Crystal structure of the NR2E3 LBD is in an autorepressed conformation.

Abstract

<p><b>A</b>. Purification of the MBP<b>-</b>NR2E3 LBD-His₆ fusion protein. The molecular weight of full length MBP–NR2E3LBD-His₆ is 63.6 kDa. <b>B</b>. Overview of the NR2E3 dimer. Each monomer is colored purple, with helix 10 (H10) colored cyan and activation function domain 2 (AF2) colored yellow. <b>C</b>. Front and side views of the NR2E3 LBD monomer. The secondary structure assignment is labeled according to nuclear receptor testicular receptor 4 (TR4). <b>D</b>. The ligand binding pocket space within the bottom half of the NR2E3 LBD is occupied by large hydrophobic side chains (shown in red stick presentation). <b>E</b>. Hydrophobic interactions of the NR2E3 AF2 helix within the cofactor binding site. Positively charged surfaces are shown in blue, negatively charged surfaces in red, and the uncharged, hydrophobic groove in white. <b>F</b>. Overlay of the NR2E3 LBD structure with the SRC1 LXXLL motif (in green) from the RXR structure (1K74). <b>G</b>. Overlay of the NR2E3 LBD structure with the SMRT LXXIIXXXL corepressor motif (in magenta) from the antagonist-bound PPARα structure (1KKQ).</p