Fig. 2.

Components of the Plasmodium glideosome identified in sporozoite stages. The currently known components of Plasmodium's gliding motility and invasion machinery (the “glideosome”) mainly identified from asexual blood stages and orthologs from Toxoplasma gondii are illustrated in this model and are depicted based on their presence in the sporozoite proteome. Sporozoite proteins are colored to indicated whether they were detected in P. falciparum sporozoites only (red), P. yoelii sporozoites only (yellow), both species (orange), or neither species (gray). Two shades of orange were used to provide contrast between the intertwined tubulin and F-actin molecules. The anchoring of CSP in the sporozoite plasma membrane occurs via a glycosylphosphatidylinositol anchor, whereas invasins do so via a transmembrane domain and a cytoplasmic C-terminal tail that interacts with aldolase through a conserved penultimate tryptophan (this interaction for Thrombospondin Related Anonymous Protein (TRAP)-related protein has not been experimentally validated and is indicated by a question mark). Aldolase 2 and Actin 2 were previously thought to be present only in blood stage parasites but were confidently identified in these experiments. They are marked with question marks, as their involvement in gliding motility has not been experimentally validated.