Olfactory Receptor Subgenomes Linked with Broad Ecological Adaptations in Sauropsida.

Khan, Imran

Yang, Zhikai

Maldonado, Emanuel

Li, Cai

Zhang, Guojie

Gilbert, M Thomas P

Jarvis, Erich D

O'Brien, Stephen J

Johnson, Warren E

Antunes, Agostinho

United States

2015-12-11T01:20:03Z

2015-11

Olfactory receptors (ORs) govern a prime sensory function. Extant birds have distinct olfactory abilities, but the molecular mechanisms underlining diversification and specialization remain mostly unknown. We explored OR diversity in 48 phylogenetic and ecologically diverse birds and 2 reptiles (alligator and green sea turtle). OR subgenomes showed species- and lineage-specific variation related with ecological requirements. Overall 1,953 OR genes were identified in reptiles and 16,503 in birds. The two reptiles had larger OR gene repertoires (989 and 964 genes, respectively) than birds (182-688 genes). Overall, birds had more pseudogenes (7,855) than intact genes (1,944). The alligator had significantly more functional genes than sea turtle, likely because of distinct foraging habits. We found rapid species-specific expansion and positive selection in OR14 (detects hydrophobic compounds) in birds and in OR51 and OR52 (detect hydrophilic compounds) in sea turtle, suggestive of terrestrial and aquatic adaptations, respectively. Ecological partitioning among birds of prey, water birds, land birds, and vocal learners showed that diverse ecological factors determined olfactory ability and influenced corresponding olfactory-receptor subgenome. OR5/8/9 was expanded in predatory birds and alligator, suggesting adaptive specialization for carnivory. OR families 2/13, 51, and 52 were correlated with aquatic adaptations (water birds), OR families 6 and 10 were more pronounced in vocal-learning birds, whereas most specialized land birds had an expanded OR family 14. Olfactory bulb ratio (OBR) and OR gene repertoire were correlated. Birds that forage for prey (carnivores/piscivores) had relatively complex OBR and OR gene repertoires compared with modern birds, including passerines, perhaps due to highly developed cognitive capacities facilitating foraging innovations.

http://www.ncbi.nlm.nih.gov/pubmed/26219582

msv155

1537-1719

https://hdl.handle.net/10161/11139

eng

Oxford University Press (OUP)

Mol Biol Evol

10.1093/molbev/msv155

adaptation

birds

olfactory receptors

selection

Acclimatization

Adaptation, Physiological

Alligators and Crocodiles

Animals

Birds

Ecology

Evolution, Molecular

Genetic Variation

Genome

Phylogeny

Receptors, Odorant

Reptiles

Sequence Analysis, DNA

Species Specificity

Turtles

Olfactory Receptor Subgenomes Linked with Broad Ecological Adaptations in Sauropsida.

Journal article

http://www.ncbi.nlm.nih.gov/pubmed/26219582

2832

2843

11

Basic Science Departments

Duke

Duke Institute for Brain Sciences

Institutes and Provost's Academic Units

Neurobiology

School of Medicine

University Institutes and Centers

Published

32