NCIt synonyms : HMG-1/-2; HMG-Box Protein; High Mobility Group B Protein;
NCIt definition : The HMG-Box Family proteins are relatively abundant vertebrate DNA-binding and bending
proteins that bind with structure specificity, rather than sequence specificity, and
plays an architectural role in the assembly of nucleoprotein complexes. They have
two homologous HMG-box DNA-binding domains connected by a short basic linker to an
acidic carboxy-terminal tail that differs in length. The length (and possibly sequence)
of the acidic tail may be the dominant factor in mediating the differences in properties
among themselves and finely tunes the DNA-binding properties of the tandem HMG boxes,
to fulfill different cellular roles. The tail is essential for structure-selective
DNA-binding of the HMG boxes to DNA minicircles in the presence of equimolar linear
DNA, and has little effect on the affinity for this already highly distorted DNA ligand,
in contrast to binding to linear and four-way junction DNA. (J Mol Biol 2000 304:135-49);