Cell-traversal protein for ookinetes and sporozoites (CelTOS) is a conserved protein that is essential for traversal of malaria parasites in both the mosquito vector and human host and is therefore critical for malaria transmission and disease pathogenesis. It specifically binds phosphatidic acid commonly present within the inner leaflet of plasma membranes, and potently disrupts liposomes composed of phosphatidic acid by forming pores. CelTOS resembles class I viral membrane fusion glycoproteins and a bacterial pore-forming toxin with roles in membrane binding and disruption. CelTOS forms an alpha helical dimer that resembles a tuning fork. Structure analysis indicate that it has a distinct structural architecture with two subdomains that independently resemble membrane binding and/or disrupting proteins and could simultaneously act during disruption [1].

1: Malaria parasite CelTOS targets the inner leaflet of cell membranes for pore-dependent disruption. Jimah JR, Salinas ND, Sala-Rabanal M, Jones NG, Sibley LD, Nichols CG, Schlesinger PH, Tolia NH; Elife. 2016; [Epub ahead of print] PMID:27906127