First Author | Di Polo A | Year | 1996 |
Journal | Invest Ophthalmol Vis Sci | Volume | 37 |
Issue | 4 | Pages | 551-60 |
PubMed ID | 8595955 | Mgi Jnum | J:32163 |
Mgi Id | MGI:79668 | Citation | Di Polo A, et al. (1996) Isolation and initial characterization of the 5' flanking region of the human and murine cyclic guanosine monophosphate-phosphodiesterase beta-subunit genes. Invest Ophthalmol Vis Sci 37(4):551-60 |
abstractText | PURPOSE: As an initial approach to study the mechanisms that direct photoreceptor-specific expression of the rod cyclic guanosine monophosphate-phosphodiesterase beta-subunit (beta-PDE) gene, the 5' flanking regions of the human and mouse genes were cloned and analyzed. METHODS: Genomic libraries were screened and clones containing the 5' upstream region of the beta-PDE gene were isolated and sequenced. Primer extension and ribonuclease protection assays were used to determine the transcription initiation sites. Sequences were compared using dot-matrix analysis and nucleotide alignment to determine potential regulatory elements that have been conserved through evolution. DNA-protein interactions were examined using DNAse I footprinting. RESULTS: The beta-PDE gene 5' sequence contains two distinct transcription start sites and lacks a TATA box. A stretch of approximately 30 nucleotides just upstream of the first transcribed nucleotide is strongly conserved in both species. This sequence contains a TATA-like element and a -CTAATC- motif previously described in other photoreceptor-specific genes. A highly-conserved AP-1 element, the recognition site for members of the jun and the fos oncoproteins family, is also present in this proximal region. DNAse I footprinting revealed an array of retinal proteins binding to these elements. CONCLUSIONS: The beta-PDE 5' region features match those of a highly tissue-specific gene in which factors restricted to the retina might play a role in gene activation. Elements conserved through evolution in the human and mouse sequences were found and analyzed as potential cis-acting elements. The availability of the human beta-PDE 5' upstream sequence will allow patients with retinal degeneration to be screened for possible mutations in these control sequences. |