Characterization of the Promoter Region of the Human Melanocortin-1 Receptor (MC1R) Gene

• Published in: Biochemical and biophysical research communications 1999-08, Vol.262 (2), p.452-460
• Main Authors: Moro, Osamu, Ideta, Ritsuro, Ifuku, Ohji
• Format: Article
• Language: English
• Subjects: Base Sequence; Cloning, Molecular; DNA Mutational Analysis; DNA-Binding Proteins - metabolism; Gene Expression Regulation; Genes, Reporter; Humans; Molecular Sequence Data; Promoter Regions, Genetic; Protein Binding; Receptors, Corticotropin - genetics; Receptors, Melanocortin; Reverse Transcriptase Polymerase Chain Reaction; Sequence Deletion; Transcription, Genetic; Tumor Cells, Cultured
• ISSN: 0006-291X; 1090-2104
• DOI: 10.1006/bbrc.1999.1228

We sequenced 3201 bp upstream from the ATG translation start codon of the human melanocortin-1 receptor (MC1R). A number of transcriptional initiation sites were detected over a region of ∼600 base pairs upstream of the receptor coding region. These consist of GC-rich regions, each including SP-1 consensus binding motifs. Neither a TATA nor a CAAT box was found in this region. The 5′-flanking region also contains the consensus regulatory elements for AP-1, AP-2, and several E-boxes. Gel shift assays targeting the three GC boxes confirmed binding of SP-1. A promoter assay revealed that the minimal region exhibiting promoter activity was located between nucleotides −517 and −282 in human melanoma SK-Mel-2 cells. Further deletion from −517 to −447, which removed an SP-1 site, completely abolished luciferase activity. In conclusion, the MC1R promoter shares the characteristics of many other GPCR promoters. These characteristics include GC-rich sequence, lack of a TATA box, and binding of SP-1.