scholarly journals T cell receptor for antigen induces linker for activation of T cell–dependent activation of a negative signaling complex involving Dok-2, SHIP-1, and Grb-2

2006 ◽  
Vol 203 (11) ◽  
pp. 2509-2518 ◽  
Author(s):  
Shen Dong ◽  
Béatrice Corre ◽  
Eliane Foulon ◽  
Evelyne Dufour ◽  
André Veillette ◽  
...  
Keyword(s):  
T Cell ◽  
T Cell Receptor ◽  
Critical Role ◽  
Adaptor Proteins ◽  
Cell Receptor ◽  
Negative Control ◽  
Inositol Polyphosphate ◽  
Tcr Signaling ◽  
Signaling Complex ◽  
Src Homology 2 Domain

Adaptor proteins positively or negatively regulate the T cell receptor for antigen (TCR) signaling cascade. We report that after TCR stimulation, the inhibitory adaptor downstream of kinase (Dok)-2 and its homologue Dok-1 are involved in a multimolecular complex including the lipid phosphatase Src homology 2 domain–containing inositol polyphosphate 5′-phosphatase (SHIP)-1 and Grb-2 which interacts with the membrane signaling scaffold linker for activation of T cells (LAT). Knockdown of LAT and SHIP-1 expression indicated that SHIP-1 favored recruitment of Dok-2 to LAT. Knockdown of Dok-2 and Dok-1 revealed their negative control on Akt and, unexpectedly, on Zap-70 activation. Our findings support the view that Dok-1 and -2 are critical elements of a LAT-dependent negative feedback loop that attenuates early TCR signal. Dok-1 and -2 may therefore exert a critical role in shaping the immune response and as gatekeepers for T cell tolerance.

scholarly journals Qualitative and quantitative contributions of the T cell receptor zeta chain to mature T cell apoptosis.

1996 ◽  
Vol 183 (5) ◽  
pp. 2109-2117 ◽  
Author(s):  
B Combadière ◽  
M Freedman ◽  
L Chen ◽  
E W Shores ◽  
P Love ◽  
...  
Keyword(s):  
T Cell ◽  
T Cell Receptor ◽  
Cell Apoptosis ◽  
Cell Receptor ◽  
Single Chain ◽  
Tcr Signaling ◽  
T Cell Apoptosis ◽  
Zeta Chain ◽  
Src Homology ◽  
Src Homology 2 Domain

Engagement of the T cell receptor (TCR) of mature T lymphocytes can lead either to activation/proliferation responses or programmed cell death. To understand the molecular regulation of these two fundamentally different outcomes of TCR signaling, we investigated the participation of various components of the TCR-CD3 complex. We found that the TCR-zeta chain, while not absolutely required, was especially effective at promoting mature T cell apoptosis compared with the CD3 epsilon, gamma, or delta chains. We also carried out mutagenesis to address the role of the immunoreceptor tyrosine-based activation motifs (ITAMs) that are the principal signaling components found three times in the TCR-zeta chain and once in each of the CD3 epsilon, gamma, or delta chains. We found that the ability of the TCR-zeta chain to promote apoptosis results both from a quantitative effect of the presence of multiple ITAMs as well as qualitatively different contributions made by individual ITAMs. Apoptosis induced by single chain chimeras revealed that the first zeta ITAM stimulated greater apoptosis than the third zeta ITAM, and the second zeta ITAM was unable to trigger apoptosis. Because microheterogeneity in the amino acid sequence of the various ITAM motifs found in the TCR-zeta and CD3 chains predicts interactions with distinct src-homology-2-domain signaling proteins, our results suggest the possibility that individual ITAM motifs might play unique roles in TCR responses by engaging specific signaling pathways.

scholarly journals Usp12 stabilizes the T-cell receptor complex at the cell surface during signaling

2016 ◽  
Vol 113 (6) ◽  
pp. E705-E714 ◽  
Author(s):  
Akhee S. Jahan ◽  
Maxime Lestra ◽  
Lee Kim Swee ◽  
Ying Fan ◽  
Mart M. Lamers ◽  
...  
Keyword(s):  
T Cell ◽  
T Cell Receptor ◽  
Posttranslational Modifications ◽  
Protein Function ◽  
Adaptor Proteins ◽  
Cell Receptor ◽  
Surface Expression ◽  
Jurkat Cells ◽  
Tcr Signaling ◽  
Primary Mouse

