High mobility group proteins are proteins with an HMG-box domain that binds kinked or unwound DNA in a sequence non-specific way with high affinity. The HMG-box structure contains three alpha-helices separated by loops. HMG proteins contain two DNA-binding HMG-box domains that show structural and functional differences, as well as a long, acidic C-terminal domain rich in aspartic and glutamic acid residues. The HMG-box domain can be found in a wide variety of proteins serving many biological purposes, such as DNA repair, transcription, and recombination (PMID:19236006;19360789).