FIG 6.

Loss of GADD34 function protects mice against tunicamycin-induced renal toxicity. WT and GADD34^−/− mice were injected intraperitoneally with Tm (1 mg/kg body weight) or DMSO as described in Materials and Methods. (A) Representative images (magnification, ×200) of kidney slices from WT and GADD34^−/− mice 4 days after Tm administration and after staining with H&E are shown. Scale bar, 200 μm; n = 4 to 12. (B) Paraffin-embedded sections of fixed mouse kidneys were stained with anti-cleaved caspase-3 antibody. Representative images (×200) show cells positive for cleaved caspase-3 (dark brown) at sites of renal lesions observed 4 days after Tm injection. Scale bar, 200 μm; n = 2 to 4. (C) Quantification of cleaved caspase-3 in mouse kidneys as a percentage of the image stained for cleaved caspase-3 using ImageJ. Error bars represent standard deviations (SD) (n = 4). Veh, vehicle. (D) An immunoblot of apoptotic markers in WT and GADD34^−/− MEFs 30 h after Tm (2 μg/ml) treatment is shown. (E) RNA was extracted from kidney samples and assayed by qPCR, normalizing against β-actin mRNA. ISR, integrated stress response.