title: Mouse mu opioid receptor distal promoter transcriptional regulation by SOX proteins.
abstract: We have identified transcription factors that bind to specific sequences in 5'-distal promoter regulatory sequences of the mouse mu opioid receptor (mor) promoter using the yeast one-hybrid system. The sequence between -746 and -707 in mor distal promoter was used as the bait because it acts as a functional promoter element and binds several DNA-binding proteins. From an adult mouse brain cDNA library, five cDNA clones encoding three Sox gene family (Sry like high mobility group (HMG) box gene) transcriptional factors, mSOX18, mSOX21, and mSOX6, were isolated. Electrophoretic mobility shift assays confirmed the presence of a binding site for SOX proteins in the -731/-725 region. Additionally, we have also established that the flanking regions outside the core Sox-binding site play an essential role in high affinity binding. DNase I footprint analysis indicates that proteins from mouse brain interact with the Sox-binding site within the mor distal promoter. Finally, we demonstrated that overexpression of mSOX18 and/or mSOX21 was able to up-regulate mouse mor distal promoter activity in mor-expressing neuronal cells (NMB). These data indicate that SOX proteins might contribute to the transcriptional activity of the mor gene and suggest that mu opioid receptor could mediate some of the developmental processes in which SOX proteins are included.
authors.affiliation: Department of Pharmacology, University of Minnesota Medical School, Minneapolis 55455, USA. hwang025@umn.edu
authors.forename: Cheol Kyu
authors.initials: CK
authors.lastname: Hwang
authors.forename: Xiuli
authors.initials: X
authors.lastname: Wu
authors.forename: Guilin
authors.initials: G
authors.lastname: Wang
authors.forename: Chun Sung
authors.initials: CS
authors.lastname: Kim
authors.forename: Horace H
authors.initials: HH
authors.lastname: Loh
mesh_terms: D000818:Animals; D001483:Base Sequence; D018983:DNA Footprinting; D017931:DNA Primers; D004268:DNA-Binding Proteins / Q000502:physiology*; D024202:Electrophoretic Mobility Shift Assay; D005786:Gene Expression Regulation / Q000502:physiology*; D006609:High Mobility Group Proteins; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D017450:Receptors, Opioid, mu / Q000235:genetics*; D055749:SOXB2 Transcription Factors; D014157:Transcription Factors; D014158:Transcription, Genetic / Q000502:physiology*; D014407:Tumor Cells, Cultured
chemical_list: D017931:DNA Primers; D004268:DNA-Binding Proteins; D006609:High Mobility Group Proteins; D017450:Receptors, Opioid, mu; D055749:SOXB2 Transcription Factors; C484489:Sox21 protein, mouse; D014157:Transcription Factors