Genetic Screen Reveals Link between the Maternal Effect Sterile Gene mes-1 and Pseudomonas aeruginosa-induced Neurodegeneration in Caenorhabditis elegans

Increasing evidence indicates that immune responses to microbial infections may contribute to neurodegenerative diseases. Here, we show that Pseudomonas aeruginosa infection of Caenorhabditis elegans causes a number of neural changes that are hallmarks of neurodegeneration. Using an unbiased genetic screen to identify genes involved in the control of P. aeruginosa-induced neurodegeneration, we identified mes-1, which encodes a receptor tyrosine kinase-like protein that is required for unequal cell divisions in the early embryonic germ line. We showed that sterile but not fertile mes-1 animals were resistant to neurodegeneration induced by P. aeruginosa infection. Similar results were observed using animals carrying a mutation in the maternal effect gene pgl-1, which is required for postembryonic germ line development, and the germ line-deficient strains glp-1 and glp-4. Additional studies indicated that the FOXO transcription factor DAF-16 is required for resistance to P. aeruginosa-induced neurodegeneration in germ line-deficient strains. Thus, our results demonstrate that P. aeruginosa infection results in neurodegeneration phenotypes in C. elegans that are controlled by the germ line in a cell-nonautonomous manner.