Bisulfite sequencing with Daphnia highlights a role for epigenetics in regulating stress response to Microcystis through preferential differential methylation of serine and threonine amino acids

Research output: Contribution to journalArticle


  • Jana Asselman
  • Dieter IM De Coninck
  • Eline Beert
  • Colin R Janssen
  • Michael E Pfrender
  • Ellen Decaestecker
  • Karel AC De Schamphelaere

Colleges, School and Institutes

External organisations

  • Laboratory for Environmental Toxicology and Aquatic Ecology (GhEnToxLab), Ghent University, Belgium
  • Laboratory of Aquatic Biology, KU Leuven–Kulak, Kortrijk, Belgium
  • Department of Biological Sciences, University of Notre Dame, Notre Dame, IN, USA


Little is known about the influence that environmental stressors may have on genome-wide methylation patterns, and to what extent epigenetics may be involved in environmental stress response. Yet, studies of methylation patterns under stress could provide crucial insights on stress response and toxicity pathways. Here, we focus on genome-wide methylation patterns in the micro-crustacean Daphnia magna, a model organism in ecotoxicology and risk assessment, exposed to the toxic cyanobacterium Microcystis aeruginosa. Bisulfite sequencing of exposed and control animals highlighted differential methylation patterns in Daphnia upon exposure to Microcystis primarily in exonic regions. These patterns are enriched for serine/threonine amino acid codons and genes related to protein synthesis, transport and degradation. Furthermore, we observed that genes with differential methylation corresponded well with genes susceptible to alternative splicing in response to Microcystis stress. Overall, our results suggest a complex mechanistic response in Daphnia characterized by interactions between DNA methylation and gene regulation mechanisms. These results underscore that DNA methylation is modulated by environmental stress and can also be an integral part of the toxicity response in our study species


Original languageEnglish
Pages (from-to)924–931
JournalEnvironmental Science & Technology
Issue number2
Early online date16 Dec 2016
Publication statusPublished - 2017