Haase E, Brendel M
Institut für Mikrobiologie der J.W. Goethe-Universität, Frankfurt/Main, Federal Republic of Germany.
Curr Genet. 1990 Oct;18(3):187-92. doi: 10.1007/BF00318378.
A screening of haploid yeast strains for enhanced resistance to nitrogen mustard (HN2) yielded a recessive mutant allele, hnm1, that conferred hyper-resistance (HYR) to HN2. Diploids, homo- or heterozygous for the HNM1 locus, exhibit normal wild-type like resistance while homozygosity for hnm1 leads to the phenotype HYR to HN2. The hnm1 mutation could be found in yeast strains proficient or deficient in different DNA repair systems. In these mostly HN2-sensitive haploid repair-deficient mutants, hnm1 acted as a partial suppressor of HN2 sensitivity. All isolated recessive mutations conferring hyper-resistance belonged to a single complementation group. The HYR to HN2 phenotype was maximally expressed in growing cells and was associated with reduced mutability by HN2. HNM1 most probably controls uptake of HN2 which would be impaired in the hnm1 mutants.
对单倍体酵母菌株进行筛选以增强对氮芥（HN2）的抗性，得到了一个隐性突变等位基因hnm1，它赋予了对HN2的超抗性（HYR）。对于HNM1基因座纯合或杂合的二倍体表现出正常的野生型抗性，而hnm1纯合则导致对HN2的HYR表型。在不同DNA修复系统熟练或缺陷的酵母菌株中都能发现hnm1突变。在这些大多对HN2敏感的单倍体修复缺陷突变体中，hnm1作为HN2敏感性的部分抑制因子起作用。所有分离出的赋予超抗性的隐性突变都属于一个单一互补群。对HN2的HYR表型在生长细胞中最大程度地表达，并且与HN2导致的变异性降低有关。HNM1很可能控制HN2的摄取，而这在hnm1突变体中会受损。
