title: A study of an endogenous nucleolytic reaction and of the action micrococcal nuclease and DNAase I on a salt-soluble, compact form of chromatin.
abstract: The endogenous nucleolytic reaction occurring in rabbit thymus nuclear lysates has been studied at extended incubation times (up to 4 h). Production of nucleosomal polymers containing multiples of 205 base pairs of DNA was observed. The stability of the bands and the low release (1%) of acid-soluble nucleotides indicated there was only a small fraction of sensitive DNA between the subunits. The salt-soluble chromatin formed in the endogenous reaction at short incubation times (14--24 min) and purified over Sephadex G-200 has been treated with micrococcal nuclease and DNAase I. With micrococcal nuclease, nucleosomal polymers containing multiples of 201 base pairs of DNA were formed. Extensive digestion reaveled a core subunit containing 145 base pairs of DNA. With DNAase I only random degradation was observed and nucleosomal complexes were not produced.
mesh_terms: D000818:Animals; D002467:Cell Nucleus / Q000032:analysis; D002843:Chromatin; D004247:DNA; D003851:Deoxyribonucleases; D008836:Micrococcal Nuclease; D008970:Molecular Weight; D011817:Rabbits; D012492:Salts; D012995:Solubility; D013950:Thymus Gland
chemical_list: D002843:Chromatin; D012492:Salts; D004247:DNA; D003851:Deoxyribonucleases; D008836:Micrococcal Nuclease