Fig. 5: ER stress mediated increases in PERK transcript occur in a manner partially dependent upon IRE1 RNase signaling.
From: IRE1 signaling increases PERK expression during chronic ER stress
MDA-MB-231 cells were treated with Tg (0.5 μM) (A, B) or cultured under serum deprivation (2.5% serum, 72 h) (C, D) for the indicated timepoints alone or in combination with MKC8866 (MKC, 20 μM). Extracted RNA was utilized for qPCR assessment of relative changes in (A, C) PERK and (B, D) XBP1s transcript. Mean relative expression ± SD, reference gene (A, B) GAPDH and (C, D) RPL10, N = 4. E, F 4T1 cells were treated with Tg (0.5 μM) alone or in combination with MKC8866 (MKC, 20 μM) for 18 h following which RNA was extracted and relative changes in (E) PERK and (F) XBP1s transcript assessed. Mean relative expression ± SD, reference gene RPL13a, N = 4. G, H Scrambled control (SCBL) and XBP1 knockout (XBP1-KO) MDA-MB-231 cells were treated with Tg (0.5 μM) alone or in combination with MKC8866 (MKC, 20 μM) for 18 h after which RNA was extracted and relative expression changes in PERK (G) and XBP1s (H) assessed by qPCR. Mean relative expression ± SD, reference gene GAPDH, N = 4. Statistical significance for all qPCR experiments was determined using one-way ANOVA followed by TUKEY HSD post-hoc analysis. *p ≤ 0.05, **p ≤ 0.01, ***p ≤ 0.001.
