Simon I, Mathur S N, Lokesh B R, Spector A A
Biochim Biophys Acta. 1984 Jun 19;804(2):245-52. doi: 10.1016/0167-4889(84)90156-3.
The fatty acid composition of cultured Friend erythroleukemia cells was modified by supplementation of the medium with oleic or linoleic acid. There was a 30% reduction in saturated and a 35% reduction in polyunsaturated fatty acids in microsomal phospholipids when the cells were grown in media supplemented with oleic acid, and a 3-fold increase in polyunsaturated fatty acids when the cells were grown in linoleic acid-supplemented media. Electron-spin resonance studies with the 5- nitroxystearate probe demonstrated that there was no appreciable change in microsomal lipid mobility as measured by the order parameters. In contrast, changes in lipid mobility were detected with the spin-label probe when microsomes were first isolated from Friend erythroleukemia cells and subsequently modified by incubation with liposomes composed of either dioleoyl- or dilinoleoylphosphatidylcholine plus bovine liver phospholipid-exchange protein. The fatty acid compositional changes produced in these microsomes were similar to those obtained when the intact cells were grown in media containing supplemental fatty acids. These findings indicate that the lipid mobility of Friend cell microsomes can be altered by phospholipid replacements in vitro, but that this does not occur when similar microsomal fatty acid modifications are produced during culture of the intact cell.
通过在培养基中添加油酸或亚油酸来改变培养的弗氏红白血病细胞的脂肪酸组成。当细胞在添加油酸的培养基中生长时，微粒体磷脂中的饱和脂肪酸减少30%，多不饱和脂肪酸减少35%；而当细胞在添加亚油酸的培养基中生长时，多不饱和脂肪酸增加3倍。用5-硝基硬脂酸盐探针进行的电子自旋共振研究表明，通过序参数测量，微粒体脂质流动性没有明显变化。相比之下，当首先从弗氏红白血病细胞中分离出微粒体，然后与由二油酰磷脂酰胆碱或二亚油酰磷脂酰胆碱加牛肝磷脂交换蛋白组成的脂质体一起孵育进行修饰时，用自旋标记探针检测到脂质流动性发生了变化。这些微粒体中产生的脂肪酸组成变化与完整细胞在含有补充脂肪酸的培养基中生长时获得的变化相似。这些发现表明，弗氏细胞微粒体的脂质流动性可以通过体外磷脂替代来改变，但在完整细胞培养过程中产生类似的微粒体脂肪酸修饰时，这种情况不会发生。
