Analysis of Ca2 mediated signaling regulating Toxoplasma infectivity reveals complex relationships between key molecules

Abstract

Host cell invasion, exit and parasite dissemination is critical to the pathogenesis of apicomplexan parasites such as Toxoplasma gondii and Plasmodium spp. These processes are regulated by intracellular Ca2 + signaling although the temporal dynamics of Ca2 + fluxes and down-stream second messenger pathways are poorly understood. Here, we use a genetically encoded biosensor, GFP-Calmodulin-M13–6 (GCaMP6), to capture Ca2 + flux in live Toxoplasma and investigate the role of Ca2 + signaling in egress and motility. Our analysis determines how environmental cues and signal activation influence intracellular Ca2 + flux, allowing placement of effector molecules within this pathway. Importantly, we ..