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:1982
卷号:79
期号:3
页码:845-849
DOI:10.1073/pnas.79.3.845
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:The differentiation of most mammalian cells is preceded by growth arrest in the G1 phase of the cell cycle, but the characteristics of this state have not been established. We now report that the growth arrest that precedes the differentiation of BALB/c 3T3 T mouse proadipocytes must occur at a distinct state in G1 designated GD. GD-arrested cells are characterized by their ability to differentiate in the absence of DNA synthesis and by their unique sensitivity to the mitogenic effect of isobutylmethylxanthine. Proadipocytes induced to become G1 growth arrested at other states by culture in medium deficient in growth factor or nutrients, by contrast, are unable to differentiate in the absence of DNA synthesis and are not stimulated to proliferate by isobutylmethylxanthine even when they are exposed to differentiation-promoting medium prior to arrest. These data support the conclusion that, prior to the expression of a differentiated phenotype, proadipocytes must arrest their growth at a distinct state in the G1 phase of the cell cycle, GD. These data also provide the basis for the hypothesis that carcinogenesis is associated with defects in the coupling of growth arrest and differentiation at the GD state.