期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1975
卷号:72
期号:9
页码:3594-3598
DOI:10.1073/pnas.72.9.3594
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要: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.