Identification of Transcription Complexes that Contain the Double Bromodomain Protein Brd2 and Chromatin Remodeling Machines

Abstract

We use affinity purification of the double bromodomain protein Brd2 to isolate a multicomponent nuclear complex from cultured cells, and apply mass spectrometry/proteomics methods to identify the participants. We then confirm by immunoblot several transcription co-activators and co-repressors, proteins of the Swi/Snf chromatin remodeling complex, which regulate transcription control of cyclin A. This multiprotein complex is likely to contribute to cell cycle control and play a role in proliferation and cancer. Keywords: bromodomain • multiprotein complexes • affinity chromatography • high pressure liquid chromatography • mass spectral analysis • transcription factors • TATA binding protein-associated factors • chromatin assembly and disassembly • cyclin A