Cryogenic electron tomography reveals novel structures in the apical complex of <i>Plasmodium falciparum</i>

Abstract

Malaria is an infectious disease caused by parasites of the genus <i>Plasmodium</i> and is a leading cause of morbidity and mortality globally. Upon infection, <i>Plasmodium</i> parasites invade and replicate in red blood cells, where they are largely protected from the immune system. To enter host cells, the parasites employ a specialized apparatus at their anterior end. In this study, advanced imaging techniques like cryogenic electron tomography (cryo-ET) and Volta Phase Plate enable unprecedented visualization of whole <i>Plasmodium falciparum</i> merozoites, revealing previously unknown structural details of their invasion machinery. Key findings include new insights into the structural conservation of apical rings shared between <i>Plasmodium</i> and its apicomplexan cousin, <i>Toxoplasma</i>. These discoveries shed light on the essential and conserved elements of the invasion machinery used by these pathogens. Moreover, the research provides a foundation for understanding the molecular mechanisms underlying parasite-host interactions, potentially informing strategies for combating diseases caused by apicomplexan parasites.