I have some questions about Histone modifications ChIPseq.
1: why are H3K27ac peaks broad?
2: People use H3K27ac or H3K4me1 peaks to define enhancers. I thought enhancers and promoters are open chromatin regions which are Neuclesome Fragment Regions. Why do we use H3K27ac or H3K4me1 to denote enhancers?
3: It is reasonable to intersect H3K27ac peaks with ATACseq to identify putative transcription factors?