
| | - Mathew Ellenberger
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Brunilda Balliu
- Department of Pathology, Stanford University, Stanford, CA, USA
| | - Shalina Taylor
- Pediatrics Department, Stanford University School of Medicine, Stanford, CA, USA
| | - Matthew G Durrant
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - David A Knowles
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA; Department of Radiology, Stanford University, Stanford, CA, USA
| | - Hani Choudhry
- Department of Biochemistry, Faculty of Science, Cancer and Mutagenesis Unit, King Fahd Center for Medical Research, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Melanie Ashland
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Amir Bahmani
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Brooke Enslen
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Myriam Amsallem
- Stanford Cardiovascular Institute, Stanford University, Stanford, CA, USA; Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Yukari Kobayashi
- Stanford Cardiovascular Institute, Stanford University, Stanford, CA, USA; Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Monika Avina
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Dalia Perelman
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | | | - Wenyu Zhou
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Euan A Ashley
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA; Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford, CA, USA; Center for Undiagnosed Diseases, Stanford University, Stanford, CA, USA
| | - Stephen B Montgomery
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA; Department of Pathology, Stanford University, Stanford, CA, USA
| | - Hassan Chaib
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Francois Haddad
- Stanford Cardiovascular Institute, Stanford University, Stanford, CA, USA; Division of Cardiovascular Medicine, Stanford University School of Medicine, Stanford, CA, USA; Stanford Diabetes Research Center, Stanford University, Stanford, CA, USA.
| | - Michael P Snyder
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA; Stanford Cardiovascular Institute, Stanford University, Stanford, CA, USA; Stanford Diabetes Research Center, Stanford University, Stanford, CA, USA.
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14
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Andreotti AH, Joseph RE, Conley JM, Iwasa J, Berg LJ. Multidomain Control Over TEC Kinase Activation State Tunes the T Cell Response. Annu Rev Immunol 2019; 36:549-578. [PMID: 29677469 DOI: 10.1146/annurev-immunol-042617-053344] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Signaling through the T cell antigen receptor (TCR) activates a series of tyrosine kinases. Directly associated with the TCR, the SRC family kinase LCK and the SYK family kinase ZAP-70 are essential for all downstream responses to TCR stimulation. In contrast, the TEC family kinase ITK is not an obligate component of the TCR cascade. Instead, ITK functions as a tuning dial, to translate variations in TCR signal strength into differential programs of gene expression. Recent insights into TEC kinase structure have provided a view into the molecular mechanisms that generate different states of kinase activation. In resting lymphocytes, TEC kinases are autoinhibited, and multiple interactions between the regulatory and kinase domains maintain low activity. Following TCR stimulation, newly generated signaling modules compete with the autoinhibited core and shift the conformational ensemble to the fully active kinase. This multidomain control over kinase activation state provides a structural mechanism to account for ITK's ability to tune the TCR signal.
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Affiliation(s)
- Amy H Andreotti
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa 50011, USA; ,
| | - Raji E Joseph
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa 50011, USA; ,
| | - James M Conley
- Department of Pathology, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA; ,
| | - Janet Iwasa
- Department of Biochemistry, University of Utah, Salt Lake City, Utah 84112, USA;
| | - Leslie J Berg
- Department of Pathology, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA; ,
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15
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Kim W, Kim E, Min H, Kim MG, Eisenbeis VB, Dutta AK, Pavlovic I, Jessen HJ, Kim S, Seong RH. Inositol polyphosphates promote T cell-independent humoral immunity via the regulation of Bruton's tyrosine kinase. Proc Natl Acad Sci U S A 2019; 116:12952-12957. [PMID: 31189594 PMCID: PMC6600927 DOI: 10.1073/pnas.1821552116] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
T cell-independent (TI) B cell response is critical for the early protection against pathogen invasion. The regulation and activation of Bruton's tyrosine kinase (Btk) is known as a pivotal step of B cell antigen receptor (BCR) signaling in TI humoral immunity, as observed in patients with X-linked agammaglobulinemia (XLA) experiencing a high incidence of encapsulated bacterial infections. However, key questions remain as to whether a well-established canonical BCR signaling pathway is sufficient to regulate the activity of Btk. Here, we find that inositol hexakisphosphate (InsP6) acts as a physiological regulator of Btk in BCR signaling. Absence of higher order inositol phosphates (InsPs), inositol polyphosphates, leads to an inability to mount immune response against TI antigens. Interestingly, the significance of InsP6-mediated Btk regulation is more prominent in IgM+ plasma cells. Hence, the present study identifies higher order InsPs as principal components of B cell activation upon TI antigen stimulation and presents a mechanism for InsP-mediated regulation of the BCR signaling.
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MESH Headings
- Agammaglobulinaemia Tyrosine Kinase/immunology
- Agammaglobulinaemia Tyrosine Kinase/metabolism
- Agammaglobulinemia/genetics
- Agammaglobulinemia/immunology
- Agammaglobulinemia/pathology
- Animals
- B-Lymphocytes/immunology
- B-Lymphocytes/metabolism
- Disease Models, Animal
- Genetic Diseases, X-Linked/genetics
- Genetic Diseases, X-Linked/immunology
- Genetic Diseases, X-Linked/pathology
- Humans
- Immunity, Humoral
- Mice
- Mice, Transgenic
- Phosphotransferases (Alcohol Group Acceptor)/genetics
- Phosphotransferases (Alcohol Group Acceptor)/metabolism
- Phytic Acid/immunology
- Phytic Acid/metabolism
- Receptors, Antigen, B-Cell/immunology
- Receptors, Antigen, B-Cell/metabolism
- Signal Transduction/immunology
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Affiliation(s)
- Wooseob Kim
- School of Biological Sciences and Institute of Molecular Biology and Genetics, Seoul National University, 08826 Seoul, Korea
| | - Eunha Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 34141 Daejeon, Korea
| | - Hyungyu Min
- School of Biological Sciences and Institute of Molecular Biology and Genetics, Seoul National University, 08826 Seoul, Korea
| | - Min Gyu Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 34141 Daejeon, Korea
| | - Verena B Eisenbeis
- Institute of Organic Chemistry, University of Freiburg, 79104 Freiburg, Germany
| | - Amit K Dutta
- Institute of Organic Chemistry, University of Freiburg, 79104 Freiburg, Germany
| | - Igor Pavlovic
- Department of Chemistry, Technical University Munich, D-85748 Garching, Germany
| | - Henning J Jessen
- Institute of Organic Chemistry, University of Freiburg, 79104 Freiburg, Germany
- Centre for Integrative Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany
| | - Seyun Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 34141 Daejeon, Korea;
| | - Rho Hyun Seong
- School of Biological Sciences and Institute of Molecular Biology and Genetics, Seoul National University, 08826 Seoul, Korea;
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16
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Gawden-Bone CM, Griffiths GM. Phospholipids: Pulling Back the Actin Curtain for Granule Delivery to the Immune Synapse. Front Immunol 2019; 10:700. [PMID: 31031745 PMCID: PMC6470250 DOI: 10.3389/fimmu.2019.00700] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Accepted: 03/14/2019] [Indexed: 12/29/2022] Open
Abstract
Phosphoinositides, together with the phospholipids phosphatidylserine and phosphatidic acid, are important components of the plasma membrane acting as second messengers that, with diacylglycerol, regulate a diverse range of signaling events converting extracellular changes into cellular responses. Local changes in their distribution and membrane charge on the inner leaflet of the plasma membrane play important roles in immune cell function. Here we discuss their distribution and regulators highlighting the importance of membrane changes across the immune synapse on the cytoskeleton and the impact on the function of cytotoxic T lymphocytes.
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Affiliation(s)
| | - Gillian M Griffiths
- Cambridge Institute of Medical Research, University of Cambridge, Cambridge, United Kingdom
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17
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Cruz-Muñoz ME, Valenzuela-Vázquez L, Sánchez-Herrera J, Santa-Olalla Tapia J. From the "missing self" hypothesis to adaptive NK cells: Insights of NK cell-mediated effector functions in immune surveillance. J Leukoc Biol 2019; 105:955-971. [PMID: 30848847 DOI: 10.1002/jlb.mr0618-224rr] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 01/29/2019] [Accepted: 02/04/2019] [Indexed: 12/11/2022] Open
Abstract
The original discovery of NK cells approximately 40 yr ago was based on their unique capability to kill tumor cells without prior sensitization or priming, a process named natural cytotoxicity. Since then, several studies have documented that NK cells can kill hematopoietic and nonhematopoietic cancer cells. NK cells also recognize and kill cells that have undergone viral infections. Besides natural cytotoxicity, NK cells are also major effectors of antibody-dependent cell cytotoxicity (ADCC). Therefore, NK cells are well "armed" to recognize and mount immune responses against "insults" that result from cell transformation and viral infections. Because of these attributes, an essential role of NK cells in tumor surveillance was noted. Indeed, several studies have shown a correlation between impaired NK cell cytotoxicity and a higher risk of developing cancer. This evidence led to the idea that cancer initiation and progress is intimately related to an abnormal or misdirected immune response. Whereas all these ideas remain current, it is also true that NK cells represent a heterogeneous population with different abilities to secrete cytokines and to mediate cytotoxic functions. In addition, recent data has shown that NK cells are prone to suffer epigenetic modifications resulting in the acquisition of previously unrecognized attributes such as memory and long-term survival. Such NK cells, referred as "adaptive" or "memory-like," also display effector functions that are not necessarily equal to those observed in conventional NK cells. Given the new evidence available, it is essential to discuss the conceptual reasoning and misconceptions regarding the role of NK cells in immune surveillance and immunotherapy.
