References of "Erneux, C"
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See detailSHIP2 signaling in normal and pathological situations: Its impact on cell proliferation.
Elong Edimo, W; Schurmans, Stéphane ULg; Roger, PP et al

in Advances in Biological Regulation (2014), 54

Phosphoinositide 5-phosphatases are critical enzymes in modulating the concentrations of PI(3,4,5)P3, PI(4,5)P2 and PI(3,5)P2. The SH2 domain containing inositol 5-phosphatases SHIP1 and SHIP2 belong to ... [more ▼]

Phosphoinositide 5-phosphatases are critical enzymes in modulating the concentrations of PI(3,4,5)P3, PI(4,5)P2 and PI(3,5)P2. The SH2 domain containing inositol 5-phosphatases SHIP1 and SHIP2 belong to this family of enzymes that dephosphorylate the 5 position of PI(3,4,5)P3 to produce PI(3,4)P2. Data obtained in zebrafish and in mice have shown that SHIP2 is critical in development and growth. Exome sequencing identifies mutations in the coding region of SHIP2 as a cause of opsismodysplasia, a severe but rare chondrodysplasia in human. SHIP2 has been reported to have both protumorigenic and tumor suppressor function in human cancer very much depending on the cell model. This could be linked to the relative importance of PI(3,4)P2 (a product of SHIP2 phosphatase activity) which is also controlled by the PI 4-phosphatase and tumor suppressor INPP4B. In the glioblastoma cell line 1321 N1, that do not express PTEN, lowering SHIP2 expression has an impact on the levels of PI(3,4,5)P3, cell morphology and cell proliferation. It positively stimulates cell proliferation by decreasing the expression of key regulatory proteins of the cell cycle such as p27. Together the data point out to a role of SHIP2 in development in normal cells and at least in cell proliferation in some cancer derived cells. [less ▲]

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See detailInositol trisphosphate 3-kinase B is increased in human Alzheimer brain and exacerbates mouse Alzheimer pathology
Stygelbout, V.; Leroy, K.; Pouillon, V. et al

in Brain : A Journal of Neurology (2014), 137

S. Schurmans and J.-P. Brion contributed equally to this work Corresponding author: S. Schurmans, Laboratoire de Génétique Fonctionnelle, GIGA-Research Centre, Building 34, Université de Liège, rue de ... [more ▼]

S. Schurmans and J.-P. Brion contributed equally to this work Corresponding author: S. Schurmans, Laboratoire de Génétique Fonctionnelle, GIGA-Research Centre, Building 34, Université de Liège, rue de l’Hôpital 1, 4000-Liège, Belgium. Abstract: Inositol (1,4,5) trisphosphate 3-kinase B phosphorylates inositol 1,4,5-trisphosphate into inositol 1,3,4,5-tetrakisphosphate and controls signal transduction in various hematopoietic cells. Surprisingly, it has been reported that Inositol (1,4,5) trisphosphate 3-kinase B mRNA level is significantly increased in the cerebral cortex of Alzheimer patients, compared to control subjects. Since Extracellular signal-regulated kinases 1/2 activation is increased in Alzheimer brain and since Inositol (1,4,5) trisphosphate 3-kinase B is a regulator of Extracellular signal-regulated kinases 1/2 activation in some hematopoietic cells, we tested whether this increased activation in Alzheimer’s disease might be related to an increased activity of Inositol (1,4,5) trisphosphate 3-kinase B. We show here that Inositol (1,4,5) trisphosphate 3-kinase B protein level was 3 fold increased in the cerebral cortex of most Alzheimer patients, compared to control subjects, and accumulated in dystrophic neurites associated to amyloid plaques. In mouse Neuro-2a neuroblastoma cells, Inositol (1,4,5) trisphosphate 3-kinase B overexpression was associated with increased cell apoptosis and increased β-secretase 1 activity leading to amyloid-β peptides overproduction. In this cellular model, an inhibitor of Mitogen-activated kinase kinases 1/2 completely prevented amyloid-β peptides overproduction. Transgenic overexpression of Inositol (1,4,5) trisphosphate 3-kinase B in mouse forebrain neurons was not sufficient to induce amyloid plaques formation or TAU hyperphosphorylation. However, in the 5X Familial Alzheimer’s Disease mouse model, neuronal Inositol (1,4,5) trisphosphate 3-kinase B overexpression significantly increased Extracellular signal-regulated kinases 1/2 activation and β-secretase 1 activity, resulting in exacerbated Alzheimer pathology as shown by increased astrogliosis, amyloid-β40 peptide production and TAU hyperphosphorylation. No impact on pathology was observed in the 5X Familial Alzheimer’s Disease mouse model when a catalytically inactive Inositol (1,4,5) trisphosphate 3-kinase B protein was overexpressed. Together, our results point to the Inositol (1,4,5) trisphosphate 3-kinase B /Inositol 1,3,4,5-tetrakisphosphate/Extracellular signal-regulated kinases 1/2 signaling pathway as an important regulator of neuronal cell apoptosis, Amyloid precursor protein processing and TAU phosphorylation in Alzheimer’s disease, and suggest that Inositol (1,4,5) trisphosphate 3-kinase B could represent a new target for reducing pathology in human AD patients with increased cortical Inositol (1,4,5) trisphosphate 3-kinase B expression. [less ▲]

