scholarly journals Calcium- and proton-dependent relocation of annexin A6 in Jurkat T cells stimulated for interleukin-2 secretion.

2007 ◽  
Vol 54 (2) ◽  
pp. 261-271 ◽  
Author(s):  
Paulina Podszywalow-Bartnicka ◽  
Agnieszka Strzelecka-Kiliszek ◽  
Joanna Bandorowicz-Pikula ◽  
Slawomir Pikula
Keyword(s):  
T Cells ◽  
Plasma Membrane ◽  
Secretory Granules ◽  
Intracellular Localization ◽  
Interleukin 2 ◽  
Jurkat T Cells ◽  
Vesicular Traffic ◽  
Early Endosomes ◽  
Intracellular Ca ◽  
Stimulation Of

Annexin A6 (AnxA6) is a Ca(2+)-dependent membrane-binding protein involved in vesicular traffic. The likely participation of AnxA6 in the response of lymphocytes to Ca(2+) signals has not been investigated yet. The present study focuses on intracellular relocation of AnxA6 in human Jurkat T lymphoblasts upon stimulation followed by transient increase of intracellular [Ca(2+)] and exocytosis of interleukin-2 (IL-2). Stimulation of the cells under different experimental conditions (by lowering pH and/or by rising extracellular [Ca(2+)] in the presence of ionomycin) induced time-dependent transients of intracellular [Ca(2+)] and concomitant changes in AnxA6 intracellular localization and in IL-2 secretion, with only minor effects on cell viability and apoptosis. In resting conditions (in the presence of EGTA or with no ionophore) AnxA6 was localized uniformly in the cytosol, whereas it translocated to vesicular structures beneath the plasma membrane within 5 min following stimulation of Jurkat T cells and rise of intracellular [Ca(2+)] at pH 7.4. Lowering the extracellular pH value from 7.4 to 6.0 significantly enhanced this process. AnxA6 changed its location from the cytosol to the secretory granules and early endosomes which seem to represent membranous targets for annexin. In conclusion, AnxA6 is sensitive to variations in intracellular [Ca(2+)] upon stimulation of Jurkat T cells, as manifested by a switch in its intracellular localization from the cytosol to vesicular structures located in close proximity to the plasma membrane, suggestive of participation of AnxA6 in calcium- and proton-dependent secretion of cytokines by lymphocytes.

scholarly journals Distinct intracellular localization of Lck and Fyn protein tyrosine kinases in human T lymphocytes.

1994 ◽  
Vol 125 (3) ◽  
pp. 639-649 ◽  
Author(s):  
S C Ley ◽  
M Marsh ◽  
C R Bebbington ◽  
K Proudfoot ◽  
P Jordan
Keyword(s):  
T Cells ◽  
Plasma Membrane ◽  
T Cell ◽  
T Lymphocytes ◽  
Tyrosine Kinases ◽  
Intracellular Localization ◽  
Protein Tyrosine Kinases ◽  
Jurkat T Cells ◽  
Protein Tyrosine ◽  
Mitotic Cells

Two src family kinases, lck and fyn, participate in the activation of T lymphocytes. Both of these protein tyrosine kinases are thought to function via their interaction with cell surface receptors. Thus, lck is associated with CD4, CD8, and Thy-1, whereas fyn is associated with the T cell antigen receptor and Thy-1. In this study, the intracellular localization of these two protein tyrosine kinases in T cells was analyzed by immunofluorescence and confocal microscopy. Lck was present at the plasma membrane, consistent with its proposed role in transmembrane signalling, and was also associated with pericentrosomal vesicles which co-localized with the cation-independent mannose 6-phosphate receptor. Surprisingly, fyn was not detected at the plasma membrane in either Jurkat T cells or T lymphoblasts but was closely associated with the centrosome and to microtubule bundles radiating from the centrosome. In mitotic cells, fyn co-localized with the mitotic spindle and poles. The essentially non-overlapping intracellular distributions of lck and fyn suggest that these kinases may be accessible to distinct regulatory proteins and substrates and, therefore, may regulate different aspects of T cell activation. Anti-phosphotyrosine antibody staining at the plasma membrane increases dramatically after CD3 cross-linking of Jurkat T cells. The localization of lck to the plasma membrane suggests that it may participate in mediating this increase in tyrosine phosphorylation, rather than fyn. Furthermore, the distribution of fyn in mitotic cells raises the possibility that it functions at the M phase of the cell cycle.

