Evolution of malaria parasite plastid targeting sequences.
The transfer of genes from an endosymbiont to its host typically requires acquisition of targeting signals by the gene product to ensure its return to the endosymbiont for function. Many hundreds of plastid-derived genes must have acquired transit peptides for successful relocation to the nucleus. Here, we explore potential evolutionary origins of plastid transit peptides in the malaria parasite Plasmodium falciparum. We show that exons of the P. falciparum genome could serve as transit peptides after exon shuffling. We further demonstrate that numerous randomized peptides and even whimsical sequences based on English words can also function as transit peptides in vivo. Thus, facile acquisition of transit peptides from existing sequence likely expedited endosymbiont integration through intracellular gene transfer.
Tonkin
Christopher J
CJ
School of Botany, University of Melbourne, Melbourne, Victoria 3010, Australia.
Foth
Bernardo J
BJ
Ralph
Stuart A
SA
Struck
Nicole
N
Cowman
Alan F
AF
McFadden
Geoffrey I
GI
D000595:Amino Acid Sequence; D000818:Animals; D019143:Evolution, Molecular; D005091:Exons / Q000235:genetics; D018503:Genome, Protozoan; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006801:Humans; D008288:Malaria / Q000469:parasitology*; D008969:Molecular Sequence Data; D010271:Parasites / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry; D010963:Plasmodium falciparum / Q000737:chemistry* / Q000166:cytology / Q000235:genetics; D018087:Plastids; D021382:Protein Sorting Signals
D010455:Peptides; D021382:Protein Sorting Signals; D049452:Green Fluorescent Proteins