Metabolic pathways for the degradation of phosphatidic acid in isolated nuclei from cerebellar cells

VL Gaveglio, SJ Pasquaré, NM Giusto - Archives of biochemistry and …, 2011 - Elsevier
VL Gaveglio, SJ Pasquaré, NM Giusto
Archives of biochemistry and biophysics, 2011Elsevier
The aim of the present research was to analyse the pathways for phosphatidic acid
metabolism in purified nuclei from cerebellar cells. Lipid phosphate phosphatase and
diacylglyceride lipase activities were detected in nuclei from cerebellar cells. It was
observed that DAGL activity makes up 50% of LPP activity and that PtdOH can also be
metabolised to lysophosphatidic acid. With a nuclear protein content of approximately 40μg,
the production of diacylglycerol and monoacylglycerol was linear for 30min and 5min …
The aim of the present research was to analyse the pathways for phosphatidic acid metabolism in purified nuclei from cerebellar cells. Lipid phosphate phosphatase and diacylglyceride lipase activities were detected in nuclei from cerebellar cells. It was observed that DAGL activity makes up 50% of LPP activity and that PtdOH can also be metabolised to lysophosphatidic acid. With a nuclear protein content of approximately 40μg, the production of diacylglycerol and monoacylglycerol was linear for 30min and 5min, respectively, whereas it increased with PtdOH concentrations of up to 250μM. LysoPtdOH, sphingosine 1-phosphate and ceramide 1-phosphate, which are alternative substrates for LPP, significantly reduced DAG production from PA. DAG and MAG production increased in the presence of Triton X-100 (1mM) whereas no modifications were observed in the presence of ionic detergent sodium deoxycholate. Ca2+ and Mg2+ stimulated MAG production without affecting DAG formation whereas fluoride and vanadate inhibited the generation of both products. Specific PtdOH-phospholipase A1 and PtdOH-phospholipase A2 were also detected in nuclei. Our findings constitute the first reported evidence of active PtdOH metabolism involving LPP, DAGL and PtdOH-selective PLA activities in purified nuclei prepared from cerebellar cells.
Elsevier