scholarly journals Calcium Regulation of GM-CSF by Calmodulin-Dependent Kinase II Phosphorylation of Ets1

2002 ◽  
Vol 13 (12) ◽  
pp. 4497-4507 ◽  
Author(s):  
Hebin Liu ◽  
Thomas Grundström
Keyword(s):  
Transcription Factor ◽  
T Cell ◽  
T Cell Receptor ◽  
Inflammatory Responses ◽  
Cell Types ◽  
Cell Receptor ◽  
Receptor Activation ◽  
Wild Type ◽  
Gm Csf

The multipotent cytokine granulocyte macrophage-colony stimulating factor (GM-CSF) is involved in particular in the physiological response to infection and in inflammatory responses. GM-CSF is produced by many cell types, including T lymphocytes responding to T-cell receptor activation and mantle zone B lymphocytes. B-cell receptor and T-cell receptor activation generates two major signals: an increase in intracellular Ca2+concentration and a protein kinase cascade. Previous studies have shown that the Ca2+/calmodulin-dependent phosphatase calcineurin mediates stimulation of GM-CSF transcription in response to Ca2+. In this study, we show that Ca2+signaling also regulates GM-CSF transcription negatively through Ca2+/calmodulin-dependent kinase II (CaMK II) phosphorylation of serines in the autoinhibitory domain for DNA binding of the transcription factor Ets1. Wild-type Ets1 negatively affects GM-CSF transcription on Ca2+stimulation in the presence of cyclosporin A, which inhibits calcineurin. Conversely, Ets1 with mutated CaMK II target serines showed an increase in transactivation of the GM-CSF promoter/enhancer. Moreover, constitutively active CaMK II inhibited transactivation of GM-CSF by wild-type Ets1 but not by Ets1 with mutated CaMK II sites. Mutation of CaMK II target serines in Ets1 also relieves inhibition of cooperative transactivation of GM-CSF with the Runx1/AML1 transcription factor. In addition, the Ca2+-dependent phosphorylation of Ets1 reduces the binding of Ets1 to the GM-CSF promoter in vivo.

scholarly journals T-cell calcium dynamics visualized in a ratiometric tdTomato-GCaMP6f transgenic reporter mouse

eLife ◽  
2017 ◽  
Vol 6 ◽  
Author(s):  
Tobias X Dong ◽  
Shivashankar Othy ◽  
Amit Jairaman ◽  
Jonathan Skupsky ◽  
Angel Zavala ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Tracking ◽  
Cell Types ◽  
Cell Receptor ◽  
Receptor Activation ◽  
Specific Cell ◽  
Transgenic Expression ◽  
Reporter Mouse

Calcium is an essential cellular messenger that regulates numerous functions in living organisms. Here, we describe development and characterization of ‘Salsa6f’, a fusion of GCaMP6f and tdTomato optimized for cell tracking while monitoring cytosolic Ca2+, and a transgenic Ca2+ reporter mouse with Salsa6f targeted to the Rosa26 locus for Cre-dependent expression in specific cell types. The development and function of T cells was unaffected in Cd4-Salsa6f mice. We describe Ca2+ signals reported by Salsa6f during T cell receptor activation in naive T cells, helper Th17 T cells and regulatory T cells, and Ca2+ signals mediated in T cells by an activator of mechanosensitive Piezo1 channels. Transgenic expression of Salsa6f enables ratiometric imaging of Ca2+ signals in complex tissue environments found in vivo. Two-photon imaging of migrating T cells in the steady-state lymph node revealed both cell-wide and localized sub-cellular Ca2+ transients (‘sparkles’) as cells migrate.

scholarly journals Phosphorylation of a Tyrosine Residue on Zap70 by Lck and Its Subsequent Binding via an SH2 Domain May Be a Key Gatekeeper of T Cell Receptor SignalingIn Vivo

2016 ◽  
Vol 36 (18) ◽  
pp. 2396-2402 ◽  
Author(s):  
Peter A. Thill ◽  
Arthur Weiss ◽  
Arup K. Chakraborty
Keyword(s):  
T Cell ◽  
T Cell Receptor ◽  
Cell Receptor ◽  
Receptor Activation ◽  
Sh2 Domain ◽  
Tcr Signaling ◽  
New Model ◽  
Downstream Signaling ◽  
Conventional Models

The initiation of signaling in T lymphocytes in response to the binding of the T cell receptor (TCR) to cognate ligands is a key step in the emergence of adaptive immune responses. Conventional models posit that TCR signaling is initiated by the phosphorylation of receptor-associated immune receptor activation motifs (ITAMs). The cytoplasmic tyrosine kinase Zap70 binds to phosphorylated ITAMs, is subsequently activated, and then propagates downstream signaling. While evidence for such models is provided by experiments with cell lines,in vivo, Zap70 is bound to phosphorylated ITAMs in resting T cells. However, Zap70 is activated only upon TCR binding to cognate ligand. We report the results of computational studies of a new model for the initiation of TCR signaling that incorporates thesein vivoobservations. Importantly, the new model is shown to allow better and faster TCR discrimination between self-ligands and foreign ligands. The new model is consistent with many past experimental observations, and experiments that could further test the model are proposed.

