Mustoe Aaryn, Taylor Jack H, French Jeffrey A
Program in Neuroscience and Behavior, University of Nebraska at Omaha, Omaha, Nebraska, USA.
Integr Zool. 2018 Nov;13(6):634-654. doi: 10.1111/1749-4877.12318.
Oxytocin (OT) is a hypothalamic nonapeptide that mediates a host of physiological and behavioral processes including reproductive physiology and social attachments. While the OT sequence structure is highly conserved among mammals, New World monkeys (NWMs) represent an unusual "hot spot" in OT structure variability among mammals. At least 6 distinct OT ligand variants among NWMs exist, yet it is currently unclear whether these evolved structural changes result in meaningful functional consequences. NWMs offer a new area to explore how these modifications to OT and its canonical G-protein coupled OT receptor (OTR) may mediate specific cellular, physiological and behavioral outcomes. In this review, we highlight relationships between OT ligand and OTR structural variability, specifically examining coevolution between OT ligands, OTRs, and physiological and behavioral phenotypes across NWMs. We consider whether these evolved modifications to the OT structure alter pharmacological profiles at human and marmoset OTRs, including changes to receptor binding, intracellular signaling and receptor internalization. Finally, we evaluate whether exogenous manipulation using OT variants in marmoset monkeys differentially enhance or impair behavioral processes involved in social relationships between pairmates, opposite-sex strangers, and parents and their offspring. Overall, it appears that changes to OT ligands in NWMs result in important changes ranging from cellular signaling to broad measures of social behavior.
催产素（OT）是一种下丘脑九肽，介导一系列生理和行为过程，包括生殖生理和社会依恋。虽然OT的序列结构在哺乳动物中高度保守，但新大陆猴（NWM）是哺乳动物中OT结构变异性的一个不寻常的“热点”。NWM中至少存在6种不同的OT配体变体，但目前尚不清楚这些进化的结构变化是否会导致有意义的功能后果。NWM为探索对OT及其经典G蛋白偶联OT受体（OTR）的这些修饰如何介导特定的细胞、生理和行为结果提供了一个新领域。在这篇综述中，我们强调了OT配体和OTR结构变异性之间的关系，特别研究了NWM中OT配体、OTR以及生理和行为表型之间的共同进化。我们考虑这些对OT结构的进化修饰是否会改变人类和狨猴OTR的药理学特性，包括受体结合、细胞内信号传导和受体内化的变化。最后，我们评估在狨猴中使用OT变体进行外源操作是否会差异性地增强或损害伴侣、异性陌生人以及父母与后代之间社会关系中涉及的行为过程。总体而言，NWM中OT配体的变化似乎导致了从细胞信号传导到广泛社会行为测量的重要变化。
