Genetic Diversity in Oxytocin Ligands and Receptors in New World Monkeys

Authors

Dongren Ren, Callitrichid Research Centre, Department of Psychology, University of Nebraska at Omaha; Key Laboratory for Animal Biotechnology of Jiangxi Province and Ministry of Agriculture of China; Department of Biology, University of Nebraska at OmahaFollow
Guoqing Lu, University of Nebraska at Omaha
Hideaki Moriyama, University of Nebraska-LincolnFollow
Aaryn C. Mustoe, Callitrichid Research Centre, Department of Psychology, University of Nebraska at Omaha
Emily B. Harrison, Callitrichid Research Centre, Department of Psychology, University of Nebraska at Omaha; Department of Biology, University of Nebraska at Omaha
Jeffery A. French, University of Nebraska at OmahaFollow

Document Type

Article

Date of this Version

2015

Citation

PLOS ONE, 2015

Comments

U.S. Government work

Abstract

Oxytocin (OXT) is an important neurohypophyseal hormone that influences wide spectrum of reproductive and social processes. Eutherian mammals possess a highly conserved sequence of OXT (Cys-Tyr-Ile-Gln-Asn-Cys-Pro-Leu-Gly). However, in this study, we sequenced the coding region for OXT in 22 species covering all New World monkeys (NWM) genera and clades, and characterize five OXT variants, including consensus mammalian Leu8-OXT, major variant Pro8-OXT, and three previously unreported variants: Ala8-OXT, Thr8-OXT, and Phe2-OXT. Pro8-OXT shows clear structural and physicochemical differences from Leu8-OXT. We report multiple predicted amino acid substitutions in the G protein- coupled OXT receptor (OXTR), especially in the critical N-terminus, which is crucial for OXT recognition and binding. Genera with same Pro8-OXT tend to cluster together on a phylogenetic tree based on OXTR sequence, and we demonstrate significant coevolution between OXT and OXTR. NWM species are characterized by high incidence of social monogamy, and we document an association between OXTR phylogeny and social monogamy. Our results demonstrate remarkable genetic diversity in the NWM OXT/OXTR system, which can provide a foundation for molecular, pharmacological, and behavioral studies of the role of OXT signaling in regulating complex social phenotypes.