Oxytocin variation and brain region‐specific gene expression in a domesticated avian species

Abstract

The Bengalese finch was domesticated more than 250 years ago from the wild whiterumped munia (WRM). Similar to other domesticated species, Bengalese finches show a reduced fear response and have lower corticosterone levels, compared to WRMs.Bengalese finches and munias also have different song types. Since oxytocin (OT) has been found to be involved in stress coping and auditory processing, we tested whether the OT sequence and brain expression pattern and content differ in wild munias and domesticated Bengalese finches. We sequenced the OT from 10 wild munias and 11 Bengalese finches and identified intra-strain variability in both the untranslated and protein-coding regions of the sequence, with all the latter giving rise to synonymous mutations. Several of these changes fall in specific transcription factor-binding sites, and show either a conserved or a relaxed evolutionary trend in the avian lineage, and in vertebrates in general. Although in situ hybridization in Yasuko Tobari and Constantina Theofanopoulou contributed equally to this work.

Effect of Darkness on Intrinsic Motivation for Undirected Singing in Bengalese Finch (Lonchura striata Domestica): A Comparative Study With Zebra Finch (Taeniopygia guttata)

“…BF is a domesticated strain of the wild ancestor WRM, and a growing body of research suggests that in the course of the domestication process, BFs have acquired behavioral, anatomical, and neuroendocrine changes, including reduced sensitivity to environmental stresses ( Suzuki et al, 2014 ; Suzuki et al, 2021 ; Suzuki and Okanoya, 2021 ; Tobari et al, 2022 ). In particular, BFs exhibit reduced levels of fearfulness related to coping with predation ( Suzuki et al, 2013 ) and lower fecal CORT levels than WRM ( Suzuki et al, 2012 ).…”

The neural distribution of the avian homologue of oxytocin, mesotocin, in two songbird species, the zebra finch and the canary: A potential role in song perception and production

“…The zebra finch exhibits OT mRNA in BNSTm, PVN, and SON, while Bengalese finches ( Lonchura striata var. domestica ) and white‐rumped munias ( Lonchura striata ) have OT mRNA in the SON, PVN, and lateral hypothalamus (Tobari et al., 2022; Vicario et al., 2017). Therefore, OT expression in these areas appears to be shared across avian taxa.…”

“…and white-rumped munias (Lonchura striata) have OT mRNA in the SON, PVN, and lateral hypothalamus (Tobari et al, 2022;Vicario et al, 2017).…”

“…Past immunohistochemical investigations of OT peptide expression in birds were performed utilizing antigens produced in laboratory and that are no longer available (Goossens et al., 1977). More recently, several studies have sequenced the OT gene and characterized the expression of OT mRNA in a limited number of brain regions in songbirds via in situ hybridization (Barth et al., 1997; Tobari et al., 2022; Vicario et al., 2017). The gene for OT has been included in the zebra finch atlas (Tobari et al., 2022; Vicario et al., 2017; Zebra Finch Expression Brain Atlas, n.d.).…”

“…More recently, several studies have sequenced the OT gene and characterized the expression of OT mRNA in a limited number of brain regions in songbirds via in situ hybridization (Barth et al., 1997; Tobari et al., 2022; Vicario et al., 2017). The gene for OT has been included in the zebra finch atlas (Tobari et al., 2022; Vicario et al., 2017; Zebra Finch Expression Brain Atlas, n.d.). However, these studies have not comprehensively mapped the distribution of the mRNA, and the levels of mRNA expression can differ from peptide abundance due to regulatory posttranscriptional processes.…”