Subversion of host cellular functions by the apicomplexan parasites

Authors

  • Louise E. Kemp,

    Corresponding author
    • Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
    Search for more papers by this author
  • Masahiro Yamamoto,

    1. Laboratory of Immunoparasitology, Department of Immunoparasitology, WPI Immunology Frontier Research Centre, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
    Search for more papers by this author
  • Dominique Soldati-Favre

    1. Department of Microbiology and Molecular Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland
    Search for more papers by this author

Correspondence: Louise Kemp, University of Geneva, Department of Microbiology and Molecular Medicine, CMU - rue Michel-Servet 1, 1211 Geneva 4, Switzerland. Tel.: +41 (0)22 379 5656; Fax: +41 22 379 5702; e-mail: louise.kemp@unige.ch

Abstract

Rhoptries are club-shaped secretory organelles located at the anterior pole of species belonging to the phylum of Apicomplexa. Parasites of this phylum are responsible for a huge burden of disease in humans and animals and a loss of economic productivity. Members of this elite group of obligate intracellular parasites include Plasmodium spp. that cause malaria and Cryptosporidium spp. that cause diarrhoeal disease. Although rhoptries are almost ubiquitous throughout the phylum, the relevance and role of the proteins contained within the rhoptries varies. Rhoptry contents separate into two intra-organellar compartments, the neck and the bulb. A number of rhoptry neck proteins are conserved between species and are involved in functions such as host cell invasion. The bulb proteins are less well-conserved and probably evolved for a particular lifestyle. In the majority of species studied to date, rhoptry content is involved in formation and maintenance of the parasitophorous vacuole; however some species live free within the host cytoplasm. In this review, we will summarise the knowledge available regarding rhoptry proteins. Specifically, we will discuss the role of the rhoptry kinases that are used by Toxoplasma gondii and other coccidian parasites to subvert the host cellular functions and prevent parasite death.

Ancillary