De novo assembly of a zoanthid transcriptome for the study of corallicolids

The discovery of widespread apicomplexan symbionts of anthozoans, known as corallicolids, has raised many questions about their evolutionary history, physiology, and ecology. However, gathering molecular data from these unicellular eukaryotes is challenging due to their small size, low abundance in host tissue, and inconsistent prevalence in host populations. This task is further complicated by the presence of contamination from host genetic material in the samples. Parazoanthus swiftii is a corallicolid host with a high infection rate and no dinoflagellate symbionts making it a potentially useful model for this association. The objective of my thesis is to develop baseline genetic resources for the study of P. swiftii and its symbionts using transcriptomics. Several P. swiftii transcriptomes were sequenced, assembled, and filtered, and BUSCO analysis detected 88% of proteins from a set of conserved orthologs. Although less than half of the transcripts were functionally annotated, 56% of predicted proteins were present across all of the samples. Two of the five samples had a diverging expression profile and lower relative expression of anthozoan transcripts. The dataset also contained 1059 potential apicomplexan genes, including three that were lineage-specific. This transcriptome will aide in the study of corallicolids and their host associations, as well as add to the number of genetic resources available for zoanthids.Science, Faculty ofBotany, Department ofGraduat