Tsao F H
Lipids. 1986 Aug;21(8):498-502. doi: 10.1007/BF02535636.
The effect of cytidine 5'-monophosphate (CMP) on the incorporation of cytidine 5'-diphosphate (CDP) [methyl-14C]choline or [1-14C]dipalmitoylglycerol into phosphatidylcholine (PC) catalyzed by rabbit lung microsomal CDPcholine:1,2-diacyl-sn-glycerol cholinephosphotransferase (EC 2.7.8.2) was studied. In the presence of 0.85 mM CMP and nonsaturating diacylglycerol concentration, the incorporation of CDP[14C]choline into PC was markedly stimulated, but the incorporation of [14C]dipalmitoylglycerol into PC was inhibited. This was due to the increase of endogenous diacylglycerol generated from microsomal PC by the cholinephosphotransferase reverse reaction. However, the newly synthesized PC was not readily hydrolyzed in the presence of CMP. The results of this study suggest that the endogenous membranous diacylglycerol is utilized more preferentially for PC synthesis than the exogenous diacylglycerol and that the newly synthesized PC could rapidly equilibrate with the endogenous membrane PC pool.
研究了胞苷5'-单磷酸（CMP）对兔肺微粒体CDP胆碱：1,2-二酰基-sn-甘油胆碱磷酸转移酶（EC 2.7.8.2）催化的胞苷5'-二磷酸（CDP）[甲基-14C]胆碱或[1-14C]二棕榈酰甘油掺入磷脂酰胆碱（PC）的影响。在存在0.85 mM CMP和非饱和二酰甘油浓度的情况下，CDP[14C]胆碱掺入PC的过程受到显著刺激，但[14C]二棕榈酰甘油掺入PC的过程受到抑制。这是由于胆碱磷酸转移酶的逆反应使微粒体PC产生的内源性二酰甘油增加所致。然而，在CMP存在的情况下，新合成的PC不易被水解。本研究结果表明，内源性膜二酰甘油比外源性二酰甘油更优先用于PC合成，并且新合成的PC可以迅速与内源性膜PC池达到平衡。
