TRANSCRIPTION OF THE MOUSE MU-OPIOID RECEPTOR GENE IS REGULATED BY 2 PROMOTERS

Two transcription initiation sites have been identified in the mouse m u-opioid receptor (MOR) gene at approximately - 793 and - 268 upstream of the translation start site. To test if the MOR gene contains two f unctional promoters, chimeric constructs of mouse MOR deletion fragmen ts, fused to a luciferase reporter gene, were transiently transfected into the neuroblastoma cell line SK-N-SH, a MOR-expressing cell line, and two MOR-non-expressing cell lines. Results from transient transfec tion assays confirmed the existence of two functional independent prom oters in the mouse MOR gene, and also revealed that the region from - 1337 to - 93 does not contain all the elements necessary to confer tis sue-specific expression of the MOR gene. (C) 1997 Elsevier Science B.V .