Fig. 3

XRCC1 KD induces the integrated stress response through PERK to support survival under nutrient-restricted conditions. a–d Representative Western blots of a ATF4 and XRCC1 levels after siXRCC1. The band specific for ATF4 is indicated with a dash. n = 3. b peIF2α after siXRCC1 or Thapsigargin. Normalised peIF2α levels are shown below the lanes. n = 3. c ATF4 and XRCC1 after KD of XRCC1 and/or GCN2. The band specific for ATF4 is indicated with a dash. Normalised levels of ATF4 are shown below the lanes. n = 3. d PERK and ATF4 after KD of XRCC1 and/or PERK. The band specific for ATF4 is indicated with a dash. Normalised levels of ATF4 are shown below the lanes. n = 3. e–h Phase-contrast images of cells treated with e siControl, f siXRCC1, g siPERK, or h siXRCC1 and siPERK, and grown in medium containing 1% FCS. Images are from one representative experiment with four different fields randomly chosen per condition. Scale bar = 400 μm. i Quantification of relative cell area as shown in e–h, normalised to siControl grown at 1% FCS. n = 4. Only statistically significant differences are indicated using asterisks