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18
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Effect of the actin- and calcium-regulating activities of ITPKB on the metastatic potential of lung cancer cells. Biochem J 2018; 475:2057-2071. [DOI: 10.1042/bcj20180238] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 06/01/2018] [Accepted: 06/05/2018] [Indexed: 01/10/2023]
Abstract
Inositol-1,4,5-trisphosphate 3-kinase-A (ITPKA) exhibits oncogenic activity in lung cancer cells by regulating Ins(1,4,5)P3-mediated calcium release and cytoskeletal dynamics. Since, in normal cells, ITPKA is mainly expressed in the brain, it is an excellent target for selected therapy of lung cancer. However, ITPKB is strongly expressed in normal lung tissues, but is down-regulated in lung cancer cells by miR-375, assuming that ITPKB might have tumor suppressor activity. In addition, ITPKB binds to F-actin making it likely that, similar to ITPKA, it controls actin dynamics. Thus, the treatment of ITPKA-expressing lung cancer with ITPKA inhibitors simultaneously inhibiting ITPKB may counteract the therapy. Based on these considerations, we analyzed if ITPKB controls actin dynamics and if the protein reduces aggressive progression of lung cancer cells. We found that ITPKB bundled F-actin in cell-free systems. However, the stable expression of ITPKB in H1299 lung cancer cells, exhibiting very low endogenous ITPKB expression, had no significant effect on the actin structure. In addition, our data show that ITPKB negatively controls transmigration of H1299 cells in vitro by blocking Ins(1,4,5)P3-mediated calcium release. On the other hand, colony formation was stimulated by ITPKB, independent of Ins(1,4,5)P3-mediated calcium signals. However, dissemination of H1299 cells from the skin to the lung in NOD scid gamma mice was not significantly affected by ITPKB expression. In summary, ITPKB does not affect the cellular actin structure and does not suppress dissemination of human lung cancer cells in mice. Thus, our initial hypotheses that ITPKB exhibits tumor suppressor activity could not be supported.
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19
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Elich M, Sauer K. Regulation of Hematopoietic Cell Development and Function Through Phosphoinositides. Front Immunol 2018; 9:931. [PMID: 29780388 PMCID: PMC5945867 DOI: 10.3389/fimmu.2018.00931] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 04/16/2018] [Indexed: 01/01/2023] Open
Abstract
One of the most paramount receptor-induced signal transduction mechanisms in hematopoietic cells is production of the lipid second messenger phosphatidylinositol(3,4,5)trisphosphate (PIP3) by class I phosphoinositide 3 kinases (PI3K). Defective PIP3 signaling impairs almost every aspect of hematopoiesis, including T cell development and function. Limiting PIP3 signaling is particularly important, because excessive PIP3 function in lymphocytes can transform them and cause blood cancers. Here, we review the key functions of PIP3 and related phosphoinositides in hematopoietic cells, with a special focus on those mechanisms dampening PIP3 production, turnover, or function. Recent studies have shown that beyond “canonical” turnover by the PIP3 phosphatases and tumor suppressors phosphatase and tensin homolog (PTEN) and SH2 domain-containing inositol-5-phosphatase-1 (SHIP-1/2), PIP3 function in hematopoietic cells can also be dampened through antagonism with the soluble PIP3 analogs inositol(1,3,4,5)tetrakisphosphate (IP4) and inositol-heptakisphosphate (IP7). Other evidence suggests that IP4 can promote PIP3 function in thymocytes. Moreover, IP4 or the kinases producing it limit store-operated Ca2+ entry through Orai channels in B cells, T cells, and neutrophils to control cell survival and function. We discuss current models for how soluble inositol phosphates can have such diverse functions and can govern as distinct processes as hematopoietic stem cell homeostasis, neutrophil macrophage and NK cell function, and development and function of B cells and T cells. Finally, we will review the pathological consequences of dysregulated IP4 activity in immune cells and highlight contributions of impaired inositol phosphate functions in disorders such as Kawasaki disease, common variable immunodeficiency, or blood cancer.
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Affiliation(s)
- Mila Elich
- Department of Cell and Molecular Biology, The Scripps Research Institute, La Jolla, CA, United States
| | - Karsten Sauer
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA, United States.,Oncology R&D, Pfizer Worldwide R&D, San Diego, CA, United States
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20
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Devkota S, Joseph RE, Boyken SE, Fulton DB, Andreotti AH. An Autoinhibitory Role for the Pleckstrin Homology Domain of Interleukin-2-Inducible Tyrosine Kinase and Its Interplay with Canonical Phospholipid Recognition. Biochemistry 2017; 56:2938-2949. [PMID: 28516764 DOI: 10.1021/acs.biochem.6b01182] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Pleckstrin homology (PH) domains are well-known as phospholipid binding modules, yet evidence that PH domain function extends beyond lipid recognition is mounting. In this work, we characterize a protein binding function for the PH domain of interleukin-2-inducible tyrosine kinase (ITK), an immune cell specific signaling protein that belongs to the TEC family of nonreceptor tyrosine kinases. Its N-terminal PH domain is a well-characterized lipid binding module that localizes ITK to the membrane via phosphatidylinositol 3,4,5-trisphosphate (PIP3) binding. Using a combination of nuclear magnetic resonance spectroscopy and mutagenesis, we have mapped an autoregulatory protein interaction site on the ITK PH domain that makes direct contact with the catalytic kinase domain of ITK, inhibiting the phospho-transfer reaction. Moreover, we have elucidated an important interplay between lipid binding by the ITK PH domain and the stability of the autoinhibitory complex formed by full length ITK. The ITK activation loop in the kinase domain becomes accessible to phosphorylation to the exogenous kinase LCK upon binding of the ITK PH domain to PIP3. By clarifying the allosteric role of the ITK PH domain in controlling ITK function, we have expanded the functional repertoire of the PH domain generally and opened the door to alternative strategies to target this specific kinase in the context of immune cell signaling.
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Affiliation(s)
- Sujan Devkota
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University , Ames, Iowa 50011, United States
| | - Raji E Joseph
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University , Ames, Iowa 50011, United States
| | - Scott E Boyken
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University , Ames, Iowa 50011, United States
| | - D Bruce Fulton
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University , Ames, Iowa 50011, United States
| | - Amy H Andreotti
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University , Ames, Iowa 50011, United States
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21
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Molecular mechanisms underlying the evolution of the slp76 signalosome. Sci Rep 2017; 7:1509. [PMID: 28473706 PMCID: PMC5431462 DOI: 10.1038/s41598-017-01660-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 03/29/2017] [Indexed: 02/07/2023] Open
Abstract
The well-defined mammalian slp76-signalosome is crucial for T-cell immune response, yet whether slp76-signalosome exists in invertebrates and how it evolved remain unknown. Here we investigated slp76-signalosome from an evolutionary perspective in amphioxus Branchiostoma belcheri (bb). We proved slp76-signalosome components bbslp76, bbGADS and bbItk are present in amphioxus and bbslp76 interacts with bbGADS and bbItk, but differences exist between the interaction manners within slp76-signalosome components of amphioxus and human (h). Specifically, bbslp76 has a unique WW-domain that blocked its association with hItk and decreased TCR-induced tyrosine-phosphorylation and NFAT-activation. Deletion of WW-domain shifted the constitutive association between bbslp76 and hPLCγ1 to a TCR-enhanced association. Among slp76-signalosome, the interaction between slp76 and PLCγ1 is the most conserved and the binding between Itk and slp76 evolved from constitutive to stimulation-regulated. Sequence alignment and 3D structural analysis of slp76-signalosome molecules from keystone species indicated slp76 evolved into a more unfolded and flexible adaptor due to lack of WW-domain and several low-complexity-regions (LCRs) while GADS turned into a larger protein by a LCR gain, thus preparing more space for nucleating the coevolving slp76-signalosome. Altogether, through deletion of WW-domain and manipulation of LCRs, slp76-signalosome evolves from a rigid and stimulation-insensitive to a more flexible and stimulation-responding complex.
