Fig. 1: daf-18(yh1) suppresses developmental defects with minimal effects on longevity and resistance against various stresses in daf-2(−) mutants.

a Schematic of forward genetic screen for fitness-regulating factors in daf-2(e1370) [daf-2(−)] mutants. Synchronized P₀ daf-2(−) animals were treated with ethyl methanesulfonate (EMS) to obtain > 3 million F₁ worms. The F₂ eggs were then transferred to OP50-seeded NGM plates and cultured at 25 °C for screening dauer suppressors. The dauer-suppressor mutants were immediately placed on plates seeded with pathogenic bacteria, Pseudomonas aeruginosa (PA14), for screening pathogen-resistant worms compared with daf-16(mu86) [daf-16(−)]; daf-2(−) mutants. When all the daf-16(−); daf-2(−) animals died but daf-2(−) animals were still alive, each of fertile survivors was singled and used for genetic analysis in this study (see Methods for details). b, c mCherry::daf-18 fully rescued dauer formation (n ≥ 433 for each condition, from two independent trials) (b) and the increased survival of worms on the pathogenic bacteria PA14 (n ≥ 180 for each condition, with big lawn where worms do not have space for an avoidance behavior) (c) in daf-2(−); daf-18(yh1) mutants to the levels of daf-2(−) animals. d, e Survival curves of outcrossed daf-2(−); daf-18(yh1) and daf-2(−); daf-18(nr2037) [daf-18(−)] mutants on PA14 big lawn (n = 180 for each condition) (d) and PA14 small lawn where worms can avoid the pathogen (n ≥ 180 for each condition) (e), compared with daf-2(−) and wild-type (WT) worms. f Representative images of indicated animals, WT, daf-2(−); daf-18(+), daf-2(−); daf-18(yh1), daf-2(−); daf-18(syb499), and daf-2(−); daf-18(−), after PA14-GFP exposure. Scale bar: 50 μm. g Quantification of PA14-GFP levels in the intestinal lumen of worms in (f) (n ≥ 25 for each condition, from three independent trials). Error bars represent the standard error of the mean (s.e.m., ***p < 0.001, n.s.: not significant, chi-squared test relative to WT). h Feeding rate of the indicated strains after PA14-GFP infection (n = 30 for each condition, pharyngeal pumping per minute from three independent trials, *p < 0.05, **p < 0.01, ***p < 0.001, n.s.: not significant, two-tailed Student’s t test relative to WT). i–k Lifespan (n ≥ 225 for each condition) (i), oxidative stress resistance (n = 180 for each condition) (j), and thermotolerance (n = 180 for each condition) (k) of WT, daf-2(−), daf-2(−); daf-18(yh1), and daf-2(−); daf-18(−) worms. See Supplementary Dataset 2, 3, and 4 for additional repeats and statistical analysis for the survival assay and fitness data shown in this figure. See also Source Data for data points used for the derivation of data.