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Powis G, Meuillet EJ, Indarte M, Booher G, Kirkpatrick L. Pleckstrin Homology [PH] domain, structure, mechanism, and contribution to human disease. Biomed Pharmacother 2023; 165:115024. [PMID: 37399719 DOI: 10.1016/j.biopha.2023.115024] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 06/14/2023] [Indexed: 07/05/2023] Open
Abstract
The pleckstrin homology [PH] domain is a structural fold found in more than 250 proteins making it the 11th most common domain in the human proteome. 25% of family members have more than one PH domain and some PH domains are split by one, or several other, protein domains although still folding to give functioning PH domains. We review mechanisms of PH domain activity, the role PH domain mutation plays in human disease including cancer, hyperproliferation, neurodegeneration, inflammation, and infection, and discuss pharmacotherapeutic approaches to regulate PH domain activity for the treatment of human disease. Almost half PH domain family members bind phosphatidylinositols [PIs] that attach the host protein to cell membranes where they interact with other membrane proteins to give signaling complexes or cytoskeleton scaffold platforms. A PH domain in its native state may fold over other protein domains thereby preventing substrate access to a catalytic site or binding with other proteins. The resulting autoinhibition can be released by PI binding to the PH domain, or by protein phosphorylation thus providing fine tuning of the cellular control of PH domain protein activity. For many years the PH domain was thought to be undruggable until high-resolution structures of human PH domains allowed structure-based design of novel inhibitors that selectively bind the PH domain. Allosteric inhibitors of the Akt1 PH domain have already been tested in cancer patients and for proteus syndrome, with several other PH domain inhibitors in preclinical development for treatment of other human diseases.
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Affiliation(s)
- Garth Powis
- PHusis Therapeutics Inc., 6019 Folsom Drive, La Jolla, CA 92037, USA.
| | | | - Martin Indarte
- PHusis Therapeutics Inc., 6019 Folsom Drive, La Jolla, CA 92037, USA
| | - Garrett Booher
- PHusis Therapeutics Inc., 6019 Folsom Drive, La Jolla, CA 92037, USA
| | - Lynn Kirkpatrick
- PHusis Therapeutics Inc., 6019 Folsom Drive, La Jolla, CA 92037, USA
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Yin Z, Zou Y, Wang D, Huang X, Xiong S, Cao L, Zhang Y, Sun Y, Zhang N. Regulation of the Tec family of non-receptor tyrosine kinases in cardiovascular disease. Cell Death Dis 2022; 8:119. [PMID: 35296647 PMCID: PMC8927484 DOI: 10.1038/s41420-022-00927-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 02/14/2022] [Accepted: 02/25/2022] [Indexed: 12/04/2022]
Abstract
Tyrosine phosphorylation by protein tyrosine kinases (PTKs) is a type of post-translational modification. Tec kinases, which are a subfamily of non-receptor PTKs, were originally discovered in the hematopoietic system and include five members: Tec, Btk, Itk/Emt/Tsk, Etk/Bmx, and Txk/Rlk. With the progression of modern research, certain members of the Tec family of kinases have been found to be expressed outside the hematopoietic system and are involved in the development and progression of a variety of diseases. The role of Tec family kinases in cardiovascular disease is receiving increasing attention. Tec kinases are involved in the occurrence and progression of ischemic heart disease, atherosclerosis, cardiac dysfunction associated with sepsis, atrial fibrillation, myocardial hypertrophy, coronary atherosclerotic heart disease, and myocardial infarction and post-myocardial. However, no reviews have comprehensively clarified the role of Tec kinases in the cardiovascular system. Therefore, this review summarizes research on the role of Tec kinases in cardiovascular disease, providing new insights into the prevention and treatment of cardiovascular disease.
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Affiliation(s)
- Zeyu Yin
- Department of Cardiology, the First Hospital of China Medical University, Shenyang, Liaoning, China
| | - Yuanming Zou
- Department of Cardiology, the First Hospital of China Medical University, Shenyang, Liaoning, China
| | - Dong Wang
- Department of Cardiology, the First Hospital of China Medical University, Shenyang, Liaoning, China
| | - Xinyue Huang
- Department of Cardiology, the First Hospital of China Medical University, Shenyang, Liaoning, China
| | - Shengjun Xiong
- Department of Cardiology, the First Hospital of China Medical University, Shenyang, Liaoning, China
| | - Liu Cao
- Key Laboratory of Medical Cell Biology, Ministry of Education; Institute of Translational Medicine, China Medical University; Liaoning Province Collaborative Innovation Center of Aging Related Disease Diagnosis and Treatment and Prevention, Shenyang, Liaoning, China
| | - Ying Zhang
- Department of Cardiology, the First Hospital of China Medical University, Shenyang, Liaoning, China.
| | - Yingxian Sun
- Department of Cardiology, the First Hospital of China Medical University, Shenyang, Liaoning, China.
| | - Naijin Zhang
- Department of Cardiology, the First Hospital of China Medical University, Shenyang, Liaoning, China.
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Lin H. Protein cysteine palmitoylation in immunity and inflammation. FEBS J 2021; 288:7043-7059. [PMID: 33506611 PMCID: PMC8872633 DOI: 10.1111/febs.15728] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 12/24/2020] [Accepted: 01/25/2021] [Indexed: 07/24/2023]
Abstract
Protein cysteine palmitoylation, or S-palmitoylation, has been known for about 40 years, and thousands of proteins in humans are known to be modified. Because of the large number of proteins modified, the importance and physiological functions of S-palmitoylation are enormous. However, most of the known physiological functions of S-palmitoylation can be broadly classified into two categories, neurological or immunological. This review provides a summary on the function of S-palmitoylation from the immunological perspective. Several important immune signaling pathways are discussed, including STING, NOD1/2, JAK-STAT in cytokine signaling, T-cell receptor signaling, chemotactic GPCR signaling, apoptosis, phagocytosis, and endothelial and epithelial integrity. This review is not meant to be comprehensive, but rather focuses on specific examples to highlight the versatility of palmitoylation in regulating immune signaling, as well as the potential and challenges of targeting palmitoylation to treat immune diseases.
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Affiliation(s)
- Hening Lin
- Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, USA
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Agrebi N, Gentilcore G, Grivel JC, Alkhayer G, Hassoun J, Hassan A, Adeli M, Lo B. X-Linked Agammaglobulinemia Case with TH Domain Missense Mutation in Bruton Tyrosine Kinase. J Clin Immunol 2021; 41:825-828. [PMID: 33501616 PMCID: PMC8068703 DOI: 10.1007/s10875-020-00962-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 12/29/2020] [Indexed: 12/02/2022]
Affiliation(s)
| | | | | | | | | | - Amel Hassan
- Division of Allergy & Immunology, Sidra Medicine, Doha, Qatar
| | - Mehdi Adeli
- Division of Allergy & Immunology, Sidra Medicine, Doha, Qatar
| | - Bernice Lo
- Research Department, Sidra Medicine, Doha, Qatar.
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Liu T, Li Y, Su H, Zhang H, Jones D, Zhou HJ, Ji W, Min W. Nuclear localization of the tyrosine kinase BMX mediates VEGFR2 expression. J Cell Mol Med 2020; 24:126-138. [PMID: 31642192 PMCID: PMC6933376 DOI: 10.1111/jcmm.14663] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 08/15/2019] [Accepted: 08/22/2019] [Indexed: 12/12/2022] Open
Abstract
Vascular endothelial growth factor receptors (VEGFRs) are major contributors to angiogenesis and lymphangiogenesis through the binding of VEGF ligands. We have previously shown that the bone marrow tyrosine kinase BMX is critical for inflammatory angiogenesis via its direct transactivation of VEGFR2. In the present study, we show that siRNA-mediated silencing of BMX led to a significant decrease in the total levels of VEGFR2 mRNA and protein, without affecting their stability, in human endothelial cells (ECs). Interestingly, BMX was detected in the nuclei of ECs, and the SH3 domain of BMX was necessary for its nuclear localization. Luciferase assays showed a significant decrease in the Vegfr2 (kdr) gene promoter activity in ECs after BMX silencing, indicating that BMX is necessary for Vegfr2 transcription. In addition, we found that wild-type BMX, but not a catalytic inactive mutant BMX-K445R, promoted Vegfr2 promoter activity and VEGF-induced EC migration and tube sprouting. Mechanistically, we show that the enhancement of Vegfr2 promoter activity by BMX was mediated by Sp1, a transcription factor critical for the Vegfr2 promoter. Loss of BMX significantly reduced Sp1 binding to the Vegfr2 promoter as assayed by chromatin immunoprecipitation assays. Wild-type BMX, but not a kinase-inactive form of BMX, associated with and potentially phosphorylated Sp1. Moreover, a nuclear-targeted BMX (NLS-BMX), but not cytoplasm-localized form (NES-BMX), bound to Sp1 and augmented VEGFR2 expression. In conclusion, we uncovered a novel function of nuclear-localized BMX in regulating VEGFR2 expression and angiogenesis, suggesting that BMX is a therapeutic target for angiogenesis-related diseases.