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22
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Westernberg L, Conche C, Huang YH, Rigaud S, Deng Y, Siegemund S, Mukherjee S, Nosaka L, Das J, Sauer K. Non-canonical antagonism of PI3K by the kinase Itpkb delays thymocyte β-selection and renders it Notch-dependent. eLife 2016; 5. [PMID: 26880557 PMCID: PMC4764578 DOI: 10.7554/elife.10786] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 01/08/2016] [Indexed: 12/22/2022] Open
Abstract
β-selection is the most pivotal event determining αβ T cell fate. Here, surface-expression of a pre-T cell receptor (pre-TCR) induces thymocyte metabolic activation, proliferation, survival and differentiation. Besides the pre-TCR, β-selection also requires co-stimulatory signals from Notch receptors - key cell fate determinants in eukaryotes. Here, we show that this Notch-dependence is established through antagonistic signaling by the pre-TCR/Notch effector, phosphoinositide 3-kinase (PI3K), and by inositol-trisphosphate 3-kinase B (Itpkb). Canonically, PI3K is counteracted by the lipid-phosphatases Pten and Inpp5d/SHIP-1. In contrast, Itpkb dampens pre-TCR induced PI3K/Akt signaling by producing IP4, a soluble antagonist of the Akt-activating PI3K-product PIP3. Itpkb-/- thymocytes are pre-TCR hyperresponsive, hyperactivate Akt, downstream mTOR and metabolism, undergo an accelerated β-selection and can develop to CD4+CD8+ cells without Notch. This is reversed by inhibition of Akt, mTOR or glucose metabolism. Thus, non-canonical PI3K-antagonism by Itpkb restricts pre-TCR induced metabolic activation to enforce coincidence-detection of pre-TCR expression and Notch-engagement. DOI:http://dx.doi.org/10.7554/eLife.10786.001 T cells defend our body against cancer and infectious agents such as viruses. However, they can also cause rheumatoid arthritis and other autoimmune diseases by attacking healthy tissue. T cells recognize target cells via receptor proteins on their surface. To maximize the variety of infections and cancers our immune system can recognize, we generate millions of T cells with different T cell receptors every day. To ensure T cells work correctly, T cell receptors are tested at various checkpoints. The first checkpoint involves a process called beta (β) selection, during which T cells produce their first T cell receptor – the so-called pre-T cell receptor. This receptor causes T cells to divide and mature, and sets their future identity or “fate”. To complete β-selection, T cells must also receive signals from another surface receptor – one that belongs to the Notch family, which determines cell fate in many different tissues. The Notch receptor and the pre-T cell receptor both activate an enzyme called PI3K – a key mediator of β-selection. But the pre-T cell receptor also activates another enzyme called Itpkb that is required for T cell development. Westernberg, Conche et al. have now investigated how these different proteins and signaling processes work and interact during β-selection, using mice that lack several immune genes, including the gene that produces Itpkb. The results of the experiments show that during β-selection, Itpkb limits the ability of PI3K to activate some of its key target proteins. This “dampened” PI3K signaling ensures that both the pre-T cell receptor and the Notch receptor must be activated to trigger T cell maturation. Without Itpkb, β-selection can occur in the absence of Notch signaling. As Notch signaling is important for determining the fate of many different cell types, Westernberg, Conche et al.’s findings raise the possibility that Itpkb might also regulate cell fate determination in other tissues. Moreover, Itpkb may suppress tumor development, because excessive PI3K signaling drives many cancers. DOI:http://dx.doi.org/10.7554/eLife.10786.002
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Affiliation(s)
- Luise Westernberg
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, United States
| | - Claire Conche
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, United States
| | - Yina Hsing Huang
- Department of Pathology, Geisel School of Medicine, Lebanon, United States.,Departments of Microbiology and Immunology, Geisel School of Medicine, Lebanon, United States
| | - Stephanie Rigaud
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, United States
| | - Yisong Deng
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, United States
| | - Sabine Siegemund
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, United States
| | - Sayak Mukherjee
- Department of Pediatrics, The Ohio State University, Columbus, United States.,Department of Physics, The Ohio State University, Columbus, United States.,Battelle Center for Mathematical Medicine, The Ohio State University, Columbus, United States
| | - Lyn'Al Nosaka
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, United States
| | - Jayajit Das
- Department of Pediatrics, The Ohio State University, Columbus, United States.,Department of Physics, The Ohio State University, Columbus, United States.,Battelle Center for Mathematical Medicine, The Ohio State University, Columbus, United States
| | - Karsten Sauer
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, United States.,Department of Cell and Molecular Biology, The Scripps Research Institute, La Jolla, United States
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23
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Miller AT, Dahlberg C, Sandberg ML, Wen BG, Beisner DR, Hoerter JAH, Parker A, Schmedt C, Stinson M, Avis J, Cienfuegos C, McPate M, Tranter P, Gosling M, Groot-Kormelink PJ, Dawson J, Pan S, Tian SS, Seidel HM, Cooke MP. Inhibition of the Inositol Kinase Itpkb Augments Calcium Signaling in Lymphocytes and Reveals a Novel Strategy to Treat Autoimmune Disease. PLoS One 2015; 10:e0131071. [PMID: 26121493 PMCID: PMC4488288 DOI: 10.1371/journal.pone.0131071] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 05/28/2015] [Indexed: 02/02/2023] Open
Abstract
Emerging approaches to treat immune disorders target positive regulatory kinases downstream of antigen receptors with small molecule inhibitors. Here we provide evidence for an alternative approach in which inhibition of the negative regulatory inositol kinase Itpkb in mature T lymphocytes results in enhanced intracellular calcium levels following antigen receptor activation leading to T cell death. Using Itpkb conditional knockout mice and LMW Itpkb inhibitors these studies reveal that Itpkb through its product IP4 inhibits the Orai1/Stim1 calcium channel on lymphocytes. Pharmacological inhibition or genetic deletion of Itpkb results in elevated intracellular Ca2+ and induction of FasL and Bim resulting in T cell apoptosis. Deletion of Itpkb or treatment with Itpkb inhibitors blocks T-cell dependent antibody responses in vivo and prevents T cell driven arthritis in rats. These data identify Itpkb as an essential mediator of T cell activation and suggest Itpkb inhibition as a novel approach to treat autoimmune disease.
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Affiliation(s)
- Andrew T. Miller
- The Genomics Institute of the Novartis Research Foundation (GNF), San Diego, California, United States of America
- * E-mail:
| | - Carol Dahlberg
- The Genomics Institute of the Novartis Research Foundation (GNF), San Diego, California, United States of America
| | - Mark L. Sandberg
- The Genomics Institute of the Novartis Research Foundation (GNF), San Diego, California, United States of America
| | - Ben G. Wen
- The Genomics Institute of the Novartis Research Foundation (GNF), San Diego, California, United States of America
| | - Daniel R. Beisner
- The Genomics Institute of the Novartis Research Foundation (GNF), San Diego, California, United States of America
| | - John A. H. Hoerter
- The Genomics Institute of the Novartis Research Foundation (GNF), San Diego, California, United States of America
| | - Albert Parker
- The Genomics Institute of the Novartis Research Foundation (GNF), San Diego, California, United States of America
| | - Christian Schmedt
- The Genomics Institute of the Novartis Research Foundation (GNF), San Diego, California, United States of America
| | - Monique Stinson
- The Genomics Institute of the Novartis Research Foundation (GNF), San Diego, California, United States of America
| | - Jacqueline Avis
- The Genomics Institute of the Novartis Research Foundation (GNF), San Diego, California, United States of America
| | - Cynthia Cienfuegos
- The Genomics Institute of the Novartis Research Foundation (GNF), San Diego, California, United States of America
| | - Mark McPate
- Novartis Pharmaceuticals UK Limited, Respiratory Disease Area, Horsham, West Sussex, United Kingdom
| | - Pamela Tranter
- Novartis Pharmaceuticals UK Limited, Respiratory Disease Area, Horsham, West Sussex, United Kingdom
| | - Martin Gosling
- Novartis Pharmaceuticals UK Limited, Respiratory Disease Area, Horsham, West Sussex, United Kingdom
| | - Paul J. Groot-Kormelink
- Novartis Institutes for Biomedical Research, Musculoskeletal Disease Area, Basel, Switzerland
| | - Janet Dawson
- Novartis Pharma AG, Novartis Institutes for Biomed. Research, Basel, Switzerland
| | - Shifeng Pan
- The Genomics Institute of the Novartis Research Foundation (GNF), San Diego, California, United States of America
| | - Shin-Shay Tian
- The Genomics Institute of the Novartis Research Foundation (GNF), San Diego, California, United States of America
| | - H. Martin Seidel
- The Genomics Institute of the Novartis Research Foundation (GNF), San Diego, California, United States of America
| | - Michael P. Cooke
- The Genomics Institute of the Novartis Research Foundation (GNF), San Diego, California, United States of America
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24
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Siegemund S, Shepherd J, Xiao C, Sauer K. hCD2-iCre and Vav-iCre mediated gene recombination patterns in murine hematopoietic cells. PLoS One 2015; 10:e0124661. [PMID: 25884630 PMCID: PMC4401753 DOI: 10.1371/journal.pone.0124661] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Accepted: 03/17/2015] [Indexed: 12/13/2022] Open
Abstract
Cre-recombinase mediated conditional deletion of Lox-P site flanked ("floxed") genes is widely used for functional gene annotation in mice. Many different Cre-transgenic mouse lines have been developed for cell-type specific gene disruption. But often, the precise tissue-patterns of Cre activity remain incompletely characterized. Two widely used transgenes for conditional gene recombination in hematopoietic cells are Vav-iCre driven from the murine Vav1 promotor, and hCD2-iCre driven from the human CD2 promotor. Vav-iCre expresses active Cre in fetal and adult hematopoietic stem cells and all descendants, hCD2-iCre in immature and mature B and T lymphocytes. To better characterize which hematopoietic cells contain hCD2-iCre activity, we compared EYFP fluorescence in hCD2-iCre+/- R26-stop-EYFP+/- and Vav-iCre+/- R26-stop-EYFP+/-mice. R26-stop-EYFP ubiquitously encodes EYFP preceded by a floxed stop cassette. By removing it, Cre activity induces measurable EYFP expression. Our results confirm the known activity patterns for both Cre transgenes and unveil additional hCD2-iCre mediated reporter gene recombination in common lymphoid progenitors, in natural killer cells and their progenitors, and in plasmacytoid and conventional dendritic cells. This supports previously proposed common lymphoid origins for natural killer cells and subsets of dendritic cells, and indicates the need to consider pleiotropic effects when studying hCD2-iCre mediated conditional knockout mice. Vav-iCre+/- R26-stop-EYFP+/-mice did not show the non-hematopoietic recombination in vascular endothelial cells seen in other Vav-Cre mouse lines, but displayed an unexpected Vav-iCre mediated recombination in a bone cell subset lacking hematopoietic markers. This pinpoints the need to consider stromal cell contributions to phenotypes of Vav-iCre mediated conditional knockout mice. Altogether, our data provide the first detailed assessment of hCD2-iCre and Vav-iCre mediated deletion of floxed genes during lymphocyte development from hematopoietic stem cells and open up novel applications for either Cre-transgenic mouse line.
