A transcription factor pulse can prime chromatin for heritable transcriptional memory [ChIPseq]

To investigate the epigenetic control of long-term transcriptionnal memory (LTTM) we used a trans-differentiation system where Bcell are reprogramed into macrophages upon induction of the transcription factor Cebpa. We performed ChIPseq in untreated Bcells, after 12h of Cebpa induction and after 6days of “wash” of Cebpa, to see if any proteins/histone marks are retained. Genome binding/occupancy of transcription factor Pu1 and histones (H3K4me1/2/3 and H3K27me3) by ChIPseq in uninduced Bcell (Control), after induction Cebpa for 6h (Pulse) and after 6 days of wash (Chase).

为探究长期转录记忆（long-term transcriptionnal memory, LTTM）的表观遗传调控机制，我们采用了转分化系统：在转录因子Cebpa的诱导下，B细胞可被重编程为巨噬细胞。我们分别对未处理的B细胞、经Cebpa诱导12小时的细胞以及Cebpa诱导后洗脱6天的细胞开展了染色质免疫沉淀测序（ChIP-seq）实验，以检测是否存在蛋白质或组蛋白修饰标记的留存情况。此外，我们还在未诱导的B细胞（对照组）、经Cebpa诱导6小时（脉冲处理组）以及洗脱6天（追踪组）的细胞中，通过染色质免疫沉淀测序检测了转录因子Pu1以及组蛋白H3K4me1/2/3、H3K27me3的基因组结合/占据情况。