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See detailDevelopmental defects and rescue from glucose intolerance of a catalytically-inactive novel Ship2 mutant mouse
Dubois, E; Jacoby, M; Blockmans, M et al

in Cellular Signalling (2012), 24

The function of the phosphoinositide 5-phosphatase Ship2 was investigated in a new mouse model expressing a germline catalytically-inactive Ship2∆/∆ mutant protein. Ship2∆/∆ mice were viable with defects ... [more ▼]

The function of the phosphoinositide 5-phosphatase Ship2 was investigated in a new mouse model expressing a germline catalytically-inactive Ship2∆/∆ mutant protein. Ship2∆/∆ mice were viable with defects in somatic growth and in development of muscle, adipose tissue and female genital tract. Lipid metabolism and insulin secretion were also affected in these mice, but glucose tolerance, insulin sensitivity and insulin-induced PKB phosphorylation were not. We expected that the expression of the catalytically inactive Ship2 protein in PI 3’-kinase-defective p110αD933A/+ mice would counterbalance the phenotypes of parental mice by restoring normal PKB signaling but, for most of the parameters tested, this was not the case. Indeed, often, the Ship2∆/∆ phenotype had a dominant effect over the p110αD933A/+ phenotype and, sometimes, there was a surprising additive effect of both mutations. p110αD933A/+Ship2∆/∆ mice still displayed a reduced PKB phosphorylation in response to insulin, compared to wild type mice yet had a normal glucose tolerance and insulin sensitivity, like the Ship2∆/∆ mice. Together, our results suggest that the Ship2∆/∆ phenotype is not dependent on an overstimulated class I PI 3-kinase-PKB signaling pathway and thus, indirectly, that it may be more dependent on the lack of Ship2-produced phosphatidylinositol 3,4-bisphosphate and derived phosphoinositides. [less ▲]

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See detailThe inositol Inpp5k 5-phosphatase affects osmoregulation through the vasopressin-aquaporin 2 pathway in the collecting system.
Pernot, E.; Terryn, S.; Cheong, S. C. et al

in Pflügers Archiv : European Journal of Physiology (2011), 462

Inositol Inpp5k (or Pps, SKIP) is a member of the inositol polyphosphate 5-phosphatases family with a poorly characterized function in vivo. In this study, we explored the function of this inositol 5 ... [more ▼]

Inositol Inpp5k (or Pps, SKIP) is a member of the inositol polyphosphate 5-phosphatases family with a poorly characterized function in vivo. In this study, we explored the function of this inositol 5-phosphatase in mice and cells overexpressing the 42-kDa mouse Inpp5k protein. Inpp5k transgenic mice present defects in water metabolism characterized by a reduced plasma osmolality at baseline, a delayed urinary water excretion following a water load, and an increased acute response to vasopressin. These defects are associated with the expression of the Inpp5k transgene in renal collecting ducts and with alterations in the arginine vasopressin/aquaporin-2 signalling pathway in this tubular segment. Analysis in a mouse collecting duct mCCD cell line revealed that Inpp5k overexpression leads to increased expression of the arginine vasopressin receptor type 2 and increased cAMP response to arginine vasopressin, providing a basis for increased aquaporin-2 expression and plasma membrane localization with increased osmotically induced water transport. Altogether, our results indicate that Inpp5k 5-phosphatase is important for the control of the arginine vasopressin/aquaporin-2 signalling pathway and water transport in kidney collecting ducts. [less ▲]