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Affiliation(s)
- Tingting Liu
- The Center for Translational MedicineThe First Affiliated HospitalSun Yat‐sen UniversityGuangzhouGuangdongChina
| | - Yonghao Li
- Zhongshan Ophthalmic CenterSun Yat‐sen UniversityGuangzhouGuangdongChina
| | - Hong Su
- The Center for Translational MedicineThe First Affiliated HospitalSun Yat‐sen UniversityGuangzhouGuangdongChina
| | - Haifeng Zhang
- Department of Pathology and the Vascular Biology and Therapeutics ProgramYale University School of MedicineNew HavenCTUSA
| | - Dennis Jones
- Department of Pathology and Laboratory MedicineBoston University School of MedicineBostonMAUSA
| | - Huanjiao Jenny Zhou
- Department of Pathology and the Vascular Biology and Therapeutics ProgramYale University School of MedicineNew HavenCTUSA
| | - Weidong Ji
- The Center for Translational MedicineThe First Affiliated HospitalSun Yat‐sen UniversityGuangzhouGuangdongChina
| | - Wang Min
- Department of Pathology and the Vascular Biology and Therapeutics ProgramYale University School of MedicineNew HavenCTUSA
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A negative role for the interleukin-2-inducible T-cell kinase (ITK) in human Foxp3+ TREG differentiation. PLoS One 2019; 14:e0215963. [PMID: 31022269 PMCID: PMC6483201 DOI: 10.1371/journal.pone.0215963] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Accepted: 04/11/2019] [Indexed: 01/13/2023] Open
Abstract
The Tec kinases ITK (interleukin-2-inducible T-cell kinase) and RLK (resting lymphocyte kinase) are critical components of the proximal TCR/CD3 signal transduction machinery, and data in mice suggest that ITK negatively modulates regulatory T cell (TREG) differentiation. However, whether Tec kinases modulate TREG development and/or function in human T cells remains unknown. Using a novel self-delivery siRNA platform (sdRNA), we found that ITK knockdown in human primary naïve peripheral blood CD4 T cells increased Foxp3+ expression under both TREG and T helper priming conditions. TREG differentiated under ITK knockdown conditions exhibited enhanced expression of the co-inhibitory receptor PD-1 and were suppressive in a T cell proliferation assay. ITK knockdown decreased IL-17A production in T cells primed under Th17 conditions and promoted Th1 differentiation. Lastly, a dual ITK/RLK Tec kinase inhibitor did not induce Foxp3 in CD4 T cells, but conversely abrogated Foxp3 expression induced by ITK knockdown. Our data suggest that targeting ITK in human T cells may be an effective approach to boost TREG in the context of autoimmune diseases, but concomitant inhibition of other Tec family kinases may negate this effect.
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Shah NH, Amacher JF, Nocka LM, Kuriyan J. The Src module: an ancient scaffold in the evolution of cytoplasmic tyrosine kinases. Crit Rev Biochem Mol Biol 2018; 53:535-563. [PMID: 30183386 PMCID: PMC6328253 DOI: 10.1080/10409238.2018.1495173] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Tyrosine kinases were first discovered as the protein products of viral oncogenes. We now know that this large family of metazoan enzymes includes nearly one hundred structurally diverse members. Tyrosine kinases are broadly classified into two groups: the transmembrane receptor tyrosine kinases, which sense extracellular stimuli, and the cytoplasmic tyrosine kinases, which contain modular ligand-binding domains and propagate intracellular signals. Several families of cytoplasmic tyrosine kinases have in common a core architecture, the "Src module," composed of a Src-homology 3 (SH3) domain, a Src-homology 2 (SH2) domain, and a kinase domain. Each of these families is defined by additional elaborations on this core architecture. Structural, functional, and evolutionary studies have revealed a unifying set of principles underlying the activity and regulation of tyrosine kinases built on the Src module. The discovery of these conserved properties has shaped our knowledge of the workings of protein kinases in general, and it has had important implications for our understanding of kinase dysregulation in disease and the development of effective kinase-targeted therapies.
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Affiliation(s)
- Neel H. Shah
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
- Department of Chemistry, University of California, Berkeley, CA, USA
- California Institute for Quantitative Biosciences, University of California, Berkeley, CA, USA
- Howard Hughes Medical Institute, University of California, Berkeley, CA, USA
| | - Jeanine F. Amacher
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
- Department of Chemistry, University of California, Berkeley, CA, USA
- California Institute for Quantitative Biosciences, University of California, Berkeley, CA, USA
- Howard Hughes Medical Institute, University of California, Berkeley, CA, USA
| | - Laura M. Nocka
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
- Department of Chemistry, University of California, Berkeley, CA, USA
- California Institute for Quantitative Biosciences, University of California, Berkeley, CA, USA
- Howard Hughes Medical Institute, University of California, Berkeley, CA, USA
| | - John Kuriyan
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
- Department of Chemistry, University of California, Berkeley, CA, USA
- California Institute for Quantitative Biosciences, University of California, Berkeley, CA, USA
- Howard Hughes Medical Institute, University of California, Berkeley, CA, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
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Moser R, Xu C, Kao M, Annis J, Lerma LA, Schaupp CM, Gurley KE, Jang IS, Biktasova A, Yarbrough WG, Margolin AA, Grandori C, Kemp CJ, Méndez E. Functional kinomics identifies candidate therapeutic targets in head and neck cancer. Clin Cancer Res 2015; 20:4274-88. [PMID: 25125259 DOI: 10.1158/1078-0432.ccr-13-2858] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
PURPOSE To identify novel therapeutic drug targets for p53-mutant head and neck squamous cell carcinoma (HNSCC). EXPERIMENTAL DESIGN RNAi kinome viability screens were performed on HNSCC cells, including autologous pairs from primary tumor and recurrent/metastatic lesions, and in parallel on murine squamous cell carcinoma (MSCC) cells derived from tumors of inbred mice bearing germline mutations in Trp53, and p53 regulatory genes: Atm, Prkdc, and p19(Arf). Cross-species analysis of cell lines stratified by p53 mutational status and metastatic phenotype was used to select 38 kinase targets. Both primary and secondary RNAi validation assays were performed on additional HNSCC cell lines to credential these kinase targets using multiple phenotypic endpoints. Kinase targets were also examined via chemical inhibition using a panel of kinase inhibitors. A preclinical study was conducted on the WEE1 kinase inhibitor, MK-1775. RESULTS Our functional kinomics approach identified novel survival kinases in HNSCC involved in G2-M cell-cycle checkpoint, SFK, PI3K, and FAK pathways. RNAi-mediated knockdown and chemical inhibition of the WEE1 kinase with a specific inhibitor, MK-1775, had a significant effect on both viability and apoptosis. Sensitivity to the MK-1775 kinase inhibitor is in part determined by p53 mutational status, and due to unscheduled mitotic entry. MK-1775 displays single-agent activity and potentiates the efficacy of cisplatin in a p53-mutant HNSCC xenograft model. CONCLUSIONS WEE1 kinase is a potential therapeutic drug target for HNSCC. This study supports the application of a functional kinomics strategy to identify novel therapeutic targets for cancer.
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Affiliation(s)
- Russell Moser
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Chang Xu
- Department of Otolaryngology: Head and Neck Surgery, University of Washington Medical Center, Seattle, Washington. Division of Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Michael Kao
- Department of Otolaryngology: Head and Neck Surgery, University of Washington Medical Center, Seattle, Washington
| | - James Annis
- Quellos High Throughput Facility, Institute for Stem Cell And Regenerative Medicine, University of Washington Medicine Research, Seattle, Washington
| | - Luisa Angelica Lerma
- Department of Otolaryngology: Head and Neck Surgery, University of Washington Medical Center, Seattle, Washington
| | - Christopher M Schaupp
- Toxicology Program, Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, Washington
| | - Kay E Gurley
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | | | - Asel Biktasova
- Deparment of Surgery, Otolaryngology: Head and Neck Surgery, Yale University School of Medicine, New Haven, Connecticut
| | - Wendell G Yarbrough
- Deparment of Surgery, Otolaryngology: Head and Neck Surgery, Yale University School of Medicine, New Haven, Connecticut
| | | | - Carla Grandori
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington. Quellos High Throughput Facility, Institute for Stem Cell And Regenerative Medicine, University of Washington Medicine Research, Seattle, Washington
| | - Christopher J Kemp
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, Washington.
| | - Eduardo Méndez
- Department of Otolaryngology: Head and Neck Surgery, University of Washington Medical Center, Seattle, Washington. Division of Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, Washington. Surgery and Perioperative Care Service, VA Puget Sound Health Care System, Seattle, Washington.
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Jung EJ, Park HB, Lee JB, Yoo CK, Kim BM, Kim HI, Cho IC, Lim HT. Genome-wide association study identifies quantitative trait loci affecting hematological traits in an F2 intercross between Landrace and Korean native pigs. Anim Genet 2014; 45:534-41. [PMID: 24797309 DOI: 10.1111/age.12175] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/19/2014] [Indexed: 11/30/2022]
Abstract
Changes affecting the status of health and robustness can bring about physiological alterations including hematological parameters in swine. To identify quantitative trait loci (QTL) associated with eight hematological traits (one leukocyte trait, six erythrocyte traits and one platelet trait), we conducted a genome-wide association study using the PorcineSNP60K BeadChip in a resource population derived from an intercross between Landrace and Korean native pigs. A total of 36 740 SNPs from 816 F2 progeny were analyzed for each blood-related trait after filtering for quality control. Data were analyzed by the genome-wide rapid association using mixed model and regression (GRAMMAR) approach. A total of 257 significant SNPs (P < 1.36 × 10(-6) ) on SSC3, 6, 8, 13 and 17 were identified for blood-related traits in this study. Interestingly, the genomic region between 17.9 and 130 Mb on SSC8 was found to be significantly associated with red blood cell, mean corpuscular volume and mean corpuscular hemoglobin. Our results include the identification of five significant SNPs within five candidate genes (KIT, IL15, TXK, ARAP2 and ERG) for hematopoiesis. Further validation of these identified SNPs could give valuable information for understanding the variation of hematological traits in pigs.
