Figure 1. Yeast require vacuoles of a specific size prior to formation of a bud.

(A) Wild-type and vac17Δcells which express Vph1-GFP from its endogenous locus, were pulse labeled with the vacuole specific dye FM4-64. Wild-type cells have both FM4-64 and Vph1-GFP signals in both mother and daughter cells. vac17Δ cells have both Vph1-GFP and FM4-64 on the vacuole in old mother cells, however the daughter cells solely have a Vph1-GFP labeled vacuole. White arrowheads; new vacuoles in daughter cells. Yellow arrowheads; new vacuoles in new mother cells. Dashed line; outline of cells. (B) (Left panel) A new cell does not form a bud until its vacuole reaches a specific size. Graph indicates the vacuole diameter of wild-type, vac17Δ old cell and vac17Δ new cells with no bud and mother cells with a small bud (less than 20% of diameter of the mother cell). Cell/vacuole diameter was measured by ImageJ. Each cell/vacuole diameter was normalized to its mother cell diameter. Black arrow; minimum size of mother vacuoles in cells with a bud. Average in each category (red bar). Error bar; standard deviation (SD). Not a significant difference; ns, p-value > 0.10. A statistically significant difference; *** (p-value < 1 × 10⁻³). (Right panel) The vacuoles of the new mother cells of vac17Δ grow faster than vacuoles in either a wild-type or vac17Δ old mother cell. Scatter plots of bud sizes and mother vacuole sizes.

DOI: http://dx.doi.org/10.7554/eLife.08160.003

Figure 1—figure supplement 1. Yeast require vacuoles of a specific size prior to formation of a bud.

(A) Schematic of diameters measured. (B) Vacuole diameter is proportional with the cell diameter. Scatter plot of cell diameter and vacuole diameter in mother and daughter cells. (C) When viewed across the cell-cycle, the increase in vacuole size of vac17Δ new cells is greater than either wild-type or vac17Δ old cells. Trend lines from linear equations of data from wild-type (black line); vac17Δ old mother cells (pink line), and vac17Δ new mother cells (green line) are shown. (D) Vacuole inheritance is important for regulating vacuole size in the mother cell. The vacuole size of vac17Δ old mother cells is larger than that of wild-type. Average in each category (red bar). Error bar; SD. *** (p-value < 1 × 10⁻⁴). Middle line in box plot indicates the median of the data set. The upper edge of the box indicates the 75th percentile of the data set, and the lower edge indicates the 25th percentile.

DOI: http://dx.doi.org/10.7554/eLife.08160.004