Starvation induces changes in abundance and small RNA cargo of extracellular vesicles released from Plasmodium falciparum infected red blood cells

Abstract

The lethal malaria parasite Plasmodium falciparum needs to constantly respond and adapt to changes within the human host in order to survive and transmit. One such change is composed of nutritional limitation, which is augmented with increased parasite loads and intimately linked to severe disease development. Extracellular vesicles released from infected red blood cells have been proposed as important mediators of disease pathogenesis and intercellular communication but whether important for the parasite response to nutritional availability is unknown. Therefore, we investigated the abundance and small RNA cargo of extracellular vesicles released upon short-term nutritional starvation of P. falciparum in vitro cultures. We show that primarily ring-stage parasite cultures respond to glucose and amino acid deprivation with an increased release of extracellular vesicles. Small RNA sequencing of these extracellular vesicles further revealed human miRNAs and parasitic tRNA fragments as the main constituent biotypes. Short-term starvations led to alterations in the transcriptomic profile, most notably in terms of the over-represented biotypes. These data suggest a potential role for extracellular vesicles released from P. falciparum infected red blood cells in the response to nutritional perturbations, their potential as prognostic biomarkers and point towards an evolutionary conserved role among protozoan parasites.