Eukaryot Cell. 2010 Apr 30. [Epub ahead of print]
Host Cell Invasion by Toxoplasma gondii is Temporally Regulated by the Host Microtubule Cytoskeleton
Sweeney KR, Morrissette NS, Lachapelle S, Blader IJ.
Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104; Department of Molecular Biology and Biochemistry, University of California, Irvine, California 92697.
Toxoplasma gondii is an obligate intracellular protozoan parasite that invades and replicates within most nucleated cells of warm-blooded animals. The basis for this wide host cell tropism is unknown but could be because parasites invade host cells using distinct pathways and/or repertoires of host factors. Using synchronized parasite invasion assays, we find that host microtubule disruption significantly reduces parasite invasion into host cells early after stimulating parasite invasion but not at later time points. Host microtubules are specifically associated with the moving junction, which is the site of contact between the host cell and the invading parasite. Host microtubules are specifically associated with the moving junction of those parasites invading early after stimulating invasion but not with those invading later. Disruption of host microtubules has no effect on parasite contact, attachment, motility, or rate of penetration. Rather host microtubules hasten the time before parasites commence invasion. This effect on parasite invasion is distinct from the role that host microtubules play in bacterial and viral infections where they function to traffic the pathogen or pathogen-derived material from the host cell's periphery to its interior. These data indicate that the host microtubule cytoskeleton is a structure used by Toxoplasma to rapidly infect its host cell and highlight a novel function for host microtubules in microbial pathogenesis.
PMID: 20435700 [PubMed - as supplied by publisher]