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See detailInositol trisphosphate 3-kinase B (InsP3KB) as a physiological modulator of myelopoiesis
Jia, Y.; Loison, F.; Erneux, C. et al

in Proceedings of the National Academy of Sciences of the United States of America (2008), 105

Inositol trisphosphate 3-kinase B (InsP3KB) belongs to a family of kinases that convert inositol 1,4,5-trisphosphate (Ins(1,4,5)P3 or IP3) to inositol 1,3,4,5-tetrakisphosphate (Ins(1,3,4,5)P4). Previous ... [more ▼]

Inositol trisphosphate 3-kinase B (InsP3KB) belongs to a family of kinases that convert inositol 1,4,5-trisphosphate (Ins(1,4,5)P3 or IP3) to inositol 1,3,4,5-tetrakisphosphate (Ins(1,3,4,5)P4). Previous studies have shown that disruption of InsP3KB leads to impaired T cell and B cell development as well as hyperactivation of neutrophils. Here, we demonstrate that InsP3KB is also a physiological modulator of myelopoiesis. The InsP3KB gene is expressed in all hematopoietic stem/progenitor cell populations. In InsP3KB null mice, the bone marrow granulocyte monocyte progenitor (GMP) population was expanded, and GMP cells proliferated significantly faster. Consequently, neutrophil production in the bone marrow was enhanced, and the peripheral blood neutrophil count was also substantially elevated in these mice. These effects might be due to enhancement of PtdIns(3,4,5)P3/Akt signaling in the InsP3KB null cells. Phosphorylation of cell cycle-inhibitory protein p21(cip1), one of the downstream targets of Akt, was augmented, which can lead to the suppression of the cell cycle-inhibitory effect of p21 [less ▲]

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See detailInositol 1,3,4,5-tetrakisphosphate controls proapoptotic Bim gene expression and survival in B cells.
Maréchal, Y.; Pesesse, X.; Jia, Y. et al

in Proceedings of the National Academy of Sciences of the United States of America (2007), 104

The contribution of the B isoform of inositol 1,4,5-trisphosphate [Ins(1,4,5)P(3)] 3-kinase (or Itpkb) and inositol 1,3,4,5-tetrakisphosphate [Ins(1,3,4,5)P(4)], its reaction product, to B cell function ... [more ▼]

The contribution of the B isoform of inositol 1,4,5-trisphosphate [Ins(1,4,5)P(3)] 3-kinase (or Itpkb) and inositol 1,3,4,5-tetrakisphosphate [Ins(1,3,4,5)P(4)], its reaction product, to B cell function and development remains unknown. Here, we show that mice deficient in Itpkb have defects in B cell survival leading to specific and intrinsic developmental alterations in the B cell lineage and antigen unresponsiveness in vivo. The decreased B cell survival is associated with a decreased phosphorylation of Erk1/2 and increased Bim gene expression. B cell survival, development, and antigen responsiveness are normalized in parallel to reduced expression of Bim in Itpkb(-/-) Bim(+/-) mice. Analysis of the signaling pathway downstream of Itpkb revealed that Ins(1,3,4,5)P(4) regulates subcellular distribution of Rasa3, a Ras GTPase-activating protein acting as an Ins(1,3,4,5)P(4) receptor. Together, our results indicate that Itpkb and Ins(1,3,4,5)P(4) mediate a survival signal in B cells via a Rasa3-Erk signaling pathway controlling proapoptotic Bim gene expression [less ▲]

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See detailIns(1,3,4,5)P4 negatively regulates PtdIns(3,4,5)P3 signaling in neutrophils
Jia, Y.; Subramanian, K. K.; Erneux, C. et al

in Immunity (2007), 27

Many neutrophil functions are regulated by phosphatidylinositol-3,4,5-trisphosphate (PtdIns(3,4,5)P3) that mediates protein membrane translocation via binding to pleckstrin homolog (PH) domains within ... [more ▼]

