Characterization of Pf3D7_0709800, a conserved protein in Plasmodium spp.

The Plasmodium parasite is a unicellular eukaryote that infects erythrocytes and causes malaria, with Plasmodium falciparum being the most virulent species that is transmitted via mosquitoes and infects humans. Many plasmodium proteins are exported from the parasite into the host red blood cell with multiple functions including host cell remodeling, nutrient intake and immune evasion. These exported proteins and protein export mechanisms are a major focus in malaria research. We aim to characterize Pf3D7_0709800, a small protein predicted as an exported protein. Immunofluorescence assays, protease protection assays and differential extraction of membrane proteins were conducted, which indicated that Pf3D7_0709800 is a soluble protein localized in the parasitophorous vacuole (PV), a space between the unique membrane structure enveloping the parasite plasma membrane within the host. Next, CRISPR-Cas9 endogenous tagging of Pf3D7_0709800 with an inducible knockdown system was attempted, but it did not successfully retrieve positively integrated parasite clones. Furthermore, co-immunoprecipitation of Pf3D7_0709800 and mass spectrometry analysis found possible interacting partners of Pf3D7_0709800, and most are exported proteins that passes through translocons in the PV/PVM. PV1, a protein associated with protein export in the PV, was detected as a likely interacting partner of Pf3D7_0709800, indicating Pf3D7_0709800’s role in Plasmodium protein export systems.Bachelor of Science in Biological Science