Gene expression profiling of undertaking behavior in the eastern subterranean termite, Reticulitermes flavipes

Undertaking behavior is the disposal of dead individuals in social colonies to prevent potential pathogenic attack, and considered an essential adaptation to social living. However, the molecular basis of undertaking behavior remains unknown. In the eastern subterranean termite, Reticulitermes flavipes, workers exhibited differential responses toward corpse with different postmortem time and origin. Specifically, workers cannibalized freshly dead nestmates, but buried decayed nestmates as well as corpses of a competitive species, R. malletei. Using RNA-Seq analysis, we surveyed the molecular signatures underlying the three types of undertaking process. Differentially expressed genes (DEGs) in workers with or without corpses were analyzed and functionally annotated using Gene Ontology and KEGG pathway analysis. Our results showed that different sets of DEGs were associated with each type of undertaking response, suggesting that different gene networks are involved in corpse cannibalism, burial of dead nestmates, and burial of dead competitors. This study is the first to investigate the molecular basis underlying undertaking behavior, a convergently evolved trait in social insects including honeybee, ants and termites. These findings advance our understanding of social behavior in termites, and provides candidate molecular targets for the control of this wood-feeding insect pest.