title: Dissecting apicoplast targeting in the malaria parasite Plasmodium falciparum.
abstract: Transit peptides mediate protein targeting into plastids and are only poorly understood. We extracted amino acid features from transit peptides that target proteins to the relict plastid (apicoplast) of malaria parasites. Based on these amino acid characteristics, we identified 466 putative apicoplast proteins in the Plasmodium falciparum genome. Altering the specific charge characteristics in a model transit peptide by site-directed mutagenesis severely disrupted organellar targeting in vivo. Similarly, putative Hsp70 (DnaK) binding sites present in the transit peptide proved to be important for correct targeting.
authors.affiliation: Plant Cell Biology Research Centre, School of Botany, University of Melbourne, Parkville, VIC 3010, Australia.
authors.forename: Bernardo J
authors.initials: BJ
authors.lastname: Foth
authors.forename: Stuart A
authors.initials: SA
authors.lastname: Ralph
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Tonkin
authors.forename: Nicole S
authors.initials: NS
authors.lastname: Struck
authors.forename: Martin
authors.initials: M
authors.lastname: Fraunholz
authors.forename: David S
authors.initials: DS
authors.lastname: Roos
authors.forename: Alan F
authors.initials: AF
authors.lastname: Cowman
authors.forename: Geoffrey I
authors.initials: GI
authors.lastname: McFadden
mesh_terms: D000213:Acyl Carrier Protein / Q000378:metabolism; D000465:Algorithms; D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D000596:Amino Acids / Q000032:analysis / Q000737:chemistry; D000818:Animals; D001216:Asparagine / Q000032:analysis; D001665:Binding Sites; D019295:Computational Biology; D049452:Green Fluorescent Proteins; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000378:metabolism; D008164:Luminescent Proteins / Q000378:metabolism; D008239:Lysine / Q000032:analysis; D008954:Models, Biological; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D016571:Neural Networks, Computer; D015388:Organelles / Q000378:metabolism*; D010963:Plasmodium falciparum / Q000378:metabolism*; D011485:Protein Binding; D021382:Protein Sorting Signals; D021381:Protein Transport; D015800:Protozoan Proteins / Q000737:chemistry* / Q000378:metabolism*; D014617:Vacuoles / Q000378:metabolism
chemical_list: D000213:Acyl Carrier Protein; D000596:Amino Acids; D018840:HSP70 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D008164:Luminescent Proteins; D021382:Protein Sorting Signals; D015800:Protozoan Proteins; D049452:Green Fluorescent Proteins; D001216:Asparagine; D008239:Lysine