Karenia brevis is a toxic marine dinoflagellate that causes harmful algal blooms (HABs), also known as red tides, in the Gulf of Mexico. These blooms are responsible for massive fish kills, shellfish bed contaminations, adverse human health effects, and vast economic loss. For these reasons, extensive research has gone into understanding the mechanisms and dynamics of bloom behavior by studying K. brevis in the field and in the lab. In order to understand higher order bloom behavior and dynamics it is imperative to understand K. brevis at the cellular level. In growing K. brevis in vitro under a variety of conditions, we have noted a distinct shift in the size of both ribosomal RNAs upon culturing cells under “stress” conditions, namely nutritional stress, cold shock, and decreased salinity. When the total RNA is extracted we have detected aberrant rRNA bands on the microcapillary electrophoresis BioAnalyzer (Agilent, Inc.) Interestingly when stressed, the large ribosomal subunit (LSU) becomes larger in size, and the small ribosomal subunit (SSU) becomes smaller. The initial hypothesis was that these aberrant bands were from some intracellular organism which was escaping a dying host. Through microscopy we were not able to support this hypothesis. Subsequently we also considered this response to be something K. brevis does in response to stress. This response by K. brevis had not been previously described in the literature. RNAs, pre- and post-stress, are being fully sequenced to determine how they are different, and what mechanisms may be responsible for producing them: alternative splicing, different transcriptional initiation or termination sites, or different loci? These results will help us understand the molecular events surrounding K. brevis survival under certain environmental conditions, which may have implications regarding K. brevis biogeographical distribution and bloom termination.
","abstract_html":"<p><em>Karenia brevis</em> is a toxic marine dinoflagellate that causes harmful algal blooms (HABs), also known as red tides, in the Gulf of Mexico. These blooms are responsible for massive fish kills, shellfish bed contaminations, adverse human health effects, and vast economic loss. For these reasons, extensive research has gone into understanding the mechanisms and dynamics of bloom behavior by studying <em>K. brevis</em> in the field and in the lab. In order to understand higher order bloom behavior and dynamics it is imperative to understand <em>K. brevis</em> at the cellular level. In growing <em>K. brevis</em> in vitro under a variety of conditions, we have noted a distinct shift in the size of both ribosomal RNAs upon culturing cells under “stress” conditions, namely nutritional stress, cold shock, and decreased salinity. When the total RNA is extracted we have detected aberrant rRNA bands on the microcapillary electrophoresis BioAnalyzer (Agilent, Inc.) Interestingly when stressed, the large ribosomal subunit (LSU) becomes larger in size, and the small ribosomal subunit (SSU) becomes smaller. The initial hypothesis was that these aberrant bands were from some intracellular organism which was escaping a dying host. Through microscopy we were not able to support this hypothesis. Subsequently we also considered this response to be something <em>K. brevis </em>does in response to stress. This response by <em>K. brevis</em> had not been previously described in the literature. RNAs, pre- and post-stress, are being fully sequenced to determine how they are different, and what mechanisms may be responsible for producing them: alternative splicing, different transcriptional initiation or termination sites, or different loci? These results will help us understand the molecular events surrounding <em>K. brevis </em>survival under certain environmental conditions, which may have implications regarding <em>K. brevis</em> biogeographical distribution and bloom termination.</p>","abstract_has_math":false,"creators":["Jayroe, David Scott"],"institution":null,"degree_name":"Master of Science (MS)","degree_level":"Masters Thesis","degree_discipline":"Biological Sciences","degree_department":null,"school":null,"contributors":["Shahid Karim","Tim McLean","Glen Shearer"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2015,"date_issued":"2015-05-01T07:00:00Z","date_published":"2015-05-01T07:00:00Z","updated_at":"2026-07-24T05:44:34Z","subjects":["Karenia brevis","stress","rRNA changes","HAB","Bioinformatics","Integrative Biology","Marine Biology","Microbiology"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://aquila.usm.edu/masters_theses/104","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Shahid Karim","Tim McLean","Glen Shearer"]},{"key":"dc:creator","label":"Author","values":["Jayroe, David Scott"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.available","label":"Dc Date Available","values":["2016-04-24T07:00:00Z"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Biological