Figure 3.

Dynamic Ezh2 association and histone modification at the Ink4a/Arf locus in aging pancreatic islets. (A) A schematic of the mouse Cdkn2a/2b locus that encodes the linked mouse genes Ink4a, Arf, and Ink4b. The relative position of amplicons (1, 2, 3, 4, and 5) used for ChIP assays is marked by black bars. Primer sequences were listed in Supplemental Table 2. ChIP analysis was performed with the indicated amplicons and antibodies recognizing Ezh2 (B), H3K27me3 (C), H3K4me3 (D), H3K9/14Ac (E), H3K9me3 (F), and IgG control (G) in pancreatic islets purified from young (1-mo-old) and old (10∼12-mo-old, Avg. 11 mo) C57BL/6 mice. DNA enrichments are presented as percentages of total input. Three to five independent ChIP experiments were performed for each antibody using separate islet preparations. (*) P < 0.05 for 1 mo versus 11 mo.