Proteomic interactions between the parasitoid Diachasmimorpha longicaudata and the oriental fruit fly, Bactrocera dorsalis during host parasitism

Abstract

The oriental fruit fly, Bactrocera dorsalis, is an important agricultural pest and biological control is one of the most effective control methodologies. We conducted an investigation on the molecular response of the fruit fly to parasitism by the larval parasitoid, Diachasmimorpha longicaudata using two-dimensional gel electrophoresis and mass spectroscopy. We identified 285 differentially expressed protein spots (109 proteins) during parasitism. The molecular processes affected by parasitism varied at different time point during development. Transferrin and muscle specific protein 20 are the only two proteins differentially expressed that play a role in host immunity 24h after parasitism. Developmental and metabolic proteins from parasitoids (transferrin and enolase) were up-regulated to ensure establishment and early development of parasitoids 48h post parasitism. 72h after parasitism, larval cuticle proteins, transferrin and CREG1 were overexpressed to support the survival of parasitoids while host metabolism proteins and parasitoid regulatory proteins were down-regulated. Host development slowed down while parasitoid development went up at 96h after parasitism. All developmental, regulatory, structural, and metabolic proteins were expressed at their optimum at 120h post parasitism. Host development was reduced, metabolism and regulatory proteins were strongly involved in the activities. The development deteriorated further at 144h after parasitism. Enolase and CREG1 were indicators of parasitoid survival. Hexamerin and transferrin from the parasitoid was peaked at 168–216h after parasitism, strongly indicating that parasitoid would survive. This study represents the first report that reveals the molecular players involved in the interaction between the host and parasitoid.