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Angela Corcelli - One of the best experts on this subject based on the ideXlab platform.
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Osmotic Shock stimulates de novo synthesis of two cardiolipins in an extreme halophilic archaeon
Journal of Lipid Research, 2004Co-Authors: Patrizia Lopalco, Simona Lobasso, Francesco Babudri, Angela CorcelliAbstract:The present report illustrates the response to Osmotic stress of an extreme halophilic archaeon, Halorubrum sp., isolated from the saltern ponds of Margherita di Savoia in southern Italy. The hypotonic stress induces relevant changes in the membrane lipid composition: archaeal cardiolipin content markedly increases, whereas phosphatidylglycerol (PG) decreases. Membranes isolated from this archaeon after cell disruption by Osmotic Shock are highly enriched in archaeal cardiolipin and reveal the presence of a novel phospholipid. Electrospray ionization mass spectrometry and NMR analyses revealed that this novel lipid has the structure of a sulfo-diglyco-diether-phosphatidic acid, i.e., a phospholipid dimer or a novel cardiolipin analogue. As NMR analyses showed that the sugars in the novel phospholipid dimer are the same and in the same order of a sulfated diglycosyl diphytanylglycerol diether (S-DGD-5) present as a major lipid component in the archaeon membranes, the novel phospholipid dimer was named S-DGD-5-PA. We conclude that Osmotic Shock induces a specific increase in the membrane content of the two cardiolipins and suggest that PG and S-DGD-5 are intermediates for the de novo synthesis of archaeal cardiolipin and S-DGD-5-PA, respectively.
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Osmotic Shock induces the presence of glycocardiolipin in the purple membrane of halobacterium salinarum
Journal of Lipid Research, 2003Co-Authors: Simona Lobasso, Veronica M T Lattanzio, Patrizia Lopalco, Angela CorcelliAbstract:In the purple membrane (PM) of Halobacterium salinarum is present a phospholipid dimer consisting of sulfo-triglycosyl-diether (S-TGD-1) esterified to the phosphate group of phosphatidic acid (PA), i.e., S-TGD-1-PA, called glycocardiolipin (GlyC) (Corcelli, A., M. Colella, G. Mascolo, F. P. Fanizzi, and M. Kates. A novel glycolipid and phospholipid in the purple membrane. 2000. Biochemistry. 39: 3318-3326). The GlyC content of whole cells, PM, and other cell fractions of H. salinarum have been analyzed. GlyC is a nonabundant phospholipid in H. salinarum cells, and it represents one of the major phospholipids of isolated PM. In this report, we show that a) GlyC is formed during the isolation of PM, b) GlyC increase in H. salinarum cells is specifically induced by Osmotic Shock, and c) in correspondence with GlyC increase, a decrease of S-TGD-1 levels occurs. The changes in membrane lipid composition observed during the isolation of PM are due to de novo synthesis of GlyC from S-TGD-1.
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Osmotic Shock induces the presence of glycocardiolipin in the purple membrane of halobacterium salinarum
Journal of Lipid Research, 2003Co-Authors: Simona Lobasso, Veronica M T Lattanzio, Patrizia Lopalco, Angela CorcelliAbstract:In the purple membrane (PM) of Halobacterium salinarum is present a phospholipid dimer consisting of sulfo-triglycosyl-diether (S-TGD-1) esterified to the phos- phate group of phosphatidic acid (PA), i.e., S-TGD-1-PA, called glycocardiolipin (GlyC) (Corcelli, A., M. Colella, G. Mascolo, F. P. Fanizzi, and M. Kates. A novel glycolipid and phospholipid in the purple membrane. 2000. Biochemistry. 39: 3318-3326). The GlyC content of whole cells, PM, and other cell fractions of H. salinarum have been analyzed. GlyC is a nonabundant phospholipid in H. salinarum cells, and it represents one of the major phospholipids of iso- lated PM. In this report, we show that a ) GlyC is formed during the isolation of PM, b ) GlyC increase in H. salinarum cells is specifically induced by Osmotic Shock, and c ) in cor- respondence with GlyC increase, a decrease of S-TGD-1 lev- els occurs. The changes in membrane lipid composition ob- served during the isolation of PM are due to de novo synthesis of GlyC from S-TGD-1. —Lobasso S., P. Lopalco, V. M. T. Lattanzio, and A. Corcelli. Osmotic Shock induces the presence of glycocardiolipin in the purple membrane of Halobacterium salinarum . J. Lipid. Res. 2003. 44: 2120-2126.