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Affiliation(s)
- E J Jung
- Department of Animal Science, College of Agriculture and Life Sciences, Gyeongsang National University, Jinju, 660-701, Korea; Institute of Agriculture and Life Sciences, Gyeongsang National University, Jinju, 660-701, Korea
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Maruyama T, Shimizu J, Suzuki N. T-cell protein tyrosine phosphatase (TCPTP) regulates phosphorylation of Txk, a tyrosine kinase of the Tec family. Inflamm Regen 2014. [DOI: 10.2492/inflammregen.34.240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Ryoo S, Choi J, Kim J, Bae S, Hong J, Jo S, Kim S, Lee Y. BIRB 796 has Distinctive Anti-inflammatory Effects on Different Cell Types. Immune Netw 2013; 13:283-8. [PMID: 24385947 PMCID: PMC3875787 DOI: 10.4110/in.2013.13.6.283] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Revised: 12/08/2013] [Accepted: 12/09/2013] [Indexed: 12/01/2022] Open
Abstract
The pro-inflammatory cytokines tumor necrosis factor-α (TNFα) and interleukin (IL)-1β are crucial mediators involved in chronic inflammatory diseases. Inflammatory signal pathways regulate inflammatory cytokine expression-mediated by p38 mitogen activated protein kinase (p38MAPK). Therefore, considerable attention has been given to p38MAPK as a target molecule for the development of a novel anti-inflammatory therapeutics. BIRB 796, one of p38MAPK inhibitor, is a candidate of therapeutic drug for chronic inflammatory diseases. In this study, we investigated the effect of BIRB 796 on inflammatory cytokine productions by lipopolysaccharide (LPS) in different immune cell types. BIRB 796 reduced LPS-mediated IL-8 production in THP-1 cells but not in Raw 264.7 cells. Further analysis of signal molecules by western blot revealed that BIRB 796 sufficiently suppressed LPS-mediated phosphorylation of p38MAPK in both cell types whereas it failed to block inhibitor of kappa B (I-κB) degradation in Raw 264.7 cells. Taken together, these results suggest that the anti-inflammatory function of BIRB 796 depends on cell types.
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Affiliation(s)
- Soyoon Ryoo
- Laboratory of Cytokine Immunology, Department of Biomedical Sciences and Technology, Konkuk University, Seoul 143-701, Korea. ; Division of Veterinary Bacterial Disease Division, Animal and Plant Quarantine Agency, Gyeonggi-do 480-757, Korea
| | - Jida Choi
- Laboratory of Cytokine Immunology, Department of Biomedical Sciences and Technology, Konkuk University, Seoul 143-701, Korea. ; Division of Veterinary Epidemiology, Animal and Plant Quarantine Agency, Gyeonggi-do 480-757, Korea
| | - Jaemyung Kim
- Division of Veterinary Bacterial Disease Division, Animal and Plant Quarantine Agency, Gyeonggi-do 480-757, Korea
| | - Suyoung Bae
- Laboratory of Cytokine Immunology, Department of Biomedical Sciences and Technology, Konkuk University, Seoul 143-701, Korea. ; Department of Bioequivalence Division for Drug Evaluation, Ministry of Food and Drug Safety, Chungcheongbuk-do 363-700, Korea
| | - Jaewoo Hong
- Laboratory of Cytokine Immunology, Department of Biomedical Sciences and Technology, Konkuk University, Seoul 143-701, Korea
| | - Seunghyun Jo
- Laboratory of Cytokine Immunology, Department of Biomedical Sciences and Technology, Konkuk University, Seoul 143-701, Korea
| | - Soohyun Kim
- Laboratory of Cytokine Immunology, Department of Biomedical Sciences and Technology, Konkuk University, Seoul 143-701, Korea
| | - Youngmin Lee
- Department of Medicine, Pusan Paik Hospital, Collage of Medicine, Inje University, Busan 633-165, Korea
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Affiliation(s)
- Jean-Damien Charrier
- Chemistry Department at Vertex Pharmaceuticals (Europe) Ltd, 86-88 Jubilee Avenue, Milton Park, Abingdon, Oxfordshire OX14 4RW, UK
| | - Ronald MA Knegtel
- Chemistry Department at Vertex Pharmaceuticals (Europe) Ltd, 86-88 Jubilee Avenue, Milton Park, Abingdon, Oxfordshire OX14 4RW, UK
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Cenni B, Gutmann S, Gottar-Guillier M. BMX and its role in inflammation, cardiovascular disease, and cancer. Int Rev Immunol 2012; 31:166-73. [PMID: 22449076 DOI: 10.3109/08830185.2012.663838] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Bone marrow kinase on chromosome X (BMX) is a cytosolic tyrosine kinase and a member of the TEC kinase family. BMX is expressed in hematopoietic cells of the myeloid lineage where it participates in the immune response. It is also involved in the response to ischemia and pressure overload in the endocardium and the cardiac endothelium. Moreover, BMX is expressed in several types of cancers and very recently has been shown to mediate the survival and tumorigenicity of glioblastoma cancer stem cells. In the inflammatory response BMX regulates the secretion of proinflammatory cytokines induced by TNFα, IL-1β, and TLR agonists. It is required for the activation of the MAP kinase and NFκB pathways and acts at the level of the essential TAK1/TAB complex. Cellular regulation of the IL-8 promoter by BMX is dependent on membrane localization mediated by its pleckstrin homology domain, as well as on BMX kinase activity. BMX deficiency confers protection from arthritis in a mouse model known to be dependent on macrophages and IL-1β. Genetic replacement of BMX with a kinase-inactive allele surprisingly restored susceptibility to arthritis, suggesting that in vivo BMX kinase activity can be dispensable. This review summarizes recent advances in the knowledge of BMX biology and their relevance for translational medicine.
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Affiliation(s)
- Bruno Cenni
- Novartis Institutes for BioMedical Research, Basel, Switzerland.
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Regulation of nucleocytoplasmic shuttling of Bruton's tyrosine kinase (Btk) through a novel SH3-dependent interaction with ankyrin repeat domain 54 (ANKRD54). Mol Cell Biol 2012; 32:2440-53. [PMID: 22527282 DOI: 10.1128/mcb.06620-11] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Bruton's tyrosine kinase (Btk), belonging to the Tec family of tyrosine kinases (TFKs), is essential for B-lymphocyte development. Abrogation of Btk signaling causes human X-linked agammaglobulinemia (XLA) and murine X-linked immunodeficiency (Xid). We employed affinity purification of Flag-tagged Btk, combined with tandem mass spectrometry, to capture and identify novel interacting proteins. We here characterize the interaction with ankryin repeat domain 54 protein (ANKRD54), also known as Lyn-interacting ankyrin repeat protein (Liar). While Btk is a nucleocytoplasmic protein, the Liar pool was found to shuttle at a higher rate than Btk. Importantly, our results suggest that Liar mediates nuclear export of both Btk and another TFK, Txk/Rlk. Liar-mediated Btk shuttling was enriched for activation loop, nonphosphorylated Btk and entirely dependent on Btk's SH3 domain. Liar also showed reduced binding to an aspartic acid phosphomimetic SH3 mutant. Three other investigated nucleus-located proteins, Abl, estrogen receptor β (ERβ), and transcription factor T-bet, were all unaffected by Liar. We mapped the interaction site to the C terminus of the Btk SH3 domain. A biotinylated, synthetic Btk peptide, ARDKNGQEGYIPSNYVTEAEDS, was sufficient for this interaction. Liar is the first protein identified that specifically influences the nucleocytoplasmic shuttling of Btk and Txk and belongs to a rare group of known proteins carrying out this activity in a Crm1-dependent manner.
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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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16
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Qi Q, Huang W, Bai Y, Balmus G, Weiss RS, August A. A unique role for ITK in survival of invariant NKT cells associated with the p53-dependent pathway in mice. THE JOURNAL OF IMMUNOLOGY 2012; 188:3611-9. [PMID: 22403441 DOI: 10.4049/jimmunol.1102475] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Invariant NKT (iNKT) cells play important roles in the immune response. ITK and TXK/RLK are Tec family kinases that are expressed in iNKT cells; the expression level of ITK is ∼7-fold higher than that of TXK. Itk(-/-) mice have reduced iNKT cell frequency and numbers, with defects in development and cytokine secretion that are exacerbated in Itk/Txk double-knockout mice. In contrast, there is no iNKT cell defect in Txk(-/-) mice. To determine whether ITK and TXK play distinct roles in iNKT cell development and function, we examined mice that overexpress TXK in T cells at levels similar to Itk. Overexpression of TXK rescues the maturation and cytokine secretion of Itk(-/-) iNKT cells, as well as altered expression of transcription factors T-bet, eomesodermin, and PLZF. In contrast, the increased apoptosis observed in Itk(-/-) splenic iNKT cells is not affected by TXK overexpression, likely due to the lack of effect on the elevated expression of p53 regulated proapoptotic pathways Fas, Bax, and Bad in those cells. Supporting this idea, p53(-/-) and Bax(-/-) mice have increased splenic iNKT cells. Our results suggest that TXK plays an overlapping role with ITK in iNKT cell development and function but that ITK also has a unique function in the survival of iNKT cells, likely via a p53-dependent pathway.
