DNA methyltransferase 1 regulates reelin mRNA expression in mouse primary cortical cultures
AUTOR(ES)
Noh, Jai Sung
FONTE
National Academy of Sciences
RESUMO
The polygenic nature of complex psychiatric disorders suggests a common pathway that may be involved in the down-regulation of multiple genes through an epigenetic mechanism. To investigate the role of methylation in down-regulating the expression of mRNAs that may be associated with the schizophrenia phenotype, we have adopted a cell-culture model amenable to this line of investigation. We have administered methionine (2 mM) to primary cultures of cortical neurons prepared from embryonic day 16 mice and show that this treatment down-regulated reelin and glutamic acid decarboxylase 67 (GAD67) mRNA expression but not that corresponding to neuron-specific enolase mRNA. Moreover, methionine increased methylation of the reelin promoter, suggesting a possible mechanism for the observed change. These cultures contain a mixed population of neurons and glia. Approximately 83% of the neurons are GABAergic based on GAD immunoreactivity, and these neurons coexpress high levels of reelin and DNA methyltransferase (Dnmt) 1 immunoreactivity. To examine whether Dnmt1 regulates reelin gene expression, we used an antisense approach to reduce (knock down) Dnmt1 expression. The reduced Dnmt1 mRNA and protein were accompanied by increased reelin mRNA expression. More importantly, the Dnmt1 knockdown blocked the methionine-induced reelin and GAD67 mRNA down-regulation. These data support the hypothesis that the reduced amounts of reelin and GAD67 mRNAs documented in postmortem schizophrenia brain may be the consequence of a Dnmt1-mediated hypermethylation of the corresponding promoters.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=547890Documentos Relacionados
- A reelin–integrin receptor interaction regulates Arc mRNA translation in synaptoneurosomes
- Growth hormone-releasing factor regulates growth hormone mRNA in primary cultures of rat pituitary cells.
- Expression of hepatocyte growth factor receptor (c-met) mRNA in primary cultures of human hepatocytes
- DNA-methyltransferase 1 mRNA is selectively overexpressed in telencephalic GABAergic interneurons of schizophrenia brains
- The 5′ stem–loop regulates expression of collagen α1(I) mRNA in mouse fibroblasts cultured in a three-dimensional matrix