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Updated: Jun 28, 2026
07:02
Extracellular Multi-Unit Recording from the Olfactory Nerve of Teleosts
Published on: October 6, 2020
Hormones and receptors in fish: do duplicates matter?
Graeme J Roch1, Sheng Wu, Nancy M Sherwood
1Department of Biology, University of Victoria, Victoria, BC, Canada V8W 3N5.
General and Comparative Endocrinology
|November 15, 2008
Summary
Modern fish possess duplicate genes from ancient whole-genome duplications, particularly within the secretin hormone superfamily. These duplicates offer new research avenues in fish endocrine systems.
Area of Science:
- Evolutionary Biology
- Comparative Genomics
- Endocrinology
Background:
- Modern fish evolved through extensive genomic changes, including three whole-genome duplications.
- Retained duplicate genes significantly influence metabolism, transcription, neurogenesis, and development.
- The secretin hormone superfamily, comprising ten hormones and receptors, plays crucial roles in physiological processes.
Purpose of the Study:
- To investigate the consequences of the teleost-specific genome duplication (350 mya) on secretin superfamily hormones and receptors in five fish species.
- To evaluate the status and evolutionary trajectory of duplicate genes within this superfamily across different fish genomes.
Main Methods:
- Literature review and extensive database searches of fish genomes (zebrafish, fugu, medaka, stickleback, rainbow trout).
- Analysis of orthologs and duplicate gene copies within the secretin superfamily.
- Examination of chromosome locations and synteny to support large-scale duplication events.
Main Results:
- All five fish species possess near-complete ortholog sets for the human secretin superfamily, except for secretin and its receptor.
- Receptor orthologs are widespread, with zebrafish retaining duplicate copies for seven hormones and five receptors.
- Novel adaptations include a modified glucagon receptor (GLP-1 receptor) and the presence of specific PHI and GHRH-like peptide receptors.
Conclusions:
- Teleost fish exhibit significant retention and diversification of secretin superfamily genes post-duplication.
- Duplicate genes in the secretin superfamily represent a largely unexplored resource for endocrine research in fish.
- Comparative genomic analysis reveals unique evolutionary pathways for hormone-receptor systems in fish.
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