Figure 3 .

Analysis of the phenotypes of ypa1–Δ and ypa2–Δ. Cells of the indicated genotype were grown at 32° and then shifted to 19° for 18 hr. Cell were fixed and stained with DAPI and calcofluor. Bar, 10 μm throughout. (A) Analysis of ypa1–Δ and ypa2–Δ. The arrows in ypa2–Δ indicate cells that have delayed complete separation. (B) Analysis of ypa2–Δ ppa2–Δ. Note the presence of asymmetrically placed septa, cells with elongated “stretched” nuclei, indicative of problems with chromosome separation, and (inset) two multinucleate cells that have failed to separate. (C) Circled 1 indicates a representative cell with an eccentrically placed septum. Note that in these cells, the nuclei are also flattened and positioned at the cell periphery. The arrowed 2 indicates representative cells showing lagging chromosomes. The circled 3 (inset) shows a pair of cells that have failed to separate, one of which has initiated the subsequent mitosis. The circled 4 indicates a cell with aberrant morphology. (D) ppa2-6 cells at 32°. (E) Tetrads from a cross ypa1–Δ ppa2-6 were dissected at 32°. Colonies were photographed prior to replica plating. The genotype of the microcolony was inferred from the phenotypes after replica plating.