Daily variation in global and local DNA methylation in mouse livers

PLoS One. 2015 Feb 17;10(2):e0118101. doi: 10.1371/journal.pone.0118101. eCollection 2015.

Abstract

DNA methylation is one of the best-characterized epigenetic modifications and has an important biological relevance. Here we showed that global DNA methylation level in mouse livers displayed a daily variation where the peak phases occurred during the end of the day and the lowest level at the beginning of the day in the light-dark or dark-dark cycles. Typical repeat sequence long interspersed nucleotide element-1 (LINE-1) had a similar methylation rhythm to global DNA. DNA methyltransferase 3A (DNMT3A) and ratio of S-adenosylmethionine (SAM) to S-adenosylhomocysteine (SAH) brought a relative forward daily variation to global DNA methylation, and the temporary change in ratio of SAM to SAH had no influence on the DNA methylation level. The rhythm of global DNA methylation was lost and DNA methylation level was increased in Per1-/-Per2-/- double knockout mice, which were in accordance with changes of Dnmt3a mRNA levels and its rhythm. Our results suggest that the daily variation in global DNA methylation was associated with the change of Dnmt3a expression rather than ratio of SAM to SAH.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Circadian Rhythm / genetics*
  • DNA (Cytosine-5-)-Methyltransferases / genetics
  • DNA Methylation / physiology*
  • DNA Methyltransferase 3A
  • DNA-Binding Proteins / genetics
  • Gene Expression Regulation, Enzymologic
  • Gene Knockout Techniques
  • Liver / metabolism*
  • Male
  • Mice
  • Period Circadian Proteins / deficiency
  • Period Circadian Proteins / genetics
  • S-Adenosylhomocysteine / metabolism
  • S-Adenosylmethionine / metabolism

Substances

  • DNA-Binding Proteins
  • Dnmt3a protein, mouse
  • Per1 protein, mouse
  • Per2 protein, mouse
  • Period Circadian Proteins
  • S-Adenosylmethionine
  • S-Adenosylhomocysteine
  • DNA (Cytosine-5-)-Methyltransferases
  • DNA Methyltransferase 3A

Grants and funding

This work was supported by the National Basic Research Program of China (2012CB517505 and 2013CB945203), and the National Science Foundation of China (31171125). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.