Eisuke Nishida - One of the best experts on this subject based on the ideXlab platform.
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purification and identification of a major activator for p38 from Osmotically Shocked cells activation of mitogen activated protein kinase kinase 6 by Osmotic Shock tumor necrosis factor alpha and h2o2
Journal of Biological Chemistry, 1996Co-Authors: Tetsuo Moriguchi, Yukiko Gotoh, Fumiko Toyoshima, Akihiro Iwamatsu, Kenji Irie, Eiji Mori, Noriyo Kuroyanagi, Masatoshi Hagiwara, Kunihiro Matsumoto, Eisuke NishidaAbstract:A stress-activated, serine/threonine kinase, p38 (also known as HOG1 or MPK2) belongs to a subgroup of mitogen-activated protein kinase (MAPK) superfamily molecules. An activity to activate p38 (p38 activator activity) as well as p38 activity itself were greatly stimulated by hyperosmolar media in mouse lymphoma L5178Y cells. The activator activity has been purified by sequential chromatography. A 36-kDa polypeptide that was coeluted with the activity in the final chromatography step was identified as MAPK kinase 6 (MAPKK6) by protein microsequencing analysis. Monoclonal and polyclonal antibodies raised against recombinant MAPKK6 recognized specifically the 36-kDa MAPKK6 protein but did not cross-react with MKK3 proteins. The use of these anti-MAPKK6 antibodies revealed that two major peaks of the p38 activator activity in the first chromatography step reside in the activated MAPKK6. Using a genetic screen in yeast, we isolated MKK3b, an alternatively spliced form of MKK3. Like MKK3 and MAPKK6, MKK3b was shown to be a specific activator for p38 and was activated by Osmotic Shock when expressed in COS7 cells. Immunoblotting analysis revealed that MAPKK6 is expressed highly in HeLa and KB cells and scarcely in PC12 cells, whereas MKK3 and MKK3b are expressed in all cells examined. Immunodepletion of MAPKK6 from the extracts obtained from L5178Y cells and KB cells exposed to hyperosmolar media depleted them of almost all of the p38 activator activity, indicating that MAPKK6 is a major activator for p38 in an osmosensing pathway in these cells. In addition, MAPKK6 was activated strongly by tumor necrosis factor-α, H2O2, and okadaic acid and moderately by cycloheximide in KB cells. Thus, there are at least three members of p38 activator, MKK3, MKK3b, and MAPKK6, and MAPKK6 may function as a major activator for p38 when expressed.
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activation of protein kinase cascades by Osmotic Shock
Journal of Biological Chemistry, 1995Co-Authors: Satoshi Matsuda, Hiroshi Kawasaki, Tetsuo Moriguchi, Yukiko Gotoh, Eisuke NishidaAbstract:Osmotic Shock induces a variety of biochemical and physiological responses in vertebrate cells. By analyzing extracts obtained from rat 3Y1 fibroblastic cells exposed to hyper-osmolar media, we have found that mitogen-activated protein kinases (MAPKs) and stress-activated protein kinases (SAPKs, also known as JNKs) are both activated in response to Osmotic Shock. MAPKK1 (MEK1) was also activated markedly. Furthermore, Raf-1 and MEKK were activated strikingly by the Osmotic Shock. Activation of Raf-1 and MEKK in response to Osmotic Shock was detected also in PC12 cells, in which MEKK activation by the Osmotic Shock was much stronger than that by epidermal growth factor. Activation of SAPKs in PC12 cells by the Osmotic Shock was also more marked than that by epidermal growth factor. The activated MEKK phosphorylated not only MAPKKs but also XMEK2, which is distantly related to MAPKK. Recombinant wild-type XMEK2, but not kinase-negative XMEK2, was able to phosphorylate and activate recombinant SAPK alpha in vitro. In addition, this activity of XMEK2 was activated by the activated MEKK. These results suggest that the MAPK cascade consisting of Raf-1, MAPKK, and MAPK and the SAPK cascade consisting of MEKK, XMEK2, and SAPK are both activated in response to Osmotic Shock. Finally, it was found that XMEK2 is a good substrate for SAPK.
Jerrold M Olefsky - One of the best experts on this subject based on the ideXlab platform.
