摘要
为探讨稀土抗诱变作用机理，本研究以穿梭质粒ｐＳＰ１８９，经具致癌作用的烷化剂甲基硝基亚硝基胍（ＭＮＮＧ）或ＭＮＮＧ加柠檬酸稀土同时处理后，转染猴肾ＶｅｒｏＥ６细胞，从细胞中回收的质粒转化大肠杆菌ＭＢＭ７０７０。结果表明，ＭＮＮＧ浓度在１．５～６．０μｇ／ｍｌ范围，突变率明显的高于溶剂对照。稀土浓度分别为１０，２０及４０μｇ／ｍｌ与３μｇ／ｍｌＭＮＮＧ同时处理质粒，发现突变率分别为１５．２×１０－４、１０．０×１０－４及１２．７×１０－４，明显低于ＭＮＮＧ单独处理时的２５．１×１０－４，推测稀土可能阻断ＭＮＮＧ引起的Ｇ．Ｃ→Ａ．Ｔ转换，保护质粒ｐＳＰ１８９的靶基因ＳｕｐＦｔＲＮＡ免受损伤或影响某些基因表达。
To study the mechanism of rare earths on antimutation effect,this experiment was performed by shuttle vector plasmid pSP189 as a target,treated by alkylating reagent such as methyl nitro nitrous guanidine(MNNG) or by both MNNG and rare earth citrate,then it was transfected into Vero E6 cells,from which the recoveried plasmid could be transformated to E.Coli MBM7070.Results showed that mutation frequency was significantly higher than those of solvent control at the concentration of 15～6 0μg/ml MNNG.With different concentration of rare earth(10,20 and 40μg/ml) and 3μg/ml of MNNG treated plasmid together,its mutation frequency were 152×10 -4 ,10 0×10 -4 and 12 7×10 -4 respectively,which were remarkable lower than 25 1×10 -4 with MNNG along.Then it could be considered that the rare earth could inhibit the transformation from G.C to A.T caused by MNNG and protect the target gene of SupF tRNA of plasmid pSP189 from damage,or affect the expression of some gene.\ \
出处
《卫生毒理学杂志》
CSCD
1998年第3期138-140,共3页
Journal of Health Toxicology
关键词
稀土化合物
穿梭质粒
突变
MNNG
Rare earth compounds MNNG Shuttle vector plasmid Mutation
