Perturbed DNA methylation by sustained overexpression of Gadd45b induces chromatin disorganization, DNA strand breaks and dopaminergic neurondeath in mice

Ravel-Godreuil, C. et al.

Heterochromatin disorganization is a key hallmark of aging and DNA methylation state is currently the main molecular predictor of chronological age. The most frequent neurodegenerative diseases like Parkinson disease and Alzheimer’s disease are age-related but how the aging process and chromatin alterations are linked to neurodegeneration is unknown. Here, we investigated the consequences of viral overexpression of Gadd45b, a multifactorial protein involved in active DNA demethylation, in the midbrain of wild-type mice. Gadd45b overexpression induces global and stable changes in DNA methylation, particularly on gene bodies of genes related to neuronal functions. DNA methylation changes were accompanied by perturbed H3K9me3-marked heterochromatin and increased DNA damage. Prolonged Gadd45b expression resulted in dopaminergic neuron degeneration accompanied by altered expression of candidate genes related to heterochromatin maintenance, DNA methylation or Parkinson disease. Gadd45b overexpression rendered midbrain dopaminergic neurons more vulnerable to acute oxidative stress. Heterochromatin disorganization and DNA demethylation resulted in derepression of mostly young LINE-1 transposable elements, a potential source of DNA damage, prior to Gadd45b-induced neurodegeneration. Our data implicate that alterations in DNA methylation and heterochromatin organization, LINE-1 derepression and DNA damage can represent important contributors in the pathogenic mechanisms of dopaminergic neuron degeneration with potential implications for Parkinson disease.

Premium RRBS Kit
DNA Methylation Profiling (RRBS Service)

Share this article

January, 2021


Products used in this publication

  • default alt
    RRBS service (Reduced Representation Bisulfite ...
  • Methylation kit icon
    Premium RRBS kit V2
  • Methylation kit icon
    Premium RRBS kit V2 x96 RRBS for low DNA amoun...


  • FASEB Biological Methylation: Fundamental Mechanisms
    Porto, Portugal
    Jul 28-Aug 1, 2024


       Site map   |   Contact us   |   Conditions of sales   |   Conditions of purchase   |   Privacy policy