The Role of the Hippo-Yorkie Pathway in Caste Development, Determination and Differentiation in Ants

Abstract

The ancient Hippo-Yorkie pathway regulates various processes including tumorigenesis, tissue regeneration, and organ development. While its role in regulating sizing of developing organs is known, its role in coordinating the growth of developmentally plastic traits remains elusive. Ant castes (minor workers and soldiers) are an emerging model for developmental plasticity as environmental variation can generate body- and trait-specific size differences. Here, I show that the Hippo-Yorkie pathway is associated with, and contributes to, growth variation within and across castes in the ant Camponotus floridanus. Using descriptive approaches (transcriptomic analysis and qPCR), I found that there exists inter- and intra-caste variation in the expression of the Hippo-Yorkie pathway suggesting that it is developmentally plastic. Furthermore, I show that pharmacologically inhibiting Hippo results in an increase in size. Overall, these findings illuminate our understanding of how this tumor suppressor network mediates developmental plasticity, facilitating an organism to adapt to a changing environment.