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- Title
- Characterization of calpain activity in response to microplastic exposure in Donax variabilis.
- Author
- Schroeder, Hans Erik
- Abstract/Description
-
Coquina clams (Donax variabilis) are small multicolored bivalve mollusks that inhabit the intertidal zones of various southeastern beaches along the eastern coast of the United States where they are in great abundance and an essential part of the beach ecosystem. Because they are filter-feeders that are exposed to environmental hazards, Donax variabilis populations are a sign of the beach's ecological health. Potentially, this mollusk may be effective as a "canary in a coal mine" if...
Show moreCoquina clams (Donax variabilis) are small multicolored bivalve mollusks that inhabit the intertidal zones of various southeastern beaches along the eastern coast of the United States where they are in great abundance and an essential part of the beach ecosystem. Because they are filter-feeders that are exposed to environmental hazards, Donax variabilis populations are a sign of the beach's ecological health. Potentially, this mollusk may be effective as a "canary in a coal mine" if biological changes are easily measurable that may be sensitive to important environmental changes. One such mechanism are the calpains. Calpains are Ca2+-dependent cysteine proteases that are expressed in nearly all eukaryotes, but have rarely been studied in invertebrates like the Coquina clam. It is well established that calpains are essential to cellular homeostasis and have been implicated in a multitude of cellular functions, such as apoptosis and cellular stress. In recent years, microplastics, plastic particles that range in size but are less than 5mm, have become a serious hazard to the environment. Accumulation of microplastics have only recently been recognized to be harmful to marine organisms that ingest them and cause tissue damage on a cellular and subcellular level that may alter calpain activity. Although Coquina clams are in great abundance on the beaches and their ecological patterns have been studied thoroughly, the cellular and subcellular processes of the Coquina clam have not been studied extensively. Specifically, it is not understood how calpains function under normal conditions or how these molecules would be affected due to large ecological impacts in the form of contaminants like microplastics. It is our contention that Coquina clams can be used as a bioindicator of healthy beaches and aid in assessing the presence or absence of pollutants such as microplastics that can occur in the ecosystem, using cellular and subcellular processing by calpains as a measure.
Show less - Date Issued
- 2019, 2019
- Identifier
- 1153167661, WFE0000699
- Format
- Document (PDF)
- Title
- Microplastics in sandy environments in the Florida Keys and the Panhandle of Florida and ingestion by sea cucumbers and sand dollars.
- Author
- Plee, Tara Ashley
- Abstract/Description
-
Microplastic pollution is an increasing problem in the marine environment. This study had five research objectives: establish if seagrass habitats are accumulating more microplastics compared to sandy habits in the Florida Keys; determine if there are microplastics present in sea cucumbers in the Florida Keys; determine the number of microplastics in Pensacola Beach sediment; determine the number of microplastics in St. Joseph Bay sediment; determine if there are microplastics present in sand...
Show moreMicroplastic pollution is an increasing problem in the marine environment. This study had five research objectives: establish if seagrass habitats are accumulating more microplastics compared to sandy habits in the Florida Keys; determine if there are microplastics present in sea cucumbers in the Florida Keys; determine the number of microplastics in Pensacola Beach sediment; determine the number of microplastics in St. Joseph Bay sediment; determine if there are microplastics present in sand dollars in the panhandle of Florida; and conduct a laboratory experiment on the sand dollar Mellita tenuis to determine if it is selecting for microplastics. Microplastics were extracted from samples using a saturated CaCl2 solution and visual examination. Both seagrass beds and sandy areas in the Florida Keys contained microplastics. Sediment near Pensacola Beach and in St. Joseph Bay contained microplastics. Sea cucumbers collected in the Florida Keys and sand dollars collected in the panhandle of Florida had microplastics as part of their gut content. In the laboratory, M. tenuis ingested microbeads in slightly lower proportions compared to surrounding sediment. Both sea cucumbers and sand dollars may make useful animals for monitoring sandy environments for microplastics pollution.
Show less - Identifier
- 1129598452, WFE0000667
- Format
- Document (PDF)