Figure 4.

Chromatin IP by using anti-acetylated histone antibody to measure histone acetylation at silent loci. (A) Chromatin IP was used to investigate the acetylation state of the histones at the telomeres in mutants 261 and 275. Threefold dilutions of anti-acetylated H3 and anti-acetylated H4 IP DNA were probed for telomeres by using PCR primers corresponding to the telomere on the right arm of chromosome VI. (B) IP DNA described above was blotted to a membrane by using a slot blot apparatus. The DNA was then probed for rDNA sequences to test the level of acetylation of histone H3 and H4 at the rDNA in the mutant strains.