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:1977
卷号:74
期号:6
页码:2417-2421
DOI:10.1073/pnas.74.6.2417
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Nascent calcium phosphate promotes the agglutination and fusion of human erythrocyte ghosts. Membrane phospholipids of erythrocyte ghosts treated with Ca2+ and phosphate ions become exposed to attack by phospholipase C (phosphatidylcholine cholinephosphohydrolase, EC 3.1.4.3 ) (Bacillus cereus). Freeze-fracture pictures of fused erythrocyte ghosts show the presence of regions deficient in intramemebrane particles in the protoplasmic face which we believe to be regions of fusion. Discontinuous regions of the protoplasmic and exoplasmic faces are observed, which are apparently intermediate stages in the process of fusion. TH-in-section electron micrographs reveal deposits of calcium phosphate in areas of contact and fusion of ghosts. Ca2+ in the presence of N-[tris(hydroxymethyl)methyl]glycine (Tricine) buffer causes the formation of blebs in the membrane but does not cause changes in the intramembrane particle pattern or induce fusion. It is suggested that nascent calcium phosphate acts by forming protein-free regions of phospholipid bilayer which can fuse readily.