Figure 4.—

Ofm phenotype. Cells from a single colony of the ofm14 mutant lacking the 174-kb 5ORIΔ fragment were mated to donor strains carrying either the 174-kb 5ORIΔ or the 174-kb 0ORIΔ fragment. Individual chromoductants were selected and then streaked on color assay plates to score their sectoring phenotypes. Both fragments are marked with SUP11-1, which suppresses the ade2-101 mutation carried by the strain. Chromosome loss events were detected as red sectors on a white colony background. Representative colonies were photographed after 5 days of growth at 30°. Note the high rate of sectoring with the 5ORIΔ fragment compared to the 0ORIΔ fragment.