Scharff D J, Delegeane A M, Lee A S
J Cell Biol. 1982 Mar;92(3):629-33. doi: 10.1083/jcb.92.3.629.
K12 is a temperature-sensitive (ts) mutant cell line derived from Chinese hamster fibroblasts. When incubated at the nonpermissive temperature, K12 cells exhibit the following properties: (a) the cells cannot initiate DNA synthesis;o (b) the synthesis of cytosol thymidine kinase is suppressed; and (c) the synthesis of three cellular proteins of molecular weights 94, 78, and 58 kdaltons is greatly enhanced. Here we characterize a spontaneous revertant clone, R12, derived from the K12 cells. We selected the revertant clone for its ability to grow at the nonpermissive temperature. Our results indicate that all the traits which constitute the K12 mutant phenotype are simultaneously reverted to the wild type in the revertant cell line, suggesting that the ts mutation of the K12 cells is of regulatory nature and exerts multiple effects on the expressed phenotypes.
K12是一种源自中国仓鼠成纤维细胞的温度敏感（ts）突变细胞系。当在非允许温度下培养时，K12细胞表现出以下特性：（a）细胞无法启动DNA合成；（b）胞质胸苷激酶的合成受到抑制；（c）三种分子量分别为94、78和58千道尔顿的细胞蛋白的合成大大增强。在此，我们对源自K12细胞的自发回复突变克隆R12进行了表征。我们选择该回复突变克隆是因为它在非允许温度下生长的能力。我们的结果表明，构成K12突变体表型的所有性状在回复突变细胞系中同时回复为野生型，这表明K12细胞的ts突变具有调控性质，并对表达的表型产生多种影响。
