Overactivation of phospholipase C-gamma1 renders platelet-derived growth factor beta-receptor-expressing cells independent of the phosphatidylinositol 3-kinase pathway for chemotaxis.

L Rönnstrand; A Siegbahn; C Rorsman; M Johnell; Klaus Hansen; C H Heldin

Overactivation of phospholipase C-gamma1 renders platelet-derived growth factor beta-receptor-expressing cells independent of the phosphatidylinositol 3-kinase pathway for chemotaxis.

L Rönnstrand, A Siegbahn, C Rorsman, M Johnell, Klaus Hansen, C H Heldin

33 Citations (Scopus)

Abstract

We have previously shown that porcine aortic endothelial cells expressing the Y934F platelet-derived growth factor (PDGF) beta-receptor mutant respond to PDGF-BB in a chemotaxis assay at about 100-fold lower concentration than do wild-type PDGF beta-receptor-expressing cells (Hansen, K., Johnell, M., Siegbahn, A. , Rorsman, C., Engström, U., Wernstedt, C., Heldin, C.-H., and Rönnstrand, L. (1996) EMBO J. 15, 5299-5313). Here we show that the increased chemotaxis correlates with increased activation of phospholipase C-gamma1 (PLC-gamma1), measured as inositol-1,4, 5-trisphosphate release. By two-dimensional phosphopeptide mapping, the increase in phosphorylation of PLC-gamma1 was shown not to be selective for any site, rather a general increase in phosphorylation of PLC-gamma1 was seen. Specific inhibitors of protein kinase C, bisindolylmaleimide (GF109203X), and phosphatidylinositol 3-kinase (PI3-kinase), LY294002, did not affect the activation of PLC-gamma1. To assess whether increased activation of PLC-gamma1 is the cause of the hyperchemotactic behavior of the Y934F mutant cell line, we constructed cell lines expressing either wild-type or a catalytically compromised version of PLC-gamma1 under a tetracycline-inducible promoter. Overexpression and concomitant increased activation of wild-type PLC-gamma1 in response to PDGF-BB led to a hyperchemotactic behavior of the cells, while the catalytically compromised PLC-gamma1 mutant had no effect on PDGF-BB-induced chemotaxis. Furthermore, in cells expressing normal levels of PLC-gamma1, chemotaxis was inhibited by LY294002. In contrast, the increase in chemotactic response seen upon overexpression of PLC-gamma1 was not inhibited by the PI3-kinase inhibitor LY294002. These observations suggest the existence of two different pathways which mediate PDGF-induced chemotaxis; depending on the cellular context, the PI3-kinase pathway or the PLC-gamma1 pathway may dominate.

Original language	English
Journal	Journal of Biological Chemistry
Volume	274
Issue number	31
Pages (from-to)	22089-94
Number of pages	5
ISSN	0021-9258
Publication status	Published - 1999

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Overactivation of phospholipase C-gamma1 renders platelet-derived growth factor beta-receptor-expressing cells independent of the phosphatidylinositol 3-kinase pathway for chemotaxis. / Rönnstrand, L; Siegbahn, A; Rorsman, C et al.
In: Journal of Biological Chemistry, Vol. 274, No. 31, 1999, p. 22089-94.

Research output: Contribution to journal › Journal article › Research › peer-review

@article{58ec7610532511dd8d9f000ea68e967b,

title = "Overactivation of phospholipase C-gamma1 renders platelet-derived growth factor beta-receptor-expressing cells independent of the phosphatidylinositol 3-kinase pathway for chemotaxis.",

