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DNA methylation, which can change within‐individuals over time and regulate gene expression, is important to many aspects of avian biology. It is particularly important in avian responses to various stressors associated with introductions, such as infection and environmental changes. However, it remains unclear whether native and introduced bird populations differ in their epigenetic responses to stressors, and how DNA methylation may contribute to the success of non‐native populations because of the limited availability of epigenetic studies. To address this knowledge gap, we used epiRADseq to investigate changes in DNA methylation within‐individual house sparrowsPasser domesticusprior to and eight hours after a simulated bacterial infection. We compare wild‐caught house sparrows from introduced populations with those from native populations, assessing the number of genomic locations that exhibit changes in methylation, the magnitude of those changes, and the variance among individuals. Our results show that individuals from introduced populations experience more widespread changes in DNA methylation, with greater magnitude and higher variance, compared to their counterparts from native populations. These findings suggest that DNA methylation plays a significant role in an individual's response to infection. They also indicate that individuals from introduced populations may exhibit distinct epigenetic responses compared to their native counterparts, consistent with the concept of epigenetic buffering.
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HPA flexibility and FKBP5 : promising physiological targets for conservation
Hypothalamic–pituitary–adrenal axis (HPA) flexibility is an emerging concept recognizing that individuals that will cope best with stressors will probably be those using their hormones in the most adaptive way. The HPA flexibility concept considers glucocorticoids as molecules that convey information about the environment from the brain to the body so that the organismal phenotype comes to complement prevailing conditions. In this context, FKBP5 protein appears to set the extent to which circulating glucocorticoid concentrations can vary within and across stressors. Thus,FKBP5expression, and the HPA flexibility it causes, seem to represent an individual's ability to regulate its hormones to orchestrate organismal responses to stressors. AsFKBP5expression can also be easily measured in blood, it could be a worthy target of conservation-oriented research attention. We first review the known and likely roles of HPA flexibility and FKBP5 in wildlife. We then describe putative genetic, environmental and epigenetic causes of variation in HPA flexibility andFKBP5expression among and within individuals. Finally, we hypothesize how HPA flexibility andFKBP5expression should affect organismal fitness and hence population viability in response to human-induced rapid environmental changes, particularly urbanization. This article is part of the theme issue ‘Endocrine responses to environmental variation: conceptual approaches and recent developments’.
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- PAR ID:
- 10505047
- Publisher / Repository:
- The Royal Society
- Date Published:
- Journal Name:
- Philosophical Transactions of the Royal Society B: Biological Sciences
- Volume:
- 379
- Issue:
- 1898
- ISSN:
- 0962-8436
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1098/rstb.2022.0512
