Mechanism of effector protein export by PTEX. Model for PVM translocation mechanism is shown based on the PTEX engaged and resetting states observed by cryoEM. Similar to other HSP100s, pore loops projecting from the HSP101 NBDs interact with cargo in the channel. Conformational changes in the HSP101 hexamer enable these loops to grasp successive portions of the cargo, pull it into the channel, and hold it in place to prevent backsliding. Repeated cycles mediate stepwise unfolding and threading of cargo through HSP101 and across the PVM via the PTEX150 flange-like adaptor and EXP2 membrane-spanning pore. cryoEM, cryo-electron microscopy; EXP2, exported protein 2; HSP101, heat shock protein 101; NBD, nucleotide-binding domain; PTEX, Plasmodium Translocon of EXported proteins; PVM, PV membrane; RBC, red blood cell. Beck JR, Ho CM. Transport mechanisms at the malaria parasite-host cell interface. PLoS Pathog. 2021 17(4):e1009394. PMID: 33793667

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