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Lee HN, Lee SE, Inn KS, Seong J. Optical sensing and control of T cell signaling pathways. Front Physiol 2024; 14:1321996. [PMID: 38269062 PMCID: PMC10806162 DOI: 10.3389/fphys.2023.1321996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2023] [Accepted: 12/20/2023] [Indexed: 01/26/2024] Open
Abstract
T cells regulate adaptive immune responses through complex signaling pathways mediated by T cell receptor (TCR). The functional domains of the TCR are combined with specific antibodies for the development of chimeric antigen receptor (CAR) T cell therapy. In this review, we first overview current understanding on the T cell signaling pathways as well as traditional methods that have been widely used for the T cell study. These methods, however, are still limited to investigating dynamic molecular events with spatiotemporal resolutions. Therefore, genetically encoded biosensors and optogenetic tools have been developed to study dynamic T cell signaling pathways in live cells. We review these cutting-edge technologies that revealed dynamic and complex molecular mechanisms at each stage of T cell signaling pathways. They have been primarily applied to the study of dynamic molecular events in TCR signaling, and they will further aid in understanding the mechanisms of CAR activation and function. Therefore, genetically encoded biosensors and optogenetic tools offer powerful tools for enhancing our understanding of signaling mechanisms in T cells and CAR-T cells.
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Affiliation(s)
- Hae Nim Lee
- Brain Science Institute, Korea Institute of Science and Technoloy, Seoul, Republic of Korea
- Department of Converging Science and Technology, Kyung Hee University, Seoul, Republic of Korea
| | - Seung Eun Lee
- Department of Pharmacology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Kyung-Soo Inn
- Department of Converging Science and Technology, Kyung Hee University, Seoul, Republic of Korea
| | - Jihye Seong
- Department of Pharmacology, Seoul National University College of Medicine, Seoul, Republic of Korea
- Wide River Institute of Immunology, Seoul National University, Hongcheon, Republic of Korea
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2
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Fernandes HB, de Oliveira IM, Postler TS, Lima SQ, Santos CAC, Oliveira MS, Leão FB, Ghosh S, Souza MC, Andrade W, Silva AM. Transcriptomic analysis reveals that RasGEF1b deletion alters basal and LPS-induced expression of genes involved in chemotaxis and cytokine responses in macrophages. Sci Rep 2023; 13:19614. [PMID: 37950057 PMCID: PMC10638313 DOI: 10.1038/s41598-023-47040-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 11/08/2023] [Indexed: 11/12/2023] Open
Abstract
Ras guanine nucleotide exchange factor member 1b (RasGEF1b) of the RasGEF/CDC25 domain-containing family is preferentially expressed by macrophages. However, information is lacking about its role in macrophage function. In this study, we generated mice with ubiquitous deletion of Rasgef1b and used RNA-seq-based transcriptomics to compare the global gene expression in wild-type and knock-out primary bone-marrow-derived macrophages under basal conditions and after lipopolysaccharide (LPS) treatment. Transcriptional filtering identified several genes with significantly different transcript levels between wild-type and knock-out macrophages. In total, 49 and 37 differentially expressed genes were identified at baseline and in LPS-activated macrophages, respectively. Distinct biological processes were significantly linked to down-regulated genes at the basal condition only, and largely included chemotaxis, response to cytokines, and positive regulation of GTPase activity. Importantly, validation by RT-qPCR revealed that the expression of genes identified as down-regulated after LPS stimulation was also decreased in the knock-out cells under basal conditions. We used a luciferase-based reporter assay to showcase the capability of RasGEF1b in activating the Serpinb2 promoter. Notably, knockdown of RasGEF1b in RAW264.7 macrophages resulted in impaired transcriptional activation of the Serpinb2 promoter, both in constitutive and LPS-stimulated conditions. This study provides a small collection of genes that shows relative expression changes effected by the absence of RasGEF1b in macrophages. Thus, we present the first evidence that RasGEF1b mediates the regulation of both steady-state and signal-dependent expression of genes and propose that this GEF plays a role in the maintenance of the basal transcriptional level in macrophages.
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Affiliation(s)
- Heliana B Fernandes
- Laboratory of Inflammatory Genes, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG, 31270-901, Brazil
| | - Isadora Mafra de Oliveira
- Laboratory of Inflammatory Genes, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG, 31270-901, Brazil
- Faculdade de Medicina de Ribeirão Preto, Av. Bandeirantes, 3900 - Campus da USP, Ribeirão Preto, SP, 14049-900, Brazil
| | - Thomas S Postler
- Department of Microbiology & Immunology, Vagelos College of Physicians & Surgeons, Columbia University Irving Medical Center, New York, NY, USA
- Design and Development Laboratory, International AIDS Vaccine Initiative, Brooklyn, NY, USA
| | - Sérgio Q Lima
- Laboratory of Inflammatory Genes, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG, 31270-901, Brazil
| | - Cícera A C Santos
- Laboratory of Inflammatory Genes, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG, 31270-901, Brazil
- Instituto Federal de Educação, Ciência e Tecnologia de Rondônia (IFRO), Guajará-Mirim, RO, Brazil
| | - Michaelle S Oliveira
- Laboratory of Inflammatory Genes, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG, 31270-901, Brazil
| | - Felipe B Leão
- Department of Microbiology & Immunology, Vagelos College of Physicians & Surgeons, Columbia University Irving Medical Center, New York, NY, USA
| | - Sankar Ghosh
- Department of Microbiology & Immunology, Vagelos College of Physicians & Surgeons, Columbia University Irving Medical Center, New York, NY, USA
| | - Maria C Souza
- Faculdade de Medicina de Ribeirão Preto, Av. Bandeirantes, 3900 - Campus da USP, Ribeirão Preto, SP, 14049-900, Brazil
| | - Warrison Andrade
- Faculdade de Medicina de Ribeirão Preto, Av. Bandeirantes, 3900 - Campus da USP, Ribeirão Preto, SP, 14049-900, Brazil
| | - Aristóbolo M Silva
- Laboratory of Inflammatory Genes, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG, 31270-901, Brazil.
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3
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Johansen KH, Golec DP, Okkenhaug K, Schwartzberg PL. Mind the GAP: RASA2 and RASA3 GTPase-activating proteins as gatekeepers of T cell activation and adhesion. Trends Immunol 2023; 44:917-931. [PMID: 37858490 PMCID: PMC10621891 DOI: 10.1016/j.it.2023.09.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Revised: 09/11/2023] [Accepted: 09/11/2023] [Indexed: 10/21/2023]
Abstract
Following stimulation, the T cell receptor (TCR) and its coreceptors integrate multiple intracellular signals to initiate T cell proliferation, migration, gene expression, and metabolism. Among these signaling molecules are the small GTPases RAS and RAP1, which induce MAPK pathways and cellular adhesion to activate downstream effector functions. Although many studies have helped to elucidate the signaling intermediates that mediate T cell activation, the molecules and pathways that keep naive T cells in check are less understood. Several recent studies provide evidence that RASA2 and RASA3, which are GAP1-family GTPase-activating proteins (GAPs) that inactivate RAS and RAP1, respectively, are crucial molecules that limit T cell activation and adhesion. In this review we describe recent data on the roles of RASA2 and RASA3 as gatekeepers of T cell activation and migration.
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Affiliation(s)
- Kristoffer H Johansen
- Cell Signaling and Immunity Section, Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA; Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK; Section of Experimental and Translational Immunology, Department of Health Technology, Technical University of Denmark, 2800 Kongens Lyngby, Denmark.
| | - Dominic P Golec
- Cell Signaling and Immunity Section, Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Klaus Okkenhaug
- Department of Pathology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QP, UK
| | - Pamela L Schwartzberg
- Cell Signaling and Immunity Section, Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
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4
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Chang Y, Manivannan P, Doosti A, Lapinski PE, Chen D, Roose J, King PD. Cutting Edge: Induced Loss of Rasgrp1 in Peripheral CD4+ T Cells of Conditional Rasgrp1-Deficient Mice Reveals an Essential Role for Rasgrp1 in TCR/CD28-Induced Ras-MAPK Signaling. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2023; 211:917-922. [PMID: 37566514 PMCID: PMC10529702 DOI: 10.4049/jimmunol.2300138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Accepted: 07/25/2023] [Indexed: 08/13/2023]
Abstract
Ras guanine nucleotide-releasing protein 1 (Rasgrp1) is a Ras guanine nucleotide exchange factor that participates in the activation of the Ras-ERK signaling pathway in developing T cells and is required for efficient thymic T cell positive selection. However, the role of Rasgrp1 in mature peripheral T cells has not been definitively addressed, in part because peripheral T cells from constitutive Rasgrp1-deficient mice show an abnormal activated phenotype. In this study, we generated an inducible Rasgrp1-deficient mouse model to allow acute disruption of Rasgrp1 in peripheral CD4+ T cells in the context of normal T cell development. TCR/CD28-mediated activation of Ras-ERK signaling was blocked in Rasgrp1-deficient peripheral CD4+ T cells. Furthermore, Rasgrp1-deficient CD4+ T cells were unable to synthesize IL-2 and the high-affinity IL-2R and were unable to proliferate in response to TCR/CD28 stimulation. These findings highlight an essential function for Rasgrp1 for TCR/CD28-induced Ras-ERK activation in peripheral CD4+ T cells.
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Affiliation(s)
- Yating Chang
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Praveen Manivannan
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Abbas Doosti
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Philip E. Lapinski
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Di Chen
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Jeroen Roose
- Department of Anatomy, University of California, San Francisco, USA
| | - Philip D. King
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
- Department of Anatomy, University of California, San Francisco, USA
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Jin H, Koh M, Lim H, Yong HY, Kim ES, Kim SY, Kim K, Jung J, Ryu WJ, Choi KY, Moon A. Lipid raft protein flotillin-1 is important for the interaction between SOS1 and H-Ras/K-Ras, leading to Ras activation. Int J Cancer 2023; 152:1933-1946. [PMID: 36691829 DOI: 10.1002/ijc.34443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 12/20/2022] [Accepted: 01/16/2023] [Indexed: 01/25/2023]
Abstract
Ras mutations have been frequently observed in human cancer. Although there is a high degree of similarity between Ras isomers, they display preferential coupling in specific cancer types. The binding of Ras to the plasma membrane is essential for its activation and biological functions. The present study elucidated Ras isoform-specific interactions with the membrane and their role in Ras-mediated biological activities. We investigated the role of a lipid raft protein flotillin-1 (Flot-1) in the activations of Ras. We found that Flot-1 was co-localized with H-Ras, but not with N-Ras, in lipid rafts of MDA-MB-231 human breast cells. The amino-terminal hydrophobic domain (1-38) of Flot-1 interacted with the hypervariable region of H-Ras. The epidermal growth factor-stimulated activation of H-Ras required Flot-1 which was not necessary for that of N-Ras in breast cancer cells. Flot-1 interacted with son of sevenless (SOS)-1, which promotes the conversion of Ras-bound GDP to GTP. Notably, Flot-1 was crucial for the interaction between SOS1 and H-Ras/K-Ras in breast and pancreatic cancer cells. Stable knockdown of Flot-1 reduced the in vivo metastasis in a mouse xenograft model with human breast carcinoma cells. A tissue microarray composed of 61 human pancreatic cancer samples showed higher levels of Flot-1 expression in pancreatic tumor tissues compared to normal tissues, and a correlation between K-Ras and Flot-1. Taken together, our findings suggest that Flot-1 may serve as a membrane platform for the interaction of SOS1 with H-Ras/K-Ras in human cancer cells, presenting Flot-1 as a potential target for Ras-driven cancers.
