Molecular cloning and characterization of the promoter of the human N-methylpurine-DNA glycosylase (MPG) gene.

The promoter region of the human N-methylpurine-DNA glycosylase (MPG) gene was cloned and characterized. The cloned segment contains two first exons that were earlier identified and named exons 1a and 1b. These were found to be separated by approximately 800 bp. The minimal promoter region was identified upstream to the distal exon 1a, by transient transfection, and no promoter activity was found in the region in between exons 1a and 1b, suggesting that transcription starts at a single site which is then processed to generate mRNAs of the isoforms. The promoter sequence is G and C rich and contains neither TATA box, nor apparent CAAT sequences, although a partially matched CAAT sequence was identified just downstream to the minimal promoter.