Fig. 1. Defective phenotypes of the wat1 mutant and gene disruption. (A) Diploidisation. Wild-type (top) pop1-364 (middle) or wat1-5235 cells (bottom) were grown in rich medium at 27°C and processed for flow cytometry (FACS). The left panels show the DNA content of individual cells on the x-axis in a logarithmic scale and frequency at the y-axis, while the right panels show forward scattering on the x-axis and a DNA content on the y-axis. (B) Temperature and cold sensitivity. Wild type (left) or wat1-5235 cells (right) were streaked on rich plates and incubated at 19°C, 27°C or 36°C. (C) Tetrad analysis. Two sets of tetrads, derived from heterozygous diploids for the wat1⁺ gene (I030, Table 1) and grown at 27°C are shown. (D) Diploidisation of the wat1 disruptant. wat1-deleted mutants were streaked on rich medium containing phloxine B and incubated at 27°C for 3 days. White colonies (arrows) show haploid cells, while dark red colonies (arrowheads) are diploid cells (confirmed by FACS).