scholarly journals CaM kinase IIalpha mediates norepinephrine-induced translocation of cytosolic phospholipase A2 to the nuclear envelope

2002 ◽  
Vol 116 (2) ◽  
pp. 353-365 ◽  
Author(s):  
S. Fatima
Keyword(s):  
Nuclear Envelope ◽  
Phospholipase A2 ◽  
Cytosolic Phospholipase A2 ◽  
Cam Kinase ◽  
Cytosolic Phospholipase

scholarly journals Role of Phosphorylation Sites and the C2 Domain in Regulation of Cytosolic Phospholipase A2

1999 ◽  
Vol 145 (6) ◽  
pp. 1219-1232 ◽  
Author(s):  
Miguel A. Gijón ◽  
Diane M. Spencer ◽  
Alan L. Kaiser ◽  
Christina C. Leslie
Keyword(s):  
Arachidonic Acid ◽  
Nuclear Envelope ◽  
Phospholipase A2 ◽  
Okadaic Acid ◽  
Cytosolic Phospholipase A2 ◽  
Phosphorylation Sites ◽  
C2 Domain ◽  
Arachidonic Acid Release ◽  
Cytosolic Phospholipase ◽  
Acid Release

Cytosolic phospholipase A2 (cPLA2) mediates agonist-induced arachidonic acid release, the first step in eicosanoid production. cPLA2 is regulated by phosphorylation and by calcium, which binds to a C2 domain and induces its translocation to membrane. The functional roles of phosphorylation sites and the C2 domain of cPLA2 were investigated. In Sf9 insect cells expressing cPLA2, okadaic acid, and the calcium-mobilizing agonists A23187 and CryIC toxin induce arachidonic acid release and translocation of green fluorescent protein (GFP)-cPLA2 to the nuclear envelope. cPLA2 is phosphorylated on multiple sites in Sf9 cells; however, only S505 phosphorylation partially contributes to cPLA2 activation. Although okadaic acid does not increase calcium, mutating the calcium-binding residues D43 and D93 prevents arachidonic acid release and translocation of cPLA2, demonstrating the requirement for a functional C2 domain. However, the D93N mutant is fully functional with A23187, whereas the D43N mutant is nearly inactive. The C2 domain of cPLA2 linked to GFP translocates to the nuclear envelope with calcium-mobilizing agonists but not with okadaic acid. Consequently, the C2 domain is necessary and sufficient for translocation of cPLA2 to the nuclear envelope when calcium is increased; however, it is required but not sufficient with okadaic acid.

scholarly journals Translocation of cytosolic phospholipase A2 to the nuclear envelope elicits topographically localized phospholipid hydrolysis

1996 ◽  
Vol 318 (3) ◽  
pp. 797-803 ◽  
Author(s):  
Marc PETERS-GOLDEN ◽  
Keli SONG ◽  
Teresa MARSHALL ◽  
Thomas BROCK
Keyword(s):  
Nuclear Envelope ◽  
Phospholipase A2 ◽  
Nuclear Membrane ◽  
Microscopic Analysis ◽  
Cytosolic Phospholipase A2 ◽  
Alveolar Epithelial Cells ◽  
Ionophore A23187 ◽  
Membrane Phospholipids ◽  
Phospholipid Hydrolysis ◽  
Cytosolic Phospholipase

Cytosolic phospholipase A2 (cPLA2) is a good candidate for mediating the agonist-stimulated release of arachidonic acid (AA) from membrane phospholipids. This enzyme undergoes a Ca2+-dependent translocation from the cytosol to a membrane site in a variety of cell types, and this site has recently been identified as the nuclear envelope in leucocytes. The functional correlate of this finding has not yet been established. The present study was therefore undertaken to determine whether translocation of cPLA2 to the nuclear envelope was associated with localized phospholipid hydrolysis at this site. Rat alveolar epithelial cells, previously shown to contain cPLA2, were prelabelled with [3H]AA and stimulated with the model agonist, ionophore A23187. Ionophore-induced AA release exhibited characteristics typical of a cPLA2-mediated response, in that it was Ca2+-dependent, sn-2 AA-selective, and inhibited by arachidonyl trifluoromethyl ketone. As determined by indirect immunofluorescence microscopic analysis as well as subcellular fractionation with immunoblotting, ionophore treatment resulted in a translocation of cPLA2 protein from the cytoplasm to the nuclear envelope. To determine whether the nuclear membrane was indeed the source of released AA, prelabelled cells were incubated in the presence or absence of A23187, after which the phospholipid radioactivity was quantified in nuclear and non-nuclear membrane fractions. [3H]AA was distributed in both nuclear and non-nuclear membrane phospholipids. Following A23187 stimulation, the loss of [3H]AA from nuclear membrane phospholipids accounted for 88.1±5.8% of the total loss from phospholipids and for 92.9±2.3% of the total [3H]AA released into the medium. These results demonstrate for the first time that agonist-stimulated translocation of cPLA2 to the nuclear envelope is associated with phospholipid hydrolysis which is preferentially localized to that site.

scholarly journals Modulation of cytosolic phospholipase A2 by PPAR activators in human preadipocytes

2001 ◽  
Vol 42 (5) ◽  
pp. 716-724
Author(s):  
Yan J. Jiang ◽  
Grant M. Hatch ◽  
David Mymin ◽  
Thomas Dembinski ◽  
Edwin A. Kroeger ◽  
...  
Keyword(s):  
Phospholipase A2 ◽  
Cytosolic Phospholipase A2 ◽  
Cytosolic Phospholipase ◽  
Human Preadipocytes

scholarly journals Molecular cloning and expression of human Ca(2+)-sensitive cytosolic phospholipase A2

1991 ◽  
Vol 266 (23) ◽  
pp. 14850-14853 ◽  
Author(s):  
J.D. Sharp ◽  
D.L. White ◽  
X.G. Chiou ◽  
T. Goodson ◽  
G.C. Gamboa ◽  
...  
Keyword(s):  
Phospholipase A2 ◽  
Molecular Cloning ◽  
Cytosolic Phospholipase A2 ◽  
Cloning And Expression ◽  
Cytosolic Phospholipase

scholarly journals A Phospholipid Substrate Molecule Residing in the Membrane Surface Mediates Opening of the Lid Region in Group IVA Cytosolic Phospholipase A2

2008 ◽  
Vol 283 (45) ◽  
pp. 31227-31236 ◽  
Author(s):  
John E. Burke ◽  
Yuan-Hao Hsu ◽  
Raymond A. Deems ◽  
Sheng Li ◽  
Virgil L. Woods ◽  
...  
Keyword(s):  
Phospholipase A2 ◽  
Membrane Surface ◽  
Cytosolic Phospholipase A2 ◽  
Substrate Molecule ◽  
Cytosolic Phospholipase ◽  
Group Iva

Implication of cytosolic phospholipase A2 in the control of osteoclast metabolism

Bone ◽  
2008 ◽  
Vol 43 ◽  
pp. S45
Author(s):  
Hugues Allard-Chamard ◽  
Artur José de Brum Fernandes
Keyword(s):  
Phospholipase A2 ◽  
Cytosolic Phospholipase A2 ◽  
Cytosolic Phospholipase
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