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Affiliation(s)
- Sabine Siegemund
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California, United States of America
| | - Jovan Shepherd
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California, United States of America
| | - Changchun Xiao
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California, United States of America
| | - Karsten Sauer
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California, United States of America
- Department of Cell and Molecular Biology, The Scripps Research Institute, La Jolla, California, United States of America
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25
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IP3 3-kinase B controls hematopoietic stem cell homeostasis and prevents lethal hematopoietic failure in mice. Blood 2015; 125:2786-97. [PMID: 25788703 DOI: 10.1182/blood-2014-06-583187] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 03/11/2015] [Indexed: 01/05/2023] Open
Abstract
Tight regulation of hematopoietic stem cell (HSC) homeostasis ensures lifelong hematopoiesis and prevents blood cancers. The mechanisms balancing HSC quiescence with expansion and differentiation into hematopoietic progenitors are incompletely understood. Here, we identify Inositol-trisphosphate 3-kinase B (Itpkb) as an essential regulator of HSC homeostasis. Young Itpkb(-/-) mice accumulated phenotypic HSC, which were less quiescent and proliferated more than wild-type (WT) controls. Itpkb(-/-) HSC downregulated quiescence and stemness associated, but upregulated activation, oxidative metabolism, protein synthesis, and lineage associated messenger RNAs. Although they had normal-to-elevated viability and no significant homing defects, Itpkb(-/-) HSC had a severely reduced competitive long-term repopulating potential. Aging Itpkb(-/-) mice lost hematopoietic stem and progenitor cells and died with severe anemia. WT HSC normally repopulated Itpkb(-/-) hosts, indicating an HSC-intrinsic Itpkb requirement. Itpkb(-/-) HSC showed reduced colony-forming activity and increased stem-cell-factor activation of the phosphoinositide-3-kinase (PI3K) effectors Akt/mammalian/mechanistic target of rapamycin (mTOR). This was reversed by treatment with the Itpkb product and PI3K/Akt antagonist IP4. Transcriptome changes and biochemistry support mTOR hyperactivity in Itpkb(-/-) HSC. Treatment with the mTOR-inhibitor rapamycin reversed the excessive mTOR signaling and hyperproliferation of Itpkb(-/-) HSC without rescuing colony forming activity. Thus, we propose that Itpkb ensures HSC quiescence and function through limiting cytokine-induced PI3K/mTOR signaling and other mechanisms.
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26
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Wang X, Hills LB, Huang YH. Lipid and Protein Co-Regulation of PI3K Effectors Akt and Itk in Lymphocytes. Front Immunol 2015; 6:117. [PMID: 25821452 PMCID: PMC4358224 DOI: 10.3389/fimmu.2015.00117] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Accepted: 03/02/2015] [Indexed: 12/21/2022] Open
Abstract
The phosphoinositide 3-kinase (PI 3-kinase, PI3K) pathway transduces signals critical for lymphocyte function. PI3K generates the phospholipid PIP3 at the plasma membrane to recruit proteins that contain pleckstrin homology (PH) domains – a conserved domain found in hundreds of mammalian proteins. PH domain–PIP3 interactions allow for rapid signal propagation and confer a spatial component to these signals. The kinases Akt and Itk are key PI3K effectors that bind PIP3 via their PH domains and mediate vital processes – such as survival, activation, and differentiation – in lymphocytes. Here, we review the roles and regulation of PI3K signaling in lymphocytes with a specific emphasis on Akt and Itk. We also discuss these and other PH domain-containing proteins as they relate more broadly to immune cell function. Finally, we highlight the emerging view of PH domains as multifunctional protein domains that often bind both lipid and protein substrates to exert their effects.
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Affiliation(s)
- Xinxin Wang
- California Institute for Biomedical Research , La Jolla, CA , USA
| | - Leonard Benjamin Hills
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth , Lebanon, NH , USA
| | - Yina Hsing Huang
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth , Lebanon, NH , USA ; Department of Pathology, Geisel School of Medicine at Dartmouth , Lebanon, NH , USA
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27
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Abstract
Neutrophils play critical roles in innate immunity and host defense. However, excessive neutrophil accumulation or hyper-responsiveness of neutrophils can be detrimental to the host system. Thus, the response of neutrophils to inflammatory stimuli needs to be tightly controlled. Many cellular processes in neutrophils are mediated by localized formation of an inositol phospholipid, phosphatidylinositol (3,4,5)-trisphosphate (PtdIns(3,4,5)P3), at the plasma membrane. The PtdIns(3,4,5)P3 signaling pathway is negatively regulated by lipid phosphatases and inositol phosphates, which consequently play a critical role in controlling neutrophil function and would be expected to act as ideal therapeutic targets for enhancing or suppressing innate immune responses. Here, we comprehensively review current understanding about the action of lipid phosphatases and inositol phosphates in the control of neutrophil function in infection and inflammation.
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Affiliation(s)
- Hongbo R Luo
- Department of Pathology, Harvard Medical School, Boston, MA, USA Department of Lab Medicine, Children's Hospital Boston, Dana-Farber/Harvard Cancer Center, Boston, MA, USA
| | - Subhanjan Mondal
- Department of Pathology, Harvard Medical School, Boston, MA, USA Department of Lab Medicine, Children's Hospital Boston, Dana-Farber/Harvard Cancer Center, Boston, MA, USA Promega Corporation, Madison, WI, USA
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28
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Wang Q, Vogan EM, Nocka LM, Rosen CE, Zorn JA, Harrison SC, Kuriyan J. Autoinhibition of Bruton's tyrosine kinase (Btk) and activation by soluble inositol hexakisphosphate. eLife 2015; 4:e06074. [PMID: 25699547 PMCID: PMC4384635 DOI: 10.7554/elife.06074] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2014] [Accepted: 02/19/2015] [Indexed: 01/07/2023] Open
Abstract
Bruton's tyrosine kinase (Btk), a Tec-family tyrosine kinase, is essential for B-cell function. We present crystallographic and biochemical analyses of Btk, which together reveal molecular details of its autoinhibition and activation. Autoinhibited Btk adopts a compact conformation like that of inactive c-Src and c-Abl. A lipid-binding PH-TH module, unique to Tec kinases, acts in conjunction with the SH2 and SH3 domains to stabilize the inactive conformation. In addition to the expected activation of Btk by membranes containing phosphatidylinositol triphosphate (PIP3), we found that inositol hexakisphosphate (IP6), a soluble signaling molecule found in both animal and plant cells, also activates Btk. This activation is a consequence of a transient PH-TH dimerization induced by IP6, which promotes transphosphorylation of the kinase domains. Sequence comparisons with other Tec-family kinases suggest that activation by IP6 is unique to Btk.
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Affiliation(s)
- Qi Wang
- Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, United States,California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, United States
| | - Erik M Vogan
- Beryllium Inc, Boston, United States,Laboratory of Molecular Medicine, Harvard Medical School, Howard Hughes Medical Institute, Boston, United States
| | - Laura M Nocka
- Department of Chemistry, University of California, Berkeley, Berkeley, United States
| | - Connor E Rosen
- Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, United States,California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, United States
| | - Julie A Zorn
- Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, United States,California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, United States
| | - Stephen C Harrison
- Laboratory of Molecular Medicine, Harvard Medical School, Howard Hughes Medical Institute, Boston, United States,For correspondence: (SCH)
| | - John Kuriyan
- Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, United States,California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, United States,Department of Chemistry, University of California, Berkeley, Berkeley, United States,Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, United States, (JK)
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29
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Wang X, Boyken SE, Hu J, Xu X, Rimer RP, Shea MA, Shaw AS, Andreotti AH, Huang YH. Calmodulin and PI(3,4,5)P₃ cooperatively bind to the Itk pleckstrin homology domain to promote efficient calcium signaling and IL-17A production. Sci Signal 2014; 7:ra74. [PMID: 25097034 DOI: 10.1126/scisignal.2005147] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Precise regulation of the kinetics and magnitude of Ca(2+) signaling enables this signal to mediate diverse responses, such as cell migration, differentiation, vesicular trafficking, and cell death. We showed that the Ca(2+)-binding protein calmodulin (CaM) acted in a positive feedback loop to potentiate Ca(2+) signaling downstream of the Tec kinase family member Itk. Using NMR (nuclear magnetic resonance), we mapped CaM binding to two loops adjacent to the lipid-binding pocket within the Itk pleckstrin homology (PH) domain. The Itk PH domain bound synergistically to Ca(2+)/CaM and the lipid phosphatidylinositol 3,4,5-trisphosphate [PI(3,4,5)P3], such that binding to Ca(2+)/CaM enhanced the binding to PI(3,4,5)P3 and vice versa. Disruption of CaM binding attenuated Itk recruitment to the membrane and diminished release of Ca(2+) from the endoplasmic reticulum. Moreover, disruption of this feedback loop abrogated Itk-dependent production of the proinflammatory cytokine IL-17A (interleukin-17A) by CD4(+) T cells. Additionally, we found that CaM associated with PH domains from other proteins, indicating that CaM may regulate other PH domain-containing proteins.
