The expression of cytoskeletal binding proteins KAHRP is increased in ΔHsp70-x. (a) Immuno fluorescence microscopy of 16-24 hpi parasites indicates expression of the exported, knob localized KAHRP protein but not RESA appears higher in ΔHsp70-x. Antibodies to the cytoskeletal binding proteins ring exported surface antigen (RESA) and knob associated histidine rich protein (KAHRP) indicated the MFI was significantly higher for KAHRP but not RESA in the mutant. The CS2 parasite line in which the ΔHsp70-x clones were derived from stably expresses the single VAR2CSA PfEMP1 allele, which binds to chondroitin sulfate A (CSA) normally present in the placenta.

Charnaud SC, Dixon MWA, Nie CQ, Chappell L, Sanders PR, Nebl T, Hanssen E, Berriman M, Chan JA, Blanch AJ, Beeson JG, Rayner JC, Przyborski JM, Tilley L, Crabb BS, Gilson PR. The exported chaperone Hsp70-x supports virulence functions for Plasmodium falciparum blood stage parasites. PLoS One. 2017 12(7):e0181656.