A newly discovered protein export machine in malaria parasites Academic Article uri icon


  • Several hundred malaria parasite proteins are exported beyond an encasing vacuole and into the cytosol of the host erythrocyte, a process that is central to the virulence and viability of the causative Plasmodium species. The trafficking machinery responsible for this export is unknown. Here we identify in Plasmodium falciparum a translocon of exported proteins (PTEX), which is located in the vacuole membrane. The PTEX complex is ATP-powered, and comprises heat shock protein 101 (HSP101; a ClpA/B-like ATPase from the AAA+ superfamily, of a type commonly associated with protein translocons), a novel protein termed PTEX150 and a known parasite protein, exported protein 2 (EXP2). EXP2 is the potential channel, as it is the membrane-associated component of the core PTEX complex. Two other proteins, a new protein PTEX88 and thioredoxin 2 (TRX2), were also identified as PTEX components. As a common portal for numerous crucial processes, this translocon offers a new avenue for therapeutic intervention.


  • de Koning-Ward, Tania F
  • Gilson, Paul R
  • Boddey, Justin A
  • Rug, Melanie
  • Smith, Brian J
  • Papenfuss, Anthony T
  • Sanders, Paul R
  • Lundie, Rachel J
  • Maier, Alexander G
  • Cowman, Alan F
  • Crabb, Brendan S

publication date

  • June 2009

published in