Discovery And Mechanism Of Small Molecule Regulator Targeting BPTF Bromodomain

Histone acetylation modifications can be specifically recognized by BRD family proteins,followed by recruiting relevant chromatin remodeling factors and transcription factors to specific gene transcription sites,which are essential for regulating downstream gene expression.Abnormal expression and activation of BRD family proteins are associated with the development and progression of many diseases such as obesity,HIV,malignant cancer and inflammation.To date,plenty of small molecule inhibitors targeting BRD family proteins have been developed for the treatment of related diseases and to further explore the relevant biological functions.BPTF,a bromodomain-containing protein,plays a crucial role in the regulation of downstream gene expression through the specific recognition of lysine acetylation on bulk histones.The dysfunction of BPTF is closely involved with the development and progression of many human diseases,especially cancer.Therefore,BPTF bromodomain has become a promising drug target for epigenetic cancer therapy.However,unlike BET family inhibitors,few BPTF bromodomain inhibitors have been reported.In this study,by integrating docking-based virtual screening with biochemical analysis,the in-house compound library was virtually screened to obtain a series of candidate compounds based on knowledge of computer-aided drug design.We have developed a high-throughput HTRF screening platform to conduct in vitro activity screening of candidate compounds and confirmed that DCB29 has a certain inhibitory activity on BPTF BRD.Next,the inhibitory activity of the compound was further confirmed by an HTRF binding assay,and the IC50 value of the half inhibitory concentration was 13.2 ± 1.6 ?mol/L.A series of DCB29 derivatives were obtained by 2D similarity search and their inhibitory activities were determined.The structure-activity relationship was analyzed based on inhibitory activities of derivatives and molecular docking results.The binding mode between DCB29 and BPTF BRD was further verified by experiments such as nuclear magnetic resonance and surface plasmon resonance.Molecular docking simulation revealed that DCB29 occupies a pocket of the acetylated H4 peptide substrate,indicating that the compound is a dual substrate competitive inhibitor.In conclusion,DCB29 has great potential as a novel selective BPTF BRD inhibitor in related biological research and the further optimization development of medicinal chemistry.