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insulin mediated cellular insulin resistance decreases Osmotic Shock induced glucose transport in 3t3 l1 adipocytes
Endocrinology, 2000Co-Authors: Andrej Janez, Dorothy Sears Worrall, Jerrold M OlefskyAbstract:Similar to insulin, Osmotic Shock treatment of 3T3-L1 adipocytes causes translocation of GLUT4 protein to the plasma membrane and an increase in glucose transport activity. In our study, we evaluated the effect of chronic insulin treatment on the Osmotic Shock signaling pathway leading to GLUT4 translocation and glucose uptake. We found that chronic administration of insulin to the adipocytes induced cellular resistance to Osmotic Shock-stimulated GLUT4 translocation and glucose transport. We found that chronic insulin treatment attenuated Shock-induced Gab-1 tyrosine phosphorylation. Furthermore, chronic insulin exposure led to a marked impairment in the ability of Gab-1 to associate with p85 subunit of PI 3-kinase in response to acute Shock and insulin stimulation. Cells that were chronically treated with insulin showed a 70% and a 61% decrease in Gab-1 associated PI 3-kinase activity in Shock- vs. insulin-treated cells, respectively. In addition, we found that chronic insulin treatment inhibited both insulin- and Osmotic Shock-induced membrane ruffling, indicating that two PI 3-kinase dependent effects, GLUT4 translocation and membrane ruffling are decreased in chronically insulin-treated cells. The results described above clearly demonstrate that chronic insulin treatment induces a state of cellular resistance to Osmotic Shock signal transduction. (Endocrinology 141: 4657‐ 4663, 2000)
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the Osmotic Shock induced glucose transport pathway in 3t3 l1 adipocytes is mediated by gab 1 and requires gab 1 associated phosphatidylinositol 3 kinase activity for full activation
Journal of Biological Chemistry, 2000Co-Authors: Andrej Janez, Dorothy Sears Worrall, Takeshi Imamura, Prem M Sharma, Jerrold M OlefskyAbstract:Osmotic Shock treatment of 3T3-L1 adipocytes causes an increase in glucose transport activity and translocation of GLUT4 protein similar to that elicited by insulin treatment. Insulin stimulation of GLUT4 translocation and glucose transport activity was completely inhibited by wortmannin, however, activation by Osmotic Shock was only partially blocked. Additionally, we have found that the newly identified insulin receptor substrate Gab-1 (Grb2-associated binder-1) is tyrosine-phosphorylated following sorbitol stimulation. Treatment of cells with the tyrosine kinase inhibitor genistein inhibited Osmotic Shock-stimulated Gab-1 phosphorylation as well as Shock-induced glucose transport. Furthermore, pretreatment with the selective Src family kinase inhibitor PP2 completely inhibited the ability of sorbitol treatment to cause tyrosine phosphorylation of Gab-1. We have also shown that microinjection of anti-Gab-1 antibody inhibits Osmotic Shock-induced GLUT4 translocation. Furthermore, phosphorylated Gab-1 binds and activates phosphatidylinositol 3-kinase (PI3K) in response to Osmotic Shock. The PI3K activity associated with Gab-1 was 82% of that associated with anti-phosphotyrosine antibodies, indicating that Gab-1 is the major site for PI3K recruitment following Osmotic Shock stimulation. Although wortmannin only causes a partial block of Osmotic Shock-stimulated glucose uptake, wortmannin completely abolishes Gab-1 associated PI3K activity. This suggests that other tyrosine kinase-dependent pathways, in addition to the Gab-1-PI3K pathway, contribute to Osmotic Shock-mediated glucose transport. To date, Gab-1 is the first protein identified as a member of the Osmotic Shock signal transduction pathway.
Simona Lobasso - One of the best experts on this subject based on the ideXlab platform.
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Osmotic Shock stimulates de novo synthesis of two cardiolipins in an extreme halophilic archaeon
Journal of Lipid Research, 2004Co-Authors: Patrizia Lopalco, Simona Lobasso, Francesco Babudri, Angela CorcelliAbstract:The present report illustrates the response to Osmotic stress of an extreme halophilic archaeon, Halorubrum sp., isolated from the saltern ponds of Margherita di Savoia in southern Italy. The hypotonic stress induces relevant changes in the membrane lipid composition: archaeal cardiolipin content markedly increases, whereas phosphatidylglycerol (PG) decreases. Membranes isolated from this archaeon after cell disruption by Osmotic Shock are highly enriched in archaeal cardiolipin and reveal the presence of a novel phospholipid. Electrospray ionization mass spectrometry and NMR analyses revealed that this novel lipid has the structure of a sulfo-diglyco-diether-phosphatidic acid, i.e., a phospholipid dimer or a novel cardiolipin analogue. As NMR analyses showed that the sugars in the novel phospholipid dimer are the same and in the same order of a sulfated diglycosyl diphytanylglycerol diether (S-DGD-5) present as a major lipid component in the archaeon membranes, the novel phospholipid dimer was named S-DGD-5-PA. We conclude that Osmotic Shock induces a specific increase in the membrane content of the two cardiolipins and suggest that PG and S-DGD-5 are intermediates for the de novo synthesis of archaeal cardiolipin and S-DGD-5-PA, respectively.
