PUBLICATION
Subfunctionalization of Expression and Peptide Domains Following the Ancient Duplication of the Proopiomelanocortin Gene in Teleost Fishes
- Authors
- de Souza, F.S., Bumaschny, V.F., Low, M.J., and Rubinstein, M.
- ID
- ZDB-PUB-050818-5
- Date
- 2005
- Source
- Mol. Biol. Evol. 22(12): 2417-2427 (Journal)
- Registered Authors
- Keywords
- POMC, teleosts, evolution, Tetraodon, beta-endorphin, subfunctionalization
- MeSH Terms
-
- Evolution, Molecular
- Phylogeny*
- Sequence Alignment
- Molecular Sequence Data
- Pro-Opiomelanocortin/genetics*
- Zebrafish/genetics*
- Amino Acid Sequence
- Gene Duplication*
- Animals
- Fishes/genetics
- Tetraodontiformes/genetics*
- PubMed
- 16093565 Full text @ Mol. Biol. Evol.
Citation
de Souza, F.S., Bumaschny, V.F., Low, M.J., and Rubinstein, M. (2005) Subfunctionalization of Expression and Peptide Domains Following the Ancient Duplication of the Proopiomelanocortin Gene in Teleost Fishes. Mol. Biol. Evol.. 22(12):2417-2427.
Abstract
The proopiomelanocortin gene (POMC) encodes several bioactive peptides including adrenocorticotropin hormone (ACTH), alpha-, beta- and gamma-MSH and the opioid peptide beta-endorphin, which play key roles in vertebrate physiology. In the human, mouse and chicken genomes there is only one POMC gene. By searching public genome projects, we have found that Tetraodon (Tetraodon nigroviridis), Fugu (Takifugu rubripes) and zebrafish (Danio rerio) possess two POMC genes, which we called POMCalpha and POMCbeta, and we present phylogenetic and mapping evidence that these paralogue genes originated in the whole-genome duplication specific to the teleost lineage over 300 million years ago. In addition, we present evidence for two types of subfunction partitioning between the paralogues: First, in situ hybridization experiments indicate that the expression domains of the ancestral POMC gene have been subfunctionalized in Tetraodon, with POMCalpha expressed in the nucleus lateralis tuberis of the hypothalamus, as well as in the rostral pars distalis and pars intermedia of the pituitary, whereas POMCbeta is expressed in the preoptic area of the brain and weakly in the pituitary pars intermedia. Second, POMCbeta genes have a beta-endorphin segment that lacks the consensus opioid signal and seems to be under neutral evolution in tetraodontids, whereas POMCalpha genes possess well-conserved peptide regions. Thus, POMC paralogues have experienced subfunctionalization of both expression and peptide domains during teleost evolution. The study of regulatory regions of fish POMC genes might shed light on the mechanisms of enhancer partitioning between duplicate genes as well as the roles of POMC-derived peptides in fish physiology.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping