Fig. 6.

The phosphorylation of Cip1 is responsible for hyperosmotic stress-induced transitory G1 delay. a Budding index of WT, cip1, cip1-3TA, sic1, and sic1 cip1 strains under treatment of 0.5 M KCl. The percentage of budded cells were given as mean ± s.d. (n = 3, *P < 0.05, Student’s t-test, two-tailed). b WT, cip1, sic1 and cip1 sic1 strains were elutriated in YEP, raffinose. Newborn cells were collected and recovered in YEPD at 25 °C. At time 0, cultures were subjected to or not to osmostress (0.5 M KCl). Cell cycle progression was monitored by FACS analysis for 150 min after stress. An arrow indicates the timing when the G1–S transition speeds up in cip1 sic1 cells. c Exponentially growing cells were diluted to OD₆₀₀ = 0.1 and grown at 30 °C in minimal media. Osmosensitivity was tested in the presence of 1.2 M KCl. OD measurements were estimated every hour for 25 h in a 96-well plate using Synergy H1 Multi-Mode Reader. d In WT and cip1 strains, α-factor synchronized G1 cells were released in 0.5 M KCl YEPD medium at 24 °C. At 15 min intervals, samples were collected, and α-factor/nocodazole trap assay was performed. More than 300 cells showing mating projections (G1 cells) or buds (post-G1 cells) were counted for each time point, and the experiment was repeated three times