PMID: 19043829 , Related PDB ids: 3DZU, 3DZY, 3E00

Authors:

Chandra V, Huang P, Hamuro Y, Raghuram S, Wang Y, Burris TP, Rastinejad F

Title:

Structure of the intact PPAR-gamma-RXR- nuclear receptor complex on DNA.

Journal:

Nature. 2008 Nov 20;456(7220):350-6.

Abstract:

Nuclear receptors are multi-domain transcription factors that bind to DNA elements from which they regulate gene expression. The peroxisome proliferator-activated receptors (PPARs) form heterodimers with the retinoid X receptor (RXR), and PPAR-gamma has been intensively studied as a drug target because of its link to insulin sensitization. Previous structural studies have focused on isolated DNA or ligand-binding segments, with no demonstration of how multiple domains cooperate to modulate receptor properties. Here we present structures of intact PPAR-gamma and RXR-alpha as a heterodimer bound to DNA, ligands and coactivator peptides. PPAR-gamma and RXR-alpha form a non-symmetric complex, allowing the ligand-binding domain (LBD) of PPAR-gamma to contact multiple domains in both proteins. Three interfaces link PPAR-gamma and RXR-alpha, including some that are DNA dependent. The PPAR-gamma LBD cooperates with both DNA-binding domains (DBDs) to enhance response-element binding. The A/B segments are highly dynamic, lacking folded substructures despite their gene-activation properties.