Sex- and brain region-specific patterns of gene expression associated with socially-mediated puberty in a eusocial mammal

PLoS One. 2018 Feb 23;13(2):e0193417. doi: 10.1371/journal.pone.0193417. eCollection 2018.

Abstract

The social environment can alter pubertal timing through neuroendocrine mechanisms that are not fully understood; it is thought that stress hormones (e.g., glucocorticoids or corticotropin-releasing hormone) influence the hypothalamic-pituitary-gonadal axis to inhibit puberty. Here, we use the eusocial naked mole-rat, a unique species in which social interactions in a colony (i.e. dominance of a breeding female) suppress puberty in subordinate animals. Removing subordinate naked mole-rats from this social context initiates puberty, allowing for experimental control of pubertal timing. The present study quantified gene expression for reproduction- and stress-relevant genes acting upstream of gonadotropin-releasing hormone in brain regions with reproductive and social functions in pre-pubertal, post-pubertal, and opposite sex-paired animals (which are in various stages of pubertal transition). Results indicate sex differences in patterns of neural gene expression. Known functions of genes in brain suggest stress as a key contributing factor in regulating male pubertal delay. Network analysis implicates neurokinin B (Tac3) in the arcuate nucleus of the hypothalamus as a key node in this pathway. Results also suggest an unappreciated role for the nucleus accumbens in regulating puberty.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Body Weight / genetics
  • Brain / metabolism*
  • Female
  • Gene Expression Profiling
  • Male
  • Mole Rats / blood
  • Mole Rats / genetics*
  • Mole Rats / growth & development*
  • Organ Specificity
  • Sex Characteristics*
  • Sexual Maturation / genetics*
  • Social Behavior*
  • Steroids / blood

Substances

  • Steroids

Grants and funding

This work was funded by a NSERC Discovery Grant (402633) and Ontario Early Researcher Award to MMH, a NSERC Discovery Grant (312458) to DAM, a NSERC Accelerator Grant (498391) to IBZ and a NSERC (http://nserc-crsng.gc.ca) USRA and CGS M to MFM. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.