TY - JOUR T1 - Transcriptional Modulation of Mouse μ-Opioid Receptor Distal Promoter Activity by Sox18 JF - Molecular Pharmacology JO - Mol Pharmacol SP - 1486 LP - 1496 DO - 10.1124/mol.59.6.1486 VL - 59 IS - 6 AU - Hee-Jeong Im AU - Dmitri Smirnov AU - Tomoaki Yuhi AU - Shalini Raghavan AU - Jane E. Olsson AU - George E. Muscat AU - Peter Koopman AU - Horace H. Loh Y1 - 2001/06/01 UR - http://molpharm.aspetjournals.org/content/59/6/1486.abstract N2 - Previously, we reported the presence of dual promoters, referred to as distal (DP) and proximal, with a negative regulatory element between them in the mouse μ-opioid receptor (mor) gene. Here we have identified a positive regulatory element influencingmor DP transcription, which contains multiple consensus binding motifs for Sox factors (sex-determining Sry-like high mobility group box-containing genes). In gel supershift assays, the Sox family member Sox18 bound directly to the multiple Sox consensus binding motifs of the mor DP enhancer. Overexpression of Sox18 cDNA increased luciferase activity regulated by the morDP, and did so in a Sox18 concentration-dependent manner. In contrast, overexpression of another Sox member, Sox5, triggered no suchtrans-activation of mor DP-driven luciferase activity or DNA-protein binding activity. These results suggest that Sox18 directly and specifically stimulatesmor gene expression, by trans-activating the mor DP enhancer. ER -