1. An aspartyl protease directs malaria effector proteins to the host cell.
- Author
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Boddey JA, Hodder AN, Günther S, Gilson PR, Patsiouras H, Kapp EA, Pearce JA, de Koning-Ward TF, Simpson RJ, Crabb BS, and Cowman AF
- Subjects
- Amino Acid Motifs, Animals, Antimalarials pharmacology, Aspartic Acid Endopeptidases genetics, Aspartic Acid Endopeptidases isolation & purification, Endoplasmic Reticulum enzymology, Endoplasmic Reticulum metabolism, Erythrocytes cytology, Erythrocytes parasitology, HIV Protease Inhibitors pharmacology, Humans, Malaria, Falciparum metabolism, Malaria, Falciparum pathology, Plasmodium falciparum enzymology, Plasmodium falciparum genetics, Protein Processing, Post-Translational drug effects, Protein Transport, Protozoan Proteins chemistry, Aspartic Acid Endopeptidases metabolism, Erythrocytes metabolism, Malaria, Falciparum blood, Malaria, Falciparum parasitology, Plasmodium falciparum metabolism, Protein Sorting Signals, Protozoan Proteins metabolism
- Abstract
Plasmodium falciparum causes the virulent form of malaria and disease manifestations are linked to growth inside infected erythrocytes. To survive and evade host responses the parasite remodels the erythrocyte by exporting several hundred effector proteins beyond the surrounding parasitophorous vacuole membrane. A feature of exported proteins is a pentameric motif (RxLxE/Q/D) that is a substrate for an unknown protease. Here we show that the protein responsible for cleavage of this motif is plasmepsin V (PMV), an aspartic acid protease located in the endoplasmic reticulum. PMV cleavage reveals the export signal (xE/Q/D) at the amino terminus of cargo proteins. Expression of an identical mature protein with xQ at the N terminus generated by signal peptidase was not exported, demonstrating that PMV activity is essential and linked with other key export events. Identification of the protease responsible for export into erythrocytes provides a novel target for therapeutic intervention against this devastating disease.
- Published
- 2010
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