Figure 1. ALG-1 and ALG-2 Are Linked to Stress Resistance and Proteostasis: (A) Schematic overview on the microRNA pathway in C. elegans. (B), (C) The Argonaute-family members ALG-1 and ALG-2 are required for resistance against oxidative (B) and heat stress (C) compared to wild-type (WT) worms. Data show mean values ± SEM obtained from n = 3 independent experiments using 100-250 worms for paraquat and 50-100 worms for heat stress treatment; *p < 0.05, ***p < 0.001; one-way ANOVA with post-hoc test. (D) alg
x2011;1
(gk214) and
alg-2(
ok304) deletion mutants exhibit short lifespans. Data obtained from n = 2 independent experiments; median lifespan (mean values ± SEM): WT (18.5 ± 0.5 days),
alg-1(
gk214) (9 ± 0.0 days),
alg-2(
ok304) (15 ± 0.0 days). Significance was determined using the Log-rank (Mantel-Cox) test; < 0.0001. (E) The ubiquitin fusion degradation (UFD) model substrate monitors ubiquitin-dependent degradation. (F, G) RNAi-mediated depletion of
alg-1 and
alg-2 (F) and the
alg-1(
gk214) and
alg-2(
ok304) deletion alleles (G) exhibit UFD substrate stabilization. Representative western blots of worm lysates with indicated RNAi and genotypes detecting the UFD substrate (UbV-GFP) and tubulin (TUB). (H) The CPL-1*-YFP model substrate monitors ER-associated protein degradation (ERAD). (I, J) RNAi-mediated depletion of
alg-2 (I) and the
alg-2(
ok304) deletion allele (J) exhibit increased ERAD substrate level. Representative western blots of worm lysates with indicated RNAi and genotypes showing CPL-1*-YFP and tubulin (TUB) level.