Authors

Discussion

Rosetting, the binding of P. falciparum infected erythrocytes to uninfected erythrocytes to form clusters (rosettes), is thought to contribute to severe malaria. This adhesion phenotype is mediated through the adhesive properties of P. falciparum erythrocyte membrane protein 1 (PfEMP1), encoded by the var gene family (~60 distinct copies per parasite genome expressed in a mutually exclusive manner). The N-terminal domain (NTS-DBLα) of PfEMP1 has been implicated as the functional erythrocyte binding domain. However, the role of PfEMP1 in adhesion in live infected erythrocytes remains poorly understood, mainly due to the difficulty in genetically manipulating P. falciparum. Here, we aim to test a strategy to generate a population of parasites expressing a single var gene and use CRISPR-Cas9 genome editing technology to investigate whether specific motifs within DBLα of the rosetting PfEMP1 variant “IT4var60” are sufficient to mediate the rosetting phenotype in P. falciparum. We have shown that a var gene co-expressed with a drug resistance gene via 2A peptide can be inducibly and exclusively expressed under drug pressure. Presently, we are generating transgenic parasites to test the role of specific PfEMP1 domains/motifs/residues in rosette formation. This work has potential to contribute to the rational design of anti-rosetting interventions, with the ultimate goal of reducing deaths from severe malaria.