scholarly journals The endosomal transcriptional regulator RNF11 integrates degradation and transport of EGFR

2016 ◽  
Vol 215 (4) ◽  
pp. 543-558 ◽  
Author(s):  
Sandra Scharaw ◽  
Murat Iskar ◽  
Alessandro Ori ◽  
Gaelle Boncompain ◽  
Vibor Laketa ◽  
...  
Keyword(s):  
Endoplasmic Reticulum ◽  
Plasma Membrane ◽  
Egf Receptor ◽  
Regulatory Mechanism ◽  
Transcriptional Regulator ◽  
Transport Efficiency ◽  
Early Endosomes ◽  
Epidermal Growth ◽  
Partial Degradation ◽  
Stimulation Of

Stimulation of cells with epidermal growth factor (EGF) induces internalization and partial degradation of the EGF receptor (EGFR) by the endo-lysosomal pathway. For continuous cell functioning, EGFR plasma membrane levels are maintained by transporting newly synthesized EGFRs to the cell surface. The regulation of this process is largely unknown. In this study, we find that EGF stimulation specifically increases the transport efficiency of newly synthesized EGFRs from the endoplasmic reticulum to the plasma membrane. This coincides with an up-regulation of the inner coat protein complex II (COPII) components SEC23B, SEC24B, and SEC24D, which we show to be specifically required for EGFR transport. Up-regulation of these COPII components requires the transcriptional regulator RNF11, which localizes to early endosomes and appears additionally in the cell nucleus upon continuous EGF stimulation. Collectively, our work identifies a new regulatory mechanism that integrates the degradation and transport of EGFR in order to maintain its physiological levels at the plasma membrane.

Suppression of Synaptotagmin II restrains phorbolester-induced downregulation of protein kinase Cα by diverting the kinase from a degradative pathway to the recycling endocytic compartment

2002 ◽  
Vol 115 (15) ◽  
pp. 3083-3092 ◽  
Author(s):  
Ze Peng ◽  
Elena Grimberg ◽  
Ronit Sagi-Eisenberg
Keyword(s):  
Plasma Membrane ◽  
Protein Kinase ◽  
Phorbol Esters ◽  
Secretory Granules ◽  
Critical Factor ◽  
Cellular Level ◽  
Endocytic Compartment ◽  
Early Endosomes ◽  
Protein Kinase Cα ◽  
Rbl Cells

Downregulation of protein kinase Cα (PKCα) following long-term exposure to phorbol esters such as TPA is traffic dependent and involves delivery of the active, membrane-associated PKCα to endosomes. In this study, we show that synaptotagmin II (Syt II), a member of the Syt family of proteins, is required for TPA-induced degradation of PKCα. Thus, whereas the kinase half-life in TPA-treated cultured mast cells (the mast cell line rat basophilic leukemia RBL-2H3) is 2 hours, it is doubled in RBL-Syt II- cells, in which the cellular level of Syt II is reduced by>95% by transfection with Syt II antisense cDNA. We demonstrate that in TPA-treated RBL cells, PKCα travels from the cytosol to the plasma membrane, where it is delivered to early endosomes on its route to degradation. By contrast, in TPA-treated RBL-Syt II- cells,PKCα is diverted to recycling endosomes and remains distributed between the plasma membrane and the perinuclear recycling endocytic compartment. Notably, in both RBL and RBL-Syt II- cells, a fraction of PKCα is delivered and maintained in the secretory granules (SG). These results implicate Syt II as a critical factor for the delivery of internalized cargo for degradation. As shown here, one consequence of Syt II suppression is a delay in PKCα downregulation, resulting in its prolonged signaling.

