Transcriptomic analyses of the termite, Cryptotermes secundus, reveal a gene network underlying a long lifespan and high fecundity

Organisms are typically characterized by a trade-off between fecundity and longevity. Notable exceptions are social insects. In insect colonies, the reproducing caste (queens) outlive their non-reproducing nestmate workers by orders of magnitude and realize fecundities and lifespans unparalleled among insects. How this is achieved is not understood. Here, we identified a single module of co-expressed genes that characterized queens in the termite species Cryptotermes secundus. It encompassed genes from all essential pathways known to be involved in life-history regulation in solitary model organisms. By manipulating its endocrine component, we tested the recent hypothesis that re-wiring along the nutrient-sensing/endocrine/fecundity axis can account for the reversal of the fecundity/longevity trade-off in social insect queens. Our data from termites do not support this hypothesis. However, they revealed striking links to social communication that offer new avenues to understand the re-modelling of the fecundity/longevity trade-off in social insects. Lin et al. use transcriptomics in the social termite, Cryptotermes secundus, to investigate potential pathways underlying the long lifespan and high fecundity of insect queens. They find a module of coexpressed genes in queens that is enriched for pathways involved in fecundity, juvenile hormone signaling, and chemical communication. In particular, their results provide molecular evidence that links social communication with the observed longevity and fecundity in termite queens, compared to termite workers.

Automated summary

The study identifies a module of coexpressed genes in termite queens enriched for pathways related to fecundity, juvenile hormone signaling, and chemical communication. The results provide molecular evidence linking social communication with the observed longevity and fecundity in termite queens compared to workers.