Mol Biol Cell. 2013 Apr 24. [Epub ahead of print]
Toxoplasma gondii salvages sphingolipids from the host Golgi through the rerouting of selected Rab vesicles to the parasitophorous vacuole
Romano JD, Sonda S, Bergbower E, Smith ME, Coppens I
Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205, USA Institute of Parasitology, University of Zurich, CH-8057, Switzerland
The obligate intracellular protozoan Toxoplasma gondii actively invades mammalian cells and, upon entry, forms its own membrane-bound compartment, named the parasitophorous vacuole (PV). Within the PV, the parasite replicates and scavenges nutrients, including lipids, from host organelles. Although T. gondii can synthesize sphingolipids de novo, it also scavenges these lipids from the host Golgi. How the parasite obtains sphingolipids from the Golgi remains unclear as the PV avoids fusion with host organelles. In this study, we have explored the host Golgi-PV interaction and evaluated the importance of host-derived sphingolipids for parasite growth. We demonstrate that the PV preferentially localizes near the host Golgi early during an infection and remains closely associated with this organelle throughout infection. The parasite subverts the structure of the host Golgi, resulting in its fragmentation into numerous mini-stacks, which surround the PV, and hijacks host Golgi-derived vesicles within the PV. These vesicles, marked with Rab14, Rab30 or Rab43, colocalize with host-derived sphingolipids in the vacuolar space. Scavenged sphingolipids contribute to parasite replication since alterations in host sphingolipid metabolism are detrimental for the parasite's growth. Thus, our results reveal that T. gondii relies on host-derived sphingolipids for its development and scavenges these lipids via Golgi-derived vesicles.
PMID: 23615442 [PubMed - as supplied by publisher]