The Plasmodium falciparum protein Pfg27 is dispensable for gametocyte and gamete production, but contributes to cell integrity during gametocytogenesis

Mol Microbiol. 2009 Jul;73(2):180-93. doi: 10.1111/j.1365-2958.2009.06762.x. Epub 2009 Jun 30.

Abstract

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aedes / parasitology
  • Animals
  • Antigens, Protozoan / metabolism*
  • DNA, Protozoan / genetics
  • Gene Expression Regulation, Developmental
  • Genes, Protozoan
  • Germ Cells / growth & development*
  • Germ Cells / ultrastructure
  • Plasmodium falciparum / genetics*
  • Plasmodium falciparum / growth & development
  • Plasmodium falciparum / metabolism
  • Plasmodium falciparum / ultrastructure
  • Protozoan Proteins / genetics
  • Protozoan Proteins / metabolism*
  • Sequence Analysis, DNA
  • Transfection

Substances

  • Antigens, Protozoan
  • DNA, Protozoan
  • Protozoan Proteins
  • Pfg25-27 protein, Plasmodium falciparum