Meeting Abstract
Parents can have profound epigenetic effects on offspring fitness. Little, however, is known about the epigenetic impacts of parental care variation in offspring and how such variation may interact with offspring genotype in natural systems. The white-throated sparrow (Zonotrichia albicollis, WTSP) provides an ideal system to investigate the epigenetic effects of parental care in offspring. WTSPs exist in two genetic morphs, tan and white, controlled by a chromosomal inversion. Morphs mate disassortatively, resulting in distinct parental care types: biparental care (tan male x white female) and female-biased care (white male x tan female). Both parental care types produce tan and white morph offspring, offering an opportunity to study how offspring morph interacts with parental care variation. To investigate parental care impacts in WTSP nestlings, we performed RNA-seq on WTSP nestlings experiencing the two parental care types. We find 881 genes differentially expressed (DE) between the two nest types and seven gene co-expression modules correlated with parental care. These modules and DE genes up-regulated in female-biased nests primarily function in metabolic, catabolic, and stress related pathways resulting from the overrepresentation of stress response and proteolysis genes. Nestlings also exhibit morph specific gene expression, driven by both innate immunity genes and strong co-expression of genes located in the chromosomal inversion. However, there is no apparent difference between morphs in their response to parental genotypes. We have demonstrated that differences in parental genotypes alter nestling metabolism and stress. This difference is likely driven by variation in parental care.
