Stamato T D, Waldren C A
Somatic Cell Genet. 1977 Jul;3(4):431-40. doi: 10.1007/BF01542971.
Techinques are described which permit the identification and isolation of UV-sensitive variants from mutagenized populations of Chinese hamster ovary (CHO) cells. Identification is based on the observation that within two days after receiving a dose of approximately 240 ergs/mm2 of UV irradiation most of the cells in a colony of CHO detach from the surface of a plastic tissue culture dish. At a lower dose of UV, which does not kill or detach a significant number of parental cells, UV-sensitive colonies are killed and become detached. Thus a clear plaque is produced in a lawn of unirradiated parental cells, marking the site occupied by a sensitive colony. Live cells from such sensitive colonies have been recovered from a nylon cloth replica prepared prior to irradiation and characterized. One UV-sensitive variant (CHO-UV-1) is indistinguishable from parental cells in X-ray resistance, chromosome number, generation time, and duration of the phases of the cell cycle. For UV irradiation the hit number (-n), shoulder width (Dq), and mean lethal dose (Do) for the variant are 2.8, 21 ergs/mm2, and 21 ergs/mm2, respectively, as compared to 2.6, 36 ergs/mm2, and 45 ergs/mm2 for CHO-K1 cells. These values have not changed for a period of eight months in culture.
本文描述了一些技术，这些技术可用于从诱变的中国仓鼠卵巢（CHO）细胞群体中鉴定和分离对紫外线敏感的变体。鉴定的依据是观察到，在接受约240尔格/平方毫米剂量的紫外线照射后两天内，CHO细胞集落中的大多数细胞会从塑料组织培养皿表面脱离。在较低剂量的紫外线照射下，该剂量不会杀死或使大量亲代细胞脱离，而对紫外线敏感的集落则会被杀死并脱离。因此，在未照射的亲代细胞的菌苔中会形成一个清晰的噬菌斑，标记出敏感集落占据的位置。已从照射前制备的尼龙布复制品中回收并鉴定了来自此类敏感集落的活细胞。一种对紫外线敏感的变体（CHO-UV-1）在抗X射线能力、染色体数目、世代时间和细胞周期各阶段的持续时间方面与亲代细胞没有区别。对于紫外线照射，该变体的击中数（-n）、坪宽（Dq）和平均致死剂量（Do）分别为2.8、21尔格/平方毫米和21尔格/平方毫米，而CHO-K1细胞的相应数值分别为2.6、36尔格/平方毫米和45尔格/平方毫米。在培养八个月的时间里，这些数值没有变化。
