title: A dominant role for DNA secondary structure in forming hypersensitive structures in chromatin.
abstract: Previous work has suggested that potential information in DNA secondary structure might be used by cells to define DNAase 1- and S1-sensitive chromatin structures associated with promoter and terminator regions. To test this hypothesis, supercoiled pBR322 was cotransfected into L cells. For the majority of transfected clones supercoil-induced S1-sensitive sites in pure pBR322 DNA are also S1-sensitive in L-cell nuclei. These results suggest that the potential of certain DNA sequences to form specific secondary structures in chromatin can be a dominant characteristic. A recombinant chicken beta A-globin supercoiled plasmid was reconstituted in vitro with histones. The reconstituted chromatin also retained the ability to form S1-sensitive sites. Evidence suggests that DNA sequences capable of forming S1-sensitive sites in supercoiled plasmids may bind nucleosomes poorly after reconstitution with histones.
mesh_terms: D000818:Animals; D001483:Base Sequence; D002843:Chromatin / Q000378:metabolism*; D003001:Cloning, Molecular; D004247:DNA / Q000378:metabolism; D004278:DNA, Superhelical / Q000378:metabolism; D003851:Deoxyribonucleases / Q000494:pharmacology; D004720:Endonucleases / Q000494:pharmacology*; D005914:Globins / Q000235:genetics; D006657:Histones / Q000378:metabolism; D007739:L Cells; D051379:Mice; D009492:Neurospora crassa / Q000201:enzymology; D009690:Nucleic Acid Conformation; D009707:Nucleosomes / Q000378:metabolism; D010957:Plasmids; D015719:Single-Strand Specific DNA and RNA Endonucleases; D014162:Transfection
chemical_list: D002843:Chromatin; D004278:DNA, Superhelical; D006657:Histones; D009707:Nucleosomes; D005914:Globins; D004247:DNA; D003851:Deoxyribonucleases; D004720:Endonucleases; D015719:Single-Strand Specific DNA and RNA Endonucleases