Fig. 4: CPR-6 activity and aging are interrelated.

a, b The alteration of aging by knocking down daf-2 (a) or by bacterial deprivation (b) changes CPR-6 activity patterns in homogenates of day 2 adult worms (n = 3). c skn-1 is needed for the cpr-6 RNAi-mediated protection from Aβ proteotoxicity as the mix of skn-1 RNAi and EV bacteria (red line) and a concurrent knockdown of skn-1 and cpr-6 (dashed red line) similarly enhance the toxicity of Aβ. No such effect was seen when cpr-6 and daf-16 were concomitantly knocked down (dashed green line). d Three independent paralysis assays confirm the requirement of skn-1 for cpr-6 RNAi to counter Aβ proteotoxicity. Bars represent the average daily rates of paralysis in the three replicates ± SEM (n = 3). Statistical test used: unpaired, one-tailed Student’s t-test (*p < 0.05, **p < 0.01, ***p < 0.001). e RNA-seq experiment indicates that the knockdown of cpr-6 results in the elevated expression of 46 genes and reduced expression of 29 genes (log2 ≤ 0.58 or ≥0.58, p-value ≤ 0.05). f A heat map of prominently upregulated and downregulated genes. g The knockdown of swsn-3 by RNAi enhances paralysis of CL2006 worms and a concurrent knockdown of swsn-3 and of cpr-6 prevents cpr-6 RNAi from alleviating Aβ proteotoxicity. Bars represent the average rates of paralysis in the three replicates ± SEM. Statistical test used: unpaired, one-tailed Student’s t-test (*p < 0.05, **p < 0.01, ***p < 0.001). h Cellular localization analysis unveils that most genes whose expression levels are affected by cpr-6 RNAi encode membrane proteins.