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Affiliation(s)
- Xinxin Wang
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Scott E Boyken
- Department of Biochemistry, Biophysics & Molecular Biology, Iowa State University, Ames, IA 50011, USA
| | - Jiancheng Hu
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Xiaolu Xu
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Ryan P Rimer
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Madeline A Shea
- Department of Biochemistry, University of Iowa, Iowa City, IA 52242, USA
| | - Andrey S Shaw
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Amy H Andreotti
- Department of Biochemistry, Biophysics & Molecular Biology, Iowa State University, Ames, IA 50011, USA
| | - Yina H Huang
- Department of Pathology & Immunology, Washington University School of Medicine, St. Louis, MO 63110, USA. Department of Pathology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756, USA. Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756, USA.
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30
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Zhong Y, Johnson AJ, Byrd JC, Dubovsky JA. Targeting Interleukin-2-Inducible T-cell Kinase (ITK) in T-Cell Related Diseases. ACTA ACUST UNITED AC 2014; 2:1-11. [PMID: 27917390 DOI: 10.14304/surya.jpr.v2n6.1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
IL2-inducible T-cell kinase (ITK), a member of the Tec family tyrosine kinases, is the predominant Tec kinase in T cells and natural killer (NK) cells mediating T cell receptor (TCR) and Fc receptor (Fc R) initiated signal transduction. ITK deficiency results in impaired T and NK cell functions, leading to various disorders including malignancies, inflammation, and autoimmune diseases. In this mini-review, the role of ITK in T cell signaling and the development of small molecule inhibitors of ITK for the treatment of T-cell related disorders is examined.
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Affiliation(s)
- Yiming Zhong
- Division of Hematology, Department of Internal Medicine, The Ohio State University, 320 W. 10th Avenue, Columbus, OH 43210, USA
| | - Amy J Johnson
- Division of Hematology, Department of Internal Medicine, The Ohio State University, 320 W. 10th Avenue, Columbus, OH 43210, USA
| | - John C Byrd
- Division of Hematology, Department of Internal Medicine, The Ohio State University, 320 W. 10th Avenue, Columbus, OH 43210, USA
| | - Jason A Dubovsky
- Division of Hematology, Department of Internal Medicine, The Ohio State University, 320 W. 10th Avenue, Columbus, OH 43210, USA
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31
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Fu G, Casas J, Rigaud S, Rybakin V, Lambolez F, Brzostek J, Hoerter JAH, Paster W, Acuto O, Cheroutre H, Sauer K, Gascoigne NRJ. Themis sets the signal threshold for positive and negative selection in T-cell development. Nature 2013; 504:441-5. [PMID: 24226767 PMCID: PMC3977001 DOI: 10.1038/nature12718] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Accepted: 09/26/2013] [Indexed: 12/31/2022]
Abstract
Development of a self-tolerant T-cell receptor (TCR) repertoire with the potential to recognize the universe of infectious agents depends on proper regulation of TCR signalling. The repertoire is whittled down during T-cell development in the thymus by the ability of quasi-randomly generated TCRs to interact with self-peptides presented by major histocompatibility complex (MHC) proteins. Low-affinity TCR interactions with self-MHC proteins generate weak signals that initiate 'positive selection', causing maturation of CD4- or CD8αβ-expressing 'single-positive' thymocytes from CD4(+)CD8αβ(+) 'double-positive' precursors. These develop into mature naive T cells of the secondary lymphoid organs. TCR interaction with high-affinity agonist self-ligands results in 'negative selection' by activation-induced apoptosis or 'agonist selection' of functionally differentiated self-antigen-experienced T cells. Here we show that positive selection is enabled by the ability of the T-cell-specific protein Themis to specifically attenuate TCR signal strength via SHP1 recruitment and activation in response to low- but not high-affinity TCR engagement. Themis acts as an analog-to-digital converter translating graded TCR affinity into clear-cut selection outcome. By dampening mild TCR signals Themis increases the affinity threshold for activation, enabling positive selection of T cells with a naive phenotype in response to low-affinity self-antigens.
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Affiliation(s)
- Guo Fu
- Department of Immunology and Microbial Science, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA
| | - Javier Casas
- 1] Department of Immunology and Microbial Science, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA [2] Department of Microbiology, Yong Loo Lin School of Medicine and Immunology Programme, National University of Singapore, 5 Science Drive 2, Singapore 117545 [3]
| | - Stephanie Rigaud
- 1] Department of Immunology and Microbial Science, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA [2]
| | - Vasily Rybakin
- 1] Department of Immunology and Microbial Science, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA [2] Department of Microbiology, Yong Loo Lin School of Medicine and Immunology Programme, National University of Singapore, 5 Science Drive 2, Singapore 117545 [3]
| | - Florence Lambolez
- Developmental Immunology, La Jolla Institute for Allergy and Immunology, 9420 Athena Circle, La Jolla, California 92037, USA
| | - Joanna Brzostek
- 1] Department of Immunology and Microbial Science, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA [2] Department of Microbiology, Yong Loo Lin School of Medicine and Immunology Programme, National University of Singapore, 5 Science Drive 2, Singapore 117545
| | - John A H Hoerter
- Department of Immunology and Microbial Science, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA
| | - Wolfgang Paster
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
| | - Oreste Acuto
- Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK
| | - Hilde Cheroutre
- Developmental Immunology, La Jolla Institute for Allergy and Immunology, 9420 Athena Circle, La Jolla, California 92037, USA
| | - Karsten Sauer
- 1] Department of Immunology and Microbial Science, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA [2] Department of Cell and Molecular Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA
| | - Nicholas R J Gascoigne
- 1] Department of Immunology and Microbial Science, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA [2] Department of Microbiology, Yong Loo Lin School of Medicine and Immunology Programme, National University of Singapore, 5 Science Drive 2, Singapore 117545
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Srivastava N, Sudan R, Kerr WG. Role of inositol poly-phosphatases and their targets in T cell biology. Front Immunol 2013; 4:288. [PMID: 24069021 PMCID: PMC3779868 DOI: 10.3389/fimmu.2013.00288] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2013] [Accepted: 09/03/2013] [Indexed: 11/13/2022] Open
Abstract
T lymphocytes play a critical role in host defense in all anatomical sites including mucosal surfaces. This not only includes the effector arm of the immune system, but also regulation of immune responses in order to prevent autoimmunity. Genetic targeting of PI3K isoforms suggests that generation of PI(3,4,5)P3 by PI3K plays a critical role in promoting effector T cell responses. Consequently, the 5'- and 3'-inositol poly-phosphatases SHIP1, SHIP2, and phosphatase and tensin homolog capable of targeting PI(3,4,5)P3 are potential genetic determinants of T cell effector functions in vivo. In addition, the 5'-inositol poly-phosphatases SHIP1 and 2 can shunt PI(3,4,5)P3 to the rare but potent signaling phosphoinositide species PI(3,4)P2 and thus these SHIP1/2, and the INPP4A/B enzymes that deplete PI(3,4)P2 may have precise roles in T cell biology to amplify or inhibit effectors of PI3K signaling that are selectively recruited to and activated by PI(3,4)P2. Here we summarize recent genetic and chemical evidence that indicates the inositol poly-phosphatases have important roles in both the effector and regulatory functions of the T cell compartment. In addition, we will discuss future genetic studies that might be undertaken to further elaborate the role of these enzymes in T cell biology as well as potential pharmaceutical manipulation of these enzymes for therapeutic purposes in disease settings where T cell function is a key in vivo target.
