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bioRxiv · 10.1101/617571

Interaction of Plasmodium falciparum Casein kinase 1 (PfCK1) with components of host cell protein trafficking machinery.

Batty, M. B.·Schittenhelm, R. B.·Doerig, C.·Garcia-Bustos, J.
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Abstract

During infection, the Plasmodium falciparum casein kinase 1 (PfCK1) is secreted to the extracellular medium and appears on the RBC membrane during trophozoite stage of development. We attempted to identify a mechanism that describes the secretion of PfCK1 and its appearance on the RBC membrane and suspected a mechanism involving multiple host proteins may be utilised. Indeed, we found that the host proteins GTPase-activating protein and Vps9 domain-containing protein (GAPVD1) and Sorting nexin 22 (SNX22), which have described functions in membrane trafficking in higher eukaryotes, consistently co-purify with PfCK1 suggesting the parasite utilises trafficking pathways previously thought to be inactive in RBCs. Further, reciprocal immunoprecipitation experiments with GAPVD1 identified parasite proteins suggestive of a recycling pathway hitherto only described in higher eukaryotes to recycle membrane proteins. Thus, we have identified components of a trafficking pathway involving parasite proteins that act in concert with host proteins which we hypothesise coordinate the trafficking of PfCK1 during infection.

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Batty, M. B., Schittenhelm, R. B., Doerig, C., Garcia-Bustos, J.. 2019-04-24. Interaction of Plasmodium falciparum Casein kinase 1 (PfCK1) with components of host cell protein trafficking machinery.. https://doi.org/10.1101/617571

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