Research Research summary Communication is intrinsic to life. Molecular exchange is one form of communication employed throughout all forms of life, including eukaryotic unicellular parasites. These organisms depend entirely on their hosts for survival, feeding off of host-acquired nutrients and often reproducing within them. Giardia lamblia and Entamoeba histolytica are two such parasitic species causing giardiasis and entamoebiasis, respectively. These parasites colonize the intestinal tract of practically all vertebrates and in humans, they mainly cause diarrheal disease but may also lead to more permanent tissue and organ damage. Combined, G. lamblia and E. histolytica are responsible for over 300 million cases of diarrheal disease worldwide. It has been known for several years that Giardia and Entamoeba establish infection by releasing specific proteins called virulence factors that help these parasites colonize hosts while modulating the host’s ability to counteract the invasion through the immune system. Although several secreted parasite proteins have been identified, the mechanisms that regulate this important phenomenon are still unknown. For this reason, our lab aims to determine the identity, composition and distribution of the molecular machines that mediate transport of virulence factors from the parasite cell to the host’s environment. Unravelling the nature of these machines may provide novel therapeutic targets while shedding light on unconventional strategies for molecular communication at the host-parasite interface. Research in our laboratory is generously supported by the Swiss National Science Foundation PRIMA granting scheme.