Cloning and characterization of the rat neurotensin receptor gene promoter.

The 5'-terminal region of the rat neurotensin receptor (NTR) gene was isolated and characterized. Genomic Southern analysis revealed that the NTR gene occurs as a single copy in the rat haploid genome. The upstream putative promoter region did not contain canonical TATA or CAAT boxes but has a consensus sequence for the transcription factor Sp1. This promoter is embedded in a large G + C-rich domain with characteristics of an CpG island. Transfection experiments using neurotensin receptor-luciferase fusion genes demonstrated that the 5'-flanking sequence functions as a strong promoter in the NG-108-15 cell. Deletion analysis suggested the presence of a core promoter (-470 to -662) that drives the minimal expression of the NTR gene.