skr-1/2 are required for the extended lifespan of daf-2 mutants but not other long-lived mutants or wild-type worms. Lifespan experiments of long-lived mutants and wild-type worms grown as adults on control empty vector (green lines), daf-16 RNAi (blue lines), skr-1 RNAi (deep red lines), and skr-2 RNAi (bright red lines). (A) daf-2(mu150). Control vector: mean = 33.4 ± 0.7, n = 89/90; daf-16 RNAi: mean = 17.3 ± 0.5, n = 80/83, P < 0.0001 vs. control; skr-1 RNAi: mean = 22.0 ± 0.5, n = 88/91, P < 0.0001 vs. control; skr-2 RNAi: mean = 22.8 ± 0.4, n = 92/92, P < 0.0001 vs. control. (B) N2. Control vector: mean = 20.7 ± 0.7, n = 67/88; daf-16 RNAi: mean = 16.6 ± 0.5, n = 67/87, P < 0.0001 vs. control; skr-1 RNAi: mean = 20.7 ± 0.7, n = 82/86, P = 0.71 vs. control; skr-2 RNAi: mean = 21.4 ± 0.9, n = 67/81, P = 0.19 vs. control. (C) glp-1(e2141ts). Control vector: mean = 22.4 ± 1.0, n = 82/85; daf-16 RNAi: mean = 16.1 ± 0.3, n = 88/88, P < 0.0001 vs. control; skr-1 RNAi: mean = 21.8 ± 0.8, n = 88/91, P = 0.19 vs. control; skr-2 RNAi: mean = 22.1 ± 0.7, n = 92/92, P = 0.1 vs. control. (D) eat-2(ad1116). Control vector: mean = 27.3 ± 0.6, n = 70/96; skr-1 RNAi: mean = 23.8 ± 1.1, n = 66/94, P = 0.2 vs. control; skr-2 RNAi: mean = 27.3 ± 0.6, n = 67/93, P = 0.8 vs. control.