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Date of Award


Document Type

Restricted Thesis: Campus only access

Degree Name

Bachelor of Science


Biochemistry & Molecular Biol.

First Advisor

Dr. April Hill


Symbiosis is an important interaction present throughout nature that has been observed across time. This close association between organisms can provide mutual benefits, including important survival strategies. We investigated the mutualistic interaction between freshwater sponge Ephydatia muelleri and its intracellular symbiont: Chlorella algae. Previous RNAseq experiments showed upregulation of several genes in the cAMP-dependent signaling pathway of E. muelleri during symbiosis with Chlorella, as compared to E. muelleri in the absence of symbionts. This pathway is responsible for several important cellular functions such as metabolism and protein secretion. From this pathway, we investigated E. muelleri genes including Ras and Rap for differential expression during symbiosis. We found that Ras and Rap are both upregulated in E. muelleri at several time points after the onset of symbiosis with Chlorella. We also inhibited the protein expressed by Rock, another gene from the cAMPdependent signaling pathway, to investigate the potential effects on the onset of symbiosis. We found that this method of inhibition had no significant effect on symbiosis. These studies aim to both understand genetic components of the symbiotic relationship between these species, as well as give insight into host: symbiont interactions in a changing climate.