Figure 1. Chromatin modifications in Rb1^+/Δ19 osteoblasts.

(A) Telomere Chromatin Condensation Assay (TCCA) in primary osteoblasts. qPCR based assay to measure the loss of telomeric repeats after enzymatic digestion with the nuclease Bal 31 in Rb1^+/+ chromatin (filled squares), Rb1^+/Δ19 chromatin (filled triangles), LV-RB1 chromatin (filled circles in grey), Rb1^+/+ naked DNA (open squares), Rb1^+/Δ19 naked DNA (open triangles) and LV-RB1 naked DNA (open circles). Error bars show standard deviation of 2 biological replicates with 3 technical replicates each at passage 6. (B) Chromatin immunoprecipitation analysis at the telomere level. The histone modification changes in Rb1^+/Δ19 osteoblasts (checked bars) at the telomeres are shown compared to the Rb1^+/+ (open bar). The outcome of the assay is shown for each antibody relative to the input and to the Rb1^+/+ control. Error bars show the mean of 2 biological replicates in 3 consecutive experiments for each antibody. Significances were assessed using Student’s t-test.