1DCO

DCOH, A BIFUNCTIONAL PROTEIN-BINDING TRANSCRIPTIONAL COACTIVATOR

Summary for 1DCO

• Entry DOI: 10.2210/pdb1dco/pdb
• Descriptor: DCOH (2 entities in total)
• Functional Keywords: transcriptional stimulator, dimerization cofactor, dehydratase, 4a-carbinolamine dehydratase, transregulator of homeodomain proteins
• Biological source: Rattus norvegicus (Norway rat)
• Total number of polymer chains: 8
• Total formula weight: 96140.82

Authors

Cronk, J.D.,Endrizzi, J.A.,Alber, T. (deposition date: 1996-05-16, release date: 1996-12-07, Last modification date: 2024-02-07)

Primary citation

Cronk, J.D.,Endrizzi, J.A.,Alber, T.
High-resolution structures of the bifunctional enzyme and transcriptional coactivator DCoH and its complex with a product analogue.
Protein Sci., 5:1963-1972, 1996

PubMed Abstract: DCoH, the dimerization cofactor of hepatocyte nuclear factor 1 (HNF-1), functions as both a transcriptional coactivator and a pterin dehydratase. To probe the relationship between these two functions, the X-ray crystal structures of the free enzyme and its complex with the product analogue 7,8-dihydrobiopterin were refined at 2.3 A resolution. The ligand binds at four sites per tetrameric enzyme, with little apparent conformational change in the protein. Each active-site cleft is located in a subunit interface, adjacent to a prominent saddle motif that has structural similarities to the TATA binding protein. The pterin binds within an arch of aromatic residues that extends across one dimer interface. The bound ligand makes contacts to three conserved histidines, and this arrangement restricts proposals for the enzymatic mechanism of dehydration. The dihedral symmetry of DCoH suggests that binding to the dimerization domain of HNF-1 likely involves the superposition of two-fold rotation axes of the two proteins.

PubMed: 8897596

Experimental method

X-RAY DIFFRACTION (2.3 Å)