Figure 6From: Roles for common MLL/COMPASS subunits and the 19S proteasome in regulating CIITA pIV and MHC class II gene expression and promoter methylationH3K27me3 is enhanced upon Sug1 knockdown. (a) Sug1 siRNA efficiently decreases endogenous Sug1. HeLa cells were transfected with control or Sug1-specific siRNA, harvested and subjected to western blot analysis for (top) endogenous Sug1 and (bottom) endogenous tubulin. (b-d) H3K27me3 is elevated at cytokine-inducible genes upon diminished Sug1 expression. ChIP assays were carried out in HeLa cells stimulated with IFN-γ for 0 to 18 hours. Lysates were immunoprecipitated with control or endogenous H3K27me3 antibody. Associated DNA was isolated and analyzed as in Figure 2 using primers and probe spanning (b) CIITA pIV, (c) the MHC-II proximal promoter and (d) the GAPDH promoter. Data are presented as percentage input. IgG isotype control values were 0.003 ± 0.001 (CIITA pIV), 0.08 ± 0.02 (MHC-II promoter) and 0.01 ± 0.005 (GAPDH promoter). Values represent mean ± SEM of (n = 3) independent experiments.Back to article page