Crystallization of hepatocyte nuclear factor 1β in complex with DNA

Hepatocyte nuclear factor 1β (HNF1β) is a member of the POU transcription-factor family and binds the target DNA as a dimer with nanomolar affinity. The HNF1β–DNA complex has been prepared and crystallized by hanging-drop vapor diffusion in 6%(v/v) PEG 300, 5%(w/v) PEG 8000, 8%(v/v) glycerol and 0.1 M Tris pH 8.0. The crystals diffracted to 3.2 Å (93.9% completeness) using a synchrotron-radiation source under cryogenic (100 K) conditions and belong to space group R3, with unit-cell parameters a = b = 172.69, c = 72.43 Å. A molecular-replacement solution has been obtained and structure refinement is in progress. This structure will shed light on the molecular mechanism of promoter recognition by HNF1β and the molecular basis of the disease-causing mutations found in it.