Histone H3 Lysine 4 trimethylation (H3K4me3) ChIP-Seq to identify actively transcribing genes and their active promoter regions in the narrower and wider vanes of primary remiges, respectively

Purpose: One goal of this study is to identify actively transcribing genes in the mesenchyme (pulp) corresponding to the narrow (lateral) and wide (medial) vane of primary remiges. The other is to pinpoint the active promoter regions of these genes. 15 primary remige follicles were collected, cut into the lateral and medial halves and shorted treated in 2x CMF to separate epithelium and mesenchyme. The mesenchymal cells were dissociated by 0.35% collagenase digestion. Then we conduct formaldehyde crosslinking, sonication, IP, reverse crosslinking and removal of protein/RNA. The library preparation and sequencing were done at USC epigenome center.