title: Identification of rhoptry trafficking determinants and evidence for a novel sorting mechanism in the malaria parasite Plasmodium falciparum.
abstract: The rhoptry of the malaria parasite Plasmodium falciparum is an unusual secretory organelle that is thought to be related to secretory lysosomes in higher eukaryotes. Rhoptries contain an extensive collection of proteins that participate in host cell invasion and in the formation of the parasitophorous vacuole, but little is known about sorting signals required for rhoptry protein targeting. Using green fluorescent protein chimeras and in vitro pull-down assays, we performed an analysis of the signals required for trafficking of the rhoptry protein RAP1. We provide evidence that RAP1 is escorted to the rhoptry via an interaction with the glycosylphosphatidyl inositol-anchored rhoptry protein RAMA. Once within the rhoptry, RAP1 contains distinct signals for localisation within a sub-compartment of the organelle and subsequent transfer to the parasitophorous vacuole after invasion. This is the first detailed description of rhoptry trafficking signals in Plasmodium.
authors.affiliation: The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia.
authors.forename: Dave
authors.initials: D
authors.lastname: Richard
authors.forename: Lev M
authors.initials: LM
authors.lastname: Kats
authors.forename: Christine
authors.initials: C
authors.lastname: Langer
authors.forename: Casilda G
authors.initials: CG
authors.lastname: Black
authors.forename: Khosse
authors.initials: K
authors.lastname: Mitri
authors.forename: Justin A
authors.initials: JA
authors.lastname: Boddey
authors.forename: Alan F
authors.initials: AF
authors.lastname: Cowman
authors.forename: Ross L
authors.initials: RL
authors.lastname: Coppel
mesh_terms: D000818:Animals; D017261:Glycosylphosphatidylinositols / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D007150:Immunohistochemistry; D008954:Models, Biological; D009154:Mutation; D015388:Organelles / Q000378:metabolism; D010963:Plasmodium falciparum / Q000235:genetics / Q000502:physiology*; D021381:Protein Transport / Q000502:physiology*; D015800:Protozoan Proteins / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment
chemical_list: D017261:Glycosylphosphatidylinositols; D015800:Protozoan Proteins; D011993:Recombinant Fusion Proteins; C065352:rhoptry associated protein, Plasmodium; D049452:Green Fluorescent Proteins