Harris M
Somatic Cell Genet. 1979 Nov;5(6):793-808. doi: 10.1007/BF01542642.
Hybrids between Chinese hamster cells were isolated and maintained in media that were selective or nonselective for markers present in the parent cells (HGPRT and TK deficiencies, respectively). Segregation frequencies for resistance to azaguanine (AZG), thioguanine (THG), or bromodeoxyuridine (BrdU) could be enhanced for some groups of hybrids if the stock cells were maintained under nonselective conditions rather than in HAT medium. In these populations the expression of resistance was dominant or codominant even though marker patterns were recessive for the same cells in HAT. Clonal analysis showed that enhancement took place by adaptive shifts rather than by variation and selection. Segregation frequencies in hybrids were also found to differ significantly between clones isolated by replicate fusions of any two parental cell types. The basis for this heterogeneity is unknown and deserves further study.
分离出中国仓鼠细胞的杂种细胞，并将其培养在对亲代细胞中存在的标记物（分别为次黄嘌呤鸟嘌呤磷酸核糖转移酶和胸苷激酶缺陷）具有选择性或非选择性的培养基中。如果原代细胞在非选择性条件下而非在次黄嘌呤-氨基蝶呤-胸腺嘧啶核苷（HAT）培养基中培养，那么对于某些杂种细胞群体，对氮杂鸟嘌呤（AZG）、硫代鸟嘌呤（THG）或溴脱氧尿苷（BrdU）的抗性分离频率可能会提高。在这些群体中，抗性表达是显性或共显性的，尽管在HAT中相同细胞的标记模式是隐性的。克隆分析表明，增强是通过适应性转变而非变异和选择发生的。还发现，通过任何两种亲代细胞类型的重复融合分离出的克隆之间，杂种细胞中的分离频率也存在显著差异。这种异质性的基础尚不清楚，值得进一步研究。