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Affiliation(s)
- Hao Jin
- Duksung Innovative Drug Center, College of Pharmacy, Duksung Women's University, Seoul, South Korea
| | - Minsoo Koh
- Duksung Innovative Drug Center, College of Pharmacy, Duksung Women's University, Seoul, South Korea
| | - Hyesol Lim
- Duksung Innovative Drug Center, College of Pharmacy, Duksung Women's University, Seoul, South Korea
| | - Hae-Young Yong
- Duksung Innovative Drug Center, College of Pharmacy, Duksung Women's University, Seoul, South Korea
| | - Eun-Sook Kim
- Duksung Innovative Drug Center, College of Pharmacy, Duksung Women's University, Seoul, South Korea
| | - Sun Young Kim
- Department of Chemistry, College of Science and Technology, Duksung Women's University, Seoul, Republic of Korea
| | - Kyoungmee Kim
- Duksung Innovative Drug Center, College of Pharmacy, Duksung Women's University, Seoul, South Korea
| | - Joohee Jung
- Duksung Innovative Drug Center, College of Pharmacy, Duksung Women's University, Seoul, South Korea
| | - Won-Ji Ryu
- Avison Biomedical Research Center, Yonsei University College of Medicine, Seoul, South Korea
| | - Kang-Yell Choi
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, South Korea
| | - Aree Moon
- Duksung Innovative Drug Center, College of Pharmacy, Duksung Women's University, Seoul, South Korea
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A Focused Review of Ras Guanine Nucleotide-Releasing Protein 1 in Immune Cells and Cancer. Int J Mol Sci 2023; 24:ijms24021652. [PMID: 36675167 PMCID: PMC9864139 DOI: 10.3390/ijms24021652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 01/11/2023] [Accepted: 01/12/2023] [Indexed: 01/18/2023] Open
Abstract
Four Ras guanine nucleotide-releasing proteins (RasGRP1 through 4) belong to the family of guanine nucleotide exchange factors (GEFs). RasGRPs catalyze the release of GDP from small GTPases Ras and Rap and facilitate their transition from an inactive GDP-bound to an active GTP-bound state. Thus, they regulate critical cellular responses via many downstream GTPase effectors. Similar to other RasGRPs, the catalytic module of RasGRP1 is composed of the Ras exchange motif (REM) and Cdc25 domain, and the EF hands and C1 domain contribute to its cellular localization and regulation. RasGRP1 can be activated by a diacylglycerol (DAG)-mediated membrane recruitment and protein kinase C (PKC)-mediated phosphorylation. RasGRP1 acts downstream of the T cell receptor (TCR), B cell receptors (BCR), and pre-TCR, and plays an important role in the thymocyte maturation and function of peripheral T cells, B cells, NK cells, mast cells, and neutrophils. The dysregulation of RasGRP1 is known to contribute to numerous disorders that range from autoimmune and inflammatory diseases and schizophrenia to neoplasia. Given its position at the crossroad of cell development, inflammation, and cancer, RASGRP1 has garnered interest from numerous disciplines. In this review, we outline the structure, function, and regulation of RasGRP1 and focus on the existing knowledge of the role of RasGRP1 in leukemia and other cancers.
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Henriques SN, Oliveira L, Santos RF, Carmo AM. CD6-mediated inhibition of T cell activation via modulation of Ras. Cell Commun Signal 2022; 20:184. [PMID: 36414966 PMCID: PMC9682754 DOI: 10.1186/s12964-022-00998-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Accepted: 10/16/2022] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND CD6 is one of many cell surface receptors known to regulate signal transduction upon T cell activation. However, whether CD6 mediates costimulatory or inhibitory signals is controversial. When T cells engage with antigen presenting cells (APCs), CD6 interacts with its ligand CD166 at the cell-cell interface while the cytosolic tail assembles a complex signalosome composed of adaptors and effector enzymes, that may either trigger activating signaling cascades, or instead modulate the intensity of signaling. Except for a few cytosolic adaptors that connect different components of the CD6 signalosome, very little is known about the mechanistic effects of the cytosolic effectors that bind CD6. METHODS Jurkat model T cells were transfected to express wild-type (WT) CD6, or a cytoplasmic truncation, signaling-disabled mutant, CD6Δcyt. The two resulting cell lines were directly activated by superantigen (sAg)-loaded Raji cells, used as APCs, to assess the net signaling function of CD6. The Jurkat cell lines were further adapted to express a FRET-based unimolecular HRas biosensor that reported the activity of this crucial GTPase at the immunological synapse. RESULTS We show that deletion of the cytosolic tail of CD6 enhances T-cell responses, indicating that CD6 restrains T-cell activation. One component of the CD6-associated inhibitory apparatus was found to be the GTPase activating protein of Ras (RasGAP), that we show to associate with CD6 in a phosphorylation-dependent manner. The FRET HRas biosensor that we developed was demonstrated to be functional and reporting the activation of the T cell lines. This allowed to determine that the presence of the cytosolic tail of CD6 results in the down-regulation of HRas activity at the immunological synapse, implicating this fundamental GTPase as one of the targets inhibited by CD6. CONCLUSIONS This study provides the first description of a mechanistic sequence of events underlying the CD6-mediated inhibition of T-cell activation, involving the modulation of the MAPK pathway at several steps, starting with the coupling of RasGAP to the CD6 signalosome, the repression of the activity of Ras, and culminating in the reduction of ERK1/2 phosphorylation and of the expression of the T-cell activation markers CD69 and IL-2R α chain. Video abstract.
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Affiliation(s)
- Sónia N. Henriques
- grid.5808.50000 0001 1503 7226i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal ,grid.5808.50000 0001 1503 7226IBMC - Instituto de Biologia Molecular e Celular, Porto, Portugal ,grid.5808.50000 0001 1503 7226Programa Doutoral em Biologia Molecular e Celular (MCbiology), Instituto de Ciências Biomédicas Abel Salazar (ICBAS), Universidade do Porto, Porto, Portugal
| | - Liliana Oliveira
- grid.5808.50000 0001 1503 7226i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal ,grid.5808.50000 0001 1503 7226IBMC - Instituto de Biologia Molecular e Celular, Porto, Portugal
| | - Rita F. Santos
- grid.5808.50000 0001 1503 7226i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal ,grid.5808.50000 0001 1503 7226IBMC - Instituto de Biologia Molecular e Celular, Porto, Portugal
| | - Alexandre M. Carmo
- grid.5808.50000 0001 1503 7226i3S - Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen, 208, 4200-135 Porto, Portugal ,grid.5808.50000 0001 1503 7226IBMC - Instituto de Biologia Molecular e Celular, Porto, Portugal
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Pisanti S, Rimondi E, Pozza E, Melloni E, Zauli E, Bifulco M, Martinelli R, Marcuzzi A. Prenylation Defects and Oxidative Stress Trigger the Main Consequences of Neuroinflammation Linked to Mevalonate Pathway Deregulation. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19159061. [PMID: 35897423 PMCID: PMC9332440 DOI: 10.3390/ijerph19159061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 07/20/2022] [Accepted: 07/21/2022] [Indexed: 12/10/2022]
Abstract
The cholesterol biosynthesis represents a crucial metabolic pathway for cellular homeostasis. The end products of this pathway are sterols, such as cholesterol, which are essential components of cell membranes, precursors of steroid hormones, bile acids, and other molecules such as ubiquinone. Furthermore, some intermediates of this metabolic system perform biological activity in specific cellular compartments, such as isoprenoid molecules that can modulate different signal proteins through the prenylation process. The defects of prenylation represent one of the main causes that promote the activation of inflammation. In particular, this mechanism, in association with oxidative stress, induces a dysfunction of the mitochondrial activity. The purpose of this review is to describe the pleiotropic role of prenylation in neuroinflammation and to highlight the consequence of the defects of prenylation.
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Affiliation(s)
- Simona Pisanti
- Department of Medicine, Surgery and Dentistry ′Scuola Medica Salernitana′, University of Salerno, 84081 Baronissi, Italy; (S.P.); (R.M.)
| | - Erika Rimondi
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy; (E.P.); (E.Z.); (A.M.)
- LTTA Centre, University of Ferrara, 44121 Ferrara, Italy
- Correspondence: (E.R.); (E.M.)
| | - Elena Pozza
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy; (E.P.); (E.Z.); (A.M.)
| | - Elisabetta Melloni
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy; (E.P.); (E.Z.); (A.M.)
- LTTA Centre, University of Ferrara, 44121 Ferrara, Italy
- Correspondence: (E.R.); (E.M.)
| | - Enrico Zauli
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy; (E.P.); (E.Z.); (A.M.)
| | - Maurizio Bifulco
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples “Federico II”, 80131 Naples, Italy;
| | - Rosanna Martinelli
- Department of Medicine, Surgery and Dentistry ′Scuola Medica Salernitana′, University of Salerno, 84081 Baronissi, Italy; (S.P.); (R.M.)
| | - Annalisa Marcuzzi
- Department of Translational Medicine, University of Ferrara, 44121 Ferrara, Italy; (E.P.); (E.Z.); (A.M.)
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Abstract
RAS proteins play major roles in many human cancers, but programs to develop direct RAS inhibitors so far have only been successful for the oncogenic KRAS mutant G12C. As an alternative approach, inhibitors for the RAS guanine nucleotide exchange factor SOS1 have been investigated by several academic groups and companies, and major progress has been achieved in recent years in the optimization of small molecule activators and inhibitors of SOS1. Here, we review the discovery and development of small molecule modulators of SOS1 and their molecular binding modes and modes of action. As targeting the RAS pathway is expected to result in the development of resistance mechanisms, SOS1 inhibitors will most likely be best applied in vertical combination approaches where two nodes of the RAS signaling pathway are hit simultaneously. We summarize the current understanding of which combination partners may be most beneficial for patients with RAS driven tumors.
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Affiliation(s)
| | - Benjamin Bader
- Screening, Lead Discovery, Nuvisan ICB GmbH, Berlin, Germany
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10
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Nicolas P, Ollier J, Mori D, Voisinne G, Celis-Gutierrez J, Gregoire C, Perroteau J, Vivien R, Camus M, Burlet-Schiltz O, Gonzalez de Peredo A, Clémenceau B, Roncagalli R, Vié H, Malissen B. Systems-level conservation of the proximal TCR signaling network of mice and humans. J Exp Med 2022; 219:212976. [PMID: 35061003 PMCID: PMC8789201 DOI: 10.1084/jem.20211295] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 10/11/2021] [Accepted: 11/23/2021] [Indexed: 12/23/2022] Open
Abstract
We exploited traceable gene tagging in primary human T cells to establish the composition and dynamics of seven canonical TCR-induced protein signaling complexes (signalosomes) using affinity purification coupled with mass spectrometry (AP-MS). It unveiled how the LAT adaptor assembles higher-order molecular condensates and revealed that the proximal TCR-signaling network has a high degree of qualitative and quantitative conservation between human CD4+ and CD8+ T cells. Such systems-level conservation also extended across human and mouse T cells and unexpectedly encompassed protein–protein interaction stoichiometry. Independently of evolutionary considerations, our study suggests that a drug targeting the proximal TCR signaling network should behave similarly when applied to human and mouse T cells. However, considering that signaling differences likely exist between the distal TCR-signaling pathway of human and mouse, our fast-track AP-MS approach should be favored to determine the mechanism of action of drugs targeting human T cell activation. An opportunity is illustrated here using an inhibitor of the LCK protein tyrosine kinase as a proof-of-concept.
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Affiliation(s)
- Philippe Nicolas
- Centre d’Immunologie de Marseille-Luminy, Aix Marseille Université, Institut national de la santé et de la recherche médicale, Centre national de la recherche scientifique, Marseille, France
| | - Jocelyn Ollier
- Centre de Recherche en Cancérologie et Immunologie Nantes Angers, Institut national de la santé et de la recherche médicale, Centre national de la recherche scientifique, Université d'Angers, Université de Nantes, Nantes, France
- LabEx Immunotherapy–Graft–Oncology, Nantes, France
| | - Daiki Mori
- Centre d’Immunologie de Marseille-Luminy, Aix Marseille Université, Institut national de la santé et de la recherche médicale, Centre national de la recherche scientifique, Marseille, France
- Centre d’Immunophénomique, Aix Marseille Université, Institut national de la santé et de la recherche médicale, Centre national de la recherche scientifique, Marseille, France
| | - Guillaume Voisinne
- Centre d’Immunologie de Marseille-Luminy, Aix Marseille Université, Institut national de la santé et de la recherche médicale, Centre national de la recherche scientifique, Marseille, France
| | - Javier Celis-Gutierrez
- Centre d’Immunologie de Marseille-Luminy, Aix Marseille Université, Institut national de la santé et de la recherche médicale, Centre national de la recherche scientifique, Marseille, France
- Centre d’Immunophénomique, Aix Marseille Université, Institut national de la santé et de la recherche médicale, Centre national de la recherche scientifique, Marseille, France
| | - Claude Gregoire
- Centre d’Immunologie de Marseille-Luminy, Aix Marseille Université, Institut national de la santé et de la recherche médicale, Centre national de la recherche scientifique, Marseille, France
| | - Jeanne Perroteau
- Centre d’Immunologie de Marseille-Luminy, Aix Marseille Université, Institut national de la santé et de la recherche médicale, Centre national de la recherche scientifique, Marseille, France
| | - Régine Vivien
- Centre de Recherche en Cancérologie et Immunologie Nantes Angers, Institut national de la santé et de la recherche médicale, Centre national de la recherche scientifique, Université d'Angers, Université de Nantes, Nantes, France
- LabEx Immunotherapy–Graft–Oncology, Nantes, France
| | - Mylène Camus
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, Centre national de la recherche scientifique Université Paul Sabatier, Toulouse, France
| | - Odile Burlet-Schiltz
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, Centre national de la recherche scientifique Université Paul Sabatier, Toulouse, France
| | - Anne Gonzalez de Peredo
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, Centre national de la recherche scientifique Université Paul Sabatier, Toulouse, France
| | - Béatrice Clémenceau
- Centre de Recherche en Cancérologie et Immunologie Nantes Angers, Institut national de la santé et de la recherche médicale, Centre national de la recherche scientifique, Université d'Angers, Université de Nantes, Nantes, France
- LabEx Immunotherapy–Graft–Oncology, Nantes, France
| | - Romain Roncagalli
- Centre d’Immunologie de Marseille-Luminy, Aix Marseille Université, Institut national de la santé et de la recherche médicale, Centre national de la recherche scientifique, Marseille, France
| | - Henri Vié
- Centre de Recherche en Cancérologie et Immunologie Nantes Angers, Institut national de la santé et de la recherche médicale, Centre national de la recherche scientifique, Université d'Angers, Université de Nantes, Nantes, France
- LabEx Immunotherapy–Graft–Oncology, Nantes, France
| | - Bernard Malissen
- Centre d’Immunologie de Marseille-Luminy, Aix Marseille Université, Institut national de la santé et de la recherche médicale, Centre national de la recherche scientifique, Marseille, France
- Centre d’Immunophénomique, Aix Marseille Université, Institut national de la santé et de la recherche médicale, Centre national de la recherche scientifique, Marseille, France
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11
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Cuesta C, Arévalo-Alameda C, Castellano E. The Importance of Being PI3K in the RAS Signaling Network. Genes (Basel) 2021; 12:genes12071094. [PMID: 34356110 PMCID: PMC8303222 DOI: 10.3390/genes12071094] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 07/06/2021] [Accepted: 07/16/2021] [Indexed: 12/12/2022] Open
Abstract
Ras proteins are essential mediators of a multitude of cellular processes, and its deregulation is frequently associated with cancer appearance, progression, and metastasis. Ras-driven cancers are usually aggressive and difficult to treat. Although the recent Food and Drug Administration (FDA) approval of the first Ras G12C inhibitor is an important milestone, only a small percentage of patients will benefit from it. A better understanding of the context in which Ras operates in different tumor types and the outcomes mediated by each effector pathway may help to identify additional strategies and targets to treat Ras-driven tumors. Evidence emerging in recent years suggests that both oncogenic Ras signaling in tumor cells and non-oncogenic Ras signaling in stromal cells play an essential role in cancer. PI3K is one of the main Ras effectors, regulating important cellular processes such as cell viability or resistance to therapy or angiogenesis upon oncogenic Ras activation. In this review, we will summarize recent advances in the understanding of Ras-dependent activation of PI3K both in physiological conditions and cancer, with a focus on how this signaling pathway contributes to the formation of a tumor stroma that promotes tumor cell proliferation, migration, and spread.
