This short 71 residue domain is an HMG-box domain. HMG-box domains mediate re-modelling of chromatin-structure. Mammalian HMG-box proteins are of two types: those that are non-sequence-specific DNA-binding proteins with two HMG-box domains and a long highly acidic C-tail; and a diverse group of sequence-specific transcription factor-proteins with either a single HMG-box or up to six copies, and no acidic C-tail [1].

1: The HMG-box: a versatile protein domain occurring in a wide variety of DNA-binding proteins. Stros M, Launholt D, Grasser KD; Cell Mol Life Sci. 2007;64:2590-2606. PMID:17599239