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1r0o
From Proteopedia
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Crystal Structure of the Heterodimeric Ecdysone Receptor DNA-binding Complex
Overview
Ecdysteroids initiate molting and metamorphosis in insects via a, heterodimeric receptor consisting of the ecdysone receptor (EcR) and, ultraspiracle (USP). The EcR-USP heterodimer preferentially mediates, transcription through highly degenerate pseudo-palindromic response, elements, resembling inverted repeats of 5'-AGGTCA-3' separated by 1 bp, (IR-1). The requirement for a heterodimeric arrangement of EcR-USP, subunits to bind to a symmetric DNA is unusual within the nuclear receptor, superfamily. We describe the 2.24 A structure of the EcR-USP DNA-binding, domain (DBD) heterodimer bound to an idealized IR-1 element. EcR and USP, use similar surfaces, and rely on the deformed minor groove of the DNA to, establish protein-protein contacts. As retinoid X receptor (RXR) is the, mammalian homolog of USP, we also solved the 2.60 A crystal structure of, the EcR-RXR DBD heterodimer on IR-1 and found the dimerization and, DNA-binding interfaces to be the same as in the EcR-USP complex. Sequence, alignments indicate that the EcR-RXR heterodimer is an important model for, understanding how the FXR-RXR heterodimer binds to IR-1 sites.
About this Structure
1R0O is a Protein complex structure of sequences from Drosophila melanogaster with ZN as ligand. Full crystallographic information is available from OCA.
Reference
Structure of the heterodimeric ecdysone receptor DNA-binding complex., Devarakonda S, Harp JM, Kim Y, Ozyhar A, Rastinejad F, EMBO J. 2003 Nov 3;22(21):5827-40. PMID:14592980
Page seeded by OCA on Wed Nov 21 01:10:10 2007
