Plasmodium sporozoites require the protein B9 to invade hepatocytes

Priyanka Fernandes (1) , Manon Loubens (1) , Carine Marinach (1) , Romain Coppe , Ludivine Baron (1) , Morgane Grand (1) , Thanh-Phuc Andre (1) , Soumia Hamada (1, 2, 3) , Anne-Claire Langlois (1) , Sylvie Briquet (1) , Philippe Bun (4) , Olivier Silvie (1)

1 CIMI - Centre d'Immunologie et des Maladies Infectieuses
2 PASS-CYPS - Cytométrie Pitié-Salpêtrière
3 PASS-P3S - Plateforme Post-génomique de la Pitié-Salpêtrière
4 IPNP - U1266 Inserm - Institut de psychiatrie et neurosciences de Paris

Plasmodium sporozoites are transmitted to a mammalian host during blood feeding by an infected mosquito and invade hepatocytes for initial replication of the parasite into thousands of erythrocyte-invasive merozoites. Here we report that the B9 protein, a member of the 6-cysteine domain protein family, is secreted from sporozoite micronemes and is required for productive invasion of hepatocytes. The N-terminus of B9 forms a beta-propeller domain structurally related to CyRPA, a cysteine-rich protein forming an essential invasion complex in Plasmodium falciparum merozoites. The beta-propeller domain of B9 is essential for sporozoite infectivity and interacts with the 6-cysteine proteins P36 and P52 in a heterologous expression system. Our results suggest that, despite using distinct sets of parasite and host entry factors, Plasmodium sporozoites and merozoites may share common structural modules to assemble protein complexes for invasion of host cells.

Domaines: Parasitologie; Maladies infectieuses

Priyanka Fernandes, Manon Loubens, Carine Marinach, Romain Coppe, Ludivine Baron, et al.. Plasmodium sporozoites require the protein B9 to invade hepatocytes. iScience, 2023, 26 (2), pp.106056. ⟨10.1016/j.isci.2023.106056⟩. ⟨hal-03987907⟩