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12
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Dadwal N, Mix C, Reinhold A, Witte A, Freund C, Schraven B, Kliche S. The Multiple Roles of the Cytosolic Adapter Proteins ADAP, SKAP1 and SKAP2 for TCR/CD3 -Mediated Signaling Events. Front Immunol 2021; 12:703534. [PMID: 34295339 PMCID: PMC8290198 DOI: 10.3389/fimmu.2021.703534] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 06/21/2021] [Indexed: 12/24/2022] Open
Abstract
T cells are the key players of the adaptive immune response. They coordinate the activation of other immune cells and kill malignant and virus-infected cells. For full activation T cells require at least two signals. Signal 1 is induced after recognition of MHC/peptide complexes presented on antigen presenting cells (APCs) by the clonotypic TCR (T-cell receptor)/CD3 complex whereas Signal 2 is mediated via the co-stimulatory receptor CD28, which binds to CD80/CD86 molecules that are present on APCs. These signaling events control the activation, proliferation and differentiation of T cells. In addition, triggering of the TCR/CD3 complex induces the activation of the integrin LFA-1 (leukocyte function associated antigen 1) leading to increased ligand binding (affinity regulation) and LFA-1 clustering (avidity regulation). This process is termed "inside-out signaling". Subsequently, ligand bound LFA-1 transmits a signal into the T cells ("outside-in signaling") which enhances T-cell interaction with APCs (adhesion), T-cell activation and T-cell proliferation. After triggering of signal transducing receptors, adapter proteins organize the proper processing of membrane proximal and intracellular signals as well as the activation of downstream effector molecules. Adapter proteins are molecules that lack enzymatic or transcriptional activity and are composed of protein-protein and protein-lipid interacting domains/motifs. They organize and assemble macromolecular complexes (signalosomes) in space and time. Here, we review recent findings regarding three cytosolic adapter proteins, ADAP (Adhesion and Degranulation-promoting Adapter Protein), SKAP1 and SKAP2 (Src Kinase Associated Protein 1 and 2) with respect to their role in TCR/CD3-mediated activation, proliferation and integrin regulation.
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Affiliation(s)
- Nirdosh Dadwal
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
| | - Charlie Mix
- Institute of Molecular and Clinical Immunology, Health Campus Immunology, Infectiology and Inflammation (GCI3), Medical Faculty of the Otto-von-Guericke University, Magdeburg, Germany
| | - Annegret Reinhold
- Institute of Molecular and Clinical Immunology, Health Campus Immunology, Infectiology and Inflammation (GCI3), Medical Faculty of the Otto-von-Guericke University, Magdeburg, Germany
| | - Amelie Witte
- Coordination Center of Clinical Trials, University Medicine Greifswald, Greifswald, Germany
| | - Christian Freund
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
| | - Burkhart Schraven
- Institute of Molecular and Clinical Immunology, Health Campus Immunology, Infectiology and Inflammation (GCI3), Medical Faculty of the Otto-von-Guericke University, Magdeburg, Germany
| | - Stefanie Kliche
- Institute of Molecular and Clinical Immunology, Health Campus Immunology, Infectiology and Inflammation (GCI3), Medical Faculty of the Otto-von-Guericke University, Magdeburg, Germany
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13
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Regulation of the Small GTPase Ras and Its Relevance to Human Disease. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2021; 2262:19-43. [PMID: 33977469 DOI: 10.1007/978-1-0716-1190-6_2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Ras research has experienced a considerable boost in recent years, not least prompted by the Ras initiative launched by the NCI in 2013 ( https://www.cancer.gov/research/key-initiatives/ras ), accompanied and conditioned by a strongly reinvigorated determination within the Ras community to develop therapeutics attacking directly the Ras oncoproteins. As a member of the small G-protein superfamily, function and transforming activity of Ras all revolve about its GDP/GTP loading status. For one thing, the extent of GTP loading will determine the proportion of active Ras in the cell, with implications for intensity and quality of downstream signaling. But also the rate of nucleotide exchange, i.e., the Ras-GDP/GTP cycling rate, can have a major impact on Ras function, as illustrated perhaps most impressively by newly discovered fast-cycling oncogenic mutants of the Ras-related GTPase Rac1. Thus, while the last years have witnessed memorable new findings and technical developments in the Ras field, leading to an improved insight into many aspects of Ras biology, they have not jolted at the basics, but rather deepened our view of the fundamental regulatory principles of Ras activity control. In this brief review, we revisit the role and mechanisms of Ras nucleotide loading and its implications for cancer in the light of recent findings.
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14
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Membrane therapy using DHA suppresses epidermal growth factor receptor signaling by disrupting nanocluster formation. J Lipid Res 2021; 62:100026. [PMID: 33515553 PMCID: PMC7933808 DOI: 10.1016/j.jlr.2021.100026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Revised: 01/11/2021] [Accepted: 01/19/2021] [Indexed: 02/07/2023] Open
Abstract
Epidermal growth factor receptor (EGFR) signaling drives the formation of many types of cancer, including colon cancer. Docosahexaenoic acid (DHA, 22∶6Δ4,7,10,13,16,19), a chemoprotective long-chain n-3 polyunsaturated fatty acid suppresses EGFR signaling. However, the mechanism underlying this phenotype remains unclear. Therefore, we used super-resolution microscopy techniques to investigate the mechanistic link between EGFR function and DHA-induced alterations to plasma membrane nanodomains. Using isogenic in vitro (YAMC and IMCE mouse colonic cell lines) and in vivo (Drosophila, wild type and Fat-1 mice) models, cellular DHA enrichment via therapeutic nanoparticle delivery, endogenous synthesis, or dietary supplementation reduced EGFR-mediated cell proliferation and downstream Ras/ERK signaling. Phospholipid incorporation of DHA reduced membrane rigidity and the size of EGFR nanoclusters. Similarly, pharmacological reduction of plasma membrane phosphatidic acid (PA), phosphatidylinositol-4,5-bisphosphate (PIP2) or cholesterol was associated with a decrease in EGFR nanocluster size. Furthermore, in DHA-treated cells only the addition of cholesterol, unlike PA or PIP2, restored EGFR nanoscale clustering. These findings reveal that DHA reduces EGFR signaling in part by reshaping EGFR proteolipid nanodomains, supporting the feasibility of using membrane therapy, i.e., dietary/drug-related strategies to target plasma membrane organization, to reduce EGFR signaling and cancer risk.
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15
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Baltanás FC, Zarich N, Rojas-Cabañeros JM, Santos E. SOS GEFs in health and disease. Biochim Biophys Acta Rev Cancer 2020; 1874:188445. [PMID: 33035641 DOI: 10.1016/j.bbcan.2020.188445] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 10/01/2020] [Accepted: 10/01/2020] [Indexed: 12/11/2022]
Abstract
SOS1 and SOS2 are the most universal and widely expressed family of guanine exchange factors (GEFs) capable or activating RAS or RAC1 proteins in metazoan cells. SOS proteins contain a sequence of modular domains that are responsible for different intramolecular and intermolecular interactions modulating mechanisms of self-inhibition, allosteric activation and intracellular homeostasis. Despite their homology, analyses of SOS1/2-KO mice demonstrate functional prevalence of SOS1 over SOS2 in cellular processes including proliferation, migration, inflammation or maintenance of intracellular redox homeostasis, although some functional redundancy cannot be excluded, particularly at the organismal level. Specific SOS1 gain-of-function mutations have been identified in inherited RASopathies and various sporadic human cancers. SOS1 depletion reduces tumorigenesis mediated by RAS or RAC1 in mouse models and is associated with increased intracellular oxidative stress and mitochondrial dysfunction. Since WT RAS is essential for development of RAS-mutant tumors, the SOS GEFs may be considered as relevant biomarkers or therapy targets in RAS-dependent cancers. Inhibitors blocking SOS expression, intrinsic GEF activity, or productive SOS protein-protein interactions with cellular regulators and/or RAS/RAC targets have been recently developed and shown preclinical and clinical effectiveness blocking aberrant RAS signaling in RAS-driven and RTK-driven tumors.
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Affiliation(s)
- Fernando C Baltanás
- Centro de Investigación del Cáncer - IBMCC (CSIC-USAL) and CIBERONC, Universidad de Salamanca, 37007 Salamanca, Spain
| | - Natasha Zarich
- Unidad Funcional de Investigación de Enfermedades Crónicas (UFIEC) and CIBERONC, Instituto de Salud Carlos III, 28220, Majadahonda, Madrid, Spain
| | - Jose M Rojas-Cabañeros
- Unidad Funcional de Investigación de Enfermedades Crónicas (UFIEC) and CIBERONC, Instituto de Salud Carlos III, 28220, Majadahonda, Madrid, Spain
| | - Eugenio Santos
- Centro de Investigación del Cáncer - IBMCC (CSIC-USAL) and CIBERONC, Universidad de Salamanca, 37007 Salamanca, Spain.
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16
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Increased baseline RASGRP1 signals enhance stem cell fitness during native hematopoiesis. Oncogene 2020; 39:6920-6934. [PMID: 32989257 PMCID: PMC7655557 DOI: 10.1038/s41388-020-01469-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 09/10/2020] [Indexed: 02/06/2023]
Abstract
Oncogenic mutations in RAS genes, like KRASG12D or NRASG12D, trap Ras in the active state and cause myeloproliferative disorder and T cell leukemia (T-ALL) when induced in the bone marrow via Mx1CRE. The RAS exchange factor RASGRP1 is frequently overexpressed in T-ALL patients. In T-ALL cell lines overexpression of RASGRP1 increases flux through the RASGTP/RasGDP cycle. Here we expanded RASGRP1 expression surveys in pediatric T-ALL and generated a RoLoRiG mouse model crossed to Mx1CRE to determine the consequences of induced RASGRP1 overexpression in primary hematopoietic cells. RASGRP1-overexpressing, GFP-positive cells outcompeted wild type cells and dominated the peripheral blood compartment over time. RASGRP1 overexpression bestows gain-of-function colony formation properties to bone marrow progenitors in medium containing limited growth factors. RASGRP1 overexpression enhances baseline mTOR-S6 signaling in the bone marrow, but not in vitro cytokine-induced signals. In agreement with these mechanistic findings, hRASGRP1-ires-EGFP enhances fitness of stem- and progenitor- cells, but only in the context of native hematopoiesis. RASGRP1 overexpression is distinct from KRASG12D or NRASG12D, does not cause acute leukemia on its own, and leukemia virus insertion frequencies predict that RASGRP1 overexpression can effectively cooperate with lesions in many other genes to cause acute T cell leukemia.
