The Florida carpenter ant, Camponotus floridanus, is a social insect with two worker castes that, despite sharing the same genome, are phenotypically distinct: “Major” workers defend the nest, and “minor” workers forage. Because major workers can be experimentally reprogrammed into minor workers, they are a great system to study the underlying epigenetic mechanisms for phenotypic differentiation. Glastad et al. compared gene expression in the brains of reprogramming-capable younger and reprogramming-incapable older major workers, as well as in the brains of major and minor workers during reprogramming. Chromatin repressor CoREST is up-regulated and required during reprogramming to repress major-biased genes, including enzymes that degrade juvenile hormone, which is key for regulating caste specificity. Thus, a chromatin-based mechanism that links transient epigenetic plasticity to long-lasting and complex social behavior has been uncovered.
Mol. Cell 10.1016/j.molcel.2019.10.012 (2019).