Dense Granule Protein GRA64 Interacts with Host Cell ESCRT Proteins during <i>Toxoplasma gondii</i> Infection
Joshua Mayoral, Rebekah B. Guevara, Yolanda Rivera-Cuevas, Vincent Tu, Tadakimi Tomita, Julia D. Romano, Leslie Gunther-Cummins, Simone Sidoli, Isabelle Coppens, Vern B. Carruthers, Louis M. Weiss
Abstract
Toxoplasma gondii is a widespread foodborne parasite that causes congenital disease and life-threatening complications in immunocompromised individuals. Part of this parasite's success lies in its ability to infect diverse organisms and host cells and to persist as a latent infection within parasite-constructed structures called tissue cysts. In this study, we characterized a protein that is secreted by T. gondii into its parasitophorous vacuole during intracellular infection, which we dub GRA64. On the vacuolar membrane, this protein is exposed to the host cell cytosol and interacts with specific host ESCRT proteins. Parasites lacking the GRA64 protein exhibit ultrastructural changes in tissue cysts during chronic infection. This study lays the foundation for future studies on the mechanics and consequences of host ESCRT-parasite protein interactions.