HeLa cells were stained with the Bioss antibody against H3K18ac (cat. No. bs-53137R) and with DAPI. Cells were fixed with 4% formaldehyde for 10’ and blocked with PBS/TX-100 containing 5% normal goat serum and 1% BSA. The cells were immunofluorescently labeled with the H3K18ac antibody (left) diluted 1:200 in blocking solution followed by an anti-rabbit antibody conjugated to Alexa488. The middle panel shows staining of the nuclei with DAPI. A merge of the two stainings is shown on the right.


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 Bioss antibody against H3K18ac (cat. No. bs-53137R). The antibody was diluted 1:500 in TBS-Tween containing 5% skimmed milk.


To test the cross-reactivity of the Bioss antibody against H3K18ac (cat. No. bs-53137R), a Dot Blot analysis was performed with peptides containing other histone modifications and the unmodified H3K18. One hundred to 0.2 pmol of the respective peptides were spotted on a membrane. The antibody was used at a dilution of 1:5,000. The figure shows a high specificity of the antibody for the modification of interest.


To determine the titer of the antibody, an ELISA was performed using a serial dilution of the Bioss antibody against H3K18ac (cat. No. bs-53137R). The antigen used was a peptide containing the histone modification of interest. By plotting the absorbance against the antibody dilution, the titer of the antibody was estimated to be 1:4,300.


ChIP was performed as described above using 1 μg of H3K18ac Polyclonal Antibody (cat. No. bs-53137R). The IP’d DNA was subsequently analyzed on an Illumina Genome Analyzer. Library preparation, cluster generation, and sequencing were performed according to the manufacturer’s instructions. The 36 bp tags were aligned to the human genome using the ELAND algorithm. The figure shows the peak distribution along the complete human X-chromosome and a zoom-in to a 600 kb region (figure A and B), and in two regions on chromosome 14 and 3 surrounding the c-fos and EIF4A2 positive control genes (figure C and D).