Reciprocal Chromosome Translocation Between the Left-End 220kb of Chromosome II and the Right-End 270kb of Chromosome X in Saccharomyces cerevisiae

Southern hybridization of chromosomes and the physical mapping of the genes used as several probes on the respective chromosomes II and X showed that the left-end ca. 220kb of chromosome II including ATP1 was exchanged the right-end ca. 270kb of chromosome X including ATP2 resulting the reciprocal chromosome translocation in the yeast strain YNN290, Saccharomyces cerevisiae. YTO290, the mutated strain by the reciprocal chromosome translocation as above described, was changed from red to white of the colony-color, and sizes of chromosome II lengthened from ca. 830kb to ca. 900kb and chromosome X shortened from ca. 760kb to ca. 690kb, respectively, in compared with the original strain YNN290. But, YTO290 strain was the same as the original strain YNN290 for other properties; the nutrient requiring of the genotype, the ploidy, the mitochondrial respiratory activity, the cell-size, and the growth-rate (doubling time), the number of chromosomes in a cell, It should be as a total number of nucleotides (bases) of genome.

ATP1 or ATP2 and their neighboring base sequences respectively should be transferred from chromosome II left-end ca. 220kb to chromosome X right-end or chromosome X right-end ca. 270kb to chromosome II left-end accompanying with this reciprocal chromosome translocation. This mutated (the reciprocal chromosomes II and X translocation = exchanged those end-sequences as above described) strain, YTO290, seemed to lead to decrease the stability of the changed chromosomes II and X. The mutated strain, YTO290 might be observed to go back to the respective chromosomes II and X of the original strain, YNN290, in several months later even at 4°C.