A small subset of bromodomain containing proteins are the four bromodomain and extraterminal (BET) proteins (BRD2, BRD3, BRD4 and BRDT) which are characterised by the presence of two tandem bromodomains and an extraterminal domain. Their bromodomains are readers of acetylated lysine epigenetic lmarks on histones, and the proteins thus regulate transcription during cellular proliferation and differentiation processes. BET proteina also have recognised pathological functions and have become important therapeutic targets for major diseases such as cancer, neurological disorders, obesity and inflammation [1]. The most extensively studied member of this family is BRD4 which has established pro-carcinogenic activity, and against which small molecule inhibitors have been developed, primiarily for oncological indications.

1. Taniguchi Y. (2016) The Bromodomain and Extra-Terminal Domain (BET) Family: Functional Anatomy of BET Paralogous Proteins. Int J Mol Sci, 17 (11). [PMID:27827996]