Ferric reductase and nuclear retention of ribosomal protein (Rpl25)
(A) Ferric reductase quantitative assays. Cells were grown in YPAD, washed with buffered citrate solution at pH6.5 and incubated with 1 mM ferric chloride and 1 mM bathophenathroline disulfonate, after which the OD515 absorbance was assessed. Data are expressed as mean ± SEM (N = 6 per group). **P<0.01, ***P<0.001 versus Gal-Grx3↑Δgrx4; #P<0.05, ##P<0.01, ###P<0.001 versus Gal-Grx3↓Δgrx4. (B) Nuclear localization of ribosomal protein Rpl25. Cells were transformed with pRS426-Rpl25-eGFP. Cells were fixed in ice-cold 70% ethanol for 10 min, briefly stained with DAPI and examined using a fluorescence microscope. Raw Integrated Density of GFP signal for 100 cells selected randomly by blanking the background values was measured using the ImageJ Software. Data are expressed as mean ± SEM (N = 100 per group). ***P<0.001 versus Gal-Grx3↑Δgrx4; ###P<0.001 versus Gal-Grx3↓Δgrx4. (C) Photographs of representative cells to demonstrate nuclear retention of Rpl25. DAPI and Rpl25-eGFP fluorescent images are shown.