Ibrahim M A, Coddington A
Heredity (Edinb). 1976 Oct;37(2):179-91. doi: 10.1038/hdy.1976.81.
Cycloheximide-resistant mutants of Schizosaccharomyces pombe were isolated either as spontaneous mutants or after mutagenic treatment with nitrous acid, UV and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). Twenty-three spontaneous mutants and 64 induced mutants were analysed genetically. Crosses revealed that at least four loci, designated cyh1, cyh2, cyh3 and cyh4 are responsible for resistance. Alleles of cyh1 show good growth on either high (100 mug/ml) or low (40 mug/ml) concentrations of cycloheximide whereas alleles at the cyh2, cyh3 and cyh4 loci gorw well on 40 mug/ml but poorly on 100 mug/ml. Some alleles at the cyh2 and cyh3 loci are also temperature sensitive (ts), the ts phenotype being conferred by the same gene as the resistance. In diploids, cyh1 and cyh4 are re-essive to wild type whereas cyh2 and cyh3 are semi-dominant. There was no intragenic complementation between three cyh1 alleles. Cross-resistance to trichodermin and anisomycin was shown by cyh2, cyh3 and cyh4 but not cyh1. Most cyh1 alleles, of spontaneous and UV origin only, were cold sensitive (cs) at 14 degrees and some of these were also cycloheximide dependent at the same temperature. It is suggested that the cyh1 and cyh4 genes are involved in ribosome formation or function and the other loci probably affect the uptake of cycloheximide by the cells.
粟酒裂殖酵母的环己酰亚胺抗性突变体通过自发突变或经亚硝酸、紫外线及N-甲基-N'-硝基-N-亚硝基胍（MNNG）诱变处理后分离得到。对23个自发突变体和64个诱导突变体进行了遗传分析。杂交结果表明，至少有四个位点，即cyh1、cyh2、cyh3和cyh4与抗性有关。cyh1的等位基因在高浓度（100微克/毫升）或低浓度（40微克/毫升）的环己酰亚胺中均能良好生长，而cyh2、cyh3和cyh4位点的等位基因在40微克/毫升时生长良好，但在100微克/毫升时生长较差。cyh2和cyh3位点的一些等位基因也是温度敏感型（ts），ts表型与抗性由同一基因赋予。在二倍体中，cyh1和cyh4对野生型是隐性的，而cyh2和cyh3是半显性的。三个cyh1等位基因之间不存在基因内互补。cyh2、cyh3和cyh4表现出对木霉菌素和茴香霉素的交叉抗性，而cyh1则没有。仅自发和紫外线来源的大多数cyh1等位基因在14摄氏度时是冷敏感型（cs），其中一些在相同温度下也是环己酰亚胺依赖性的。有人提出，cyh1和cyh4基因参与核糖体的形成或功能，而其他位点可能影响细胞对环己酰亚胺的摄取。
