Bromodomain, SP100C_like subfamily. The SP100C protein is a splice variant of SP100, a major component of PML-SP100 nuclear bodies (NBs), which are poorly understood. It is covalently modified by SUMO-1 and may play a role in processes at the chromatin level. Bromodomains are 110 amino acid long domains, that are found in many chromatin associated proteins. Bromodomains can interact specifically with acetylated lysine.