Kinetics of Bud Formation. GAL-GFP-Esc1p strain ATY2102 and an isogenic wild-type strain (ATY2500) were pre-induced in galactose media for 3 hrs, washed and examined on agarose pads in glucose media over 5 hr, during which time escapades remained visible (ATY2500). DIC images captured every 10 min allowed measurement of the timing of bud initiation for each cell. Time measurements were all relative to the emergence of the first bud by each mother cell, M1. For example, the mother's bud interval, M2-M1 measures the delay prior to the appearance of the second bud on the mother. Correspondingly, D-M1 measures the interval prior to the appearance of the first bud on the daughter. (A) Histogram showing the bud intervals for a single experiment for the wild type strain. Note that there is minimal overlap between mothers and daughters and that mothers re-bud considerably faster than daughter cells. (B) Histogram showing the bud intervals for an isogenic escapade strain. Note, in contrast to (A), that there is considerable overlap between mothers and daughters. The bud interval is slowed in mothers and accelerated in daughters. (C) Histogram illustrating the mother-daughter bud differential calculated as: (D-M2 = bud differential) where D is the time at which a bud appears in the daughter cell and M2 is the time at which a second bud appears in the mother cell. Note that the bud differential is decreased by 50% by the presence of escapades (average bud differential is 65 min. in wild-type strain and 28 min. in escapade strain). Results are cumulative over four separate experiments for each strain.
Hattier et al. BMC Cell Biology 2007 8:47 doi:10.1186/1471-2121-8-47