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Affiliation(s)
- Qian Qi
- Center for Molecular Immunology and Infectious Disease, The Pennsylvania State University, University Park, PA 16801, USA
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17
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Kannan Y, Wilson MS. TEC and MAPK Kinase Signalling Pathways in T helper (T H) cell Development, T H2 Differentiation and Allergic Asthma. JOURNAL OF CLINICAL & CELLULAR IMMUNOLOGY 2012; Suppl 12:11. [PMID: 24116341 PMCID: PMC3792371 DOI: 10.4172/2155-9899.s12-011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Significant advances in our understanding of the signalling events during T cell development and differentiation have been made in the past few decades. It is clear that ligation of the T cell receptor (TCR) triggers a series of proximal signalling cascades regulated by an array of protein kinases. These orchestrated and highly regulated series of events, with differential requirements of particular kinases, highlight the disparities between αβ+CD4+ T cells. Throughout this review we summarise both new and old studies, highlighting the role of Tec and MAPK in T cell development and differentiation with particular focus on T helper 2 (TH2) cells. Finally, as the allergy epidemic continues, we feature the role played by TH2 cells in the development of allergy and provide a brief update on promising kinase inhibitors that have been tested in vitro, in pre-clinical disease models in vivo and into clinical studies.
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Affiliation(s)
- Yashaswini Kannan
- Division of Molecular Immunology, National Institute for Medical Research, MRC, London, NW7 1AA, UK
| | - Mark S. Wilson
- Division of Molecular Immunology, National Institute for Medical Research, MRC, London, NW7 1AA, UK
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18
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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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19
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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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20
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Susaki K, Kitanaka A, Dobashi H, Kubota Y, Kittaka K, Kameda T, Yamaoka G, Mano H, Mihara K, Ishida T. Tec protein tyrosine kinase inhibits CD25 expression in human T-lymphocyte. Immunol Lett 2009; 127:135-42. [PMID: 19883687 DOI: 10.1016/j.imlet.2009.10.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2009] [Revised: 10/21/2009] [Accepted: 10/23/2009] [Indexed: 11/19/2022]
Abstract
The Tec protein tyrosine kinase (PTK) belongs to a group of structurally related nonreceptor PTKs that also includes Btk, Itk, Rlk, and Bmx. Previous studies have suggested that these kinases play important roles in hematopoiesis and in the lymphocyte signaling pathway. Despite evidence suggesting the involvement of Tec in the T-lymphocyte activation pathway via T-cell receptor (TCR) and CD28, Tec's role in T-lymphocytes remains unclear because of the lack of apparent defects in T-lymphocyte function in Tec-deficient mice. In this study, we investigated the role of Tec in human T-lymphocyte using the Jurkat T-lymphoid cell line stably transfected with a cDNA encoding Tec. We found that the expression of wild-type Tec inhibited the expression of CD25 induced by TCR cross-linking. Second, we observed that LFM-A13, a selective inhibitor of Tec family PTK, rescued the suppression of TCR-induced CD25 expression observed in wild-type Tec-expressing Jurkat cells. In addition, expression of kinase-deleted Tec did not alter the expression level of CD25 after TCR ligation. We conclude that Tec PTK mediates signals that negatively regulate CD25 expression induced by TCR cross-linking. This, in turn, implies that this PTK plays a role in the attenuation of IL-2 activity in human T-lymphocytes.
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Affiliation(s)
- Kentaro Susaki
- Division of Endocrinology and Metabolism, Hematology, Rheumatology, and Respiratory Medicine, Department of Internal Medicine, Faculty of Medicine, Kagawa University, 1750-1 Ikenobe, Miki-cho, Kita-gun, Kagawa 761-0793, Japan
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21
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Readinger JA, Mueller KL, Venegas AM, Horai R, Schwartzberg PL. Tec kinases regulate T-lymphocyte development and function: new insights into the roles of Itk and Rlk/Txk. Immunol Rev 2009; 228:93-114. [PMID: 19290923 DOI: 10.1111/j.1600-065x.2008.00757.x] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The Tec (tyrosine kinase expressed in hepatocellular carcinoma) family of non-receptor tyrosine kinases consists of five members: Tec, Bruton's tyrosine kinase (Btk), inducible T-cell kinase (Itk), resting lymphocyte kinase (Rlk/Txk), and bone marrow-expressed kinase (Bmx/Etk). Although their functions are probably best understood in antigen receptor signaling, where they participate in the phosphorylation and regulation of phospholipase C-gamma (PLC-gamma), it is now appreciated that these kinases contribute to signaling from many receptors and that they participate in multiple downstream pathways, including regulation of the actin cytoskeleton. In T cells, three Tec kinases are expressed, Itk, Rlk/Txk, and Tec. Itk is expressed at highest amounts and plays the major role in regulating signaling from the T-cell receptor. Recent studies provide evidence that these kinases contribute to multiple aspects of T-cell biology and have unique roles in T-cell development that have revealed new insight into the regulation of conventional and innate T-cell development. We review new findings on the Tec kinases with a focus on their roles in T-cell development and mature T-cell differentiation.
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Affiliation(s)
- Julie A Readinger
- National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
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22
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Conley ME, Dobbs AK, Farmer DM, Kilic S, Paris K, Grigoriadou S, Coustan-Smith E, Howard V, Campana D. Primary B cell immunodeficiencies: comparisons and contrasts. Annu Rev Immunol 2009; 27:199-227. [PMID: 19302039 DOI: 10.1146/annurev.immunol.021908.132649] [Citation(s) in RCA: 281] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Sophisticated genetic tools have made possible the identification of the genes responsible for most well-described immunodeficiencies in the past 15 years. Mutations in Btk, components of the pre-B cell and B cell receptor (lambda5, Igalpha, Igbeta), or the scaffold protein BLNK account for approximately 90% of patients with defects in early B cell development. Hyper-IgM syndromes result from mutations in CD40 ligand, CD40, AID, or UNG in 70-80% of affected patients. Rare defects in ICOS or CD19 can result in a clinical picture that is consistent with common variable immunodeficiency, and as many as 10% of patients with this disorder have heterozygous amino acid substitutions in TACI. For all these disorders, there is considerable clinical heterogeneity in patients with the same mutation. Identifying the genetic and environmental factors that influence the clinical phenotype may enhance patient care and our understanding of normal B cell development.
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Affiliation(s)
- Mary Ellen Conley
- Department of Pediatrics, University of Tennessee College of Medicine, Memphis, Tennessee 38163, USA.
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23
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Sahu N, Venegas AM, Jankovic D, Mitzner W, Gomez-Rodriguez J, Cannons JL, Sommers C, Love P, Sher A, Schwartzberg PL, August A. Selective expression rather than specific function of Txk and Itk regulate Th1 and Th2 responses. THE JOURNAL OF IMMUNOLOGY 2009; 181:6125-31. [PMID: 18941202 DOI: 10.4049/jimmunol.181.9.6125] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Itk and Txk/Rlk are Tec family kinases expressed in T cells. Itk is expressed in both Th1 and Th2 cells. By contrast, Txk is preferentially expressed in Th1 cells. Although Itk is required for Th2 responses in vivo and Txk is suggested to regulate IFN-gamma expression and Th1 responses, it remains unclear whether these kinases have distinct roles in Th cell differentiation/function. We demonstrate here that Txk-null CD4(+) T cells are capable of producing both Th1 and Th2 cytokines similar to those produced by wild-type CD4(+) T cells. To further examine whether Itk and Txk play distinct roles in Th cell differentiation and function, we examined Itk-null mice carrying a transgene that expresses Txk at levels similar to the expression of Itk in Th2 cells. Using two Th2 model systems, allergic asthma and schistosome egg-induced lung granulomas, we found that the Txk transgene rescued Th2 cytokine production and all Th2 symptoms without notable enhancement of IFN-gamma expression. These results suggest that Txk is not a specific regulator of Th1 responses. Importantly, they suggest that Itk and Txk exert their effects on Th cell differentiation/function at the level of expression.
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Affiliation(s)
- Nisebita Sahu
- Center for Molecular Immunology and Infectious Disease and Department of Veterinary and Biomedical Sciences, Pennsylvania State University, University Park, PA 16802, USA
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24
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Gomez-Rodriguez J, Readinger JA, Viorritto IC, Mueller KL, Houghtling RA, Schwartzberg PL. Tec kinases, actin, and cell adhesion. Immunol Rev 2007; 218:45-64. [PMID: 17624943 DOI: 10.1111/j.1600-065x.2007.00534.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The Tec family non-receptor tyrosine kinases have been recognized for their roles in the regulation of phospholipase C-gamma and Ca(2+) mobilization downstream from antigen receptors on lymphocytes. Recent data, however, show that the Tec family kinase interleukin-2-inducible T-cell kinase (Itk) also participates in pathways regulating the actin cytoskeleton and 'inside-out' signaling to integrins downstream from the T-cell antigen receptor. Data suggest that Itk may function in a kinase-independent fashion to regulate proper recruitment of the Vav1 guanine nucleotide exchange factor. By enhancing actin cytoskeleton reorganization, recruitment of signaling molecules to the immune synapse, and integrin clustering in response to both antigen and chemokine receptors, the Tec kinases serve as modulators or amplifiers that can increase the duration of T-cell signaling and regulate T-cell functional responses.
