Gilula N B, Eger R R, Rifkin D B
Proc Natl Acad Sci U S A. 1975 Sep;72(9):3594-8. doi: 10.1073/pnas.72.9.3594.
The intramembrane organization of the plasma membranes of nonmalignant cells in culture has been compared by freeze-fracturing with that of virally-transformed malignant cells. No dramatic differences are present in the distribution of intramembrane particles in the plasma membranes of these cells when the cells are examined without fixation or with mild fixation (glutaraldehyde treatment) prior to freezing. However, a redistribution of intramembrane particles into aggregates occurs in the membranes of nontransformed cells after treatment with glycerol. The aggregation of particles is extensive in normal chick embryo fibroblasts, and less extensive in mouse 3T3 cells. The glycerol-induced particle redistribution is not inhibited at 4 degrees, but it is inhibited by pretreatment with 2.5% glutaraldehyde. A significant number of the cells remain viable after the glycerol treatment, and the process is reversible. Particle aggregation does not appear to be related to either growth rate or cell density. Transformed Rous sarcoma virus/chick embryo fibroblasts and simian virus 40/3T3 cells have few particle aggregates after glycerol treatment. The plasma membranes of chick embryo fibroblasts transformed with a mutant of Rous sarcoma virus (TS-68) that is temperature sensitive for transformation, have few particle aggregates when grown at the permissive temperature (37 degrees). Extremely prominent particle aggregates are present in the plasma membranes of cells grown at the nonpermissive temperature (41 degrees). These observations indicate that there is an alteration in the plasma membrane associated with viral transformation which is related to a glycerol-sensitive mechanism that controls the distribution of intramembrane particles.
通过冷冻断裂技术，对培养的非恶性细胞与病毒转化的恶性细胞的质膜膜内组织结构进行了比较。在冷冻前不对细胞进行固定或进行轻度固定（戊二醛处理）时，这些细胞的质膜内膜颗粒分布没有显著差异。然而，用甘油处理后，未转化细胞的膜内颗粒会重新分布形成聚集体。在正常鸡胚成纤维细胞中颗粒聚集广泛，在小鼠3T3细胞中则较少。甘油诱导的颗粒重新分布在4℃时不受抑制，但用2.5%戊二醛预处理可抑制。甘油处理后大量细胞仍存活，且该过程是可逆的。颗粒聚集似乎与生长速率或细胞密度均无关。甘油处理后，转化的劳氏肉瘤病毒/鸡胚成纤维细胞和猿猴病毒40/3T3细胞几乎没有颗粒聚集体。用对转化温度敏感的劳氏肉瘤病毒突变体（TS - 68）转化的鸡胚成纤维细胞，在允许温度（37℃）下生长时，质膜中几乎没有颗粒聚集体。在非允许温度（41℃）下生长的细胞的质膜中存在极其明显的颗粒聚集体。这些观察结果表明，与病毒转化相关的质膜存在改变，这与一种控制膜内颗粒分布的甘油敏感机制有关。
