论文部分内容阅读
用诱变剂MNNG对含EB病毒类穿梭质粒的pESnx/FL克隆细胞进行致突变研究,MNNG对FL细胞的IC_(50)为1.25μg/ml,对以XylE为靶基因的克险细胞的诱发突变率为2～7×10~(-3),至少是克隆细胞自发突变率的27.8倍。随着MNNG的诱变剂量的增加,转化子数减少,突变子数增加,诱发突变率增加,诱变剂量与诱发突变率呈正相关剂量反应趋势。突变子的Cracking gel快速鉴定法表明,通过两次穿梭,质粒DNA仍能完整存在,且分子量无明显改变。因此,在DNA水平上,MNNG对靶基因XylE无大片段改变。
Mutagenesis of pESnx / FL clones containing EBV shuttle plasmids was carried out by mutagen MNNG. IC50 (50) of MNNG on FL cells was 1.25μg / ml, which was induced by XylE Mutation rate of 2 ~ 7 × 10 ~ (-3), at least 27.8 times the spontaneous mutation rate of cloned cells. With the increase of mutagenic dose of MNNG, the number of transformants decreased, the number of mutants increased, the rate of induced mutation increased, and the dose of mutagenicity and the rate of induced mutation showed a positive dose-response trend. The rapid identification of the mutant by Cracking gel showed that the plasmid DNA could still exist intact by two shuttles without obvious change in molecular weight. Therefore, at the DNA level, MNNG has no large fragment change on the target gene XylE.