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Affiliation(s)
- Neetu Srivastava
- Department of Microbiology and Immunology, SUNY Upstate Medical University , Syracuse, NY , USA
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Mukherjee S, Rigaud S, Seok SC, Fu G, Prochenka A, Dworkin M, Gascoigne NRJ, Vieland VJ, Sauer K, Das J. In silico modeling of Itk activation kinetics in thymocytes suggests competing positive and negative IP4 mediated feedbacks increase robustness. PLoS One 2013; 8:e73937. [PMID: 24066087 PMCID: PMC3774804 DOI: 10.1371/journal.pone.0073937] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Accepted: 07/25/2013] [Indexed: 12/29/2022] Open
Abstract
The inositol-phosphate messenger inositol(1,3,4,5)tetrakisphosphate (IP4) is essential for thymocyte positive selection by regulating plasma-membrane association of the protein tyrosine kinase Itk downstream of the T cell receptor (TCR). IP4 can act as a soluble analog of the phosphoinositide 3-kinase (PI3K) membrane lipid product phosphatidylinositol(3,4,5)trisphosphate (PIP3). PIP3 recruits signaling proteins such as Itk to cellular membranes by binding to PH and other domains. In thymocytes, low-dose IP4 binding to the Itk PH domain surprisingly promoted and high-dose IP4 inhibited PIP3 binding of Itk PH domains. However, the mechanisms that underlie the regulation of membrane recruitment of Itk by IP4 and PIP3 remain unclear. The distinct Itk PH domain ability to oligomerize is consistent with a cooperative-allosteric mode of IP4 action. However, other possibilities cannot be ruled out due to difficulties in quantitatively measuring the interactions between Itk, IP4 and PIP3, and in generating non-oligomerizing Itk PH domain mutants. This has hindered a full mechanistic understanding of how IP4 controls Itk function. By combining experimentally measured kinetics of PLCγ1 phosphorylation by Itk with in silico modeling of multiple Itk signaling circuits and a maximum entropy (MaxEnt) based computational approach, we show that those in silico models which are most robust against variations of protein and lipid expression levels and kinetic rates at the single cell level share a cooperative-allosteric mode of Itk regulation by IP4 involving oligomeric Itk PH domains at the plasma membrane. This identifies MaxEnt as an excellent tool for quantifying robustness for complex TCR signaling circuits and provides testable predictions to further elucidate a controversial mechanism of PIP3 signaling.
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Affiliation(s)
- Sayak Mukherjee
- Battelle Center for Mathematical Medicine, The Research Institute at the Nationwide Children’s Hospital, Columbus, Ohio, United States of America
| | - Stephanie Rigaud
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California, United States of America
| | - Sang-Cheol Seok
- Battelle Center for Mathematical Medicine, The Research Institute at the Nationwide Children’s Hospital, Columbus, Ohio, United States of America
| | - Guo Fu
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California, United States of America
| | - Agnieszka Prochenka
- Battelle Center for Mathematical Medicine, The Research Institute at the Nationwide Children’s Hospital, Columbus, Ohio, United States of America
- Institute of Computer Science, Polish Academy of Sciences, Warsaw, Poland
| | - Michael Dworkin
- Battelle Center for Mathematical Medicine, The Research Institute at the Nationwide Children’s Hospital, Columbus, Ohio, United States of America
- Department of Mathematics, The Ohio State University, Columbus, Ohio, United States of America
| | - Nicholas R. J. Gascoigne
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California, United States of America
| | - Veronica J. Vieland
- Battelle Center for Mathematical Medicine, The Research Institute at the Nationwide Children’s Hospital, Columbus, Ohio, United States of America
- Department of Pediatrics, The Ohio State University, Columbus, Ohio, United States of America
- Department of Statistics, The Ohio State University, Columbus, Ohio, United States of America
| | - Karsten Sauer
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California, United States of America
- * E-mail: (KS); (JD)
| | - Jayajit Das
- Battelle Center for Mathematical Medicine, The Research Institute at the Nationwide Children’s Hospital, Columbus, Ohio, United States of America
- Department of Pediatrics, The Ohio State University, Columbus, Ohio, United States of America
- Department of Physics, The Ohio State University, Columbus, Ohio, United States of America
- Biophysics Graduate Program, The Ohio State University, Columbus, Ohio, United States of America
- * E-mail: (KS); (JD)
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Biochemical Evidence for a Putative Inositol 1,3,4,5-Tetrakisphosphate Receptor in the Olfactory System of Atlantic Salmon (Salmo salar). NEUROSCIENCE JOURNAL 2013; 2013:460481. [PMID: 26317094 PMCID: PMC4437272 DOI: 10.1155/2013/460481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/25/2012] [Revised: 02/01/2013] [Accepted: 02/04/2013] [Indexed: 11/28/2022]
Abstract
Olfactory receptor neurons in Atlantic salmon (Salmo salar) appear to use a phosphoinositide-directed phospholipase C (PLC) in odorant signal transduction. The consequences of odor-activated PLC depend on its product, inositol 1,4,5-trisphosphate (IP3). Therefore, a plasma membrane rich (PMR) fraction, previously characterized from salmon olfactory rosettes, was used to study binding sites for IP3 and its phosphorylation product, inositol 1,3,4,5-tetrakisphosphate (IP4). Binding sites for IP3 were present at the lower limit for detection in the PMR fraction but were abundant in a microsomal fraction. Binding sites for IP4 were abundant in the PMR fraction and thus colocalized in the same subcellular fraction with odorant receptors for amino acids and bile acids. Binding of IP4 was saturable and high affinity (Kd = 83 nM). The rank order for potency of inhibition of IP4 by other inositol polyphosphates (InsPx) followed the phosphorylation number with InsP6 > InsP5 > other InsP4 isomers > InsP3 isomers > InsP2 isomers, with the latter showing no activity. The consequences of PLC activity in this system may be dictated in part by a putative receptor for IP4.
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Abstract
Natural killer (NK) cells have important functions in cancer immunosurveillance, BM allograft rejection, fighting infections, tissue homeostasis, and reproduction. NK cell-based therapies are promising treatments for blood cancers. Overcoming their currently limited efficacy requires a better understanding of the molecular mechanisms controlling NK cell development and dampening their effector functions. NK cells recognize the loss of self-antigens or up-regulation of stress-induced ligands on pathogen-infected or tumor cells through invariant NK cell receptors (NKRs), and then kill such stressed cells. Two second-messenger pathways downstream of NKRs are required for NK cell maturation and effector responses: PIP(3) generation by PI3K and generation of diacylglycerol and IP(3) by phospholipase-Cγ (PLCγ). In the present study, we identify a novel role for the phosphorylated IP(3) metabolite inositol (1,3,4,5)tetrakisphosphate (IP(4)) in NK cells. IP(4) promotes NK cell terminal differentiation and acquisition of a mature NKR repertoire. However, in mature NK cells, IP(4) limits NKR-induced IFNγ secretion, granule exocytosis, and target-cell killing, in part by inhibiting the PIP(3) effector-kinase Akt. This identifies IP(4) as an important novel regulator of NK cell development and function and expands our understanding of the therapeutically important mechanisms dampening NK cell responses. Our results further suggest that PI3K regulation by soluble IP(4) is a broadly important signaling paradigm.
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Hirve N, Levytskyy RM, Rigaud S, Guimond DM, Zal T, Sauer K, Tsoukas CD. A conserved motif in the ITK PH-domain is required for phosphoinositide binding and TCR signaling but dispensable for adaptor protein interactions. PLoS One 2012; 7:e45158. [PMID: 23028816 PMCID: PMC3445557 DOI: 10.1371/journal.pone.0045158] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2012] [Accepted: 08/15/2012] [Indexed: 01/20/2023] Open
Abstract
Binding of the membrane phospholipid phosphatidylinositol 3,4,5-trisphosphate (PIP(3)) to the Pleckstrin Homology (PH) domain of the Tec family protein tyrosine kinase, Inducible T cell Kinase (ITK), is critical for the recruitment of the kinase to the plasma membrane and its co-localization with the TCR-CD3 molecular complex. Three aromatic residues, termed the FYF motif, located in the inner walls of the phospholipid-binding pocket of the ITK PH domain, are conserved in the PH domains of all Tec kinases, but not in other PH-domain containing proteins, suggesting an important function of the FYF motif in the Tec kinase family. However, the biological significance of the FYF amino acid motif in the ITK-PH domain is unknown. To elucidate it, we have tested the effects of a FYF triple mutant (F26S, Y90F, F92S), henceforth termed FYF-ITK mutant, on ITK function. We found that FYF triple mutation inhibits the TCR-induced production of IL-4 by impairing ITK binding to PIP(3), reducing ITK membrane recruitment, inducing conformational changes at the T cell-APC contact site, and compromising phosphorylation of ITK and subsequent phosphorylation of PLCγ(1). Interestingly, however, the FYF motif is dispensable for the interaction of ITK with two of its signaling partners, SLP-76 and LAT. Thus, the FYF mutation uncouples PIP(3)-mediated ITK membrane recruitment from the interactions of the kinase with key components of the TCR signalosome and abrogates ITK function in T cells.
