Floria Uy Seminar

Prolonged coevolution between hosts and parasites can generate novel and complex host phenotypes. Intriguingly, neuroplasticity, intended to provide advantages to hosts, can instead be exploited to enable rapid phenotypic change that benefits the parasite. They leveraged the parasitic insect Xenos peckii  (Strepsiptera), which infects the social wasp Polistes fuscatus to elucidate how traits can be decoupled to generate an extended phenotype. Both parasite sexes inhibit reproduction and manipulate the social behavior of female workers, but not of male hosts that do not have castes. In addition, only adult female X. peckii remain as obligate endoparasites and extend the lifespan of workers, but not of male wasps. Therefore, her group hypothesizes that the parasite controls plasticity that mediates caste-related traits that are critical for parasite survival and fitness. They first utilized a time series of females hosts that revealed how parasites manipulate key genes in the developing brain of hosts. Second, multi-omic signatures of infected adult brains showed similarities with uninfected gyne brains, highlighting pathways shown to regulate longevity, reproduction, diapause, and neuromodulation. However, parasites cannot effectively manipulate some of these traits in male hosts, which supports their main hypothesis. Together, their results reveal novel insights about how plasticity facilitates reprogramming female wasps into an extended phenotype that decouples behavior, reproduction, and lifespan.