Many neutrophil functions are regulated by phosphatidylinositol-3,4,5-trisphosphate (PtdIns(3,4,5)P3) that mediates protein membrane translocation via binding to pleckstrin homolog (PH) domains within target proteins. Here we show that inositol 1,3,4,5-tetrakisphosphate(Ins(1,3,4,5)P4), a cytosolic small molecule, bound the same PH domain of target proteins and competed for binding to PtdIns(3,4,5)P3. In neutrophils, chemoattractant stimulation triggered rapid elevation in Ins(1,3,4,5)P4 concentration. Depletion of Ins(1,3,4,5)P4 by deleting the gene encoding InsP3KB, which converts Ins(1,4,5)P3 to Ins(1,3,4,5)P4, enhanced membrane translocation of the PtdIns(3,4,5)P3-specific PH domain. This led to enhanced sensitivity to chemoattractant stimulation, elevated superoxide production, and enhanced neutrophil recruitment to inflamed peritoneal cavity. On the contrary, augmentation of intracellular Ins(1,3,4,5)P4 concentrationblockedPHdomainmediated membrane translocation of target proteins and dramatically decreased the sensitivity of neutrophils to chemoattractant stimulation. These findings establish a role for Ins(1,3,4,5)P4 in cellular signal transduction pathways and provide another mechanism for modulating PtdIns(3,4,5)P3 signaling in neutrophils. [less ▲]

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See detailSHIP2 controls PtdIns(3,4,5)P3 and PKB activity in response to oxidative stress
Zhang, J.; Liu, Z.; Rasschaert, J. et al

in Cellular Signalling (2007), 19

Reactive oxygen species (ROS) are known to be involved in redox signalling pathways that may contribute to normal cell function as well as disease progression. The tumour suppressor PTEN and the inositol ... [more ▼]

Reactive oxygen species (ROS) are known to be involved in redox signalling pathways that may contribute to normal cell function as well as disease progression. The tumour suppressor PTEN and the inositol 5-phosphatase SHIP2 are critical enzymes in the control of PtdIns(3,4,5)P(3) level. It has been reported that oxidants, including those produced in cells such as macrophages, can activate downstream signalling via the inactivation of PTEN. The present study evaluates the potential impact of SHIP2 on phosphoinositides in cells exposed to sodium peroxide. We used a model of SHIP2 deficient mouse embryonic fibroblasts (MEFs) stimulated by H(2)O(2): at 15 min, PtdIns(3,4,5)P(3) was markedly increased in SHIP2 -/- cells as compared to +/+ cells. In contrast, no significant increase in PtdIns(3,4)P(2) could be detected at 15 or 120 min incubation of the cells with H(2)O(2) (0.6 mM). PKB activity was also upregulated in SHIP2 -/- cells as compared to +/+ cells in response to H(2)O(2). SHIP2 add back experiments in SHIP2 -/- cells confirm its critical role as a lipid phosphatase in the control of PtdIns(3,4,5)P(3) level in response to H(2)O(2). We conclude that SHIP2 lipid phosphatase activity plays an important role in the metabolism PtdIns(3,4,5)P(3) which is demonstrated in oxygen stressed cells [less ▲]

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See detailThe absence of expression of the three isoenzymes of inositol 1,4,5-trisphosphate 3-kinase does not prevent the formation of inositol pentakisphosphate and hexakisphosphate in mouse embryonic fibroblasts
Leyman, A.; Pouillon, V.; Bostan, A. et al

in Cellular Signalling (2007), 19

The activation of phospholipase C leads to the formation of both I(1,4,5)P(3) and diacylglycerol (DAG). I(1,4,5)P(3) can be metabolized by dephosphorylation catalyzed by Type I I(1,4,5)P(3) 5-phosphatase ... [more ▼]

The activation of phospholipase C leads to the formation of both I(1,4,5)P(3) and diacylglycerol (DAG). I(1,4,5)P(3) can be metabolized by dephosphorylation catalyzed by Type I I(1,4,5)P(3) 5-phosphatase and by enzymatic phosphorylation to various inositol phosphates. This last step is catalyzed by three mammalian isoenzymes that specifically phosphorylate the 3-phosphate position of the inositol ring Itpka, Itpkb and Itpkc and a less specific enzyme Ipmk (or inositol multikinase) that phosphorylates I(1,4,5)P(3) at the D-3 and D-6 positions. This study was performed in mice cells in order to understand the synthetic pathway of IP5 and IP6 following PLC stimulation and possible link with Itpk activity. Mouse embryonic fibroblasts (MEF) were prepared from Itpkb(-/-) Itpkc(-/-) mice. Western blot and RT-PCR analysis show that the cells do not express Itpka. In contrast, they do express Ipmk. The cells still produce IP5 and IP6. Our data show that the absence of expression of the three isoenzymes of Itpk does not prevent the formation of IP5 and IP6, at least in mouse embryonic fibroblasts. The nuclear Ipmk plays therefore a critical role in the metabolism of I(1,4,5)P(3) and production of highly phosphorylated IP5 and IP6 [less ▲]