Sciences"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Masters Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science (MS)"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Karenia brevis","stress","rRNA changes","HAB","Bioinformatics","Integrative Biology","Marine Biology","Microbiology"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://aquila.usm.edu/masters_theses/104"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Karenia brevis is a toxic marine dinoflagellate that causes harmful algal blooms (HABs), also known as red tides, in the Gulf of Mexico. These blooms are responsible for massive fish kills, shellfish bed contaminations, adverse human health effects, and vast economic loss. For these reasons, extensive research has gone into understanding the mechanisms and dynamics of bloom behavior by studying K. brevis in the field and in the lab. In order to understand higher order bloom behavior and dynamics it is imperative to understand K. brevis at the cellular level. In growing K. brevis in vitro under a variety of conditions, we have noted a distinct shift in the size of both ribosomal RNAs upon culturing cells under “stress” conditions, namely nutritional stress, cold shock, and decreased salinity. When the total RNA is extracted we have detected aberrant rRNA bands on the microcapillary electrophoresis BioAnalyzer (Agilent, Inc.) Interestingly when stressed, the large ribosomal subunit (LSU) becomes larger in size, and the small ribosomal subunit (SSU) becomes smaller. The initial hypothesis was that these aberrant bands were from some intracellular organism which was escaping a dying host. Through microscopy we were not able to support this hypothesis. Subsequently we also considered this response to be something K. brevis does in response to stress. This response by K. brevis had not been previously described in the literature. RNAs, pre- and post-stress, are being fully sequenced to determine how they are different, and what mechanisms may be responsible for producing them: alternative splicing, different transcriptional initiation or termination sites, or different loci? These results will help us understand the molecular events surrounding K. brevis survival under certain environmental conditions, which may have implications regarding K. brevis biogeographical distribution and bloom termination.
"]},{"key":"dc:title","label":"Title","values":["Stressed Induced Changes in Karenia brevis Ribosomal RNA"]}]}],"canonical_facts":{"dc:contributor":["Shahid Karim","Tim McLean","Glen Shearer"],"dc:creator":["Jayroe, David Scott"],"dc:date.available":["2016-04-24T07:00:00Z"],"dc:description.abstract":["Karenia brevis is a toxic marine dinoflagellate that causes harmful algal blooms (HABs), also known as red tides, in the Gulf of Mexico. These blooms are responsible for massive fish kills, shellfish bed contaminations, adverse human health effects, and vast economic loss. For these reasons, extensive research has gone into understanding the mechanisms and dynamics of bloom behavior by studying K. brevis in the field and in the lab. In order to understand higher order bloom behavior and dynamics it is imperative to understand K. brevis at the cellular level. In growing K. brevis in vitro under a variety of conditions, we have noted a distinct shift in the size of both ribosomal RNAs upon culturing cells under “stress” conditions, namely nutritional stress, cold shock, and decreased salinity. When the total RNA is extracted we have detected aberrant rRNA bands on the microcapillary electrophoresis BioAnalyzer (Agilent, Inc.) Interestingly when stressed, the large ribosomal subunit (LSU) becomes larger in size, and the small ribosomal subunit (SSU) becomes smaller. The initial hypothesis was that these aberrant bands were from some intracellular organism which was escaping a dying host. Through microscopy we were not able to support this hypothesis. Subsequently we also considered this response to be something K. brevis does in response to stress. This response by K. brevis had not been previously described in the literature. RNAs, pre- and post-stress, are being fully sequenced to determine how they are different, and what mechanisms may be responsible for producing them: alternative splicing, different transcriptional initiation or termination sites, or different loci? These results will help us understand the molecular events surrounding K. brevis survival under certain environmental conditions, which may have implications regarding K. brevis biogeographical distribution and bloom termination.
"],"dc:identifier":["https://aquila.usm.edu/masters_theses/104"],"dc:subject":["Karenia brevis","stress","rRNA changes","HAB","Bioinformatics","Integrative Biology","Marine Biology","Microbiology"],"dc:title":["Stressed Induced Changes in Karenia brevis Ribosomal RNA"],"thesis:degree_discipline":["Biological Sciences"],"thesis:degree_level":["Masters Thesis"],"thesis:degree_name":["Master of Science (MS)"]},"updated_at":"2026-07-24T05:44:34Z"}