Role of Rabenosyn-5 and Rab5b in host cell cytosol uptake reveals conservation of endosomal transport in malaria parasites.

Vesicular trafficking, including secretion and endocytosis, plays fundamental roles in the unique biology of Plasmodium falciparum blood-stage parasites. Endocytosis of host cell cytosol (HCC) provides nutrients and room for parasite growth and is critical for the action of antimalarial drugs and parasite drug resistance. Previous work showed that PfVPS45 functions in endosomal transport of HCC to the parasite's food vacuole, raising the possibility that malaria parasites possess a canonical endolysosomal system.

Impact of different mutations on Kelch13 protein levels, ART resistance, and fitness cost in parasites.

Unlabelled: Reduced susceptibility to ART, the first-line treatment against malaria, is common in South East Asia (SEA). It is associated with point mutations, mostly in () but also in other genes, like . K13 and its compartment neighbors (KICs), including UBP1, are involved in endocytosis of host cell cytosol.

Gene-by-gene screen of the unknown proteins encoded on Plasmodium falciparum chromosome 3.

Taxon-specific proteins are key determinants defining the biology of all organisms and represent prime drug targets in pathogens. However, lacking comparability with proteins in other lineages makes them particularly difficult to study. In malaria parasites, this is exacerbated by technical limitations.

The ZIP Code of Vesicle Trafficking in Apicomplexa: SEC1/Munc18 and SNARE Proteins.

Apicomplexans are obligate intracellular parasites harboring three sets of unique secretory organelles termed micronemes, rhoptries, and dense granules that are dedicated to the establishment of infection in the host cell. Apicomplexans rely on the endolysosomal system to generate the secretory organelles and to ingest and digest host cell proteins. These parasites also possess a metabolically relevant secondary endosymbiotic organelle, the apicoplast, which relies on vesicular trafficking for correct incorporation of nuclear-encoded proteins into the organelle.

Endocytosis in Plasmodium and Toxoplasma Parasites.

Endocytosis is critical for many functions in eukaryotic cells. Uptake of host cell cytosol, an indispensable endocytic process in malaria blood-stage parasites, has been known for a long time. However, it is only recently that the proteins involved in this process have started to emerge.

A Kelch13-defined endocytosis pathway mediates artemisinin resistance in malaria parasites.

Artemisinin and its derivatives (ARTs) are the frontline drugs against malaria, but resistance is jeopardizing their effectiveness. ART resistance is mediated by mutations in the parasite's Kelch13 protein, but Kelch13 function and its role in resistance remain unclear. In this study, we identified proteins located at a Kelch13-defined compartment.

PfVPS45 Is Required for Host Cell Cytosol Uptake by Malaria Blood Stage Parasites.

During development in human erythrocytes, the malaria parasite Plasmodium falciparum internalizes a large part of the cellular content of the host cell. The internalized cytosol, consisting largely of hemoglobin, is transported to the parasite's food vacuole where it is degraded, providing nutrients and space for growth. This host cell cytosol uptake (HCCU) is crucial for parasite survival but the parasite proteins mediating this process remain obscure.