FIGURE 2.

Nerve injury consistently increases H3K9me2 levels at the Oprm1 promoter in the DRG. A–C, ChIP-PCR quantification data shows the enrichment of histones H3K4me3, H3K9ac, H3K9me2, and H3K27me3 at the three different promoter regions of Oprm1: −43/+63 bp (around the TSS, A), −411/−302 bp (upstream of the TSS, B), and +376/+495 bp (downstream of the TSS, C). The ipsilateral L5 and L6 DRGs were obtained from sham and SNL rats 21 days after surgery (n = 7 independent experiments with 14 rats/group). Data were normalized to the total H3 values and presented as means ± S.E. *, p < 0.05; **, p < 0.01 compared with the sham group (Mann-Whitney test).