Gadd45b and N-Methyl-d-Aspartate Induced DNA Demethylation in Postmitotic Neurons

Abstract

Aim: In nondividing neurons examine the role of Gadd45b in active 5-methylcytosine (5MC) and 5-hydroxymethylcytosine (5HMC) removal at a gene promoter highly implicated in mental illnesses and cognition, Bdnf. Materials & methods: Mouse primary cortical neuronal cultures with and without Gadd45b siRNA transfection were treated with N-methyl-d-aspartate (NMDA). Expression changes of genes reportedly involved in DNA demethylation, Bdnf mRNA and protein and 5MC and 5HMC at Bdnf promoters were measured. Results: Gadd45b siRNA transfection in neurons abolishes the NMDA-induced increase in Bdnf IXa mRNA and reductions in 5MC and 5HMC at the Bdnf IXa promoter. Conclusion: These results contribute to our understanding of DNA demethylation mechanisms in neurons, and its role in regulating NMDA responsive genes implicated in mental illnesses.

Keywords::

• alcoholism
• CpG
• epigenetic
• histone
• schizophrenia

Acknowledgement

The authors thank X Zhang and M Sharma for their technical assistance.

Financial & competing interests disclosure

This work was supported by the Department of Veterans Affairs Career Development Award (CDA-2) (IK2BX001650) (DP Gavin), Merit Review Grant; Research Career Scientist award (SC Pandey), and VHA (I01BX001819) (M Guizzetti), and NIH/National Institute on Alcohol Abuse and Alcoholism Grants (NIAAA) (AA-010005) (SC Pandey), (AA021876) (M Guizzetti), and NARSAD Young Investigator Award donation from The Family of Joseph M. Evans (DP Gavin). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Ethical conduct of research

The authors state that they have obtained appropriate institutional review board approval or have followed the principles outlined in the Declaration of Helsinki for all human or animal experimental investigations. In addition, for investigations involving human subjects, informed consent has been obtained from the participants involved.

Additional information

Funding

This work was supported by the Department of Veterans Affairs Career Development Award (CDA-2) (IK2BX001650) (DP Gavin), Merit Review Grant; Research Career Scientist award (SC Pandey), and VHA (I01BX001819) (M Guizzetti), and NIH/National Institute on Alcohol Abuse and Alcoholism Grants (NIAAA) (AA-010005) (SC Pandey), (AA021876) (M Guizzetti), and NARSAD Young Investigator Award donation from The Family of Joseph M. Evans (DP Gavin). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed. No writing assistance was utilized in the production of this manuscript.