PUBLICATION
Evolutionary dynamics of olfactory receptor genes in fishes and tetrapods
- Authors
- Niimura, Y., and Nei, M.
- ID
- ZDB-PUB-050413-17
- Date
- 2005
- Source
- Proceedings of the National Academy of Sciences of the United States of America 102(17): 6039-6044 (Journal)
- Registered Authors
- Keywords
- birth-and-death evolution; multigene family; vertebrate evolution
- MeSH Terms
-
- Animals
- Biological Evolution*
- Databases, Nucleic Acid
- Databases, Protein
- Fishes/classification
- Fishes/genetics*
- Humans
- Mammals/classification
- Mammals/genetics*
- Olfactory Receptor Neurons/physiology*
- Phylogeny
- PubMed
- 15824306 Full text @ Proc. Natl. Acad. Sci. USA
Citation
Niimura, Y., and Nei, M. (2005) Evolutionary dynamics of olfactory receptor genes in fishes and tetrapods. Proceedings of the National Academy of Sciences of the United States of America. 102(17):6039-6044.
Abstract
Olfaction, which is an important physiological function for the survival of mammals, is controlled by a large multigene family of olfactory receptor (OR) genes. Fishes also have this gene family, but the number of genes is known to be substantially smaller than in mammals. To understand the evolutionary dynamics of OR genes, we conducted a phylogenetic analysis of all functional genes identified from the genome sequences of zebrafish, pufferfish, frogs, chickens, humans, and mice. The results suggested that the most recent common ancestor between fishes and tetrapods had at least nine ancestral OR genes, and all OR genes identified were classified into nine groups, each of which originated from one ancestral gene. Eight of the nine group genes are still observed in current fish species, whereas only two group genes were found from mammalian genomes, showing that the OR gene family in fishes is much more diverse than in mammals. In mammals, however, one group of genes, gamma, expanded enormously, containing approximately 90% of the entire gene family. Interestingly, the gene groups observed in mammals or birds are nearly absent in fishes. The OR gene repertoire in frogs is as diverse as that in fishes, but the expansion of group gamma genes also occurred, indicating that the frog OR gene family has both mammal- and fish-like characters. All of these observations can be explained by the environmental change that organisms have experienced from the time of the common ancestor of all vertebrates to the present.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping