FAT1 and infection: This decrease in the basal levels of activated PMK-1 in fat-3(wa22) animals, as opposed to the complete loss of phosphorylated PMK-1 protein in sek-1(km4) animals, is consistent with the trends indicated by the qRT-PCR analysis, showing that the expression levels of infection-response genes in the fat-3(wa22) mutant were not as low as in the sek-1(km4) mutant (Figure 4A).