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Osmotic Shock induces the presence of glycocardiolipin in the purple membrane of halobacterium salinarum
Journal of Lipid Research, 2003Co-Authors: Simona Lobasso, Veronica M T Lattanzio, Patrizia Lopalco, Angela CorcelliAbstract:In the purple membrane (PM) of Halobacterium salinarum is present a phospholipid dimer consisting of sulfo-triglycosyl-diether (S-TGD-1) esterified to the phosphate group of phosphatidic acid (PA), i.e., S-TGD-1-PA, called glycocardiolipin (GlyC) (Corcelli, A., M. Colella, G. Mascolo, F. P. Fanizzi, and M. Kates. A novel glycolipid and phospholipid in the purple membrane. 2000. Biochemistry. 39: 3318-3326). The GlyC content of whole cells, PM, and other cell fractions of H. salinarum have been analyzed. GlyC is a nonabundant phospholipid in H. salinarum cells, and it represents one of the major phospholipids of isolated PM. In this report, we show that a) GlyC is formed during the isolation of PM, b) GlyC increase in H. salinarum cells is specifically induced by Osmotic Shock, and c) in correspondence with GlyC increase, a decrease of S-TGD-1 levels occurs. The changes in membrane lipid composition observed during the isolation of PM are due to de novo synthesis of GlyC from S-TGD-1.
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Osmotic Shock induces the presence of glycocardiolipin in the purple membrane of halobacterium salinarum
Journal of Lipid Research, 2003Co-Authors: Simona Lobasso, Veronica M T Lattanzio, Patrizia Lopalco, Angela CorcelliAbstract:In the purple membrane (PM) of Halobacterium salinarum is present a phospholipid dimer consisting of sulfo-triglycosyl-diether (S-TGD-1) esterified to the phos- phate group of phosphatidic acid (PA), i.e., S-TGD-1-PA, called glycocardiolipin (GlyC) (Corcelli, A., M. Colella, G. Mascolo, F. P. Fanizzi, and M. Kates. A novel glycolipid and phospholipid in the purple membrane. 2000. Biochemistry. 39: 3318-3326). The GlyC content of whole cells, PM, and other cell fractions of H. salinarum have been analyzed. GlyC is a nonabundant phospholipid in H. salinarum cells, and it represents one of the major phospholipids of iso- lated PM. In this report, we show that a ) GlyC is formed during the isolation of PM, b ) GlyC increase in H. salinarum cells is specifically induced by Osmotic Shock, and c ) in cor- respondence with GlyC increase, a decrease of S-TGD-1 lev- els occurs. The changes in membrane lipid composition ob- served during the isolation of PM are due to de novo synthesis of GlyC from S-TGD-1. —Lobasso S., P. Lopalco, V. M. T. Lattanzio, and A. Corcelli. Osmotic Shock induces the presence of glycocardiolipin in the purple membrane of Halobacterium salinarum . J. Lipid. Res. 2003. 44: 2120-2126.
Jeffrey E Pessin - One of the best experts on this subject based on the ideXlab platform.
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A Crk-II/TC10 signaling pathway is required for Osmotic Shock-stimulated glucose transport.
Journal of Biological Chemistry, 2002Co-Authors: Philippe Gual, Satoshi Shigematsu, Makoto Kanzaki, Thierry Grémeaux, Teresa Gonzalez, Jeffrey E Pessin, Yannick Le Marchand-brustel, Jean-françois TantiAbstract:Osmotic Shock stimulates the translocation of the glucose transporter Glut 4 to plasma membrane by a tyrosine kinase signaling pathway involving Gab-1 (the Grb2-associated binder-1 protein). We show here that, in response to Osmotic Shock, Gab-1 acts as a docking protein for phospholipase Cgamma1, the p85 subunit of the phosphoinositide 3-kinase and Crk-II. It has been shown that the adapter Crk-II is constitutively associated with C3G, a GDP to GTP exchange factor for several small GTP-binding proteins. We found that inhibition of the activity of phosphoinositide 3-kinase or phospholipase C did not prevent the stimulation of glucose transport by Osmotic Shock, whereas inactivation of Rho proteins by Clostridium difficile toxin B severely inhibited glucose uptake. Among the Rho family members, overexpression of dominant-interfering TC10/T31N mutant inhibited Osmotic Shock-mediated Glut 4 translocation suggesting that TC10 is required for this process. Further, disruption of cortical actin integrity by latrunculin B or jasplakinolide severely impaired Osmotic Shock-induced glucose transport. In contrast, Osmotic Shock increased the amount of cortical actin associated with caveolin-enriched plasma membrane domains. These data provide the first evidence that activation of TC10 and remodeling of cortical actin, which could occur through the TC10 signaling, are required for Osmotic Shock-mediated Glut 4 translocation and glucose uptake.
