title: Specific tagging of the egress-related osmiophilic bodies in the gametocytes of Plasmodium falciparum.
abstract: BACKGROUND
  Gametocytes, the blood stages responsible for Plasmodium falciparum transmission, contain electron dense organelles, traditionally named osmiophilic bodies, that are believed to be involved in gamete egress from the host cell. In order to provide novel tools in the cellular and molecular studies of osmiophilic body biology, a P. falciparum transgenic line in which these organelles are specifically marked by a reporter protein was produced and characterized.
  
  
  METHODS
  A P. falciparum transgenic line expressing an 80-residue N-terminal fragment of the osmiophilic body protein Pfg377 fused to the reporter protein DsRed, under the control of pfg377 upstream and downstream regulatory regions, was produced.
  
  
  RESULTS
  The transgenic fusion protein is expressed at the appropriate time and stage of sexual differentiation and is trafficked to osmiophilic bodies as the endogenous Pfg377 protein. These results indicate that a relatively small N-terminal portion of Pfg377 is sufficient to target the DsRed reporter to the gametocyte osmiophilic bodies.
  
  
  CONCLUSIONS
  This is the first identification of a P. falciparum aminoacid sequence able to mediate trafficking to such organelles. To fluorescently tag such poorly characterized organelles opens novel avenues in cellular and imaging studies on their biogenesis and on their role in gamete egress.
authors.affiliation: Infectious Diseases Department, Istituto Superiore di Sanità, v.le Regina Elena 299, Rome 00161, Italy.
authors.forename: Anna Rosa
authors.initials: AR
authors.lastname: Sannella
authors.forename: Anna
authors.initials: A
authors.lastname: Olivieri
authors.forename: Lucia
authors.initials: L
authors.lastname: Bertuccini
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Ferrè
authors.forename: Carlo
authors.initials: C
authors.lastname: Severini
authors.forename: Tomasino
authors.initials: T
authors.lastname: Pace
authors.forename: Pietro
authors.initials: P
authors.lastname: Alano
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D004912:Erythrocytes / Q000469:parasitology*; D018703:Founder Effect; D017930:Genes, Reporter; D008018:Life Cycle Stages; D008164:Luminescent Proteins; D016778:Malaria, Falciparum / Q000469:parasitology* / Q000635:transmission; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D015388:Organelles / Q000235:genetics* / Q000648:ultrastructure; D030781:Organisms, Genetically Modified; D010963:Plasmodium falciparum / Q000235:genetics* / Q000648:ultrastructure; D015800:Protozoan Proteins / Q000235:genetics*; D011993:Recombinant Fusion Proteins; D014162:Transfection
chemical_list: D008164:Luminescent Proteins; D015800:Protozoan Proteins; D011993:Recombinant Fusion Proteins; C413663:fluorescent protein 583