Gemeinhardt Anja, Alfalah Marwan, Gück Thomas, Naim Hassan Y, Fuhrmann Herbert
Institute of Biochemistry, Faculty of Veterinary Medicine, University of Leipzig, An den Tierkliniken 1, D-04103 Leipzig, Germany.
Biol Chem. 2009 Mar;390(3):253-8. doi: 10.1515/BC.2009.024.
Phospholipase D (PLD) is a receptor-regulated signalling enzyme involved in biological functions, such as exocytosis, phagocytosis, actin dynamics, membrane trafficking, and is considered to be essential for stimulated degranulation of cells. The purpose of our investigation was to examine how the fatty acid pattern of cellular membranes influences the activities and cellular distribution of the PLD1 and PLD2 isoforms. Expression of GFP-tagged PLD1 and PLD2 in COS-1 cells that were stimulated with mastoparan after cultivation in 20 micromol linoleic (C18:2n6) or linolenic (C18:3n3) acid for 4 d demonstrated that PLD1 dramatically alters its cellular distribution and is redistributed from intracellular vesicles to the cell surface. PLD2, on the other hand, maintains its localisation at the plasma membrane. The activity of PLD, which corresponds to PLD1 and PLD2, significantly increased two- to three-fold in the presence of the fatty acids. We conclude that linoleic acid and linolenic acid supplementation affect the intracellular trafficking of the PLD1 isoform and the activity of PLD most likely due to alterations in the membrane lipid environment conferred by the fatty acids.
磷脂酶D（PLD）是一种受受体调节的信号酶，参与诸如胞吐作用、吞噬作用、肌动蛋白动力学、膜运输等生物学功能，并且被认为是细胞刺激脱颗粒所必需的。我们研究的目的是考察细胞膜的脂肪酸模式如何影响PLD1和PLD2亚型的活性及细胞分布。在用20微摩尔亚油酸（C18:2n6）或亚麻酸（C18:3n3）培养4天后，用马斯托帕兰刺激的COS-1细胞中，绿色荧光蛋白标记的PLD1和PLD2的表达表明，PLD1显著改变其细胞分布，从细胞内囊泡重新分布到细胞表面。另一方面，PLD2维持其在质膜上的定位。与PLD1和PLD2相对应的PLD活性在脂肪酸存在的情况下显著增加了两到三倍。我们得出结论，补充亚油酸和亚麻酸会影响PLD1亚型的细胞内运输以及PLD的活性，这很可能是由于脂肪酸赋予的膜脂环境改变所致。
