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:1976
卷号:73
期号:3
页码:867-871
DOI:10.1073/pnas.73.3.867
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:A structure which appears to organize cytoplasmic microtubules in interphase mouse 3T3 cells can be visualized by immunofluorescence microscopy. Purified monospecific antibody against homogeneous tubulin from brain visualizes, in addition to cytoplasmic microtubules, a cytoplasmic polar structure as the focal point from which the microtubules seem to radiate. The structure is preserved after treatments that depolymerize cytoplasmic microtubules, i.e., exposure of cells to mitotic drugs or to low temperature. When cells recover from these treatments one end of each microtubule organizing structure acts as a nucleating center from which cytoplasmic microtubules grow toward the plasma membrane. Thus cytoplasmic microtubules assemble in vivo in an ordered unidirectional manner, and therefore the cell must be able to avoid the assembly of unwanted, unoriented, and disconnected microtubules. These results suggest that the assembly of tubulin into microtubules is regulated in vivo.