Conservation Genetics and Genomics of the Acipenseridae: Tools for Delineating Fundamental Units of Management, Evolutionary Significant Lineages, and Evolutionary Adaptive Potential

An integrative, systems biology approach that identifies and sustains ecological processes and evolutionary lineages is needed to manage and conserve the biodiversity present in members of the Acipenseridae.  Inherent in such an approach is the identification and characterization of associated migration, colonization, and extinction processes among populations.  The geographic ranges of most species are much larger than the typical dispersal distances of individuals (or gametes).  This creates an opportunity for the generation and maintenance of extensive genetic differences among geographic populations in spite of migration.  The degree to which local populations are physically separated from one another partly determines rates of gene flow and/or recolonization among populations.  Range-wide surveys of nDNA variation have been conducted for two Atlantic coast species: Atlantic sturgeon Acipenser oxyrinchus and shortnose sturgeon A. brevirostrum.  The management relative results of these surveys will be presented.Because natural selection ultimately acts on the genetic variation underlying character variation, identifying the genes associated with parallel evolutionary changes among recently diverged lineages is essential to uncovering candidate genes implicated in adaptive phenotypic variance.  Contemporary genomic approaches can be particularly useful for identifying genetic targets of selection and genetic mechanisms of adaptation even among recently diverged lineages.  I will present the results of research directed at: 1) transcriptome assembly for both A. oxyrinchus and A. brevirostrum; 2) identifying genes for use in taxonomic resolution among all Acipenseridae; and 3) performing comparative gene expression profiles to provide insights into whether the genetic differentiation observed among Atlantic coast drainages are adaptive.  This research is allowing identification of metabolically critical genes, as well as, genes that can assist in elucidating taxonomically-, phylogeographically-, and demographically-informative processes.