Bromodomain, brd8_like subgroup. In mammals, brd8 (bromodomain containing 8) interacts with the thyroid hormone receptor in a ligand-dependent fashion and enhances thyroid hormone-dependent activation from thyroid response elements. Brd8 is thought to be a nuclear receptor coactivator. Bromodomains are 110 amino acid long domains, that are found in many chromatin associated proteins. Bromodomains can interact specifically with acetylated lysine.