PhD Oral Defense: Protein-Protein Interactions of Receptors LdPEX5 and LPEX7 with PTS1 and PTS2 Cargo Proteins, and with Glycosomal Docking Protein LdPEX14 for Protein import into Leishmania donovani
PhD Oral Defense of Rona Strasser, Institute of Parasitology
A unique subcellular structure found in Leishmania donovani is the glycosome. This organelle compartmentalizes the enzymatic machinery required for multiple metabolic pathways, including glycolysis. Correct targeting of glycosomal enzymes is essential for parasite viability. Proteins targeted to the glycosome have either a C-terminal PTS1 or an N-terminal PTS2 topogenic signal sequence, which is recognized by cytosolic receptors LdPEX5 or LPEX7, respectively. These cargo-loaded receptors interact with the peroxin protein LdPEX14, located on the cytosolic face of the glycosomal membrane, an event required for import of the cargo proteins into the glycosomal lumen. However, the complete glycosomal protein import pathway has not been fully elucidated. This work has been undertaken to better understand the protein-protein interactions involved in the trafficking of cargo proteins across the glycosomal membrane.