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Affiliation(s)
- Nupura Hirve
- Molecular Biology Institute and Center for Microbial Sciences, Department of Biology, San Diego State University, San Diego, California, United States of America
| | - Roman M. Levytskyy
- Molecular Biology Institute and Center for Microbial Sciences, Department of Biology, San Diego State University, San Diego, California, United States of America
| | - Stephanie Rigaud
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California, United States of America
| | - David M. Guimond
- Molecular Biology Institute and Center for Microbial Sciences, Department of Biology, San Diego State University, San Diego, California, United States of America
| | - Tomasz Zal
- MD Anderson Cancer Center, Department of Immunology, The University of Texas, Houston, Texas, United States of America
| | - Karsten Sauer
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California, United States of America
| | - Constantine D. Tsoukas
- Molecular Biology Institute and Center for Microbial Sciences, Department of Biology, San Diego State University, San Diego, California, United States of America
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37
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Kannan A, Huang W, Huang F, August A. Signal transduction via the T cell antigen receptor in naïve and effector/memory T cells. Int J Biochem Cell Biol 2012; 44:2129-34. [PMID: 22981631 DOI: 10.1016/j.biocel.2012.08.023] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2012] [Revised: 08/27/2012] [Accepted: 08/28/2012] [Indexed: 10/27/2022]
Abstract
T cells play an indispensable role in immune defense against infectious agents, but can also be pathogenic. These T cells develop in the thymus, are exported into the periphery as naïve cells and participate in immune responses. Upon recognition of antigen, they are activated and differentiate into effector and memory T cells. While effector T cells carry out the function of the immune response, memory T cells can last up to the life time of the individual, and are activated by subsequent antigenic exposure. Throughout this life cycle, the T cell uses the same receptor for antigen, the T cell Receptor, a complex multi-subunit receptor. Recognition of antigen presented by peptide/MHC complexes on antigen presenting cells unleashes signaling pathways that control T cell activation at each stage. In this review, we discuss the signals regulated by the T cell receptor in naïve and effector/memory T cells.
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Affiliation(s)
- Arun Kannan
- The Department of Microbiology & Immunology, Cornell University, Ithaca, NY, USA
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38
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August A, Ragin MJ. Regulation of T-cell responses and disease by tec kinase Itk. Int Rev Immunol 2012; 31:155-65. [PMID: 22449075 DOI: 10.3109/08830185.2012.668981] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Itk is a member of the Tec family tyrosine kinases involved in T-cell receptor signaling. The authors review the background and most recent findings of the role of Itk T-cell activation and development of αβ T cells. They also discuss the role of Itk in development of nonconventional T cells, including CD8(+) innate memory phenotype T cells, different γδ T-cell populations, and invariant NKT cells. They close by reviewing the regulation of T helper differentiation and cytokine secretion, the immune response to infectious disease, and diseases such as allergic asthma and atopic dermatitis by Itk.
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Affiliation(s)
- Avery August
- Department of Microbiology & Immunology, Cornell University, Ithaca, New York, USA.
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39
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Boyken SE, Fulton DB, Andreotti AH. Rescue of the aggregation prone Itk Pleckstrin Homology domain by two mutations derived from the related kinases, Btk and Tec. Protein Sci 2012; 21:1288-97. [PMID: 22761113 DOI: 10.1002/pro.2114] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Revised: 06/19/2012] [Accepted: 06/20/2012] [Indexed: 12/18/2022]
Abstract
IL-2 inducible T-cell kinase (Itk) is a Tec family non-receptor tyrosine kinase involved in signaling downstream of the T-cell receptor. Itk contains an amino-terminal Pleckstrin Homology (PH) domain that binds phosphatidylinositol (3,4,5)-trisphosphate, recruiting Itk to the plasma membrane upon T-cell receptor activation. In addition to phosphoinositide binding, accumulating data suggest that the Itk PH domain likely mediates additional interactions outside of the phosphoinositide ligand binding pocket. The structural basis for additional PH domain functions remains elusive because of the poor recombinant expression and in vitro solution behavior of the Itk PH domain. Here, we determine that the lone α-helix in the Itk PH domain is responsible for the poor solution properties and that mutation of just two residues in the Itk α-helix to the corresponding amino acids in Btk or Tec dramatically improves the soluble recombinant expression and solution behavior of the Itk PH domain. We present this double mutant as a valuable tool to characterize the structure and function of the Itk PH domain. It is also interesting to note that the precise sites of mutation identified in this study appear as somatic mutations associated with cancerous tissue. Collectively, the findings suggest that the two helical residues in the Itk PH domain may serve an important and unique structural role in wild-type Itk that differentiates this tyrosine kinase from its related family members.
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Affiliation(s)
- Scott E Boyken
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa, USA
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In Vivo Consequences of Disrupting SH3-Mediated Interactions of the Inducible T-Cell Kinase. JOURNAL OF SIGNAL TRANSDUCTION 2012; 2012:694386. [PMID: 22649724 PMCID: PMC3357558 DOI: 10.1155/2012/694386] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/20/2012] [Accepted: 02/24/2012] [Indexed: 01/05/2023]
Abstract
ITK-SH3-mediated interactions, both with exogenous ligands and via intermolecular self-association with ITK-SH2, have been shown to be important for regulation of ITK activity. The biological significance of these competing SH3 interactions is not completely understood. A mutant of ITK where substitution of the SH3 domain with that of the related kinase BTK (ITK-BTK(SH3)) was used to disrupt intermolecular self-association of ITK while maintaining canonical binding to exogenous ligands such as SLP-76. ITK-BTK(SH3) displays reduced association with SLP-76 leading to inefficient transphosphorylation, reduced phosphorylation of PLCγ1, and diminished Th2 cytokine production. In contrast, ITK-BTK(SH3) displays no defect in its localization to the T-cell-APC contact site. Another mutation, Y511F, in the activation loop of ITK, impairs ITK activation. T cells expressing ITK-Y511F display defective phosphorylation of ITK and its downstream target PLCγ1, as well as significant inhibition of Th2 cytokines. In contrast, the inducible localization of ITK-Y511F to the T cell-APC contact site and its association with SLP-76 are not affected. The presented data lend further support to the hypothesis that precise interactions between ITK and its signaling partners are required to support ITK signaling downstream of the TCR.
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Boucheron N, Ellmeier W. The Role of Tec Family Kinases in the Regulation of T-helper-cell Differentiation. Int Rev Immunol 2012; 31:133-54. [DOI: 10.3109/08830185.2012.664798] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Abstract
The inositol (1,4,5) trisphosphate 3-kinases comprise a family of enzymes (A, B, and C) that phosphorylate the calcium mobilising molecule inositol (1,4,5) trisphosphate (IP3) to generate inositol (1,3,4,5) tetrakisphosphate. This molecule can function as a second messenger, but its roles are not completely understood. The A isoform of inositol (1,4,5) trisphosphate 3-kinase localises to filamentous actin within dendritic spines in the hippocampus and is implicated in the regulation of spine morphology and long term potentiation, however the mechanisms through which it signals in neuronal cells are not completely understood. We have used NGF driven neurite outgrowth from PC12 cells as a platform to examine the impact of signaling via inositol (1,4,5) trisphosphate 3-kinase activity in a neuronal cell. We have found that the catalytic activity of the enzyme opposes neurite outgrowth, whilst pharmacological inhibition of inositol (1,4,5) trisphosphate 3-kinase leads to a significant increase in neurite outgrowth, and we show that the reduction in neurite outgrowth in response to inositol (1,4,5) trisphosphate 3-kinase activity correlates with reduced ERK activity as determined by western blotting using phosphorylation-specific antibodies. Our findings suggest a novel neuronal signaling pathway linking metabolism of IP3 to signaling via ERK.
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Loss-of-function mutations within the IL-2 inducible kinase ITK in patients with EBV-associated lymphoproliferative diseases. Leukemia 2012; 26:963-71. [PMID: 22289921 DOI: 10.1038/leu.2011.371] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The purpose of this study was the appraisal of the clinical and functional consequences of germline mutations within the gene for the IL-2 inducible T-cell kinase, ITK. Among patients with Epstein-Barr virus-driven lymphoproliferative disorders (EBV-LPD), negative for mutations in SH2D1A and XIAP (n=46), we identified two patients with R29H or D500T,F501L,M503X mutations, respectively. Human wild-type (wt) ITK, but none of the mutants, was able to rescue defective calcium flux in murine Itk(-/-) T cells. Pulse-chase experiments showed that ITK mutations lead to varying reductions of protein half-life from 25 to 69% as compared with wt ITK (107 min). The pleckstrin homology domain of wt ITK binds most prominently to phosphatidylinositol monophosphates (PI(3)P, PI(4)P, PI(5)P) and to lesser extend to its double or triple phosphorylated derivates (PIP2, PIP3), interactions which were dramatically reduced in the patient with the ITK(R29H) mutant. ITK mutations are distributed over the entire protein and include missense, nonsense and indel mutations, reminiscent of the situation in its sister kinase in B cells, Bruton's tyrosine kinase.
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44
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Shears SB, Ganapathi SB, Gokhale NA, Schenk TMH, Wang H, Weaver JD, Zaremba A, Zhou Y. Defining signal transduction by inositol phosphates. Subcell Biochem 2012; 59:389-412. [PMID: 22374098 PMCID: PMC3925325 DOI: 10.1007/978-94-007-3015-1_13] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Ins(1,4,5)P(3) is a classical intracellular messenger: stimulus-dependent changes in its levels elicits biological effects through its release of intracellular Ca(2+) stores. The Ins(1,4,5)P(3) response is "switched off" by its metabolism to a range of additional inositol phosphates. These metabolites have themselves come to be collectively described as a signaling "family". The validity of that latter definition is critically examined in this review. That is, we assess the strength of the hypothesis that Ins(1,4,5)P(3) metabolites are themselves "classical" signals. Put another way, what is the evidence that the biological function of a particular inositol phosphate depends upon stimulus dependent changes in its levels? In this assessment, examples of an inositol phosphate acting as a cofactor (i.e. its function is not stimulus-dependent) do not satisfy our signaling criteria. We conclude that Ins(3,4,5,6)P(4) is, to date, the only Ins(1,4,5)P(3) metabolite that has been validated to act as a second messenger.
