This submission contains the mass spectrometry files for the manuscript by Lambert, Picaud et al. that describes the characterization of interactome changes induced by JQ1 on the BET proteins. This submission contains 16 files associated with endogenous IP-MS analysis of BRD2, BRD3 and BRD4 (IgG was used as a negative control) from K562 cells treated with (+)-JQ1 or DMSO for 1 h; biological duplicate analyses were performed. Sample were analysed on a TripleTOF 5600 spectrometer; please note that the SWATH/DIA files were used for quantification (MSPLIT-DIA) while the DDA files were used for library construction. See the README file within "Materials and Methods" and the accompanying files for a complete description of MS data generated.