<p>A forward genetic screen revealed that <i>egl-2(G574E)</i> mutants are defective in sleep.</p>

A G-to-A point mutation (highlighted in the red box) is identified in the <i>egl-2</i> coding sequence of the <i>sy985</i> allele, resulting in a glycine-to-glutamic acid substitution at position 574 (G574E). (<b>C-D</b>) Quantification of sleep behavior as the fraction of quiescent worms for the indicated genotypes and conditions. All strains contain the transgene (HS::EGF) for conditional overexpression of EGF via 15-min heat shock (HS) at 33 °C to induce sleep.

Pre and post refer to before and 2 h after heat shock, respectively. Each dot represents one independent assay containing 15–25 animals on a single plate. Mean ± SEM are shown. ns, not significant; ****, p < 0.0001.

One-way ANOVA with Dunnett’s multiple-comparisons test for post-heat shock samples, comparing each genotype with wild type. (C) gDNA rescue 1 and 2 are two independent extrachromosomal arrays carrying the same fosmid containing the wild-type <i>egl-2</i> genomic sequence. (D) <i>egl-2(tan200)</i> is a CRISPR-generated allele carrying the same G574E substitution as <i>egl-2(sy985)</i>.

(<b>E</b>) Time course of endogenous stress-induced sleep in animals of the indicated genotypes, shown as the fraction of quiescent worms at each time point. Pre refers to before heat shock. N2 and <i>egl-2(tan200)</i> animals were used as wild type and <i>egl-2(G574E)</i>, respectively.

Data were collected from three independent replicates, with 15–25 animals of each strain assayed on separate plates in each replicate. Mean ± SEM are shown. ns, not significant; *, p < 0.05; **, p < 0.001. Two-tailed unpaired Student’s t-test for comparing wild type with <i>egl-2(tan200)</i> mutants at each time point.</p>