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Key Words
- adenosine deaminase
- akt
- β-cells
- calcium
- camp
- camkii
- chloride channel
- clc3
- compartmentalization
- dna repair
- endosomes
- erk
- frizzled receptor
- gap1ip4bp
- mrna export
- ins(1,4,5)p3
- ins(1,4,5)p4 receptor
- ins(1,3,4)p3
- ins(1,3,4,5)p4
- ins(1,3,4,5)p4 receptor
- ins(1,4,5,6)p4
- ins(3,4,5,6)p4
- ins(1,3,4,5,6)p5
- insp6
- insulin
- ipmk
- ipk2
- ip5k
- itp
- itpk1
- itpkb
- lymphocytes
- ku
- neutrophils
- protein phosphatase
- ptdins(4,5)p2
- ptdins(3,4,5)p3
- ph domain
- pten
- rasa3
- transcription
- wnt ligand
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Affiliation(s)
- Stephen B Shears
- Inositol Signaling Section, Laboratory of Signal Transduction, NIEHS, NIH, DHHS, Research Triangle Park, 27709, NC, USA, USA,
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Abstract
Inositol pyrophosphates are highly energetic inositol polyphosphate molecules present in organisms from slime molds and yeast to mammals. Distinct classes of enzymes generate different forms of inositol pyrophosphates. The biosynthesis of these substances principally involves phosphorylation of inositol hexakisphosphate (IP₆) to generate the pyrophosphate IP₇. Initial insights into functions of these substances derived primarily from yeast, which contain a single isoform of IP₆ kinase (yIP₆K), as well as from the slime mold Dictyostelium. Mammalian functions for inositol pyrophosphates have been investigated by using cell lines to establish roles in various processes, including insulin secretion and apoptosis. More recently, mice with targeted deletion of IP₆K isoforms as well as the related inositol polyphosphate multikinase (IPMK) have substantially enhanced our understanding of inositol polyphosphate physiology. Phenotypic alterations in mice lacking inositol hexakisphosphate kinase 1 (IP₆K1) reveal signaling roles for these molecules in insulin homeostasis, obesity, and immunological functions. Inositol pyrophosphates regulate these processes at least in part by inhibiting activation of the serine-threonine kinase Akt. Similar studies of IP₆K2 establish this enzyme as a cell death inducer acting by stimulating the proapoptotic protein p53. IPMK is responsible for generating the inositol phosphate IP₅ but also has phosphatidylinositol 3-kinase activity--that participates in activation of Akt. Here, we discuss recent advances in understanding the physiological functions of the inositol pyrophosphates based in substantial part on studies in mice with deletion of IP₆K isoforms. These findings highlight the interplay of IPMK and IP₆K in regulating growth factor and nutrient-mediated cell signaling.
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Affiliation(s)
- Anutosh Chakraborty
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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46
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Qi Q, Kannan AK, August A. Structure and function of Tec family kinase Itk. Biomol Concepts 2011; 2:223-32. [PMID: 25962031 DOI: 10.1515/bmc.2011.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2011] [Accepted: 05/11/2011] [Indexed: 11/15/2022] Open
Abstract
Itk is a member of the Tec family of kinases that is expressed predominantly in T cells. Itk regulates the T cell receptor signaling pathway to modulate T cell development and T helper cell differentiation, particularly Th2 differentiation. Itk is also important for the development and function of iNKT cells. In this review we discuss current progress on our understanding of the structure, activation and signaling pathway of Itk, in addition to inhibitors that have been developed, which target this kinase. We also place in context the function of Itk, available inhibitors and potential use in treating disease.
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47
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Itk: the rheostat of the T cell response. JOURNAL OF SIGNAL TRANSDUCTION 2011; 2011:297868. [PMID: 21747996 PMCID: PMC3116522 DOI: 10.1155/2011/297868] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2010] [Accepted: 01/19/2011] [Indexed: 12/28/2022]
Abstract
The nonreceptor tyrosine kinase Itk plays a key role in TCR-initiated signaling that directly and significantly affects the regulation of PLCγ1 and the consequent mobilization of Ca2+. Itk also participates in the regulation of cytoskeletal reorganization as well as cellular adhesion, which is necessary for a productive T cell response. The functional cellular outcome of these molecular regulations by Itk renders it an important mediator of T cell development and differentiation. This paper encompasses the structure of Itk, the signaling parameters leading to Itk activation, and Itk effects on molecular pathways resulting in functional cellular outcomes. The incorporation of these factors persuades one to believe that Itk serves as a modulator, or rheostat, critically fine-tuning the T cell response.
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48
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Abstract
Second messenger molecules relay, amplify, and diversify cell surface receptor signals. Two important examples are phosphorylated D-myo-inositol derivatives, such as phosphoinositide lipids within cellular membranes, and soluble inositol phosphates. Here, we review how phosphoinositide metabolism generates multiple second messengers with important roles in T-cell development and function. They include soluble inositol(1,4,5)trisphosphate, long known for its Ca(2+)-mobilizing function, and phosphatidylinositol(3,4,5)trisphosphate, whose generation by phosphoinositide 3-kinase and turnover by the phosphatases PTEN and SHIP control a key "hub" of TCR signaling. More recent studies unveiled important second messenger functions for diacylglycerol, phosphatidic acid, and soluble inositol(1,3,4,5)tetrakisphosphate (IP(4)) in immune cells. Inositol(1,3,4,5)tetrakisphosphate acts as a soluble phosphatidylinositol(3,4,5)trisphosphate analog to control protein membrane recruitment. We propose that phosphoinositide lipids and soluble inositol phosphates (IPs) can act as complementary partners whose interplay could have broadly important roles in cellular signaling.
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Affiliation(s)
- Yina H Huang
- Department of Pathology, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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Shears SB, Gokhale NA, Wang H, Zaremba A. Diphosphoinositol polyphosphates: what are the mechanisms? ACTA ACUST UNITED AC 2010; 51:13-25. [PMID: 21035493 DOI: 10.1016/j.advenzreg.2010.09.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2010] [Accepted: 09/17/2010] [Indexed: 12/30/2022]
Abstract
In countries where adulthood is considered to be attained at age eighteen, 2011 can be the point at which the diphosphoinositol polyphosphates might formally be described as "coming of age", since these molecules were first fully defined in 1993 (Menniti et al., 1993; Stephens et al., 1993b). But from a biological perspective, these polyphosphates cannot quite be considered to have matured into the status of being independently-acting intracellular signals. This review has discussed several of the published proposals for mechanisms by which the diphosphoinositol polyphosphates might act. We have argued that all of these hypotheses need further development.We also still do not know a single molecular mechanism by which a change in the levels of a particular diphosphoinositol polyphosphate can be controlled. Yet, despite all these gaps in our understanding, there is an enduring anticipation that these molecules have great potential in the signaling field. Reflecting our expectations of all teenagers, it should be our earnest hope that in the near future the diphosphoinositol polyphosphates will finally grow up.
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Affiliation(s)
- Stephen B Shears
- Inositol Signaling Group, Laboratory of Signal Transduction, National Institute of Environmental Health Sciences, NIH, DHHS, Research Triangle Park, NC 27709, USA.
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Regulation of B cell survival, development and function by inositol 1,4,5-trisphosphate 3-kinase B (Itpkb). ACTA ACUST UNITED AC 2010; 51:66-73. [PMID: 21035494 DOI: 10.1016/j.advenzreg.2010.08.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2010] [Accepted: 08/31/2010] [Indexed: 10/18/2022]
Abstract
In mammals, Ins(1,4,5)P3, the well known calcium mobilization messenger, is phosphorylated in the cytosol at the 3-position of the inositol ring to yield Ins(1,3,4,5)P4 by Ins(1,4,5)P3 3-kinases A, B and C isoforms as well as by inositol polyphosphate multikinase (Ipmk). Studies in gene-deficient mice have revealed that these enzymes and Ins(1,3,4,5)P4, their reaction product, play essential role in multiple physiological processes, ranging from synaptic plasticity, hematopoietic cell survival, development and function, to mRNA export, transcriptional regulation and chromatin remodelling. Rather than to provide an unique and “universal” mechanism of Ins(1,3,4,5)P4 action, these studies in genetically-modified mice point for a role of this inositide in the control of calcium mobilization, of the subcellular localisation of PH domain-containing target proteins, and of higher inositol phosphate production. Mice deficient for the B isoform of inositol 1,4,5-trisphosphate 3-kinase (Itpkb) develop profound alterations in T and B cells as well as in neutrophils and mast cells. Our recent studies indicate that the 3-kinase Itpkb and Ins(1,3,4,5)P4 are important for the survival of naïve mature B cells and the control of proapoptotic Bim protein expression, rather than for the control of B cell transition from one developmental stage to another. They also suggest that Itpkb is an important component in the control of B cell anergy.
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