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See detailPhosphoinositide phosphatases in a network of signaling reactions
Blero, D.; Payrastre, B.; Schurmans, Stéphane ULg et al

in Pflügers Archiv : European Journal of Physiology (2007), 455

Phosphoinositide phosphatases dephosphorylate the three positions (D-3, 4 and 5) of the inositol ring of the poly-phosphoinositides. They belong to different families of enzymes. The PtdIns(3,4)P(2) 4 ... [more ▼]

Phosphoinositide phosphatases dephosphorylate the three positions (D-3, 4 and 5) of the inositol ring of the poly-phosphoinositides. They belong to different families of enzymes. The PtdIns(3,4)P(2) 4-phosphatase family, the tumour suppressor phosphatase and tensin homolog deleted on chromosome 10 (PTEN), SAC1 domain phosphatases and myotubularins belong to the tyrosine protein phosphatases superfamily. They share the presence of a conserved cysteine residue in the consensus CX(5)RT/S. Another family consists of the inositol polyphosphate 5-phosphatase isoenzymes. The importance of these phosphoinositide phosphatases in cell regulation is illustrated by multiple examples of their implications in human diseases such as Lowe syndrome, X-linked myotubular myopathy, cancer, diabetes or bacterial infection [less ▲]

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See detailPhosphatidylinositol 3,4,5-trisphosphate modulation in Ship2-deficient mouse embryonic fibroblasts
Blero, D.; Zhang, J.; Pesesse, X. et al

in FEBS Journal (2005), 272

SHIP2, the ubiquitous SH2 domain containing inositol 5-phosphatase, includes a series of protein interacting domains and has the ability to dephosphorylate phosphatidylinositol 3,4,5-trisphosphate [PtdIns ... [more ▼]

SHIP2, the ubiquitous SH2 domain containing inositol 5-phosphatase, includes a series of protein interacting domains and has the ability to dephosphorylate phosphatidylinositol 3,4,5-trisphosphate [PtdIns(3,4,5)P3] in vitro. The present study, which was undertaken to evaluate the impact of SHIP2 on PtdIns(3,4,5)P3 levels, was performed in a mouse embryonic fibroblast (MEF) model using SHIP2 deficient (– ⁄ –) MEF cells derived from knockout mice. PtdIns(3,4,5)P3 was upregulated in serum stimulated – ⁄ – MEF cells as compared to +⁄+ MEF cells. Although the absence of SHIP2 had no effect on basal PtdIns(3,4,5)P3 levels, we show here that this lipid was significantly upregulated in SHIP2 – ⁄ – cells but only after short-term (i.e. 5–10 min) incubation with serum. The difference in PtdIns(3,4,5)P3 levels in heterozygous fibroblast cells was intermediate between the +⁄+ and the – ⁄ – cells. In our model, insulin-like growth factor-1 stimulation did not show this upregulation. Serum stimulated phosphoinositide 3-kinase (PI 3-kinase) activity appeared to be comparable between +⁄+ and – ⁄ – cells. Moreover, protein kinase B, but not mitogen activated protein kinase activity, was also potentiated in SHIP2 deficient cells stimulated by serum. The upregulation of protein kinase B activity in serum stimulated cells was totally reversed in the presence of the PI 3-kinase inhibitor LY-294002, in both +⁄+ and – ⁄ – cells. Altogether, these data establish a link between SHIP2 and the acute control of PtdIns(3,4,5)P3 levels in intact cells [less ▲]

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See detailCorrigenda: The lipid phosphatase SHIP2 controls insulin sensitivity
Clément, S.; Krause, U.; Desmedt, F. et al

in Nature (2004), 431

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See detailInositol 1,3,4,5-tetrakisphosphate is essential for normal T lymphocyte development
Pouillon, V.; Hascakova-Bartova, R.; Pajak, B. et al

in Nature Immunology (2003), 4

Inositol 1,4,5-trisphosphate (Ins(1,4,5)P(3)) is phosphorylated by Ins(1,4,5)P(3) 3-kinase, generating inositol 1,3,4,5-tetrakisphosphate (Ins(1,3,4,5)P(4)). The physiological function of Ins(1,3,4,5)P(4 ... [more ▼]

