N-acylethanolamines are an important class of lipid signaling molecules found in many species, including the nematode Caenorhabditis elegans (C. elegans) where they are involved in development and adult lifespan. In mammals, the relative activity of the biosynthetic enzyme N-acyl phosphatidylethanolamine-specific phospholipase-D and the hydrolytic enzyme fatty acid amide hydrolase determine N-acylethanolamine levels. C. elegans has two N-acyl phosphatidylethanolamine-specific phospholipase-D orthologs,
nape-1 and
nape-2, that are likely to have arisen from a gene duplication event. Here, we find that recombinant C. elegans NAPE-1 and NAPE-2 are capable of generating N-acylethanolamines in vitro, confirming their functional conservation. In vivo, they exhibit overlapping expression in the pharynx and the nervous system, but are also expressed discretely in these and other tissues, suggesting divergent roles. Indeed,
nape-1 over-expression results in delayed growth and shortened lifespan only at 25C, while
nape-2 over-expression results in significant larval arrest and increased adult lifespan at 15C. Interestingly, deletion of the N-acylethanolamine degradation enzyme
faah-1 exacerbates
nape-1 over-expression phenotypes, but suppresses the larval arrest phenotype of
nape-2 over-expression, suggesting that
faah-1 is coupled to
nape-2, but not
nape-1, in a negative feedback loop. We also find that over-expression of either
nape-1 or
nape-2 significantly enhances recovery from the dauer larval stage in the insulin signaling mutant
daf-2(
e1368), but only
nape-1 over-expression reduces
daf-2 adult lifespan, consistent with increased levels of the N-acylethanolamine eicosapentaenoyl ethanolamine. These results provide evidence that N-acylethanolamine biosynthetic enzymes in C. elegans have conserved function and suggest a temperature-dependent, functional divergence between the two isoforms.