Multi-omics responses in tree swallow (Tachycineta bicolor) nestlings from the Maumee Area of Concern, Maumee River, Ohio. Tachycineta bicolor isolate:S2

Tree swallows (Tachycineta bicolor) have been used extensively over the past 20 years as a model to evaluate the movement of sediment contaminants to birds, partially because of the ease of setting up nest boxes and attracting occupants, but also because of their feeding strategies, so they are indicative of local contamination. A well assembled tree swallow genome is needed for RNA-Seq analysis and transcriptomic responses were highly correlated with the site condition, land-use, and contamination profiles. Liver tissue was utilized for transcriptome and metabolome evaluation. A significantly differentially expressed gene cluster related to a downregulation in cell growth and cell cycle regulation was identified when comparing all Maumee River sites with the reference site. There was an up-regulation of lipogenesis genes at two industrial land-use sites relative to other waste water treatment sites. We propose to use transcriptomic responses in tree swallow nestlings as comprehensive physiological endpoints to assess and monitor beneficial use impairment and site conditions.