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Affiliation(s)
- Julio Gomez-Rodriguez
- National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
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25
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Abstract
The Tec family of tyrosine kinases consists of five members (Itk, Rlk, Tec, Btk, and Bmx) that are expressed predominantly in hematopoietic cells. The exceptions, Tec and Bmx, are also found in endothelial cells. Tec kinases constitute the second largest family of cytoplasmic protein tyrosine kinases. While B cells express Btk and Tec, and T cells express Itk, Rlk, and Tec, all four of these kinases (Btk, Itk, Rlk, and Tec) can be detected in mast cells. This chapter will focus on the biochemical and cell biological data that have been accumulated regarding Itk, Rlk, Btk, and Tec. In particular, distinctions between the different Tec kinase family members will be highlighted, with a goal of providing insight into the unique functions of each kinase. The known functions of Tec kinases in T cell and mast cell signaling will then be described, with a particular focus on T cell receptor and mast cell Fc epsilon RI signaling pathways.
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Affiliation(s)
- Martin Felices
- Department of Pathology, University of Massachusetts Medical School, Massachusetts, USA
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26
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Hughes-Fulford M, Rodenacker K, Jütting U. Reduction of anabolic signals and alteration of osteoblast nuclear morphology in microgravity. J Cell Biochem 2006; 99:435-49. [PMID: 16619267 DOI: 10.1002/jcb.20883] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Bone loss has been repeatedly documented in astronauts after flight, yet little is known about the mechanism of bone loss in space flight. Osteoblasts were activated during space flight in microgravity (microg) with and without a 1 gravity (1 g) field and 24 genes were analyzed for early induction. Induction of proliferating cell nuclear antigen (PCNA), transforming growth factor beta (TGFbeta), cyclo-oxygenase-2 (cox-2), cpla2, osteocalcin (OC), c-myc, fibroblast growth factor-2 (fgf-2), bcl2, bax, and fgf-2 message as well as FGF-2 protein were significantly depressed in microg when compared to ground (gr). Artificial onboard gravity normalized the induction of c-myc, cox-2, TGFbeta, bax, bcl2, and fgf-2 message as well as FGF-2 protein synthesis in spaceflight samples. In normal gravity, FGF-2 induces bcl2 expression; we found that bcl2 expression was significantly reduced in microgravity conditions. Since nuclear shape is known to elongate in the absence of mitogens like FGF-2, we used high-resolution image-based morphometry to characterize changes in osteoblast nuclear architecture under microgravity, 1 g flight, and ground conditions. Besides changes in cell shape (roundish/elliptic), other high-resolution analyses show clear influences of gravity on the inner nuclear structure. These changes occur in the texture, arrangement, and contrast of nuclear particles and mathematical modeling defines the single cell classification of the osteoblasts. Changes in nuclear structure were evident as early as 24 h after exposure to microgravity. This documented alteration in nuclear architecture may be a direct result of decreased expression of autocrine and cell cycle genes, suggesting an inhibition of anabolic response in microg. Life on this planet has evolved in a normal gravity field and these data suggest that gravity plays a significant role in regulation of osteoblast transcription.
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Affiliation(s)
- Millie Hughes-Fulford
- Northern California Institute for Research and Education, San Francisco, California, USA.
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27
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Garçon F, Nunès JA. Travel informations on the Tec kinases during lymphocyte activation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2006; 584:15-27. [PMID: 16802596 DOI: 10.1007/0-387-34132-3_2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Affiliation(s)
- Fabien Garçon
- Laboratory of Lymphocyte Signalling and Development, Babraham Institute, Babraham Research Campus, Cambridge CB2 4AT, UK
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28
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Kosaka Y, Felices M, Berg LJ. Itk and Th2 responses: action but no reaction. Trends Immunol 2006; 27:453-60. [PMID: 16931156 DOI: 10.1016/j.it.2006.08.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2006] [Revised: 07/14/2006] [Accepted: 08/09/2006] [Indexed: 01/16/2023]
Abstract
The Tec family tyrosine kinase, Itk, was initially characterized as a crucial component of T-cell receptor signaling pathways resulting in phospholipase C-gamma1 activation and actin polymerization. In 1999, a seminal report by Fowell, Locksley and colleagues demonstrated that, in CD4+ T cells, Itk-dependent signals are differentially required for T-helper (Th)2 versus Th1 differentiation and effector function. These findings launched a series of in vitro and in vivo studies addressing the molecular defects of Itk-/- CD4+ T cells, and the impaired immune responses of intact Itk-deficient mice. While demonstrating a bias against Th2 differentiation, overall these experiments have indicated that the most significant failing is an inability of Itk-/- CD4+ T cells to produce Th2 cytokines in a recall response, rather than an absolute defect in Th2 differentiation by T cells lacking Itk. In this review, we discuss the pathways by which Itk might impact the differentiation of Th cells.
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Affiliation(s)
- Yoko Kosaka
- Department of Pathology, University of Massachusetts Medical School, Worcester, MA 01655, USA
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29
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Barbee SD, Alberola-Ila J. Phosphatidylinositol 3-kinase improves the efficiency of positive selection. Int Immunol 2006; 18:921-30. [PMID: 16636016 DOI: 10.1093/intimm/dxl027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We have generated transgenic mice expressing the amino-terminal fragment of the phosphatidylinositol 3-kinase (PI3K) catalytic subunit (p110ABD) in thymocytes. Expression of p110ABD results in constitutive activation of PI3K and in significant increases in the numbers of mature, single-positive thymocytes. We previously reported that the increase in mature cells was in part due to a defect in thymic emigration. In this study we identify another component to this phenotype. Expression of p110ABD results in an enhancement of positive selection, without alterations in thymocyte lifespan or negative selection. Since PI3K can affect activation of Btk, which in turn potentiates calcium fluxes, during B cell development, our results suggest that PI3K could play a role in the regulation of Itk kinases in T cells, and that both cell types share a common signaling network to modulate calcium responses downstream of their antigen receptor.
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Affiliation(s)
- Susannah D Barbee
- Division of Biology, California Institute of Technology, 1200 E. California Boulevard, Mail code 147-75, Pasadena, CA 91125, USA
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30
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Conley ME, Broides A, Hernandez-Trujillo V, Howard V, Kanegane H, Miyawaki T, Shurtleff SA. Genetic analysis of patients with defects in early B-cell development. Immunol Rev 2005; 203:216-34. [PMID: 15661032 DOI: 10.1111/j.0105-2896.2005.00233.x] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Approximately 85% of patients with defects in early B-cell development have X-linked agammaglobulinemia (XLA), a disorder caused by mutations in the cytoplasmic Bruton's tyrosine kinase (Btk). Although Btk is activated by cross-linking of a variety of cell-surface receptors, the most critical signal transduction pathway is the one initiated by the pre-B cell and B-cell antigen receptor complex. Mutations in Btk are highly diverse, and no single mutation accounts for more than 3% of patients. Although there is no strong genotype/phenotype correlation in XLA, the specific mutation in Btk is one of the factors that influences the severity of disease. Mutations in the components of the pre-B cell and B-cell antigen receptor complex account for an additional 5-7% of patients with defects in early B-cell development. Patients with defects in these proteins are clinically indistinguishable from those with XLA. However, they tend to be younger at the time of diagnosis, and whereas most patients with XLA have a small number of B cells in the peripheral circulation, these cells are not found in patients with defects in micro heavy chain or Igalpha. Polymorphic variants in the components of the pre-B cell and B-cell receptor complex, particularly micro heavy chain and lambda5, may contribute to the severity of XLA.
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Affiliation(s)
- Mary Ellen Conley
- Department of Pediatrics, University of Tennessee College of Medicine, Memphis, TN 38105, USA.
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31
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Schwartzberg PL, Finkelstein LD, Readinger JA. TEC-family kinases: regulators of T-helper-cell differentiation. Nat Rev Immunol 2005; 5:284-95. [PMID: 15803148 DOI: 10.1038/nri1591] [Citation(s) in RCA: 120] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The TEC-family protein tyrosine kinases ITK, RLK and TEC have been identified as key components of T-cell-receptor signalling that contribute to the regulation of phospholipase C-gamma, the mobilization of Ca(2+) and the activation of mitogen-activated protein kinases. Recent data also show that TEC kinases contribute to T-cell-receptor-driven actin reorganization and cell polarization, which are required for productive T-cell activation. Functional studies have implicated TEC kinases as important mediators of pathways that control the differentiation of CD4(+) T helper cells. Here, we review studies of signalling pathways that involve TEC kinases and how these pathways might contribute to the regulation of T-helper-cell differentiation and function.
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Affiliation(s)
- Pamela L Schwartzberg
- National Human Genome Research Institute, National Institutes of Health, 4A38/49 Convent Drive, Bethesda, Maryland 20892, USA.
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32
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Abstract
The Tec family tyrosine kinases are now recognized as important mediators of antigen receptor signaling in lymphocytes. Three members of this family, Itk, Rlk, and Tec, are expressed in T cells and activated in response to T cell receptor (TCR) engagement. Although initial studies demonstrated a role for these proteins in TCR-mediated activation of phospholipase C-gamma, recent data indicate that Tec family kinases also regulate actin cytoskeletal reorganization and cellular adhesion following TCR stimulation. In addition, Tec family kinases are activated downstream of G protein-coupled chemokine receptors, where they play parallel roles in the regulation of Rho GTPases, cell polarization, adhesion, and migration. In all these systems, however, Tec family kinases are not essential signaling components, but instead function to modulate or amplify signaling pathways. Although they quantitatively reduce proximal signaling, mutations that eliminate Tec family kinases in T cells nonetheless qualitatively alter T cell development and differentiation.
