Epitopes described in "Proteomic analysis of rhoptry organelles reveals many novel constituents for host-parasite interactions in Toxoplasma gondii."

Article Authors:Peter J Bradley; Chris Ward; Stephen J Cheng; David L Alexander; Susan Coller; Graham H Coombs; Joe Dan Dunn; David J Ferguson; Sanya J Sanderson; Jonathan M Wastling; John C Boothroyd
Article Title:Proteomic analysis of rhoptry organelles reveals many novel constituents for host-parasite interactions in Toxoplasma gondii.
Reference Detail
Reference ID:1119
Abstract:Rhoptries are specialized secretory organelles that are uniquely present within protozoan parasites of the phylum Apicomplexa. These obligate intracellular parasites comprise some of the most important parasites of humans and animals, including the causative agents of malaria (Plasmodium spp.) and chicken coccidiosis (Eimeria spp.). The contents of the rhoptries are released into the nascent parasitophorous vacuole during invasion into the host cell, and the resulting proteins often represent the literal interface between host and pathogen. We have developed a method for highly efficient purification of rhoptries from one of the best studied Apicomplexa, Toxoplasma gondii, and we carried out a detailed proteomic analysis using mass spectrometry that has identified 38 novel proteins. To confirm their rhoptry origin, antibodies were raised to synthetic peptides and/or recombinant protein. Eleven of 12 of these yielded antibody that showed strong rhoptry staining by immunofluorescence within the rhoptry necks and/or their bulbous base. Hemagglutinin epitope tagging confirmed one additional novel protein as from the rhoptry bulb. Previously identified rhoptry proteins from Toxoplasma and Plasmodium were unique to one or the other organism, but our elucidation of the Toxoplasma rhoptry proteome revealed homologues that are common to both. This study also identified the first Toxoplasma genes encoding rhoptry neck proteins, which we named RONs, demonstrated that toxofilin and Rab11 are rhoptry proteins, and identified novel kinases, phosphatases, and proteases that are likely to play a key role in the ability of the parasite to invade and co-opt the host cell for its own survival and growth.
Affiliations:Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, California 94305, USA.
Reference Type:Literature
PubMed ID:16002398
Journal:J Biol Chem
Journal Volume:280
Article Pages:34245-58
Journal ISSN:1083-351X
Article Chemical List:Antibodies;Protozoan Proteins
Article MeSH List:Animals; Antibodies(diagnostic use); Fluorescent Antibody Technique; Host-Parasite Interactions(physiology); Immunoassay; Mass Spectrometry; Organelles(chemistry); Proteomics; Protozoan Proteins(analysis); Survival; Toxoplasma(chemistry; pathogenicity); Vacuoles
Curation Last Updated:2014-10-03 19:37:54