Submitted to: Plant and Animal Genome VX Conference Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 1/10/2004
Publication Date: 1/10/2004
Citation: Gahr, S.A., Palti, Y., Rexroad III, C.E. 2004. Identification and characterization of two inhibitor of differentiation (id) genes in rainbow trout (oncorhynchus mykiss). Plant and Animal Genome Abstracts. p.252.
Technical Abstract: Rainbow trout have received extensive research interest for aquaculture production and as a model species for research on human health and evolutionary genetics. Gaining understanding of the mechanisms that regulate growth and development will facilitate research in this model organism and may be useful for genetic improvement of rainbow trout for aquaculture production efficiency. The Id (Inhibitors of DNA Binding/Differentiation) proteins represent a family of dominant negative regulators of the bHLH transcription factors whose activities result in delayed cell differentiation and prolonged proliferation. In this study, cDNA clones with homology to the Id proteins were used to screen a rainbow trout BAC library and identify clones containing homologous sequences. Phylogenetic analysis of the translated amino acid sequences classifies these novel genes as trout Id 6-1 and Id 6-2. Both genes were found to be composed of two exons separated by a small intron and have similar gene structures. Each encodes a 130-aa peptide in which the coding region is separated by the intron, with most of the coding region found within exon 1. The two genes are very similar in their transcribed regions (83%) but differ in their upstream (64%) and downstream (65%) sequences. TFSEARCH analysis revealed unique transcription factor binding sites in the promoter region of each gene which may signify differences in the expression pattern of the two genes. Id6 expression is being quantified using a real time-PCR assay. Additionally, the genes are being integrated into a genetic linkage map with the use of microsatellite and SNPs.