The chromatin of the CD23b locus is set to a transcriptionally active state by CD40 signaling, leading to recruitment and processivity of POLII. (A) QChIP assays were performed using anti-pan-Histone 3 acetylated, anti-pan-Histone 4 acetylated and antiactin antibodies in Ramos cells treated with CD40L during 0 (□), 30 minutes (), and 2 hours (■). QPCR was performed to detect the abundance of CD23b promoter sequence as in Figure 2. The y-axis represents the percentage enrichment by each antibody relative to input. (B) QChIP was performed at the indicated time points using RNA POLII antibodies to detect the abundance of POLII at the CD23b promoter, exon1 and exon 4. The y-axis represents the percentage enrichment of the amplicons relative to input. The result shows increase occupancy by POLII at exon 1 and exon 4 after CD40L exposure, consistent with active transcription of the gene. Each experiment was carried out in duplicate. Error bars represent SEM.