Intergenerational Pathogen-Induced Diapause in Caenorhabditis elegans Is Modulated by mir-243

Persistent infection of the bacterivore nematode C. elegans with bac-teria such as P. aeruginosa and S. enterica makes the worm diapause or hibernate.By doing this, the worm closes its mouth, avoiding infection. This response takestwo generations to be implemented. In this work, we looked for genes expressedupon infection that could mediate the worm diapause triggered by pathogens. Weidentify mir-243-3p as the only transcript commonly upregulated when animals feedon P. aeruginosa and S. enterica for two consecutive generations. Moreover, we dem-onstrate that mir-243-3p is required for pathogen-induced dauer formation, a newfunction that has not been previously described for this microRNA (miRNA). We alsofind that the transcriptional activators DAF-16, PQM-1, and CRH-2 are necessary forthe expression of mir-243 under pathogenesis. Here we establish a relationship be-tween a small RNA and a developmental change that ensures the survival of a per-centage of the progeny.