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17
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Leão FB, Vaughn LS, Bhatt D, Liao W, Maloney D, Carvalho BC, Oliveira L, Ghosh S, Silva AM. Toll-like Receptor (TLR)-induced Rasgef1b expression in macrophages is regulated by NF-κB through its proximal promoter. Int J Biochem Cell Biol 2020; 127:105840. [PMID: 32866686 DOI: 10.1016/j.biocel.2020.105840] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 07/31/2020] [Accepted: 08/21/2020] [Indexed: 12/21/2022]
Abstract
Ras Guanine Exchange Factor (RasGEF) domain family member 1b is encoded by a Toll-like receptor (TLR)-inducible gene expressed in macrophages, but transcriptional mechanisms that govern its expression are still unknown. Here, we have functionally characterized the 5' flanking Rasgef1b sequence and analyzed its transcriptional activation. We have identified that the inflammation-responsive promoter is contained within a short sequence (-183 to +119) surrounding the transcriptional start site. The promoter sequence is evolutionarily conserved and harbors a cluster of five NF-κB binding sites. Luciferase reporter gene assay showed that the promoter is responsive to TLR activation and RelA or cRel, but not RelB, transcription factors. Besides, site-directed mutagenesis showed that the κB binding sites are required for maximal promoter activation induced by LPS. Analysis by Assay for Transposase-Accessible Chromatin using sequencing (ATAC-seq) revealed that the promoter is located in an accessible chromatin region. More important, Chromatin Immunoprecipitation sequencing (ChIP-seq) showed that RelA is recruited to the promoter region upon LPS stimulation of bone marrow-derived macrophages. Finally, studies with Rela-deficient macrophages or pharmacological inhibition by Bay11-7082 showed that NF-κB is required for optimal Rasgef1b expression induced by TLR agonists. Our data provide evidence of the regulatory mechanism mediated by NF-κB that facilitates Rasgef1b expression after TLR activation in macrophages.
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Affiliation(s)
- Felipe B Leão
- Laboratory of Inflammatory Genes, Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais (UFMG), Belo Horizonte, MG, Brazil
| | - Lauren S Vaughn
- Department of Microbiology & Immunology, Columbia University, College of Physicians and Surgeons, New York, NY 10031, USA
| | - Dev Bhatt
- Department of Microbiology & Immunology, Columbia University, College of Physicians and Surgeons, New York, NY 10031, USA
| | - Will Liao
- New York Genome Center, New York, NY 10013, USA
| | | | - Brener C Carvalho
- Laboratory of Inflammatory Genes, Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais (UFMG), Belo Horizonte, MG, Brazil
| | - Leonardo Oliveira
- Laboratory of Inflammatory Genes, Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais (UFMG), Belo Horizonte, MG, Brazil
| | - Sankar Ghosh
- Department of Microbiology & Immunology, Columbia University, College of Physicians and Surgeons, New York, NY 10031, USA
| | - Aristóbolo M Silva
- Laboratory of Inflammatory Genes, Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais (UFMG), Belo Horizonte, MG, Brazil.
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18
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Umutesi HG, Hoang HM, Johnson HE, Nam K, Heo J. Development of Noonan syndrome by deregulation of allosteric SOS autoactivation. J Biol Chem 2020; 295:13651-13663. [PMID: 32753483 DOI: 10.1074/jbc.ra120.013275] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 07/30/2020] [Indexed: 11/06/2022] Open
Abstract
Ras family proteins play an essential role in several cellular functions, including growth, differentiation, and survival. The mechanism of action of Ras mutants in Costello syndrome and cancers has been identified, but the contribution of Ras mutants to Noonan syndrome, a genetic disorder that prevents normal development in various parts of the body, is unknown. Son of Sevenless (SOS) is a Ras guanine nucleotide exchange factor. In response to Ras-activating cell signaling, SOS autoinhibition is released and is followed by accelerative allosteric feedback autoactivation. Here, using mutagenesis-based kinetic and pulldown analyses, we show that Noonan syndrome Ras mutants I24N, T50I, V152G, and D153V deregulate the autoactivation of SOS to populate their active form. This previously unknown process has been linked so far only to the development of Noonan syndrome. In contrast, other Noonan syndrome Ras mutants-V14I, T58I, and G60E-populate their active form by deregulation of the previously documented Ras GTPase activities. We propose a novel mechanism responsible for the deregulation of SOS autoactivation, where I24N, T50I, V152G, and D153V Ras mutants evade SOS autoinhibition. Consequently, they are capable of forming a complex with the SOS allosteric site, thus aberrantly promoting SOS autoactivation, resulting in the population of active Ras mutants in cells. The results of this study elucidate the molecular mechanism of the Ras mutant-mediated development of Noonan syndrome.
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Affiliation(s)
- Hope Gloria Umutesi
- Department of Chemistry and Biochemistry, University of Texas, Arlington, Texas, USA
| | - Hanh My Hoang
- Department of Chemistry and Biochemistry, University of Texas, Arlington, Texas, USA
| | | | - Kwangho Nam
- Department of Chemistry and Biochemistry, University of Texas, Arlington, Texas, USA
| | - Jongyun Heo
- Department of Chemistry and Biochemistry, University of Texas, Arlington, Texas, USA.
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19
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Myers DR, Wheeler B, Roose JP. mTOR and other effector kinase signals that impact T cell function and activity. Immunol Rev 2020; 291:134-153. [PMID: 31402496 DOI: 10.1111/imr.12796] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2019] [Accepted: 07/11/2019] [Indexed: 12/27/2022]
Abstract
T cells play important roles in autoimmune diseases and cancer. Following the cloning of the T cell receptor (TCR), the race was on to map signaling proteins that contributed to T cell activation downstream of the TCR as well as co-stimulatory molecules such as CD28. We term this "canonical TCR signaling" here. More recently, it has been appreciated that T cells need to accommodate increased metabolic needs that stem from T cell activation in order to function properly. A central role herein has emerged for mechanistic/mammalian target of rapamycin (mTOR). In this review we briefly cover canonical TCR signaling to set the stage for discussion on mTOR signaling, mRNA translation, and metabolic adaptation in T cells. We also discuss the role of mTOR in follicular helper T cells, regulatory T cells, and other T cell subsets. Our lab recently uncovered that "tonic signals", which pass through proximal TCR signaling components, are robustly and selectively transduced to mTOR to promote baseline translation of various mRNA targets. We discuss insights on (tonic) mTOR signaling in the context of T cell function in autoimmune diseases such as lupus as well as in cancer immunotherapy through CAR-T cell or checkpoint blockade approaches.
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Affiliation(s)
- Darienne R Myers
- Department of Anatomy, University of California, San Francisco, San Francisco, CA, USA
| | - Benjamin Wheeler
- Department of Anatomy, University of California, San Francisco, San Francisco, CA, USA
| | - Jeroen P Roose
- Department of Anatomy, University of California, San Francisco, San Francisco, CA, USA
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20
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Luo L, Curson JEB, Liu L, Wall AA, Tuladhar N, Lucas RM, Sweet MJ, Stow JL. SCIMP is a universal Toll‐like receptor adaptor in macrophages. J Leukoc Biol 2019; 107:251-262. [DOI: 10.1002/jlb.2ma0819-138rr] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2019] [Revised: 08/19/2019] [Accepted: 08/20/2019] [Indexed: 02/06/2023] Open
Affiliation(s)
- Lin Luo
- Institute for Molecular Bioscience (IMB) and IMB Centre for Inflammation and Disease Research The University of Queensland Brisbane Queensland Australia
| | - James E. B. Curson
- Institute for Molecular Bioscience (IMB) and IMB Centre for Inflammation and Disease Research The University of Queensland Brisbane Queensland Australia
| | - Liping Liu
- Institute for Molecular Bioscience (IMB) and IMB Centre for Inflammation and Disease Research The University of Queensland Brisbane Queensland Australia
| | - Adam A. Wall
- Institute for Molecular Bioscience (IMB) and IMB Centre for Inflammation and Disease Research The University of Queensland Brisbane Queensland Australia
| | - Neeraj Tuladhar
- Institute for Molecular Bioscience (IMB) and IMB Centre for Inflammation and Disease Research The University of Queensland Brisbane Queensland Australia
| | - Richard M. Lucas
- Institute for Molecular Bioscience (IMB) and IMB Centre for Inflammation and Disease Research The University of Queensland Brisbane Queensland Australia
| | - Matthew J. Sweet
- Institute for Molecular Bioscience (IMB) and IMB Centre for Inflammation and Disease Research The University of Queensland Brisbane Queensland Australia
| | - Jennifer L. Stow
- Institute for Molecular Bioscience (IMB) and IMB Centre for Inflammation and Disease Research The University of Queensland Brisbane Queensland Australia
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21
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Andreotti AH, Joseph RE, Conley JM, Iwasa J, Berg LJ. Multidomain Control Over TEC Kinase Activation State Tunes the T Cell Response. Annu Rev Immunol 2019; 36:549-578. [PMID: 29677469 DOI: 10.1146/annurev-immunol-042617-053344] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Signaling through the T cell antigen receptor (TCR) activates a series of tyrosine kinases. Directly associated with the TCR, the SRC family kinase LCK and the SYK family kinase ZAP-70 are essential for all downstream responses to TCR stimulation. In contrast, the TEC family kinase ITK is not an obligate component of the TCR cascade. Instead, ITK functions as a tuning dial, to translate variations in TCR signal strength into differential programs of gene expression. Recent insights into TEC kinase structure have provided a view into the molecular mechanisms that generate different states of kinase activation. In resting lymphocytes, TEC kinases are autoinhibited, and multiple interactions between the regulatory and kinase domains maintain low activity. Following TCR stimulation, newly generated signaling modules compete with the autoinhibited core and shift the conformational ensemble to the fully active kinase. This multidomain control over kinase activation state provides a structural mechanism to account for ITK's ability to tune the TCR signal.
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Affiliation(s)
- Amy H Andreotti
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa 50011, USA; ,
| | - Raji E Joseph
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa 50011, USA; ,
| | - James M Conley
- Department of Pathology, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA; ,
| | - Janet Iwasa
- Department of Biochemistry, University of Utah, Salt Lake City, Utah 84112, USA;
| | - Leslie J Berg
- Department of Pathology, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA; ,
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22
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Jun JE, Kulhanek KR, Chen H, Chakraborty A, Roose JP. Alternative ZAP70-p38 signals prime a classical p38 pathway through LAT and SOS to support regulatory T cell differentiation. Sci Signal 2019; 12:12/591/eaao0736. [PMID: 31337738 DOI: 10.1126/scisignal.aao0736] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
T cell receptor (TCR) stimulation activates diverse kinase pathways, which include the mitogen-activated protein kinases (MAPKs) ERK and p38, the phosphoinositide 3-kinases (PI3Ks), and the kinase mTOR. Although TCR stimulation activates the p38 pathway through a "classical" MAPK cascade that is mediated by the adaptor protein LAT, it also stimulates an "alternative" pathway in which p38 is activated by the kinase ZAP70. Here, we used dual-parameter, phosphoflow cytometry and in silico computation to investigate how both classical and alternative p38 pathways contribute to T cell activation. We found that basal ZAP70 activation in resting T cell lines reduced the threshold ("primed") TCR-stimulated activation of the classical p38 pathway. Classical p38 signals were reduced after T cell-specific deletion of the guanine nucleotide exchange factors Sos1 and Sos2, which are essential LAT signalosome components. As a consequence of Sos1/2 deficiency, production of the cytokine IL-2 was impaired, differentiation into regulatory T cells was reduced, and the autoimmune disease EAE was exacerbated in mice. These data suggest that the classical and alternative p38 activation pathways exist to generate immune balance.
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Affiliation(s)
- Jesse E Jun
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Kayla R Kulhanek
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Hang Chen
- Departments of Chemical Engineering, Chemistry, and Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Arup Chakraborty
- Departments of Chemical Engineering, Chemistry, and Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Jeroen P Roose
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94143, USA.