abstract = "We have previously shown that porcine aortic endothelial cells expressing the Y934F platelet-derived growth factor (PDGF) beta-receptor mutant respond to PDGF-BB in a chemotaxis assay at about 100-fold lower concentration than do wild-type PDGF beta-receptor-expressing cells (Hansen, K., Johnell, M., Siegbahn, A. , Rorsman, C., Engstr{\"o}m, U., Wernstedt, C., Heldin, C.-H., and R{\"o}nnstrand, L. (1996) EMBO J. 15, 5299-5313). Here we show that the increased chemotaxis correlates with increased activation of phospholipase C-gamma1 (PLC-gamma1), measured as inositol-1,4, 5-trisphosphate release. By two-dimensional phosphopeptide mapping, the increase in phosphorylation of PLC-gamma1 was shown not to be selective for any site, rather a general increase in phosphorylation of PLC-gamma1 was seen. Specific inhibitors of protein kinase C, bisindolylmaleimide (GF109203X), and phosphatidylinositol 3-kinase (PI3-kinase), LY294002, did not affect the activation of PLC-gamma1. To assess whether increased activation of PLC-gamma1 is the cause of the hyperchemotactic behavior of the Y934F mutant cell line, we constructed cell lines expressing either wild-type or a catalytically compromised version of PLC-gamma1 under a tetracycline-inducible promoter. Overexpression and concomitant increased activation of wild-type PLC-gamma1 in response to PDGF-BB led to a hyperchemotactic behavior of the cells, while the catalytically compromised PLC-gamma1 mutant had no effect on PDGF-BB-induced chemotaxis. Furthermore, in cells expressing normal levels of PLC-gamma1, chemotaxis was inhibited by LY294002. In contrast, the increase in chemotactic response seen upon overexpression of PLC-gamma1 was not inhibited by the PI3-kinase inhibitor LY294002. These observations suggest the existence of two different pathways which mediate PDGF-induced chemotaxis; depending on the cellular context, the PI3-kinase pathway or the PLC-gamma1 pathway may dominate.",

author = "L R{\"o}nnstrand and A Siegbahn and C Rorsman and M Johnell and Klaus Hansen and Heldin, {C H}",

note = "Keywords: 1-Phosphatidylinositol 3-Kinase; Amino Acid Substitution; Animals; Cell Line; Chemotaxis; Chromones; Doxycycline; Enzyme Activation; Enzyme Inhibitors; Gene Expression Regulation, Enzymologic; Indoles; Inositol 1,4,5-Trisphosphate; Inositol Phosphates; Isoenzymes; Kinetics; Maleimides; Morpholines; Peptide Mapping; Phospholipase C gamma; Phosphorylation; Platelet-Derived Growth Factor; Point Mutation; Receptor, Platelet-Derived Growth Factor beta; Receptors, Platelet-Derived Growth Factor; Recombinant Proteins; Transfection; Type C Phospholipases",

year = "1999",

language = "English",

volume = "274",

pages = "22089--94",

journal = "Journal of Biological Chemistry",

issn = "0021-9258",

publisher = "American Society for Biochemistry and Molecular Biology, Inc.",

number = "31",

}

TY - JOUR

T1 - Overactivation of phospholipase C-gamma1 renders platelet-derived growth factor beta-receptor-expressing cells independent of the phosphatidylinositol 3-kinase pathway for chemotaxis.

AU - Rönnstrand, L

AU - Siegbahn, A

AU - Rorsman, C

AU - Johnell, M

AU - Hansen, Klaus

AU - Heldin, C H

N1 - Keywords: 1-Phosphatidylinositol 3-Kinase; Amino Acid Substitution; Animals; Cell Line; Chemotaxis; Chromones; Doxycycline; Enzyme Activation; Enzyme Inhibitors; Gene Expression Regulation, Enzymologic; Indoles; Inositol 1,4,5-Trisphosphate; Inositol Phosphates; Isoenzymes; Kinetics; Maleimides; Morpholines; Peptide Mapping; Phospholipase C gamma; Phosphorylation; Platelet-Derived Growth Factor; Point Mutation; Receptor, Platelet-Derived Growth Factor beta; Receptors, Platelet-Derived Growth Factor; Recombinant Proteins; Transfection; Type C Phospholipases