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Affiliation(s)
- Leslie J Berg
- Department of Pathology, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA.
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33
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Barbee SD, Alberola-Ila J. Phosphatidylinositol 3-Kinase Regulates Thymic Exit. THE JOURNAL OF IMMUNOLOGY 2005; 174:1230-8. [PMID: 15661877 DOI: 10.4049/jimmunol.174.3.1230] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
To understand the role of PI3K during T cell development, we generated transgenic mice expressing the N terminus of the PI3K catalytic subunit (p110(ABD); ABD, adaptor binding domain) in thymocytes. Expression of p110(ABD) activates endogenous p110 and results in the accumulation of mature single-positive CD3(high)heat-stable Ag(low) thymocytes. This is mostly due to a defect in emigration of those cells, as shown by the delayed appearance of peripheral T cells in neonatal transgenic mice and by competitive adoptive transfer experiments. Although the mechanisms underlying these effects of PI3K are not yet clear, our results show an important role for PI3K activity in the regulation of mature thymocyte exit to the periphery.
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Affiliation(s)
- Susannah D Barbee
- Division of Biology, California Institute of Technology, Pasadena, CA 91125, USA
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34
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Takesono A, Horai R, Mandai M, Dombroski D, Schwartzberg PL. Requirement for Tec kinases in chemokine-induced migration and activation of Cdc42 and Rac. Curr Biol 2004; 14:917-22. [PMID: 15186750 DOI: 10.1016/j.cub.2004.04.011] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2003] [Revised: 03/09/2004] [Accepted: 03/30/2004] [Indexed: 11/29/2022]
Abstract
Cell polarization and migration in response to chemokines is essential for proper development of the immune system and activation of immune responses. Recent studies of chemokine signaling have revealed a critical role for PI3-Kinase, which is required for polarized membrane association of pleckstrin homology (PH) domain-containing proteins and activation of Rho family GTPases that are essential for cell polarization and actin reorganization. Additional data argue that tyrosine kinases are also important for chemokine-induced Rac activation. However, how and which kinases participate in these pathways remain unclear. We demonstrate here that the Tec kinases Itk and Rlk play an important role in chemokine signaling in T lymphocytes. Chemokine stimulation induced transient membrane association of Itk and phosphorylation of both Itk and Rlk, and purified T cells from Rlk(-/-)Itk(-/-) mice exhibited defective migration to multiple chemokines in vitro and decreased homing to lymph nodes upon transfer to wt mice. Expression of a dominant-negative Itk impaired SDF-1alpha-induced migration, cell polarization, and activation of Rac and Cdc42. Thus, Tec kinases are critical components of signaling pathways required for actin polarization downstream from both antigen and chemokine receptors in T cells.
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Affiliation(s)
- Aya Takesono
- National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
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35
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Rafalska I, Zhang Z, Benderska N, Wolff H, Hartmann AM, Brack-Werner R, Stamm S. The intranuclear localization and function of YT521-B is regulated by tyrosine phosphorylation. Hum Mol Genet 2004; 13:1535-49. [PMID: 15175272 DOI: 10.1093/hmg/ddh167] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
YT521-B is a ubiquitously expressed nuclear protein that changes alternative splice site usage in a concentration dependent manner. YT521-B is located in a dynamic nuclear compartment, the YT body. We show that YT521-B is tyrosine phosphorylated by c-Abl in the nucleus. The protein shuttles between nucleus and cytosol, where it can be phosphorylated by c-Src or p59(fyn). Tyrosine phosphorylation causes dispersion of YT521-B from YT bodies to the nucleoplasm. Whereas YT bodies are soluble in non-denaturing buffers, the phosphorylated, dispersed form is non-soluble. Non-phosphorylated YT521-B changes alternative splice site selection of the IL-4 receptor, CD44 and SRp20, but phosphorylation of c-Abl minimizes this concentration dependent effect. We propose that tyrosine phosphorylation causes sequestration of YT521-B in an insoluble nuclear form, which abolishes the ability of YT521-B to change alternative splice sites.
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Affiliation(s)
- Ilona Rafalska
- University of Erlangen, Institute for Biochemistry, Germany
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36
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Schwartzberg PL. Genetic approaches to tyrosine kinase signaling pathways in the immune system. Immunol Res 2004; 27:481-8. [PMID: 12857991 DOI: 10.1385/ir:27:2-3:481] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The development of a productive immune response requires the carefully coordinated activation of lymphocytes through their cell-surface antigen receptors, surface immunoglobulin (Ig) on B cells and the T cell receptor (TCR) on T cells. Studies of mutant cell lines, gene-targeted mice and humans with inherited immunodeficiencies have demonstrated that tyrosine kinases are critical components of lymphocyte antigen-receptor-signaling pathways. Our laboratory is interested in the mechanisms by which modulation of signaling pathways involving tyrosine kinases and related signaling molecules can influence cell function and development. We have concentrated our attention on the genetic and biochemical dissection of signaling pathways in the immune system, and how altering these pathways can change responses to infectious disease. As a model system, we are examining the Tec family kinases and their roles in T lymphocyte development and function.
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Affiliation(s)
- Pamela L Schwartzberg
- Genetic Disease Research Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892-4472, USA.
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Abstract
The T helper lymphocyte is responsible for orchestrating the appropriate immune response to a wide variety of pathogens. The recognition of the polarized T helper cell subsets Th1 and Th2 has led to an understanding of the role of these cells in coordinating a variety of immune responses, both in responses to pathogens and in autoimmune and allergic disease. Here, we discuss the mechanisms that control lineage commitment to the Th1 phenotype. What has recently emerged is a rich understanding of the cytokines, receptors, signal transduction pathways, and transcription factors involved in Th1 differentiation. Although the picture is still incomplete, the basic pathways leading to Th1 differentiation can now be understood in in vitro and a number of infection and disease models.
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Affiliation(s)
- Susanne J Szabo
- Department of Immunology and Infectious Diseases, Harvard School of Public Health Boston, Massachusetts 02115, USA.
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38
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Chen CH, Seguin-Devaux C, Burke NA, Oriss TB, Watkins SC, Clipstone N, Ray A. Transforming growth factor beta blocks Tec kinase phosphorylation, Ca2+ influx, and NFATc translocation causing inhibition of T cell differentiation. J Exp Med 2003. [PMID: 12810687 DOI: 10.1084/jem.20021170.pmid:12810687;pmcid:pmc2193945] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/09/2023] Open
Abstract
Transforming growth factor (TGF)-beta inhibits T cell proliferation and differentiation. TGF-beta has been shown to inhibit the expression of transcription factors such as GATA-3 and T-bet that play important roles in T cell differentiation. Here we show that TGF-beta inhibits T cell differentiation at a more proximal step. An early event during T cell activation is increased intracellular calcium levels. Calcium influx in activated T cells and the subsequent activation of transcription factors such as NFATc, events essential for T cell differentiation, are modulated by the Tec kinases that are downstream of the T cell receptor and CD28. We show that in stimulated CD4+ T cells, TGF-beta inhibits phosphorylation and activation of the Tec kinase Itk, increase in intracellular Ca2+ levels, NFATc translocation, and activation of the mitogen-activated protein kinase ERK that together regulate T cell differentiation. Our studies suggest that by inhibiting Itk, and consequently Ca2+ influx, TGF-beta limits T cell differentiation along both the Th1 and Th2 lineages.
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Affiliation(s)
- Chang-Hung Chen
- Vion Pharmaceuticals, Incorporated, New Haven, CT 06511, USA
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39
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Chen CH, Seguin-Devaux C, Burke NA, Oriss TB, Watkins SC, Clipstone N, Ray A. Transforming growth factor beta blocks Tec kinase phosphorylation, Ca2+ influx, and NFATc translocation causing inhibition of T cell differentiation. J Exp Med 2003; 197:1689-99. [PMID: 12810687 PMCID: PMC2193945 DOI: 10.1084/jem.20021170] [Citation(s) in RCA: 123] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Transforming growth factor (TGF)-beta inhibits T cell proliferation and differentiation. TGF-beta has been shown to inhibit the expression of transcription factors such as GATA-3 and T-bet that play important roles in T cell differentiation. Here we show that TGF-beta inhibits T cell differentiation at a more proximal step. An early event during T cell activation is increased intracellular calcium levels. Calcium influx in activated T cells and the subsequent activation of transcription factors such as NFATc, events essential for T cell differentiation, are modulated by the Tec kinases that are downstream of the T cell receptor and CD28. We show that in stimulated CD4+ T cells, TGF-beta inhibits phosphorylation and activation of the Tec kinase Itk, increase in intracellular Ca2+ levels, NFATc translocation, and activation of the mitogen-activated protein kinase ERK that together regulate T cell differentiation. Our studies suggest that by inhibiting Itk, and consequently Ca2+ influx, TGF-beta limits T cell differentiation along both the Th1 and Th2 lineages.
