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：6
页码：2056-2060
DOI：10.1073/pnas.73.6.2056
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The clonal variation in rate of albumin synthesis in hepatoma cells is described as a tool for the study of epigenetic control of differentiation. Previous studies have demonstrated that, from a population of hepatome cells, variant subclones can be readily isolated that produce albumin at different rates. Each clonal variant had a characteristic rate of albumin production, and the clones clustered around discrete values that formed a geometric progression. The present experiments, using a cell-free protein-synthesizing system from wheat germ; show that albumin messenger RNA activity is directly proportional to the rate of albumin synthesis in three different hepatoma clones, thus suggesting a pretranslational control of albumin production. Possible hypotheses to explain the geometric pattern of clonal variation are discussed with respect to the organization and control of the transcriptional unit.
