FLR-4 requires p38 MAPK pathway components to regulate life span.

(A) The flr-4 RNAi increased life span only in WT, but not to the same extent in tir-1(tm3036), unc-43(e408), nsy-1(ag3), nsy-1(ok593), sek-1(km4) or pmk-1(km25) mutants. The percent change in average life span on flr-4 RNAi compared to control RNAi is plotted on the Y-axis. Error bar indicates SEM. ****P≤0.0001, ***P≤0.001, Student’s t test. All life spans were performed at 20 oC. (B) Western blot analysis of young-adult WT or sek-1(km4) grown on control or flr-4 RNAi using anti-phospho-PMK-1, anti-total PMK-1 or anti-β-actin antibodies. Quantification of the blot is shown below. The intensity of pPMK-1 and PMK-1 bands were normalized to beta-actin bands. Percent intensity of pPMK-1 with respect to total PMK is plotted. Average of 4 experiments shown. Error bar indicates SEM. **P≤0.01, *P≤0.05, n.s. not significant, Student’s t test. The activation of p38 MAPK pathway with 20 mM Arsenite was used as a control. Blots from 4 biological replicates available in S14 Fig.