Figure 1. ChIP results obtained with the Diagenode antibody directed against H2BK15ac ChIP assays were performed using human HeLa cells, the Diagenode antibody against H2BK15ac (Cat. No. C15410220) and optimized PCR primer sets for qPCR. ChIP was performed with the “iDeal ChIP-seq” kit (Cat. No. C01010051), using sheared chromatin from 1.5 million cells. A titration of the antibody consisting of 0.5, 1, 2 and, 5 μg per ChIP experiment was analysed. IgG (1 μg/IP) was used as negative IP control. QPCR was performed with primers for a region approximately 1 kb upstream of the GAPDH and ACTB promoters, used as positive controls, and for the coding region of the inactive MYOD1 gene and the Sat2 satellite repeat, used as negative controls. Figure 1 shows the recovery, expressed as a % of input (the relative amount of immunoprecipitated DNA compared to input DNA after qPCR analysis).
Figure 2. ChIP-seq results obtained with the Diagenode antibody directed against H2BK15ac ChIP was performed on sheared chromatin from 1.5 million HeLaS3 cells using 2 μg of the Diagenode antibody against H2BK12ac (Cat. No. C15410220) as described above. The IP’d DNA was subsequently analysed on an Illumina HiSeq. Library preparation, cluster generation and sequencing were performed according to the manufacturer’s instructions. The 51 bp tags were aligned to the human genome using the BWA algorithm. Figure 2 shows the enrichment along the complete sequence and a 1 Mb region of the X-chromosome (fig 2A and B) and in genomic regions of chromosome 7, surrounding the ACTB gene, and of chromosome 12, surrounding the GAPDH gene (fig 2C and D). The position of the amplicon used for ChIP-qPCR is indicated by an arrow.
Figure 3. Determination of the antibody titer To determine the titer of the antibody, an ELISA was performed using a serial dilution of the Diagenode antibody directed against H2BK15ac (Cat. No. C15410220) in antigen coated wells. The antigen used was a peptide containing the histone modification of interest. By plotting the absorbance against the antibody dilution (Figure 3), the titer of the antibody was estimated to be 1:29,700.
Figure 4. Cross reactivity tests using the Diagenode antibody directed against H2BK15ac To test the cross reactivity of the Diagenode antibody against H2BK15ac (Cat. No. C15410220), a Dot Blot analysis was performed with peptides containing other histone modifications and the unmodified H2B. One hundred to 0.2 pmol of the respective peptides were spotted on a membrane. The antibody was used at a dilution of 1:20,000. Figure 4 shows a high specificity of the antibody for the modification of interest.
Figure 5. Western blot analysis using the Diagenode antibody directed against H2BK15ac Western blot was performed on whole cell (25 μg, lane 1) and histone extracts (15 μg, lane 2) from HeLa cells, and on 1 μg of recombinant histone H2A, H2B, H3 and H4 (lane 3, 4, 5 and 6, respectively) using the Diagenode antibody against H2BK15ac (Cat. No. C15410220). The antibody was diluted 1:500 in TBS-Tween containing 5% skimmed milk. The marker (in kDa) is shown on the left.