PUBLICATION
Adaptive evolution of the uncoupling protein 1 gene contributed to the acquisition of novel nonshivering thermogenesis in ancestral eutherian mammals
- Authors
- Saito, S., Saito, C.T., and Shingai, R.
- ID
- ZDB-PUB-100330-45
- Date
- 2008
- Source
- Gene 408(1-2): 37-44 (Journal)
- Registered Authors
- Keywords
- Positive Darwinian selection, Novel gene function, Gene duplication, Vertebrates, Comparative genomics
- MeSH Terms
-
- Acclimatization
- Adipose Tissue, Brown/physiology
- Amino Acid Sequence
- Animals
- Evolution, Molecular*
- Humans
- Ion Channels/genetics*
- Mammals/genetics
- Mammals/physiology
- Mitochondrial Proteins/genetics*
- Molecular Sequence Data
- Phylogeny
- Selection, Genetic
- Sequence Alignment
- Thermogenesis/genetics*
- Thermogenesis/physiology
- PubMed
- 18023297 Full text @ Gene
Citation
Saito, S., Saito, C.T., and Shingai, R. (2008) Adaptive evolution of the uncoupling protein 1 gene contributed to the acquisition of novel nonshivering thermogenesis in ancestral eutherian mammals. Gene. 408(1-2):37-44.
Abstract
Homeotherms possess various physiological mechanisms to maintain their body temperature, thus allowing them to adapt to various environments. Under cold conditions, most eutherian mammals upregulate heat production in brown adipose tissue (BAT), and uncoupling protein (UCP) 1 is an essential factor in BAT thermogenesis. The evolutionary origin of UCP1 was believed to have been a specific event occurring in eutherian lineages. Recently, however, the UCP1 ortholog was found in fishes, which uncovers a more ancient origin of this gene than previously believed. Here we investigate the evolutionary process of UCP1 by comparative genomic approach. We found that UCP1 evolved rapidly by positive Darwinian selection in the common ancestor of eutherians, although this gene arose in the ancestral vertebrate, since the orthologous genes were shared among most of the vertebrate species. Adaptive evolution occurred after the divergence between eutherians and marsupials, which is consistent with the fact that BAT has been found only in eutherians. Our findings indicate that positive Darwinian selection acted on UCP1 contributed to the acquisition of an efficient mechanism for body temperature regulation in primitive eutherians. Phylogenetic reconstruction of UCP1 with two paralogs (UCP2 and UCP3) among vertebrate species revealed that the gene duplication events which produced these three genes occurred in the common ancestor of vertebrates much earlier than the emergence of eutherians. Thus, our data demonstrate that novel gene function can evolve without de novo gene duplication event.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping