A novel protein export machine in malaria parasites

Several hundred malaria parasite proteins are exported beyond an encasing vacuole and into the cytosol of the host erythrocyte, a process that is key to the virulence and viability of the causative Plasmodium species. The trafficking machinery responsible for this export is unknown. Here, we identify a Plasmodium Translocon of EXported proteins (PTEX), which is located in the vacuole membrane. The PTEX complex is ATP-powered and comprises HSP101, which is a ClpA/B-like AAA+ ATPase of a type commonly associated with protein translocons, a novel protein termed PTEX150 and a known parasite protein EXP2. EXP2 is the potential channel as it is the membrane-associated component of the core PTEX complex. Two other proteins, a novel protein PTEX88 and a thioredoxin known as TRX2, were also identified as PTEX components. As a common portal for numerous crucial processes, this novel translocon offers an exciting new avenue for therapeutic intervention.