Posttranslational modifications are central to the spatial and temporal regulation of protein function. Among others, phosphorylation and ubiquitylation are known to regulate proximal T-cell receptor (TCR) signaling. Here we used a systematic and unbiased approach to uncover deubiquitylating enzymes (DUBs) that participate during TCR signaling in primary mouse T lymphocytes. Using a C-terminally modified vinyl methyl ester variant of ubiquitin (HA-Ub-VME), we captured DUBs that are differentially recruited to the cytosol on TCR activation. We identified ubiquitin-specific peptidase (Usp) 12 and Usp46, which had not been previously described in this pathway. Stimulation with anti-CD3 resulted in phosphorylation and time-dependent translocation of Usp12 from the nucleus to the cytosol. Usp12−/− Jurkat cells displayed defective NFκB, NFAT, and MAPK activities owing to attenuated surface expression of TCR, which were rescued on reconstitution of wild type Usp12. Proximity-based labeling with BirA-Usp12 revealed several TCR adaptor proteins acting as interactors in stimulated cells, of which LAT and Trat1 displayed reduced expression in Usp12−/− cells. We demonstrate that Usp12 deubiquitylates and prevents lysosomal degradation of LAT and Trat1 to maintain the proximal TCR complex for the duration of signaling. Our approach benefits from the use of activity-based probes in primary cells without any previous genome modification, and underscores the importance of ubiquitin-mediated regulation to refine signaling cascades.

Inhibition of T cell activation and function by the adaptor protein CIN85

2019 ◽  
Vol 12 (567) ◽  
pp. eaav4373 ◽  
Author(s):  
Mei Suen Kong ◽  
Akiko Hashimoto-Tane ◽  
Yusuke Kawashima ◽  
Machie Sakuma ◽  
Tadashi Yokosuka ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Activation ◽  
Cell Activation ◽  
Adaptor Protein ◽  
Adaptor Proteins ◽  
Cell Receptor ◽  
Sh2 Domain ◽  
Tcr Signaling ◽  
Signaling Complex

T cell activation is initiated by signaling molecules downstream of the T cell receptor (TCR) that are organized by adaptor proteins. CIN85 (Cbl-interacting protein of 85 kDa) is one such adaptor protein. Here, we showed that CIN85 limited T cell responses to TCR stimulation. Compared to activated wild-type (WT) T cells, those that lacked CIN85 produced more IL-2 and exhibited greater proliferation. After stimulation of WT T cells with their cognate antigen, CIN85 was recruited to the TCR signaling complex. Early TCR signaling events, such as phosphorylation of ζ-chain–associated protein kinase 70 (Zap70), Src homology 2 (SH2) domain–containing leukocyte protein of 76 kDa (SLP76), and extracellular signal–regulated kinase (Erk), were enhanced in CIN85-deficient T cells. The inhibitory function of CIN85 required the SH3 and PR regions of the adaptor, which associated with the phosphatase suppressor of TCR signaling–2 (Sts-2) after TCR stimulation. Together, our data suggest that CIN85 is recruited to the TCR signaling complex and mediates inhibition of T cell activation through its association with Sts-2.

scholarly journals SKAP55 Coupled with CD45 Positively Regulates T-Cell Receptor-Mediated Gene Transcription

2002 ◽  
Vol 22 (8) ◽  
pp. 2673-2686 ◽  
Author(s):  
Liangtang Wu ◽  
Jun Fu ◽  
Shi-Hsiang Shen
Keyword(s):  
T Cell ◽  
T Cell Receptor ◽  
Transcriptional Activation ◽  
Mutational Analysis ◽  
Critical Role ◽  
Cell Receptor ◽  
Jurkat Cells ◽  
Tcr Signaling

ABSTRACT CD45 plays a critical role in T-cell receptor (TCR)-mediated signaling. In a yeast two-hybrid screen, SKAP55, the Src kinase-associated phosphoprotein of unknown function, was found as a substrate which associated with CD45 in vivo. Mutational analysis demonstrated the pivotal role of Tyr-232 in SKAP55 in the association with CD45. In Jurkat cells, anti-CD3 antibody stimulation promoted SKAP55 tyrosine phosphorylation and translocation from the cytoplasm to the membrane. Overexpression of SKAP55 in these cells induced transcriptional activation of the IL-2 promoter, while mutant SKAP55-Y232F totally suppressed the promoter activity. Furthermore, overexpression of SKAP55-Y232F also caused the tyrosine hyperphosphorylation of Fyn with a decreased kinase activity. Thus, SKAP55 is an essential adapter to couple CD45 with the Src family kinases for dephosphorylation and, thus, positively regulates TCR signaling.

