FIG. 3.

Phenotypes of strains carrying deletions of the UPC2 gene. Strains were grown overnight in YPD supplemented with uridine. Cells were serially diluted and spotted on plates as described in Material and Methods. (A) Wild-type strain (WT) and strains carrying one to four deletions of the UPC2 gene (Table 1) were spotted on YPD-uridine plates without drugs or YPD-uridine plates containing ketoconazole, fluconazole, or fluphenazine, as indicated on the figure. Cells were grown for 24 h (upper left panel) or 48 h (upper right and lower panels). (B) Spotting experiments were carried out with two independent integrants (Table 1). A wild-type strain with an integrated pCaEXP plasmid, WT + pCaEXP (strains CSM2-2 and CSM2-3); a UPC2 deletion strain with an integrated pCaEXP plasmid, Δupc2 + pCaEXP (strains CSM13-1 and CSM13-2); and a UPC2 deletion strain with an integrated UPC2 overexpression vector, Δupc2 + pCaEXP-UPC2 (strains CSM15-1 and CSM15-2) were spotted on minimal medium plates (lacking methionine, cysteine, and uridine) without drugs or containing ketoconazole, fluconazole, or fluphenazine, as indicated on the figure. Cells were grown for 24 h (upper left panel), 48 h (upper right and lower left panels), or 72 h (lower right panel). (C) Strains used in Fig. 3B were grown for 24 h in the presence of oxygen or for 48 h in the absence of oxygen on minimal plates (lacking methionine, cysteine, and uridine).