GSK4027 is a potent and selective chemical probe for the PCAF/GCN5 bromodomain. GSK4027 has PCAF TR-FRET pIC50 = 7.4 ; PCAF BROMOscan pKi = 8.9; GCN5 BROMOscan pKi = 8.9; PCAF NanoBRET pIC50 =7.2; BRD4 BD1 TR-FRET pIC50 < 4.3. GSK4027 shows high potency for the PCAF/GCN5 bromodomain, high solubility, cellular target engagement, and ≥18000-fold selectivity over the BET family, together with ≥70-fold selectivity over the wider bromodomain families. p300/CREB binding protein associated factor (PCAF/KAT2B) and general control nonderepressible 5 (GCN5/KAT2A) are multidomain proteins that have been implicated in retroviral infection, inflammation pathways, and cancer development.
