1dh3
From Proteopedia
|
CRYSTAL STRUCTURE OF A CREB BZIP-CRE COMPLEX REVEALS THE BASIS FOR CREB FAIMLY SELECTIVE DIMERIZATION AND DNA BINDING
Overview
The cAMP responsive element-binding protein (CREB) is central to second, messenger regulated transcription. To elucidate the structural mechanisms, of DNA binding and selective dimerization of CREB, we determined to 3.0 A, resolution, the structure of the CREB bZIP (residues 283-341) bound to a, 21-base pair deoxynucleotide that encompasses the canonical 8-base pair, somatostatin cAMP response element (SSCRE). The CREB dimer is stabilized, in part by ionic interactions from Arg(314) to Glu(319') and Glu(328) to, Lys(333') as well as a hydrogen bond network that links the carboxamide, side chains of Gln(322')-Asn(321)-Asn(321')-Gln(322). Critical to family, selective dimerization are intersubunit hydrogen bonds between basic, region residue Tyr(307) and leucine zipper residue Glu(312), which are, conserved in all CREB/CREM/ATF-1 family members. Strikingly, the structure, reveals a hexahydrated Mg(2+) ion bound in the cavity between the basic, region and SSCRE that makes a water-mediated DNA contact. DNA binding, studies demonstrate that Mg(2+) ions enhance CREB bZIP:SSCRE binding by, more than 25-fold and suggest a possible physiological role for this ion, in somatostatin cAMP response element and potentially other CRE-mediated, gene expression.
About this Structure
1DH3 is a Single protein structure of sequence from Mus musculus with MG as ligand. Full crystallographic information is available from OCA.
Reference
The structure of a CREB bZIP.somatostatin CRE complex reveals the basis for selective dimerization and divalent cation-enhanced DNA binding., Schumacher MA, Goodman RH, Brennan RG, J Biol Chem. 2000 Nov 10;275(45):35242-7. PMID:10952992
Page seeded by OCA on Tue Nov 20 13:16:59 2007
