Meeting Abstract

P1.130  Monday, Jan. 4  Development and Validation of a Quantitative, Multiplex Gene Expression Assay for Components of the Endocrine Growth Axis in Salmon LUCKENBACH, J.A.*; METZGER, D.C.; DICKEY, J.T.; SWANSON, P.; BECKMAN, B.R.; Northwest Fisheries Science Center, Seattle; Northwest Fisheries Science Center, Seattle; University of Washington, Seattle; Northwest Fisheries Science Center, Seattle; Northwest Fisheries Science Center, Seattle Adam.Luckenbach@noaa.gov

Previous studies have shown that liver mRNA and/or circulating levels of the hormone, insulin-like growth factor 1 (IGF1), may reflect the specific growth rate of salmon. It is possible, however, that a broader and more complete indication of growth status might be achieved by assessing multiple components of the endocrine growth axis. This study compared two methods for quantification of salmon growth-related mRNAs: quantitative PCR versus a custom QuantiGene® Plex (QGP) assay. The QGP technology by Panomics Inc. permits the simultaneous quantification of multiple mRNA targets within a single tissue homogenate using sequence-specific probes and requires no RNA isolation, reverse transcription, or amplification. Using liver homogenates from coho salmon (Oncorhynchus kisutch) under fed and fasted conditions, we compared detectable changes in mRNA levels between the QGP and quantitative PCR assays for insulin-like growth factors (igf1 and igf2), IGF binding proteins (igfbp1, igfbp2a, and igfbp2b), somatolactin receptor (slr) and growth hormone receptors (ghr1 and ghr2). A significant, positive correlation was found between results from the QGP and quantitative PCR assays for all mRNA targets. Coefficients of variation for technical replicate samples measured with the QGP assay were low, ranging from 0.7-2.6%, suggesting this is a suitable method for quantification of endocrine growth-related transcripts in salmon tissues.