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23
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Abstract
Son of Sevenless (SOS), one of guanine nucleotide exchange factors (GEFs), activates Ras. We discovered that the allosteric domain of SOS yields SOS to proceed a previously unrecognized autoactivation kinetics. Its essential feature is a time-dependent acceleration of SOS feedback activation with a reaction initiator or with the priming of active Ras. Thus, this mechanistic autoactivation feature explains the notion, previously only conjectured, of accelerative SOS activation followed by the priming of active Ras, an action produced by another GEF Ras guanyl nucleotide-releasing protein (RasGRP). Intriguingly, the kinetic transition from gradual RasGRP activation to accelerative SOS activation has been interpreted as an analog to digital conversion; however, from the perspective of autoactivation kinetics, it is a process of straightforward RasGRP-mediated SOS autoactivation. From the viewpoint of allosteric protein cooperativity, SOS autoactivation is a unique time-dependent cooperative SOS activation because it enables an active SOS to accelerate activation of other SOS as a function of time. This time-dependent SOS cooperativity does not belong to the classic steady-state protein cooperativity, which depends on ligand concentration. Although its hysteretic or sigmoid-like saturation curvature is a classic hallmark of steady-state protein cooperativity, its hyperbolic saturation figure typically represents protein noncooperativity. We also discovered that SOS autoactivation perturbs the previously predicted hysteresis of SOS activation in a steady state to produce a hyperbolic saturation curve. We interpret this as showing that SOS allostery elicits, through SOS autoactivation, cooperativity uniquely time-dependent but not ligand concentration dependent.
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Affiliation(s)
- Hanh My Hoang
- Department of Chemistry and Biochemistry, The University of Texas at Arlington , Arlington, TX, USA
| | - Hope Gloria Umutesi
- Department of Chemistry and Biochemistry, The University of Texas at Arlington , Arlington, TX, USA
| | - Jongyun Heo
- Department of Chemistry and Biochemistry, The University of Texas at Arlington , Arlington, TX, USA
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24
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Bandaru P, Kondo Y, Kuriyan J. The Interdependent Activation of Son-of-Sevenless and Ras. Cold Spring Harb Perspect Med 2019; 9:cshperspect.a031534. [PMID: 29610148 DOI: 10.1101/cshperspect.a031534] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The guanine-nucleotide exchange factor (GEF) Son-of-Sevenless (SOS) plays a critical role in metazoan signaling by converting Ras•GDP (guanosine diphosphate) to Ras•GTP (guanosine triphosphate) in response to tyrosine kinase activation. Structural studies have shown that SOS differs from other Ras-specific GEFs in that SOS is itself activated by Ras•GTP binding to an allosteric site, distal to the site of nucleotide exchange. The activation of SOS involves membrane recruitment and conformational changes, triggered by lipid binding, that open the allosteric binding site for Ras•GTP. This is in contrast to other Ras-specific GEFs, which are activated by second messengers that more directly affect the active site. Allosteric Ras•GTP binding stabilizes SOS at the membrane, where it can turn over other Ras molecules processively, leading to an ultrasensitive response that is distinct from that of other Ras-specific GEFs.
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Affiliation(s)
- Pradeep Bandaru
- Department of Molecular and Cell Biology, California Institute for Quantitative Biosciences, Howard Hughes Medical Institute, University of California, Berkeley, California 94720
| | - Yasushi Kondo
- Department of Molecular and Cell Biology, California Institute for Quantitative Biosciences, Howard Hughes Medical Institute, University of California, Berkeley, California 94720
| | - John Kuriyan
- Departments of Molecular and Cell Biology and of Chemistry, California Institute for Quantitative Biosciences, Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Howard Hughes Medical Institute, University of California, Berkeley, California 94720
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25
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26
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Deciphering T Cell Immunometabolism with Activity-Based Protein Profiling. Curr Top Microbiol Immunol 2018; 420:175-210. [PMID: 30128827 DOI: 10.1007/82_2018_124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
Abstract
As a major sentinel of adaptive immunity, T cells seek and destroy diseased cells using antigen recognition to achieve molecular specificity. Strategies to block checkpoint inhibition of T cell activity and thus reawaken the patient's antitumor immune responses are rapidly becoming standard of care for treatment of diverse cancers. Adoptive transfer of patient T cells genetically engineered with tumor-targeting capabilities is redefining the field of personalized medicines. The diverse opportunities for exploiting T cell biology in the clinic have prompted new efforts to expand the scope of targets amenable to immuno-oncology. Given the complex spatiotemporal regulation of T cell function and fate, new technologies capable of global molecular profiling in vivo are needed to guide selection of appropriate T cell targets and subsets. In this chapter, we describe the use of activity-based protein profiling (ABPP) to illuminate different aspects of T cell metabolism and signaling as fertile starting points for investigation. We highlight the merits of ABPP methods to enable target, inhibitor, and biochemical pathway discovery of T cells in the burgeoning field of immuno-oncology.
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27
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Somekh I, Marquardt B, Liu Y, Rohlfs M, Hollizeck S, Karakukcu M, Unal E, Yilmaz E, Patiroglu T, Cansever M, Frizinsky S, Vishnvenska-Dai V, Rechavi E, Stauber T, Simon AJ, Lev A, Klein C, Kotlarz D, Somech R. Novel Mutations in RASGRP1 are Associated with Immunodeficiency, Immune Dysregulation, and EBV-Induced Lymphoma. J Clin Immunol 2018; 38:699-710. [DOI: 10.1007/s10875-018-0533-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 07/09/2018] [Indexed: 12/25/2022]
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28
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Novel insights into the pathogenesis of T-cell lymphomas. Blood 2018; 131:2320-2330. [DOI: 10.1182/blood-2017-11-764357] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Accepted: 04/09/2018] [Indexed: 12/11/2022] Open
Abstract
Abstract
T-cell lymphomas are a heterogeneous group of rare malignancies with overlapping clinical, immunologic, and histologic features. Recent advances in our understanding of T-cell differentiation based on gene expression profiling, next-generation sequencing, and transgenic mouse modeling studies have better elucidated the pathogenetic mechanisms underlying the diverse biology of T-cell lymphomas. These studies show that although genetic alterations in epigenetic modifiers are implicated in all subtypes of T-cell lymphomas, specific subtypes demonstrate enrichment for particular recurrent alterations targeting specific genes. In this regard, RHOA and TET2 alterations are prevalent in nodal T-cell lymphomas, particularly angioimmunoblastic T-cell lymphomas, peripheral T-cell lymphomas (PTCLs) not otherwise specified, and nodal PTCLs with T-follicular helper phenotype. JAK-STAT signaling pathways are mutationally activated in many extranodal T-cell lymphomas, such as natural killer/T-cell and hepatosplenic T-cell lymphomas. The functional significance of many of these genetic alterations is becoming better understood. Altogether these advances will continue to refine diagnostic criteria, improve prognostication, and identify novel therapeutic targets, resulting in improved outcomes for patient with T-cell lymphomas.
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29
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Vercoulen Y, Kondo Y, Iwig JS, Janssen AB, White KA, Amini M, Barber DL, Kuriyan J, Roose JP. A Histidine pH sensor regulates activation of the Ras-specific guanine nucleotide exchange factor RasGRP1. eLife 2017; 6:29002. [PMID: 28952923 PMCID: PMC5643099 DOI: 10.7554/elife.29002] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Accepted: 09/05/2017] [Indexed: 02/04/2023] Open
Abstract
RasGRPs are guanine nucleotide exchange factors that are specific for Ras or Rap, and are important regulators of cellular signaling. Aberrant expression or mutation of RasGRPs results in disease. An analysis of RasGRP1 SNP variants led to the conclusion that the charge of His 212 in RasGRP1 alters signaling activity and plasma membrane recruitment, indicating that His 212 is a pH sensor that alters the balance between the inactive and active forms of RasGRP1. To understand the structural basis for this effect we compared the structure of autoinhibited RasGRP1, determined previously, to those of active RasGRP4:H-Ras and RasGRP2:Rap1b complexes. The transition from the autoinhibited to the active form of RasGRP1 involves the rearrangement of an inter-domain linker that displaces inhibitory inter-domain interactions. His 212 is located at the fulcrum of these conformational changes, and structural features in its vicinity are consistent with its function as a pH-dependent switch.
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Affiliation(s)
- Yvonne Vercoulen
- Department of Anatomy, University of California, San Francisco, San Francisco, United States.,Molecular Cancer Research, Center for Molecular Medicine, UMC Utrecht, Utrecht University, Utrecht, Netherlands
| | - Yasushi Kondo
- Department of Molecular and Cell Biology and Chemistry, University of California, Berkeley, United States.,California Institute for Quantitative Biosciences, University of California, Berkeley, United States
| | - Jeffrey S Iwig
- Department of Molecular and Cell Biology and Chemistry, University of California, Berkeley, United States.,California Institute for Quantitative Biosciences, University of California, Berkeley, United States
| | - Axel B Janssen
- Department of Anatomy, University of California, San Francisco, San Francisco, United States
| | - Katharine A White
- Department of Cell and Tissue Biology, University of California, San Francisco, San Francisco, United States
| | - Mojtaba Amini
- Molecular Cancer Research, Center for Molecular Medicine, UMC Utrecht, Utrecht University, Utrecht, Netherlands
| | - Diane L Barber
- Department of Cell and Tissue Biology, University of California, San Francisco, San Francisco, United States
| | - John Kuriyan
- Department of Molecular and Cell Biology and Chemistry, University of California, Berkeley, United States.,California Institute for Quantitative Biosciences, University of California, Berkeley, United States.,Howard Hughes Medical Institute, University of California, Berkeley, United States.,Department of Chemistry, University of California, Berkeley, United States.,Divisions of Molecular Biophysics and Integrated Bioimaging, Lawrence Berkeley National Laboratory, Berkeley, United States
| | - Jeroen P Roose
- Department of Anatomy, University of California, San Francisco, San Francisco, United States
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30
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Boudjadi S, Bernatchez G, Sénicourt B, Beauséjour M, Vachon PH, Carrier JC, Beaulieu JF. Involvement of the Integrin α1β1 in the Progression of Colorectal Cancer. Cancers (Basel) 2017; 9:cancers9080096. [PMID: 28933766 PMCID: PMC5575599 DOI: 10.3390/cancers9080096] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 07/18/2017] [Accepted: 07/21/2017] [Indexed: 01/08/2023] Open
Abstract
Integrins are a family of heterodimeric glycoproteins involved in bidirectional cell signaling that participate in the regulation of cell shape, adhesion, migration, survival and proliferation. The integrin α1β1 is known to be involved in RAS/ERK proliferative pathway activation and plays an important role in fibroblast proliferation. In the small intestine, the integrin α1 subunit is present in the crypt proliferative compartment and absent in the villus. We have recently shown that the integrin α1 protein and transcript (ITGA1) are present in a large proportion of colorectal cancers (CRC) and that their expression is controlled by the MYC oncogenic factor. Considering that α1 subunit/ITGA1 expression is correlated with MYC in more than 70% of colon adenocarcinomas, we postulated that the integrin α1β1 has a pro-tumoral contribution to CRC. In HT29, T84 and SW480 CRC cells, α1 subunit/ITGA1 knockdown resulted in a reduction of cell proliferation associated with an impaired resistance to anoikis and an altered cell migration in HT29 and T84 cells. Moreover, tumor development in xenografts was reduced in HT29 and T84 sh-ITGA1 cells, associated with extensive necrosis, a low mitotic index and a reduced number of blood vessels. Our results show that α1β1 is involved in tumor cell proliferation, survival and migration. This finding suggests that α1β1 contributes to CRC progression.
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Affiliation(s)
- Salah Boudjadi
- Laboratory of Intestinal Physiopathology, Department of Anatomy and Cell Biology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC J1H 5N4, Canada.
| | - Gérald Bernatchez
- Department of Medicine, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC J1E 4K8, Canada.
| | - Blanche Sénicourt
- Laboratory of Intestinal Physiopathology, Department of Anatomy and Cell Biology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC J1H 5N4, Canada.
| | - Marco Beauséjour
- Laboratory of Intestinal Physiopathology, Department of Anatomy and Cell Biology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC J1H 5N4, Canada.
| | - Pierre H Vachon
- Laboratory of Intestinal Physiopathology, Department of Anatomy and Cell Biology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC J1H 5N4, Canada.
| | - Julie C Carrier
- Department of Medicine, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC J1E 4K8, Canada.
| | - Jean-François Beaulieu
- Laboratory of Intestinal Physiopathology, Department of Anatomy and Cell Biology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC J1H 5N4, Canada.
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31
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Termini CM, Gillette JM. Tetraspanins Function as Regulators of Cellular Signaling. Front Cell Dev Biol 2017; 5:34. [PMID: 28428953 PMCID: PMC5382171 DOI: 10.3389/fcell.2017.00034] [Citation(s) in RCA: 166] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Accepted: 03/22/2017] [Indexed: 01/10/2023] Open
Abstract
Tetraspanins are molecular scaffolds that distribute proteins into highly organized microdomains consisting of adhesion, signaling, and adaptor proteins. Many reports have identified interactions between tetraspanins and signaling molecules, finding unique downstream cellular consequences. In this review, we will explore these interactions as well as the specific cellular responses to signal activation, focusing on tetraspanin regulation of adhesion-mediated (integrins/FAK), receptor-mediated (EGFR, TNF-α, c-Met, c-Kit), and intracellular signaling (PKC, PI4K, β-catenin). Additionally, we will summarize our current understanding for how tetraspanin post-translational modifications (palmitoylation, N-linked glycosylation, and ubiquitination) can regulate signal propagation. Many of the studies outlined in this review suggest that tetraspanins offer a potential therapeutic target to modulate aberrant signal transduction pathways that directly impact a host of cellular behaviors and disease states.
