Figure 6.
Chromatin immunoprecipitation (ChIP) to compare histone modifications near telomeres in WT and nst triple mutant strains. Telomeric regions investigated are shown in the schematics at left. Vertical striped bars represent telomeric (TTAGGG)n repeats and horizontal striped bars in A represent Pogo LTRs. Black bars represent open reading frames and are labeled according to the Broad Institute database. Strains N3120 (nst-1+) and N3132 (nst-1RIP1nst-3RIP1nst-5RIP1) show increased acetylation of H3 and H4 and decreased histone methylation at the derepressed hph gene at telomere VR. A-D) Immunoprecipitated chromatin was amplified with primers for the indicated regions, shown as gray bars. Values in the figure indicate enrichment of specific modifications at telomeric regions relative to euchromatic (hH4) regions (A-C). To determine these values bands were quantified using ImageQuant software and ratios were calculated relative to input DNA. D) We also tested a non-telomeric heterochromatic region with methylated DNA (8:F10) [27].