(1) Background: The objective of this study was to uncover genomic causes of parental
care. Since birds do not lactate and, therefore, do not show the gene expressional
changes required for lactation, we investigate gene expression associated with parenting
in caring and non-caring females in an avian species, the small passerine bird zebra
finch (Taeniopygia guttata). Here, we compare expression patterns in the hypothalamic-septal
region since, previously, we showed that this area is activated in parenting females.
(2) Methods: Transcriptome sequencing was first applied in a dissected part of the
zebra finch brain related to taking care of the nestlings as compared to a control
group of social pairs without nestlings. (3) Results: We found genes differentially
expressed between caring and non-caring females. When introducing a log2fold change
threshold of 1.5, 13 annotated genes were significantly upregulated in breeding pairs,
while 39 annotated genes were downregulated. Significant enrichments of dopamine and
acetylcholine biosynthetic processes were identified among upregulated pathways, while
pro-opiomelanocortin and thyroid hormone pathways were downregulated, suggesting the
importance of these systems in parental care. Network analysis further suggested neuro-immunological
changes in mothers. (4) Conclusions: The results confirm the roles of several hypothesized
major pathways in parental care, whereas novel pathways are also proposed.