scholarly journals T cell receptor (TCR) signaling in health and disease

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Kinjal Shah ◽  
Amr Al-Haidari ◽  
Jianmin Sun ◽  
Julhash U. Kazi
Keyword(s):  
Signal Transduction ◽  
T Cells ◽  
T Cell ◽  
T Cell Receptor ◽  
Protein Interactions ◽  
Adaptor Proteins ◽  
Cell Receptor ◽  
Signal Transduction Pathways ◽  
Protein Protein Interactions ◽  
Tcr Signaling

AbstractInteraction of the T cell receptor (TCR) with an MHC-antigenic peptide complex results in changes at the molecular and cellular levels in T cells. The outside environmental cues are translated into various signal transduction pathways within the cell, which mediate the activation of various genes with the help of specific transcription factors. These signaling networks propagate with the help of various effector enzymes, such as kinases, phosphatases, and phospholipases. Integration of these disparate signal transduction pathways is done with the help of adaptor proteins that are non-enzymatic in function and that serve as a scaffold for various protein–protein interactions. This process aids in connecting the proximal to distal signaling pathways, thereby contributing to the full activation of T cells. This review provides a comprehensive snapshot of the various molecules involved in regulating T cell receptor signaling, covering both enzymes and adaptors, and will discuss their role in human disease.

scholarly journals Loss of tonic T-cell receptor signals alters the generation but not the persistence of CD8+ memory T cells

Blood ◽  
2010 ◽  
Vol 116 (25) ◽  
pp. 5560-5570 ◽  
Author(s):  
Karla R. Wiehagen ◽  
Evann Corbo ◽  
Michelle Schmidt ◽  
Haina Shin ◽  
E. John Wherry ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Receptor ◽  
Cell Receptor ◽  
Lymphocytic Choriomeningitis ◽  
Sh2 Domain ◽  
Normal Numbers ◽  
Tcr Signaling ◽  
Tcr Signals

Abstract The requirements for tonic T-cell receptor (TCR) signaling in CD8+ memory T-cell generation and homeostasis are poorly defined. The SRC homology 2 (SH2)-domain–containing leukocyte protein of 76 kDa (SLP-76) is critical for proximal TCR-generated signaling. We used temporally mediated deletion of SLP-76 to interrupt tonic and activating TCR signals after clearance of the lymphocytic choriomeningitis virus (LCMV). SLP-76–dependent signals are required during the contraction phase of the immune response for the normal generation of CD8 memory precursor cells. Conversely, LCMV-specific memory CD8 T cells generated in the presence of SLP-76 and then acutely deprived of TCR-mediated signals persist in vivo in normal numbers for more than 40 weeks. Tonic TCR signals are not required for the transition of the memory pool toward a central memory phenotype, but the absence of SLP-76 during memory homeostasis substantially alters the kinetics. Our data are consistent with a model in which tonic TCR signals are required at multiple stages of differentiation, but are dispensable for memory CD8 T-cell persistence.

scholarly journals Fyn-Binding Protein (Fyb)/Slp-76–Associated Protein (Slap), Ena/Vasodilator-Stimulated Phosphoprotein (Vasp) Proteins and the Arp2/3 Complex Link T Cell Receptor (Tcr) Signaling to the Actin Cytoskeleton

2000 ◽  
Vol 149 (1) ◽  
pp. 181-194 ◽  
Author(s):  
Matthias Krause ◽  
Antonio S. Sechi ◽  
Marlies Konradt ◽  
David Monner ◽  
Frank B. Gertler ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Actin Cytoskeleton ◽  
T Cell Receptor ◽  
Cell Receptor ◽  
T Cell Signaling ◽  
Tcr Signaling ◽  
Activated T Cells ◽  
Antigen Presenting ◽  
Syndrome Protein

T cell receptor (TCR)-driven activation of helper T cells induces a rapid polarization of their cytoskeleton towards bound antigen presenting cells (APCs). We have identified the Fyn- and SLP-76–associated protein Fyb/SLAP as a new ligand for Ena/ vasodilator-stimulated phosphoprotein (VASP) homology 1 (EVH1) domains. Upon TCR engagement, Fyb/SLAP localizes at the interface between T cells and anti-CD3–coated beads, where Evl, a member of the Ena/VASP family, Wiskott-Aldrich syndrome protein (WASP) and the Arp2/3 complex are also found. In addition, Fyb/SLAP is restricted to lamellipodia of spreading platelets. In activated T cells, Fyb/SLAP associates with Ena/VASP family proteins and is present within biochemical complexes containing WASP, Nck, and SLP-76. Inhibition of binding between Fyb/SLAP and Ena/VASP proteins or WASP and the Arp2/3 complex impairs TCR-dependent actin rearrangement, suggesting that these interactions play a key role in linking T cell signaling to remodeling of the actin cytoskeleton.