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Affiliation(s)
- Christina M Termini
- Department of Pathology, University of New Mexico Health Sciences CenterAlbuquerque, NM, USA
| | - Jennifer M Gillette
- Department of Pathology, University of New Mexico Health Sciences CenterAlbuquerque, NM, USA
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32
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Guittard G, Gallardo DL, Li W, Melis N, Lui JC, Kortum RL, Shakarishvili NG, Huh S, Baron J, Weigert R, Kramer JA, Samelson LE, Sommers CL. Unexpected Cartilage Phenotype in CD4-Cre-Conditional SOS-Deficient Mice. Front Immunol 2017; 8:343. [PMID: 28386265 PMCID: PMC5362643 DOI: 10.3389/fimmu.2017.00343] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 03/10/2017] [Indexed: 12/11/2022] Open
Abstract
RAS signaling is central to many cellular processes and SOS proteins promote RAS activation. To investigate the role of SOS proteins in T cell biology, we crossed Sos1f/fSos2−/− mice to CD4-Cre transgenic mice. We previously reported an effect of these mutations on T cell signaling and T cell migration. Unexpectedly, we observed nodules on the joints of greater than 90% of these mutant mice at 5 months of age, especially on the carpal joints. As the mice aged further, some also displayed joint stiffness, hind limb paralysis, and lameness. Histological analysis indicated that the abnormal growth in joints originated from dysplastic chondrocytes. Second harmonic generation imaging of the carpal nodules revealed that nodules were encased by rich collagen fibrous networks. Nodules formed in mice also deficient in RAG2, indicating that conventional T cells, which undergo rearrangement of the T cell antigen receptor, are not required for this phenotype. CD4-Cre expression in a subset of cells, either immune lineage cells (e.g., non-conventional T cells) or non-immune lineage cells (e.g., chondrocytes) likely mediates the dramatic phenotype observed in this study. Disruptions of genes in the RAS signaling pathway are especially likely to cause this phenotype. These results also serve as a cautionary tale to those intending to use CD4-Cre transgenic mice to specifically delete genes in conventional T cells.
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Affiliation(s)
- Geoffrey Guittard
- Laboratory of Cellular and Molecular Biology, CCR, NCI, NIH , Bethesda, MD , USA
| | - Devorah L Gallardo
- Laboratory Animal Sciences Program, Leidos Biomedical Research, NCI, NIH , Bethesda, MD , USA
| | - Wenmei Li
- Laboratory of Cellular and Molecular Biology, CCR, NCI, NIH , Bethesda, MD , USA
| | - Nicolas Melis
- Laboratory of Cellular and Molecular Biology, CCR, NCI, NIH , Bethesda, MD , USA
| | - Julian C Lui
- Section on Growth and Development, NICHD, NIH , Bethesda, MD , USA
| | - Robert L Kortum
- Department of Pharmacology, Uniformed Services University of the Health Sciences , Bethesda, MD , USA
| | | | - Sunmee Huh
- Laboratory of Cellular and Molecular Biology, CCR, NCI, NIH , Bethesda, MD , USA
| | - Jeffrey Baron
- Section on Growth and Development, NICHD, NIH , Bethesda, MD , USA
| | - Roberto Weigert
- Laboratory of Cellular and Molecular Biology, CCR, NCI, NIH , Bethesda, MD , USA
| | - Joshua A Kramer
- Laboratory Animal Sciences Program, Leidos Biomedical Research, NCI, NIH , Bethesda, MD , USA
| | - Lawrence E Samelson
- Laboratory of Cellular and Molecular Biology, CCR, NCI, NIH , Bethesda, MD , USA
| | - Connie L Sommers
- Laboratory of Cellular and Molecular Biology, CCR, NCI, NIH , Bethesda, MD , USA
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33
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Vacaflores A, Freedman SN, Chapman NM, Houtman JCD. Pretreatment of activated human CD8 T cells with IL-12 leads to enhanced TCR-induced signaling and cytokine production. Mol Immunol 2016; 81:1-15. [PMID: 27883938 DOI: 10.1016/j.molimm.2016.11.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Revised: 10/21/2016] [Accepted: 11/14/2016] [Indexed: 10/24/2022]
Abstract
During the immune response to pathogens and autoantigens, CD8T cells are exposed to numerous inflammatory agents including the cytokine IL-12. Previous studies have focused on how IL-12 regulates T cell functions when present during or after the activation of the T cell receptor (TCR). However, recent studies suggest that prior exposure to IL-12 also alters the TCR responsiveness of murine T cells. Whether similar phenomena occur in human activated CD8T cells and the mechanisms mediating these effects remain unexplored. In this study, we observed that pretreatment of human activated CD8T cells with IL-12 results in increased cytokine mRNA and protein production following subsequent TCR challenge. The potentiation of TCR-mediated cytokine release was transient and required low doses of IL-12 for at least 24h. Mechanistically, prior exposure to IL-12 increased the TCR induced activation of select MAPKs and AKT without altering the activation of more proximal TCR signaling molecules, suggesting that the IL-12 mediated changes in TCR signaling are responsible for the increased production of cytokines. Our data suggest that prior treatment with IL-12 potentiates human CD8T cell responses at sites of infection and inflammation, expanding our understanding of the function of this clinically important cytokine.
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Affiliation(s)
- Aldo Vacaflores
- Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA 52242, United States
| | - Samantha N Freedman
- Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA 52242, United States
| | - Nicole M Chapman
- Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA 52242, United States
| | - Jon C D Houtman
- Interdisciplinary Graduate Program in Immunology, University of Iowa, Iowa City, IA 52242, United States; Department of Microbiology, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, United States; Department of Internal Medicine, Division of Immunology, University of Iowa, Iowa City, IA 52242, United States.
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34
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Brock EJ, Ji K, Reiners JJ, Mattingly RR. How to Target Activated Ras Proteins: Direct Inhibition vs. Induced Mislocalization. Mini Rev Med Chem 2016; 16:358-69. [PMID: 26423696 DOI: 10.2174/1389557515666151001154002] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Revised: 09/03/2015] [Accepted: 09/18/2015] [Indexed: 12/13/2022]
Abstract
Oncogenic Ras proteins are a driving force in a significant set of human cancers and wildtype, unmutated Ras proteins likely contribute to the malignant phenotype of many more. The overall challenge of targeting activated Ras proteins has great promise to treat cancer, but this goal has yet to be achieved. Significant efforts and resources have been committed to inhibiting Ras, but these energies have so far made little impact in the clinic. Direct attempts to target activated Ras proteins have faced many obstacles, including the fundamental nature of the gain-of-function oncogenic activity being produced by a loss-of-function at the biochemical level. Nevertheless, there has been very promising recent pre-clinical progress. The major strategy that has so far reached the clinic aimed to inhibit activated Ras indirectly through blocking its post-translational modification and inducing its mislocalization. While these efforts to indirectly target Ras through inhibition of farnesyl transferase (FTase) were rationally designed, this strategy suffered from insufficient attention to the distinctions between the isoforms of Ras. This led to subsequent failures in large-scale clinical trials targeting K-Ras driven lung, colon, and pancreatic cancers. Despite these setbacks, efforts to indirectly target activated Ras through inducing its mislocalization have persisted. It is plausible that FTase inhibitors may still have some utility in the clinic, perhaps in combination with statins or other agents. Alternative approaches for inducing mislocalization of Ras through disruption of its palmitoylation cycle or interaction with chaperone proteins are in early stages of development.
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Affiliation(s)
| | | | | | - Raymond R Mattingly
- Department of Pharmacology, Wayne State University School of Medicine, 540 East Canfield Ave, Detroit MI, USA.
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35
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Salzer E, Cagdas D, Hons M, Mace EM, Garncarz W, Petronczki ÖY, Platzer R, Pfajfer L, Bilic I, Ban SA, Willmann KL, Mukherjee M, Supper V, Hsu HT, Banerjee PP, Sinha P, McClanahan F, Zlabinger GJ, Pickl WF, Gribben JG, Stockinger H, Bennett KL, Huppa JB, Dupré L, Sanal Ö, Jäger U, Sixt M, Tezcan I, Orange JS, Boztug K. RASGRP1 deficiency causes immunodeficiency with impaired cytoskeletal dynamics. Nat Immunol 2016; 17:1352-1360. [PMID: 27776107 DOI: 10.1038/ni.3575] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 09/01/2016] [Indexed: 12/15/2022]
Abstract
RASGRP1 is an important guanine nucleotide exchange factor and activator of the RAS-MAPK pathway following T cell antigen receptor (TCR) signaling. The consequences of RASGRP1 mutations in humans are unknown. In a patient with recurrent bacterial and viral infections, born to healthy consanguineous parents, we used homozygosity mapping and exome sequencing to identify a biallelic stop-gain variant in RASGRP1. This variant segregated perfectly with the disease and has not been reported in genetic databases. RASGRP1 deficiency was associated in T cells and B cells with decreased phosphorylation of the extracellular-signal-regulated serine kinase ERK, which was restored following expression of wild-type RASGRP1. RASGRP1 deficiency also resulted in defective proliferation, activation and motility of T cells and B cells. RASGRP1-deficient natural killer (NK) cells exhibited impaired cytotoxicity with defective granule convergence and actin accumulation. Interaction proteomics identified the dynein light chain DYNLL1 as interacting with RASGRP1, which links RASGRP1 to cytoskeletal dynamics. RASGRP1-deficient cells showed decreased activation of the GTPase RhoA. Treatment with lenalidomide increased RhoA activity and reversed the migration and activation defects of RASGRP1-deficient lymphocytes.
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Affiliation(s)
- Elisabeth Salzer
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria.,Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, Vienna, Austria
| | - Deniz Cagdas
- Section of Pediatric Immunology, Hacettepe University, Ihsan Dogramaci Children's Hospital, Ankara, Turkey
| | - Miroslav Hons
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Emily M Mace
- Center for Human Immunobiology, Baylor College of Medicine and Texas Children's Hospital, Houston, Texas, USA
| | - Wojciech Garncarz
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria.,Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, Vienna, Austria
| | - Özlem Yüce Petronczki
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria.,Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, Vienna, Austria
| | - René Platzer
- Institute for Hygiene and Applied Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Laurène Pfajfer
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria.,Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, Vienna, Austria
| | - Ivan Bilic
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Sol A Ban
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Katharina L Willmann
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Malini Mukherjee
- Center for Human Immunobiology, Baylor College of Medicine and Texas Children's Hospital, Houston, Texas, USA
| | - Verena Supper
- Institute for Hygiene and Applied Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Hsiang Ting Hsu
- Center for Human Immunobiology, Baylor College of Medicine and Texas Children's Hospital, Houston, Texas, USA
| | - Pinaki P Banerjee
- Center for Human Immunobiology, Baylor College of Medicine and Texas Children's Hospital, Houston, Texas, USA
| | - Papiya Sinha
- Center for Human Immunobiology, Baylor College of Medicine and Texas Children's Hospital, Houston, Texas, USA
| | - Fabienne McClanahan
- Centre for Haemato-Oncology, Barts Cancer Institute - a CR-UK Centre of Excellence, Queen Mary University of London, London, UK
| | - Gerhard J Zlabinger
- Institute of Immunology, Center of Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Winfried F Pickl
- Christian Doppler Laboratory for Immunomodulation and Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - John G Gribben
- Centre for Haemato-Oncology, Barts Cancer Institute - a CR-UK Centre of Excellence, Queen Mary University of London, London, UK
| | - Hannes Stockinger
- Institute for Hygiene and Applied Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Keiryn L Bennett
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria
| | - Johannes B Huppa
- Institute for Hygiene and Applied Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Loïc Dupré
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria.,Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, Vienna, Austria.,Centre de Physiopathologie de Toulouse Purpan (CPTP), INSERM, UMR1043, Toulouse Purpan University Hospital, Toulouse, France
| | - Özden Sanal
- Section of Pediatric Immunology, Hacettepe University, Ihsan Dogramaci Children's Hospital, Ankara, Turkey
| | - Ulrich Jäger
- Department of Medicine I, Division of Hematology and Hemostaseology, Medical University of Vienna, Vienna, Austria
| | - Michael Sixt
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Ilhan Tezcan
- Section of Pediatric Immunology, Hacettepe University, Ihsan Dogramaci Children's Hospital, Ankara, Turkey
| | - Jordan S Orange
- Center for Human Immunobiology, Baylor College of Medicine and Texas Children's Hospital, Houston, Texas, USA
| | - Kaan Boztug
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria.,Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, Vienna, Austria.,Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria.,St. Anna Kinderspital and Children's Cancer Research Institute, Department of Pediatrics, Medical University of Vienna, Vienna, Austria
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36
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Christensen SM, Tu HL, Jun JE, Alvarez S, Triplet MG, Iwig JS, Yadav KK, Bar-Sagi D, Roose JP, Groves JT. One-way membrane trafficking of SOS in receptor-triggered Ras activation. Nat Struct Mol Biol 2016; 23:838-46. [PMID: 27501536 PMCID: PMC5016256 DOI: 10.1038/nsmb.3275] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 07/08/2016] [Indexed: 02/07/2023]
Abstract
SOS is a key activator of the small GTPase Ras. In cells, SOS-Ras signaling is thought to be initiated predominantly by membrane recruitment of SOS via the adaptor Grb2 and balanced by rapidly reversible Grb2-SOS binding kinetics. However, SOS has multiple protein and lipid interactions that provide linkage to the membrane. In reconstituted-membrane experiments, these Grb2-independent interactions were sufficient to retain human SOS on the membrane for many minutes, during which a single SOS molecule could processively activate thousands of Ras molecules. These observations raised questions concerning how receptors maintain control of SOS in cells and how membrane-recruited SOS is ultimately released. We addressed these questions in quantitative assays of reconstituted SOS-deficient chicken B-cell signaling systems combined with single-molecule measurements in supported membranes. These studies revealed an essentially one-way trafficking process in which membrane-recruited SOS remains trapped on the membrane and continuously activates Ras until being actively removed via endocytosis.
