Date of Award
8-2025
Degree Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
School
Biological, Environmental, and Earth Sciences
Committee Chair
Nicole Phillips
Committee Chair School
Biological, Environmental, and Earth Sciences
Committee Member 2
Alex Flynt
Committee Member 2 School
Biological, Environmental, and Earth Sciences
Committee Member 3
Jake Schaefer
Committee Member 3 School
Biological, Environmental, and Earth Sciences
Committee Member 4
Dmitri Mavrodi
Committee Member 4 School
Biological, Environmental, and Earth Sciences
Committee Member 5
Hao Xu
Committee Member 5 School
Biological, Environmental, and Earth Sciences
Abstract
RNA biology is a rapidly expanding field, with many avenues of discovery among marine organisms. In this study, we analyze both mollusks and sawfish. First, we perform an evaluation of sRNA biogenesis pathways throughout Mollusca, with emphasis on the easter oyster, Crassostrea virginica. Understanding these molecules prescribes RNAi-based gene silencing approaches, benefiting genetic investigation and biotechnology. Similar to other animal groups, mollusks have conserved microRNAs (miRNAs), with some shared with ecdysozoans and deuterostomes; however, there is no evidence of an endogenous small interfering RNA (siRNA) pathway. These results suggest that long double-stranded RNA (dsRNA)-based RNAi is not appropriate for gene silencing in mollusks as well as other members of the broader Lophotrochozoan clade. The study also finds an abundance of piwi-interacting RNAs (piRNAs) in both soma and gonads. Differences are also found in piRNA biology. Many invertebrates exhibit somatic piRNAs; however, mollusk piRNAs appear to be restricted to a subset of cells, limiting the potential of piRNA-based RNAi. Further, individual animals also express a unique collection of piRNAs that seem to be only partially determined through inheritance from both parents. Furthermore, we also investigated the RNA biology of ovotestes prevalent in male smalltooth sawfish, Pristis pectinata. We find that the ovotestis has significantly different gene expression from either normal ovary or testis tissue, with immunity, hormones, and sex determination potentially affected by this abnormal tissue. Collectively, our research provides insight into Mollusca’s sRNA biogenesis pathways and Elasmobranchii’s ovotestis formation, broadening our understanding of gene regulation in various marine genomes.
Copyright
Cory Von Eiff, 2025
Recommended Citation
Von Eiff, Cory, "Applying Transcriptomics for Technology Development and Conservation in North American Marine Organisms" (2025). Dissertations. 2384.
https://aquila.usm.edu/dissertations/2384
Microsoft Word Version
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