6533b7d2fe1ef96bd125f4e8
RESEARCH PRODUCT
Global Functional Analyses of Cellular Responses to Pore-Forming Toxins
Chih-shen HsuLi ChenRaffi V. AroianShinichiro WachiFerdinand C. O. LosAudrey BellierJean-louis SchwartzMindy HsiehDanielle L. HuffmanCheng Yuan KaoMatthias HusmannChristine HaValbona KarabrahimiNicole KloftHui FanYoun SagongPartho Ghoshsubject
MAPK/ERK pathwayTranscription GeneticImmunology/Innate ImmunityMessengerInteractomeInfectious Diseases/Bacterial InfectionsRNA interference2.1 Biological and endogenous factorsAetiologyBiology (General)Genes HelminthCaenorhabditis elegansOligonucleotide Array Sequence AnalysisGenetics0303 health sciencesGenomebiologyReverse Transcriptase Polymerase Chain ReactionGenetics and Genomics/Functional Genomics030302 biochemistry & molecular biologyrespiratory systemCell biologyInfectious DiseasesMedical MicrobiologyRNA InterferenceSignal transductionDNA microarrayTranscriptionBiotechnologyResearch ArticleSignal TransductionPore Forming Cytotoxic ProteinsQH301-705.5Virulence FactorsMAP Kinase Signaling System1.1 Normal biological development and functioningBacterial ToxinsImmunologyMicrobiologyDNA-binding proteinCell Line03 medical and health sciencesBacterial ProteinsGeneticUnderpinning researchVirologyEscherichia coliHelminthGeneticsAnimalsHumansRNA MessengerCaenorhabditis elegansCaenorhabditis elegans ProteinsMolecular BiologyGene030304 developmental biologyGenome HelminthCell MembraneGenetics and GenomicsRC581-607biology.organism_classificationrespiratory tract diseasesTranscription Factor AP-1Emerging Infectious DiseasesGenesRNAParasitologyGeneric health relevanceRNA HelminthImmunologic diseases. Allergydescription
Here we present the first global functional analysis of cellular responses to pore-forming toxins (PFTs). PFTs are uniquely important bacterial virulence factors, comprising the single largest class of bacterial protein toxins and being important for the pathogenesis in humans of many Gram positive and Gram negative bacteria. Their mode of action is deceptively simple, poking holes in the plasma membrane of cells. The scattered studies to date of PFT-host cell interactions indicate a handful of genes are involved in cellular defenses to PFTs. How many genes are involved in cellular defenses against PFTs and how cellular defenses are coordinated are unknown. To address these questions, we performed the first genome-wide RNA interference (RNAi) screen for genes that, when knocked down, result in hypersensitivity to a PFT. This screen identifies 106 genes (∼0.5% of genome) in seven functional groups that protect Caenorhabditis elegans from PFT attack. Interactome analyses of these 106 genes suggest that two previously identified mitogen-activated protein kinase (MAPK) pathways, one (p38) studied in detail and the other (JNK) not, form a core PFT defense network. Additional microarray, real-time PCR, and functional studies reveal that the JNK MAPK pathway, but not the p38 MAPK pathway, is a key central regulator of PFT-induced transcriptional and functional responses. We find C. elegans activator protein 1 (AP-1; c-jun, c-fos) is a downstream target of the JNK-mediated PFT protection pathway, protects C. elegans against both small-pore and large-pore PFTs and protects human cells against a large-pore PFT. This in vivo RNAi genomic study of PFT responses proves that cellular commitment to PFT defenses is enormous, demonstrates the JNK MAPK pathway as a key regulator of transcriptionally-induced PFT defenses, and identifies AP-1 as the first cellular component broadly important for defense against large- and small-pore PFTs.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2011-03-01 | PLoS Pathogens |