Hatten M E, Scandella C J, Horwitz A F, Burger M M
J Biol Chem. 1978 Mar 25;253(6):1972-7.
Intact, viable ultransformed 3T3 and transformed SV101-3T3 cells were labeled with fatty acid spin labels and with 2,2,6,6-tetramethylpiperidine-1-oxyl in order to measure the fluidity properties of membrane lipids. Both cell types were grown in regular calf serum and in a lipid-depleted serum supplemented with either oleate or elaidate. The temperature dependence of the spectra obtained revealed inflections that correlate with the temperature below which agglutination with concanavalin A is inhibited, and another inflection that correlates with the temperature below which agglutination with wheat germ agglutinin is inhibited, suggesting that (a) the lipid phase(s) in the vicinity of the receptor(s) for these two lectins differ, and (b) a fluid membrane in the vicinity of the lectin receptor(s) is necessary for agglutination with either concanavalin A or wheat germ agglutinin. Studies with a partially characterized plasma membrane fraction suggest that the plasma membrane fluidity parameters closely resemble those of the intact cell. 3T3 and SV101-3T3 cells show virtually identical fluidity profiles by all of the tests we have applied.
为了测量膜脂的流动性特性，将完整、有活力的未转化3T3细胞和转化的SV101 - 3T3细胞用脂肪酸自旋标记物和2,2,6,6 - 四甲基哌啶 - 1 - 氧基进行标记。两种细胞类型均在常规小牛血清以及补充了油酸或反油酸的脂质缺乏血清中培养。所获得光谱的温度依赖性显示出拐点，这些拐点与伴刀豆球蛋白A凝集被抑制的温度相关，以及另一个与麦胚凝集素凝集被抑制的温度相关的拐点，这表明：（a）这两种凝集素受体附近的脂质相不同，并且（b）凝集素受体附近的流动性膜对于伴刀豆球蛋白A或麦胚凝集素的凝集是必需的。对部分特性已明确的质膜部分的研究表明，质膜流动性参数与完整细胞的非常相似。通过我们所应用的所有测试，3T3和SV101 - 3T3细胞显示出几乎相同的流动性概况。