Release and reloading of intracellular Ca stores after cholinergic stimulation of the parietal cell

1988 ◽  
Vol 254 (4) ◽  
pp. C498-C504 ◽  
Author(s):  
P. A. Negulescu ◽  
T. E. Machen
Keyword(s):  
Plasma Membrane ◽  
Parietal Cell ◽  
Base Line ◽  
Cholinergic Stimulation ◽  
Gastric Glands ◽  
Cholinergic Agonist ◽  
Intracellular Ca ◽  
Lanthanum Ion ◽  
Intact Rabbit ◽  
Stimulation Of

Microspectrofluorimetry was used to measure cytosolic free Ca, Cai, in single parietal cells of intact rabbit gastric glands loaded with the Ca-sensitive fluorescent dye, fura-2. Cells were repeatedly stimulated with the cholinergic agonist carbachol to gain insights into the membrane mechanisms involved in hormonally stimulated Ca metabolism. In either Ca-containing or Ca-free solutions, carbachol (100 microM) caused a rapid (within 30 s) elevation of Cai from a resting level of 100 nM to greater than 600 nM. After the spike, Cai decreased within 3 min to a lower level that was somewhat elevated (greater than 200 nM) over base line. This plateau was dependent on both carbachol and extracellular Ca (Cao) and could be blocked by the addition of atropine (1 microM) or lanthanum ion (La, 50 microM). The spike is due to the release of Ca from internal stores, whereas the plateau is due to Ca entry across the plasma membrane through agonist-controlled, La-inhibitable channels. After a carbachol stimulation of 3 min or longer, reloading of the internal store was absolutely dependent on Cao. Under these conditions, reloading occurred through a La-sensitive (but nifedipine- and verapamil-insensitive) pathway in the plasma membrane. No significant change in Cai was detectable during the reloading. In contrast to the longer treatments, if carbachol stimulation was terminated with atropine while Cai was still elevated, significant reloading occurred from the cytosol.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Clausmarin A, Potential Immunosuppressant Revealed by Yeast-Based Assay and Interleukin-2 Production Assay in Jurkat T Cells

PLoS ONE ◽  
2015 ◽  
Vol 10 (8) ◽  
pp. e0136804 ◽  
Author(s):  
Pitipreya Suauam ◽  
Boon-ek Yingyongnarongkul ◽  
Tanapat Palaga ◽  
Tokichi Miyakawa ◽  
Chulee Yompakdee
Keyword(s):  
T Cells ◽  
Interleukin 2 ◽  
Jurkat T Cells

Manganese promotes phorbol ester-induced interleukin-2 production via AP-1 activation in Jurkat T-cells

2012 ◽  
Vol 211 (3) ◽  
pp. 312-318 ◽  
Author(s):  
Susumu Tanaka ◽  
Yasunori Masuda ◽  
Chihiro Honma ◽  
Kohei Hosaka ◽  
Katsunori Takahashi ◽  
...  
Keyword(s):  
T Cells ◽  
Phorbol Ester ◽  
Interleukin 2 ◽  
Jurkat T Cells

scholarly journals Stimulation of CD28 triggers an association between CD28 and phosphatidylinositol 3-kinase in Jurkat T cells.

1994 ◽  
Vol 179 (3) ◽  
pp. 1071-1076 ◽  
Author(s):  
K E Truitt ◽  
C M Hicks ◽  
J B Imboden
Keyword(s):  
T Cells ◽  
Growth Factor Receptor ◽  
Jurkat Cells ◽  
Phosphatidylinositol 3 Kinase ◽  
Jurkat T Cells ◽  
Cell Surface Molecule ◽  
Natural Ligand ◽  
High Affinity Binding Site ◽  
Stimulation Of ◽  
Phosphatidylinositol 3

