CBP/p300

CBP/p300 are histone acetyltransferase transcriptional coactivators that regulate gene expression by acetylating histones and transcription factors^[1]. Mechanistically, enhancer activity depends on CBP/P300 bromodomain-dependent H3K27ac, linking chromatin acetylation to active regulatory elements^[2]. In cell-cycle-synchronized cells, ChIP-seq showed that p300 and CBP share many targets but also display significant differences in binding levels and target regions, supporting non-identical isoform functions^[3]. In disease models, CBP30 inhibited IL-17A production in primary human cells and Th17 responses from ankylosing spondylitis and psoriatic arthritis patients^[4]. For experimental applications, I-CBP112 impaired leukemia-initiating self-renewal cells in vitro and in vivo without significant cytotoxicity^[5]. The catalytic inhibitor A-485 competes with acetyl-CoA at p300/CBP and selectively inhibited proliferation in hematological malignancies and androgen receptor-positive prostate cancer models^[6].- CBP/p300 studies should measure enhancer H3K27ac, transcription-factor recruitment, and isoform-specific occupancy.- Bromodomain inhibitors support inflammatory, leukemia, and enhancer-dependency experiments with measurable transcriptional outputs.- Catalytic inhibitors such as A-485 enable direct testing of acetyltransferase-dependent tumor programs.