Cloning and characterization of the 5 '-flanking region for the mouse phospholipase C-delta 1 gene

To date, little is known about the molecular mechanisms controlling the reg ulation of phospholipase C-delta 1 (PLC-delta 1) gene expression. To unders tand the mechanisms responsible for the regulation of PLC-delta 1 gene expr ession, the 5'-flanking region of the mouse PLC-delta 1 gene was isolated f rom a mouse genomic DNA library. Primer extension analysis revealed that th ere is a single transcriptional start site located at 127 bases upstream fr om the translation start codon in the mouse PLC-delta 1 gene. DNA sequence analysis showed that the sequence around the transcriptional start site is very GC-rich and has no TATA or CAAT boxes. Transient expression of a lucif erase reporter gene under the control of serially deleted 5'-flanking seque nces revealed that the 160-base-pair region from -622 to -462 upstream of t he transcriptional start site includes a positive cis-acting element(s) for the efficient expression of the PLC-delta 1 gene. Gel retardation analysis suggests that multiple transcription factors bind to separate sites on the promoter region. Based on these results, our study suggests that the minim al essential region located at -622 to +70 is fully sufficient to confer hi gh-level transcriptional activity and contains high-affinity binding elemen ts for multiple transcription factors. (C) 2000 Academic Press.