Figure 3

Dynamic histone acetylation levels adjacent to the transcription start site of NOS3 correlate with impaired placental perfusion and differential NOS3 expression. (A-B) Histone acetylation patterns differed significantly between patients with high- (green line) and low- (red line) NOS3 mRNA levels. Interestingly, levels of H3K9ac (A) as well as H2A.Zac (B) were significantly higher surrounding the transcription start site (TSS). (C-D) The combined illustration of H3K9ac and H2A.Zac patterns—calculated as mean of both fold changes—demonstrated an even more pronounced effect of histone acetylation at the TSS on NOS3 mRNA levels (C) suggesting that both acetylation hallmarks have similar biological consequences. Moreover, the overall level of acetylation around the TSS directly correlated with NOS3 mRNA levels (D). Features of the gene structure cartoon are described in Figure 2. (E-F) H3K9me3 levels adjacent to the TSS were higher in patients with high-NOS3 mRNA levels when compared to patients with low-copy number (E)—except for one patient with low-NOS3 mRNA copy number who also had a high level of H3K9me3 (UC13). At the same time, patients with high-NOS3 mRNA copy number also showed an increase in H3K9me3/S10ph (F).