Figure 4. Enhanced longevity due to germline ablation is the major transcriptional component of increased pathogen resistance of these animals.

In this schematic of microarrays comparisons, each experiment is represented by two parameters - the ablation status and the bacteria fed, while the double arrows show the samples co-hybridized on the same array. In the first experiment E1, 3,335 genes were differentially expressed when germline ablated animals fed on E. coli were compared against un-ablated animals also fed on E. coli. In second experiment, E2, only 244 genes were differentially expressed when ablated animals exposed to S. marcescens were compared against ablated animals exposed only to E. coli, thus indicating that effects of germline ablation are the major transcriptional component towards increased lifespan and pathogen resistance. We also compared these data to transcriptional response of wild-type P. pacificus worms exposed to S. marcescens (experiment E3, 552 genes, AS, RR, II and RJS, unpublished data). Using these data, we calculated the comparison E4 between ablated versus unablated animals, both fed on S. marcescens, and found 2,962 differentially expressed genes.