Glebov O K, Abramian D S
Tsitologiia. 1985 Jul;27(7):797-804.
From 6 clones of Chinese hamster cells varying in the rate of the loss of transformant phenotype and containing a thymidine kinase gene (tk-gene) of Herpes simplex virus type 1 (HSV1), 25 subclones negative in thymidine kinase (TK-) were isolated on a medium with 50 micrograms/ml 5-bromodeoxyuridine (BrdU). A study was made of the frequency of spontaneous reversions to the TK+ phenotype in cell populations of BrdU-resistant subclones, and of the transforming activity (upon transformation of TK- cells of A238 clone to the TK+ phenotype) of DNA preparations from a row BrdU-resistant subclones. In 7 of 11 BrdU-resistant subclones the TK- phenotype is associated with changes reducing significantly the transforming activity of DNA. Some of these alterations are stable and undergo no spontaneous reversion, while the other ones are unstable, being reversed or suppressed at a high frequency. BrdU-resistant subclones produced from clones more stable in transformant phenotype are on the whole more stable in the TK- phenotype than BrdU-resistant subclones from the clones with the high rate of the loss of the TK+ phenotype.
从6个中国仓鼠细胞克隆中分离出25个胸苷激酶阴性（TK-）的亚克隆，这些克隆的转化体表型丧失速率不同，且含有1型单纯疱疹病毒（HSV1）的胸苷激酶基因（tk基因）。这些克隆是在含有50微克/毫升5-溴脱氧尿苷（BrdU）的培养基上分离得到的。研究了BrdU抗性亚克隆细胞群体中自发回复到TK+表型的频率，以及一系列BrdU抗性亚克隆的DNA制剂对A238克隆的TK-细胞转化为TK+表型的转化活性。在11个BrdU抗性亚克隆中，有7个的TK-表型与DNA转化活性显著降低的变化有关。其中一些变化是稳定的，不会自发回复，而另一些则是不稳定的，会以高频率回复或被抑制。从转化体表型更稳定的克隆产生的BrdU抗性亚克隆，总体上在TK-表型上比来自TK+表型丧失速率高的克隆的BrdU抗性亚克隆更稳定。