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Affiliation(s)
- Chang-Hung Chen
- Vion Pharmaceuticals, Incorporated, New Haven, CT 06511, USA
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40
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Ahn BH, Kim SY, Kim EH, Choi KS, Kwon TK, Lee YH, Chang JS, Kim MS, Jo YH, Min DS. Transmodulation between phospholipase D and c-Src enhances cell proliferation. Mol Cell Biol 2003; 23:3103-15. [PMID: 12697812 PMCID: PMC153190 DOI: 10.1128/mcb.23.9.3103-3115.2003] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Phospholipase D (PLD) has been implicated in the signal transduction pathways initiated by several mitogenic protein tyrosine kinases. We demonstrate for the first time that most notably PLD2 and to a lesser extent the PLD1 isoform are tyrosine phosphorylated by c-Src tyrosine kinase via direct association. Moreover, epidermal growth factor induced tyrosine phosphorylation of PLD2 and its interaction with c-Src in A431 cells. Interaction between these proteins is via the pleckstrin homology domain of PLD2 and the catalytic domain of c-Src. Coexpression of PLD1 or PLD2 with c-Src synergistically enhances cellular proliferation compared with expression of either molecule. While PLD activity as a lipid-hydrolyzing enzyme is not affected by c-Src, wild-type PLDs but not catalytically inactive PLD mutants significantly increase c-Src kinase activity, up-regulating c-Src-mediated paxillin phosphorylation and extracellular signal-regulated kinase activity. These results demonstrate the critical role of PLD catalytic activity in the stimulation of Src signaling. In conclusion, we provide the first evidence that c-Src acts as a kinase of PLD and PLD acts as an activator of c-Src. This transmodulation between c-Src and PLD may contribute to the promotion of cellular proliferation via amplification of mitogenic signaling pathways.
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Affiliation(s)
- Bong-Hyun Ahn
- Department of Physiology, College of Medicine, The Catholic University of Korea, Seoul, Korea
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41
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Nore BF, Mattsson PT, Antonsson P, Bäckesjö CM, Westlund A, Lennartsson J, Hansson H, Löw P, Rönnstrand L, Smith CIE. Identification of phosphorylation sites within the SH3 domains of Tec family tyrosine kinases. BIOCHIMICA ET BIOPHYSICA ACTA 2003; 1645:123-32. [PMID: 12573241 DOI: 10.1016/s1570-9639(02)00524-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Tec family protein tyrosine kinases (TFKs) play a central role in hematopoietic cellular signaling. Initial activation takes place through specific tyrosine phosphorylation situated in the activation loop. Further activation occurs within the SH3 domain via a transphosphorylation mechanism, which for Bruton's tyrosine kinase (Btk) affects tyrosine 223. We found that TFKs phosphorylate preferentially their own SH3 domains, but differentially phosphorylate other member family SH3 domains, whereas non-related SH3 domains are not phosphorylated. We demonstrate that SH3 domains are good and reliable substrates. We observe that transphosphorylation is selective not only for SH3 domains, but also for dual SH3SH2 domains. However, the dual domain is phosphorylated more effectively. The major phosphorylation sites were identified as conserved tyrosines, for Itk Y180 and for Bmx Y215, both sites being homologous to the Y223 site in Btk. There is, however, one exception because the Tec-SH3 domain is phosphorylated at a non-homologous site, nevertheless a conserved tyrosine, Y206. Consistent with these findings, the 3D structures for SH3 domains point out that these phosphorylated tyrosines are located on the ligand-binding surface. Because a number of Tec family kinases are coexpressed in cells, it is possible that they could regulate the activity of each other through transphosphorylation.
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Affiliation(s)
- Beston F Nore
- Karolinska Institutet, Clinical Research Center (CRC) at Novum, Huddinge University Hospital, SE-141 86, Huddinge, Sweden.
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42
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Abstract
Selection of the translational initiation site in most eukaryotic mRNAs appears to occur via a scanning mechanism which predicts that proximity to the 5' end plays a dominant role in identifying the start codon. This "position effect" is seen in cases where a mutation creates an AUG codon upstream from the normal start site and translation shifts to the upstream site. The position effect is evident also in cases where a silent internal AUG codon is activated upon being relocated closer to the 5' end. Two mechanisms for escaping the first-AUG rule--reinitiation and context-dependent leaky scanning--enable downstream AUG codons to be accessed in some mRNAs. Although these mechanisms are not new, many new examples of their use have emerged. Via these escape pathways, the scanning mechanism operates even in extreme cases, such as a plant virus mRNA in which translation initiates from three start sites over a distance of 900 nt. This depends on careful structural arrangements, however, which are rarely present in cellular mRNAs. Understanding the rules for initiation of translation enables understanding of human diseases in which the expression of a critical gene is reduced by mutations that add upstream AUG codons or change the context around the AUG(START) codon. The opposite problem occurs in the case of hereditary thrombocythemia: translational efficiency is increased by mutations that remove or restructure a small upstream open reading frame in thrombopoietin mRNA, and the resulting overproduction of the cytokine causes the disease. This and other examples support the idea that 5' leader sequences are sometimes structured deliberately in a way that constrains scanning in order to prevent harmful overproduction of potent regulatory proteins. The accumulated evidence reveals how the scanning mechanism dictates the pattern of transcription--forcing production of monocistronic mRNAs--and the pattern of translation of eukaryotic cellular and viral genes.
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Key Words
- translational control
- aug context
- 5′ untranslated region
- reinitiation
- leaky scanning
- dicistronic mrna
- internal ribosome entry site
- adometdc, s-adenosylmethionine decarboxylase
- a2ar, a2a adenosine receptor
- c/ebp, ccaat/enhancer binding protein
- ctl, cytotoxic t-lymphocyte
- egfp, enhanced green fluorescent protein
- eif, eukaryotic initiation factor
- hiv-1, human immunodeficiency virus 1
- ires, internal ribosome entry site
- lef1, lymphoid enhancer factor-1
- ogp, osteogenic growth peptide
- orf, open reading frame
- r, purine
- tpo, thrombopoietin
- uporf, upstream open reading frame
- utr, untranslated region
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Affiliation(s)
- Marilyn Kozak
- Department of Biochemistry, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, 675 Hoes Lane, Piscataway, NJ 08854, USA.
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43
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Abstract
Inducible T-cell kinase (ITK) is a member of the Tec family of tyrosine kinases that are involved in signals emanating from cytokine receptors, antigen receptors and other lymphoid cell surface receptors. Stimulation of tyrosine phosphorylation and activation of ITK by the T-cell antigen receptor, CD28 and CD2 requires the presence of the Src family kinase Lck in T-cells. We have previously demonstrated that the activation of ITK by Src family kinases uses a phosphatidylinositol 3-kinase pathway, which recruits ITK to the membrane via its pleckstrin homology (PH) domain where it is acted upon by Src. We have further explored the mechanism of this requirement for Src family kinases in the activation of ITK. We found that deletion of the proline rich sequence found in the Tec homology domain of ITK results in reduced basal activity of ITK approximately 50%. These differences in the basal activity of ITK were observed when the PH domain was deleted or when the kinase was membrane targeted. Furthermore, this deletion reduces the ability of the Src family kinase Lck to activate ITK, as well as to induce the ITK mediated tyrosine phosphorylation of its substrate PLCgamma1. By contrast, deletion of the SH3 domain of ITK resulted in a two-fold increase in the basal activity of ITK, and allowed this mutant to have an enhanced response to Lck. These results suggest that the proline rich region within the Tec homology domain of ITK regulates its basal activity and its response to Src family kinase signals.
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Affiliation(s)
- Shengli Hao
- Immunology Research Laboratories and Department of Veterinary Science, The Pennsylvania State University, 115 Henning Building, University Park, PA 16802, USA
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44
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Takesono A, Finkelstein LD, Schwartzberg PL. Beyond calcium: new signaling pathways for Tec family kinases. J Cell Sci 2002; 115:3039-48. [PMID: 12118060 DOI: 10.1242/jcs.115.15.3039] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The Tec kinases represent the second largest family of mammalian non-receptor tyrosine kinases and are distinguished by the presence of distinct proline-rich regions and pleckstrin homology domains that are required for proper regulation and activation. Best studied in lymphocyte and mast cells, these kinases are critical for the full activation of phospholipase-C γ (PLC-γ) and Ca2+ mobilization downstream of antigen receptors. However, it has become increasingly clear that these kinases are activated downstream of many cell-surface receptors,including receptor tyrosine kinases, cytokine receptors, integrins and G-protein-coupled receptors. Evidence suggests that the Tec kinases influence a wide range of signaling pathways controlling activation of MAP kinases,actin reorganization, transcriptional regulation, cell survival and cellular transformation. Their impact on cellular physiology suggests that the Tec kinases help regulate multiple cellular processes beyond Ca2+mobilization.
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Affiliation(s)
- Aya Takesono
- National Human Genome Research Institute, 49 Convent Drive, 49/4A38, National Institutes of Health, Bethesda, MD 20892, USA
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45
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Miller AT, Berg LJ. New insights into the regulation and functions of Tec family tyrosine kinases in the immune system. Curr Opin Immunol 2002; 14:331-40. [PMID: 11973131 DOI: 10.1016/s0952-7915(02)00345-x] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The Tec family of protein tyrosine kinases play an important role in signaling through antigen-receptors such as the TCR, BCR and Fcepsilon receptor. Recent studies have generated new insights into the domains in Tec kinases that take part in intramolecular and intermolecular binding. Furthermore, the consequences of these domain interactions for Tec activation and downregulation have been better defined. Genetic studies of kinase-knockout mice have emphasized the importance of Tec kinases in lymphocyte development, differentiation and apoptosis.
