Bandas E L
Genetika. 1983 Aug;19(8):1384-6.
A diploid strain of Saccharomyces cerevisiae, T6 is described which monitors both mitotic crossing over and induction of aneuploidy. The chromosome III carries recessive markers: rgh12 of "rough colony" phenotype closely linked to centromere, the left arm is marked with his4, the right arm is marked both with thr4 and the locus of mating type alpha. Expression of all the markers on chromosome III leads to formation of colonies which are rough, require histidine and threonine, and are of alpha mating type. These colonies arise as a result of the loss of a chromosome during mitosis, which makes the strain allow detection of monosomic cells formation. Chromosome XV carries two phenotypically distinguishable and recessive alleles of the gene ade2: ade2-192 (causes red coloration of colonies) and ade2-G45 (causes pink coloration of colonies). Mitotic crossing over generates two reciprocal products which can be revealed together in colonies as pink and red sectors in double-spotted colonies. Both double-spotted and monosomic colonies have been obtained after treatment with gamma-rays. The frequency of mitotic crossing over after irradiation by 1000-3000 Gray increased up to 2-3.2% (the spontaneous level was 0.006%), the frequency of aneuploidy was 0.12 to 0.57% at plating immediately after irradiation (the spontaneous monosomics were not observed among 1.5 X 10(5) cells scored). Induction of mitotic crossing over and aneuploidy by benomyl was rather slight (up to 0.05 and 0.006%, respectively).
描述了一种酿酒酵母的二倍体菌株T6，它可监测有丝分裂交换和非整倍体的诱导。第三条染色体携带隐性标记：与着丝粒紧密连锁的“粗糙菌落”表型的rgh12，左臂标记有his4，右臂同时标记有thr4和α交配型位点。第三条染色体上所有标记的表达会导致形成粗糙、需要组氨酸和苏氨酸且为α交配型的菌落。这些菌落是有丝分裂期间一条染色体丢失的结果，这使得该菌株能够检测单体细胞的形成。第十五条染色体携带基因ade2的两个表型可区分的隐性等位基因：ade2 - 192（导致菌落呈红色）和ade2 - G45（导致菌落呈粉红色）。有丝分裂交换产生两个相互的产物，在菌落中可一起显示为双斑点菌落中的粉红色和红色扇形区域。用γ射线处理后获得了双斑点和单体菌落。照射1000 - 3000戈瑞后有丝分裂交换频率增加到2 - 3.2%（自发水平为0.006%），照射后立即平板接种时非整倍体频率为0.12%至0.57%（在1.5×10⁵个计分细胞中未观察到自发单体）。苯菌灵对有丝分裂交换和非整倍体的诱导作用相当轻微（分别高达0.05%和0.006%）。
