1r0n
From Proteopedia
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Crystal Structure of Heterodimeric Ecdsyone 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
1R0N is a Protein complex structure of sequences from Drosophila melanogaster and Homo sapiens 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
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