Normal mouse or rabbit igg

ChIP assay was performed as described previously40 (link). Crosslinked, sonicated chromatin was precleared before being incubated with 2.5 μg of the indicated antibodies and rotated at 4 °C overnight. Normal mouse or rabbit IgG (Millipore) was used for the mock immunoprecipitation. After extensive washes, immunocomplexes were treated with Proteinase K and decrosslinked. Bound DNA in the precipitates, as well as input DNA (1/10 fragmented chromatin), was extracted, purified, and subjected to real-time PCR analysis using primers corresponding to a region of the repo promoter (−1,337 to −1,138; forward primer, 5′-ATCTGGCCAAAAGGTCACAC-3′; reverse primer, 5′-CTCATGAGGGTGGTTCCATT-3′). Real-time PCRs were conducted on the Bio-Rad iQ5 Gradient Real-Time PCR system, using the 2 × SYBR-Green Master mix (Bio-Rad, USA). Results were corrected for non-specific binding to IgG (whose values were considered as 1 and not shown in the bar graphs). Triplicate PCRs for each sample were carried out.