Protein binding elements in the human β-polymerase promoter

• Published in: Nucleic acids research Vol. 18; no. 4; pp. 919 - 928
• Main Authors: ENGLANDER, E. W, WILSON, S. H
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 25.02.1990
• Subjects: Animals; Base Sequence; Binding, Competitive; Biological and medical sciences; Cell Line; Cell Nucleus - metabolism; DNA Polymerase I - genetics; Fundamental and applied biological sciences. Psychology; Genes; HeLa Cells - enzymology; Humans; Liver - metabolism; Male; Molecular and cellular biology; Molecular genetics; Molecular Sequence Data; Nuclear Proteins - metabolism; Oligonucleotide Probes; Promoter Regions, Genetic; promoters; Rats; Testis - metabolism; Transcription. Transcription factor. Splicing. Rna processing; Human; Cell line; Enzyme; Transcription promoter; Cyclic AMP; Trans acting regulatory factor; Homology; Molecular interaction; DNA polymerase β; Transcription factor; Palindromic sequence
• ISSN: 0305-1048; 1362-4962
• DOI: 10.1093/nar/18.4.919

The core promoter for human DNA polymerase beta contains discrete binding sites for mammalian nuclear proteins, as revealed by DNasel footprinting and gel mobility shift assays. Two sites correspond to sequences identical with the Sp1 factor binding element, and a third site includes an eight residue palindromic sequence, TGACGTCA, known as the CRE element of several cAMP responsive promoters; the 5 to 10 residues flanking this palindrome on each side have no apparent sequence homology with known elements in other promoters. Nuclear extract from a variety of tissues and cells were examined; these included rat liver and testes and cultured cells of human and hamster origin. The DNasel footprint is strong over and around the palindromic element for each of the extracts and is equivalent in size (approximately 22 residues); footprinting over the Sp1 binding sites is seen also. Two potential tissue-specific binding sites, present in liver but not in testes, were found corresponding to residues -13 to -10 and +33 to +48, respectively. Protein binding to the palindromic element was confirmed by an electrophoretic mobility shift assay with the core promoter as probe. Binding specificity of the 22 residue palindromic element, as revealed by oligonucleotide competition, is different from that of AP-1 binding element. Controlled proteolysis with trypsin was used to study structural properties of proteins forming the mobility shift bands. Following digestion with trypsin, most of the palindrome binding activity of each extract corresponded to a sharp, faster migrating band, potentially representing a DNA binding domain of the palindrome binding protein.