Hamada K, Isomura K, Teranishi K, Watanabe H
Mutat Res. 1978 Aug;54(1):61-72. doi: 10.1016/0165-1161(78)90136-x.
Induction, isolation and characterization of frameshift mutants were studied by using a Chinese hamster Don (CHD) cell line. ICR-191, known to be a potent frameshift mutagen, was used for the induction of frameshift mutations. The drug (10(-5) M), as well as N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and ethyl methanesulfonate (EMS), increased significantly the frequency of forward mutations from 8-azaguanine (8-AG) sensitivity (8-AGs) to resistance (8-AGr) over the untreated control to an extent of about 100-fold. 21 8-AGr mutants were isolated from the AP-01 (a sub-line of CHD) cells after treatment with appropriate concentrations of ICR-191 (10(-5) and 1.36 X 10(-5) M), and subsequently several reclonal mutants were tested for their ability to revert to 8-AG susceptibility after treatment with the three mutagens and a carcinogen, 2-nitrofluorene (2-NF), known to be a frameshift mutagen. Among the 8-AGr mutants tested, clone ICR-014 or ICR-172 showed a significant increase in reversion frequency over the control level only after treatment with ICR-191 or 2-NF, respectively; but not with the other two mutagens. These results suggest that each of these two kinds of mutant has a different frameshift mutation in one of the loci controlling 8-AG resistibility. It was also found that the hypoxanthine--guanine phosphoribosyl transferase (HGPRT) activities in clones ICR-014 and ICR-172 were 1.9 and 34% of that of the original AP-01 cells, respectively.
利用中国仓鼠唐（CHD）细胞系研究了移码突变体的诱导、分离和特性。已知ICR - 191是一种强效移码诱变剂，用于诱导移码突变。该药物（10⁻⁵ M）以及N - 甲基 - N'- 硝基 - N - 亚硝基胍（MNNG）和甲磺酸乙酯（EMS），使从对8 - 氮杂鸟嘌呤（8 - AG）敏感（8 - AGs）到抗性（8 - AGr）的正向突变频率相较于未处理对照显著增加，增幅约为100倍。在用适当浓度的ICR - 191（10⁻⁵和1.36×10⁻⁵ M）处理AP - 01（CHD的一个亚系）细胞后，分离出21个8 - AGr突变体，随后对几个克隆突变体在用三种诱变剂和一种已知为移码诱变剂的致癌物2 - 硝基芴（2 - NF）处理后恢复为8 - AG敏感性的能力进行了测试。在测试的8 - AGr突变体中，克隆ICR - 014或ICR - 172仅在分别用ICR - 191或2 - NF处理后，回复频率相较于对照水平有显著增加；而用其他两种诱变剂处理则无此现象。这些结果表明，这两种突变体中的每一种在控制8 - AG抗性的一个位点上都有不同的移码突变。还发现克隆ICR - 014和ICR - 172中的次黄嘌呤 - 鸟嘌呤磷酸核糖转移酶（HGPRT）活性分别为原始AP - 01细胞的1.9%和34%。
