Hoover R L, Fujiwara K, Klausner R D, Bhalla D K, Tucker R, Karnovsky M J
Mol Cell Biol. 1981 Oct;1(10):939-48. doi: 10.1128/mcb.1.10.939-948.1981.
Treatment of mouse lymphocytes with cis-unsaturated free fatty acids produced alterations in the immunofluorescence patterns of the cytoskeleton and contractile proteins. Saturated free fatty acids and trans-unsaturated free fatty acids had no effect. In untreated cells, the microtubular pattern exhibited radiation from an organizing center, resembling the spokes of an umbrella. The addition of linoleic acid produced a polarized submembranous aggregate. Under control conditions, staining for actin revealed a diffuse pattern over the entire cell, but the addition of linoleic acid caused the formation of a single large patch, or polarized submembranous aggregate. The pattern for alpha-actinin normally revealed intense perinuclear staining on a diffuse background. Linoleic acid caused the loss of this pattern and the formation of a polarized submembranous aggregate. Linoleic acid treatment also caused the pattern for myosin to change from diffuse to uniform submembranous patching around the periphery of the cell. For all of these proteins, calcium (8 mM), but not magnesium, partially reversed the effects of linoleic acid. Sodium azide had little effect on the normal distribution of actin, tubulin, and alpha-actinin; however, myosin staining revealed prominent patch formation. Colchicine treatment caused diffuse staining, some polarized submembranous aggregate formation of tubulin, and some patching of myosin, but not as extensively as did treatment with linoleic acid. Actin and alpha-actinin were unaffected. These results, in view of the previously shown facts that pretreatment of cells with linoleic acid followed by anti-immunoglobulin inhibits capping of surface immunoglobulin (Klausner, et al., Proc. Natl. Acad. Sci. U.S.A. 77:437-441, 1980) and that free fatty acids partition into the surface membrane (Klausner et al., J. Biol. Chem. 255:1286-1295, 1980), suggest that the perturbation of the plasma membrane with unsaturated free fatty acids alters the interaction of surface receptors with the cytoskeleton, which in turn affects cytoplasmic distribution of the proteins.
用顺式不饱和游离脂肪酸处理小鼠淋巴细胞会导致细胞骨架和收缩蛋白的免疫荧光模式发生改变。饱和游离脂肪酸和反式不饱和游离脂肪酸则没有这种作用。在未处理的细胞中，微管模式呈现出从一个组织中心发出的辐射状，类似于伞的辐条。添加亚油酸会产生一个极化的膜下聚集体。在对照条件下，肌动蛋白染色显示在整个细胞上呈弥散模式，但添加亚油酸会导致形成单个大斑块或极化的膜下聚集体。α - 辅肌动蛋白的模式通常在弥散背景上显示强烈的核周染色。亚油酸导致这种模式消失并形成极化的膜下聚集体。亚油酸处理还使肌球蛋白的模式从弥散变为细胞周边均匀的膜下斑块状。对于所有这些蛋白质，钙（8 mM）而非镁能部分逆转亚油酸的作用。叠氮化钠对肌动蛋白、微管蛋白和α - 辅肌动蛋白的正常分布影响很小；然而，肌球蛋白染色显示有明显的斑块形成。秋水仙碱处理导致弥散染色，微管蛋白有一些极化的膜下聚集体形成，肌球蛋白有一些斑块形成，但不如亚油酸处理广泛。肌动蛋白和α - 辅肌动蛋白不受影响。鉴于先前已表明的事实，即先用亚油酸预处理细胞然后用抗免疫球蛋白处理会抑制表面免疫球蛋白的帽化（克劳斯纳等人，《美国国家科学院院刊》77:437 - 441, 1980）以及游离脂肪酸会分配到表面膜中（克劳斯纳等人，《生物化学杂志》255:1286 - 1295, 1980），这些结果表明不饱和游离脂肪酸对质膜的扰动会改变表面受体与细胞骨架的相互作用，进而影响蛋白质在细胞质中的分布。
