Comparative environmental epigenomics in wildlife
Epigenetic changes function as flexible mechanisms to increase a species' adaptability to environmental changes, but past studies have focused mostly on maternal effects. Here we study parental transmitted epigenetic responses and ask also if different environmental changes invoke different or similar responses.
|Involved Department(s):||Dept Evolutionary Genetics, Dept Evolutionary Ecology
|Leibniz-IZW Project Leader(s):||Alexandra Weyrich (Dept Evolutionary Genetics)|
|Leibniz-IZW Project Team:||Jörns Fickel, Dorina Lenz, Selma Yasar (all: Dept Evolutionary Genetics), Sylvia Ortmann, Katharina T. Schrapers (geb. Hille) (all: Dept Evolutionary Ecology)|
|Consortium Partner(s):||Weizmann Institute of Science (Israel)|
|Current Funding Organisation:||Leibniz Competition|
|Understanding traits and evolutionary adaptations|
|Understanding wildlife health and disturbed homeostasis|
|Understanding the environmental context|
|Developing theories, methods, and tools|
Epigenetic modifications are a mechanism conveying environmental information to subsequent generations via paternal germ lines. Research on epigenetic responses to environmental changes in wild mammals has been widely neglected. But not only that, neither have studies been carried out that compare responses to changes of different environmental factors nor have there been studies regarding the responses of different organs and tissues to the same environmental change. In addition, past studies have focused mostly on maternal effects. Here we study paternally transmitted epigenetic responses (in our case changes in DNA methylation patterns) and ask also if different environmental changes invoke different or similar responses.
This was done by exposing adult male wild guinea pigs (Cavia aperea) for two months (the time of a full spermatogenesis cycle) to either a protein-reduced diet or to a 10 °C increase in ambient temperature. Prior to this exposure and right after these males were allowed to reproduce and the resulting male offspring was studied for its DNA methylation pattern. A specific method, called reduced representation bisulfite sequencing (RRBS) was applied, allowing the position-specific identification of methyl-cytosines. This high, single nucleotide resolution led to the detection of regions that were differentially methylated between sons sired before (control) and after the treatment of the fathers.
By comparing the outcome of the two different treatments (changed diet composition vs. increased ambient temperature) we obtained both expected and unexpected results. According to our expectations we found a highly specific epigenetic response reflected in genes involved in specific metabolic pathways depending on the environmental factor that had changed. Unexpected, however, was the finding of genes that had been epigenetically modified in both groups and in the same way. Thus their modification was independent of the environmental factor that had undergone changes. In our view the latter reflects a more general response to changes in outer stimuli, independent of the type of factor that had changed.
Our results indicate that fathers prepared their offspring for experienced environmental changes by paternally inherited epigenetic modifications, suggesting a strong paternal contribution to adaptive processes.
Epigenetics – Treat yourself well!
Guerrero TP, Fickel J, Benhaiem S, Weyrich A (2020) Epigenomics and gene regulation in mammalian social systems. Invited to special issue on “Social behavior and evolution in the omics era” in CURR ZOOL, 66 (3), 307–319, doi:10.1093/cz/zoaa005
Weyrich A, Lenz D and Fickel J (2019) Environmental change-dependent transgenerational epigenetic response. Invited to special issue on “Epigenetics and Adaptation” in Genes 10(1), 4, doi: 10.3390/genes10010004
Weyrich A, Jeschek M, Schrapers KT, Lenz D, Chung TH, Rübensam K, Yasar S, Schneemann M, Ortmann S, Jewgenow K & Fickel J (2018) Diet changes alter paternally inherited epigenetic pattern in male wild guinea pigs. Invited to Environmental epigenetics, 4(2), dvy011
Weyrich A, Lenz D, Jeschek M, Chung TH, Rübensam K, Göritz K, Jewgenow K, Fickel J (2016) Paternal intergenerational epigenetic response to heat exposure in male wild guinea. Invited to special issue on “Epigenetic Studies in Ecology and Evolution” in Molecular Ecology, doi: 10.1111/mec.13494
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