Mitochondrial UPR repression during Pseudomonas aeruginosa infection requires the bZIP protein ZIP-3

Significance Mitochondria are the compartments in animal cells that produce the most energy and are often targets of bacterial toxins during infection. In response, hosts employ an adaptive transcriptional response known as the mitochondrial unfolded protein response (UPRmt ) to maintain mitochondrial function and eliminate the toxic bacteria. Here, we demonstrate that the pathogenPseudomonas aeruginosa exploits a negative regulatory mechanism built into the UPRmt to prevent activation of the antibacterial response. Impressively, if the negative regulator ZIP-3 is inhibited, worms are resistant to infection as they are able to effectively activate the UPRmt . The pathogen potentially evolved means to impair the UPRmt because a virulence determinant that ordinarily maintains biofilm metabolism perturbs mitochondrial function eliciting the antibacterial response.