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Affiliation(s)
- Sune M. Christensen
- Department of Chemistry, University of California, Berkeley, California, USA
| | - Hsiung-Lin Tu
- Department of Chemistry, University of California, Berkeley, California, USA
| | - Jesse E. Jun
- Department of Anatomy, University of California, San Francisco, California, USA
| | - Steven Alvarez
- Department of Chemistry, University of California, Berkeley, California, USA
| | - Meredith G. Triplet
- Department of Chemistry, University of California, Berkeley, California, USA
| | - Jeffrey S. Iwig
- Howard Hughes Medical Institute, Department of Molecular and Cell Biology, University of California, Berkeley, California, USA
| | - Kamlesh K. Yadav
- Department of Biochemistry, New York University School of Medicine, New York, USA
| | - Dafna Bar-Sagi
- Department of Biochemistry, New York University School of Medicine, New York, USA
| | - Jeroen P. Roose
- Department of Anatomy, University of California, San Francisco, California, USA
| | - Jay T. Groves
- Department of Chemistry, University of California, Berkeley, California, USA
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Kralova J, Fabisik M, Pokorna J, Skopcova T, Malissen B, Brdicka T. The Transmembrane Adaptor Protein SCIMP Facilitates Sustained Dectin-1 Signaling in Dendritic Cells. J Biol Chem 2016; 291:16530-40. [PMID: 27288407 DOI: 10.1074/jbc.m116.717157] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Indexed: 11/06/2022] Open
Abstract
Transmembrane adaptor proteins are molecules specialized in recruiting cytoplasmic proteins to the proximity of the cell membrane as part of the signal transduction process. A member of this family, SLP65/SLP76, Csk-interacting membrane protein (SCIMP), recruits a complex of SLP65/SLP76 and Grb2 adaptor proteins, known to be involved in the activation of PLCγ1/2, Ras, and other pathways. SCIMP expression is restricted to antigen-presenting cells. In a previous cell line-based study, it was shown that, in B cells, SCIMP contributes to the reverse signaling in the immunological synapse, downstream of MHCII glycoproteins. There it mainly facilitates the activation of ERK MAP kinases. However, its importance for MHCII glycoprotein-dependent ERK signaling in primary B cells has not been analyzed. Moreover, its role in macrophages and dendritic cells has remained largely unknown. Here we present the results of our analysis of SCIMP-deficient mice. In these mice, we did not observe any defects in B cell signaling and B cell-dependent responses. On the other hand, we found that, in dendritic cells and macrophages, SCIMP expression is up-regulated after exposure to GM-CSF or the Dectin-1 agonist zymosan. Moreover, we found that SCIMP is strongly phosphorylated after Dectin-1 stimulation and that it participates in signal transduction downstream of this important pattern recognition receptor. Our analysis of SCIMP-deficient dendritic cells revealed that SCIMP specifically contributes to sustaining long-term MAP kinase signaling and cytokine production downstream of Dectin-1 because of an increased expression and sustained phosphorylation lasting at least 24 h after signal initiation.
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Affiliation(s)
| | | | - Jana Pokorna
- Molecular Immunology, Institute of Molecular Genetics, Academy of Sciences of the Czech Republic, 14220 Prague, Czech Republic and
| | | | - Bernard Malissen
- the Centre d'Immunophénomique, PHENOMIN-CIPHE, Aix Marseille Université UM2, INSERM US012, CNRS UMS3367, 13288 Marseille, France
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Mues M, Roose JP. Distinct oncogenic Ras signals characterized by profound differences in flux through the RasGDP/RasGTP cycle. Small GTPases 2016; 8:20-25. [PMID: 27159504 DOI: 10.1080/21541248.2016.1187323] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
T cell acute lymphoblastic leukemia/lymphoma (T-ALL) is an aggressive bone marrow cancer in children and adults, and chemotherapy often fails for relapsing patients. Molecularly targeted therapy is hindered by heterogeneity in T-ALL and mechanistic details of the affected pathways in T-ALL are needed. Deregulation of Ras signals is common in T-ALL. Ras is genetically mutated to a constitutively active form in about 15% of all haematopoietic malignancies, but there is a range of other ways to augment signaling through the Ras pathway. Several groups including our own uncovered that RasGRP1 overexpression leads to T-ALL in mouse models and in pediatric T-ALL patients, and we reported that this Ras guanine nucleotide exchange factor, RasGRP1, cooperates with cytokines to drive leukemogenesis. In our recent study by Ksionda et al. we analyzed the molecular details of cytokine receptor-RasGRP1-Ras signals in T-ALL and compared these to signals from mutated Ras alleles, which yielded several surprising results. Examples are the striking differences in flux through the RasGDP/RasGTP cycle in distinct T-ALL or unexpected differences in wiring of the Ras signaling pathway between T-ALL and normal developing T cells, which we will discuss here.
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Affiliation(s)
- Marsilius Mues
- a Department of Anatomy , University of California San Francisco , San Francisco , CA , USA
| | - Jeroen P Roose
- a Department of Anatomy , University of California San Francisco , San Francisco , CA , USA
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Owens M, Kivuva E, Quinn A, Brennan P, Caswell R, Lango Allen H, Vaidya B, Ellard S. SOS1 frameshift mutations cause pure mucosal neuroma syndrome, a clinical phenotype distinct from multiple endocrine neoplasia type 2B. Clin Endocrinol (Oxf) 2016; 84:715-9. [PMID: 26708403 DOI: 10.1111/cen.13008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 09/21/2015] [Accepted: 12/17/2015] [Indexed: 11/27/2022]
Abstract
BACKGROUND Mucosal neuromas, thickened corneal nerves and marfanoid body habitus are characteristic phenotypic features of multiple endocrine neoplasia type 2B (MEN2B) and often provide an early clue to the diagnosis of the syndrome. Rarely, patients present with typical physical features of MEN2B but without associated endocrinopathies (medullary thyroid carcinoma or pheochromocytoma) or a RET gene mutation; this clinical presentation is thought to represent a distinct condition termed 'pure mucosal neuroma syndrome'. METHODS Exome sequencing was performed in two unrelated probands with mucosal neuromas, thickened corneal nerves and marfanoid body habitus, but no MEN2B-associated endocrinopathy or RET gene mutation. Sanger sequencing was performed to confirm mutations detected by exome sequencing and to test in family members and 3 additional unrelated index patients with mucosal neuromas or thickened corneal nerves. RESULTS A heterozygous SOS1 gene frameshift mutation (c.3266dup or c.3248dup) was identified in each proband. Sanger sequencing showed that proband 1 inherited the c.3266dup mutation from his affected mother, while the c.3248dup mutation had arisen de novo in proband 2. Sanger sequencing also identified one further novel SOS1 mutation (c.3254dup) in one of the 3 additional index patients. CONCLUSION Our results demonstrate the existence of pure mucosal neuroma syndrome as a clinical entity distinct from MEN2B that can now be diagnosed by genetic testing.
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Affiliation(s)
- Martina Owens
- Department of Molecular Genetics, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
| | - Emma Kivuva
- Department of Clinical Genetics, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
| | - Anthony Quinn
- Department of Ophthalmology, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
| | - Paul Brennan
- Northern Genetics Service, Newcastle Hospitals NHS Foundation Trust, Newcastle upon Tyne, UK
| | - Richard Caswell
- Institute of Biomedical and Clinical Science, University of Exeter Medical School, Exeter, UK
| | - Hana Lango Allen
- Institute of Biomedical and Clinical Science, University of Exeter Medical School, Exeter, UK
| | - Bijay Vaidya
- Department of Diabetes and Endocrinology, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
| | - Sian Ellard
- Department of Molecular Genetics, Royal Devon and Exeter NHS Foundation Trust, Exeter, UK
- Institute of Biomedical and Clinical Science, University of Exeter Medical School, Exeter, UK
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40
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Koch D, Rai A, Ali I, Bleimling N, Friese T, Brockmeyer A, Janning P, Goud B, Itzen A, Müller MP, Goody RS. A pull-down procedure for the identification of unknown GEFs for small GTPases. Small GTPases 2016; 7:93-106. [PMID: 26918858 PMCID: PMC4905258 DOI: 10.1080/21541248.2016.1156803] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Members of the family of small GTPases regulate a variety of important cellular functions. In order to accomplish this, tight temporal and spatial regulation is absolutely necessary. The two most important factors for this regulation are GTPase activating proteins (GAPs) and guanine nucleotide exchange factors (GEFs), the latter being responsible for the activation of the GTPase downstream pathways at the correct location and time. Although a large number of exchange factors have been identified, it is likely that a similarly large number remains unidentified. We have therefore developed a procedure to specifically enrich GEF proteins from biological samples making use of the high affinity binding of GEFs to nucleotide-free GTPases. In order to verify the results of these pull-down experiments, we have additionally developed two simple validation procedures: An in vitro transcription/translation system coupled with a GEF activity assay and a yeast two-hybrid screen for detection of GEFs. Although the procedures were established and tested using the Rab protein Sec4, the similar basic principle of action of all nucleotide exchange factors will allow the method to be used for identification of unknown GEFs of small GTPases in general.
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Affiliation(s)
- Daniel Koch
- a Department of Structural Biochemistry , Max Planck Institute of Molecular Physiology , Dortmund , Germany
| | - Amrita Rai
- a Department of Structural Biochemistry , Max Planck Institute of Molecular Physiology , Dortmund , Germany
| | - Imtiaz Ali
- a Department of Structural Biochemistry , Max Planck Institute of Molecular Physiology , Dortmund , Germany
| | - Nathalie Bleimling
- a Department of Structural Biochemistry , Max Planck Institute of Molecular Physiology , Dortmund , Germany
| | - Timon Friese
- a Department of Structural Biochemistry , Max Planck Institute of Molecular Physiology , Dortmund , Germany
| | - Andreas Brockmeyer
- b Department of Chemical Biology , Max Planck Institute of Molecular Physiology , Dortmund , Germany
| | - Petra Janning
- b Department of Chemical Biology , Max Planck Institute of Molecular Physiology , Dortmund , Germany
| | - Bruno Goud
- c Institut Curie, PSL Research University, CNRS UMR 144 , Paris , France
| | - Aymelt Itzen
- d Center for Integrated Protein Science Munich (CIPSM), Department of Chemistry, Technische Universität München , Garching , Germany
| | - Matthias P Müller
- a Department of Structural Biochemistry , Max Planck Institute of Molecular Physiology , Dortmund , Germany
| | - Roger S Goody
- a Department of Structural Biochemistry , Max Planck Institute of Molecular Physiology , Dortmund , Germany
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41
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Wang J, Sun K, Shen Y, Xu Y, Xie J, Huang R, Zhang Y, Xu C, Zhang X, Wang R, Lin Y. DNA methylation is critical for tooth agenesis: implications for sporadic non-syndromic anodontia and hypodontia. Sci Rep 2016; 6:19162. [PMID: 26759063 PMCID: PMC4725352 DOI: 10.1038/srep19162] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Accepted: 12/02/2015] [Indexed: 02/05/2023] Open
Abstract
Hypodontia is caused by interactions among genetic, epigenetic, and environmental factors during tooth development, but the actual mechanism is unknown. DNA methylation now appears to play a significant role in abnormal developments, flawed phenotypes, and acquired diseases. Methylated DNA immunoprecipitation (MeDIP) has been developed as a new method of scanning large-scale DNA-methylation profiles within particular regions or in the entire genome. Here, we performed a genome-wide scan of paired DNA samples obtained from 4 patients lacking two mandibular incisors and 4 healthy controls with normal dentition. We scanned another female with non-syndromic anodontia and her younger brother with the same gene mutations of the PAX9,MSX1,AXIN2 and EDA, but without developmental abnormalities in the dentition. Results showed significant differences in the methylation level of the whole genome between the hypodontia and the normal groups. Nine genes were spotted, some of which have not been associated with dental development; these genes were related mainly to the development of cartilage, bone, teeth, and neural transduction, which implied a potential gene cascade network in hypodontia at the methylation level. This pilot study reveals the critical role of DNA methylation in hypodontia and might provide insights into developmental biology and the pathobiology of acquired diseases.
