Details

Autor(en) / Beteiligte

• Cao, Jun
• Kaneko, Osamu
• Thongkukiatkul, Amporn
• Tachibana, Mayumi
• Otsuki, Hitoshi
• Gao, Qi
• Tsuboi, Takafumi
• Torii, Motomi

Titel

Rhoptry neck protein RON2 forms a complex with microneme protein AMA1 in Plasmodium falciparum merozoites

Ist Teil von

• Parasitology international, 2009-03, Vol.58 (1), p.29-35

Ort / Verlag

Netherlands: Elsevier Ireland Ltd

Erscheinungsjahr

2009

Quelle

MEDLINE

Beschreibungen/Notizen

• Abstract Erythrocyte invasion is an essential step in the establishment of host infection by malaria parasites, and is a major target of intervention strategies that attempt to control the disease. Recent proteome analysis of the closely-related apicomplexan parasite, Toxoplasma gondii , revealed a panel of novel proteins (RONs) located at the neck portion of the rhoptries. Three of these proteins, RON2, RON4, and RON5 have been shown to form a complex with the microneme protein Apical Membrane Protein 1 (AMA1). This complex, termed the Moving Junction complex, localizes at the interface of the parasite and the host cell during the invasion process. Here we characterized a RON2 ortholog in Plasmodium falciparum. Pf RON2 transcription peaked at the mature schizont stage and was expressed at the neck portion of the rhoptry in the merozoite. Co-immunoprecipitation of Pf RON2, Pf RON4 and Pf AMA1 indicated that the complex formation is conserved between T. gondii and P. falciparum , suggesting that co-operative function of the rhoptry and microneme proteins is a common mechanism in apicomplexan parasites during host cell invasion. Pf RON2 possesses a region displaying homology with the rhoptry body protein Pf RhopH1/Clag, a component of the RhopH complex. However, here we present co-immunoprecipitation studies which suggest that Pf RON2 is not a component of the RhopH complex and has an independent role. Nucleotide polymorphism analysis suggested that Pf RON2 was under diversifying selective pressure. This evidence suggests that RON2 appears to have a fundamental role in host cell invasion by apicomplexan parasites, and is a potential target for malaria intervention strategies.