Abstract
DNA methylation is a key epigenetic modification of DNA that is catalyzed by DNA methyltransferase (DNMT). Increasing evidence suggests that DNA methylation in neurons regulates synaptic plasticity as well as neuronal network activity. Here, we evaluated DNA methyltransferase 1 (Dnmt1) and Dnmt3a expression in brain tissues of epileptic patients to explore their possible role in epileptogenesis. Tissue samples from temporal neocortices of 25 patients with intractable temporal lobe epilepsy (TLE) and ten histologically normal temporal lobes from control patients were used to detect Dnmt1 and Dnmt3a expression through immunohistochemistry, immunofluorescence, and Western blotting analysis. We found that both Dnmt1 and Dnmt3a expression were principally expressed in the nucleus and the cytoplasm of NeuN-positive neurons, but not in GFAP-positive astrocytes. Levels of the two DNMT proteins were significantly increased in patients with TLE. Our study suggests that DNMT1 and DNMT3a may play a role in the pathogenesis of TLE.
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Acknowledgments
This work was supported by a grant from the National Natural Science Foundation of China (no. 81071039, 81071040). We sincerely thank the patients and their families for their participation in this study.
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Zhu, Q., Wang, L., Zhang, Y. et al. Increased Expression of DNA methyltransferase 1 and 3a in Human Temporal Lobe Epilepsy. J Mol Neurosci 46, 420–426 (2012). https://doi.org/10.1007/s12031-011-9602-7
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DOI: https://doi.org/10.1007/s12031-011-9602-7