Acquisition of Host Cytosolic Protein by Toxoplasma gondii Bradyzoites

• DOI: 10.1128/msphere.00934-20
• Publication Date: 2021-01-27T13:28:19Z
• Authors: Geetha Kannan; Pariyamon Thaprawat; Tracey L. Schultz; Vern B. Carruthers
• Keywords: Intracellular parasite

Toxoplasma gondii is a protozoan parasite that persists in the central nervous system as intracellular chronic-stage bradyzoites are encapsulated by thick cyst wall. While wall separates from host cytosol, it has been posited small solutes can traverse to sustain bradyzoites. Recently, was found cytosolic macromolecules cross parasitophorous vacuole and ingested digested actively replicating acute-stage tachyzoites. However, extent which have an active ingestion pathway remained unknown. To interrogate this, we modified previously published protocols look at tachyzoite acquisition digestion of proteins measuring accumulation host-expressed reporter protein after impairment endolysosomal protease (cathepsin L [CPL]). Using two cystogenic strains (ME49 Pru), demonstrate T. ingest host-derived mCherry. Bradyzoites acquire mCherry within 4 h invasion formation. This study provides direct evidence be internalized across infected cells.IMPORTANCE Chronic infection humans with common, but little known about how this obtains resources needs persist indefinitely inside neurons muscle cells. Here, provide form internalize cytosol cells despite residing surrounded We also show parasites enhanced disruption protease, suggesting such normally degraded generate peptides amino acids. Taken together, our findings imply digest proteins, potentially support its persistence.