College
College of Arts and Sciences
Mentor Information
Dr. Elena Suvorova
Description
Toxoplasma gondii is an obligate intracellular parasite infecting 30% of the global population. During host cell invasion, new parasites are formed through a budding process that partitions nuclei and organelles into daughters through a specialized form of division is known as endodyogeny. It involves closed mitosis, a single round of DNA replication, and coordinated organelle assembly within the mother cell. In cell division, centrosomes duplicate and serve as a central point for the reorganization of cytoskeletal structures known as microtubule organizing centers (MTOC). In typical eukaryotic cell division, centrosomes duplicate and migrate to opposite poles forming bipolar mitotic spindles required for chromosome segregation. Following duplication in T. gondii, centrosomes, in contrast, coordinate daughter cell scaffolds by serving as MTOCs. Centrosome-associated fibers spatially coordinate daughter cell scaffold formation. These fibers, SFA fibers, play a critical structural role in parasite division. Previous work showed that without these fibres, nuclear replication continues but daughter bud assembly fails, uncoupling karyokinesis from cytokinesis. My project focuses on the SFA fiber, TgSFA2, and its localization and function in dividing parasites. My goal is to generate tagged TgSFA2-MYC parasites, validate correct integration and then later assess functional consequences. Preliminary IFA results show that TgSFA2 localizes as punctate structures near centrosomes. The current hypothesis is SFA2 acts as a structural bridge between duplicated centrosomes and daughter bud initiation sites, ensuring spatial coupling of mitosis and cytokinesis during endodyogeny. These findings will contribute to understanding how apicomplexan parasites coordinate cytoskeletal organization during cell division.
Localization and Function of TgSFA2 During Tachyzoite Division in Toxoplasma gondii
Toxoplasma gondii is an obligate intracellular parasite infecting 30% of the global population. During host cell invasion, new parasites are formed through a budding process that partitions nuclei and organelles into daughters through a specialized form of division is known as endodyogeny. It involves closed mitosis, a single round of DNA replication, and coordinated organelle assembly within the mother cell. In cell division, centrosomes duplicate and serve as a central point for the reorganization of cytoskeletal structures known as microtubule organizing centers (MTOC). In typical eukaryotic cell division, centrosomes duplicate and migrate to opposite poles forming bipolar mitotic spindles required for chromosome segregation. Following duplication in T. gondii, centrosomes, in contrast, coordinate daughter cell scaffolds by serving as MTOCs. Centrosome-associated fibers spatially coordinate daughter cell scaffold formation. These fibers, SFA fibers, play a critical structural role in parasite division. Previous work showed that without these fibres, nuclear replication continues but daughter bud assembly fails, uncoupling karyokinesis from cytokinesis. My project focuses on the SFA fiber, TgSFA2, and its localization and function in dividing parasites. My goal is to generate tagged TgSFA2-MYC parasites, validate correct integration and then later assess functional consequences. Preliminary IFA results show that TgSFA2 localizes as punctate structures near centrosomes. The current hypothesis is SFA2 acts as a structural bridge between duplicated centrosomes and daughter bud initiation sites, ensuring spatial coupling of mitosis and cytokinesis during endodyogeny. These findings will contribute to understanding how apicomplexan parasites coordinate cytoskeletal organization during cell division.
