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Table 4 Fps1 yields following hyperosmotic shock

From: Constitutively-stressed yeast strains are high-yielding for recombinant Fps1: implications for the translational regulation of an aquaporin

Osmotic shock Time post-shock (min) Fps1 yield relative to control M:P ratio
No shock (2× CBS) 15 1.00 (0.61) 0.24 (0.00)
30 0.59 (0.17) 0.22 (0.03)
60 0.90 (0.48) 0.14 (0.01)
90 1.21 (0.63) 0.10 (0.00)
Hyperosmotic shock (2× CBS, 0.8 M NaCl) 15 3.03 (0.21)* 1.08 (0.14)**
30 2.62 (0.83) 1.24 (0.16)***
60 1.73 (0.29) 0.29 (0.03)
90 2.08 (0.58) 0.21 (0.02)*
  1. Wild-type yeast cells were transformed with a plasmid expressing 5′∆1-43-FPS1-HA3; uORF2 was therefore present (Table 1). Single transformants were cultured in shake flasks in 2 × CBS lacking histidine (to maintain the plasmid). At A600 ~ 4, cultures were divided into two, harvested by centrifugation and the pellets suspended in either 2× CBS (no shock) or 2× CBS supplemented with 0.8 M NaCl (hyperosmotic shock). Fps1 yields were determined by immunoblot and analyzed using ImageJ [6] after 15, 30, 60 and 90 min; values are reported relative to control conditions (wild-type cells after 15 min in 2× CBS). All data shown are the mean of biologically-independent, triplicate determinations; where relevant, the standard error of the mean (SEM) is shown in parentheses. A two-tailed paired t test was used to compare Fps1 yields or polysome ratios of shocked cells with the corresponding values for control cells at the equivalent time point
  2. * P ≤ 0.05; ** P ≤ 0.01; *** P ≤ 0.001