The Maternal Effect of SKN-1B and DAF-7 on Intergenerational Pathogen Avoidance Learning in C. elegans.
Parental health strongly influences the development of embryos, and can ultimately influence behavior post-birth. When exposed to pathogenic Pseudomonas aeruginosa (PA14), C. elegans produces a robust immune response, as well as a learned behavior to avoid PA14 in the future. This learned avoidance of PA14 can be inherited by the F1 generation. An important trigger of the worms immune response to infection is the Nrf2 homologue, SKN-1. We find that the SKN-1B isoform strongly influences the intergenerational inheritance of PA14 avoidance in F1 animals via DAF-7 (TGF-{beta}) signaling from ASI. Functional SKN-1B is required in both the P0 and F1 generations to facilitate F1 avoidance of PA14 due to parental exposure. While inherited avoidance of PA14 was not observed in F2+ generations, the single generation learning investigated here may provide a parallel pathway to improve the fitness of F1 animals in a dynamic environment.