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Affiliation(s)
- Andrew T Miller
- Department of Pathology and Program in Immunology and Virology, University of Massachusetts Medical Center, Worcester, MA 01655, USA
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46
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Takeba Y, Nagafuchi H, Takeno M, Kashiwakura JI, Suzuki N. Txk, a member of nonreceptor tyrosine kinase of Tec family, acts as a Th1 cell-specific transcription factor and regulates IFN-gamma gene transcription. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2002; 168:2365-70. [PMID: 11859127 DOI: 10.4049/jimmunol.168.5.2365] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Precise mechanisms responsible for Th1 cell activation and differentiation are not fully elucidated. We have recently reported that Txk, a member of Tec family nonreceptor tyrosine kinase, is expressed on Th1/Th0 cells, and Txk regulates specifically IFN-gamma gene expression. In this study, we found that Txk bound to IFN-gamma promoter region. Txk transfection increased transcriptional activity of IFN-gamma promoter plus luciferase constructs severalfold, including IFN-gamma promoter -538, -208, and -53. IFN-gamma promoter -39 was refractory to the Txk transfection. The actual site to which Txk bound was the element consisting of -53 and -39 bp from the transcription start site of human IFN-gamma gene, a site distinct from several previously characterized binding sites. We found that the entire -53/-39 region was necessary for the binding to and function of Txk, because mutant promoter oligoDNA that contained contiguous five base substitutions dispersed throughout the -53/-39 inhibited the binding, and the mutant promoters did not respond to the Txk transfection. Similar sequences of this element are found within the 5' flanking regions of several Th1 cell-associated protein genes. Thus, Txk is expressed on Th1/Th0 cells with the IFN-gamma production and acts as a Th1 cell-specific transcription factor.
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Affiliation(s)
- Yuko Takeba
- Department of Immunology and Medicine, St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan
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47
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Chiţu V, Fajka-Boja R, Tóth GK, Váradi G, Hegedüs Z, Frankó A, Szücs KS, Monostori E. Comparative study on the effect of phosphorylated TCR zeta chain ITAM sequences on early activation events in Jurkat T cells. Peptides 2001; 22:1963-71. [PMID: 11786178 DOI: 10.1016/s0196-9781(01)00543-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
One of the main dilemma in T cell receptor (TCR) signal transduction is whether the presence of multiple Immunoreceptor Tyrosine-based Activation Motifs (ITAMs) within the TCR signaling module serves for signal amplification or signal distribution. To contribute to answer this question, we analyzed the effect of synthetic oligopeptides representing the three bi-phosphorylated zeta chain-ITAMs on the early signaling events in permeabilized leukemia T cells. Our main observations were as follows: 1/Stimulation of the cells with the bi-phosphorylated membrane proximal and central ITAMs (zeta (1)y(p)y(p) and zeta (2)y(p)y(p), respectively) resulted in a strong phosphorylation of proteins with a similar pattern. In contrast, the membrane distal ITAM, zeta (3)y(p)y(p) had a reduced ability to promote tyrosine phosphorylation and failed to induce the phosphorylation of a number of proteins. 2/ The phospho-peptide induced tyrosine phosphorylation events were at least partially mediated by p56(lck) and Syk/ZAP70 protein tyrosine kinases as it was shown in p56(lck) and Syk/ZAP70 deficient Jurkat variants. 3/The patterns of the association of the adaptor protein, Grb2 with tyrosine phosphorylated proteins following cell stimulation with the bi-phosphorylated membrane proximal or the central ITAMs were similar, while the membrane distal ITAM was unable to induce any of these associations. Our data provide additional evidence that the three zetaITAMs differ in their capacity to induce tyrosine phosphorylation of intracellular proteins in permeabilized T cells, depending to their primary sequence. The first and second ITAM sequences of the zeta chain may have similar but not totally overlapping functions. This conclusion results from their similar but not identical abilities to induce tyrosine phosphorylation and association of Grb-2 with intracellular phosphoproteins. In contrast, the third ITAM (zeta3) may have distinct functions since this peptide fails to induce tyrosine phosphorylation of a number of proteins compared to the other two ITAMs, and it is unable to induce either new association or the increase in the amount of Grb-2 associated phosphoproteins.
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Affiliation(s)
- V Chiţu
- Lymphocyte Signal Transduction Laboratory, Institute of Genetics, Biological Research Center, H-6726 Szeged, Temesvári krt. 62., Hungary
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48
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Wonerow P, Watson SP. The transmembrane adapter LAT plays a central role in immune receptor signalling. Oncogene 2001; 20:6273-83. [PMID: 11607829 DOI: 10.1038/sj.onc.1204770] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The transmembrane adapter LAT (linker for activation of T cells) plays a central role in signalling by ITAM bearing receptors expressed on T cells, natural killer cells, mast cells and platelets. Receptor engagement leads to the phosphorylation of tyrosine residues present in the intracellular domain of LAT and formation of a multiprotein complex with other adapter molecules and enzymes including Grb2, Gads/SLP-76 and PLCgamma isoforms. These signalling events predominantly take place in glycolipid-enriched membrane domains. The constitutive presence of LAT in GEMs enables its function as the main scaffolding protein for the organization of GEM-localized signalling. The study of LAT-deficient mice and LAT-deficient cell lines further emphasizes the importance of LAT for these signalling cascades but also defines the existence of LAT-independent events downstream of the Syk-family kinase-ITAM complex.
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Affiliation(s)
- P Wonerow
- Department of Pharmacology, University of Oxford, Mansfield Road, Oxford, OX1 3QT, UK.
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49
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Perez-Villar JJ, O'Day K, Hewgill DH, Nadler SG, Kanner SB. Nuclear localization of the tyrosine kinase Itk and interaction of its SH3 domain with karyopherin alpha (Rch1alpha). Int Immunol 2001; 13:1265-74. [PMID: 11581171 DOI: 10.1093/intimm/13.10.1265] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We report a physical and functional association between the Tec-family tyrosine kinase Itk (Emt/Tsk) and the nuclear import chaperone karyopherin alpha (Rch1alpha) in human T cells. The Itk-SH3 domain and the Rch1alpha proline-rich (PR) motif were crucial for the Itk/Rch1alpha constitutive interaction as demonstrated by directed mutagenesis of the Rch1alpha PR motif (proline 242 to alanine, P242A). TCR-CD3 stimulation of Jurkat T cells resulted in increased Itk/Rch1alpha complex formation, recruitment of karyopherin beta to the protein complex and Rch1alpha tyrosine phosphorylation. Analysis of in vitro kinase reactions with a panel of recombinant glutathione-S-transferase (GST) fusion tyrosine kinases (Itk, Lck, ZAP-70 and Jak3) revealed that only GST-Itk efficiently phosphorylated a recombinant GST-Rch1alpha fusion. We observed constitutive nuclear localization of Itk that was up-regulated following either TCR-CD3 stimulation or over-expression of wild-type Rch1alpha in T cells. Further, nuclear localization of Itk and TCR-CD3-mediated IL-2 production were significantly down-regulated following expression of the Rch1alpha-P242A mutant, implicating a role for Rch1alpha in the nuclear translocation of Itk.
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Affiliation(s)
- J J Perez-Villar
- Immunology, Inflammation, Pulmonology and Dermatology Discovery, Bristol-Myers Squibb Pharmaceutical Research Institute, Princeton, NJ 08543, USA
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50
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Verí MC, DeBell KE, Seminario MC, DiBaldassarre A, Reischl I, Rawat R, Graham L, Noviello C, Rellahan BL, Miscia S, Wange RL, Bonvini E. Membrane raft-dependent regulation of phospholipase Cgamma-1 activation in T lymphocytes. Mol Cell Biol 2001; 21:6939-50. [PMID: 11564877 PMCID: PMC99870 DOI: 10.1128/mcb.21.20.6939-6950.2001] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Numerous signaling molecules associate with lipid rafts, either constitutively or after engagement of surface receptors. One such molecule, phospholipase Cgamma-1 (PLCgamma1), translocates from the cytosol to lipid rafts during T-cell receptor (TCR) signaling. To investigate the role played by lipid rafts in the activation of this molecule in T cells, an influenza virus hemagglutinin A (HA)-tagged PLCgamma1 was ectopically expressed in Jurkat T cells and targeted to these microdomains by the addition of a dual-acylation signal. Raft-targeted PLCgamma1 was constitutively tyrosine phosphorylated and induced constitutive NF-AT-dependent transcription and interleukin-2 secretion in Jurkat cells. Tyrosine phosphorylation of raft-targeted PLCgamma1 did not require Zap-70 or the interaction with the adapters Lat and Slp-76, molecules that are necessary for TCR signaling. In contrast, the Src family kinase Lck was required. Coexpression in HEK 293T cells of PLCgamma1-HA with Lck or the Tec family kinase Rlk resulted in preferential phosphorylation of raft-targeted PLCgamma1 over wild-type PLCgamma1. These data show that localization of PLCgamma1 in lipid rafts is sufficient for its activation and demonstrate a role for lipid rafts as microdomains that dynamically segregate and integrate PLCgamma1 with other signaling components.
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Affiliation(s)
- M C Verí
- Laboratory of Immunobiology, Division of Monoclonal Antibodies, Center for Biologics Evaluation & Research, National Institute o f Health, Bethesda, Maryland 20892, USA
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