Cobb R R, Martin J, Korytynski E, Monteith L, Hughes T J
Center for Life Sciences and Toxicology, Chemistry and Life Sciences, Research Triangle Park, NC 27709.
Mutat Res. 1989 Aug;226(4):253-8. doi: 10.1016/0165-7992(89)90078-x.
Mouse lymphoma cells of the L5178Y TK+/- -3.7.2C line were exposed to sidestream and mainstream cigarette smoke condensates (CSC). Cells which survived the trifluorothymidine (TFT) challenge fell in 2 classes: large- and small-colony formers. Southern blot analysis of NcoI-digested DNA from mutant colonies yielded 2 distinct restriction fragment banding patterns when probed with the thymidine kinase (TK) cDNA clone pMtk4. One such pattern was composed of 4 bands at 6.4, 5.5, 4.7 and 2.9 kilobase pairs (kb) and was identical to that of TK+/- controls. A second pattern differed from the first only in the absence of the 6.4-kb band. The majority (83/95) of both large and small colonies derived from cells exposed to CSC exhibited restriction fragment banding patterns lacking the 6.4-kb band. The data from the present study suggest that there is no association between mutant colony size and the presence of the 6.4-kb NcoI restriction fragment at the TK locus in the mouse lymphoma mutants analyzed.
将L5178Y TK+/- -3.7.2C系的小鼠淋巴瘤细胞暴露于侧流和主流香烟烟雾浓缩物（CSC）中。在三氟胸苷（TFT）挑战中存活下来的细胞分为两类：大菌落形成细胞和小菌落形成细胞。用胸苷激酶（TK）cDNA克隆pMtk4对突变菌落经NcoI消化的DNA进行Southern印迹分析，当进行探针检测时产生了2种不同的限制性片段条带模式。一种这样的模式由6.4、5.5、4.7和2.9千碱基对（kb）处的4条带组成，与TK+/-对照的模式相同。第二种模式与第一种模式的不同仅在于没有6.4-kb的条带。来自暴露于CSC的细胞的大多数（83/95）大菌落和小菌落都表现出缺乏6.4-kb条带的限制性片段条带模式。本研究的数据表明，在所分析的小鼠淋巴瘤突变体中，突变菌落大小与TK基因座处6.4-kb NcoI限制性片段的存在之间没有关联。
