Rock snot in the age of transcriptomes : using a phylogenetic framework to identify genes involved in diatom extracellular polymeric substance-secretion pathways

dc.contributor.advisorTheriot, Edward C. (Edward Claiborne), 1953-
dc.contributor.advisorJansen, Robert K., 1954-
dc.creatorAshworth, Matt Peteren
dc.date.accessioned2014-11-21T15:18:35Zen
dc.date.accessioned2018-01-22T22:27:10Z
dc.date.available2018-01-22T22:27:10Z
dc.date.issued2013-12en
dc.date.submittedDecember 2013en
dc.date.updated2014-11-21T15:18:35Zen
dc.descriptiontexten
dc.description.abstractWe are coming to understand that the ecological importance of diatoms is not limited to primary productivity, as many diatoms produce extracellular polymeric substances (EPS), which are vital components in algal and bacterial “biofilms.” While great effort has been made to chemically identify the types of molecules and polymers used to create and modify diatom EPS there is still much about the process we do not know. Rather than studying this process chemically, we have elected to search for the genes involved in EPS production and secretion. We assembled transcriptomes from three EPS-producing diatoms (Cyclophora tenuis, Lucanicum concatenatum, Thalassionema frauenfeldii) and two diatoms which do not (Astrosyne radiata, Thalassionema sp. ‘BlueH20’). In an attempt to limit the differences to EPS-related transcripts, the taxa were selected in a phylogenetic framework (which is also discussed in this dissertation), where EPS-producing taxa were closely-related to taxa which did not produce EPS (A. radiata, C. tenuis, L. concatenatum as one set, T. frauenfeldii and T. sp. ‘BlueH20’ as the other). The resulting pool of transcripts sorted for contigs which appeared in the EPS-producing taxa but not their closely-related non EPS-producing counterparts, and those contigs were then compared to two annotated diatom genomes and sorted by function, looking specifically for genes related to secretion, polysaccharide assembly or modification and carbohydrate metabolism. In the Thalassionema clade, 41 contigs with the aforementioned annotations were found, while 22 such contigs were found in the Cyclophora/Lucanicum/Astrosyne clade. These putative EPS-related markers are identified in this dissertation for further study on their function and evolution across diatoms.en
dc.description.departmentPlant Biologyen
dc.format.mimetypeapplication/pdfen
dc.identifier.urihttp://hdl.handle.net/2152/27631en
dc.subjectDiatomsen
dc.subjectExtracellular polymeric substancesen
dc.subjectPhylogenyen
dc.subjectTranscriptomesen
dc.titleRock snot in the age of transcriptomes : using a phylogenetic framework to identify genes involved in diatom extracellular polymeric substance-secretion pathwaysen
dc.typeThesisen

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