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：1978
卷号：75
期号：12
页码：6064-6068
DOI：10.1073/pnas.75.12.6064
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The objective of this study was to determine if HeLa cells irreversibly arrested in G2 phase of the cell cycle by a brief exposure to a nitrosourea compound were deficient in certain proteins when compared with G2-synchronized cells. Total cellular proteins of G2-synchronized, G2-arrested, and S phase-synchronized cells were compared by two-dimensional polyacrylamide gel electrophoresis. The S phase cells differed from the G2-synchronized and G2-arrested cells by the absence of about 35 and 25 protein spots, respectively, of a total of nearly 150. At least nine protein spots in the molecular weight range of 4--5 X 10(4) that were present in the G2-synchronized cells were absent in both the G2-arrested and the S phase cells. Thus, these studies suggest that the missing proteins are probably necessary for the transition of cells from G2 phase to mitosis. Supplying the missing proteins to the G2-arrested cells by fusion with G2-synchronized cells facilitated the entry of the former into mitosis.
