The C-Terminus of Toxoplasma RON2 Provides the Crucial Link between AMA1 and the Host-Associated Invasion Complex

PLoS Pathogens

John C. Boothroyd¹  Jessica S. Tyler¹ 

[1] Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, California, United States of America

关键词: Parasitic diseases;    Host cells;    Glutathione chromatography;    Toxoplasma;    Cell membranes;    Membrane proteins;    Plasmodium;    Immune serum;   

DOI  :  10.1371/journal.ppat.1001282

学科分类：生物科学（综合）

来源: Public Library of Science

【 摘 要 】

Host cell invasion by apicomplexan parasites requires formation of the moving junction (MJ), a ring-like apposition between the parasite and host plasma membranes that the parasite migrates through during entry. The Toxoplasma MJ is a secreted complex including TgAMA1, a transmembrane protein on the parasite surface, and a complex of rhoptry neck proteins (TgRON2/4/5/8) described as host cell-associated. How these proteins connect the parasite and host cell has not previously been described. Here we show that TgRON2 localizes to the MJ and that two short segments flanking a hydrophobic stretch near its C-terminus (D3 and D4) independently associate with the ectodomain of TgAMA1. Pre-incubation of parasites with D3 (fused to glutathione S-transferase) dramatically reduces invasion but does not prevent injection of rhoptry bulb proteins. Hence, the entire C-terminal region of TgRON2 forms the crucial bridge between TgAMA1 and the rest of the MJ complex but this association is not required for rhoptry protein injection.

【 授权许可】

CC BY