Biased T-cell receptor delta element recombination in scid thymocytes

1993 ◽  
Vol 13 (6) ◽  
pp. 3632-3640
Author(s):  
A M Carroll ◽  
J K Slack ◽  
W T Chang
Keyword(s):  
T Cell ◽  
T Cell Receptor ◽  
Severe Combined Immunodeficiency ◽  
Cell Receptor ◽  
Lymphocyte Development ◽  
Gene Rearrangements ◽  
Combined Immunodeficiency ◽  
Full Understanding ◽  
Wild Type

Thymocytes in mutant mice with severe combined immunodeficiency (scid thymocytes) show ongoing recombination of some T-cell receptor delta gene elements, generating signal joints quantitatively and qualitatively indistinguishable from those in wild-type fetal thymocytes. Excised D delta 2-J delta 1 and D delta 1-D delta 2 rearrangements are detectable at levels equivalent to or greater than those in thymocytes from wild-type mice on fetal day 15. Signal junctional modification, shown here to occur frequently in wild-type adult but not newborn excised D delta 2-J delta 1 junctions, can occur normally in adult scid thymocytes. Excised D delta 1-D delta 2 scid junctions, similar to wild-type thymocytes, include pseudonormal coding junctions as well as signal junctions. Inversional D delta 1-D delta 2 rearrangements, generating conventional hybrid junctions, are also reproducibly detectable in scid thymus DNA. These hybrids, unlike those reported for artificial recombination constructs, do not show extensive nucleotide loss. In contrast to the normal or high incidences of D delta 1-, D delta 2-, and J delta 1-associated signal junctions in scid thymocytes, V delta 1, V gamma 3, and V gamma 1.2 signal products are undetectable in scid thymocytes or are detectable at levels at least 10-fold lower than the levels in wild-type fetal thymocytes. These findings confirm biased T-cell receptor element recombination by V(D)J recombinase activity of nontransformed scid thymocytes and indicate that analysis of in vivo-mediated gene rearrangements is important for full understanding of how the scid mutation arrests lymphocyte development.

scholarly journals Biased T-cell receptor delta element recombination in scid thymocytes.

1993 ◽  
Vol 13 (6) ◽  
pp. 3632-3640 ◽  
Author(s):  
A M Carroll ◽  
J K Slack ◽  
W T Chang
Keyword(s):  
T Cell ◽  
T Cell Receptor ◽  
Severe Combined Immunodeficiency ◽  
Cell Receptor ◽  
Lymphocyte Development ◽  
Gene Rearrangements ◽  
Combined Immunodeficiency ◽  
Full Understanding ◽  
Wild Type

Thymocytes in mutant mice with severe combined immunodeficiency (scid thymocytes) show ongoing recombination of some T-cell receptor delta gene elements, generating signal joints quantitatively and qualitatively indistinguishable from those in wild-type fetal thymocytes. Excised D delta 2-J delta 1 and D delta 1-D delta 2 rearrangements are detectable at levels equivalent to or greater than those in thymocytes from wild-type mice on fetal day 15. Signal junctional modification, shown here to occur frequently in wild-type adult but not newborn excised D delta 2-J delta 1 junctions, can occur normally in adult scid thymocytes. Excised D delta 1-D delta 2 scid junctions, similar to wild-type thymocytes, include pseudonormal coding junctions as well as signal junctions. Inversional D delta 1-D delta 2 rearrangements, generating conventional hybrid junctions, are also reproducibly detectable in scid thymus DNA. These hybrids, unlike those reported for artificial recombination constructs, do not show extensive nucleotide loss. In contrast to the normal or high incidences of D delta 1-, D delta 2-, and J delta 1-associated signal junctions in scid thymocytes, V delta 1, V gamma 3, and V gamma 1.2 signal products are undetectable in scid thymocytes or are detectable at levels at least 10-fold lower than the levels in wild-type fetal thymocytes. These findings confirm biased T-cell receptor element recombination by V(D)J recombinase activity of nontransformed scid thymocytes and indicate that analysis of in vivo-mediated gene rearrangements is important for full understanding of how the scid mutation arrests lymphocyte development.

scholarly journals Regulation of  T Cell Receptor δ Gene Rearrangement by CBF/PEBP2

1997 ◽  
Vol 185 (7) ◽  
pp. 1193-1202 ◽  
Author(s):  
Pilar Lauzurica ◽  
Xiao-Ping Zhong ◽  
Michael S. Krangel ◽  
Joseph L. Roberts
Keyword(s):  
Transcription Factor ◽  
T Cell ◽  
Binding Site ◽  
T Cell Receptor ◽  
Cell Receptor ◽  
Vdj Recombination ◽  
Human T Cell ◽  
Transgenic Lines ◽  
Factor C

