FIG 4 .

UPR and ERAD are involved in the gamma radiation resistance of C. neoformans. (A) The WT (H99), ire1Δ (YSB552), ire1Δ+IRE1 (YSB1000), and hxl1Δ (YSB723) mutant, and hxl1Δ+HXL1 complemented (YSB762) C. neoformans strains were grown overnight at 30°C in liquid YPD medium, and the 10-fold serially diluted cells were spotted onto solid YPD medium. Cells were exposed to gamma radiation and then further incubated at 30°C for 1 to 3 days. (B and C) Fold increase in expression of UPR downstream and ubiquitin-related genes after radiation exposure. The expression patterns of target genes were quantitatively determined using qRT analysis with the gene-specific primers listed in Table S2. To monitor the fold increase in expression of molecular chaperone genes, the cDNA was synthesized with total RNAs extracted from cells recovered 60 min after exposure to gamma radiation or not exposed to gamma radiation. Duplicate technical experiments with two or more biological samples were conducted. Representative images from independent experiments for each target gene are shown. Error bars indicate standard deviations. Asterisks indicate statistical significance of differences in expression levels of each gene (*, P < 0.05; **, P < 0.01; ***, P < 0.001). NS, not significant.