scholarly journals Leukocyte-associated immunoglobulin-like receptor 1 inhibits T-cell signaling by decreasing protein phosphorylation in the T-cell signaling pathway

2020 ◽  
Vol 295 (8) ◽  
pp. 2239-2247 ◽  
Author(s):  
Jeoung-Eun Park ◽  
David D. Brand ◽  
Edward F. Rosloniec ◽  
Ae-Kyung Yi ◽  
John M. Stuart ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Tyrosine Kinase ◽  
Cell Signaling ◽  
Signaling Pathway ◽  
T Cell Receptor ◽  
Cell Receptor ◽  
T Cell Signaling ◽  
Tcr Signaling ◽  
Cell Signaling Pathway

Multiple observations implicate T-cell dysregulation as a central event in the pathogenesis of rheumatoid arthritis. Here, we investigated mechanisms for suppressing T-cell activation via the inhibitory receptor leukocyte-associated immunoglobulin-like receptor 1 (LAIR-1). To determine how LAIR-1 affects T-cell receptor (TCR) signaling, we compared 1) T cells from LAIR-1–sufficient and –deficient mice, 2) Jurkat cells expressing either LAIR-1 mutants or C-terminal Src kinase (CSK) mutants, and 3) T cells from mice that contain a CSK transgene susceptible to chemical inhibition. Our results indicated that LAIR-1 engagement by collagen or by complement C1q (C1Q, which contains a collagen-like domain) inhibits TCR signaling by decreasing the phosphorylation of key components in the canonical T-cell signaling pathway, including LCK proto-oncogene SRC family tyrosine kinase (LCK), LYN proto-oncogene SRC family tyrosine kinase (LYN), ζ chain of T-cell receptor–associated protein kinase 70 (ZAP-70), and three mitogen-activated protein kinases (extracellular signal–regulated kinase, c-Jun N-terminal kinase 1/2, and p38). The intracellular region of LAIR-1 contains two immunoreceptor tyrosine-based inhibition motifs that are both phosphorylated by LAIR-1 activation, and immunoprecipitation experiments revealed that Tyr-251 in LAIR-1 binds CSK. Using CRISPR/Cas9-mediated genome editing, we demonstrate that CSK is essential for the LAIR-1–induced inhibition of the human TCR signal transduction. T cells from mice that expressed a PP1 analog–sensitive form of CSK (CskAS) corroborated these findings, and we also found that Tyr-251 is critical for LAIR-1's inhibitory function. We propose that LAIR-1 activation may be a strategy for controlling inflammation and may offer a potential therapeutic approach for managing autoimmune diseases.

scholarly journals A role for interleukin 4 in the differentiation of mature T cell receptor gamma/delta + cells from human intrathymic T cell precursors.

1990 ◽  
Vol 172 (2) ◽  
pp. 439-446 ◽  
Author(s):  
A Bárcena ◽  
M L Toribio ◽  
L Pezzi ◽  
C Martínez
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Receptor ◽  
Critical Role ◽  
Cell Receptor ◽  
Interleukin 4 ◽  
Gamma Delta ◽  
Consistent Finding ◽  
Delta Cells ◽  
Gamma Delta Cells

We have analyzed the effect of human recombinant interleukin 4 (rIL-4) on the growth and differentiation of human intrathymic pre-T cells (CD7+2+1-3-4-8-). We describe that this population of T cell precursors proliferates in response to rIL-4 (in the absence of mitogens or other stimulatory signals) in a dose-dependent way. The IL-4-induced proliferation is independent of the IL-2 pathway, as it cannot be inhibited with an anti-IL-2 receptor alpha chain antibody. In our culture conditions, rIL-4 also promotes the differentiation of pre-T cells into phenotypically mature T cells. Although both CD3/T cell receptor (TCR)-alpha/beta + and CD3-gamma/delta + T cells were obtained, the preferential differentiation into TCR-gamma/delta + cells was a consistent finding. These results suggest that, in addition to IL-2, IL-4 plays a critical role in promoting growth and differentiation of intrathymic T cell precursors at early stages of T cell development.

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