Document Type

Honors Project

Publication Date



Biomphalaria glabrata, a freshwater snail belonging to the phylum Mollusca and the class gastropoda, is an intermediate host to the parasite Schistosoma mansoni, one of the species causing the disease schistosomiasis in humans. Research on B. glabrata has mainly focused on the host-parasite interaction and the immune response to S. mansoni, with very little research done on the development of the nervous system in B. glabrata-the embryonic and the ganglionic nervous systems. This project aims to examine the development of the central nervous system in B. glabrata from an embryonic nervous system, consisting of a network of neurons, to a ganglionic nervous system, consisting of clusters of neuronal cell bodies known as ganglia – gangliogenesis. Immunofluorescence is used to study the localization and the morphology of the central nervous system in the snail, allowing the determination of the onset of gangliogenesis. Additionally, through the analysis of transcriptomes (RNA sequence-data) we were able to investigate genes potentially involved in the development of the nervous system and hypothesize which genes may play a role in regulating gangliogenesis in B. glabrata. Hence, the cumulative data acquired using immunofluorescence and RNA sequencing we were able to determine the onset of gangliogenesis around 5-6 days post hatching juveniles, demonstrate for the first time that synapsin can be used as a neural marker in B.glabrata, the genes that potentially play a role in gangliogenesis, and that a ganglionic central nervous system is apparent around 27-28 days post hatching juveniles.

Level of Honors

magna cum laude




Judith Humphries