AID-dependent histone acetylation is detected in immunoglobulin S regions - PubMed (original) (raw)

Figure 1.

Histones H3 and H4 become hyperacetylated in 1.B4.B6 cells induced to undergo CSR. GLTs (A) and postswitch transcripts (B) were analyzed by semi-quantitative RT-PCR using cDNA derived from 1.B4.B6 cells that were unstimulated (Un) or activated with LPS+CD40L (L+C) and LPS+CD40L+IL-4 (L+C+IL4) for 48 h and 5 d, respectively. GLT and Aicda PCR products were harvested after 33 cycles (lanes 1, 5, 9), 31 cycles (lanes 2, 6, 10), 29 cycles (lanes 3, 7, 11), and 27 cycles (lanes 4, 8, 12). Gapdh PCR products were harvested after 30 cycles (lanes 1, 5, 9), 28 cycles (lanes 2, 6, 10), 26 cycles (lanes 3, 7, 11), and 24 cycles (lanes 4, 8, 12). (B) Postswitch PCR products were harvested after 33 cycles (lanes 1, 4, 7), 31 cycles (lanes 2, 5, 8), and 29 cycles (lanes 3, 6, 9). Gapdh PCR products were harvested after 30 cycles (lanes 1, 4, 7), 28 cycles (lanes 2, 5, 8), and 26 cycles (lanes 3, 6, 9). (C) A schematic diagram is shown of a generic Ix-S-Cx locus containing the I exon (Ix), an S region, and a constant region gene (Cx). The position of primer sets are indicated by the arrows. (D) Anti-(α)H3Ac or αH4Ac histone antisera were used in ChIP assays performed on nuclei derived from 1.B4.B6 cells that were unstimulated or stimulated with LPS+CD40L and LPS+CD40L+IL-4 for 48 h. The results from five samples derived from three independent experiments are shown with standard deviations. Samples were analyzed in duplicate and averaged. All ChIP PCR values were normalized against ChIP for the Gapdh locus and input DNA in the same sample.