Long, Jaclyn and Darroch, Peter and Wan, Kah Fei and Kong, Kok Choi and Ktistakis, Nicholas and Pyne, Nigel J and Pyne, Susan (2005) Regulation of cell survival by lipid phosphate phosphatases involves the modulation of intracellular phosphatidic acid and sphingosine 1-phosphate pools. Biochemical Journal, 391 (1). pp. 25-32.Full text not available in this repository. (Request a copy from the Strathclyde author)
We have shown previously that LPPs (lipid phosphate phosphatases) reduce the stimulation of the p42/p44 MAPK (p42/p44 mitogen-activated protein kinase) pathway by the GPCR (G-protein-coupled receptor) agonists S1P (sphingosine 1-phosphate) and LPA (lysophosphatidic acid) in serum-deprived HEK-293 cells [Alderton, Darroch, Sambi, McKie, Ahmed, N. J. Pyne and S. Pyne (2001) J. Biol. Chem. 276, 13452-13460]. In the present study, we now show that this can be blocked by pretreating HEK-293 cells with the caspase 3/7 inhibitor, Ac-DEVD-CHO [N-acetyl-Asp-Glu-Val-Asp-CHO (aldehyde)]. Therefore LPP2 and LPP3 appear to regulate the apoptotic status of serum-deprived HEK-293 cells. This was supported further by: (i) caspase 3/7-catalysed cleavage of PARP [poly(ADP-ribose) polymerase] was increased in serum-deprived LPP2-overexpressing compared with vector-transfected HEK-293 cells; and (ii) serum-deprived LPP2- and LPP3-overexpressing cells exhibited limited intranucleosomal DNA laddering, which was absent in vector-transfected cells. Moreover, LPP2 reduced basal intracellular phosphatidic acid levels, whereas LPP3 decreased intracellular S1P in serum-deprived HEK-293 cells. LPP2 and LPP3 are constitutively co-localized with SK1 (sphingosine kinase 1) in cytoplasmic vesicles in HEK-293 cells. Moreover, LPP2 but not LPP3 prevents SK1 from being recruited to a perinuclear compartment upon induction of PLD1 (phospholipase D1) in CHO (Chinese-hamster ovary) cells. Taken together, these data are consistent with an important role for LPP2 and LPP3 in regulating an intracellular pool of PA and S1P respectively, that may govern the apoptotic status of the cell upon serum deprivation.
|Keywords:||animals, apoptosis, CHO cells, caspase 3, caspase 7, caspases, cell line, cell survival, cricetinae, cricetulus, enzyme activation, humans, lysophospholipids, mitogen-activated protein kinase 1, mitogen-activated protein kinase 3, phosphatidate phosphatase, phosphatidic acids, sphingosine, Pharmacy and materia medica, Biochemistry, Cell Biology, Molecular Biology|
|Subjects:||Medicine > Pharmacy and materia medica|
|Department:||Faculty of Science > Strathclyde Institute of Pharmacy and Biomedical Sciences|
|Depositing user:||Pure Administrator|
|Date Deposited:||11 Nov 2011 16:32|
|Last modified:||27 Apr 2016 17:43|