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Affiliation(s)
- Jing Wang
- Department of Stomatology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, No.301, Middle Yanchang Road, Shanghai 200072, P.R. China
| | - Ke Sun
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, No.14., 3rd Sec, Ren Min Nan Road, Chengdu 610041, P.R. China
| | - Yun Shen
- Department of Stomatology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, No.301, Middle Yanchang Road, Shanghai 200072, P.R. China
| | - Yuanzhi Xu
- Department of Stomatology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, No.301, Middle Yanchang Road, Shanghai 200072, P.R. China
| | - Jing Xie
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, No.14., 3rd Sec, Ren Min Nan Road, Chengdu 610041, P.R. China
| | - Renhuan Huang
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, No.14., 3rd Sec, Ren Min Nan Road, Chengdu 610041, P.R. China
| | - Yiming Zhang
- Department of Stomatology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, No.301, Middle Yanchang Road, Shanghai 200072, P.R. China
| | - Chenyuan Xu
- Department of Stomatology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, No.301, Middle Yanchang Road, Shanghai 200072, P.R. China
| | - Xu Zhang
- Department of Stomatology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, No.301, Middle Yanchang Road, Shanghai 200072, P.R. China
| | - Raorao Wang
- Department of Stomatology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, No.301, Middle Yanchang Road, Shanghai 200072, P.R. China
| | - Yunfeng Lin
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, No.14., 3rd Sec, Ren Min Nan Road, Chengdu 610041, P.R. China
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Sauer K, Okkenhaug K. Editorial: Lipid Signaling in T Cell Development and Function. Front Immunol 2015; 6:410. [PMID: 26322043 PMCID: PMC4530596 DOI: 10.3389/fimmu.2015.00410] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 07/27/2015] [Indexed: 11/13/2022] Open
Affiliation(s)
- Karsten Sauer
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA, USA
- Department of Cell and Molecular Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Klaus Okkenhaug
- Laboratory of Lymphocyte Signalling and Development, Babraham Institute, Cambridge, UK
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43
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Guittard G, Kortum RL, Balagopalan L, Çuburu N, Nguyen P, Sommers CL, Samelson LE. Absence of both Sos-1 and Sos-2 in peripheral CD4(+) T cells leads to PI3K pathway activation and defects in migration. Eur J Immunol 2015; 45:2389-95. [PMID: 25973715 DOI: 10.1002/eji.201445226] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Revised: 04/07/2015] [Accepted: 05/12/2015] [Indexed: 11/10/2022]
Abstract
Sos-1 and Sos-2 are ubiquitously expressed Ras-guanine exchange factors involved in Erk-MAP kinase pathway activation. Using mice lacking genes encoding Sos-1 and Sos-2, we evaluated the role of these proteins in peripheral T-cell signaling and function. Our results confirmed that TCR-mediated Erk activation in peripheral CD4(+) T cells does not depend on Sos-1 and Sos-2, although IL-2-mediated Erk activation does. Unexpectedly, however, we show an increase in AKT phosphorylation in Sos-1/2dKO CD4(+) T cells upon TCR and IL-2 stimulation. Activation of AKT was likely a consequence of increased recruitment of PI3K to Grb2 upon TCR and/or IL-2 stimulation in Sos-1/2dKO CD4(+) T cells. The increased activity of the PI3K/AKT pathway led to downregulation of the surface receptor CD62L in Sos-1/2dKO T cells and a subsequent impairment in T-cell migration.
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Affiliation(s)
- Geoffrey Guittard
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Robert L Kortum
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Lakshmi Balagopalan
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Nicolas Çuburu
- Laboratory of Cellular Oncology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Phan Nguyen
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Connie L Sommers
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Lawrence E Samelson
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
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44
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Malissen B, Grégoire C, Malissen M, Roncagalli R. Integrative biology of T cell activation. Nat Immunol 2014; 15:790-7. [PMID: 25137453 DOI: 10.1038/ni.2959] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2014] [Accepted: 07/10/2014] [Indexed: 12/11/2022]
Abstract
The activation of T cells mediated by the T cell antigen receptor (TCR) requires the interaction of dozens of proteins, and its malfunction has pathological consequences. Our major focus is on new developments in the systems-level understanding of the TCR signal-transduction network. To make sense of the formidable complexity of this network, we argue that 'fine-grained' methods are needed to assess the relationships among a few components that interact on a nanometric scale, and those should be integrated with high-throughput '-omic' approaches that simultaneously capture large numbers of parameters. We illustrate the utility of this integrative approach with the transmembrane signaling protein Lat, which is a key signaling hub of the TCR signal-transduction network, as a connecting thread.
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Affiliation(s)
- Bernard Malissen
- 1] Centre d'Immunologie de Marseille-Luminy, UM2 Aix-Marseille Université, Marseille, France. [2] INSERM U1104, Marseille, France. [3] CNRS UMR7280, Marseille, France. [4] Centre d'Immunophénomique, UM2 Aix-Marseille Université, Marseille, France. [5] INSERM US012, Marseille, France. [6] CNRS UMS3367, Marseille, France
| | - Claude Grégoire
- 1] Centre d'Immunologie de Marseille-Luminy, UM2 Aix-Marseille Université, Marseille, France. [2] INSERM U1104, Marseille, France. [3] CNRS UMR7280, Marseille, France
| | - Marie Malissen
- 1] Centre d'Immunologie de Marseille-Luminy, UM2 Aix-Marseille Université, Marseille, France. [2] INSERM U1104, Marseille, France. [3] CNRS UMR7280, Marseille, France. [4] Centre d'Immunophénomique, UM2 Aix-Marseille Université, Marseille, France. [5] INSERM US012, Marseille, France. [6] CNRS UMS3367, Marseille, France
| | - Romain Roncagalli
- 1] Centre d'Immunologie de Marseille-Luminy, UM2 Aix-Marseille Université, Marseille, France. [2] INSERM U1104, Marseille, France. [3] CNRS UMR7280, Marseille, France
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45
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Serine-threonine kinases in TCR signaling. Nat Immunol 2014; 15:808-14. [PMID: 25137455 DOI: 10.1038/ni.2941] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Accepted: 06/10/2014] [Indexed: 12/13/2022]
Abstract
T lymphocyte proliferation and differentiation are controlled by signaling pathways initiated by the T cell antigen receptor. Here we explore how key serine-threonine kinases and their substrates mediate T cell signaling and coordinate T cell metabolism to meet the metabolic demands of participating in an immune response.
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46
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Molecular mechanisms and functional implications of polarized actin remodeling at the T cell immunological synapse. Cell Mol Life Sci 2014; 72:537-556. [PMID: 25355055 DOI: 10.1007/s00018-014-1760-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 09/22/2014] [Accepted: 10/13/2014] [Indexed: 02/05/2023]
Abstract
Transient,specialized cell-cell interactions play a central role in leukocyte function by enabling specific intercellular communication in the context of a highly dynamic systems level response. The dramatic structural changes required for the formation of these contacts are driven by rapid and precise cytoskeletal remodeling events. In recent years, the immunological synapse that forms between a T lymphocyte and its antigen-presenting target cell has emerged as an important model system for understanding immune cell interactions. In this review, we discuss how regulators of the cortical actin cytoskeleton control synaptic architecture and in this way specify T cell function.
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47
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Iversen L, Tu HL, Lin WC, Christensen SM, Abel SM, Iwig J, Wu HJ, Gureasko J, Rhodes C, Petit RS, Hansen SD, Thill P, Yu CH, Stamou D, Chakraborty AK, Kuriyan J, Groves JT. Molecular kinetics. Ras activation by SOS: allosteric regulation by altered fluctuation dynamics. Science 2014; 345:50-4. [PMID: 24994643 DOI: 10.1126/science.1250373] [Citation(s) in RCA: 103] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Activation of the small guanosine triphosphatase H-Ras by the exchange factor Son of Sevenless (SOS) is an important hub for signal transduction. Multiple layers of regulation, through protein and membrane interactions, govern activity of SOS. We characterized the specific activity of individual SOS molecules catalyzing nucleotide exchange in H-Ras. Single-molecule kinetic traces revealed that SOS samples a broad distribution of turnover rates through stochastic fluctuations between distinct, long-lived (more than 100 seconds), functional states. The expected allosteric activation of SOS by Ras-guanosine triphosphate (GTP) was conspicuously absent in the mean rate. However, fluctuations into highly active states were modulated by Ras-GTP. This reveals a mechanism in which functional output may be determined by the dynamical spectrum of rates sampled by a small number of enzymes, rather than the ensemble average.
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Affiliation(s)
- Lars Iversen
- Howard Hughes Medical Institute, Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Hsiung-Lin Tu
- Howard Hughes Medical Institute, Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Wan-Chen Lin
- Howard Hughes Medical Institute, Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Sune M Christensen
- Howard Hughes Medical Institute, Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Steven M Abel
- Department of Chemical Engineering, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA
| | - Jeff Iwig
- Howard Hughes Medical Institute, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Hung-Jen Wu
- Howard Hughes Medical Institute, Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Jodi Gureasko
- Howard Hughes Medical Institute, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Christopher Rhodes
- Department of Mechanical Engineering, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Rebecca S Petit
- Howard Hughes Medical Institute, Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Scott D Hansen
- Howard Hughes Medical Institute, Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Peter Thill
- Department of Chemistry, MIT, Cambridge, MA 02139, USA
| | - Cheng-Han Yu
- Mechanobiology Institute, National University of Singapore, Singapore
| | - Dimitrios Stamou
- Department of Chemistry and Nano-Science Center, University of Copenhagen, Copenhagen, Denmark
| | - Arup K Chakraborty
- Department of Chemical Engineering, Massachusetts Institute of Technology (MIT), Cambridge, MA 02139, USA. Department of Chemistry, MIT, Cambridge, MA 02139, USA. Department of Biological Engineering, MIT, Cambridge, MA 02139, USA. Ragon Institute of Massachusetts General Hospital, MIT, and Harvard, Cambridge, MA 02139, USA. Department of Physics, MIT, Cambridge, MA 02139, USA. Institute for Medical Engineering and Science, MIT, Cambridge, MA 02139, USA
| | - John Kuriyan
- Howard Hughes Medical Institute, Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720, USA. Howard Hughes Medical Institute, Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA. Physical Biosciences and Materials Sciences Divisions, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Jay T Groves
- Howard Hughes Medical Institute, Department of Chemistry, University of California, Berkeley, Berkeley, CA 94720, USA. Mechanobiology Institute, National University of Singapore, Singapore. Physical Biosciences and Materials Sciences Divisions, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA. Berkeley Education Alliance for Research in Singapore, 1 Create Way, CREATE tower level 11, University Town, Singapore 138602.
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48
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Ksionda O, Limnander A, Roose JP. RasGRP Ras guanine nucleotide exchange factors in cancer. FRONTIERS IN BIOLOGY 2013; 8:508-532. [PMID: 24744772 PMCID: PMC3987922 DOI: 10.1007/s11515-013-1276-9] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
RasGRP proteins are activators of Ras and other related small GTPases by the virtue of functioning as guanine nucleotide exchange factors (GEFs). In vertebrates, four RasGRP family members have been described. RasGRP-1 through -4 share many structural domains but there are also subtle differences between each of the different family members. Whereas SOS RasGEFs are ubiquitously expressed, RasGRP proteins are expressed in distinct patterns, such as in different cells of the hematopoietic system and in the brain. Most studies have concentrated on the role of RasGRP proteins in the development and function of immune cell types because of the predominant RasGRP expression profiles in these cells and the immune phenotypes of mice deficient for Rasgrp genes. However, more recent studies demonstrate that RasGRPs also play an important role in tumorigenesis. Examples are skin- and hematological-cancers but also solid malignancies such as melanoma or prostate cancer. These novel studies bring up many new and unanswered questions related to the molecular mechanism of RasGRP-driven oncogenesis, such as new receptor systems that RasGRP appears to respond to as well as regulatory mechanism for RasGRP expression that appear to be perturbed in these cancers. Here we will review some of the known aspects of RasGRP biology in lymphocytes and will discuss the exciting new notion that RasGRP Ras exchange factors play a role in oncogenesis downstream of various growth factor receptors.
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Affiliation(s)
- Olga Ksionda
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Andre Limnander
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Jeroen P. Roose
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94143, USA
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