PY - 1999

Y1 - 1999

N2 - We have previously shown that porcine aortic endothelial cells expressing the Y934F platelet-derived growth factor (PDGF) beta-receptor mutant respond to PDGF-BB in a chemotaxis assay at about 100-fold lower concentration than do wild-type PDGF beta-receptor-expressing cells (Hansen, K., Johnell, M., Siegbahn, A. , Rorsman, C., Engström, U., Wernstedt, C., Heldin, C.-H., and Rönnstrand, L. (1996) EMBO J. 15, 5299-5313). Here we show that the increased chemotaxis correlates with increased activation of phospholipase C-gamma1 (PLC-gamma1), measured as inositol-1,4, 5-trisphosphate release. By two-dimensional phosphopeptide mapping, the increase in phosphorylation of PLC-gamma1 was shown not to be selective for any site, rather a general increase in phosphorylation of PLC-gamma1 was seen. Specific inhibitors of protein kinase C, bisindolylmaleimide (GF109203X), and phosphatidylinositol 3-kinase (PI3-kinase), LY294002, did not affect the activation of PLC-gamma1. To assess whether increased activation of PLC-gamma1 is the cause of the hyperchemotactic behavior of the Y934F mutant cell line, we constructed cell lines expressing either wild-type or a catalytically compromised version of PLC-gamma1 under a tetracycline-inducible promoter. Overexpression and concomitant increased activation of wild-type PLC-gamma1 in response to PDGF-BB led to a hyperchemotactic behavior of the cells, while the catalytically compromised PLC-gamma1 mutant had no effect on PDGF-BB-induced chemotaxis. Furthermore, in cells expressing normal levels of PLC-gamma1, chemotaxis was inhibited by LY294002. In contrast, the increase in chemotactic response seen upon overexpression of PLC-gamma1 was not inhibited by the PI3-kinase inhibitor LY294002. These observations suggest the existence of two different pathways which mediate PDGF-induced chemotaxis; depending on the cellular context, the PI3-kinase pathway or the PLC-gamma1 pathway may dominate.

AB - We have previously shown that porcine aortic endothelial cells expressing the Y934F platelet-derived growth factor (PDGF) beta-receptor mutant respond to PDGF-BB in a chemotaxis assay at about 100-fold lower concentration than do wild-type PDGF beta-receptor-expressing cells (Hansen, K., Johnell, M., Siegbahn, A. , Rorsman, C., Engström, U., Wernstedt, C., Heldin, C.-H., and Rönnstrand, L. (1996) EMBO J. 15, 5299-5313). Here we show that the increased chemotaxis correlates with increased activation of phospholipase C-gamma1 (PLC-gamma1), measured as inositol-1,4, 5-trisphosphate release. By two-dimensional phosphopeptide mapping, the increase in phosphorylation of PLC-gamma1 was shown not to be selective for any site, rather a general increase in phosphorylation of PLC-gamma1 was seen. Specific inhibitors of protein kinase C, bisindolylmaleimide (GF109203X), and phosphatidylinositol 3-kinase (PI3-kinase), LY294002, did not affect the activation of PLC-gamma1. To assess whether increased activation of PLC-gamma1 is the cause of the hyperchemotactic behavior of the Y934F mutant cell line, we constructed cell lines expressing either wild-type or a catalytically compromised version of PLC-gamma1 under a tetracycline-inducible promoter. Overexpression and concomitant increased activation of wild-type PLC-gamma1 in response to PDGF-BB led to a hyperchemotactic behavior of the cells, while the catalytically compromised PLC-gamma1 mutant had no effect on PDGF-BB-induced chemotaxis. Furthermore, in cells expressing normal levels of PLC-gamma1, chemotaxis was inhibited by LY294002. In contrast, the increase in chemotactic response seen upon overexpression of PLC-gamma1 was not inhibited by the PI3-kinase inhibitor LY294002. These observations suggest the existence of two different pathways which mediate PDGF-induced chemotaxis; depending on the cellular context, the PI3-kinase pathway or the PLC-gamma1 pathway may dominate.

M3 - Journal article

C2 - 10419537

SN - 0021-9258

VL - 274

SP - 22089

EP - 22094

JO - Journal of Biological Chemistry

JF - Journal of Biological Chemistry

IS - 31

ER -

Overactivation of phospholipase C-gamma1 renders platelet-derived growth factor beta-receptor-expressing cells independent of the phosphatidylinositol 3-kinase pathway for chemotaxis.

Abstract

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