Effect of membrane phosphatidylethanolamine-deficiency/phosphatidylcholine-excess on the metabolism of phosphatidylcholine and phosphatidylethanolamine.
Effect of membrane phosphatidylethanolamine-deficiency/phosphatidylcholine-excess on the metabolism of phosphatidylcholine and phosphatidylethanolamine.
复制标题
膜磷脂酰乙醇胺缺乏/磷脂酰胆碱过量对磷脂酰胆碱和磷脂酰乙醇胺代谢的影响。
DOI：
10.1002/jcp.1041530321
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发表时间：
1992
影响因子：
5.6
通讯作者：
Kano-Sueoka,T
中科院分区：
文献类型：
--
作者：
Fisk,HA;Kano-Sueoka,T
上皮来源的细胞通常需要乙醇胺(ETN)才能在特定的培养基中生长。当这类细胞在没有ETN的情况下生长时，细胞膜的磷脂组成发生了巨大的变化，由于磷脂酰乙醇胺(PE)合成的从头合成速度降低，导致PE缺乏，生长停止。我们假设生长停止是因为这种膜磷脂环境不再适合膜相关功能。长期以来，磷脂在一些信号跨膜传递中扮演着重要角色。除了众所周知的磷脂酰肌醇循环，磷脂酰胆碱(PC)和PE的水解最近被证明在信号转导中发挥核心作用。利用需要内毒素的大鼠乳腺细胞系-24，我们研究了在细胞膜磷脂正常或缺乏膜磷脂的情况下，佛波酯佛波酯对PC和PE代谢的影响。在膜磷脂正常的细胞中，PDBu刺激PC的合成(∼4倍)，PC和PE的降解(分别为2倍和4倍)。产物分析表明，PDBu促进磷脂酶C和D(PLC和PLD)对PC和PLD对PE的水解。然而，在PE缺乏的细胞中，PDBu对脂质的合成和降解都没有明显的刺激作用。对PC合成的CDP-胆碱途径的分析表明，在膜正常的细胞中，PDBu可使调节酶CTP：磷脂酰胆碱胞苷转移酶激活约一倍，而在PE缺乏的细胞中则不能。这些结果表明，膜磷脂环境深刻地影响磷脂代谢，而磷脂代谢无疑影响细胞的生长和调节。©1992 Wiley-Liss，Inc.
Cells of epithelial origin generally require ethanolamine (Etn) to grow in defined culture medium. When such cells are grown without Etn, the membrane phospholipid composition changes drastically, becoming phosphatidylethanolamine (PE)‐deficient due to a reduced de novo rate of PE synthesis, and growth stops. We have hypothesized that the cessation of growth occurs because this membrane phospholipid environment is no longer suitable for membrane‐associated functions. Phospholipid has long been known to play a role in the transduction of some signals across membranes. In addition to the well‐known phosphatidylinositol cycles, hydrolysis of phosphatidylcholine (PC) and PE has recently been shown to play a central role in signal transduction. Using an Etn‐requiring rat mammary cell line 64‐24, we have studied the metabolism of PC and PE in response to the phorbol ester phorbol 12, 13‐dibutyrate (PDBu) under conditions where cells have either normal or PE‐deficient membrane phospholipid. In cells having normal membrane phospholipid, the synthesis of PC was stimulated by PDBu (∼fourfold), as was the degradation of PC and PE (by twofold and fourfold, respectively). Product analysis suggested that PDBu stimulated hydrolysis of PC by both phospholipases C and D (PLC and PLD), and of PE by PLD. However, in PE‐deficient cells, neither lipid synthesis or degradation were significantly stimulated by PDBu. Analysis of the CDP‐choline pathway of PC sythesis indicated that the regulatory enzyme, CTP: phosphorylcholine cytidylyltransferase, was stimulated about twofold by PDBu in cells having normal membrane, but not in PE‐deficient cells. These results indicate that the membrane phospholipid environment profoundly affects phospholipid metabolism, which no doubt influences cell growth and regulation. © 1992 Wiley‐Liss, Inc.