Meeting Abstract

P1.49  Friday, Jan. 4  Genetic and Epigenetic Population Structure in Spartina alterniflora FOUST, C.M.*; SCHREY, A.W.; RICHARDS, C.L.; Univ. of South Florida; Armstrong Atlantic State Univ.; Univ. of South Florida christyfoust@mail.usf.edu

Phenotypic plasticity of ecologically relevant traits is important to an organism’s response to environmental variation within populations; however, the underlying mechanisms of plasticity are largely unknown. Ecological epigenetics, the study of changes in gene expression not due to changes in DNA sequence, may explain one of the mechanisms underlying phenotypic plasticity. Variation in DNA methylation can cause phenotypic variation among individuals, allow for an individual’s response to changing environments, and can be stably transmitted across generations. The current study examines genetic and epigenetic variation and population structure in Spartina alterniflora along environmental gradients among multiple sites on Sapelo Island, Georgia in May 2011. We collected leaf samples along 10m transects (n=20 for each microhabitat) in low, middle, and high marsh areas, respectively, within each site. Each microhabitat corresponds to plants with different phenotypes for height (tall, intermediate, short, respectively). We screened AFLP and methylation sensitive AFLP (MS-AFLP) markers for genetic and epigenetic variation, respectively. If S. alterniflora responds to the different microhabitats via phenotypic plasticity, we expect to detect no genetic differentiation among microhabitats. If variation in DNA methylation corresponds to phenotypic variation but cannot be explained by genetic variation, our results would suggest that epigenetic regulation of certain genomic elements may be important in dealing with variable environmental conditions. Future studies addressing DNA methylation and gene expression will help to determine if epigenetics contributes to phenotypic plasticity and habitat differentiation of different phenotypes.