The bromodomain containing protein 9 (BRD9) has been reported as a component of the switch/sucrose non-fermentable (SWI/SNF) brahma-related gene 1-associated factor (BAF) complex, which plays a key role in chromatin remodelling and transcription control [1] although the precise biological role is unknown. The highly homologous bromodomain containing protein 7 (BRD7) is a component of the SWI/SNF polybromo-associated BAF (PBAF) complex and has been proposed as a tumor suppressor [2].
In a collaborative effort Takeda and the SGC have identified and characterised TP-472 as a BRD9/7 probe. This molecule is of a different chemotype to the BRD9/7 probes previously available, has a structurally similar negative control available (TP-472N), has a good PK profile and is suitable for in vivo applications and is synthetically tractable.
TP-472 has excellent potency (BRD9 KD 33nM; BRD7 340nM by ITC), selectivity >30 fold over all other bromodomain family members except BRD7 and is cell active (EC50 320 nM in a BRD9 NanoBRET assay). The negative control TP472N is inactive against other bromodomains (>20uM against BRD9)