The transcription factor CHOP, an effector of the integrated stress response, is required for host sensitivity to the fungal intracellular pathogen Histoplasma capsulatum
Fig 2
Hc does not cause ER stress in infected BMDMs.
BMDMs were infected with the indicated Hc strains at an MOI of 5, mock infected (uninf), or treated with 2.5 μg/mL tunicamycin (Tm). (A) Unspliced (Xbp1u) and spliced (Xbp1s) isoforms of Xbp1 were detected by non-quantitative RT-PCR. (B-D) Relative abundances of (B) ERdj4, (C) SEL1L, and (D) BiP were measured by RT-qPCR. (E) Phosphorylated PERK (Thr 980) was detected by Western blot at 12 hpi. (F) BMDMs were treated with the PERK-specific inhibitor GSK2606414 (3 μM) or vehicle (DMSO) for 12 hpi, and caspase-3/7 activity was assessed and normalized to vehicle-treated uninfected cells. Each value is an average of triplicate wells ± standard deviation. **p<0.01, two-tailed t test.