Electrostatic surface potential of the HMG-1 box

The surface potential of the second HMG-1 box from rat HMG-1 is shown below. The majority of negatively-charged surfaces (shown in red) are located towards the bottom of the model, while there are several basic surfaces (shown in blue) on the opposing, concave surface. The conserved, positively-charged lysine and arginine residues flanked by prolines at positions 2 and 3 may be responsible for anchoring the DNA onto the concave surface of the protein. In addition, it has been proposed for human SRY that Ile 9 interacts with DNA through partial sidechain intercalation in the minor groove (King & Weiss, 1993).

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