HMG1 and 2, and related ‘architectural’ DNA-binding proteins

The HMG-box proteins, one of the three classes of high mobility group (HMG) chromosomal proteins 1 1 The recent revisions of the nomenclature for the HMG proteins are detailed on p.152 of this issue of TiBS. The three families are now termed HMG-B, HMG-A and HMG-N. , bend DNA and bind preferentially to distorted DNA structures. The proteins appear to act primarily as architectural facilitators in the assembly of nucleoprotein complexes; for example, in effecting recombination and in the initiation of transcription. HMG-box proteins might be targeted to particular DNA sites in chromatin by either protein–protein interactions or recognition of specific DNA structures.