AN EFFICIENT METHOD FOR ISOLATING PUTATIVE PROMOTERS AND 5'-TRANSCRIBED SEQUENCES FROM LARGE GENOMIC CLONES

Efficient strategies to isolate promoters and flanking exons From larg e genomic clones would facilitate the assembly of transcription units, complement existing techniques to isolate expressed sequences, and pr ovide 5' regulatory elements. We have developed a rapid and simple met hod to isolate promoters from large mammalian genomic DNA clones by ex ploiting the abundance of binding sites for the ubiquitous transcripti on factor Sp1 in gene promoters. Using this method, putative promoter sequences with Spl-binding sites are enriched similar to 100-fold from fragmented PI clone DNA. Based on the abundance of Spl-binding motifs in promoters, we predict that a significant subset of vertebrate prom oters could be isolated by this method.