Research Centre for Infectious Diseases, School of Biological Sciences, University of Adelaide, Adelaide, 5005, Australia.
Department of Biochemistry and Pharmacology, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Melbourne, VIC, 3010, Australia.
Commun Biol. 2022 Feb 9;5(1):121. doi: 10.1038/s42003-022-03020-9.
Merozoite invasion of host red blood cells (RBCs) is essential for survival of the human malaria parasite Plasmodium falciparum. Proteins involved with RBC binding and invasion are secreted from dual-club shaped organelles at the apical tip of the merozoite called the rhoptries. Here we characterise P. falciparum Cytosolically Exposed Rhoptry Leaflet Interacting protein 2 (PfCERLI2), as a rhoptry bulb protein that is essential for merozoite invasion. Phylogenetic analyses show that cerli2 arose through an ancestral gene duplication of cerli1. We show that PfCERLI2 is essential for blood-stage growth and localises to the cytosolic face of the rhoptry bulb. Inducible knockdown of PfCERLI2 led to a proportion of merozoites failing to invade and was associated with elongation of the rhoptry organelle during merozoite development and inhibition of rhoptry antigen processing. These findings identify PfCERLI2 as a protein that has key roles in rhoptry biology during merozoite invasion.
裂殖子入侵宿主红细胞（RBC）是人类疟原虫生存所必需的。裂殖子顶端的双俱乐部状细胞器（称为顶端泡）分泌参与 RBC 结合和入侵的蛋白质。在这里，我们将疟原虫胞质暴露的顶端泡小叶相互作用蛋白 2（PfCERLI2）描述为裂殖子入侵所必需的顶端泡泡蛋白。系统发育分析表明，cerli2 是通过 cerli1 的祖先基因复制产生的。我们表明 PfCERLI2 对血期生长至关重要，并定位于顶端泡的胞质面。PfCERLI2 的诱导性敲低导致一部分裂殖子无法入侵，并与裂殖子发育过程中顶端泡的伸长以及裂殖子抗原加工的抑制有关。这些发现表明 PfCERLI2 是裂殖子入侵过程中裂殖子生物学的关键蛋白。