The T cell surface molecule CD28 can provide costimulatory signals that permit the full activation of T cells. Here we demonstrate that stimulation of CD28, either by B7, its natural ligand, or by the anti-CD28 monoclonal antibody 9.3, induces an association between CD28 and phosphatidylinositol 3-kinase (PI3-K) in Jurkat T cells, raising the possibility that an interaction with PI3-K contributes to CD28-mediated signaling. To examine the mechanism of the association, we synthesized tyrosine-phosphorylated oligopeptides corresponding to each of the four tyrosines in the CD28 cytoplasmic domain. When added to lysates of B7-stimulated Jurkat cells, the oligopeptide corresponding to Tyr 173 inhibits the coimmunoprecipitation of PI3-K with CD28; the other oligopeptides have no effect. Tyr 173 is contained within the sequence YMNM, a motif that is also found in the platelet-derived growth factor receptor and that, when phosphorylated, forms a high affinity binding site for the p85 subunit of PI3-K. These observations suggest that phosphorylation of Tyr 173 may mediate the interaction between CD28 and PI3-K. However, because CD28 is not known to be phosphorylated, it remains possible that CD28 interacts with PI3-K through a mechanism independent of tyrosine phosphorylation.

scholarly journals Stimulation of T cells through the CD3/T-cell receptor complex: role of cytoplasmic calcium, protein kinase C translocation, and phosphorylation of pp60c-src in the activation pathway.

1987 ◽  
Vol 7 (2) ◽  
pp. 650-656 ◽  
Author(s):  
J A Ledbetter ◽  
L E Gentry ◽  
C H June ◽  
P S Rabinovitch ◽  
A F Purchio
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Receptor ◽  
Solid Phase ◽  
Interleukin 2 ◽  
Cell Receptor ◽  
Jurkat Cells ◽  
Receptor Complex ◽  
Kinase C ◽  
Stimulation Of

Stimulation of T cells or the Jurkat T-cell line with soluble antibodies to the CD3/T-cell receptor complex causes mobilization of cytoplasmic Ca2+, which is blocked by pertussis toxin but not by ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid, and translocation of protein kinase C activity from the cytoplasm to the membrane. Such stimulation also causes phosphorylation of pp60c-src at an amino-terminal serine residue. These activities are consistent with induction of phosphatidylinositol metabolism after antibody binding. Anti-CD3 stimulation with antibody in solution, however, does not cause Jurkat cells to release interleukin 2 and blocks rather than induces proliferation of T cells. Induction of interleukin 2 production by Jurkat cells and proliferation by normal T cells requires anti-CD3 stimulation with antibody on a solid support, such as Sepharose beads or a plastic dish. Thus, we examined phosphorylation of pp60c-src after stimulation of Jurkat cells with anti-CD3 in solution or on solid phase. Both of these caused serine phosphorylation of pp60c-src that was indistinguishable even after 4 h of stimulation. These results indicate that the mode of anti-CD3 stimulation (in solution or on solid phase) controls a cellular function that modifies the consequences of signal transduction through phosphatidylinositol turnover.

scholarly journals Interleukin-2 induces tyrosine phosphorylation of the vav proto-oncogene product in human T cells: lack of requirement for the tyrosine kinase lck

1993 ◽  
Vol 294 (2) ◽  
pp. 339-342 ◽  
Author(s):  
G A Evans ◽  
O M Z Howard ◽  
R Erwin ◽  
W L Farrar
Keyword(s):  
Signal Transduction ◽  
T Cells ◽  
Tyrosine Kinase ◽  
Cell Line ◽  
Tyrosine Phosphorylation ◽  
Interleukin 2 ◽  
Maximum Increase ◽  
Human T Cell ◽  
Human T Cells ◽  
Stimulation Of

The haematopoietic protein, p95vav, has been shown to be a tyrosine kinase substrate and to have tyrosine kinase-modulated guanine-nucleotide-releasing-factor activity. This implies a function in the control of ras or ras-like proteins. Because ras activation has been shown to be a downstream event following stimulation of the interleukin-2 (IL-2) receptor, we investigated the possibility that vav was involved in IL-2 signal transduction pathways, using human T cells as a model. We found rapid tyrosine phosphorylation of vav in response to IL-2 within 1 min, with maximum increase of phosphorylation of 5-fold occurring by 5 min after treatment in normal human T cells. IL-2 stimulation of the human T-cell line YT and a subclone of the YT cell line (YTlck-) that does not express message for the src-family kinase p56lck also results in a rapid rate of tyrosine phosphorylation of vav of more than 5-fold by 5 min. These results suggest that vav may play an important role in IL-2-stimulated signal transduction and that there is not a strict requirement for the tyrosine kinase p56lck.

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