Genomic mechanisms of evolved physiological plasticity in killifish distributed along an environmental salinity gradient.

ABSTRACT: Adaptive variation tends to emerge clinally along environmental gradients or discretely among habitats with limited connectivity. However, in Atlantic killifish (Fundulus heteroclitus), a population genetic discontinuity appears in the absence of obvious barriers to gene flow along parallel salinity clines and coincides with a physiologically stressful salinity. We show that populations resident on either side of this discontinuity differ in their abilities to compensate for osmotic shock and illustrate the physiological and functional genomic basis of population variation in hypoosmotic tolerance. A population native to a freshwater habitat, upstream of the genetic discontinuity, exhibits tolerance to extreme hypoosmotic challenge, whereas populations native to brackish or marine habitats

SUBMITTER: Whitehead A 

PROVIDER: S-EPMC3076822 | biostudies-literature | 2011 Apr

REPOSITORIES: biostudies-literature