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Osmotic Shock inhibits insulin signaling by maintaining akt protein kinase b in an inactive dephosphorylated state
Molecular and Cellular Biology, 1999Co-Authors: Dong Chen, Ann Louise Olson, Raymond V Fucini, Brian A Hemmings, Jeffrey E PessinAbstract:We have previously reported that insulin and Osmotic Shock stimulate an increase in glucose transport activity and translocation of the insulin-responsive glucose transporter isoform GLUT4 to the plasma membrane through distinct pathways in 3T3L1 adipocytes (D. Chen, J. S. Elmendorf, A. L. Olson, X. Li, H. S. Earp, and J. E. Pessin, J. Biol. Chem. 272:27401-27410, 1997). In investigations of the relationships between these two signaling pathways, we have now observed that these two stimuli are not additive, and, in fact, Osmotic Shock pretreatment was found to completely prevent any further insulin stimulation of glucose transport activity and GLUT4 protein translocation. In addition, Osmotic Shock inhibited the insulin stimulation of lipogenesis and glycogen synthesis. This inhibition of insulin-stimulated downstream signaling occurred without any significant effect on insulin receptor autophosphorylation or tyrosine phosphorylation of insulin receptor substrate 1 (IRS1). Furthermore, there was no effect on either the insulin-stimulated association of the p85 type I phosphatidylinositol (PI) 3-kinase regulatory subunit with IRS1 or phosphotyrosine antibody-immunoprecipitated PI 3-kinase activity. In contrast, Osmotic Shock pretreatment markedly inhibited the insulin stimulation of protein kinase B (PKB) and p70S6 kinase activities. In addition, the dephosphorylation of PKB was prevented by pretreatment with the phosphatase inhibitors okadaic acid and calyculin A. These data support a model in which Osmotic Shock-induced insulin resistance of downstream biological responses results from an inhibition of insulin-stimulated PKB activation.
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Osmotic Shock stimulates glut4 translocation in 3t3l1 adipocytes by a novel tyrosine kinase pathway
Journal of Biological Chemistry, 1997Co-Authors: Dong Chen, Jeffrey S. Elmendorf, Ann Louise Olson, Shelton H Earp, Jeffrey E PessinAbstract:Similar to insulin, Osmotic Shock of 3T3L1 adipocytes stimulated an increase in glucose transport activity and translocation of GLUT4 protein from intracellularly localized vesicles to the plasma membrane. The docking/fusion of GLUT4 vesicles with the plasma membrane appeared to utilize a similar mechanism, since expression of a dominant interfering mutant of syntaxin-4 prevented both insulin- and Osmotic Shock-induced GLUT4 translocation. However, although the insulin stimulation of GLUT4 translocation and glucose transport activity was completely inhibited by wortmannin, activation by Osmotic Shock was wortmannin-insensitive. Furthermore, insulin stimulated the phosphorylation and activation of the Akt kinase, whereas Osmotic Shock was completely without effect. Surprisingly, treatment of cells with the tyrosine kinase inhibitor, genistein, or microinjection of phosphotyrosine antibody prevented both the insulin- and Osmotic Shock-stimulated translocation of GLUT4. In addition, Osmotic Shock induced the tyrosine phosphorylation of several discrete proteins including Cbl, p130(cas), and the recently identified soluble tyrosine kinase, calcium-dependent tyrosine kinase (CADTK). In contrast, insulin had no effect on CADTK but stimulated the tyrosine phosphorylation of Cbl and the tyrosine dephosphorylation of pp125(FAK) and p130(cas). These data demonstrate that the Osmotic Shock stimulation of GLUT4 translocation in adipocytes occurs through a novel tyrosine kinase pathway that is independent of both the phosphatidylinositol 3-kinase and the Akt kinase.
