Gocke E, Manney T R
Genetics. 1979 Jan;91(1):53-66. doi: 10.1093/genetics/91.1.53.
In the yeast Saccharomyces cerevisiae, the expression of resistance to the L-arginine analog, L-canavanine, after mutagenesis, is strongly dependent on the metabolic state of the cell. The frequency of mutations recovered after exposure to ultraviolet light or X rays was measured under a variety of culture conditions. The results indicate that the frequency of mutants recovered is determined by the following three factors: (1) The potential mutants still possess enough permease activity to take up some of the cell poison, and some are therefore killed before they can express the mutant genotype. The sensitivity is strongly influenced by the endogenous free arginine, which is in turn influenced by the growth medium. (2) The rapid decay of the permease molecules and the inability of the potential mutants to resynthesize this protein results in a rapidly increasing change of expression when selection is delayed. (3) During the time when the permease activity is decaying, repair of the mutagen-induced damage appears to occur.
在酿酒酵母中，诱变后对L - 精氨酸类似物L - 刀豆氨酸的抗性表达强烈依赖于细胞的代谢状态。在各种培养条件下，测量了暴露于紫外线或X射线后恢复的突变频率。结果表明，恢复的突变体频率由以下三个因素决定：（1）潜在突变体仍具有足够的通透酶活性以摄取一些细胞毒素，因此一些在能够表达突变基因型之前就被杀死。敏感性受到内源性游离精氨酸的强烈影响，而内源性游离精氨酸又受到生长培养基的影响。（2）通透酶分子的快速衰变以及潜在突变体无法重新合成这种蛋白质导致选择延迟时表达变化迅速增加。（3）在通透酶活性衰变期间，诱变诱导的损伤修复似乎会发生。
