A Decline in p38 MAPK Signaling Underlies Immunosenescence in Caenorhabditis elegans
(A) Survival of wild type strain N2 maintained on E. coli OP50 plotted as fraction of worms alive versus time. Arrows indicate ages of worms when P. aeruginosa infection was initiated, when reporter gene expression was examined, and/or when total RNA was harvested for microarray analysis. (B) Schematic of P. aeruginosa infection assay. At the indicated ages, subsets of worms from a synchronized population cultured on a lawn of E. coli OP50 were transferred to plates containing a lawn of P. aeruginosa PA14, and their survival was monitored twice daily thereafter.