Meeting Abstract

P1.87  Saturday, Jan. 4 15:30  Employing a DNA methylation-sensitive assay to elucidate the effects of ocean acidification on larvae of the Pacific Oyster (Crassostrea gigas). JOHNSON, KM*; HOFMANN, GE; Univ. of California, Santa Barbara; Univ. of California, Santa Barbara kevin.johnson@lifesci.ucsb.edu

Environmental stress can promote epigenetic modifications (e.g. changes in DNA methylation) that regulate gene expression. This interaction between DNA methylation and gene expression produces many of the phenotypic changes that are collectively referred to as an organism’s phenotypic plasticity. We utilized the Methylation-Sensitive Amplification Polymorphism (MSAP) assay to investigate the effects of ocean acidification (OA) on five target genes after exposure to future ocean conditions during the early developmental stages of the Pacific Oyster (Crassostrea gigas). The five target genes (Annexin, Calcitonin receptor, Calmodulin, Fascilin, and Troponin C) were selected based on a previous proteomic study that identified these proteins as significantly differentially expressed under OA conditions. Oyster larvae were raised at 25°C with two pCO₂ levels (300 and 1200 µatm) for 6 days. Samples were taken daily to monitor growth and development between the two treatments. For qPCR and MSAP analysis, samples were taken from the gametes prior to fertilization and on developmental days 1, 2, 3, and 6. The physical data highlight that while larval sizes were significantly affected in the elevated pCO₂ treatment there was no detectable effect on their developmental rate. The data from the qPCR and MSAP procedures will also be presented as assays are currently underway.