PMA Stimulated Hydrolysis of Phosphatidylcholine in CRBH7919 Cell and Its Enzymatic Basis.
The effect of phorbol 12-myristate-13-acetate (PMA) on the hydrolysis of phosphatidylcholine (PC) in rat hepatoma cell line CRBH7919 has been studied. It was found that PMA stimulated PC hydrolysis in CRBH7919 cells in a dose-dependent manner after treatment for 15 min. The product of PC hydrolysis was choline, not phosphocholine. The activity of the membrane bound PC-specific phospholipase D (PC-PLD) was determined. The results showed that the activity of PC-PLD increased after 10 min with 100 nM PMA treatment, and reached a level 3.25 times the control after 30 min. The fact that the PC-PLD activation preceded the hydrolysis of PC, suggests that PC-PLD is involved in the PC hydrolysis into phosphatidic acid and choline in CRBH7919 cells in the presence of PMA.
Zhu
Quan-Sheng
QS
Department of Biochemistry, Key Laboratory of Glycoconjugate Research, Shanghai Medical University, Shanghai 200032, China.
Zha
Xi-Liang
XL