Project description:Epigenetic variation has the potential to control environmentally dependent development and contribute to phenotypic responses to local environments. Environmental epigenetic studies of sexual organisms confirm the responsiveness of epigenetic variation, which should be even more important when genetic variation is lacking. A previous study of an asexual snail, Potamopyrgus antipodarum, demonstrated that different populations derived from a single clonal lineage differed in both shell phenotype and methylation signature when comparing lake versus river populations. Here, we examine methylation variation among lakes that differ in environmental disturbance and pollution histories. The differential DNA methylation regions (DMRs) identified among the different lake comparisons suggested a higher number of DMRs and variation between rural Lake 1 and one urban Lake 2 and between the two urban Lakes 2 and 3, but limited variation between the rural Lake 1 and urban Lake 3. DMR genomic characteristics and gene associations were investigated. Observations suggest there is no effect of geographic distance or any consistent pattern of DMRs between urban and rural lakes. Environmental factors may influence epigenetic response.
Project description:Gymnocypris przewalskii przewalskii is distributed in Qinghai Lake, the largest inland saltwater lake in China. It is the only Cyprinidae fish in the Qinghai Lake water system and has extremely strong adaptability to the ecological environment with high salinity. G. p. przewalskii originates from the freshwater species Gymnocypris eckloni eckloni in the Yellow River and has a freshwater subspecies, Gymnocypris przewalskii ganzihonensis, distributed in the Ganzi River. Therefore, G. p. przewalskii is considered an ideal material for studying the high salt adaptation of plateau fish. Previous studies have characterized the evolutionary basis of highland adaptation in G. p. przewalskii; however, its adaptability to highly saline aquatic environments remains elusive. In the current study, we performed physiological, histological, genomic and transcriptomic analyses to investigate the phenotypical adaptation of G. p. przewalskii to a high saline environment and the underlying genomic and regulatory bases.
Project description:Transcripts of the gill epithelium from three different stocks of Atlantic salmon (Salmo salar) migrating from freshwater river to lake (Saimaa stock, SS), brackish water (Neva stock, NS) or seawater (Teno stock, TS) were compared at three successive developmental stages (parr, smolt and postsmolt) using the 16K GRASP cDNA microarray platform.
Project description:We examined adaptive morphological divergence and epigenetic variation in genetically impoverished asexual populations of a freshwater snail, Potamopyrgus antipodarum from distinct environments. These populations exhibit environment-specific adaptive divergence in shell shape and significant genome wide DNA methylation differences among differentially adapted lake and fast water flow river populations. The epigenetic variation correlated with adaptive phenotypic variation in rapidly adapting asexual animal populations. This provides one of the first examples of environmentally-driven differences in epigenetics that associates with adaptive phenotypic divergence.
Project description:We examined adaptive morphological divergence and epigenetic variation in genetically impoverished asexual populations of a freshwater snail, Potamopyrgus antipodarum from distinct environments. These populations exhibit environment-specific adaptive divergence in shell shape and significant genome wide DNA methylation differences among differentially adapted lake and fast water flow river populations. The epigenetic variation correlated with adaptive phenotypic variation in rapidly adapting asexual animal populations. This provides one of the first examples of environmentally-driven differences in epigenetics that associates with adaptive phenotypic divergence.
