Meeting Abstract
Microplastics are degraded or manufactured plastic particles <5 mm in diameter. Microplastics pollution has become commonly and publicly recognized as a ubiquitous issue of environmental concern in water systems. Zooplankton of biological and commercial importance, including the easily cultured mysid shrimp, Americamysis bahia, have been documented to be primary consumers of microplastics. Toxins and plastics aggregate in these primary consumers, which leads to bioaccumulation in consumers further up the trophic ladder. In the presence of certain environmental stressors gene expression may be altered without changing the sequence of the DNA. One way this occurs is through methylation of the DNA, in which a methyl group can bind to the nucleotide base pairs, commonly a cytosine-guanine sequence. In different situations, DNA methylation has shown to be both short-term and reversible or permanent and potentially heritable. Microplastics exposure is a potential and increasingly common source of environmental stress. Using a Polymerase Chain Reaction (PCR) based technique known as Methylation Specific-Amplified Fragment Length Polymorphism (MS-AFLP) mysid shrimp DNA can be assessed for patterns of methylation that are potentially associated with microplastics exposure. Individuals were dosed with 5 micrometer fluorescent microplastics and compared for differential methylation expression. The experimental groups are compared to a control group sampled before any experiments occured, and to groups that were not dosed, but treated equally in procedure. As part of the experiment, microplastics were delivered with a gradual increase in concentration to determine if methylation is occurring at different rates with different lengths of exposure and different concentrations.
