Kinase experiment:

Proteins are buffered in 10 mM HEPES, pH 7.5, 500 mM NaCl and assayed in a 96-well plate at a final concentration of 2 μM in 20 μL volume. Compounds (TPOP146) are added at a final concentration of 10 μM. SYPRO Orange (Molecular Probes) is added as a fluorescence probe at a dilution of 1:1000. Excitation and emission filters for the SYPRO Orange dye are set to 465 and 590 nm, respectively. The temperature is raised with a step of 3℃ per minute from 25 to 96℃, and fluorescence readings are taken at each interval[1].

TPOP146 is a selective CBP/P300 benzoxazepine bromodomain inhibitor with Kd values of 134 nM and 5.02 μM for CBP and BRD4.

Exposure to 1 μM TPOP146 results in a significant decrease of recovery half-life that is comparable to the construct that contained the bromodomain inactivating mutation N1168F, demonstrating that TPOP146 targets the CBP bromodomain in the nucleus and is capable of competing with acetyl-lysine mediated interactions of the CBP bromodomain in cellular environments[1].

[1]. Popp TA, et al. Development of Selective CBP/P300 Benzoxazepine Bromodomain Inhibitors. J Med Chem. 2016 Oct 13;59(19):8889-8912.