Novel Inhibitor Discvoery And Mechanism Study Of Histone Acetyltransferase HGCN5

Histone acetylation,one of most common post-translation modification in organism,which catalyzed by histone acetyltransferase?HATs?,is an important mean of regulating gene expression in eukaryote.General control nonrepressed protein 5?GCN5?,one of the most prominent member in HAT family,catalyzes the acetylationg of various transcription factors.Aberrant expression and activation of GCN5 is closely linked with the pathogenesis and progression of several malignant diseases especially cancers.It is a potential target of anticancer drug development.Research for GCN5 inhibitors has been ongoing,but progress has been slow.The present GCN5 inhibitors suffer from poor activity and single chemical skeleton.Therefore,it is of great significance to develop the novel,potent GCN5 inhibitors.In this study,we have established and optimized the AlphaScreen high-throughput screening platform for human GCN5?hGCN5?.Combined with AlphaScreen-based high throughput screening platform,radioactive acetylation and2D-similarity based analogue searching,we discovered the lead compound DC_HG24-01 which could significantly inhibite the in vitro activity of hGCN5 with IC₅₀ value of 3.1+0.2?M.Further surface plasmon resonance?SPR?assays demonstrated its binding to the HAT domain of hGCN5 with the K_D value of 11.6+1.3?M in vitro.Binding pattern analysis suggested DC_HG24-01 occupied the binding pocket of cofactor Ac-CoA.In addition,we have anzlyed the structure-activity relationship of DC_HG24-01 according to radioactive acetylation and computataional docking.The structure-activity relationship could provide more clues for further structural optimization.In the cellular level,DC_HG24-01 could retard cell proliferation in MV4-11cell lines(IC₅₀=28.4+0.8?M),and block the acetylation of H3K14.In addition,DC_HG24-01 lead to cell apoptosis and cell cycle arrest at G1 arrest,which accounted for its antiproliferation activity.In summary,based on combination with AlphaScreen high-throughput screening platform and biological experiments,we found DC_HG24-01,the potent hGCN5inhibitor,which provides new clues for GCN5-related disease treatment and new ideas for the discovery of hGCN5 inhibitors.