EXPRESSED SEQUENCE TAGS IN RAINBOW TROUT INTESTINE, LIVER, AND KIDNEY (Oncorhynchus mykiss)

¹ Division of Animal and Veterinary Sciences, West Virginia University, 6108 Evansdale Drive, Morgantown, WV 26506-6108

² University of Illinois Department of Animal Sciences 210 Meat Science Lab, Urbana, IL 61801

³ National Center for Cool and Cold Water Aquaculture 11876 Leetown Road, Kearneysville, WV 25430

Examining number of redundant ESTs from non-normalized libraries produces relative expression profiles, as frequency of cDNAs reflects mRNA abundance. This study reports novel genes as well as relative gene expression profiles in rainbow trout. Double-stranded plasmid DNA templates prepared from rainbow trout intestine, liver, and kidney cDNA libraries were subjected to single-pass sequencing of 5' ends of each cDNA clone. Alignments of the EST sequences were performed with Gene Tools 1.0 software (Edmonton, AB, Canada). Classification of clones was based on similarity to NCBI dbEST entries; vector-derived sequence and ambiguous sequences were not included in analyses. Significant matches had probabilities less than 0.001. ESTs were classified into functional categories by similarity of annotated sequences. Relative expression was estimated from the total number of clones sequenced. Sixty-eight clones from the intestine library were from 40 genes (seven previously reported), 35 clones were from 34 potential genes. Seven were redundant. Genes with the greatest expression were 28S ribosomal protein (16.5%) and beta actin (5.8%). The liver library yielded 63 clones from 29 genes (nine previously reported), 36 clones from 34 potential genes. Eleven were redundant. Serum albumen and apolipoprotein represented 16.1% and 7.0% of total clones, respectively. The kidney library yielded 57 clones from 37 genes (seven previously reported), 45 clones from 40 potential genes. Eight were redundant. Most abundant clones were beta actin (11.6%) and ribosomal protein (9.7%).