Molecular selectivity of phospholipase D in granulocyte function
Molecular selectivity of phospholipase D in granulocyte function
HL60 cells cultured in 10% fetal calf serum (FCS)-supplemented medium were induced to differentiate to the granulocyte phenotype with 1μM retinoic acid. The molecular species compositions of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) from LH60 granulocytes were analysed by HPLC. Control HL60 granulocyte PC and PE had characteristic molecular species compositions with PC containing mostly saturated and monounsaturated species and PE containing more unsaturated species. Comparison of PC and PE species compositions of unstimulated HL60 granulocytes with the composition of P[3H]But synthesised in response to 100nM PMA showed that the P[3H]But formed resembled PC more than PE. However, the P[3H]But composition was not identical to PC with negligible formation of P[3H]But16:0/16:0. Supplementation of the cell culture medium with 30μM 18:2n-6 or 20:4n-6 fatty acid-albumin mixtures dramatically altered PC and PE molecular species compositions with significant increases in PC molecular species containing the supplemented fatty acid. Stimulation of 18:2n-6 or 20:4n-6 supplemented cells with PMA resulted in the production of mostly unsaturated P[3H]But species which were major components of the PC.
The results of this study outline the modifications to the PLD activation products caused by culture of the cells in the presence of exogenous fatty acids and demonstrate that unsaturated species can be produced by PLD when they become available in the PC composition. The results suggest that PLD acted either on a discrete pool of substrate PC separate from the bulk of cellular PC or it exhibited a degree of selectivity for certain molecular species of the substrate PC. It is possible that modulation of the activity and selectivity of PLD can lead to generation of PA/DAG with altered compositions and consequent altered characteristics of PKC activation. This may be one mechanism underlying the dietary-induced changes which can occur in granulocyte responses.
University of Southampton
1997
Heung, Yen Ming Mary
(1997)
Molecular selectivity of phospholipase D in granulocyte function.
University of Southampton, Doctoral Thesis.
Record type:
Thesis
(Doctoral)
Abstract
HL60 cells cultured in 10% fetal calf serum (FCS)-supplemented medium were induced to differentiate to the granulocyte phenotype with 1μM retinoic acid. The molecular species compositions of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) from LH60 granulocytes were analysed by HPLC. Control HL60 granulocyte PC and PE had characteristic molecular species compositions with PC containing mostly saturated and monounsaturated species and PE containing more unsaturated species. Comparison of PC and PE species compositions of unstimulated HL60 granulocytes with the composition of P[3H]But synthesised in response to 100nM PMA showed that the P[3H]But formed resembled PC more than PE. However, the P[3H]But composition was not identical to PC with negligible formation of P[3H]But16:0/16:0. Supplementation of the cell culture medium with 30μM 18:2n-6 or 20:4n-6 fatty acid-albumin mixtures dramatically altered PC and PE molecular species compositions with significant increases in PC molecular species containing the supplemented fatty acid. Stimulation of 18:2n-6 or 20:4n-6 supplemented cells with PMA resulted in the production of mostly unsaturated P[3H]But species which were major components of the PC.
The results of this study outline the modifications to the PLD activation products caused by culture of the cells in the presence of exogenous fatty acids and demonstrate that unsaturated species can be produced by PLD when they become available in the PC composition. The results suggest that PLD acted either on a discrete pool of substrate PC separate from the bulk of cellular PC or it exhibited a degree of selectivity for certain molecular species of the substrate PC. It is possible that modulation of the activity and selectivity of PLD can lead to generation of PA/DAG with altered compositions and consequent altered characteristics of PKC activation. This may be one mechanism underlying the dietary-induced changes which can occur in granulocyte responses.
This record has no associated files available for download.
More information
Published date: 1997
Identifiers
Local EPrints ID: 463179
URI: http://eprints.soton.ac.uk/id/eprint/463179
PURE UUID: a45fd018-45d1-4214-8d38-2c9c37f57615
Catalogue record
Date deposited: 04 Jul 2022 20:47
Last modified: 04 Jul 2022 20:47
Export record
Contributors
Author:
Yen Ming Mary Heung
Download statistics
Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.
View more statistics