Profiling membrane lipids in plant stress responses -: Role of phospholipase Dα in freezing-induced lipid changes in Arabidopsis
Profiling membrane lipids in plant stress responses -: Role of phospholipase Dα in freezing-induced lipid changes in Arabidopsis
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DOI：
10.1074/jbc.m205375200
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发表时间：
2002-08-30
影响因子：
4.8
通讯作者：
Wang, XM
中科院分区：
文献类型：
--
作者：
Welti, R;Li, WQ;Wang, XM
采用基于电喷雾电离串联质谱的灵敏方法分析了低温和冷冻胁迫下拟南芥的膜脂分子种类。在亚致死温度下冷冻导致许多分子种类的磷脂酰胆碱（PC）、磷脂酰乙醇胺（PE）和磷脂酰甘油（PG）的减少，但诱导磷脂酸（PA）和溶血磷脂的增加。为了探究产生这些变化的代谢步骤，我们分析了缺乏最丰富的磷脂酶D （PLDalpha）的拟南芥的脂质。缺乏pldalpa的植株中PC含量下降的幅度只有野生型植株的一半，PA含量上升的幅度只有野生型植株的一半。相比之下，与缺乏plda的植株相比，野生型植株的PE和PG水平都没有显著下降。这些数据表明，PC，而不是PE和PG，是PLDalpha在体内的主要底物。PLDalpha在冷冻过程中的作用是特别有趣的，因为缺乏PLDalpha的拟南芥植物对冷冻的耐受性更好。与缺乏pldalpha的植物相比，野生型植物中PC的损失更大，PA的增加可能是破坏膜双层结构的原因，导致野生型植物更倾向于膜融合和细胞死亡。
A sensitive approach based on electrospray ionization tandem mass spectrometry has been employed to profile membrane lipid molecular species in Arabidopsis undergoing cold and freezing stresses. Freezing at a sublethal temperature induced a decline in many molecular species of phosphatidylcholine (PC), phosphatidylethanolamine (PE), and phosphatidylglycerol (PG) but induced an increase in phosphatidic acid (PA) and lysophospholipids. To probe the metabolic steps generating these changes, lipids of Arabidopsis deficient in the most abundant phospholipase D, PLDalpha, were analyzed. The PC content dropped only half as much, and PA levels rose only half as high in the PLDalpha-deficient plants as in wild-type plants. In contrast, neither PE nor PG levels decreased significantly more in wild-type plants than in PLDa-deficient plants. These data suggest that PC, rather than PE and PG, is the major in vivo substrate of PLDalpha The action of PLDalpha during freezing is of special interest because Arabidopsis plants that are deficient in PLDalpha have improved tolerance to freezing. The greater loss of PC and increase in PA in wild-type plants as compared with PLDalpha-deficient plants may be responsible for destabilizing membrane bilayer structure, resulting in a greater propensity toward membrane fusion and cell death in wild-type plants.