Inositol 1,4,5-trisphosphate (Ins(1,4,5)P(3)) is phosphorylated by Ins(1,4,5)P(3) 3-kinase, generating inositol 1,3,4,5-tetrakisphosphate (Ins(1,3,4,5)P(4)). The physiological function of Ins(1,3,4,5)P(4) is still unclear, but it has been reported to be a potential modulator of calcium mobilization. Disruption of the gene encoding the ubiquitously expressed Ins(1,4,5)P(3) 3-kinase isoform B (Itpkb) in mice caused a severe T cell deficiency due to major alterations in thymocyte responsiveness and selection. However, we were unable to detect substantial defects in Ins(1,4,5)P(3) amounts or calcium mobilization in Itpkb(-/-) thymocytes. These data indicate that Itpkb and Ins(1,3,4,5)P(4) define an essential signaling pathway for T cell precursor responsiveness and development [less ▲]

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See detailSH2 domain containing inositol 5-phosphatases 1 and 2 in blood platelets: interaction and respective role in the control of phosphatidylinositol 3,4,5-trisphosphate levels
Giuriato, S.; Pesesse, X.; Bodin, S. et al

in Biochemical Journal (2003), 376

Src homology domain 2-containing inositol 5-phosphatases 1 and 2 (SHIP1 and SHIP2) are capable of dephosphorylating the second messenger PtdIns(3,4,5) P3 (phosphatidylinositol 3,4,5-trisphosphate) and ... [more ▼]

Src homology domain 2-containing inositol 5-phosphatases 1 and 2 (SHIP1 and SHIP2) are capable of dephosphorylating the second messenger PtdIns(3,4,5) P3 (phosphatidylinositol 3,4,5-trisphosphate) and interacting with several signalling proteins. SHIP1 is essentially expressed in haematopoietic cells, whereas SHIP2, a closely related enzyme, is ubiquitous. In the present study, we show that SHIP1 and SHIP2 are expressed as functional PtdIns(3,4,5) P3 5-phosphatases in human blood platelets and are capable of interacting when these two lipid phosphatases are co-expressed, either naturally (platelets and A20 B lymphoma cells) or artificially (COS-7 cells). Using COS-7 cells transfected with deletion mutants of SHIP2, we demonstrate that the Src homology domain 2 of SHIP2 is the minimal and sufficient protein motif responsible for the interaction between the two phosphatases. These results prompted us to investigate the relative importance of SHIP1 and SHIP2 in the control of PtdIns(3,4,5) P3 levels in platelets using homozygous or heterozygous SHIP1- or SHIP2-deficient mice. Our results strongly suggest that SHIP1, rather than SHIP2, plays a major role in controlling PtdIns(3,4,5) P3 levels in response to thrombin or collagen activation of mouse blood platelets [less ▲]

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See detailThe lipid phosphatase SHIP2 controls insulin sensitivity
Clément, S.; Krause, U.; Desmedt, F. et al

in Nature (2001), 409

Insulin is the primary hormone involved in glucose homeostasis, and impairment of insulin action and/or secretion has a critical role in the pathogenesis of diabetes mellitus. Type-II SH2-domain ... [more ▼]

Insulin is the primary hormone involved in glucose homeostasis, and impairment of insulin action and/or secretion has a critical role in the pathogenesis of diabetes mellitus. Type-II SH2-domain-containing inositol 5-phosphatase, or 'SHIP2', is a member of the inositol polyphosphate 5-phosphatase family. In vitro studies have shown that SHIP2, in response to stimulation by numerous growth factors and insulin, is closely linked to signalling events mediated by both phosphoinositide-3-OH kinase and Ras/mitogen-activated protein kinase. Here we report the generation of mice lacking the SHIP2 gene. Loss of SHIP2 leads to increased sensitivity to insulin, which is characterized by severe neonatal hypoglycaemia, deregulated expression of the genes involved in gluconeogenesis, and perinatal death. Adult mice that are heterozygous for the SHIP2 mutation have increased glucose tolerance and insulin sensitivity associated with an increased recruitment of the GLUT4 glucose transporter and increased glycogen synthesis in skeletal muscles. Our results show that SHIP2 is a potent negative regulator of insulin signalling and insulin sensitivity in vivo [less ▲]

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