Data from: Exposure to a competitive social environment activates an epigenetic mechanism that limits pheomelanin synthesis in zebra finches

Competitive environments promote high testosterone levels, oxidative
stress and, consequently, impair cellular homeostasis. The regulation of
genes involved in the synthesis of the pigment pheomelanin in melanocytes
seems to help to maintain homeostasis against environmental oxidative
stress. Here, we experimentally increased social interactions in some
zebra finch Taeniopygia guttata males by keeping them in groups of six
birds during feather growth, while others were kept alone, to test if
melanocytes show epigenetic lability under a competitive social
environment. As these changes may depend on the oxidative status, we
administrated buthionine sulfoximine (BSO) to decrease the antioxidant
capacity of some birds. The competitive environment downregulated a gene
involved in pheomelanin synthesis (Slc7a11) by changing the level of DNA
methylation in feather melanocytes. In other genes involved in pheomelanin
synthesis (Slc45a2, MC1R and AGRP), DNA methylation was also affected, but
no changes in expression were detected. The exposure to the competitive
environment did not affect systemic oxidative stress and damage,
indicating that a protective epigenetic mechanism that changes the
expression of Slc7a11 may have been activated. However, no changes on the
pigmentation phenotype of birds were found, likely due to the short
duration or low intensity of the competitive environment. BSO treatment
did not affect the epigenetic mechanism, suggesting that the antioxidant
capacity of birds was high enough to deal with the competitive
environment. An epigenetic mechanism limiting pheomelanin synthesis gets
therefore activated under exposure to a competitive environment in male
zebra finches, which may help avoiding damage caused by competitive
interactions.