Date Available


Year of Publication


Degree Name

Master of Science (MS)

Document Type

Master's Thesis


Agriculture, Food and Environment


Veterinary Science

First Advisor

Dr. Daniel K. Howe


Sarcocystis neurona is a protozoan parasite that causes a rare neurological disorder in horses called Equine Protozoal Myeloencephalitis (EPM). Apicomplexa use actin-myosin based motor and organelle secretion to interact with the host cell and invade it. Despite the importance of motility and invasion-needed factors, the mechanisms by which S. neurona employs host cell association strategies to interact remains largely undefined. To address this knowledge gap, we hypothesize that just like other Apicomplexa, S. neurona utilizes actin polymerization for substrate-dependent gliding. Moreover, we also hypothesize that micronemes of S. neurona secrete proteins that are calcium-dependent. Based on previous studies in T. gondii, freshly harvested S. neurona merozoites are treated with actin-polymerization inhibitor (Cytochalasin-D) or intracellular-calcium inducers (Ethanol, ionophore A23187) or intracellular-calcium chelator (BAPTA-AM) or bumped-kinase inhibitor (BKI-1553). Data obtained from each experiment is analyzed to assess whether there is any variation in motility/secretion upon treatment with previously mentioned drugs. Results suggest that S. neurona employs actin-myosin motor and likely calcium-based microneme secretion for motility; implicating the role of host-parasite interactions in EPM since motility/secretion is required for causing infection.

Digital Object Identifier (DOI)