Fig 1: DNAJC5 co-chaperone activity is dispensable for ExoU toxicity.a Domain organization of the human DNAJC5 protein. The following locations are highlighted: the two phosphorylation sites (serine 10 and serine 34), the HPD motif for Hsc70/Hsp70 binding, and the cysteine-rich region containing the leucines L115 and L116, mutated in adult neuronal ceroid lipofuscinosis patients (stars). b Effect of DNAJC5 mutations, H43Q and S10A-S34A, on ExoU toxicity. A549 cells, as well as DNAJC5-/- cells complemented with either DNAJC5, DNAJC5H43Q, DNAJC5S10A-S34A or the empty vector (EV) were subjected to an infection assay with PA14. Data are shown as the mean ± SD. N = 6 fields per condition. c DNAJC5-FLAG (green) and ExoU (red) immunofluorescence signals for DNAJC5-/-::DNAJC5H43Q and DNAJC5-/-::DNAJC5S10A-S34A cells infected with CHA-exoUS142A strain, which secretes a catalytically inactive ExoU mutant. One z-section is shown. For each section, a region was enlarged and an arrow was drawn (represented on the right) to establish the intensity profiles for both green and red fluorescences. d, e. Effect of decreased Hsc70 and Hsp70 expression on ExoU toxicity. A549 cells were transfected with siRNAs for Hsp70 (si_Hsp70) or Hsc70 (si_Hsc70) to knock down their expression. Knockdown was monitored by Western blot (d). KD cells were subjected to an infection assay (e)(n = 5), in the same conditions as in (b). Source data are provided as a Source Data file.