Our previous studies isolated and characterized eight splicing variants containing exon 11 as the first coding exon. The location of exon 11 about 10 kb upstream from exon 1 dual promoters implied another promoter to drive expression of the exon 11 variants. I now identify the second promoter in the 5′-flanking region of exon 11. One major transcriptional start point was determined. Sequence analysis indicated that the 5′-flanking region of the exon 11 contained a putative TATA box, several CAAT boxes and a number of cis-acting elements. Functional analysis suggested that exon 11 promoter activity was most evident in neuronal-like cells. A basal core region containing the TATA box, a negative region and a positive region were identified. Electrophoretic mobility shift assays with the nuclear extracts from NIE-115 cells revealed several protein complexes that likely contained TATA box-associated factors, NF-1-like and cMyc-Max-like proteins, respectively. It also showed that a TATA-binding protein specifically bound to the TATA box fragment. Mutation analysis suggested that the TATA box in the basal core region played a fundamental role in the exon 11 promoter, whereas the NF-1 site acted as a positive element.
All Science Journal Classification (ASJC) codes
- TATA box
- Transcription regulation