title: DNase-sensitive sites in nucleosomes. Their relative suspectibilities depend on nuclease used.
abstract: We have used three endonucleases having different catalytic and physicochemical properties to digest HeLa nucleosomes (chromatin core particles) which had been labeled with 32P at their 5'-DNA termini. Each endonuclease nicks nucleosome DNA at the identical sites, supporting the idea that the conformation of the DNA within a nucleosome is the major factor influencing its nuclease susceptibility and indicating that nucleases can indeed yield important information as to nucleoprotein structure. On the other hand, the relaative susceptibility of a given site can differ for each nuclease, indicating that enzyme-substrate interactions unique for each enzyme influence the course of the reaction; this limits the structural information which can be obtained by using a single nuclease to study nucleoprotein structure.
mesh_terms: D001230:Aspergillus / Q000201:enzymology; D055598:Chemical Phenomena; D002621:Chemistry; D002843:Chromatin / Q000378:metabolism*; D004247:DNA / Q000378:metabolism; D003851:Deoxyribonucleases / Q000378:metabolism*; D004720:Endonucleases / Q000378:metabolism*; D006367:HeLa Cells; D009690:Nucleic Acid Conformation; D010447:Peptide Hydrolases / Q000378:metabolism; D013210:Staphylococcus / Q000201:enzymology; D013329:Structure-Activity Relationship
chemical_list: D002843:Chromatin; D004247:DNA; D003851:Deoxyribonucleases; D004720:Endonucleases; D010447:Peptide Hydrolases