Natural Genetic Variation in theCaenorhabditis elegansResponse toPseudomonas aeruginosa.
Caenorhabditis elegansresponds to pathogenic microorganisms by activating its innate immune system, which consists of physical barriers, behavioral responses, and microbial killing mechanisms. We examined whether natural variation plays a role in the response ofC. eleganstoPseudomonas aeruginosausing twoC. elegansstrains that carry the same allele ofnpr-1, a gene that encodes a G-protein-coupled receptor related to mammalian neuropeptide Y receptors, but that differ in their genetic backgrounds. Strains carrying an allele for the NPR-1 215F isoform have been shown to exhibit lack of pathogen avoidance behavior and deficient immune response towardP. aeruginosarelative to the wild-type (N2) strain. We found that the wild isolate from Germany RC301, which carries the allele for NPR-1 215F, shows an enhanced resistance toP. aeruginosainfection when compared with strain DA650, which also carries NPR-1 215F but in an N2 background. Using a whole-genome sequencing single-nucleotide polymorphism (WGS-SNP) mapping strategy, we determined that the resistance toP. aeruginosainfection maps to a region on chromosome V. Furthermore, we demonstrated that the mechanism for the enhanced resistance toP. aeruginosainfection relies exclusively on strongP. aeruginosaavoidance behavior, and does not involve the main immune, stress, and lifespan extension pathways inC. elegansOur findings underscore the importance of pathogen-specific behavioral immune defense in the wild, which seems to be favored over the more energy-costly mechanism of activation of physiological cellular defenses.
Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina 27710.|Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan 48824.
Natalia
N
Martin
Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina 27710.
Jogender
J
Singh
Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina 27710 a.aballay@duke.edu.
Alejandro
A
Aballay
D000818:Animals; D001522:Behavior, Animal; D017173:Caenorhabditis elegans / Q000235:genetics* / Q000276:immunology / Q000302:isolation & purification / Q000382:microbiology*; D029742:Caenorhabditis elegans Proteins / Q000378:metabolism; D002874:Chromosome Mapping; D002875:Chromosomes / Q000235:genetics; D016153:Genes, Suppressor; D056726:Genetic Association Studies; D014644:Genetic Variation; D000073658:Loss of Function Mutation / Q000235:genetics; D009474:Neurons / Q000378:metabolism; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D011550:Pseudomonas aeruginosa / Q000502:physiology*; D034622:RNA Interference; D017476:Receptors, Neuropeptide Y / Q000378:metabolism; D000073336:Whole Genome Sequencing
D029742:Caenorhabditis elegans Proteins; C468272:NPR-1 protein, C elegans; D017476:Receptors, Neuropeptide Y
Pseudomonas aeruginosa; bacterial infection; innate immunity; pathogen avoidance; wild isolate