Isolation and Characterization of High-Temperature-Induced Dauer Formation Mutants in Caenorhabditis elegans

Dauer formation in Caenorhabditis elegans is regulated by at least three signaling pathways, including an insulin receptorsignaling pathway. These pathways were defined by mutants that form dauers constitutively (Daf-c) at 25. Screens for Daf-c mutants at 25 have probably been saturated, but failed to identify all the components involved in regulating dauer formation. Here we screen for Daf-c mutants at 27, a more strongly dauer-inducing condition. Mutations identified include novel classes of alleles for three known genes and alleles defining at least seven new genes, hid-1–hid-7. Many of the genes appear to act in the insulin branch of the dauer pathway, including pdk-1, akt-1, aex-6, and hid-1. We also molecularly identify hid-1 and show that it encodes a novel highly conserved putative transmembrane protein expressed in neurons.