Abstract
SUMMARYNeurotransmitter signaling pathways play major roles in both molecular and behavioral defenses against pathogen invasion, shaping the ability of Caenorhabditis elegans to sense and respond to environmental challenges. Given the conservation of neurotransmitter signaling pathways, their understanding may not only provide insights into the neurobiology of C. elegans but also has broader implications for our understanding of neural-immune interactions and host defense mechanisms in higher organisms. In this review, we discussed the literature on various neurotransmitter signaling pathways, including serotonergic, dopaminergic/octopaminergic, GABAergic, and glutamatergic pathways, and how these pathways modulate molecular and behavioral immune defense against pathogens.