Pukkila-Worley, ReadFeinbaum, RhondaMcEwan, Deborah L.Conery, AnnieAusubel, Frederick2014-07-072014Pukkila-Worley, Read, Rhonda L. Feinbaum, Deborah L. McEwan, Annie L. Conery, and Frederick M. Ausubel. 2014. “The Evolutionarily Conserved Mediator Subunit MDT-15/MED15 Links Protective Innate Immune Responses and Xenobiotic Detoxification.” PLoS Pathogens 10 (5): e1004143. doi:10.1371/journal.ppat.1004143. http://dx.doi.org/10.1371/journal.ppat.1004143.1553-7366http://nrs.harvard.edu/urn-3:HUL.InstRepos:12406540Metazoans protect themselves from environmental toxins and virulent pathogens through detoxification and immune responses. We previously identified a small molecule xenobiotic toxin that extends survival of Caenorhabditis elegans infected with human bacterial pathogens by activating the conserved p38 MAP kinase PMK-1 host defense pathway. Here we investigate the cellular mechanisms that couple activation of a detoxification response to innate immunity. From an RNAi screen of 1,420 genes expressed in the C. elegans intestine, we identified the conserved Mediator subunit MDT-15/MED15 and 28 other gene inactivations that abrogate the induction of PMK-1-dependent immune effectors by this small molecule. We demonstrate that MDT-15/MED15 is required for the xenobiotic-induced expression of p38 MAP kinase PMK-1-dependent immune genes and protection from Pseudomonas aeruginosa infection. We also show that MDT-15 controls the induction of detoxification genes and functions to protect the host from bacteria-derived phenazine toxins. These data define a central role for MDT-15/MED15 in the coordination of xenobiotic detoxification and innate immune responses.en-USBiology and Life SciencesImmunologyImmune SystemInnate Immune SystemImmunityMicrobiologyOrganismsAnimalsInvertebratesNematodaCaenorhabditisCaenorhabditis ElegansMedicine and Health SciencesInfectious DiseasesBacterial DiseasesPseudomonas InfectionsPathology and Laboratory MedicinePathogenesisHost-Pathogen InteractionsModel OrganismsAnimal ModelsJournal Article2014-07-0710.1371/journal.ppat.1004143