We have analyzed transgenic mice carrying versions of a human T cell receptor (TCR)-δ gene minilocus to study the developmental control of  VDJ (variable/diversity/joining) recombination. Previous data indicated that a 1.4-kb DNA fragment carrying the TCR-δ enhancer (Eδ) efficiently activates minilocus VDJ recombination in vivo. We tested whether the transcription factor CBF/PEBP2 plays an important role in the ability of Eδ to activate VDJ recombination by analyzing VDJ recombination in mice carrying a minilocus in which the δE3 element of Eδ includes a mutated CBF/PEBP2 binding site. The enhancer-dependent VD to J step of minilocus rearrangement was dramatically inhibited in three of four transgenic lines, arguing that the binding of CBF/PEBP2 plays a role in modulating local accessibility to the VDJ recombinase in vivo. Because mutation of the δE3 binding site for the transcription factor c-Myb had previously established a similar role for c-Myb, and because a 60-bp fragment of Eδ carrying δE3 and δE4 binding sites for CBF/PEBP2, c-Myb, and GATA-3 displays significant enhancer activity in transient transfection experiments, we tested whether this fragment of Eδ is sufficient to activate VDJ recombination in vivo. This fragment failed to efficiently activate the enhancerdependent VD to J step of minilocus rearrangement in all three transgenic lines examined, indicating that the binding of CBF/PEBP2 and c-Myb to their cognate sites within Eδ, although necessary, is not sufficient for the activation of VDJ recombination by Eδ. These results imply that CBF/PEBP2 and c-Myb collaborate with additional factors that bind elsewhere within Eδ to modulate local accessibility to the VDJ recombinase in vivo.

scholarly journals Disruption of Mekk2 in Mice Reveals an Unexpected Role for MEKK2 in Modulating T-Cell Receptor Signal Transduction

2002 ◽  
Vol 22 (16) ◽  
pp. 5761-5768 ◽  
Author(s):  
Zijian Guo ◽  
Gavin Clydesdale ◽  
Jinke Cheng ◽  
Kihwan Kim ◽  
Lin Gan ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Receptor ◽  
Interleukin 2 ◽  
Cell Receptor ◽  
Mapk Signaling ◽  
Mitogen Activated Protein Kinase ◽  
Wild Type ◽  
Kinase Gene

ABSTRACT MEKK2 is a member of the mitogen-activated protein kinase (MAPK) kinase kinase gene family involved in regulating multiple MAPK signaling pathways. To elucidate the in vivo function of MEKK2, we generated mice carrying a targeted mutation in the Mekk2 locus. Mekk2 −/− mice are viable and fertile. Major subsets of thymic and spleen T cells in Mekk2-deficient mice were indistinguishable from those in wild-type mice. B-cell development appeared to proceed similarly in the bone marrow of Mekk2-deficient and wild-type mice. However, Mekk2 −/− T-cell proliferation was augmented in response to anti-CD3 monoclonal antibody (MAb) stimulation, and these T cells produced more interleukin 2 and gamma interferon than did the wild-type T cells, suggesting that MEKK2 may be involved in controlling the strength of T-cell receptor (TCR) signaling. Consistently, Mekk2 −/− thymocytes were more susceptible than wild-type thymocytes to anti-CD3 MAb-induced cell death. Furthermore, TCR-mediated c-Jun N-terminal kinase activation was not blocked but moderately enhanced in Mekk2 −/− T cells. Neither extracellular signal-regulated kinase nor p38 MAPK activation was affected in Mekk2 −/− T cells. In conclusion, we found that MEKK2 may be required for controlling the strength of TCR/CD3 signaling.

scholarly journals Fusion transcripts FYN-TRAF3IP2 and KHDRBS1-LCK hijack T cell receptor signaling in peripheral T-cell lymphoma, not otherwise specified

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Koen Debackere ◽  
Lukas Marcelis ◽  
Sofie Demeyer ◽  
Marlies Vanden Bempt ◽  
Nicole Mentens ◽  
...  
Keyword(s):  
T Cell ◽  
T Cell Receptor ◽  
Cell Lymphoma ◽  
Ex Vivo ◽  
Cell Receptor ◽  
T Cell Lymphoma ◽  
Peripheral T Cell Lymphoma ◽  
Fusion Transcripts ◽  
Not Otherwise Specified

AbstractPeripheral T-cell lymphoma (PTCL) is a heterogeneous group of non-Hodgkin lymphomas with poor prognosis. Up to 30% of PTCL lack distinctive features and are classified as PTCL, not otherwise specified (PTCL-NOS). To further improve our understanding of the genetic landscape and biology of PTCL-NOS, we perform RNA-sequencing of 18 cases and validate results in an independent cohort of 37 PTCL cases. We identify FYN-TRAF3IP2, KHDRBS1-LCK and SIN3A-FOXO1 as new in-frame fusion transcripts, with FYN-TRAF3IP2 as a recurrent fusion detected in 8 of 55 cases. Using ex vivo and in vivo experiments, we demonstrate that FYN-TRAF3IP2 and KHDRBS1-LCK activate signaling pathways downstream of the T cell receptor (TCR) complex and confer therapeutic vulnerability to clinically available drugs.

Sign in / Sign up

Export Citation Format

Share Document