The Plasmodium falciparum protein Pfg27 is dispensable for gametocyte and gamete production, but contributes to cell integrity during gametocytogenesis.
In the human malaria parasite Plasmodium falciparum, gametocyte maturation is a process remarkably longer than in other malaria species, accompanied by expression of 2-300 sexual stage-specific proteins. Disruption of several of their encoding genes so far showed that only the abundant protein Pfg27, produced at the onset of sexual differentiation, is essential for gametocyte production. In contrast with what has been previously described, here we show that P. falciparum pfg27 disruptant lines are able to undergo all stages of gametocyte maturation, and are able to mature into gametes. A fraction of Pfg27-defective gametocytes show, however, distinct abnormalities in intra- and extra-cellular membranous compartments, such as accumulation of parasitophorous vacuole-derived vesicles in the erythrocyte cytoplasm, large intracellular vacuoles and discontinuities in their trilaminar cell membrane. This work revises current knowledge on the role of Pfg27, indicating that the protein is not required for parasite entry into sexual differentiation, and suggesting that it is instead involved in maintaining cell integrity in the uniquely long gametocytogenesis of P. falciparum.
Olivieri
Anna
A
Dipartimento di Malattie Infettive, Parassitarie e Immunomediate, Istituto Superiore di Sanità, 00161, Rome, Italy.
Camarda
Grazia
G
Bertuccini
Lucia
L
van de Vegte-Bolmer
Marga
M
Luty
Adrian J F
AJ
Sauerwein
Robert
R
Alano
Pietro
P
D000330:Aedes / Q000469:parasitology; D000818:Animals; D000953:Antigens, Protozoan / Q000378:metabolism*; D016054:DNA, Protozoan / Q000235:genetics; D018507:Gene Expression Regulation, Developmental; D017125:Genes, Protozoan; D005854:Germ Cells / Q000254:growth & development* / Q000648:ultrastructure; D010963:Plasmodium falciparum / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism / Q000648:ultrastructure; D015800:Protozoan Proteins / Q000235:genetics / Q000378:metabolism*; D017422:Sequence Analysis, DNA; D014162:Transfection
D000953:Antigens, Protozoan; D016054:DNA, Protozoan; D015800:Protozoan Proteins; C069962:Pfg25-27 protein, Plasmodium falciparum