Export of malaria proteins requires co-translational processing of the PEXEL motif independent of phosphatidylinositol-3-phosphate binding
AuthorBoddey, JA; O'Neill, MT; Lopaticki, S; Carvalho, TG; Hodder, AN; Nebl, T; Wawra, S; van West, P; Ebrahimzadeh, Z; Richard, D; ...
Source TitleNature Communications
University of Melbourne Author/sNEBL, THOMAS; Boddey, Justin; Babon, Jeffrey; Hodder, Anthony; Cowman, Alan; Lopaticki, Sash
AffiliationMedical Biology (W.E.H.I.)
Document TypeJournal Article
CitationsBoddey, J. A., O'Neill, M. T., Lopaticki, S., Carvalho, T. G., Hodder, A. N., Nebl, T., Wawra, S., van West, P., Ebrahimzadeh, Z., Richard, D., Flemming, S., Spielmann, T., Przyborski, J., Babon, J. J. & Cowman, A. F. (2016). Export of malaria proteins requires co-translational processing of the PEXEL motif independent of phosphatidylinositol-3-phosphate binding. NATURE COMMUNICATIONS, 7 (1), https://doi.org/10.1038/ncomms10470.
Access StatusOpen Access
Plasmodium falciparum exports proteins into erythrocytes using the Plasmodium export element (PEXEL) motif, which is cleaved in the endoplasmic reticulum (ER) by plasmepsin V (PMV). A recent study reported that phosphatidylinositol-3-phosphate (PI(3)P) concentrated in the ER binds to PEXEL motifs and is required for export independent of PMV, and that PEXEL motifs are functionally interchangeable with RxLR motifs of oomycete effectors. Here we show that the PEXEL does not bind PI(3)P, and that this lipid is not concentrated in the ER. We find that RxLR motifs cannot mediate export in P. falciparum. Parasites expressing a mutated version of KAHRP, with the PEXEL motif repositioned near the signal sequence, prevented PMV cleavage. This mutant possessed the putative PI(3)P-binding residues but is not exported. Reinstatement of PEXEL to its original location restores processing by PMV and export. These results challenge the PI(3)P hypothesis and provide evidence that PEXEL position is conserved for co-translational processing and export.
- Click on "Export Reference in RIS Format" and choose "open with... Endnote".
- Click on "Export Reference in RIS Format". Login to Refworks, go to References => Import References