Expression of Data from EHMT1 siRNA transfected HeLa cell treated with TNF

We used microarrays to detail the global programme of gene expression to identify TNF-induced genes that are negatively regulated by EHMT1 Transcriptional homeostasis relies on the balance between positive and negative regulation of gene transcription. Methylation of histone H3 lysine 9 (H3K9) is commonly correlated with gene repression. Here, we report that a euchromatic H3K9 methyltransferase, EHTM1, functions as a negative regulator in both the NF-κB- and type I interferon-mediated gene induction pathways. EHMT1 catalyzes H3K9 methylation at promoters of NF-κB target genes. Moreover, EHMT1 interacts with p50 and, surprisingly, p50 appears to repress the expression of type I interferon genes and genes activated by type I interferons by recruiting EHMT1 to catalyze H3K9 methylation at their promoter regions. Silencing the expression of EHMT1 by RNA interference enhances expression of a subset NF-κB regulated genes, augments interferon production and augments antiviral immunity. HeLa cells were double-transfected with control or EHMT1 specific siRNAs. The cells were then treated with or without TNFa for 2 hours followed by RNA extraction and hybridization on Affymetrix microarrays.