| HMG (high-mobility group) box | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
 NMR structure of the HMG-box domain of theLEF1 protein (rainbow colored,N-terminus = blue,C-terminus = red) complexed with DNA (brown) based on thePDB:2LEF coordinates. | |||||||||||
| Identifiers | |||||||||||
| Symbol | PF00505 | ||||||||||
| Pfam | PF00505 | ||||||||||
| Pfam clan | CL0114 | ||||||||||
| ECOD | 190.1.1 | ||||||||||
| InterPro | IPR009071 | ||||||||||
| SCOP2 | 1hsm /SCOPe /SUPFAM | ||||||||||
| |||||||||||
Inmolecular biology, theHMG-box (high-mobilitygroup box) is aprotein domain which is involved inDNA binding.[1] The domain is composed of approximately 75 amino acid residues that collectively mediate the DNA-binding of chromatin-associatedhigh-mobility group proteins. HMG-boxes are present in many transcription factors and chromatin-remodeling complexes, where they can mediate non-sequence or sequence-specific DNA binding.[2]
The structure of the HMG-box domain contains threealpha helices separated by loops (see figure to the right).[3]
HMG-box containing proteins only bind non-B-type DNA conformations (kinked or unwound) with high affinity.[1] HMG-box domains are found in somehigh-mobility group proteins, which are involved in the regulation of DNA-dependent processes such astranscription,replication, andDNA repair, all of which require changing theconformation ofchromatin.[3]The single and the double box HMG proteins alter DNA architecture by inducing bends upon binding.[4][5]
