Submitted to: Biochimica et Biophysica Acta
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/28/2005
Publication Date: 4/12/2005
Citation: Gahr, S.A., Rodriguez, M.F., Rexroad III, C.E. 2005. Identification and expression profile of the id gene family in rainbow trout (oncorhynchus mykiss). Biochimica et Biophysica Acta 1729:64-73.
Interpretive Summary: The ID family of proteins participate in the regulation of growth and development in mammalian species. As understanding the molecular mechanisms driving growth and development is important to aquaculture research, we identified and characterized the ID proteins in rainbow trout. We report their DNA sequences and the expression patterns of these genes in different tissues and time points during embryonic development.
Technical Abstract: The ID proteins are negative regulators of basic helix-loop-helix transcription factors. The role of these proteins in regulating mammalian growth and development has generated interest in them as candidate genes for affecting aquaculture production traits. We report the identification and characterization of two new rainbow trout ID genes (ID1D and ID2B) and further characterization for two previously identified genes (ID1A and ID2A). Phylogenetic analysis of the predicted ID1 proteins grouped ID1A with ID1D and ID1B with ID1C suggesting a mechanism of divergence throughout salmonid evolution. Real time PCR assays were developed for each of the six rainbow trout ID transcripts to determine tissue distributions and embryonic expression. ID1 transcripts were expressed in a variety of tissues and were observed to be similar within the two groups, ID2 transcripts were observed to be differentially expressed. ID1A and ID1D expression remained unchanged throughout embryonic development. ID1B and ID1C showed low expression during early, increased during mid, and decreased during late embryonic development. The ID2 transcripts revealed the highest expression in the unfertilized eggs and day 2 embryos and remained low through the remainder of embryonic development. The expression patterns of ID transcripts indicate a complex mechanism of activity for the ID proteins in the rainbow trout.