Figure 3. Coverage plot of a histone mark, H3K9me3, after repeated cocaine or saline conditions shown in the IGV genome browser( Robinson et al., 2011 ).

Y-axis represents the normalized coverage of DNA fragments enriched by the antibody against H3K9me3. This is a peak of ~9 Kb long located on chromosome 8, which shows reduced binding after chronic cocaine treatment in mouse nucleus accumbens (NAc) ( Maze et al., 2011 ).