The role of SHIP1 in T-lymphocyte life and death

in Biochemical Society Transactions (2007), 35(Pt 2), 277-280

SHIP1 [SH2 (Src homology 2)-containing inositol phosphatase-1], an inositol 5-phosphatase expressed in haemopoietic cells, acts by hydrolysing the 5-phosphates from PtdIns(3,4,5)P(3) and Ins(1,3,4,5)P(4 ... [more ▼]

SHIP1 [SH2 (Src homology 2)-containing inositol phosphatase-1], an inositol 5-phosphatase expressed in haemopoietic cells, acts by hydrolysing the 5-phosphates from PtdIns(3,4,5)P(3) and Ins(1,3,4,5)P(4), thereby negatively regulating the PI3K (phosphoinositide 3-kinase) pathway. SHIP1 plays a major role in inhibiting proliferation of myeloid cells. As a result, SHIP1(-/-) mice have an increased number of neutrophils and monocytes/macrophages due to enhanced survival and proliferation of their progenitors. Although SHIP1 contributes to PtdIns(3,4,5)P(3) metabolism in T-lymphocytes, its exact role in this cell type is much less explored. Jurkat cells have recently emerged as an interesting tool to study SHIP1 function in T-cells because they do not express SHIP1 at the protein level, thereby allowing reintroduction experiments in a relatively easy-to-use system. Data obtained from SHIP1 reintroduction have revealed that SHIP1 not only acts as a negative player in T-cell lines proliferation, but also regulates critical pathways, such as NF-kappaB (nuclear factor kappaB) activation, and also appears to remarkably inhibit T-cell apoptosis. On the other hand, experiments using primary T-cells from SHIP1(-/-) mice have highlighted a new role for SHIP1 in regulatory T-cell development, but also emphasize that this protein is not required for T-cell proliferation. In support of these results, SHIP1(-/-) mice are lymphopenic, suggesting that SHIP1 function in T-cells differs from its role in the myeloid lineage. [less ▲]

The Role of Sleep in Motor Memory Consolidation assessed by fMRI and MEG

in Journal of Neuroscience (2007), 27(Suppl. 1),

The role of sleep in the consolidation of emotional memories in humans : a fMRI study

Poster (2006)

The role of soil-root interface for transport processes in soils

in Abstracts AGU (2011)

Role of Sox 10 in the development of the inner ear

Poster (2006)

The Role of Stroma in Breast Carcinoma Growth in Vivo

in Journal of Mammary Gland Biology & Neoplasia (1998), 3(2), 215-25

The malignant progression of tumors is thought to be related to the expression of oncogenes and loss of expression of tumor suppressor gene. These factors are intrinsic to the cancer cells themselves ... [more ▼]

The malignant progression of tumors is thought to be related to the expression of oncogenes and loss of expression of tumor suppressor gene. These factors are intrinsic to the cancer cells themselves. However, carcinomas are also infiltrated by host cells (fibroblasts, endothelial cells, inflammatory cells) and surrounded by an extracellular matrix which is extensively remodeled. The extracellular matrix components and infiltrating host cells provide a microenvironment that conditions both tumor progression and the metastatic process. Transplantation of human tumors into athymic nude mice has become an important experimental approach to study the biology of human cancers. The different models developed so far are beginning to elucidate the role of matrix molecules, growth factors and enzymes as well as fibroblasts in tumor progression. These animal models are likely to provide a useful tool to evaluate new antitumor treatments. [less ▲]

Role of Substance P and Tachykinin Receptor Antagonists in Citric Acid-Induced Cough in Pigs

in European Journal of Pharmacology (2000), 408(3), 305-312

The purpose of this work was to investigate the role of tachykinins in cough induced by citric acid (0.8 M) in pigs. With this object, we have studied the effect of citric acid on substance P content in ... [more ▼]

The purpose of this work was to investigate the role of tachykinins in cough induced by citric acid (0.8 M) in pigs. With this object, we have studied the effect of citric acid on substance P content in the tracheo-bronchial tree and the effects of substance P and of tachykinin receptor antagonists on citric acid-induced cough. Citric acid exposure significantly increased substance P concentration in both broncho-alveolar and tracheal lavage fluids, while it decreased significantly the substance P content in tracheal mucosa. Substance P did not elicit cough, but significantly potentiated the citric acid-induced cough frequency. Tachykinin NK(1), NK(2) or NK(3) receptor antagonists, SR 140333 (nolpitantium), SR 48968 (saredutant) and SR 142801 (osanetant), respectively, significantly inhibited citric acid-induced cough. The same inhibitory effect of tachykinin receptor antagonists was observed, when substance P was nebulised before citric acid challenge. We conclude that citric acid induces in pigs a release of substance P in the tracheo-bronchial tree, which plays a sensitising role on the cough reflex. The involvement of tachykinin NK(1), NK(2), NK(3) receptors are also demonstrated in this reflex. [less ▲]

The role of taurine in ethanol reinforcing effects

in Alcoholism, Clinical & Experimental Research (1998), 22

The role of TGF-alpha in resistance to mesothelioma chemotherapy

Diverse speeche and writing (2012)

Role of TGF-beta1-independent changes in protein neosynthesis, p38alphaMAPK, and cdc42 in hydrogen peroxide-induced senescence-like morphogenesis.

in Free Radical Biology & Medicine (2008), 44(9), 1732-51

The role of TGF-beta1 in hydrogen peroxide-induced senescence-like morphogenesis has been described. The aim of this work was to investigate whether TGF-beta1-independent changes in protein synthesis are ... [more ▼]

The role of TGF-beta1 in hydrogen peroxide-induced senescence-like morphogenesis has been described. The aim of this work was to investigate whether TGF-beta1-independent changes in protein synthesis are involved in this morphogenesis and to study possible mechanisms occurring earlier than TGF-beta1 overexpression. Among the multiple TGF-beta1-independent changes in protein neosynthesis, followed or not by posttranslational modifications, identified by proteomic analysis herein, those of ezrin, L-caldesmon, and HSP27 were particularly studied. Rho-GTPase cdc42 was shown to be responsible for p38(MAPK) activation, in turn triggering phosphorylation of L-caldesmon and HSP27. Cdc42 was also shown to be mainly responsible for the increase in TGF-beta1 mRNA level observed at 24 h after treatment with H(2)O(2) and onward. This study further clarified the mechanisms of senescence-like morphogenesis in addition to the previously demonstrated role of TGF-beta1 signaling pathways. [less ▲]