TRANSCRIPTION INITIATION SITES AND PROMOTER STRUCTURE OF THE MOUSE TYPE-2 INOSITOL 1,4,5-TRISPHOSPHATE RECEPTOR GENE

Transcription initiation sites and the promoter sequence of the ubiqui tously expressed mouse type 2 inositol 1,4,5-trisphosphate receptor (I P(3)R2) gene were determined. In contrast to the nervous system-enrich ed IP3RI, the IP(3)R2 gene had multiple (seven major) transcription in itiation sites located 334 to 269 bp upstream from the first ATG codon . Transient luciferase assay revealed promoter activity of the IP(3)RZ sequence upstream from the transcription initiation sites. The IP(3)R 2 promoter was GC-rich and had no conventional TATA box, but had a GC box in the proximal promoter. Multiple transcription start sites were flanked by CpG islands, and various cis elements were located in the p romoter. These structural features are considered to be responsible fo r a profile of IP(3)R2 gene expression. (C) 1997 Elsevier Science B.V.