title: Identification of biomarkers of contaminant exposure in wild largescale suckers using gene expression microarrays
design: Total RNA from the liver, brain, heart, kidney, and gonad of the seven largescale suckers (3 males and 4 females) collected in 2010 was used to construct a cDNA library. All RNA samples had a RIN >7. We pooled equal amounts of each RNA sample by tissue and then generated a total RNA pool of 1.8 µg, using an equal amount of RNA from each tissue type. We synthesized cDNA from the total RNA pool with the Mint kit (Evrogen Joint Stock Company, Moscow, Russia) and constructed a normalized cDNA library using the Trimmer kit (Evrogen) per the manufacturer’s protocols. To assess the normalization of the cDNA library, we amplified the genes encoding ß-actin (normally expressed at high levels) and transforming growth factor ß1 (TGFß1; normally expressed at low levels) for 25 cycles and visualized the amplicons on a 1.5% agarose gel.