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：8
页码：2838-2842
DOI：10.1073/pnas.73.8.2838
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Gene transfer between two closely related mouse cell lines has been carried out, using as the vector a cell-free preparation of metaphase chromosomes and nuclei. Distinction between gene transferents and revertants of the recipient mutant phenotype was achieved by the use of a donor strain carrying a mutationally altered (8-azaguanine-resistant) hypoxanthine-guanine phosphoribosyltransferase (HPRTase; IMP:pyrophosphate phosphoribosyltransferase, EC 2.4.2.8 ). The transferred HPRTase gene is initially unstable; in nonselective medium, it is lost at a rate of about 0.1 per cell per generation. Stabilization occurs as a rare event, with a frequency on the order of 1 X 10(-5) per cell per generation. The unstable state can be maintained for at least 200 generations through serial passages of the transferent in selective medium. Under the conditions of cultivation used in these experiments, the unstable HPRTase-positive cells are eventually replaced by the stable HPRTase-positive cells in the population.
